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1.
  • A Hulten, Maj, et al. (författare)
  • On the origin of the maternal age effect in trisomy 21 Down syndrome: the Oocyte Mosaicism Selection model
  • 2010
  • Ingår i: Reproduction. - 1470-1626 .- 1476-3990. ; 139:1, s. 1-9
  • Forskningsöversikt (refereegranskat)abstract
    • We have recently documented that trisomy 21 mosaicism is common in human foetal ovaries. On the basis of this observation we propose that the maternal age effect in Down syndrome (DS) is caused by the differential behaviour of trisomy 21 in relation to disomy 21 oocytes during development from foetal life until ovulation in adulthood. in particular, we suggest that trisomy 21 oocytes, lagging behind those that are disomic, may escape the timed pruning of the seven million in foetal life to the 300-400 finally selected for ovulation. The net effect of this preferential elimination will be an accumulation of trisomy 21 oocytes in the ovarian reserve of older women. We here highlight the implications of this Oocyte Mosaicism Selection (OMS) model with respect to the prevalent view that the maternal age effect is complex, dependent on many different biological and environmental factors. We examine conclusions drawn from recent large-scale studies in families, tracing DNA markers along the length of chromosome 21q between parents and DS children, in comparison to the OMS model. We conclude that these family linkage data are equally compatible with the maternal age effect originating from the accumulation of trisomy 21 oocytes with advancing maternal age. One relatively straightforward way to get to grips with what is actually going on in this regard would be to compare incidence of trisomy 21 oocytes (and their pairing configurations) in foetal ovaries with that in oocytes at the meiosis I stage from adult women.
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2.
  • Barranco, Isabel, et al. (författare)
  • Active paraoxonase 1 is synthesised throughout the internal boar genital organs.
  • 2017
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1741-7899. ; 154:3, s. 237-243
  • Tidskriftsartikel (refereegranskat)abstract
    • The paraoxonase type 1 (PON1) is an enzyme with antioxidant properties recently identified in the seminal plasma (SP) of several species, including the porcine. The aims of the present study were to (1) describe the immunohistochemical localisation of PON1 in the genital organs of fertile boars and (2) evaluate the relationship among PON1 activity and high-density lipoprotein cholesterol (HDL-C) concentration in fluids of the boar genital organs. Immunohistochemical analysis demonstrated that PON1 was present in testis (specifically in Leydig cells, blood vessels, spermatogonia and elongated spermatids), epididymis (specifically in the cytoplasm of the principal epithelial cells, luminal secretion and in the surrounding smooth muscle) and the lining epithelia of the accessory sexual glands (cytoplasmic location in the prostate and membranous in the seminal vesicle and bulbourethral glands). The Western blotting analysis confirmed the presence of PON1 in all boar genital organs, showing in all of them a band of 51 kDa and an extra band of 45 kDa only in seminal vesicles. PON1 showed higher activity levels in epididymal fluid than those in SP of the entire ejaculate or of specific ejaculate portions. A highly positive relationship between PON1 activity and HDL-C concentration was found in all genital fluids. In sum, all boar genital organs contributing to sperm-accompanying fluid/s were able to express PON1, whose activity in these genital fluids is highly dependent on the variable HDL-C concentration present.
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3.
  • Bertram, Michael, et al. (författare)
  • Reproduction in a polluted world: implications for wildlife
  • 2020
  • Ingår i: Reproduction. - 1470-1626 .- 1741-7899. ; 160, s. R13–R23-
  • Forskningsöversikt (refereegranskat)abstract
    • Environmental pollution is an increasing problem for wildlife globally. Animals are confronted with many different forms of pollution, including chemicals, light, noise, and heat, and these can disrupt critical biological processes such as reproduction. Impacts on reproductive processes can dramatically reduce the number and quality of offspring produced by exposed individuals, and this can have further repercussions on the ecology and evolution of affected populations. Here, we illustrate how environmental pollutants can affect various components of reproduction in wildlife, including direct impacts on reproductive physiology and development, consequences for gamete quality and function, as well as effects on sexual communication, sexual selection, and parental care. We follow with a discussion of the broader ecological and evolutionary consequences of these effects on reproduction and suggest future directions that may enable us to better understand and address the effects of environmental pollution.
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6.
  • Bourlev, Vladimir, et al. (författare)
  • The relationship between microvessel density, proliferative activity and expression of vascular endothelial growth factor-A and its receptors in eutopic endometrium and endometriotic lesions
  • 2006
  • Ingår i: Reproduction. - : Bioscientifica. - 1470-1626 .- 1476-3990 .- 1741-7899. ; 132:3, s. 501-509
  • Tidskriftsartikel (refereegranskat)abstract
    • Studies were performed to elucidate the possible relationship between microvessel density, proliferative activity and angiogenesis in eutopic endometrium from women with and without endometriosis and peritoneal endometriotic lesions. The question whether changes in these parameters in endometriotic lesions were reflected by the level of vascular endothelial growth factor-A (VEGF-A) in serum and peritonea fluid was also studied. Biopsy specimens of both eutopic endometrium and peritoneal endometriotic lesions from women with endometriosis (n=25) as well as eutopic endometrium from women without endometriosis (n=14) were analysed immunohistochemically regarding microvessel density, proliferative activity, and expression of VEGF-A and its receptors vascular endothelial growth factor receptors 1 and 2 (VEGFR-1 and VEGFR-2) in stroma, glands and blood vessels. The VEGF-A concentration was measured in peritoneal fluid and serum. Secretory phase eutopic endometrium from women with endometriosis had significantly higher microvessel density, expression of VEGF-A in glandular epithelium and VEGFR-2 in endometrial blood vessels than those from women without endometriosis. Endometriotic lesions with high proliferative activity had a higher microvessel density and showed higher vascular expression of VEGFR-2 as well as being accompanied by higher levels of VEGF-A in peritoneal fluid and serum, compared with lesions with low proliferative activity. In conclusion, there seems to be a dysregulation of angiogenic activity in the eutopic endometrium of women with endometriosis and endometriotic lesions with high proliferative activity were accompanied by higher local angiogenic activity and higher levels of VEGF in serum and peritoneal fluid.
