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L D Klentzeris

Publications and source records attributed to L D Klentzeris.

14 recordsLinked to original sources
PubMed2001

The effects of meiosis activating sterol on in-vitro maturation and fertilization of human oocytes from stimulated and unstimulated ovaries.

The object of this study was to assess functional maturation in vitro by obtaining data on the fertilization and embryonic competence of human oocytes with or without exposure to meiosis activating sterol (MAS) during maturation in vitro. Immature oocytes were either collected from unstimulated patients with polycystic ovaries (PCO) during gynaecological surgery, or were donated by patients undergoing a cycle of intracytoplasmic sperm injection (ICSI) treatment including ovarian stimulation with gonadotrophins. PCO oocytes had variable cumulus cover, which was retained during culture while those from ICSI patients were cultured without cumulus. The study included 119 oocytes from PCO patients and 72 from ICSI patients. The oocytes were allowed to mature in vitro for up to 46 h in the presence or absence of MAS. Mature oocytes were inseminated by ICSI with fertile donor spermatozoa and embryo development was monitored in vitro. MAS (30 microg/ml) significantly increased the survival of oocytes from PCO patients (P < 0.01) but did not significantly affect the proportion completing maturation in vitro. For the ICSI patients, >90% of oocytes survived in all culture groups, regardless of MAS addition, however MAS (10 or 30 microg/ml) significantly increased the proportion of oocytes maturing in vitro (P < 0.05). The apparent tendency towards improved subsequent development in vitro will require larger numbers of oocytes for evaluation. Oocytes from ICSI patients matured more rapidly in vitro than those from PCO patients. Our results show positive effects of MAS on human oocytes, confirming previous data in mice. This work may have implications for the future clinical application of IVM.

Adult↗
PubMed1999

Nitric oxide synthase expression and steroid regulation in the uterus of women with menorrhagia.

Menorrhagia (excessive menstrual bleeding) is a common clinical problem of unknown aetiology. The free-radical and vasodilator nitric oxide (NO) relaxes the myometrial smooth muscle and is a strong candidate for the cause of excessive blood loss in menorrhagic patients. The aim of this study was to measure NO production in women with and without menorrhagia to detect nitric oxide synthase (NOS) isoforms in uterine cells and to investigate any steroid effects on myometrial NOS expression. We showed for the first time that menorrhagic endometrium produces significantly higher amounts of NOx (the sum of NO(2-) and NO(3-)) than control endometrium (P < 0.01). Inducible NOS (iNOS) protein was detected by immunoblotting in endometrial and myometrial tissue extracts. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) experiments revealed an induction of myometrial smooth muscle endothelial NOS (eNOS) expression by progesterone and 17beta-oestradiol, while myometrial iNOS expression was unaffected by steroid hormones. These results are consistent with the hypothesis that NO plays a role in excessive menstrual bleeding and provide the first evidence on steroid regulation of eNOS in the human non-pregnant uterus.

Adult↗
PubMed1997

The role of endometrium in implantation.

As implantation approaches the different endometrial components demonstrate certain anatomical and molecular changes. Molecules with an effect on uterine receptivity for blastocyst implantation include integrins, leukaemia inhibitory factor (LIF), interleukin-1 (IL-1) and colony stimulating factor-1 (CSF-1). Although over the past 5 years our understanding of the implantation process has improved dramatically, there are still many unanswered questions. Undisputed morphological, biochemical and molecular markers of uterine receptivity that permit quantification of the human implantation window are still unknown. The factors which regulate the expression of integrins, LIF, CSF-1 and IL-1, the mode of action of these molecules and their role in human implantation remain unclear. Only when these questions are answered shall we be able to apply the molecular aspects of implantation to clinical practice.

Blastocyst↗
PubMed1996

Immunohistochemical localization of extracellular matrix proteins in luteal phase endometrium of fertile and infertile patients.

