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41.
42.
Role of NK cells and gamma interferon in transplacental passage of Toxoplasma gondii in a mouse model of primary infection 总被引:7,自引:0,他引:7
Abou-Bacar A Pfaff AW Georges S Letscher-Bru V Filisetti D Villard O Antoni E Klein JP Candolfi E 《Infection and immunity》2004,72(3):1397-1401
Protective immunity in mice infected with Toxoplasma gondii is mainly mediated by NK cells, CD4 and CD8 T cells, and type 1 cytokines, such as gamma interferon (IFN-gamma). To clarify the roles of NK cells and IFN-gamma in protection against primary congenital toxoplasmosis, we used recombination activating gene 2 knockout (RAG-2(-/-)) mice, which lack T and B lymphocytes, in comparison with the wild-type BALB/c model. RAG-2(-/-) mice had a significantly lower risk of fetal toxoplasmosis than BALB/c mice (25 versus 63.9%; P = 0.003). This protection was associated with an increased number of maternal NK cells, IFN-gamma secretion by spleen cells, and decreased parasitemia. In the RAG-2(-/-) mice, NK cell depletion increased both the rate of fetal infection, to 56.5% (P = 0.02), and the blood parasite burden. Conversely, in the BALB/c mice, this treatment did not modify maternofetal transmission or the blood parasite burden. Neutralization of IFN-gamma in both infected RAG-2(-/-) and BALB/c mice decreased congenital Toxoplasma transmission, contrasting with an exacerbation of maternal infection. These data suggest that a partially protective immunity against congenital toxoplasmosis is achieved due to the increased number of NK cells in RAG-2(-/-) mice. However, it seems that IFN-gamma enhances, directly or indirectly, the transplacental transmission. 相似文献
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M. Canonaco L. H. O'Connor D. W. Pfaff B. S. McEwen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1989,75(3):644-652
Summary The levels of gamma amino butyric acid (GABAA) receptors (i.e. 3H-Muscimol binding sites) were determined by quantitative neurotransmitter receptors autoradiography in ovariectomized (OVX), OVX-estradiolo (E), OVX-progesterone (P), OVX-E+P, diazepam (DZ) and DZ + Ro15-1788 treated female hamsters.The various hormonal treatments altered 3H muscimol binding in many brain areas, whereas DZ and DZ + Ro15-1788 had little influence on GABAA receptor levels at the onset of the blocked aggressive behavioral activity. For example, E, P and E+P all significantly increased 3H muscimol binding in medial preoptic area, ventromedial hypothalamic nuclei, and vertical diagonal bandmedial septal nucleus, whereas P treatment increased binding in the caudate-putamen and decreased it in reuniens nucleus of the thalamus. E and E+P treatments increased 3H muscimol binding in the corticomedial amygdala nucleus and hippocampus. Diazepam treatment decreased the GABAA receptor binding in the caudate-putamen and basolateral amygdala, while having no effect in the other brain regions where hormone treatment was effective. In vitro incubation of brain sections with micromolar concentrations of E or P did not change muscimol binding. These results suggest that ovarian steroids, and benzodiazepines to a lesser extent, modulate 3H muscimol binding but do so in different brain regions. The hormone effects on 3H muscimol binding in the critical reproductive centres at a time period that coincides with the onset of its behavioral effect is consistent with a genomic controlled activity. 相似文献
47.
Nomura M Akama KT Alves SE Korach KS Gustafsson JA Pfaff DW Ogawa S 《Neuroscience》2005,130(2):445-456
We examined the distribution of estrogen receptor (ER)-alpha and ER-beta immunoreactive (ir) cells in the dorsal (DRN) and median/paramedian (MPRN) raphe nuclei in male mice. ER-alpha ir neurons were scattered across the three subdivisions (ventral, dorsal, and lateral) of the DRN and the MPRN. Robust ER-beta ir cells were observed throughout the raphe nuclei, and were particularly abundant in the ventral and dorsal subdivisions of the DRN. Using dual-label immunocytochemistry for ER-alpha or ER-beta with tryptophan hydroxylase (TPH), the rate-limiting enzyme for 5-hydroxytryptamine (5-HT) synthesis, over 90% of ER-beta ir cells exhibited TPH-ir in all DRN subdivisions, whereas only 23% of ER-alpha ir cells contained TPH. Comparisons of ER-alpha knockout (alphaERKO) as well as ER-beta knockout (betaERKO) mice with their respective wild-type (WT) littermates revealed that gene disruption of either ER-alpha or ER-beta did not affect the other ER subtype expression in the raphe nuclei. In situ hybridization histochemistry revealed that there was a small but statistically significant decrease in TPH mRNA expression in the ventral DRN subdivision in betaERKO mice compared with betaWT mice, whereas TPH mRNA levels were not affected in alphaERKO mice. These findings support a hypothesis that ER-beta activation may contribute to the estrogenic regulation of neuroendocrine and behavioral functions, in part, by acting directly on 5-HT neurons in the raphe nuclei in male mice. 相似文献
48.
