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141.
142.
How to use Chlamydia antibody testing in subfertility patients 总被引:1,自引:9,他引:1
Screening for tubal factor subfertility by means of Chlamydia antibody
testing (CAT) was introduced into the initial work-up of subfertile couples
several years ago. The results reported, however, are heterogeneous, and no
uniformity exists in cut-off levels of titres, or in definitions of tubal
factor subfertility. We performed a prospective cohort study to evaluate
the implications of varying the definitions of tubal pathology and of
modifying the cut-off levels on the clinical impact of CAT in predicting
tubal factor subfertility. In 227 consecutive patients who attended our
fertility clinic, the Chlamydia IgG antibody titre was determined and
related to tuboperitoneal abnormalities at laparoscopy as a reference
standard. According to received operating characteristic (ROC) curve
analysis, a titre of 16 is the optimum cut-off level. Increasing the
cut-off level improves specificity and positive likelihood ratio (LR+), at
the expense of sensitivity and negative LR (LR-). Changing the definition
of tubal factor subfertility from unspecified tuboperitoneal abnormalities
into extensive adhesions and/or bilateral distal tubal occlusion improves
LR+, LR- and kappa significantly. We conclude that CAT is more accurate in
predicting severe distal tubal pathology than unspecified tuboperitoneal
abnormalities. Although from a statistical point of view a titre of 16 is
the optimum cut-off level, from a clinical point of view 32 or 64 may be
preferable, depending on the aim of screening and the inception cohort.
相似文献
143.
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
144.
D. M. McKay D. W. Halton C. F. Johnston I. Fairweather C. Shaw 《Parasitology research》1990,76(6):509-517
The localistion and distribution of the cholinergic, serotoninergic and peptidergic components of the nervous system of the frog-lung flukeHaplometra cylindracea have been determined by the application of standard enzyme cytochemical and immunocytochemical techniques to cryostat sections and whole-mount preparations. Cholinesterase activity (ChE), as indicative of acetylcholine, has been demonstrated cytochemically in the CNS and PNS; however, the anterior ganglia were notably unreactive. The occurrence of serotonin was examined by an indirect immunofluorescence technique, and immunoreactivity (IR) was demonstrable in small, paired anterior ganglia and in fine nerve fibres associated with the somatic muscle, cirrus and gonopore. The peptidergic protion of the nervous system was investigated using antisera to 17 mammalian regulatory peptides and the invertebrate peptide FMRFamide, and was visualised by both indirect immunofluorescence and confocal scanning laser microscopy. Positive immunostaining occurred with antisera raised against pancreatic polypeptide (PP), peptide tyrosine tyrosine (PYY), substance P (SP), peptide histidine isoleucine (PHI) and FMRFamide. Immunoreactivity to PP, PYY and FMRFamide was widespread throughout the nervous system and was evident in large, paired anterior ganglia, the dorsal commissure, main nerve tracts and the extensive array of small fibres that constitute the PNS. In contrast, the distribution of nerves immunoreactive to SP and PHI was less apparent, with PHI-IR occurring exclusively within the fibrous neuropile of the ganglia and in fibres of the ventral nerve cord. Results are discussed with respect to the distribution of the various neurochemical elements and their roles as putative neurotransmitters and/or regulatory molecules. 相似文献
145.
In postnatal day 7 rats, a unilateral intrastriatal injection of 12.5 nmol of N-methyl-D-aspartate (NMDA) reproducibly injures the ipsilateral striatum, adjacent hippocampus and overlying cortex. The severity of injury can be quantified by comparing cerebral hemisphere weights in animals sacrificed 5 days after the injection. Co-injection of NMDA and the glycine receptor antagonists kynurenic acid (KYN) or 7-chlorokynurenic acid (7-CKA) reduced the severity of NMDA-induced damage in a dose-dependent fashion. One hundred nmol of KYN with 12.5 nmol of NMDA reduced average % damage from 19.3 +/- 0.9% (n = 9) to 2.3 +/- 0.5% (n = 6), P less than 0.001, ANOVA. Co-injection of 40 nmol of 7-CKA with 12.5 nmol of NMDA (n = 6) reduced average % damage from 17.1 +/- 1.6% (n = 15) to 3.0 +/- 0.6%, P less than 0.001, ANOVA. Concurrent injection of 1000 nmol glycine with 5 nmol NMDA did not increase the extent of NMDA-induced damage. Our results demonstrate that glycine receptor antagonists attenuate NMDA-induced brain injury in vivo. 相似文献
146.
147.
Sanchez AA Johnston DA Myers C Edwards JE Mitchell AP Filler SG 《Infection and immunity》2004,72(1):598-601
Candida albicans must penetrate the endothelial cell lining of the vasculature to invade the deep tissues during a hematogenously disseminated infection. We compared 27 C. albicans mutants with their wild-type parent for their capacity to damage endothelial cells in vitro and cause a lethal infection in mice following tail vein inoculation. Of 10 mutants with significantly impaired capacity to damage endothelial cells, all had attenuated virulence. Therefore, the endothelial cell damage assay can be used as a screen to identify some virulence factors relevant to hematogenously disseminated candidiasis. 相似文献
148.
Luo Ling Xu Daniel W. McVicar Adit Ben-Baruch Douglas B. Kuhns James Johnston Joost J. Oppenheim Ji Ming Wang 《European journal of immunology》1995,25(9):2612-2617
The diversity of monocyte chemotactic protein (MCP)3 target cell types, as well as the capacity of MCP3 to desensitize leukocyte responses to other CC chemokines, suggested that MCP3 may interact with multiple CC chemokine receptors. The purpose of this study is to establish how MCP3 binds and activates monocytes and neutrophils. We show that human monocytes exhibit high-affinity binding for 125I-MCP3 with an estimated Kd of 1–3 nM and about 10000 binding sites/cell. The binding of 125I-MCP3 to monocytes was progressively less well competed by CC chemokines macrophage inflammatory protein (MIP)lα (Kd = 5–10 nM), RANTES (Kd = 5–10 nM), MCP1 (monocyte chemoattractant and activating factor, or MCAF) (Kd = 60 nM) and MIP1β (Kd > 100 nM). On the other hand, unlabeled MCP3 displaced the binding of radiolabeled MIP1α, RANTES, MCP1 and MIP1β as effectively as the isologous CC chemokines. In agreement with the binding data, pretreatment of monocytes with MCP3 completely desensitized the calcium flux in response to MIP1α and RANTES. However, MIP1α and RANTES failed to desensitize the response of monocytes to MCP3. MCP3 and MCP1 partially desensitized each other's effects on monocytes. These binding and cross-desensitization results suggest that MCP3 binds and signals through other binding sites in addition to those shared with MIP1α, RANTES and MCP1. The unidirectional competition for MIP1β binding and signaling by MCP3 suggests the existence of an as-yet unidentified site for MCP3 shared with MIP1β. The existence of another unique binding site(s) for MCP3 was further shown by the failure of any of the other CC chemokines to compete effectively for MCP3 binding on neutrophils. MCP3 in our study was also the only human CC chemokine that consistently chemoattracted neutrophils. These results suggest that MCP3 is a ligand that can bind and activate a broad range of target cells through receptors shared by other CC chemokines as well as its own receptor. 相似文献
149.
150.