The lack of expression of certain components involved in cell adhesion and migration is believed to contribute to endometrial dysfunction and implantation failure. The purpose of this study was to investigate whether luteal phase endometrium in women with unexplained infertility differs, with respect to specific extracellular matrix (ECM) proteins, from endometrium of normal fertile women. A panel of monoclonal antibodies to collagen type IV, fibronectin and laminin was used to characterize the localization of ECM components in the different endometrial compartments. Precisely timed endometrial biopsies obtained at 4, 7, 10 and 13 days following the luteinizing hormone surge were obtained from 22 normal fertile women (group 1) and 24 women suffering from unexplained infertility (group 2). Paraffin-embedded sections were labelled using the streptavidin-biotin alkaline phosphatase technique. In group 1, collagen type IV, fibronectin and laminin were absent from the luminal epithelium but present in stromal cells and the basement membrane of glands and blood vessels. In group 2, these components were absent from all endometrial regions using equivalent titres of antibody to those used in group 1. This suggests that the endometrium of women with unexplained infertility demonstrates defects in the distribution of certain ECM glycoproteins. A possible consequence of this defect may be implantation failure.

Adult↗
PubMed1995

Endometrial leukocyte subpopulations in women with endometriosis.

The aim of this study was to investigate whether the endometrium of women with endometriosis differs immunologically from the endometrium of normal fertile women. Endometrial biopsies were obtained from 18 normal fertile women who were requesting sterilisation or reversal of sterilisation and 21 infertile women who had laparoscopically diagnosed pelvic endometriosis. The endometrial biopsies were obtained from both groups during the either early, mid or late luteal phase of the menstrual cycle. A panel of 11 monoclonal antibodies and immuno-histochemical techniques were employed to characterise the endometrial stromal leukocytes in frozen sections. Image analysis was used for semi quantitation of leukocytes. In both groups, the number of endometrial granulated lymphocytes (CD56+ CD38+ cells) and macrophages (CD68+ cells) increased significantly between the early and late luteal phase of the menstrual cycle. Compared with fertile controls, women with endometriosis had fewer T-suppressor/cytotoxic (CD8+) cells and endometrial granulated lymphocytes but more T-helper/inducer (CD4+) cells, CD68+ cells and CD16+ cells. None of these differences reached a statistically significant level. This study has shown that the endometrial lymphoid tissue of women with endometriosis does not differ qualitatively or quantitively from that of normal fertile controls. However, functional differences of endometrial leukocytes between the two groups cannot be excluded.

Adult↗
PubMed1995

Human sperm morphology evaluation pre- and post-Percoll gradient centrifugation.

Previous experiments have established a relationship between the morphological characteristics of human spermatozoa and their fertilizing potential in vitro. To assess further the efficiency of Percoll gradient centrifugation (PGC) as a method of sperm selection, we have examined morphological characteristics of spermatozoa from 86 teratozoospermic patients attending Nottingham University Research and Treatment Unit in Reproduction (NURTURE). Patients were divided into groups according to percentage normal morphology in the fresh sample: group A (n = 14), < 5% normal morphology; group B (n = 41), 5-14% normal morphology; and group C (n = 31), > 14% normal morphology. Morphology slides were prepared using Diff Quik staining techniques and evaluated by Kruger strict criteria, under oil immersion, at a magnification of x1000; specific defects, viz. head, neck, cytoplasmic droplets, tail, immature cells, were assessed individually. Following PGC, a sperm sample with enhanced morphology was recovered for group B (P < 0.01) and C (P < 0.005); however, for group A (very severe teratozoospermia) PGC did not select a sample with significantly improved morphological quality. Specific sperm defects affected by PGC were head, neck and immature cells. No significant difference was found for tail abnormalities or cytoplasmic fragments.

Cellular Senescence↗
PubMed1995

A positive correlation between expression of beta 1-integrin cell adhesion molecules and fertilizing ability of human spermatozoa in vitro.

The purpose of this study was to investigate firstly whether beta 1-integrin cell adhesion molecules are expressed by human spermatozoa, and secondly whether there is any relationship between the expression of beta 1-integrin cell adhesion molecules and the fertilizing ability of human spermatozoa in vitro. A total of 50 semen samples were examined. The samples were obtained from the male partners of couples undergoing in-vitro fertilization (IVF) for either unexplained, tubal or male factor infertility. A panel of six monoclonal antibodies against beta 1-integrin cell adhesion molecules and immunohistochemical techniques were used to identify the presence of these molecules on the spermatozoa. The percentage of spermatozoa showing strong immunolabelling with each monoclonal antibody was assessed in each sample. The relationship between these results and the aetiology of infertility and incidence of fertilization was examined. beta 1-Integrins, and primarily the ones with alpha 4-, alpha 5- and alpha 6-chains, were expressed by human spermatozoa. Compared with semen samples from unexplained or male factor infertility patients, samples from tubal infertility patients had a significantly higher (P < 0.05) percentage of spermatozoa expressing adhesion molecules. There was a positive correlation between the expression of alpha 4, alpha 5 and alpha 6 adhesion molecules and the fertilizing ability of spermatozoa. The positive correlation between the presence of certain beta 1-integrin cell adhesion molecules and the fertilizing ability of human spermatozoa suggests that integrins may be putative determinants in egg-sperm recognition and interaction.