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7.
  • Carlsson, IB, et al. (författare)
  • Kit ligand and c-Kit are expressed during early human ovarian follicular development and their interaction is required for the survival of follicles in long-term culture
  • 2006
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 131:4, s. 641-649
  • Tidskriftsartikel (refereegranskat)abstract
    • The receptor tyrosine c-Kit and its cognate ligand, c-Kit ligand (KL, stem cell factor, SCF), are involved in ovarian follicular development in several animal species. We studied the expression of KL and c-Kit usingin situhybridization and immunohistochemistry in donated human ovarian cortical tissue. The KL transcripts were expressed in granulosa cells of primary follicles, whereas the expression of c-Kit was confined to the oocyte and granulosa cells in primary and secondary follicles. We employed an ovarian organ culture using firstly serum-containing and then serum-free medium to study the effects of KL and an anti-c-Kit antibody, ACK2, on the development and survival of ovarian folliclesin vitro. Culture of ovarian cortical slices for 7 days resulted in a 37% increase in the number of primary follicles and a 6% increase in secondary follicles. The proportion of viable follicles decreased in all cultures. The addition of KL (1, 10 and 100 ng/ml) into the culture media did not affect the developmental stages of the follicles or the proportion of atretic follicles. Inclusion of ACK2 (800 ng/ml) in the culture medium significantly increased the proportion of atretic follicles on days 7 (49 vs 28% in control cultures) and 14 (62 vs 38%) of culture. In conclusion, c-Kit and KL are expressed in human ovaries during follicular development. Blocking the c-Kit receptor induces follicular atresia. The KL/c-Kit signaling system is likely to control the survival of human ovarian follicles during early follicular development.
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8.
  • Coward, K., et al. (författare)
  • Phospholipase C zeta, the trigger of egg activation in mammals, is present in a non-mammalian species
  • 2005
  • Ingår i: Reproduction. - : Bioscientifica. - 1470-1626 .- 1476-3990 .- 1741-7899. ; 130:2, s. 157-163
  • Tidskriftsartikel (refereegranskat)abstract
    • The activation of the egg to begin development into an embryo is triggered by a sperm-induced increase in intracellular egg Ca2+. There has been much controversy about how the sperm induces this fundamental developmental event, but recent studies suggest that, in mammals, egg activation is triggered by a testis-specific phospholipase C: PLC zeta. Since the discovery of PLC zeta, it has been unclear whether its role in triggering egg activation is common to all vertebrates, or is confined to mammals. Here, we demonstrate for the first time that PLC zeta is present in a non-mammalian vertebrate. Using genomic and cDNA databases, we have identified the cDNA encoding a PLC zeta orthologue in the domestic chicken that, like the mammalian isoforms, is a testis-specific gene. The chicken PLC zeta cDNA is 2152 bp in size and encodes an open reading frame of 639 amino acids. When injected into mouse oocytes, chicken PLC zeta cRNA triggers Ca2+ oscillations, indicating that it has functional properties similar to those of mammalian PLC zeta. Our findings suggest that PLC zeta may have a universal role in triggering egg activation in vertebrates.
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10.
  • Gavier-Widén, Dolores (författare)
  • Histological and endocrine characterisation of the annual luteal activity in Eurasian lynx (Lynx lynx)
  • 2012
  • Ingår i: Reproduction. - 1470-1626 .- 1741-7899. ; 144, s. 477-484
  • Tidskriftsartikel (refereegranskat)abstract
    • Lynx presents a unique sexual cycle with persistent corpora lutea (CLs) and elevated serum progesterone (P-4) throughout parturition and lactation. In other mammals, CLs normally disintegrate after parturition, therefore the aim of our study was to characterise the annual life cycle of lynx CLs. Ovaries from Eurasian lynxes were obtained from the National Veterinary Institute in Sweden, where tissues from killed lynx were stored at -20 degrees C. Ovaries from 66 animals were weighed; each corpus luteum was segmented for histology and hormone analysis. Ovary and CLs weights were constant throughout the year, peaking during pregnancy. In non-pregnant lynxes, the seasonal level of intraluteal steroids was steady for P-4 (3.2 +/- 1.9 S.D. mu g/g, n = 53) and total oestrogens (18.3 +/- 15.5 S.D. ng/g, n = 53). Within histology slides, structurally intact luteal cells were found throughout the year with the highest incidence in March/April; evidence of luteal regression was predominantly found in post-breeding season. Ovaries from pregnant animals contained two types of CLs. Group A was bigger in size with large luteal cells (P-4, 72.3 +/- 65.4 S.D. mu g/g; oestrogen, 454.0 +/- 52.4 S.D. ng/g). In contrast, group B were smaller, with greater luteal regression and lower steroid concentrations (P-4, 8.3 +/- 2.9 S.D. mu g/g; oestrogen, 31.5 +/- 20.4 S.D. ng/g). Our results suggest that structural luteolysis proceeds throughout the year and into next breeding cycle, resulting in two CLs types on the same ovary. Reproduction (2012) 144 477-484
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11.
