High FSH decreases the developmental potential of mouse oocytes and resulting fertilized embryos, but does not influence offspring physiology and behavior in vitro or in vivo

STUDY QUESTION

Do different concentrations of FSH in the assisted reproductive technology (ART) procedure in vitro or in vivo affect the developmental competence of oocytes, the embryos and the offspring conceived from these embryos?

SUMMARY ANSWER

Improper FSH treatment (200 IU/l in vitro, 10 IU/ml in vivo and 200 IU/ml in vivo) impairs the development competence of oocyte and embryo, but does not influence offspring physiology and behavior.

WHAT IS KNOWN ALREADY

Exogenous FSH has been widely used in the field of ART. However, the effects of different concentrations of FSH on the developmental competence of oocytes, embryos and the offspring conceived from these embryos, are still unknown.

STUDY DESIGN, SIZE, DURATION

In a prospective study, a total of 45 mice at 8–10 weeks of age were primed in vivo with different dosages of FSH (9 mice in the 10 IU/ml, 10 mice in the 50 IU/ml, 10 mice in the 100 IU/ml and 16 mice in the 200 IU/ml groups). Fresh MII oocytes were retrieved from ovaries: this was designated as in vivo group. Thirty six mice at 8–10 weeks of age were sacrificed by cervical dislocation to obtain ovaries without FSH treatment (9 mice in the 0 IU/l, 9 mice in the 50 IU/l, 8 mice in the 100 IU/l and 10 mice in the 200 IU/l groups), and then the immature oocytes were collected from these ovaries and cultured in vitro matured medium supplemented with 0, 50, 100 and 200 IU/l FSH: this was designated as in vitro group.

MATERIALS, SETTING, METHODS

Spindle assembly of matured MII oocytes was stained via an immunofluorescence method and the oocytes ratio of normal spindle was analyzed. The developmental competence of the resulting fertilized embryos in the pre- and post-implantation stages was examined in in vitro and in vivo groups. Furthermore, physiological index, including reproductive potential and body weight, of the offspring was investigated by mating experiments and behavior index, including learning, memory, probing and intelligence, was tested by Morris water maze in in vitro and in vivo groups.

MAIN RESULTS AND THE ROLE OF CHANCE

In the in vitro groups, the oocyte maturation competence, normal spindle assembly, blastocyst formation and implantation, as well as viable pup production were all impaired in the group treated with 200 IU/l FSH (P < 0.05). No differences were observed among the other three groups (P > 0.05). In the in vivo groups, 10 IU/ml FSH but not 200 IU/ml treatment influenced blastocyst formation and viable pup production (P < 0.05), although the high proportion of spindle assembly abnormality was only observed in the 200 IU/ml FSH treatment group (P < 0.05). Furthermore, there were no significant differences in terms of physiological index (reproductive potential and body weight) and behavior index (learning, memory, probing and intelligence) in offspring from in vitro and in vivo groups (P > 0.05).

LIMITATIONS, REASONS FOR CAUTION

The mouse model was used in this study. The results of the mouse follicle growth and oocyte development in responding to different concentrations of FSH are not 100% transferable to human, because of the physiological differences between mouse and human.

WIDER IMPLICATIONS OF THE FINDINGS

The findings indicated that FSH application in the field of ART is safe to the resulted offspring, but it should be more carefully used for each women in ART cycles because the inappropriate FSH concentration would decrease the oocyte developmental competence.

STUDY FUNDING/COMPETING INTEREST(S)

This work was partially supported by the Ministry of Science and Technology of China Grants (973 program; 2011CB944504), the Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China (30825038), the National Natural Science Funds for Young Scholar (31000661) and by the Joint Research Fund for Overseas, Hong Kong and Marco Scholars (31128013/C120205). None of the authors has any conflicts of interest.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/5/1309?rss=1

Embryo culture media and IVF/ICSI success rates: a systematic review

BACKGROUND

The media that are used to culture human preimplantation embryos are considered to be an important factor for the success rates of IVF/ICSI. Here, we present a systematic review of randomized controlled trials (RCTs) on the effect of culture media on IVF/ICSI success rates.

METHODS

RCTs published between January 1985 and July 2012 were eligible for inclusion. The primary outcome was live birth. Secondary outcomes were health of babies born, ongoing pregnancies, clinical pregnancies, miscarriages, multiple pregnancies, implantation rate, cryopreservation rate, embryo quality and fertilization rate. For those media that were evaluated in more than one comparison, an unconventional meta-analysis was performed by pooling the data of the media they were compared to.

RESULTS

Twenty-two RCTs were included that evaluated 31 different comparisons. Conventional meta-analysis was not possible for any of the outcomes as nearly all trials compared different culture media. Only four trials reported on live birth, and one of them reported a significant difference. Nine trials reported on ongoing and/or clinical pregnancy rates, of which four showed a significant difference. Pooling the data did not reveal a superior culture medium.

CONCLUSIONS

It is yet unknown what culture medium leads to the best success rates in IVF/ICSI. Given the potential importance of culture media for treatment outcome, rigorously designed RCTs are needed for currently available, as well as newly introduced culture media.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/210?rss=1

The expression and functionality of stromal caveolin 1 in human adenomyosis

STUDY QUESTION

What is the expression pattern and functionality of caveolin 1 (CAV1) in the endometrium of patients with adenomyosis?

SUMMARY ANSWER

The stromal CAV1 expression is down-regulated that leads to the release of a variety of molecules that either enhance the metastatic capacity of endometrial cells or contribute to adenomyosis-associated dysmenorrhea.

WHAT IS KNOWN ALREADY

Adenomyosis is characterized by invasion of endometrium into the uterine myometrium. CAV1 has been linked to tumor progression and clinical outcome in a variety of human malignancies; however, its role in adenomyosis development and adenomyosis-associated dysmenorrhea is still poorly recognized.