Adult↗
PubMed1994

Placental protein 14 in cycles with normal and retarded endometrial differentiation.

The purpose of this study was to investigate whether endometrium with retarded development differs, functionally, from endometrium with normal 'in-phase' development. Precisely timed endometrial biopsies were obtained from 24 women suffering from unexplained infertility at 4, 7, 10 and 13 days following the luteinizing hormone (LH) surge. Frozen sections were labelled with an anti-placental protein (PP) 14 monoclonal antibody using an avidin-biotin peroxidase technique and semi-quantification of endometrial PP14 was performed using a Quantimet 970 image analyser. Serum PP14 and saliva progesterone were measured for each patient. Data were analysed using one- and two-way analysis of variance. Normal and retarded endometrium were identified in 16 (group I) and eight (group II) women respectively. Both groups demonstrated a significant increase of the area of precipitate measured for PP14 from day LH + 4 to LH + 13. However, two-way analysis of variance showed that endometrial PP14 was significantly (P < 0.05) lower in the retarded endometrium group at LH + 10 and LH + 13. Serum PP14 was also significantly lower (P < 0.01) in women with retarded endometrial development at LH + 13. Women with normal endometrial development had a significantly higher (P < 0.05) concentration of cumulative saliva progesterone from LH + 3 to LH + 5. This study indicates that there are functional differences between normal and retarded endometrium. These differences may adversely affect uterine receptivity during implantation and the early placentation stage.

Adult↗
PubMed1994

Lymphoid tissue in the endometrium of women with unexplained infertility: morphometric and immunohistochemical aspects.

The purpose of this study was to investigate whether the endometrium of women with unexplained infertility differs in some immunological aspects from the endometrium of normal fertile women. Endometrial biopsies were obtained from 24 normal fertile women (group I) and 24 women suffering from unexplained infertility (group II) at 4, 7, 10 and 13 days following the luteinizing hormone (LH) surge. Endometrial granulated lymphocytes were assessed morphometrically in 2 microns resin sections. A panel of 11 monoclonal antibodies was employed to characterize the leukocyte subsets in frozen sections. Semi-quantification was performed with a Quantimet 970 image analyser. Data were analysed using one- and two-way analysis of variance. Compared with fertile controls, women with unexplained infertility had significantly lower numbers of CD8+ (T suppressor/cytotoxic) cells at each post-LH date. In contrast, the number of CD4+ (T helper/inducer) cells was significantly higher in group II. Throughout the luteal phase, infertile women had fewer CD56+ cells than normal fertile controls. The volume fraction of endometrium occupied by the nuclei of endometrial granulated lymphocytes did not alter with the cycle stage but the mean nuclear diameter and axial ratio decreased from LH+7 to LH+13. The differences observed in endometrial leukocytic subpopulations between fertile and infertile women may contribute to unexplained infertility probably by affecting the embryonic maternal dialogue during the implantation and early placentation period.

ADP-ribosyl Cyclase↗
PubMed1993

Beta-1 integrin cell adhesion molecules in the endometrium of fertile and infertile women.

In order to investigate whether the endometrium of women with unexplained infertility differs immunologically from the endometrium of normal fertile women, a panel of six monoclonal antibodies was used to characterize the presence of the beta 1-integrins or very-late-activation antigens (VLA) in the different endometrial compartments. Precisely timed endometrial biopsies at 4, 7, 10 and 13 days following the luteinizing hormone surge were obtained from 24 normal fertile women (group I) and 24 women suffering from unexplained infertility (group II). Frozen sections were labelled using an avidin-biotin peroxidase technique. VLA-1, VLA-2 and VLA-3 were present in glandular epithelium, stromal cells and vessels of both groups. VLA-4 was detected in group I but was absent from glandular and surface epithelium of group II. VLA-5 was not present in any of the specimens. VLA-6 was identified primarily in the basement membrane of vessels, glandular and surface epithelium in both patient groups. This study indicates that most beta 1-integrins are present in endometrium throughout the luteal phase of the menstrual cycle. The differences observed between the two groups may contribute to unexplained infertility.

