151 research outputs found

    Detrimental Effects of Non-Functional Spermatozoa on the Freezability of Functional Spermatozoa from Boar Ejaculate

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    In the present study, the impact of non-functional spermatozoa on the cryopreservation success of functional boar spermatozoa was evaluated. Fifteen sperm-rich ejaculate fractions collected from five fertile boars were frozen with different proportions of induced non-functional sperm (0 –native semen sample-, 25, 50 and 75% non-functional spermatozoa). After thawing, the recovery of motile and viable spermatozoa was assessed, and the functional of the spermatozoa was evaluated from plasma membrane fluidity and intracellular reactive oxygen species (ROS) generation upon exposure to capacitation conditions. In addition, the lipid peroxidation of the plasma membrane was assessed by the indirect measurement of malondialdehyde (MDA) generation. The normalized (with respect to a native semen sample) sperm motility (assessed by CASA) and viability (cytometrically assessed after staining with Hoechst 33342, propidium iodide and fluorescein-conjugated peanut agglutinin) decreased (p<0.01) as the proportion of functional spermatozoa in the semen samples before freezing decreased, irrespective of the semen donor. However, the magnitude of the effect differed (p<0.01) among boars. Moreover, semen samples with the largest non-functional sperm subpopulation before freezing showed the highest (p<0.01) levels of MDA after thawing. The thawed viable spermatozoa of semen samples with a high proportion of non-functional spermatozoa before freezing were also functionally different from those of samples with a low proportion of non-functional spermatozoa. These differences consisted of higher (p<0.01) levels of intracellular ROS generation (assessed with 5-(and-6) chloromethyl-20,70-dichlorodihydrofluorescein diacetate acetyl ester; CM-H2DCFDA) and increased (p<0.01) membrane fluidity (assessed with Merocyanine 540). These findings indicate that non-functional spermatozoa in the semen samples before freezing negatively influence the freezability of functional spermatozoa

    Patient adherence to and tolerability of self-administered interferon β-1a using an electronic autoinjection device: a multicentre, open-label, phase IV study

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    <p>Abstract</p> <p>Background</p> <p>Achieving good adherence to self-injected treatments for multiple sclerosis can be difficult. Injection devices may help to overcome some of the injection-related barriers to adherence that can be experienced by patients. We sought to assess short-term adherence to, and tolerability of, interferon (IFN) β-1a administered via electronic autoinjection device in patients with relapsing-remitting multiple sclerosis (RRMS).</p> <p>Methods</p> <p>BRIDGE (RebiSmart to self-inject Rebif serum-free formulation in a multidose cartridge) was a 12-week, multicentre, open-label, single-arm, observational, Phase IV study in which patients self-administered IFN β-1a (titrated to 44 μg), subcutaneously (sc), three times weekly, via electronic autoinjection device. Patients were assessed at baseline and 4-weekly intervals to Week 12 or early termination (ET) for: physical examinations; diary card completion (baseline, Weeks 4, 8 only); neurological examinations (baseline, Week 12/ET only); MS Treatment Concern Questionnaire (MSTCQ; Weeks 4, 8, 12 only); Convenience Questionnaire (Week 12 only); Hospital Anxiety and Depression Scale (HADS); and Paced Auditory Serial Addition Task (PASAT; baseline only). Adherence was defined as administration of ≥ 80% of scheduled injections, recorded by the autoinjection device.</p> <p>Results</p> <p>Overall, 88.2% (105/119; intent-to-treat population) of patients were adherent; 67.2% (80/119) administered all scheduled injections. Medical reasons accounted for 35.6% (31/87) of missed injections, forgetfulness for 20.6% (18/87). Adherence did not correlate with baseline Expanded Disability Status Scale (<it>P </it>= 0.821) or PASAT (<it>P </it>= 0.952) scores, or pre-study therapy (<it>P </it>= 0.303). No significant changes (baseline-Week 12) in mean HADS depression (<it>P </it>= 0.482) or anxiety (<it>P </it>= 0.156) scores were observed. 'Overall convenience' was the most important reported benefit of the autoinjection device. Device features associated with handling and ease of use were highly rated. Mean MSTCQ scores for 'flu-like' symptoms (<it>P </it>= 0.022) and global side effects (<it>P </it>= 0.002) significantly improved from Week 4-12. Mean MSTCQ scores for pain at injection site and injection pain increased from Week 4-12 (<it>P </it>< 0.001). Adverse events were mild/moderate. No new safety signals were identified.</p> <p>Conclusion</p> <p>Convenience and ease of use of the autoinjection device may improve adherence and, therefore, outcomes, in patients with RRMS receiving sc IFN β-1a.</p> <p>Trial registration</p> <p>EU Clinical Trials Register (EU-CTR; <url>http://www.clinicaltrialsregister.eu</url>): 2009-013333-24</p