STUDY DESIGN, SIZE, DURATION

We retrospectively analyzed the expression levels of CAV1 and RANTES protein using immunohistochemistry in 65 patients who were pathologically diagnosed with adenomyosis and 12 control women without related pathology, who were subjected to surgery between 2009 and 2010. Endometrial tissues from six additional normal females without related pathology were collected from 2011 to 2012; these tissues were subjected to subsequent primary cell culture experiments.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The expression of CAV1 and RANTES was examined by immunohistochemistry in ectopic endometrium and paired eutopic endometrium of 65 adenomyosis patients and 12 control patients. Primary endometrial stromal cells (ESCs) and endometrial epithelial cells (EECs) were isolated from 6 additional control females without related pathology. The expression of CAV1 in ESCs was either (i) inhibited by siRNA transfection and methyl-β-cyclodextrin (MβCD) treatment or (ii) increased by pcDNA3.1/CAV1 transfection. The impact of each treatment on the proliferation, migration and invasion of both ESCs and EECs was evaluated by methylthiazolydiphenyl-tetrazolium assay, colony formation assay, Transwell migration and invasion assay. Furthermore, ESC treatment with MβCD and siCAV1 was assessed for the effect on the expression of a panel of inflammatory cytokines. The levels of two pain mediators, nitric oxide (NO) and prostaglandin E2 (PGE2), were assessed in CAV-1-depleted and control ESCs, whereas immunoblotting was performed to characterize signaling pathways downstream to loss of stromal CAV1 in endometrium. The correlation between dysmenorrhea severity and stromal CAV1 and RANTES expression was further examined using ‘Pearson's’ correlation analysis.

MAIN RESULTS

Stromal CAV1 expression in ectopic endometrium of adenomyosis patients was significantly lower than that of paired eutopic endometrium or normal controls as analyzed by immunohistochemistry (P < 0.001). Although no significant difference was observed in the proliferation of CAV1-depleted ESCs when compared with control group, EECs cultured with conditioned media from CAV1-depleted ESCs demonstrated a significantly elevated proliferation rate when compared with those treated with control ESC-conditioned media. Moreover, both CAV1-depleted ESCs and EECs cultured with conditioned media from CAV1-depleted ESCs showed enhanced migration and invasion capacity when compared with control group (P < 0.05). In contrast, incubation with conditioned media of ESCs with enforced CAV1 expression led to decreased proliferation capacity of EECs. Furthermore, the expression of RANTES in ESCs treated with MβCD and siCAV1 was significantly increased. Stromal RANTES expression in the ectopic endometrium of adenomyosis patients was significantly higher than that of paired eutopic endometrium or normal controls as analyzed by immunohistochemistry (P = 0.0026). Stromal CAV1 expression in eutopic endometrium was significantly lower in women with more severe dysmenorrhea (P < 0.05) and was negatively correlated with dysmenorrhea severity in adenomyosis patients (r2 = 0.1549; P = 0.012, ‘Pearson's’ 2 test), whereas stromal RANTES expression in eutopic endometrium was significantly higher in women with more severe dysmenorrhea (P < 0.05) and was positively correlated with dysmenorrhea severity in adenomyosis patients (r2 = 0.1646; P = 0.0094, ‘Pearson's’ 2 test). Silencing of CAV1 in ESCs led to increased release of NO and PGE2 when compared with control and was associated with enhanced activity of ERK-FAK signaling pathway.

LIMITATIONS, REASONS FOR CAUTION

This study assessed the functional role of stromal CAV1 and RANTES in a small number of human adenomyosis samples by immunohistochemistry and in primary human ESCs by functional studies. In future investigations, a larger sample size should be adopted and the functional role of stromal CAV1 should be further characterized in animal models.

WIDER IMPLICATIONS OF THE FINDINGS

Loss of stromal CAV1 expression may play a critical role in the pathogenesis of adenomyosis and is correlated with adenomyosis-related dysmenorrhea.

STUDY FUNDING

National Basic Research Program of China and Ph.D. Programs Foundation of Ministry of Education of China.

COMPETING INTEREST

None.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/5/1324?rss=1

BMI in relation to sperm count: an updated systematic review and collaborative meta-analysis

BACKGROUND

The global obesity epidemic has paralleled a decrease in semen quality. Yet, the association between obesity and sperm parameters remains controversial. The purpose of this report was to update the evidence on the association between BMI and sperm count through a systematic review with meta-analysis.

METHODS

A systematic review of available literature (with no language restriction) was performed to investigate the impact of BMI on sperm count. Relevant studies published until June 2012 were identified from a Pubmed and EMBASE search. We also included unpublished data (n = 717 men) obtained from the Infertility Center of Bondy, France. Abstracts of relevant articles were examined and studies that could be included in this review were retrieved. Authors of relevant studies for the meta-analysis were contacted by email and asked to provide standardized data.

RESULTS

A total of 21 studies were included in the meta-analysis, resulting in a sample of 13 077 men from the general population and attending fertility clinics. Data were stratified according to the total sperm count as normozoospermia, oligozoospermia and azoospermia. Standardized weighted mean differences in sperm concentration did not differ significantly across BMI categories. There was a J-shaped relationship between BMI categories and risk of oligozoospermia or azoospermia. Compared with men of normal weight, the odds ratio (95% confidence interval) for oligozoospermia or azoospermia was 1.15 (0.93–1.43) for underweight, 1.11 (1.01–1.21) for overweight, 1.28 (1.06–1.55) for obese and 2.04 (1.59–2.62) for morbidly obese men.

CONCLUSIONS

Overweight and obesity were associated with an increased prevalence of azoospermia or oligozoospermia. The main limitation of this report is that studied populations varied, with men recruited from both the general population and infertile couples. Whether weight normalization could improve sperm parameters should be evaluated further.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/221?rss=1

The longer-term health outcomes for children born as a result of IVF treatment: Part I-General health outcomes

BACKGROUND

Several million children have been born from in vitro fertilization (IVF) treatment, but limited data exist regarding their health and development beyond the first year of life. It has been alleged that IVF may lead to long-term adverse consequences, in addition to the documented worse perinatal outcome and increased risk of congenital abnormalities in children born resulting from IVF treatment.

METHODS

A search strategy restricted to studies relating to the medical condition of children of at least 1 year of age born as a result of IVF treatment was performed to include case series, data linkage and prospective studies published 1 January 2000–1 April 2012.