  • Guo, Yongzhi, et al. (författare)
  • Adipokines as biomarkers of postpartum subclinical endometritis in dairy cows
  • 2020
  • Ingår i: Reproduction. - 1470-1626 .- 1741-7899. ; 160, s. 417-430
  • Tidskriftsartikel (refereegranskat)abstract
    • Adipokines emerged as regulators of metabolism and inflammation in several scenarios. This study evaluated the relationship between adipokines (adiponectin, chemerin and visfatin) and cytological (subclinical) endometritis, by comparing healthy (without), transient (recovered by 45 days postpartum (DPP)) and persistent (until 45 DPP) endometritis cows (n = 49). Cows with persistent endometritis had higher adiponectin concentrations in plasma (at 21 DPP, P < 0.05 and at 45 DPP, P < 0.01) and in uterine fluid (at 45 DPP, P < 0.001), and higher chemerin concentrations in plasma (P < 0.05) and uterine fluid (P < 0.01) at 45 DPP than healthy cows. Cows with persistent endometritis had higher gene transcription in the cellular pellet of uterine fluid and protein expression in the endometrium of these adipokines and their receptors than healthy cows. Adiponedin plasma concentrations allowed to discriminate healthy from persistent endometritis cows, in 87% (21 DPP) and 98% (45 DPP) of cases, and adiponectin and chemerin uterine fluid concentrations at 45 DPP allowed for this discrimination in 100% of cases. Cows with concentrations above the cutoff were a minimum of 3.5 (plasma 21 DPP), 20.4 (plasma 45 DPP), and 33.3 (uterine fluid 45 DPP) times more at risk of evidencing persistent endometritis at 45 DPP than cows with concentrations below the cutoff. Overall, results indicate a relationship between adipokine signalling and the inflammatory status of the postpartum uterus of dairy cows, evidencing that adipokines represent suitable biomarkers of subclinical endometritis, able to predict the risk of persistence of inflammation.
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12.
  • Humblot, Patrice (författare)
  • Specific expression patterns and cell distribution of ancient and modern PAG in bovine placenta during pregnancye
  • 2013
  • Ingår i: Reproduction. - 1470-1626 .- 1741-7899. ; 146, s. 347-362
  • Tidskriftsartikel (refereegranskat)abstract
    • Pregnancy-associated glycoproteins (PAGs) constitute a multigenic family of aspartic proteinases expressed in the trophoblast of the ruminant placenta. In Bos taurus, this family comprises 21 members segregated into ancient and modern phylogenetic groups. Ancient PAGs have been reported to be synthesized throughout the trophoblastic cell layer whereas modern PAGs are produced by binucleate cells of cotyledons. The aim of this study was to investigate modern and ancient PAGs during gestation in cotyledonary and intercotyledonary tissues. To obtain convincing and innovative results despite the high sequence identity shared between PAGs, we designed specific tools such as amplification primers and antibodies. Using real-time RT-PCR, we described the transcript expression of 16 bovine PAGs. Overall, PAGs are characterized by an increase in their expression during gestation. However, we demonstrated a segregation of modern PACs in cotyledons and of ancient PAGs in the intercotyledonary chorion, except for the ancient PAG2 expressed in cotyledons. By raising specific antibodies against the modern PAG1 and ancient PAG11 and PAG2, we established the expression kinetics of the proteins using western blotting. Immunohistochemistry showed that PAGs were produced by specific cellular populations: PAG1 by binucleate cells in the whole trophoblastic layer, PAG11 was localized in binucleate cells of the intercotyledonary trophoblast and the chorionic plate of the cotyledon, while PAG2 was produced in mononucleate cells of the internal villi of the cotyledon. These results revealed a highly specific regulation of PAG expression and cell localization as a function of their phylogenetic status, suggesting distinct biological functions within placental tissues.
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13.
  • Kannisto, P, et al. (författare)
  • Involvement of local adrenergic receptors in the process of ovulation in gonadotrophin-primed immature rats
  • 1985
  • Ingår i: Journal of Reproduction and Fertility. - : Bioscientifica. - 0022-4251. ; 75:2, s. 62-357
  • Tidskriftsartikel (refereegranskat)abstract
    • Immature female rats were primed with 4 i.u. PMSG at 08:00 h of Day 26. This results in ovulation in the morning of Day 29. The number of ovulations was counted in terms of newly formed corpora lutea in the morning of Day 30. Various adrenergic drugs were delivered into the ovarian bursa bilaterally in the afternoon of Day 27 to study their effect on ovulation. A methyl cellulose gel solution was used as vehicle to minimize leakage from the bursa. Noradrenaline, terbutaline and 4-aminopyridine significantly enhanced the number of corpora lutea compared to control ovaries injected with gel vehicle alone. The effect of terbutaline was counteracted by propranolol. Phentolamine partly blocked the noradrenaline-induced enhancement and the antagonist alone significantly reduced the number of ovulations. The results indicate that stimulation of alpha-adrenergic receptors (probably via actions in the follicle wall) as well as beta-receptors (influencing steroid-producing cells) may interfere with the ovulation process.
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14.