Medullary reticular stimulation can activate deep back muscle EMG in urethane-anesthetized female rats. Midbrain central gray stimulation can facilitate brainstem reticular control over deep back muscles. Since these deep back muscles lateral longissimus (LL) and medial longissimus (ML) execute the vertebral dorsiflexion of lordosis behavior, and since the motor control hierarchy sketched above parallels lordosis behavior circuitry, we tested the hypothesis that medial hypothalamic lesions (which, in behavioral experiments, decrease lordosis) can also reduce medullary reticular activation of deep back muscle EMG. Urethane-anesthetized rats were tested systematically for amplitude of lateral longissimus (LL) and medial longissimus (ML) EMG responses to electrical stimulus trains applied to the nucleus gigantocellularis (NGC) of the medullary reticular formation, before and after electrolytic lesions of the ventromedial hypothalamus (n = 18) or control sites (n = 30). Bilateral ventromedial hypothalamic lesions were able to greatly reduce EMG responses in LL and ML, often with a time course similar to previous lordosis behavioral results. Surprisingly, lesions at the anterior ventromedial nucleus pole were particularly effective, and may reflect importance of intraventromedial local neurons. Although, on the average, various control lesions were less effective, the ventromedial hypothalamic effect was not unique. For example, it was possible to see an EMG decrease following lesions of the dorsomedial thalamus. Nevertheless, EMG loss was not well correlated with changes in the cortical EEG, and thus does not appear to be a simple consequence of changes in "arousal." In conclusion, it appears that ventromedial hypothalamic neurons can affect medullary reticular control of back muscle EMG, but must share this role with other forebrain elements. 相似文献
49.
Antiphospholipid antibodies and the outcome of pregnancy after the first in-vitro fertilization and embryo transfer cycle 总被引:1,自引:1,他引:1
Balasch J; Creus M; Fabregues F; Civico S; Reverter JC; Carmona F; Tassies D; Vanrell JA 《Human reproduction (Oxford, England)》1998,13(5):1180-1183
Increased antiphospholipid antibody prevalence has been demonstrated by a
number of recent studies in in-vitro fertilization (IVF) patients but the
potential effects of antiphospholipid antibodies on the different
components of the reproductive process and the consideration of whether to
test IVF patients for antiphospholipid antibodies are controversial. The
present study was undertaken to investigate the possible association
between the presence of circulating antiphospholipid antibodies (namely the
lupus anticoagulant and anticardiolipin antibodies), among a series of 21
consecutive IVF patients having a clinical spontaneous abortion after their
first embryo transfer. As a control group (n=42), the nearest IVF cycle
resulting in an ongoing pregnancy before and after each miscarried IVF
cycle (i.e. the closest cycles in temporal relationship to the index cycle)
was used. One patient (4.8%) in the study group and two women (4.8%) among
controls were seropositive for antiphospholipid antibodies. These low and
similar seropositivity rates found in the two groups studied lead us to
conclude that antiphospholipid antibodies testing in IVF patients should be
considered only in those women having repeated failures of
implantation/clinical abortion after embryo transfer but not in an
infertile general population reaching an IVF programme.
相似文献
50.
Huisman JA; Paulussen RJ; Geurts TB; Odink J; Rekers H 《Human reproduction (Oxford, England)》1997,12(1):34-38
The objective was to demonstrate bioequivalence between s.c. and i.m.
administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio
3:1). In two randomized, single-centre, cross-over studies, 18 healthy
volunteers on each formulation were assigned to one of the two
administration sequences. Subjects were given single doses of one of the
above gonadotrophins after endogenous gonadotrophin production had first
been suppressed using high-dose oral contraceptive. Subsequently, rate
(Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone
(FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax
and AUC, analysis of variance (ANOVA) was performed on log-transformed data
and for tmax ANOVA was performed on ranks. Intramuscular and s.c.
injections of Humegon were bioequivalent with respect to the main
pharmacokinetic parameters, being AUC and Cmax of FSH absorption.
Intramuscular and s.c. injections of Normegon were bioequivalent with
respect to the AUC of FSH and not bioequivalent with respect to the Cmax of
FSH. For tmax of FSH as well as for most LH variables of both preparations,
bioequivalence could not be proven due to the high intra- and
interindividual variability and/or concentrations being close to the
detection limit. Thus, the main pharmacokinetic FSH variables after i.m.
and s.c. administration of Humegon and Normegon were bioequivalent.
相似文献