RESULTS

Limited long-term follow-up data suggest that there is potentially an increase in the incidence of raised blood pressure, elevated fasting glucose, increase in total body fat composition, advancement of bone age and potentially subclinical thyroid disorder in the IVF offspring. Whether these potential associations are related to the IVF treatment per se, the adverse obstetric outcomes associated with IVF treatment or are related to the genetic origin of the children is yet to be determined.

CONCLUSIONS

This review provides evidence to suggest that the short-term health outcome for children born from IVF treatment is positive. However, it is expected that the cardiovascular and metabolic risk factors found in childhood and tracking into adulthood could be worse in later life, and may be responsible for chronic cardiometabolic disease. These observations need to be addressed by further studies.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/232?rss=1

The longer-term health outcomes for children born as a result of IVF treatment. Part II-Mental health and development outcomes

BACKGROUND

Limited data exist with regard to longer-term mental health and psychological functioning of children born from IVF treatment. With the known adverse perinatal outcome for children born from IVF treatment, it would be expected that there is a negative impact upon their mental development.

METHODS

A search strategy restricted to studies relating to the medical condition of children of at least 1 year of age, born from IVF treatment was performed to include case series, data linkage and prospective studies published from 1 January 2000 to 1 April 2012.

RESULTS

Limited long-term follow-up data suggest that there is an increase in the incidence of cerebral palsy and neurodevelopmental delay related to the confounders of prematurity and low birthweight. Previous reports of associations with autism and attention-deficit disorder are believed to be related to maternal and obstetric factors. There exists a potential increase in the prevalence of early adulthood clinical depression and binge drinking in the offspring of IVF, with the reassuring data of no changes with respect to cognitive development, school performance, social functioning and behaviour. Whether these potential associations are related to the IVF treatment, the adverse obstetric outcomes associated with IVF treatment, the genetic or subsequent environmental influences on the children is yet to be determined.

CONCLUSIONS

In general, the longer-term mental and emotional health outcome for children born from IVF treatment is reassuring, and is very similar to that of naturally conceived children; however, further studies are required to explore any association with depression, and its causality in more detail.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/244?rss=1

Levothyroxine treatment and pregnancy outcome in women with subclinical hypothyroidism undergoing assisted reproduction technologies: systematic review and meta-analysis of RCTs

BACKGROUND

Previous meta-analyses of observational data indicate that pregnant women with subclinical hypothyroidism have an increased risk of adverse pregnancy outcome. Potential benefits of levothyroxine (LT4) supplementation remain unclear, and no systematic review or meta-analysis of trial findings is available in a setting of assisted reproduction technologies (ART).

METHODS

Relevant trials published until August 2012 were identified by searching MEDLINE, EMBASE, Web of Knowledge, the Cochrane Controlled Trials Register databases and bibliographies of retrieved publications without language restrictions.

RESULTS

From 630 articles retrieved, we included three trials with data on 220 patients. One of these three trials stated ‘live delivery’ as outcome. LT4 treatment resulted in a significantly higher delivery rate, with a pooled relative risk (RR) of 2.76 (95% confidence limits 1.20–6.44; P = 0.018; I2 = 70%), a pooled absolute risk difference (ARD) of 36.3% (3.5–69.0%: P = 0.030) and a summary number needed to treat (NNT) of 3 (1–28) in favour of LT4 supplementation. LT4 treatment significantly lowered miscarriage rate with a pooled RR of 0.45 (0.24–0.82; P = 0.010; I2 = 26%), a pooled ARD of –31.3% (–48.2 to –14.5%: P < 0.001) and a summary NNT of 3 (2–7) in favour of LT4 supplementation. LT4 treatment had no effect on clinical pregnancy (RR 1.75; 0.90–3.38; P = 0.098; I2 = 82%). In an ART setting, no data are available on the effects of LT4 supplementation on premature delivery, arterial hypertension, placental abruption or pre-eclampsia.

CONCLUSIONS

Our meta-analyses provide evidence that LT4 supplementation should be recommended to improve clinical pregnancy outcome in women with subclinical hypothyroidism and/or thyroid autoimmunity undergoing ART. Further research is needed to determine pregnancy outcome after close monitoring of thyroid function to maintain thyroid-stimulating hormone and free T4 levels within the trimester-specific reference ranges for pregnancy.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/251?rss=1

Granulocyte-colony stimulating factor for hematopoietic stem cell donation from healthy female donors during pregnancy and lactation: what do we know?

BACKGROUND

Hematopoietic growth factors (HGFs) are mostly used as supportive measures to reduce infectious complications associated with neutropenia. Over the past decade, the use of HGFs became a common method for mobilizing human CD34+ stem cells, either for autologous or allogeneic transplantation. However, since their introduction the long-term safety of the procedure has become a major focus of discussion and research. Most information refers to healthy normal donors and data concerning pregnant and lactating women are scarce. The clinical question, which is the core of this review, is whether stem cell donation, preceded by administration of granulocyte-colony stimulating factor (G-CSF) for mobilization, is a safe procedure for pregnant donors.

METHODS

Literature searches were performed in Pubmed for English language articles published before the end of May 2012, focusing on G-CSF administration during pregnancy, lactation and hematopoietic stem cell donation. Searches included animal and human studies.

RESULTS

Data from animals (n = 15 studies) and women (n = 46 studies) indicate that G-CSF crosses the placenta, stimulates fetal granulopoiesis, improves neonatal survival mostly for very immature infants, promotes trophoblast growth and placental metabolism and has an anti-abortive role. Granulocyte macrophage-CSF is a key cytokine in the maternal immune tolerance towards the implanted embryo and exerts protective long-term programming effects to preimplantation embryos. The available data suggest that probably CSFs should not be administered during the time of most active organogenesis (first trimester), except perhaps for the first week during which implantation takes place. Provided CSF is administered during the second and third trimesters, it appears to be safe, and pregnant women receiving the CSF treatment can become hematopoietic stem cell donors. There are also risks related to the anesthesia, which is required for the bone marrow aspiration. During lactation, there should be a period of at least 3 days to allow for clearance of CSF from milk before resuming breast feeding. With regard to teratogenicity or leukaemogenity, in non-pregnant or non-lactating women reports show that CSF administration is associated with a risk for leukemia; however, this risk is not higher compared with the control population.