  • Kindahl, Hans (författare)
  • Canine placenta: a source of prepartal prostaglandins during normal and anti progestin-induced parturition
  • 2010
  • Ingår i: Reproduction. - 1470-1626 .- 1741-7899. ; 139, s. 655-664
  • Tidskriftsartikel (refereegranskat)abstract
    • Expression of cyclooxygenase 2 (COX2, now known as PTGS2), prostaglandin E2 synthase (PTGES, PGES), and prostaglandin F2 alpha synthase (PGFS), of the respective receptors PTGFR (FP), PTGER2 (EP2), and PTGER4 (EP4) and of the progesterone receptor (PGR, PR) was assessed by real-time PCR, immunohistochemistry (IHC), or in situ hybridization (ISH) in utero/placental tissue samples collected from three to five bitches on days 8-12 (pre-implantation), 18-25 (post-implantation), and 35-40 (mid-gestation) of pregnancy and during the prepartal luteolysis. Additionally, ten mid-pregnant bitches were treated with the antiprogestin aglepristone (10 mg/kg bw (2 x /24 h)); ovariohysterectomy was 24 and 72 h after the second treatment. Plasma progesterone and 15-ketodihydro-PGF2 alpha (PGFM) concentrations were determined by RIA. Expression of the PGR was highest before implantation and primarily located to the endometrium; expression in the placenta was restricted to the decidual cells. PTGS2 was constantly low expressed until mid-gestation; a strong upregulation occurred at prepartal luteolysis concomitant with an increase in PGFM. PGFS was upregulated after implantation and significantly elevated through early and mid-gestation. PTGES showed a gradual increase and a strong prepartal upregulation. PTGFR, PTGER2, and PTGER4 were downregulated after implantation; a gradual upregulation of PTGFR and PTGER2 occurred towards parturition. ISH and IHC co-localized PGFS, PTGFR, PTGES, and PTGS2 in the trophoblast and endometrium. The changes following application of aglepristone were in the same direction as those observed from mid-gestation to prepartal luteolysis. These data suggest that the prepartal increase of PGF2 alpha results from a strong upregulation of PTGS2 in the fetal trophoblast with the withdrawal of progesterone having a signalling function and the decidual cells playing a key role in the underlying cell-to-cell crosstalk. Reproduction (2010) 139 655-664
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15.
  • Kujala, M, et al. (författare)
  • Expression of ion transport-associated proteins in human efferent and epididymal ducts
  • 2007
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 133:4, s. 775-784
  • Tidskriftsartikel (refereegranskat)abstract
    • Appropriate intraluminal microenvironment in the epididymis is essential for maturation of sperm. To clarify whether the anion transporters SLC26A2, SLC26A6, SLC26A7, and SLC26A8 might participate in generating this proper intraluminal milieu, we studied the localization of these proteins in the human efferent and the epididymal ducts by immunohistochemistry. In addition, immunohistochemistry of several SLC26-interacting proteins was performed: the Na+/H+exchanger 3 (NHE3), the Cl−channel cystic fibrosis transmembrane conductance regulator (CFTR), the proton pump V-ATPase, their regulator Na+/H+exchanger regulating factor 1 (NHERF-1), and carbonic anhydrase II (CAII). Our results show that SLC26A6, CFTR, NHE3, and NHERF-1 are co-expressed on the apical side of the nonciliated cells, and SLC26A2 appears in the cilia of the ciliated cells in the human efferent ducts. In the epididymal ducts, SLC26A6, CFTR, NHERF-1, CAII, and V-ATPase (B and E subunits) were co-localized to the apical mitochondria rich cells, while SLC26A7 was expressed in a subgroup of basal cells. SLC26A8 was not found in the structures studied. This is the first study describing the localization of SLC26A2, A6 and A7, and NHERF-1 in the efferent and the epididymal ducts. Immunolocalization of human CFTR, NHE3, CAII, and V-ATPase in these structures differs partly from previous reports from rodents. Our findings suggest roles for these proteins in male fertility, either independently or through interaction and reciprocal regulation with co-localized proteins shown to affect fertility, when disrupted.
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16.
  • Kumaresan, Arumugam, et al. (författare)
  • Relationship of DNA integrity to HRG C633T SNP and ART outcome in infertile couples
  • 2017
  • Ingår i: Reproduction. - 1470-1626 .- 1476-3990 .- 1741-7899. ; 153:6, s. 865-876
  • Tidskriftsartikel (refereegranskat)abstract
    • The status of sperm DNA fragmentation, protamine deficiency, free thiols and disulphide bonds in colloid-selected samples and its relationship to ART outcome or HRG C633T SNP is not known. The objective of this study was to determine these relationships in spermatozoa from men with male factor or unknown factor infertility (n=118) undergoing in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI). Sperm DNA integrity was analysed by flow cytometry using three fluorescent probes (acridine orange, monobromobimane and chromomycin A3). Principal component analysis (PCA) was used to identify the parameters that most influenced fertility. The relationships of sperm DNA integrity with seminal parameters, HRG C633T SNP and ART outcome were established using ANOVA and t-test. Sperm concentration and yield after preparation accounted for 27% of the total variance; sperm DNA integrity (% DFI and disulphide bonds) accounted for 16% of the variance in men from infertile couples. Sperm % DFI was significantly higher (P < 0.05) in older men than in younger men. A significant difference (P < 0.01) was observed in % DFI between smokers and non-smokers. Sperm % DFI was significantly higher (P < 0.01) in male factor infertility compared to either female factor or unknown factor infertility while free thiols were significantly higher (P < 0.01) in unknown infertility factor. No significant difference was observed between IVF success/failure in any of the seminal parameters studied. There was a tendency for protamine deficiency to be higher and disulphide concentration to be lower in men with HRG 633T. Such assessments may provide additional useful information about the prognosis for ART outcome, although more research is needed before clinical guidelines can be provided.
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17.
