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31.
Anxiety during pregnancy and fetal attachment after in-vitro fertilization conception 总被引:3,自引:4,他引:3
McMahon CA; Ungerer JA; Beaurepaire J; Tennant C; Saunders D 《Human reproduction (Oxford, England)》1997,12(1):176-182
The aim of this study was to compare 70 couples who had conceived by in-
vitro fertilization (IVF) with 63 matched controls for the prevalence of
anxiety and quality of attachment to the baby during pregnancy. Results for
mothers showed no group differences using a global measure of anxiety, the
Spielberger State-Trait Anxiety Inventory. However, pregnancy-specific
measures revealed significantly higher levels of anxiety in IVF mothers
about the survival and normality of their unborn babies, about damage to
their babies during childbirth and about separating from their babies after
birth. When IVF mothers were differentiated according to the number of
treatment cycles, more differences in anxiety level were revealed, with
most increases occurring in mothers who had experienced two or more
treatment cycles. IVF fathers did not differ from controls on the global
anxiety measure. No data on pregnancy-specific anxiety were available for
fathers. Neither IVF mothers nor IVF fathers differed from controls on
measures of attachment to the baby during pregnancy. Results are discussed
in the context of the need for researchers to employ differentiated and
issue-specific measures to identify concerns that may be unique to IVF
couples. Clinical implications regarding the need for psychological support
during pregnancy are also discussed.
相似文献
32.
Changes in the morphology of viscacha Sertoli cells were studied during the annual reproductive cycle. Sertoli cells exhibited marked nuclear and cytoplasmic changes. Seasonal variation in nuclear size and shape, chromatin texture, and nucleolus characteristics was observed. The seasonal patterns of the volume densities of the endoplasmic reticulum (ER), mitochondria, Golgi complex, dense bodies and lipid inclusions were distinct. Morphometric analysis revealed that the Golgi complex is the organelle most sensitive to seasonal change. It declined drastically in the regressed testes and its recovery was slow. The ER and mitochondria exhibited seasonal variations in their pattern and content, that was minimal during winter. In contrast, an accumulation of lipid and dense bodies, such as primary and secondary lysosomes, accompanied the spermatogenic arrest. The volume densities of both organelles were maximum during the restoration of spermatogenesis. The length and organization of the inter-Sertoli junctions also changed with the reproductive cycle. The Sertoli cell number per tubular cross section decreased significantly during the testicular regression, coincident with the presence of Sertoli cells with marked signs of involution. The degree of regression and recovery exhibited by the viscacha Sertoli cells was closely related to that shown by the associated germ cells. Therefore, seasonal endocrine fluctuations and local factors could be involved in the regulation of the morphological and functional characteristics of the viscacha Sertoli cells. These hormonal fluctuations are synchronized by the photoperiod through the pineal gland and its hormone, melatonin. 相似文献
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Wilkowsky SE Farber M Echaide I Torioni de Echaide S Zamorano PI Dominguez M Suarez CE Florin-Christensen M 《Molecular and biochemical parasitology》2003,127(2):133-141
The search for vaccine candidates against bovine babesiosis caused by Babesia bovis is greatly focused on the identification of merozoite surface-exposed antigens that are widely conserved, functionally relevant and immunodominant in cattle protected against B. bovis infections. We have recently identified msa-2c, a member of the B. bovis variable merozoite surface antigen (VMSA) gene family, which in contrast to other members, appears to be highly conserved among geographically distant B. bovis strains. In this study, we further investigated the potential of the msa-2c gene product as diagnostic and vaccine candidate for bovine babesiosis. RT-PCR studies demonstrated that MSA-2c is transcribed in merozoites of the Argentine R1A strain. In addition, antibodies against R1A recombinant MSA-2c reacted in immunoblots with a single protein of approximately 30kDa in B. bovis merozoite extracts from both R1A and Australian "S" strains, demonstrating translation of this protein in these two strains and conservation of B-cell epitopes between them. These antibodies reacted with the cell surface of R1A merozoites in fixed immunofluorescence assays, indicating the surface localization of MSA-2c. This localization was confirmed by live immunofluorescence studies in two different strains, R1A and S2P. These results also demonstrate the conservation of MSA-2c surface-exposed B-cell epitopes between these two strains. Sera from cattle either naturally or experimentally infected with Argentine strains of B. bovis specifically recognized rMSA-2c in immunoblots, reinforcing the idea that B-cell epitopes in rMSA-2c are widely conserved among field strains of B. bovis. Furthermore, our results show that these B-cell epitopes are highly immunogenic, suggesting that MSA-2c may be a useful diagnostic tool for the detection of bovine babesiosis by B. bovis. Experimental vaccination of five bovines with rMSA-2c resulted in elicitation of high specific anti-rMSA-2c IgG titers, with similar amounts of IgG(1) and IgG(2) produced. Importantly, bovine anti-rMSA-2c antibodies were able to neutralize in vitro bovine erythrocyte invasion by R1A merozoites suggesting a significant functional role for MSA-2c. Taken together these results postulate MSA-2c as a candidate for the development of novel tools for improved control of bovine babesiosis. 相似文献
36.