CONCLUSIONS

The information available to date indicates that administration of CSF in general, and G-CSF in particular, is safe and healthy pregnant women can serve as donors of either bone marrow or peripheral blood stem cells. However, the clinical experience is rather limited and therefore until more data become available, G-CSF should not be used during pregnancy and lactation when other therapeutic options, instead of stem cell transplantation, are available.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/259?rss=1

Circulating markers of oxidative stress and polycystic ovary syndrome (PCOS): a systematic review and meta-analysis

BACKGROUND

Oxidative stress might be associated with polycystic ovary syndrome (PCOS), but relatively small studies published to date do not permit reaching a definitive conclusion. We aimed at conducting a systematic review and meta-analysis of studies evaluating circulating markers of oxidative stress in patients with PCOS.

METHODS

We conducted a systematic review of studies reporting circulating markers of oxidative stress in women with PCOS and controls published up to June 2012, using Entrez PubMed and EMBASE online facilities. Meta-analysis calculated standardized mean differences (SMDs) and 95% confidence intervals (95CI).

RESULTS

From 1633 potential studies identified electronically, 68 studies, including 4933 PCOS patients and 3671 controls, were selected. For each of nine circulating markers of oxidative stress, an individual meta-analysis was conducted. Compared with control women, patients with PCOS presented higher circulating concentrations of homocysteine (23% increase, SMD 0.6, 95CI, 0.4–0.8), malondialdehyde (47% increase, SMD 1.9, 95CI 1.2–2.6) and asymmetric dimethylarginine (36% increase, SMD 1.1, 95CI 0.6–1.6), and increased superoxide dismutase activity (34% increase, SMD 1.0, 95CI 0.5–1.4) and decreased glutathione levels (50% decrease, SMD –3.7, 95CI –6.2 to –1.2) and paraoxonase-1 activity (32% decrease, SMD –0.9, 95CI –1.3 to –0.4). Similar results were found when restricting the analyses to studies in which patients and controls were matched for age and body mass index.

CONCLUSIONS

Circulating markers of oxidative stress are abnormal in women with PCOS independent of weight excess. This finding suggests that oxidative stress may participate in the pathophysiology of this common disorder.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/268?rss=1

Genetic variants in pre-eclampsia: a meta-analysis

BACKGROUND

Pre-eclampsia has a clear familial component, suggesting that the condition may be partly attributable to genetic susceptibility. The search for susceptibility genes has led to a drastic increase in the number of published studies associating genetic factors with pre-eclampsia. However, attempts to replicate these findings have yielded inconsistent results. This meta-analysis assessed the pooled effect of each genetic variant that is reproducibly associated with pre-eclampsia.

METHODS

Studies that assessed the association between genes and pre-eclampsia were searched in PubMed, Embase and Web of Science. We selected all genetic variants that were significantly associated with pre-eclampsia in an initial study and were subsequently independently reproduced in at least one additional study. All studies that assessed these reproduced variants were then included. The association between genetic variants and pre-eclampsia was calculated at the allele level, and the main measure of effect was a pooled odds ratio in a random-effects model.

RESULTS

The literature search yielded 2965 articles, of which 542 investigated genetic associations in pre-eclampsia. We identified 22 replicated genetic variants, of which 7 remained significantly associated with pre-eclampsia following meta-analysis. These variants were in or near the following genes: ACE, CTLA4, F2, FV, LPL and SERPINE1.

CONCLUSIONS

This meta-analysis identified seven genetic variants associated with pre-eclampsia. Importantly, many of these variants are also risk factors for developing cardiovascular disease, revealing that pre-eclampsia and cardiovascular disease have shared genetic risk factors. The contribution of the identified genetic variants in the pathogenesis of pre-eclampsia should be the focus of future studies.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/289?rss=1

Reproductive options for prospective parents in families with Huntington’s disease: clinical, psychological and ethical reflections

BACKGROUND

Huntington's disease (HD) is an autosomal dominant neurodegenerative late onset disorder. This review of reproductive options aims to increase reproductive confidence and to prevent suffering in relation to family planning around HD and possibly other late onset neurodegenerative disorders.

METHODS

Selected relevant literature and own views and experiences as clinical geneticists, psychologists and ethicists have been used.

RESULTS

Possible options, with emphasis on prenatal diagnosis (PD) and preimplantation genetic diagnosis (PGD) to prevent the transmission of HD to the next generation, are described and discussed. They are formally presented in a decision tree, taking into account the presence or absence of a fully penetrant allele (FPA), a reduced penetrant allele (RPA) or an intermediate allele (IA). A table compares invasive and non-invasive PD and PGD. From a psychological perspective, the complex process of counselling and decision-making regarding reproductive options is discussed. Special attention is paid to the decision to avoid the transmission of the mutation and to the confrontation and coping of a mutation-free child growing up with a parent developing disease symptoms. From an ethical point of view, reflections on both PD and PGD are brought forward taking into account the difference between FPA, RPA and IA, direct testing or exclusion testing and taking into account the welfare of the child in the context of medically assisted reproduction.

CONCLUSION

Recommendations and suggestions for good clinical practice in the reproductive care for HD families are formulated.

Source:
http://humupd.oxfordjournals.org/cgi/content/short/19/3/304?rss=1

The clinical significance of calcium-signalling pathways mediating human sperm hyperactivation

STUDY QUESTION

What is the prevalence of defects in the Ca2+-signalling pathways mediating hyperactivation (calcium influx and store mobilization) among donors and sub-fertile patients and are they functionally significant, i.e. related to fertilization success at IVF?

SUMMARY ANSWER

This study identifies, for the first time, the prevalence of Ca2+ store defects in sperm from research donors, IVF and ICSI patients. It highlights the biological role and importance of Ca2+ signalling (Ca2+ store mobilization) for fertilization at IVF.

WHAT IS KNOWN ALREADY

Sperm motility and hyperactivation (HA) are important for fertility, mice with sperm incapable of HA are sterile. Recently, there has been significant progress in our knowledge of the factors controlling these events, in particular the generation and regulation of calcium signals. Both pH-regulated membrane Ca2+ channels (CatSper) and Ca2+ stores (potentially activating store-operated Ca2+ channels) have been implicated in controlling HA.