  • Lalitkumar, PGL, et al. (författare)
  • Endometrial tumor necrosis factor alpha (TNFalpha) is a likely mediator of early luteal phase mifepristone-mediated negative effector action on the preimplantation embryo
  • 2005
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 129:3, s. 323-335
  • Tidskriftsartikel (refereegranskat)abstract
    • Cytokines and growth factors are important mediators of progesterone-regulated endometrial receptivity and embryo development. Early luteal phase administration of a potent antiprogestin-like mifepristone to the rhesus monkey results in endometrial desynchrony, loss of embryo viability and implantation failure. In the present study, administration of mifepristone (2 mg/kg body weight, s.c.) on day 2 after ovulation resulted in a significant increase (P< 0.01) in the level of tumor necrosis factor α (TNFα) in glandular and vascular compartments of endometrium, and in endometrial secretion and luminal fluid on day 6 after ovulation in the rhesus monkey. There was an associated lag in embryonic development, characterized by delayed mitochondrial maturity, poorly developed junctional complexes, a relative absence of intra-cytoplasmic filaments and a high degree of intra-cellular degenerative features. Exposure of TNFα (0, 0.5, 5, 50 ng/ml) to preimplantation stage mouse embryosin vitroshowed a dose-dependent arrest in growth and development at both morula and blastocyst stages along with ultra-structural features of degeneration similar to those observed in embryos collected from early luteal phase mifepristone-treated monkeys. Thede novosynthesized and released proteins in terms of trichloroacetic acid precipitable35S by morulae and blastocystsin vitroshowed a marked depression following exposure to TNFα compared with control embryos. Based on the above observation and the fact that preimplantation stage embryos express receptors for TNFα, we suggest that increased levels of TNFα in endometrial and luminal compartments around the time of uterine receptivity following early luteal phase administration of mifepristone adversely affect the growth and viability of preimplantation stage embryos.
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19.
  • Morrell, Jane, et al. (författare)
  • Lipid peroxidation, assessed with BODIPY-C-11, increases after cryopreservation of stallion spermatozoa, is stallion-dependent and is related to apoptotic-like changes
  • 2009
  • Ingår i: Reproduction. - 1470-1626 .- 1741-7899. ; 138, s. 55-63
  • Tidskriftsartikel (refereegranskat)abstract
    • Lipid peroxidation (LPO) of stallion spermatozoa was assessed in fresh semen and in samples of the same ejaculates after freezing and thawing. Particular attention was paid to individual differences in the susceptibility to LPO and its possible relationship with freezability. Innate levels of LPO were very low in fresh spermatozoa but increased after thawing, a change that was largely stallion-dependent. The level of LPO in fresh spermatozoa was not correlated with that of the thawed spermatozoa. Negative correlations existed between LPO and intact membranes post-thaw (r= -0.789, P<0.001), and also between LPO and spermatozoa with high mitochondrial membrane potential (Delta psi m) post-thaw (r= -0.689, P<0.001). LPO was also highly and significantly correlated with caspase activity. The correlation between caspase activity in ethidium positive cells and LPO was r=0.772, P<0.001. This LPO is unlikely to represent, per se, a sign of cryopreservation-induced injury, but it is apparently capable of triggering 'apoptotic-like changes' that could result in the sub-lethal cryodamage often seen among surviving spermatozoa. Reproduction (2009) 138 55-63
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21.
  • Rytkönen, Kalle T, et al. (författare)
  • Cell type markers indicate distinct contributions of decidual stromal cells and natural killer cells in preeclampsia.
  • 2022
  • Ingår i: Reproduction (Cambridge, England). - 1741-7899. ; 164:5, s. V9-V13
  • Tidskriftsartikel (refereegranskat)abstract
    • Preeclampsia is a common serious disorder that can occur during pregnancy. This study uses integrative analysis of preeclampsia transcriptomes and single-cell transcriptomes to predict cell type-specific contributions to preeclampsia.Preeclampsia is a devastating pregnancy disorder and a major cause of maternal and perinatal mortality. By combining previous transcriptomic results on preeclampsia with single-cell sequencing data, we here predict distinct and partly unanticipated contributions of decidual stromal cells and uterine natural killer cells in early- and late-onset preeclampsia.
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22.
  • Sengupta, J, et al. (författare)
  • Immunoneutralization of vascular endothelial growth factor inhibits pregnancy establishment in the rhesus monkey (Macaca mulatta)
  • 2007
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 133:6, s. 1199-1211
  • Tidskriftsartikel (refereegranskat)abstract
    • Maternal endometrial vascular endothelial growth factor (VEGF) is considered important in blastocyst implantation. However, there is no direct evidence to support this conjecture in the primate. In the present study, we have examined this hypothesis by testing whether immunoneutralization of VEGF during the peri-implantation stage of gestation affects embryo implantation in the rhesus monkey. Adult female animals (n = 36) during mated ovulatory cycles were randomly assigned to one of the experimental groups treated subcutaneously with either isotype-matched mouse immunoglobulin (group 1: control, n = 8) or monoclonal mouse antibody against VEGF-A (anti-VEGF Mab; group 2: 10 mg on day 5 after ovulation, n = 8; group 3: 20 mg on day 5 after ovulation, n = 8; group 4: 10 mg on day 10 after ovulation, n = 4; group 5: 10 mg on days 5 and 10 after ovulation, n = 8). Anti-VEGF Mab-treated animals in groups 2–4 did not show any marked inhibition in pregnancy establishment. On pooled analysis, however, anti-VEGF Mab administration in groups 2–5 (n = 28) resulted in a significant (P < 0.04) decline in the number of viable term pregnancy when compared with control animals. The observed difference was explained by the fact that 10 mg anti-VEGF Mab given to each animal on days 5 and 10 after ovulation in group 5 (n = 8) inhibited pregnancy establishment significantly (P < 0.02) when compared with control group 1. There was no significant change in serum concentrations of estradiol-17β, progesterone, and free VEGF among groups. Furthermore, animals treated with anti-VEGF Mab (n = 8) as in group 5 revealed marked decrease in immunoreactive VEGF, fms-like tyrosine kinase-1, and kinase-insert domain region in trophoblast cells associated with shallow uterine invasion on day 13 of gestation when compared with samples from control group animals (n = 8). Thus, VEGF action is required for successful blastocyst implantation in the rhesus monkey.
