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81.
In the event of smallpox bioterrorism, widespread vaccination may be required. Vaccinia immune globulin (VIG) has been used to treat complications from the smallpox vaccine. While the potency of VIG was defined by its ability to neutralize intracellular mature virus, a second form of vaccinia called the extracellular enveloped virus (EEV) is critical for virus spread in the host. The B5R-protein is one of many EEV-specific proteins. Immunoprecipitation and ELISA revealed that VIG recognizes the B5R-protein. An EEV plaque-reduction assay using a recombinant vaccinia that lacks the majority of the extracellular domain of B5R showed that the ability of VIG to neutralize EEV is principally directed at B5R. In addition, absorbing out the anti-B5R antibody present in VIG through the addition of recombinant B5R protein abrogated VIG's ability to significantly neutralize wild-type EEV. This work demonstrates the prominent role of B5R as a target of EEV-neutralizing activity of human antibodies. 相似文献
82.
83.
Receveur MC Coulaud X Ali R Gasnier O Benoit-Cattin T Pettinelli ME 《Bulletin de la Societe de pathologie exotique (1990)》2003,96(3):238-240
Mayotte is a little French island, located in the Indian ocean, between Madagascar and Mozambic. Officially, the population goes up to 150,000 inhabitants, but in fact, it probably comes up to about 200,000 people, because of a very numerous illegal immigration, especially coming from Anjouan, the nearest Comorian island. Up to now there are no data about HIV in Mayotte. There is only one adult medical unit (except intensive care). All patients detected as seropositive for HIV are sent for treatment in this unit. The only case of systematically proposed HIV serology is pregnancy, and this since 1994. 70% to 80% of women accept it. There are annually 6000 deliveries in Mayotte. When a seropositivity is detected, screening is systematically proposed to other members of the family. Epidemiology does not seem to worsen, even if detection is increasing: 8675 tests done in 1998, 9142 in 1999, 12,085 in 2000. All cases of seropositivity attended to at present time in our unit have been registered and studied, apart from patients who died before this study, and those who did not consult for more than two years. There were 8 HIV positive people who died since 1990 in Mayotte, most of them in 1991, 1992. There was no death in the last years, nor sanitary evacuation, except one. 50 people are registered: 20 males, 30 females. Average age is 34. 39 Comorian people, 10 metropolitans, and one from another origin. Contamination was heterosexual in 43 cases, intravenous drug user in 1 case, homosexual in 2 cases, professional in 1 case, unknown in 3 cases. There are 4 double contamination Ag Hbs/HIV, and 2 HCV/HIV. 39 subjects are at A stage, 5 B, 6 C. The beginning of the epidemic in Mayotte took place probably around 1990, among militaries and prostitutes. Now, transmission keeps going on, in most cases, heterosexual, as it occurs in the nearby Africa. Polygamy, official or officious, has a leading role. Females who were detected during pregnancy have obtained zidovudine, or have been able to pursue previous therapy. Medical care and therapy are free in Mayotte, but sometimes there are delays in supplying medicines or in returning results. Epidemic has not increased up to now; even though screening has. There are very few pediatric cases: only 4 cases were notified in Mayotte until now: one who died very soon, one who has gone to live in Reunion island, and two who are still in Mayotte: one is 12 years old, and another one 5 years old. 相似文献
84.
Isolation rearing has long been suspected to alter hormonal and behavioral responses to stress. Two experiments were conducted to test the hypothesis that isolates are more timid or fearful than socially reared rats when exposed to novel test environments. In both, isolate response to 3 graded stressors was compared to that of socially-reared rats. In the first experiment, animals were handled, shocked or not treated prior to testing to produce three levels of conditioned fear. They were then tested on four paradigms previously shown sensitive to conditioned fear: open field activity, emergence latency, auditory startle, and latency to accept food from the experimenter. In the second experiment, rats were given a 0-, 5- or 20-min forced swim, then sacrificed for analysis of plasma corticosterone and pituitary and hypothalamic beta-endorphin. It was found that isolates showed little evidence of enhanced behavioral timidity, although rearing effects were seen on all 4 behavioral measures. Plasma corticosterone levels increased in a graded fashion over the course of the forced swim, but there was no effect of rearing conditions. While there were no effects of rearing or stress on hypothalamic beta-endorphin, pituitary beta-endorphin content was lower in females than in males, and isolate males had lower pituitary endorphin than social males. In summary, these experiments provide no evidence that isolation rearing produces a primary, global increase in fearfulness, but identify several behavioral and hormonal differences associated with differential housing in rats. 相似文献
85.
Mohammad Sotoudeh Shila Jalali Shunichi Usami John Y-J. Shyy Shu Chien 《Annals of biomedical engineering》1998,26(2):181-189
The objective of this study is to design a new apparatus to allow the control of the magnitude and frequency of dynamic stretch applied uniformly to cells cultured on a silicon elastic membrane. The apparatus is designed to produce equi-biaxial dynamic stretches with area changes ranging from 0% to 55% and frequencies ranging from 0 to 2 Hz. Homogeneous finite strain analysis using triangles of markers was performed to compute the symmetric two-dimensional Lagrangian strain tensor on the membrane. Measurements of strain in both static and dynamic conditions showed that the shear component of the strain tensor (Erc) was near zero, and that there was no significant difference between radial (Err) and circumferential (Ecc) components, indicating the attainment of equi-biaxial strain. Bovine aortic endothelial cells were transiently transfected with a chimeric construct in which the luciferase reporter is driven by TPA-responsive elements (TRE). The transfected cells cultured on the membrane were stretched. The luciferase activity increased significantly only when the cells were stretched by 15% or more in area. Cells in different locations of the membrane showed similar induction of luciferase activities, confirming that strain is uniform and equi-biaxial across the membrane. © 1998 Biomedical Engineering Society.