STUDY DESIGN, SIZE, AND DURATION

This was a prospective study examining a panel of 68 donors and 181 sub-fertile patients attending the Assisted Conception Unit, Ninewells Hospital Dundee for IVF and ICSI. Twenty-five of the donors gave a second sample (~4 weeks later) to confirm consistency/reliability of the recorded responses. Ca2+ signalling was manipulated using three agonists, NH4Cl (activates CatSper via pH), progesterone (direct activation of CatSper channels, potentially enhancing mobilization of stored Ca2+ by CICR) and 4-aminopyridine (4-AP) (effect on pH equivalent to NH4Cl and mobilizes stored Ca2+). The broad-spectrum phosphodiesterase inhibitor 3-isobutyl-1-methyxanthine (IBMX), a potent activator of HA was also used for comparison. For patient samples, an aliquot surplus to requirements for IVF/ICSI treatment was examined, allowing direct comparison of Ca2+ signalling and motility data with functional competence of the sperm.

MATERIALS, SETTING, METHODS

The donors and sub-fertile patients were screened for HA (using CASA) and changes in intracellular Ca2+ were assessed by loading with Fura-2 and measuring fluorescence using a plate reader (FluoStar).

MAIN RESULTS AND THE ROLE OF CHANCE

The relative efficacy of the stimuli in inducing HA was 4-AP >> IBMX > progesterone. NH4Cl increased [Ca2+]i similarly to 4-AP and progesterone but did not induce a significant increase in HA. Failure of samples to generate HA (no significant increase in response to stimulation with 4-AP) was seen in just 2% of research donors but occurred in 10% of IVF patients (P = 0.025). All donor samples generated a significant [Ca2+]i increase when stimulated with 4-AP but 3.3% of IVF and 28.6% of ICSI patients failed to respond. Amplitudes of HA and [Ca2+]i responses to 4-AP were correlated with fertilization rate at IVF (P= 0.029; P = 0.031, respectively). Progesterone reliably induced [Ca2+]i responses (97% of donors, 100% of IVF patients) but was significantly less effective than 4-AP in inducing HA. Twenty seven per cent of ICSI patients failed to generate a [Ca2+]i response to progesterone (P= 0.035). Progesterone-induced [Ca2+]i responses were correlated with fertilization rate at IVF (P= 0.037) but induction of HA was not. In donor samples examined on more than one occasion consistent responses for 4-AP-induced [Ca2+]i (R2 = 0.97) and HA (R2 = 0.579) were obtained. In summary, the data indicate that defects in Ca2+ signalling leading to poor HA do occur and that ability to undergo Ca2+ -induced HA affects IVF fertilizing capacity. The data also confirm that release of stored Ca2+ is the crucial component of Ca2+ signals leading to HA and that Ca2+ store defects may therefore underlie HA failure.

LIMITATIONS, REASONS FOR CAUTION

This is an in vitro study of sperm function. While the repeatability of the [Ca2+]i and HA responses in samples from the same donor were confirmed, data for patients were from 1 assessment and thus the robustness of the failed responses in patients’ needs to be established. The focus of this study was on using 4AP, which mobilizes stored Ca2+ and is a potent inducer of HA. The n values for other agonists, especially calcium assessments, are smaller.

WIDER IMPLICATIONS OF THE FINDINGS

Previous studies have shown a significant relationship between basal levels of HA, calcium responses to progesterone and IVF fertilization rates. Here, we have systematically investigated the ability/failure of human sperm to generate Ca2+ signals and HA in response to targeted pharmacological challenge and, related defects in these responses to IVF success. [Ca2+]i signalling is fundamental for sperm motility and data from this study will lead to assessment of the nature of these defects using techniques such as single-cell imaging and patch clamping.

STUDY FUNDING/COMPETING INTEREST(S)

Resources from a Wellcome Trust Project Grant (#086470, Publicover and Barratt PI) primarily funded the study. The authors have no competing interests.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/4/866?rss=1

Identification of sperm head proteins involved in zona pellucida binding

STUDY QUESTION

Which human sperm proteins interact with zona pellucida (ZP) glycoproteins, ZPA/2, ZPB/4 and ZPC/3?

SUMMARY ANSWER

Co-precipitation experiments with recombinant human ZP (rhZP) coated beads demonstrated interactions with various proteins, including glutathione S-transferase M3 (GSTM) with ZPB/4 and voltage-dependent anion channel 2 (VDAC2) with ZPA/2 and ZPC/3.

WHAT IS KNOWN ALREADY

Regarding sperm–ZP binding, several target spot/proteins have been detected in several species, but not all have been characterized. The limit of these studies was that a mixture of the different ZP glycoproteins was used and did not allow the identification of the specific ZP glycoprotein (ZPA/2, ZPC/3 or ZPB/4) involved in the interaction with the sperm proteins.

STUDY DESIGN, SIZE, DURATION

To identify the human sperm proteins interacting with the oocyte ZP, we combined two approaches: immunoblot of human spermatozoa targeted by antisperm antibodies (ASAs) from infertile men and far western blot of human sperm proteins overlayd by each of the rhZP proteins.

MATERIALS, SETTING, METHODS

We used rhZP expressed in Chinese hamster ovary (CHO) cells and ASA eluted from infertile patients undergoing IVF failure. Sperm proteins separated by two-dimensional (2D) electrophoresis recognized by both sperm-eluted ASAs from infertile patients and rhZP were identified by mass spectrometry (MALDI-MS/MS). Some of these proteins were further validated by co-precipitation experiments with rhZP and functional zona binding tests.

MAIN RESULTS AND THE ROLE OF CHANCE

We identified proteins that are glycolytic enzymes such as pyruvate kinase 3, enolase 1, glyceraldehyde-3-phosphate dehydrogenase, aldolase A, triosephosphate isomerase, detoxification enzymes such as GSTM or phospholipid hydroperoxide glutathione peroxidase, ion channels such as VDAC2 and structural proteins such as outer dense fibre 2. Several of the proteins were localized on the sperm head. However, these proteins have also been described to exert other functions in the flagellum. Co-precipitation experiments with rhZP-coated beads confirmed the direct interaction of GSTM with ZP4 and of VDAC2 with ZP2 and ZP3.

