Christophe E. Depuydt

Bio: Christophe E. Depuydt is an academic researcher from Ghent University. The author has contributed to research in topics: Cervical cancer & Cervical intraepithelial neoplasia. The author has an hindex of 37, co-authored 88 publications receiving 3838 citations. Previous affiliations of Christophe E. Depuydt include Ghent University Hospital & University of Antwerp.

The fatty acid composition of phospholipids of spermatozoa from infertile patients

Abstract: The lipid composition of the sperm membrane has a significant effect upon the functional characteristics of spermatozoa. In the present study we investigated the fatty acid (FA) composition of subpopulations of spermatozoa separated on a discontinuous Percoll gradient (47:90%) and the FA composition of phospholipids (PL) of sperm heads and tails in both normal and abnormal semen samples. In normozoospermic samples, polyunsaturated fatty acids (PUFA) represented 34.0 +/- 1.3 (mean +/- SE, mole %) and 25.6 +/- 1.2% of total FA of PL of the 47 and 90% Percoll fractions respectively. Docosahexaenoic acid (22:6omega3, DHA) contributed to more than 60% of total PUFA. DHA was significantly lower in both the 47% (P < 0.05) and the 90% (P < 0.01) Percoll fractions of oligozoospermic samples and in the 90% Percoll layer of asthenozoospermic samples (P < 0.01), compared with normozoospermic samples. The omega6/omega3 ratio was significantly increased in both Percoll fractions of samples with oligozoospermia (47%, P < 0.001 and 90%, P < 0.001) or with asthenozoospermia (47%, P < 0.05 and 90%, P < 0.001) compared with normozoospermic samples. The oxidative potential index (OPI) of spermatozoa recovered from the 47% Percoll layer was significantly higher (P < 0.0001) than of those recovered from the 90% Percoll. Mean melting point (MMP), an index of membrane fluidity, was significantly lower in head than in tails (P < 0.01) of spermatozoa, and also in both the 47% (P < 0.01) and 90% (P < 0.001) Percoll fractions of normozoospermic samples in comparison with oligozoospermic samples. The MMP was significantly higher (P < 0.05) in samples of patients with idiopathic oligo/asthenozoospermia, varicocele, and male accessory gland infection (MAGI). These differences in FA composition of PL in subpopulations of human spermatozoa, and in their heads and tails may be related to sperm maturity and to differences in physiological function.

The effects of combined conventional treatment, oral antioxidants and essential fatty acids on sperm biology in subfertile men.

Abstract: We evaluated the effects of combined conventional treatment, oral antioxidants (N-acetyl-cysteine or vitamins A plus E) and essential fatty acids (FA) on sperm biology in an open prospective study including 27 infertile men. The evaluation included sperm characteristics, seminal reactive oxygen species (ROS), FA of sperm membrane phospholipids, sperm oxidized DNA (8-OH-dG), and induced acrosome reaction (AR). Treatment did not improve sperm motility and morphology, nor decrease the concentration of round cells and white blood cells in semen. Sperm concentration increased in oligozoospermic men (7.4+/-1.3 to 12.5+/-1.9 million/ml). Treatment significantly reduced ROS (mean+/-SEM) (775.3+/-372.2 to 150.3+/-105.2 x 10(3)counts/10 second) and 8-OH-dG (45.3+/-10.4 to 16. 8+/-3.3 fmol/microg DNA). Treatment increased the AR (55.1+/-2.2 to 71.6+/-2.2%), the proportion of polyunsaturated FA of the phospholipids, and sperm membrane fluidity. The overall pregnancy rate was 4.5% in 134 months. The per month pregnancy rate tended to be higher in partners of (ex)-smokers (7.15%, n=14,70 months) than in never-smokers (1.6%, n=13,64 months) (OR:4.57, 95% Cl:0.55-38.1).