Increasing trend of Cesarean deliveries in HIV-infected women in the United States from 1994 to 2000
Dominguez KL Lindegren ML D'Almada PJ Peters VB Frederick T Rakusan TA Ortiz IR Hsu HW Melville SK Sadek R Fowler MG;Pediatric Spectrum of HIV Disease Consortium 《Journal of acquired immune deficiency syndromes (1999)》2003,33(2):232-238
BACKGROUND: Meta-analysis and randomized clinical trial results reported in June 1998 indicated a significant reduction in perinatal HIV transmission rates among mothers undergoing a cesarean section (C-section). OBJECTIVE: The objective of this study was to examine recent trends in and factors associated with C-section deliveries among HIV-infected women in the United States. DESIGN: A multisite pediatric medical record review of a cohort of HIV-exposed and HIV-infected infants in the Pediatric Spectrum of HIV Disease (PSD) Cohort study (n = 6467) and the national Pediatric HIV/AIDS Reporting System (HARS) (n = 8,306) was conducted. SETTING/PATIENTS: All infants born between 1994 and 2000 to HIV-positive mothers referred to the PSD study or to a Pediatric HARS hospital or clinic site were enrolled. RESULTS: The proportion of deliveries by C-section was steady at about 20% from 1994 through June 1998. From July 1998 through December 2000, this proportion increased to 44% in the PSD study and to nearly 50% in the Pediatric HARS. On analysis by multiple logistic regression, delivery of infants by C-section was associated with the release of study results (OR = 2.83), delivery in four PSD sites in reference to Texas (OR: 2.02-1.43), having private medical care reimbursement (OR = 1.62), and having maternal prenatal care (OR = 1.43). CONCLUSIONS: The PSD and Pediatric HARS data demonstrate a sharp increase in C-section rates mainly among HIV-infected women in the United States after the release of the meta-analysis and randomized clinical trial results in 1998. This finding highlights the rapid impact of study results on obstetric practice. It underscores the critical role of prenatal care in offering perinatal interventions such as scheduled C-section when indicated to reduce the likelihood of HIV transmission. 相似文献
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Morphological studies have shown that macrophages and microglia undergo
apoptosis in the central nervous system (CNS) in acute experimental
autoimmune encephalomyelitis (EAE) in the Lewis rat. To assess the relative
levels of macrophage and microglial apoptosis, and the molecular mechanisms
involved in this process, we used three-colour flow cytometry to identify
CD45lowCD11b/c+ microglial cells and CD45highCD11b/c+ macrophages in the
inflammatory cells isolated from the spinal cords of Lewis rats 13 days
after immunization with myelin basic protein (MBP) and complete Freund's
adjuvant. Simultaneously, we analyzed the DNA content of these cell
populations to assess the proportions of cells undergoing apoptosis and in
different stages of the cell cycle or examined their expression of three
apoptosis- regulating proteins, i.e. Fas (CD95), Fas ligand (FasL) and
Bcl-2. Microglia were highly vulnerable to apoptosis and were
over-represented in the apoptotic population. Macrophages were less
susceptible to apoptosis than microglia and underwent mitosis more
frequently than microglia. The different susceptibilities of microglia and
macrophages to apoptosis did not appear to be due to variations in Fas,
FasL or Bcl- 2 expression, as the proportions of microglia and macrophages
expressing these proteins were similar, and were relatively high.
Furthermore, in contrast to T cell apoptosis, apoptosis of
microglia/macrophages did not occur more frequently in cells expressing Fas
or FasL, or less frequently in cells expressing Bcl-2. These results
indicate that the apoptosis of microglia and CNS macrophages in EAE is not
mediated through the Fas pathway, and that Bcl-2 expression does not
protect them from apoptosis. Expression of FasL by macrophages and
microglia may contribute to the pathogenesis and immunoregulation of EAE
through interactions with Fas+ oligodendrocytes and Fas+ T cells. The high
level of microglial apoptosis in EAE indicates that microglial apoptosis
may be an important homeostatic mechanism for controlling the number of
microglia in the CNS following microglial activation and proliferation.
相似文献
39.