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23.
  • Sengupta, J, et al. (författare)
  • Nitric oxide in blastocyst implantation in the rhesus monkey
  • 2005
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 130:3, s. 321-332
  • Tidskriftsartikel (refereegranskat)abstract
    • Successful blastocyst implantation depends on the interaction between cells of maternal endometrium and conceptus, as well as adequate blood supply to the site of blastocyst implantation. Nitric oxide (NO) generally plays a significant role in the local regulation of vascular physiology in a variety of mammalian tissue systems, however, its role in blastocyst implantation and placentation in the primate is not known. The aim of the present study was to examine: (i) NADH-diaphorase activity and expression of three isoforms of nitric oxide synthase (NOS), namely endothelial NOS (eNOS), inducible NOS (iNOS) and neuronal NOS (nNOS) in pre-implantation stage monkey embryos, morula (n= 4) and blastocyst (n= 10), as well as, in different compartments of conceptus and maternal endometrium at primary implantation sites during lacunar (n= 6) and villous (n= 9) stages of placentation in the rhesus monkey, and (ii) the potential anti-nidatory effect of vaginal administration of NOS inhibitor during the peri-implantation period of conception cycles in rhesus monkeys. Pre-implantation stage blastocysts exhibited marked NADPH-diaphorase activity along with immunopositive iNOS mainly in the inner cell mass. During the lacunar stage, marked eNOS expression was observed in cytotrophoblast cells lining the embryonic cavity. However, cytotrophoblast cells lining villi, forming columns, and constituting anchoring villi expressed all the three isoforms of NOS in villous placenta stage tissue. During the lacunar stage, eNOS and iNOS protein expressions were observed in epithelial and decidual cells of endometrium. As gestation advanced, mRNAs for all three isoforms of NOS were observed to increase in epithelial and decidual cells, however, with no marked change in protein expression. Vaginal administration of a NOS inhibitor (NG-nitro-l-arginine methyl ester, L-NAME, 4, 6, and 8 mg/kg body weight or aminoguanidine, AG, 4 mg/kg body weight) during days 6 to 12 after ovulation resulted in pregnancy failure in a higher number of animals (L-NAME: 8 confirmed pregnancies in 25 animals; AG: 2 confirmed pregnancies in 8 animals) compared with control animals (5 pregnancies in 7 animals). It appears that NO may play an important role in the establishment of pregnancy in the rhesus monkey.
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24.
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25.
  • Setchell, BP, et al. (författare)
  • Reduction of long-term effects of local heating of the testis by treatment of rats with a GnRH agonist and an anti-androgen
  • 2001
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 122:2, s. 255-263
  • Tidskriftsartikel (refereegranskat)abstract
    • Heating the testes of anaesthetized adult rats to 43 degrees C for 30 min in a waterbath was followed by a large decrease in testis and epididymis mass and number of spermatozoa 35 days later. These parameters had recovered to some extent, but not completely, by days 70 and 97 after heating, but had decreased again in rats examined on day 182. There were no consistent effects of heating on androgen status, as determined by the concentrations of testosterone in blood and testis fluids, or by seminal vesicle mass, and interstitial fluid volume was increased in the heated testes. Treatment of rats with an implant of a GnRH agonist and daily injections of an anti-androgen for 14 days (sufficient in itself to cause large temporary decreases in tissue mass, number of spermatozoa and androgen status) did not reduce the initial decrease in testis mass or number of spermatozoa seen after heating, but reduced the later decreases in mass and number of spermatozoa significantly. These findings indicate that, as well as causing damage to spermatocytes and spermatids, as previously reported, heating also reduces the ability of spermatogonia to repopulate the seminiferous tubules at longer intervals after heating. Furthermore, it appears that this effect on the spermatogonia can be reduced by treating the animals with a GnRH agonist and anti-androgen, a treatment similar to that shown by other authors to improve recovery of the testis from irradiation or drug treatment.
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26.
  • Skottman, H, et al. (författare)
  • Culture conditions for human embryonic stem cells
  • 2006
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 132:5, s. 691-698
  • Tidskriftsartikel (refereegranskat)abstract
    • Human embryonic stem cell (hESC) lines have been derived and cultured in variable conditions. The idea behind derivation of hESC lines is to use them in human cell transplantation after differentiation, but already now these cells are widely used for research purposes. Despite similarities among the established lines, important differences have been reported between them, and it has been difficult to compare the results obtained using different lines. Recent optimization of hESC culture conditions has moved from cultures on mouse embryonic fibroblasts (MEFs) in fetal bovine serum-containing medium towards feeder-free culture methods using more defined animal substance-free cultures. The aim has been to establish robust and cost-effective systems for culturing these cells and eliminate the risk of infection transmitted by animal pathogens and immunoreactions caused by animal substances in cell cultures before clinical treatment. It is important to take these modifications into account when carrying out research using these cells. It is known that culture conditions influence gene expression and, hence, probably many properties of the cells. Optimization and standardization of culture methods is needed for research as well as for clinical purposes.