    Examination of polymorphic glutathione S-transferase (GST) genes, tobacco smoking and prostate cancer risk among Men of African Descent: A case-control study

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    <p>Abstract</p> <p>Background</p> <p>Polymorphisms in <it>glutathione S-transferase </it>(GST) genes may influence response to oxidative stress and modify prostate cancer (PCA) susceptibility. These enzymes generally detoxify endogenous and exogenous agents, but also participate in the activation and inactivation of oxidative metabolites that may contribute to PCA development. Genetic variations within selected <it>GST </it>genes may influence PCA risk following exposure to carcinogen compounds found in cigarette smoke and decreased the ability to detoxify them. Thus, we evaluated the effects of polymorphic <it>GSTs </it>(<it>M1</it>, <it>T1</it>, and <it>P1</it>) alone and combined with cigarette smoking on PCA susceptibility.</p> <p>Methods</p> <p>In order to evaluate the effects of <it>GST </it>polymorphisms in relation to PCA risk, we used TaqMan allelic discrimination assays along with a multi-faceted statistical strategy involving conventional and advanced statistical methodologies (e.g., Multifactor Dimensionality Reduction and Interaction Graphs). Genetic profiles collected from 873 men of African-descent (208 cases and 665 controls) were utilized to systematically evaluate the single and joint modifying effects of <it>GSTM1 </it>and <it>GSTT1 </it>gene deletions, <it>GSTP1 </it>105 Val and cigarette smoking on PCA risk.</p> <p>Results</p> <p>We observed a moderately significant association between risk among men possessing at least one variant <it>GSTP1 </it>105 Val allele (OR = 1.56; 95%CI = 0.95-2.58; p = 0.049), which was confirmed by MDR permutation testing (p = 0.001). We did not observe any significant single gene effects among <it>GSTM1 </it>(OR = 1.08; 95%CI = 0.65-1.82; p = 0.718) and <it>GSTT1 </it>(OR = 1.15; 95%CI = 0.66-2.02; p = 0.622) on PCA risk among all subjects. Although the <it>GSTM1</it>-<it>GSTP1 </it>pairwise combination was selected as the best two factor LR and MDR models (p = 0.01), assessment of the hierarchical entropy graph suggested that the observed synergistic effect was primarily driven by the <it>GSTP1 </it>Val marker. Notably, the <it>GSTM1</it>-<it>GSTP1 </it>axis did not provide additional information gain when compared to either loci alone based on a hierarchical entropy algorithm and graph. Smoking status did not significantly modify the relationship between the <it>GST </it>SNPs and PCA.</p> <p>Conclusion</p> <p>A moderately significant association was observed between PCA risk and men possessing at least one variant <it>GSTP1 </it>105 Val allele (p = 0.049) among men of African descent. We also observed a 2.1-fold increase in PCA risk associated with men possessing the <it>GSTP1 </it>(Val/Val) and <it>GSTM1 </it>(*1/*1 + *1/*0) alleles. MDR analysis validated these findings; detecting <it>GSTP1 </it>105 Val (p = 0.001) as the best single factor for predicting PCA risk. Our findings emphasize the importance of utilizing a combination of traditional and advanced statistical tools to identify and validate single gene and multi-locus interactions in relation to cancer susceptibility.</p