LIMITATIONS, REASONS FOR CAUTION

We used recombinant ZP in place of native ZP. Thus, the post-translational modifications of the proteins, such as glycosylations, can be different and can influence their function. However, CHO cell-expressed rhZP are functional, e.g. can bind human spermatozoa and induce the acrosome reaction. Moreover, the identification of relevant proteins was limited by the need for sufficient amounts of proteins on the preparative 2D-gel to be subsequently analysed in MALDI-TOF MS/MS.

WIDER IMPLICATIONS OF THE FINDINGS

Our results bring new insights on the ability of sperm proteins to exert several functions depending on their sub-cellular localization, either the head or flagellum. Their multiple roles suggest that these sperm proteins are multifaceted or moonlighting proteins.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the grant ReproRio (CNRS, INRA, INSERM and CEA) and the Société d'Andrologie de Langue Française.

Trial registration number

Not applicable.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/4/852?rss=1

The Legacy of Jennifer Schlecht and the Tragedy of her Loss – Philanthropy Women

The global reproductive rights community is reeling with the tragic and untimely death of Jennifer Schlecht on November 6, 2019. A devoted and dedicated friend to women and girls everywhere, Schlecht had spent her entire career fostering family planning efforts for women across the globe. In recent years, she directed special attention to the need to provide family planning services for women drawn into humanitarian crises.

In April of 2018, Jennifer Schlecht took a new position as Senior Advisor on Emergency Preparedness and Response at Family Planning 2020. For Family Planning 2020, housed under the umbrella of United Nations Foundations activities, Schlecht collaborated with CARE on these issues as well as the Inter-Agency Working Group on Reproductive Health in Crisis.

Asked when she joined FP2020, What sparked your interest in family planning? Schlecht responded:

Familyplanning is key to empowerment. No matter where you work, I find thisto be true.

Schlecht came to this newly structured position from her work on Sexual and Reproductive Health at the Womens Refugee Commission, where she had worked for seven years. In these positions Schlecht, who was a highly respected leader in the fields of international relief and development, traveled extensively to advocate for reproductive services to women in various countries, among them Kenya and Tanzania. In a statement by Womens Relief Commission Executive Director Sarah Costa honored Schlecht, She brought joy and light to all who knew her and was an unyielding champion for the rights of displaced women everywhere. Most of all, she was a phenomenal mother who loved her daughter with all she had. Our hearts are broken today and our prayers are with Jenn and her family.

Just a year ago at the International Family Planning Conference held in Kigali from November 12-15 Jennifer Schlecht was interviewed on video for Reproductive Health Matters:

Women who are displaced have the same reproductive health needs as other women if not more. They have a right to access to family planningI love the fact that we have had so many amazing panels.But the most thrilling part is to actually see how it is raised. So, to hear the topic raised in plenaries, to hear it being discussed in groups that have not typically engaged in this space. I think there is an increased acceptance or understanding that crises are not something that happen there or to other people. This is a human condition, a circumstance, our operating environment. And it excites me to see that it is being discussed in that way. It opens so many more opportunities for all of us.

All week colleagues, fellow workers in the international reproductive health community, neighbors and friends have been paying tribute to this remarkable and vibrant leader who has worked relentlessly for the rights of women and girls.

Executive Director of FP2020, Beth Schlachter issued a statement: She was a leader in the field of family planning and humanitarian response, and chose to work from New York so she could have more time with her darling daughter.We are utterly devastated.

Women Deliver, Executive Director Katja Iversen @Katja_Iversen tweeted: We were horrified by the tragic news and devastated by the loss of Jennifer Schlecht, a WD friend and fellow advocate for girls, women, #genderequality and #SRHR. She improved 1000s of lives, and her memory will live on. Our thoughts are with you and her family.

A tweet from DOCTORS OF THE WORLD@_MdMUSA The Doctors of the World/MdM Intl Network mourns the loss of Jennifer Schlecht. We will remember her for her tireless work improving womens lives throughout the world. Our condolences to her family and many colleagues in the FP community @unfoundation @FP2020Global @IAWG_RH

November 9th community member Esther Spindler @Esther_Spindler tweeted: Purple balloons on empty benches tonight in Marcus Garvey park remembering the life of Jennifer Schlecht & her daughter, who died at the hands of brutal domestic violence. Feeling saddened, shocked, enraged & that weve failed our neighbor and colleague. She posted a photo.

The tragedy of Jennifer Schlechts death a woman who fought for the number one issue in womens lives, reproduction was that she was taken out by the number two issue that confronts many women of all socio-economic strata: domestic violence. On the very day she planned to go to court for a restraining order against her husband, he murdered her with a large blade. He then killed their six year old daughter. Finally, he hanged himself.

It is well documented that the most vulnerable time for women in intimate partner violence situations is when they attempt to leave or have left the abusive partner. Murder rates rise substantially. At the time the woman is particularly vulnerable, and, as well, often the children. Wendy Mahoney, executive director for the Mississippi Coalition Against Domestic Violence explained in a 2017 article Domestic violence is all about power and control, and when a woman leaves, a man has lost his power and control. She claimed the danger rate to be 500 times greater. Such unnerved loss of control was the case with Schlechts spouse, Yonathan Tedla. He had days earlier threatened, he was not going to lose in a divorce battle.

Better education and awareness about the various stages of intimate partner violence are clearly critical for all segments of the society to understand. Domestic violence is a public health issue. Stepped up education, programs and social pressure for change are necessary. The Center for Disease Control outlines some of this in a report from two years ago.

A British criminology expert, Dr Jane Monckton Smith, has found that there are eight stages leading up to such killings. She studied 372 intimate partner killings in the United Kingdom to define this pattern of escalation in the violence. Through domestic violence groups, police forces and health providers learning these steps can help to save lives in the future.

With our hearts heavy here at Philanthropy Women, we believe Jennifer Schlechts death needs to serve as moment for growth. Our community needs to come together and find more solutions to domestic violence. We need to more find ways to make it safe for women to share when they are being abused or threatened, and give them more options to remove themselves from the situation.