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27.
  • Stronati, A., et al. (författare)
  • Relationships between sperm DNA fragmentation, sperm apoptotic markers and serum levels of CB-153 and p,p '-DDE in European and Inuit populations
  • 2006
  • Ingår i: Reproduction. - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 132:6, s. 949-958
  • Tidskriftsartikel (refereegranskat)abstract
    • Persistent organochlorine pollutants (POPs) are suspected to interfere with hormone activity and the normal homeostasis of spermatogenesis. We investigated the relationships between sperm DNA fragmentation, apoptotic markers identified on ejaculated spermatozoa and POP levels in the blood of 652 adult males (200 Inuits from Greenland, 166 Swedish, 134 Polish and 152 Ukrainian). Serum levels of 2, 2', 4, 4', 5, 5'-hexachlorobiphenyl (CB-153), as a proxy of the total POP burden, and of 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE), as a proxy of the total DDT exposure were determined. Sperm DNA fragmentation was measured by using the TUNEL assay, whereas immunofluorescence methods were utilized for detecting proapoptotic (Fas) and anti-apoptotic (Bcl-xL) markers. Both TUNEL assay and apoptotic markers were statistically differed across the four populations. No correlation between neither sperm DNA fragmentation nor apoptotic sperm parameters and the large variations in POPs exposure was observed for the separate study groups. However, considering the European populations taken together, we showed that both %TUNEL positivity and Bcl-xL were related to CB-153 serum levels, whereas our study failed to demonstrate any relations between DDE and %TUNEL positivity and apoptotic sperm biomarkers (Fas and Bcl-xL) in any region or overall regions. These results suggest that CB-153 and related chemicals might alter sperm DNA integrity and Bcl-xL levels in European adult males, but not in the highly exposed Inuit men. Additional issues (genetic background, lifestyle habits and characterization of total xeno-hormonal activities) need to he investigated in order to fully assess the population variations observed.
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28.
  • Sukjumlong, S, et al. (författare)
  • Immunohistochemical studies on the progesterone receptor (PR) in the sow uterus during the oestrous cycle and in inseminated sows at oestrus and early pregnancy
  • 2005
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 129:3, s. 349-359
  • Tidskriftsartikel (refereegranskat)abstract
    • Physiological changes in the sow uterus involve the regulation by progesterone and its receptor proteins (PR). Therefore, the aim of the present study was to investigate the localization of PR during different stages of the oestrous cycle and in inseminated sows during early pregnancy by use of immunohistochemistry. Uterine samples were collected from cyclic and inseminated sows at different stages of the oestrous cycle and early pregnancy. The samples were fixed in 10% formaldehyde and embedded in paraffin. Immunohistochemistry was done by use of a mouse monoclonal antibody to PR. The highest PR immunostaining in the surface epithelium was observed at oestrus/5–6 h after artificial insemination (AI) and early dioestrus/70 h after AI. In the glandular epithelium, the highest level of PR was found at oestrus with the lowest at late dioestrus/d 19. Higher levels of PR were observed in inseminated groups compared with cyclic sows. In the myometrium, a high level of PR was found at oestrus, while stromal PR cells were constantly present throughout the oestrous cycle and at different stages of early pregnancy. In conclusion, this study shows that the immunopresence of PR in the sow uterus differed between uterine compartments at the same reproductive stage. Differences were also found for some uterine compartments between cyclic and inseminated/early pregnant sows. The relatively consistent immunostaining of PR in the stroma strengthens a stromal role in the regulation of physiological activities in the sow uterus during the oestrous cycle as well as early pregnancy.
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29.
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30.
  • Sundfeldt, Karin, 1962, et al. (författare)
  • E-cadherin-catenin complex in the rat ovary: cell-specific expression during folliculogenesis and luteal formation.
  • 2000
  • Ingår i: Journal of reproduction and fertility. - : Bioscientifica. - 0022-4251. ; 118:2, s. 375-85
  • Tidskriftsartikel (refereegranskat)abstract
    • The cadherins and their cytoplasmic counterparts, the catenins, form the adherens junctions, which are of importance for tissue integrity and barrier functions. The development and maturation of the ovarian follicle is characterized by structural changes, which require altered expression or function of the components involved in cell-cell contacts. The present study examined the cell-specific localization and temporal expression of epithelial cadherin (E-cadherin) and alpha- and beta-catenin during follicular development, ovulation and corpus luteum formation in the immature gonadotrophin- and oestrogen-stimulated rat ovary. Immunohistochemistry and immunoblotting demonstrated the expression of E-cadherin in theca and interstitial cells of immature ovaries before and after injection of equine chorionic gonadotrophin (eCG). E-cadherin was not detected in granulosa cells, except in the preantral follicles located to the inner region of the ovary. The content of E-cadherin in theca and interstitial cells decreased after an ovulatory dose of hCG. Granulosa cells of apoptotic follicles did not express E-cadherin. Oestrogen treatment (diethylstilboestrol) of immature rats for up to 3 days did not result in a measurable expression of E-cadherin in granulosa cells. alpha- and beta-catenin were expressed in all ovarian compartments. The concentration of beta-catenin was constant during the follicular phase, whereas the content of alpha-catenin decreased in granulosa cells after treatment with diethylstilboestrol or hCG. The expression of alpha-catenin was also reduced in theca and interstitial cells after hCG. alpha- and beta-catenin were present in most ovarian cells at all stages of folliculogenesis. Therefore, the catenins have the potential to associate with different members of the cadherin family and to participate in the regulation of cytoskeletal structures and intracellular signalling. The restricted expression of E-cadherin in granulosa cells of preantral follicles indicates a role in the recruitment of these follicles to subsequent cycles. The specific decrease of alpha-catenin in granulosa cells and the reduction of both alpha-catenin and E-cadherin in theca cells of ovulatory follicles might reflect some of the molecular changes in cell-cell adhesion associated with ovulation and luteinization.