Mechanisms and effects of male genital tract infection on sperm quality and fertilizing potential: the andrologist's viewpoint

Abstract: There are several mechanisms acting in synergism that can impair sperm characteristics of patients with accessory gland infection In some cases, conventional sperm variables are disturbed with oligo and/or asthenozoospermia In other patients, these sperm variables may appear normal, but the functional capacity of spermatozoa may be impaired In particular, changes in the composition of the sperm membrane may result in reduced acrosome reactivity and capacity to fuse with the oolemma, and oxidative damage of the sperm DNA may induce mutagenesis Changes in the biochemical make-up of seminal plasma can also reduce the in-vivo fertilizing capacity of spermatozoa, and infection-related disruption of the blood-testis barrier can induce the generation of anti-sperm antibodies and immunological infertility Many of these functional abnormalities will not become evident upon 'basic semen analysis', which explains why some authors are unable to link infection of the accessory sex glands to subfertility Also, functional and anatomical damage acquired as a result of infection is often permanent and not reversible by (antibiotic) treatment Clearly, there are many more aspects of male accessory gland infection that require investigation Available data should stimulate clinicians to place more emphasis on the prevention of infection-related infertility than on its treatment, as the latter is often unsuccessful

Are 20 human papillomavirus types causing cervical cancer

Abstract: In 2012, the International Agency for Research on Cancer concluded that there was consistent and sufficient epidemiological, experimental and mechanistic evidence of carcinogenicity to humans for 12 HPV types (HPV16, HPV18, HPV31, HPV33, HPV35, HPV39, HPV45, HPV51, HPV52, HPV56, HPV58 and HPV59) for cervical cancer. Therefore, these types were considered as 1A carcinogens. They all belong to the family of the α-Papillomaviridae, in particular to the species α5 (HPV51), α6 (HPV56), α7 (HPV18, HPV39, HPV45, HPV59) and α9 (HPV16, HPV31, HPV33, HPV35, HPV52, HPV58). Less evidence is available for a thirteenth type (HPV68, α7), which is classified as a 2A carcinogen (probably carcinogenic). Moreover, seven other phylogenetically related types (HPV26, HPV53, HPV66, HPV67, HPV68, HPV70 and HPV73) were identified as single HPV infections in certain rare cases of cervical cancer and were considered possibly carcinogenic (2B carcinogens). Recently, Halec et al [7] demonstrated that the molecular signature of HPV-induced carcinogenesis (presence of type-specific spliced E6*| mRNA; increased expression of p16; and decreased expression of cyclin D1, p53 and Rb) was similar in cervical cancers containing single infections with one of the eight afore-mentioned 2A or 2B carcinogens to those in cancers with single infections with group 1 carcinogens. Ninety six percent of cervical cancers are attributable to one of the 13 most common HPV types (groups 1 and 2A). Including the additional seven HPV types (group 2B) added 2.6%, to reach a total of 98.7% of all HPV-positive cervical cancers. From recently updated meta-analyses, it was shown that HPV68, HPV26, HPV66, HPV67, HPV73 and HPV82 were significantly more common in cancer cases than in women with normal cervical cytology, suggesting that for these HPV types, an upgrading of the carcinogen classification could be considered. However, there is no need to include them in HPV screening tests or vaccines, given their rarity in cervical cancers. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Worldwide prevalence and genotype distribution of cervical human papillomavirus DNA in women with normal cytology: a meta-analysis.