The United Nations Foundation, founded over two decades ago by Ted Turner, has a long track record in advancing programs for women and girls. Reproductive health has been central to their mission from its inception. In 2013 they started The Girl Declaration with 25 non-governmental organizations. Maybe a new goal initiated through the foundation can be to eradicate the 38% of womens homicides worldwide that the World Health Organization has identified come from intimate partner violence.

Rest in Peace, Jennifer and Abaynesh. Rest in Power, Jennifer and Abaynesh.

Related

Ariel Dougherty is a teacher, filmmaker, producer and mentor for women directed media/culture of all stripes. SWEET BANANAS (director, 1973) and !WOMEN ART REVOLUTION (Producer, 2010) are among the hundreds of films she has worked on. She writes at the intersections of women-identified media, especially film production, women's human rights, and funding for film. Currently, she is working on a book entitled Feminist Filmmaking Within Communities.View all posts by Ariel Dougherty

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The Legacy of Jennifer Schlecht and the Tragedy of her Loss - Philanthropy Women

Seminal and molecular evidence that sauna exposure affects human spermatogenesis

STUDY QUESTION

What are the effects of continuous sauna exposure on seminal parameters, sperm chromatin, sperm apoptosis and expression of genes involved in heat stress and hypoxia?

SUMMARY ANSWER

Scrotal hyperthermia by exposure to sauna can induce a significant alteration of spermatogenesis.

WHAT IS KNOWN ALREADY

Several authors have evidenced that high temperature has dramatic effects on spermatogenesis.

STUDY DESIGN, SIZE AND DURATION

A longitudinal time-course study. Data from 10 subjects exposed to Finnish sauna were collected before sauna (T0), after3 months of sauna sessions (T1) and after 3 (T2) and 6 months (T3) from the end of sauna exposure.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

Ten normozoospermic volunteers underwent two sauna sessions per week for 3 months, at 80–90°C, each lasting 15 min. Sex hormones, sperm parameters, sperm chromatin structure, sperm apoptosis and expression of genes involved in heat stress and hypoxia were evaluated at the start, at the end of sauna exposure and after 3 and 6 months from sauna discontinuation. Student's t-test for paired data was used for statistical analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

At the end of sauna exposure, we found a strong impairment of sperm count and motility (P < 0.001), while no significant change in sex hormones was present. Decreases in the percentage of sperm with normal histone-protamine substitution (78.7 ± 4.5 versus 69.0 ± 4.1), chromatin condensation (70.7 ± 4.7 versus 63.6 ± 3.3) and mitochondrial function (76.8 ± 4.9 versus 54.0 ± 6.1) were also evident at T1, and strong parallel up-regulation of genes involved in response to heat stress and hypoxia was found. All these effects were completely reversed at T3.

LIMITATIONS AND REASONS FOR CAUTION

Absence of subjects with abnormal sperm parameters was the major limitation of this study.

WIDER IMPLICATIONS OF THE FINDINGS

Our data demonstrated for the first time that in normozoospermic subjects, sauna exposure induces a significant but reversible impairment of spermatogenesis, including alteration of sperm parameters, mitochondrial function and sperm DNA packaging. The large use of Finnish sauna in Nordic countries and its growing use in other parts of the world make it important to consider the impact of this lifestyle choice on men's fertility.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was sought for this study and the authors have no conflict of interest to declare.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/4/877?rss=1

Spermatogonial stem cell preservation and transplantation: from research to clinic

STUDY QUESTION

What issues remain to be solved before fertility preservation and transplantation can be offered to prepubertal boys?

SUMMARY ANSWER

The main issues that need further investigation are malignant cell decontamination, improvement of in vivo fertility restoration and in vitro maturation.

WHAT IS KNOWN ALREADY

Prepubertal boys who need gonadotoxic treatment might render sterile for the rest of their life. As these boys do not yet produce sperm cells, they cannot benefit from sperm banking. Spermatogonial stem cell (SSC) banking followed by autologous transplantation has been proposed as a fertility preservation strategy. But before this technique can be applied in the clinic, some important issues have to be resolved.

STUDY DESIGN, SIZE DURATION

Original articles as well as review articles published in English were included in a search of the literature.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Relevant studies were selected by an extensive Medline search. Search terms were fertility preservation, cryopreservation, prepubertal, SSC, testis tissue, transplantation, grafting and in vitro spermatogenesis. The final number of studies selected for this review was 102.

MAIN RESULTS AND THE ROLE OF CHANCE

Cryopreservation protocols for testicular tissue have been developed and are already being used in the clinic. Since the efficiency and safety of SSC transplantation have been reported in mice, transplantation methods are now being adapted to the human testes. Very recently, a few publications reported on in vitro spermatogenesis in mice, but this technique is still far from being applied in a clinical setting.

LIMITATIONS, REASONS FOR CAUTION

Using tissue from cancer patients holds a potential risk for contamination of the collected testicular tissue. Therefore, it is of immense importance to separate malignant cells from the cell suspension before transplantation. Because biopsies obtained from young boys are small and contain only few SSCs, propagation of these cells in vitro will be necessary.

WIDER IMPLICATIONS OF THE FINDINGS

The ultimate use of the banked tissue will depend on the patient's disease. If the patient was suffering from a non-malignant disease, tissue grafting might be offered. In cancer patients, decontaminated cell suspensions will be injected in the testis. For patients with Klinefelter syndrome, the only option would be in vitro spermatogenesis. However, at present, restoring fertility in cancer and Klinefelter patients is not yet possible.

STUDY FUNDING/COMPETING INTEREST(S)

Research Foundation, Flanders (G.0385.08 to H.T.), the Institute for the Agency for Innovation, Belgium (IWT/SB/111245 to E.G.), the Flemish League against Cancer (to E.G.), Kom op tegen kanker (G.0547.11 to H.T.) and the Fund Willy Gepts (to HT). E.G. is a Postdoctoral Fellow of the FWO, Research Foundation, Flanders. There are no conflicts of interest.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/4/897?rss=1

Perinatal germ cell development and differentiation in the male marmoset (Callithrix jacchus): similarities with the human and differences from the rat

STUDY QUESTION

Is perinatal germ cell (GC) differentiation in the marmoset similar to that in the human?

SUMMARY ANSWER

In a process comparable with the human, marmoset GC differentiate rapidly after birth, losing OCT4 expression after 5–7 weeks of age during mini-puberty.