Adult↗
PubMed1992

The endometrial biopsy as a predictive factor of pregnancy rate in women with unexplained infertility.

To investigate whether or not there is any relation between endometrial morphology and subsequent pregnancy rate, 47 couples with unexplained infertility were followed up for 3 years after they had had an endometrial biopsy. Each woman had an LH-timed endometrial biopsy performed in the luteal phase of the cycle. The biopsy was dated chronologically according to the luteinizing hormone (LH) surge and histologically using morphometric criteria. None of the women received any form of treatment in the endometrial biopsy cycle. Of 47 women with unexplained infertility, 36 (76.6%) (Group I) had 'in phase' endometrial development and 11 (23.4%) (Group II) had retarded endometrium. Women with normal endometrial development had a higher pregnancy rate than women with retarded endometrial development (50% vs. 9%; P less than 0.02). The fecundability during treatment cycles was higher in Group I than in Group II (0.051 vs. 0.008; P less than 0.05). In women with 'in phase' endometrium, treatment increased the monthly probability of conception (0.051 vs. 0.006; P less than 0.001). A precisely timed endometrial biopsy should be considered as part of the investigations for women with unexplained reproductive failure, to help determine prognosis.

Adult↗
PubMed1992

Endometrial lymphoid tissue in the timed endometrial biopsy: morphometric and immunohistochemical aspects.

OBJECTIVES: The purpose of this study was to provide a morphometric profile of endometrial granulated lymphocytes and to investigate qualitative and quantitative differences in leukocyte subsets in precisely timed luteal phase endometrial biopsies. STUDY DESIGN: Endometrial biopsies were obtained from 24 normal fertile women at 4, 7, 10, and 13 days after the luteinizing hormone surge. Endometrial granulated lymphocytes were assessed morphometrically in 2 microns resin sections. Eleven monoclonal antibodies were used to characterize leukocytes in frozen sections. Semiquantitation was performed with a Quantimet 970 image analyzer. Data were analyzed with one-way analysis of variance. RESULTS: CD8+ (T suppressor-cytotoxic) cells increased significantly from 4 to 7 days after the luteinizing hormone surge, whereas CD68+ macrophages increased from days 10 to 13. Lymphocytes with an unusual phenotype (CD56+, CD38+, CD2+) increased dramatically after 7 days. The volume fraction of endometrium occupied by the nuclei of endometrial granulated lymphocytes did not alter, but their mean nuclear diameter and axial ratio decreased from days 7 to 13. CONCLUSION: The morphometric findings indicate in situ proliferation of endometrial granulated lymphocytes rather than migration from the peripheral circulation. T lymphocytes, macrophages, and endometrial granulated lymphocytes increase significantly between certain stages of the luteal phase.

Adult↗
PubMed1991

Lectin binding of endometrium in women with unexplained infertility.

OBJECTIVE: To investigate whether peri-implantation phase endometrium in women with unexplained infertility differs from the endometrium of normal fertile women. DESIGN: Assessment of the function of the endometrium by using endometrial biopsy specimens and lectin histochemistry. SETTING: Infertility Clinic, Jessop Hospital for Women, Sheffield, United Kingdom. PATIENTS: Eighteen normal fertile women (group I) and 18 women with unexplained infertility (group II). INTERVENTIONS: Endometrial biopsies were obtained from both groups at 5, 7, and 9 days after the luteinizing hormone (LH) surge. MAIN OUTCOME MEASURES: Five biotinylated lectins, concanavalin A (ConA), wheat germ agglutinin (WGA), soybean agglutinin, Peanut, and Ulex europaeus I were used as analytical probes to study endometrial glycoconjugates. Histochemical staining was performed using the avidin-biotin peroxidase method. The lectin binding by endometrial glands, surface epithelium, stromal cells, and vessels was assessed. RESULTS: In group I, ConA stained the subnuclear glandular cytoplasm, glandular lumen, stroma cells, and surface epithelium. In group II, ConA binding to glandular or surface epithelium was none or equivocal. In group I, WGA bound to glandular cytoplasm and stroma cells on days LH + 5 and LH + 7. In group II, WGA binding was absent in glands but present in stroma. CONCLUSIONS: Reproductive failure of women with unexplained infertility may be associated with defective biosynthesis and distribution of glycoconjugates that subsequently results in an unfavorable endometrial environment during the peri-implantation phase.

Adult↗