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31.
  • Xu, H., et al. (författare)
  • Sperm arylsulfatase A binds to mZP2 and mZP3 glycoproteins in a nonenzymatic manner
  • 2012
  • Ingår i: Reproduction. - 1741-7899 .- 1470-1626. ; 144:2, s. 209-19
  • Tidskriftsartikel (refereegranskat)abstract
    • We have shown previously that sperm surface arylsulfatase A (ASA) of mouse, pig, and human is involved in sperm-egg zona pellucida (ZP) binding. By treating capacitated mouse sperm with A23187 to induce the acrosome reaction, we demonstrated by immunoblotting that ASA also existed in the acrosomal content and on the inner acrosomal membrane. Since mZP2 and mZP3 are known as sperm receptors, whereas mZP1 as a cross-linker of mZP2/mZP3, we determined whether purified ASA bound to mZP2 and mZP3 selectively. The three mZP glycoproteins were purified from solubilized ovarian ZP by size exclusion column chromatography. Immuno-dot blot analyses revealed that purified sperm ASA bound to mZP2 at the highest level followed by mZP3, whereas the binding of ASA to mZP1 was minimal. The results confirmed the physiological significance of sperm ASA in the ZP binding process. The binding of ASA to mZP2 and mZP3 was, however, not dependent on the active site pocket amino acids, Cys69, Lys123, and Lys302, which are pertinent to the capturing of an arylsulfate substrate, since ASA mutant with Ala substitution at these three residues still bound to mZP2 and mZP3. The availability of the active site pocket of ASA bound to the ZP suggested that ASA would still retain enzymatic activity, which might be important for subsequent sperm penetration through the ZP.
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32.
  • Zarnani, AH, et al. (författare)
  • Kinetics of murine decidual dendritic cells
  • 2007
  • Ingår i: Reproduction (Cambridge, England). - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 133:1, s. 275-283
  • Tidskriftsartikel (refereegranskat)abstract
    • Dendritic cells (DCs) are professional antigen presenting cells (APC) capable of induction of primary immune responses as well as immunologic tolerance. Myeloid and lymphoid subsets of murine DCs are able to shift cytokine responses of T cells toward Th2 and Th1 profiles respectively. Thus, DCs would be suitable candidates to mediate the balance of maternal immune responses to conception. We analyzed pregnancy-related variations in uterus and splenic DCs in a murine model. C57BL/6-mated Balb/c female mice with vaginal plugs were scarified at early, middle, and late pregnancy. Frozen sections of uterus and spleen at each stage of pregnancy were immunostained with CD11c- and MHC-II-specific antibodies. Two-color immunohistochemistry was also carried out using anti-CD11c and one of the antibodies against CD11b, CD8α, CD86, and DEC-205. Using morphometric analysis, the average density of DCs and relative percentage of myeloid (CD11c+, CD11b+) and lymphoid DCs (CD11c+, CD8a+) were determined at each stage. Our results showed that DCs are present throughout the pregnancy in decidua. The average density of decidual DCs at early pregnancy was significantly higher relative to middle and late gestation or to those of endometrial DCs of non-pregnant mice. Interestingly, the average density of decidual and splenic DCs, followed the same variations at different stages of pregnancy. The relative percentage of decidual lymphoid DCs (LDC) was significantly higher at mid-gestation when compared with other stages of pregnancy or non-pregnant mice. Inversely, the frequency of myeloid DCs (MDC) and the MDC/LDC ratio were statistically lower at the middle stage of pregnancy. A majority of decidual DCs expressed MHC-II and CD86. At early pregnancy, DCs were more concentrated subadjacent to the luminal epithelial layers, whereas at mid-or late gestation, DCs were randomly distributed in the stroma and around the epithelium. Mid-pregnancy period was a critical point with regard to splenic DCs kinetics, as both the average density of DCs and the frequency of MDCs decreased significantly when compared with early or late pregnancy, although the relative percentage of splenic LDCs did not change. Our data suggest that the balance of MDC and LDC is finely tuned throughout pregnancy, pointing an eminent immunoregulatory role of DCs in the maintenance of pregnancy.
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33.
  • Zhang, Hua, et al. (författare)
  • Combating ovarian aging depends on the use of existing ovarian follicles, not on putative oogonial stem cells
  • 2013
  • Ingår i: Reproduction. - : Bioscientifica. - 1470-1626 .- 1741-7899. ; 146:6
  • Tidskriftsartikel (refereegranskat)abstract
    • Ovarian aging is characterized by both a reduction in egg quality and a drastic reduction in the number of ovarian follicles. It has been generally accepted for 60 years that a fixed population of primordial follicles is established in the ovaries during early life, and in most mammalian species, oocytes cannot renew themselves in postnatal or adult life. This dogma, however, has been challenged over the past decade. In this review, we summarize the recent studies on primordial follicles and putative oogonial stem cells and discuss what resources in the ovary might be more reliable and promising source tools for combating ovarian aging.
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