Abstract: Summary We set out to estimate the age and genotype-specific prevalence of cervical human papillomavirus (HPV) DNA in women with normal cervical cytology worldwide by meta-analysis of a systematic literature review. Reports on HPV prevalence published between January, 1995, and January, 2005, were retrieved. To be included, studies required information on cervical cytology, plus detailed descriptions of study populations, methods used to collect cervical samples, and assays used for HPV DNA detection and typing. Final analyses included 78 studies that could be separated into women with normal cytology, and of which subsets of 44 and 48 studies had data on age and type-specific HPV prevalence, respectively. Overall HPV prevalence in 157 879 women with normal cervical cytology was estimated to be 10·4% (95% CI 10·2–10·7). Corresponding estimates by region were Africa 22·1% (20·9–23·4), Central America and Mexico 20·4% (19·3–21·4), northern America 11·3% (10·6–12·1), Europe 8·1% (7·8–8·4), and Asia 8·0% (7·5–8·4). In all world regions, HPV prevalence was highest in women younger than 35 years of age, decreasing in women of older age. In Africa, the Americas, and Europe, a clear second peak of HPV prevalence was observed in women aged 45 years or older. On the basis of these estimates, around 291 million women worldwide are carriers of HPV DNA, of whom 32% are infected with HPV16 or HPV18, or both. The HPV types most commonly detected are similar to those most commonly described in pre-neoplastic and cancer cases, although the relative contribution of HPV16 and HPV18 is substantially lower in cytologically normal women.

Oxidative stress and male infertility—a clinical perspective

Abstract: Oxidative stress occurs when the production of potentially destructive reactive oxygen species (ROS) exceeds the bodies own natural antioxidant defenses, resulting in cellular damage. Oxidative stress is a common pathology seen in approximately half of all infertile men. ROS, defined as including oxygen ions, free radicals and peroxides are generated by sperm and seminal leukocytes within semen and produce infertility by two key mechanisms. First, they damage the sperm membrane, decreasing sperm motility and its ability to fuse with the oocyte. Second, ROS can alter the sperm DNA, resulting in the passage of defective paternal DNA on to the conceptus. This review will provide an overview of oxidative biochemistry related to sperm health and will identify which men are most at risk of oxidative infertility. Finally, the review will outline methods available for diagnosing oxidative stress and the various treatments available.

Burden of HIV among female sex workers in low-income and middle-income countries: a systematic review and meta-analysis.

Abstract: Summary Background Female sex workers are a population who are at heightened risk of HIV infection secondary to biological, behavioural, and structural risk factors. However, three decades into the HIV pandemic, understanding of the burden of HIV among these women remains limited. We aimed to assess the burden of HIV in this population compared with that of other women of reproductive age. Methods We searched PubMed, Embase, Global Health, SCOPUS, PsycINFO, Sociological Abstracts, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Web of Science, and POPLine for studies of female sex workers in low-income and middle-income countries published between Jan 1, 2007, and June 25, 2011. Studies of any design that measured the prevalence or incidence of HIV among female sex workers, even if sex workers were not the main focus of the study, were included. Meta-analyses were done with the Mantel-Haenszel method with a random-effects model characterising an odds ratio for the prevalence of HIV among female sex workers compared with that for all women of reproductive age. Findings Of 434 selected articles and surveillance reports, 102 were included in the analyses, representing 99 878 female sex workers in 50 countries. The overall HIV prevalence was 11·8% (95% CI 11·6–12·0) with a pooled odds ratio for HIV infection of 13·5 (95% CI 10·0–18·1) with wide intraregional ranges in the pooled HIV prevalence and odds ratios for HIV infection. In 26 countries with medium and high background HIV prevalence, 30·7% (95% CI 30·2–31·3; 8627 of 28 075) of sex workers were HIV-positive and the odds ratio for infection was 11·6 (95% CI 9·1–14·8). Interpretation Although data characterising HIV risk among female sex workers is scarce, the burden of disease is disproportionately high. These data suggest an urgent need to scale up access to quality HIV prevention programmes. Considerations of the legal and policy environments in which sex workers operate and actions to address the important role of stigma, discrimination, and violence targeting female sex workers is needed. Funding The World Bank, UN Population Fund.

Chlamydia, gonorrhoea, trichomoniasis and syphilis: global prevalence and incidence estimates, 2016.

Abstract: Objective To generate estimates of the global prevalence and incidence of urogenital infection with chlamydia, gonorrhoea, trichomoniasis and syphilis in women and men, aged 15–49 years, in 2016.