    Choline Dehydrogenase Polymorphism rs12676 Is a Functional Variation and Is Associated with Changes in Human Sperm Cell Function

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    Approximately 15% of couples are affected by infertility and up to half of these cases arise from male factor infertility. Unidentified genetic aberrations such as chromosomal deletions, translocations and single nucleotide polymorphisms (SNPs) may be the underlying cause of many cases of idiopathic male infertility. Deletion of the choline dehydrogenase (Chdh) gene in mice results in decreased male fertility due to diminished sperm motility; sperm from Chdh−/− males have decreased ATP concentrations likely stemming from abnormal sperm mitochondrial morphology and function in these cells. Several SNPs have been identified in the human CHDH gene that may result in altered CHDH enzymatic activity. rs12676 (G233T), a non-synonymous SNP located in the CHDH coding region, is associated with increased susceptibility to dietary choline deficiency and risk of breast cancer. We now report evidence that this SNP is also associated with altered sperm motility patterns and dysmorphic mitochondrial structure in sperm. Sperm produced by men who are GT or TT for rs12676 have 40% and 73% lower ATP concentrations, respectively, in their sperm. rs12676 is associated with decreased CHDH protein in sperm and hepatocytes. A second SNP located in the coding region of IL17BR, rs1025689, is linked to altered sperm motility characteristics and changes in choline metabolite concentrations in sperm

    Assessing the feasibility of adaptation options: methodological advancements and directions for climate adaptation research and practice

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    The Paris Agreement put adaptation prominently on the global climate action agenda. Despite a surge in research and praxis-based knowledge on adaptation, a critical policy roadblock is synthesizing and assessing this burgeoning evidence. We develop an approach to assess the multidimensional feasibility of adaptation options in a robust and transparent manner, providing direction for global climate policy and identifying knowledge gaps to further future climate research. The approach, which was tested in the IPCC Special Report on 1.5 °C (SR1.5) to assess 23 adaptation options, is underpinned by a systematic review of recent literature, expert elicitation, and iterative peer review. It responds to the challenge of limited agreement on adaptation indicators, lack of fine-scale adaptation data, and challenges of assessing synergies and trade-offs with mitigation. The findings offer methodological insights into how future assessments such as the IPCC Assessment Report (AR) six and regional, national, and sectoral assessment exercises could assess adaptation feasibility and synthesize the growing body of knowledge on climate change adaptation

    Reactive oxygen species and male reproductive hormones

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    Reports of the increasing incidence of male infertility paired with decreasing semen quality have triggered studies on the effects of lifestyle and environmental factors on the male reproductive potential. There are numerous exogenous and endogenous factors that are able to induce excessive production of reactive oxygen species (ROS) beyond that of cellular antioxidant capacity, thus causing oxidative stress. In turn, oxidative stress negatively affects male reproductive functions and may induce infertility either directly or indirectly by affecting the hypothalamus-pituitary-gonadal (HPG) axis and/or disrupting its crosstalk with other hormonal axes. This review discusses the important exogenous and endogenous factors leading to the generation of ROS in different parts of the male reproductive tract. It also highlights the negative impact of oxidative stress on the regulation and cross-talk between the reproductive hormones. It further describes the mechanism of ROS-induced derangement of male reproductive hormonal profiles that could ultimately lead to male infertility. An understanding of the disruptive effects of ROS on male reproductive hormones would encourage further investigations directed towards the prevention of ROS-mediated hormonal imbalances, which in turn could help in the management of male infertility

    Chlorinated biphenyls effect on estrogen-related receptor expression, steroid secretion, mitochondria ultrastructure but not on mitochondrial membrane potential in Leydig cells

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