PAC98: 8780+s, 8745-k, 8722-q 相似文献
86.
The role of COX-2 in angiogenesis and rheumatoid arthritis 总被引:4,自引:0,他引:4
Woods JM Mogollon A Amin MA Martinez RJ Koch AE 《Experimental and molecular pathology》2003,74(3):282-290
Recent evidence suggests that cyclooxygenase (COX)-2 is a mediator of angiogenesis, and COX-2 activity is known to be upregulated in the rheumatoid arthritis (RA) synovium. We examined whether mediation of angiogenesis by COX-2 was occuring in cells of the RA synovium and in microvascular endothelial cells (ECs) that are similar to those found in the RA synovium. We demonstrate that rofecoxib, a selective COX-2 inhibitor, acts directly on human dermal microvascular ECs (HMVECs) to inhibit their chemotactic and tube forming ability. Likewise, pretreatment of HMVECs with rofecoxib significantly inhibited their ability to form tubes induced by conditioned media (CM) of activated RA synovial fibroblasts. When RA synovial fibroblasts were pretreated with rofecoxib for 16 h and then stimulated with interleukin (IL)-1beta, their CM induced significantly less HMVEC tube formation when compared with CM from vehicle-treated RA synovial fibroblasts. ELISAs performed on activated RA fibroblast CM for known proangiogenic factors demonstrated a significant reduction in bFGF, in addition to the expected decrease in PGE(2). Our studies suggest that COX-2-induced angiogenic activity is an active mechanism within diseased synovium and may provide an additional rationale for the use of COX-2 inhibitors in RA. 相似文献
87.
Chen JJ Huang JC Shirtliff M Briscoe E Ali S Cesani F Paar D Cloyd MW 《Journal of leukocyte biology》2002,71(2):271-278
Recent studies have provided evidence that macrophages from Th1-prone mouse strains respond with an M1 profile, and macrophages from Th2-prone mouse strains respond with an M2 profile, characterized by the dominant production of NO or TGF-beta 1, respectively. We have shown that peritoneal macrophages from IL-12p40 gene knockout mice have a bias toward the M2 profile, spontaneously secreting large amounts of TGF-beta 1 and responding to rIFN-gamma with weak NO production. Moreover, IL-12p40KO macrophages are more permissive to Trypanosoma cruzi replication than their wild-type littermate cells. Prolonged incubation with rIL-12 fails to reverse the M2 polarization of IL-12p40KO macrophages. However, TGF-beta 1 is directly implicated in sustaining the M2 profile because its inhibition increases NO release from IL-12p40KO macrophages. IFN-gamma deficiency is apparently not the reason for TGF-beta 1 up-regulation, because rIFN-gamma KO macrophages produce normal amounts of this cytokine. These findings raise the possibility that IL-12 has a central role in driving macrophage polarization, regulating their intrinsic ability to respond against intracellular parasites. 相似文献
88.
This study was designed to analyze cytokine levels in bronchoalveolar lavage (BAL) fluid of patients with pulmonary fibrosis (PF) and was performed at a University hospital. Nineteen veterans had mustard gas-induced PF, and 19 normal veterans were used as a control group. Chest roentgenograms, pulmonary function tests (PFTs), the percentage diffusing capacity of carbon monoxide (D(LCO)), high-resolution CT scans of the chest, and analyses of BAL fluids for five cytokines interleukin-8 (IL-8), IL-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), IL-12, and the growth factors transforming growth factor-beta (TGF-beta), insulin-like growth factor-1 (IGF-1), and epidermal growth factor (EGF) were performed in all cases. A transbronchial lung biopsy was done in all patients. There were significant differences in cytokine (IL-8, IL-1beta, IL-6, TNF-alpha, IL-12) levels of BAL fluid between patients with PF and healthy controls. TGF-beta, EGF, and IGF-1 levels were also significantly increased in patients with PF compared with controls. A significant negative correlation was observed between the percentage of D(LCO) and IL-8 levels in BAL fluid in patients with PF (r = -0.47, p = 0.04). A significant negative correlation was also seen between the percentage of D(LCO) and TGF-beta (r = 0.53, p = 0.02) in these patients. Except for the percentage and the absolute number of the BAL fluid neutrophils (r = 0.70, p = 0.001 and r = -0.62, p = 0.005, respectively), no correlation was found between D(LCO)% and the other BAL cells. Of all measured cytokines and growth factors, only IL-8 and TGF-beta showed a significant correlation with the degree of fibrosis (p = 0.004, p = 0.04). The increased levels of cytokines and growth factors in the BAL fluid suggest the possible causative mechanism in the lung in sulfur mustard gas-induced PF by recruitment of neutrophils and eosinophils into the lung. 相似文献
89.
Real-time quantification in plasma of human telomerase reverse transcriptase (hTERT) mRNA: a simple blood test to monitor disease in cancer patients 总被引:20,自引:0,他引:20
90.
Casonis skin test and indirect haemagglutination test (IHA) are still used in Turkey. The preoperative IHA test or Casonis skin test results of 120 patients with surgically confirmed hydatidosis were retrospectively studied during 1997–2004. At the same period, 306 patients with non-hydatid disease had serologic results for echinococcosis. The sensitivity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 70, 62, and 56%, respectively. Casonis skin test components had higher sensitivity than IHA (P<0.01). The specificity of immediate intradermal reaction, delayed intradermal reaction, and IHA were 87, 85, and 84%, respectively. Cystic lesions in non-hydatid patients were localised commonly in the lungs. The occurrence of hydatid disease for pulmonary, hepatic, and renal cysts was 19, 54, and 5%, respectively. An immediate skin reaction to crude hydatid antigens is more useful than IHA. 相似文献