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Pinocytic rates of macrophages from mice immunized against Toxoplasma gondii and macrophages stimulated to inhibit toxoplasma in vitro. 总被引:2,自引:0,他引:2 下载免费PDF全文
The rate of pinocytosis by macrophages when measured by uptake of horseradish peroxidase was significantly reduced during toxoplasma infection of the cells in vitro when the macrophages were from toxoplasma-immune mice and when control cells were stimulated in vitro to inhibit toxoplasma multiplication. There was, however, no direct correlation between reduced pinocytosis in this model and inhibition or enhancement of toxoplasma multiplication. We conclude that a reduced pinocytic rate is a feature of the unstimulated toxoplasma-immune macrophage, but this change in rate alone does not correlate with the cell's ability to inhibit toxoplasma. In addition, we observed that enhanced pinocytosis as seen in the elicited macrophage was not a requirement for inhibition of toxoplasma multiplication. 相似文献
6.
Neulen J; Raczek S; Pogorzelski M; Grunwald K; Yeo TK; Dvorak HF; Weich HA; Breckwoldt M 《Molecular human reproduction》1998,4(3):203-206
Vascularization is a prominent event during corpus luteum formation,
providing low density lipoproteins for steroid biosynthesis and enabling
transport of secreted steroids. The process of vascularization is
controlled by specific regulators. Vascular endothelial growth factor
(VEGF), otherwise named vascular permeability factor (VPF), induces
endothelial cell proliferation as well as angiogenesis in vivo and
increases capillary permeability. Here we report the expression of VEGF/VPF
mRNA by cultured human luteinized granulosa cells (GC) for at least 10
days. Without HCG VEGF/VPF expression declined after day 4 and by day 10
was reduced to approximately 30% of the value at day 4. However, after
culture in the presence of 1 U/ml human chorionic gonadotrophin (HCG),
expression of VEGF/VPF mRNA by GC was four times greater than control
experiments by day 10, and increased 100% from day 4 to day 10.
Simultaneously, HCG supplementation increased VEGF/VPF secretion by GC.
Medium VEGF/VPF on day 3 was 13 pM without and 11 pM with HCG. Medium
VEGF/VPF on day 10 was 6 pM without HCG and 29 pM with HCG. These results
suggest that vascularization of the corpus luteum is induced by
HCG-mediated effects of VEGF/VPF.
相似文献
7.
Wells GD Plyley M Thomas S Goodman L Duffin J 《European journal of applied physiology》2005,94(5-6):527-540
The efficiency of the respiratory system presents significant limitations on the bodys ability to perform exercise due to the effects of the increased work of breathing, respiratory muscle fatigue, and dyspnoea. Respiratory muscle training is an intervention that may be able to address these limitations, but the impact of respiratory muscle training on exercise performance remains controversial. Therefore, in this study we evaluated the effects of a 12-week (10 sessions week–1) concurrent inspiratory and expiratory muscle training (CRMT) program in 34 adolescent competitive swimmers. The CRMT program consisted of 6 weeks during which the experimental group (E, n=17) performed CRMT and the sham group (S, n=17) performed sham CRMT, followed by 6 weeks when the E and S groups performed CRMT of differing intensities. CRMT training resulted in a significant improvement in forced inspiratory volume in 1 s (FIV1.0) (P=0.050) and forced expiratory volume in 1 s (FEV1.0) (P=0.045) in the E group, which exceeded the S groups results. Significant improvements in pulmonary function, breathing power, and chemoreflex ventilation threshold were observed in both groups, and there was a trend toward an improvement in swimming critical speed after 12 weeks of training (P=0.08). We concluded that although swim training results in attenuation of the ventilatory response to hypercapnia and in improvements in pulmonary function and sustainable breathing power, supplemental respiratory muscle training has no additional effect except on dynamic pulmonary function variables. 相似文献
8.
中国狂犬病毒疫苗株(5aG)糖蛋白基因在痘苗病毒中的表达及免疫效果观察 总被引:1,自引:0,他引:1
将克隆到的中国狂犬病毒疫苗株(5aG)的糖蛋白基因重组到痘苗病毒TK区,并在痘苗病毒P11启动子的控制下,构建了狂犬-痘苗重组病毒(VVaG)。经间接免疫荧光和Western免疫印染证明,重组病毒VVaG能良好地表达狂犬病毒糖蛋白,其分子量约为6600。用VVaG免疫小鼠,7d便可诱生较高的狂犬病毒中和抗体,21d达4169,并能100%保护狂犬病毒本毒株和国际标准攻击毒(CVS)的致死量攻击。 相似文献
9.
Isabel Campos-Varela Oscar Len Ares Villagrasa Ester Márquez-Algaba Juliana Esperalba Cristina Dopazo Ibai Los-Arcos Andrés Antón Lluís Castells 《Transplant international》2021,34(10):1908-1913
Solid organ transplant recipients might be at greater risk for acquisition and mortality because of SARS-CoV-2. There are no data regarding SARS-CoV-2 seroprevalence among liver transplant (LT) recipients, and whether it is different from that of the general population or other immunosuppressed groups. We evaluated the prevalence of IgG SARS-CoV-2 antibodies among LT recipients to estimate the frequency of asymptomatic SARS-CoV-2 infection using serological assays in our outpatient clinic. We conducted a cross-sectional analysis from 10 May to 26 October 2020 of all adult (>18 years) LT recipients that underwent a routine laboratory test for the outpatient clinic follow-up at the Hospital Universitari Vall d’Hebron (Barcelona) in which we included serological testing for SARS-CoV-2. Nine out of 294 LT recipients (3.1%) tested positive for anti-SARS-CoV-2 IgG antibodies. Five of them (55.5%) had suffered clinically symptomatic SARS-CoV-2 infection confirmed by RT-PCR, four (44.4%) had presented compatible symptoms but without microbiological confirmation and only one patient (1/9, 11.1%) tested positive without any previous symptom. SARS-CoV-2 seroprevalence among LT recipients in an area highly affected by the pandemic is lower than in the general population in the same area. These results render the possibility of asymptomatic infection in LT recipients very unlikely. 相似文献
10.
Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection 相似文献