WHAT IS KNOWN ALREADY

Most of our understanding about perinatal GC development derives from rodents, in which all gonocytes (undifferentiated GC) co-ordinately lose expression of the pluripotency factor OCT4 and stop proliferating in late gestation. Then after birth these differentiated GC migrate to the basal lamina and resume proliferation prior to the onset of spermatogenesis. In humans, fetal GC differentiation occurs gradually and asynchronously and OCT4+ GC persist into perinatal life. Failure to switch off OCT4 in GC perinatally can lead to development of carcinoma in situ (CIS), the precursor of testicular germ cell cancer (TGCC), for which there is no animal model. Marmosets show similarities to the human, but systematic evaluation of perinatal GC development in this species is lacking. Similarity, especially for loss of OCT4 expression, would support use of the marmoset as a model for the human and for studying CIS origins.

STUDY DESIGN, SIZE AND DURATION

Testis tissues were obtained from marmosets (n = 4–10 per age) at 12–17 weeks' gestation and post-natal weeks 0.5, 2.5, 5–7, 14 and 22 weeks, humans at 15–18 weeks' gestation (n = 5) and 4–5 weeks of age (n = 4) and rats at embryonic day 21.5 (e21.5) (n = 3) and post-natal days 4, 6 and 8 (n = 4 each).

PARTICIPANTS/MATERIALS, SETTING AND METHODS

Testis sections from fetal and post-natal marmosets, humans and rats were collected and immunostained for OCT4 and VASA to identify undifferentiated and differentiated GC, respectively, and for Ki67, to identify proliferating GC. Stereological quantification of GC numbers, differentiation (% OCT4+ GC) and proliferation were performed in perinatal marmosets and humans. Quantification of GC position within seminiferous cords was performed in marmosets, humans and rats.

MAIN RESULTS AND ROLE OF CHANCE

The total GC number increased 17-fold from birth to 22 post-natal weeks in marmosets; OCT4+ and VASA+ GC proliferated equally in late gestation and early post-natal life. The percentage of OCT4+ GC fell from 54% in late fetal life to <0.5% at 2.5 weeks of age and none were detected after 5–7 weeks in marmosets. In humans, the percentage of OCT4+ GC also declined markedly during the equivalent period. In marmosets, GC had begun migrating to the base of seminiferous cords at ~22 weeks of age, after the loss of GC OCT4 expression.

LIMITATIONS, REASONS FOR CAUTION

There is considerable individual variation between marmosets. Although GC development in marmosets and humans was similar, there are differences with respect to proliferation during fetal life. The number of human samples was limited.

WIDER IMPLICATIONS OF THE FINDINGS

The similarities in testicular GC differentiation between marmosets and humans during the perinatal period, and their differences from rodents, suggest that the marmoset may be a useful model for studying the origins of CIS, with relevance for the study of TGCC.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by Grant G33253 from the Medical Research Council, UK. No external funding was sought and there are no competing interests.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/4/886?rss=1

Relationship between maternal asthma, its severity and control and abortion

STUDY QUESTION

Are women with asthma, and more specifically those with severe or uncontrolled asthma, at higher risk of spontaneous and induced abortions?

SUMMARY ANSWER

Pregnant women with asthma, notably when uncontrolled, are at higher risk of spontaneous abortion.

WHAT IS KNOWN ALREADY

Only one study has examined the association between asthma and spontaneous and induced abortions and revealed a modest increase in the risk of spontaneous abortions, particularly in women with more severe asthma and those with previous exacerbations, and a marginal decrease in the risk of induced abortions.

STUDY DESIGN, SIZE, DURATION

A cohort of pregnancies from asthmatic (n = 15 107) and non-asthmatic (n = 34 331) women was reconstructed by linking three administrative databases from Quebec (Canada), between 1992 and 2002. The cohort included 7870 spontaneous abortions, 14 596 induced abortions and 26 972 live births.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Pregnant women with and without asthma were analyzed. Asthma was defined by at least one asthma diagnosis and one dispensed prescription for an asthma medication in the 2 years prior to or during pregnancy. Asthma severity and control were assessed using validated indexes in the year before the 20th week of pregnancy or the termination of the pregnancy. Logistic polytomous regression models were used to estimate the relationship between asthma and asthma severity and control on the risk of abortion, while adjusting for potential confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

The prevalence of spontaneous and induced abortions was 15.9 and 29.5%, respectively. Maternal asthma was associated with an increased risk of a spontaneous abortion [odds ratio (OR) = 1.41; 95% confidence interval (CI): 1.33–1.49] and a decreased risk of induced abortions (OR = 0.92; 0.88–0.97). No association was observed between asthma severity and abortion, while uncontrolled asthma increased the risk of a spontaneous abortion by 26% (95% CI: 14–41%) and the risk of induced abortions by 11% (95% CI: 1–21%).

LIMITATIONS, REASONS FOR CAUTION

It is possible that the study results were confounded by imbalances between groups in variables that are not recorded in the databases, but that are known to be associated with spontaneous abortions, such as alcohol consumption, obesity or maternal smoking. However, we performed sensitivity analyses which revealed that these factors are unlikely to explain the observed increased risk for a spontaneous abortion. It is also possible that women with asthma are more likely to have abortions recorded in the databases, because subjects with a chronic disease tend to visit a physician more often than those without asthma. Therefore, our odds estimates for these outcomes may be overestimated when asthmatic women were compared with non-asthmatic women. A further limitation of the study is that it would have been more appropriate to measure the severity and control of asthma only during the pregnancy.

WIDER IMPLICATIONS OF THE FINDINGS

Our cohort is less representative of women in the upper socio-economic level. This is not a threat to internal validity, but it could limit the external validity if the impact of asthma on the risk of abortion differed according to the socio-economic status of the mother. Despite the absence of supporting data, this possibility cannot be completely excluded.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Canadian Institutes of Health Research and Genentech. L.B. received research grants from Astra-Zeneca, Pfizer, sanofi-aventis, Novartis and Merck for research projects and co-chairs the Astra-Zeneca Endowment Pharmaceutical Chair in Respiratory Health. F.Z.K and A.F. have no competing interests to declare.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/4/908?rss=1