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71.
MRP8 and MRP14 are myeloic related proteins expressed by most circulating and emigrated neutrophils and monocytes. Their composite molecule MRP8/14 (27E10 antigen) was shown to exhibit striking antimicrobial properties. The aim of the present study was to assess the value of MRPs as markers for detection of the different stages of HIV infection (Centres for Disease Control and Prevention, 1993). By employing the ELISA technique we measured serum concentrations of these proteins in samples from 122 HIV patients at the various stages of disease, and the results were compared with those for healthy controls. Serum levels of the heterodimeric molecule 27E10 were significantly increased (P < 0.001) in patients with CDC stages II and III, with the highest levels being in patients with stage III and acute ongoing opportunistic infections. For the single component MRP14, significantly raised levels (P < 0.05) were only found in HIV stage III individuals with acute clinical events. Similar associations were not found for MRP8 alone. Increase was not related to CD4+ cell count. There was a significant correlation between 27E10 antigen serum concentrations and levels of neopterin in patients with HIV stages II and III without acute concurrent illness. Patients being treated with Zidovudine showed no statistically significant variation in levels of 27E10 and its single components MRP8 and MRP14 compared with untreated patients. These findings suggest that elevation of MRP14 levels occurs in HIV+ individuals at later stages post-HIV infection, after the onset of opportunistic infections. 27E10 antigen is concluded to be a potential marker for the different stages of HIV disease.  相似文献   
72.
Recognition of an extensive range of IgE-reactive proteins in cod extract   总被引:1,自引:5,他引:1  
Allergy to fish is one of the most common food allergies. Gad c 1 is the only fish allergen which has been purified and characterized. Other allergens have been detected by Western blot in cod extracts. We have now improved the Western-blot procedure in order to characterize fish IgE-reactive proteins from extracts prepared under different conditions: pre-rigor mortis and postrigor mortis. EDTA addition or not. and DEAE ion-exchange chromatography. Several IgE-reactive protein bands have been identified over a wide molecular-weight range. In particular, the 104- and 130-kDa IgEreactive protein bands were detected. These new bands may correspond to aggregates, as EDTA increased the relative amount of the 60-, 67-, 104-, and 130-kDa IgE-reactive protein bands in Western blot. All these bands were also detected by an antiparvalbumin monoclonal antibody, specific to the first calcium-binding site. The longer period of storage increased the relative amounts of the 41-, 80-, 104-. and 130-kDa IgE-reactive protein bands. The 18-kDa band was detected only in fish stored for several days. In conclusion, we have described IgE-reactive protein bands over a wide molecular-weight range (12–130 kDa) in Western blot of cod extract, and shown that EDTA and storage conditions may influence the relative distribution of IgE-reactive protein bands.  相似文献   
73.
Before completion of polarization, Madin-Darby canine kidney (MDCK) cells showed high infectivity and progeny production of herpes simplex virus type 1 infection. After polarization or formation of tight junctions, the infectivity and virus replication in MDCK cells was restricted significantly. The disruption of tight junctions by depletion of Ca2+ resulted in increasing virus infectivity and productivity. Mechanical disruption of tight junctions by scratching the cell monolayers with injection needle allowed markedly the replication of HSV-I in the cells aligned along the injured area. In polarized MDCK cells the progeny were released preferentially from the apical surface of the cells. These data suggest that because polarized MDCK cells mimic the epithelial cell layers, this cell line is helpful for determining the factors which regulate viral transmission in the human body. © Wiley-Liss, Inc.  相似文献   
74.
Core biopsies of the bone marrow are indispensable in the evaluation of fever of unknown etiology in human immunodeficiency virus-positive patients. We report two patients in whom visceral leishmaniasis was diagnosed based on the typical morphology, staining characteristics, and ultrastructure of the organisms.  相似文献   
75.
Needle puncture and other accidents that occur during surgery and other procedures may lead to viral infections of medical personnel, notably by hepatitis C (HCV) and human immunodeficiency virus (HIV), now that hepatitis B can be prevented by vaccination. A new surgical glove called G-VIR, which contains a disinfecting agent for enveloped viruses, has been developed. Herpes simplex type 1 (HSV) was used as a standard enveloped virus in both in vitro and in vivo tests of the virucidal capacity of the glove. Bovine viral diarrhea virus (BVDV) and feline immunodeficiency virus (FIV) were used as models for HCV and HIV, respectively. For in vitro study, a contaminated needle was passed through a glove and residual virus was titrated; for in vivo studies, animals were stuck with a contaminated needle through a glove. Despite variation in virus enumeration inherent in the puncture technique, statistical evaluation showed that infection was reproducibly and substantially reduced by passage through the virucidal layer. For BVDV, the amount of virus passing through the virucidal glove was reduced in 82% of pairwise comparisons with control gloves that lacked the virucidal agent; when plaque counts were adjusted to a common dilution, the median count for the virucidal glove was on the average reduced >10-fold. In experiments in which the proportion of wells infected with FIV was measured, the ratio of TCID(50) values (control glove to G-VIR) was >15, and probably much higher. For HSV, the amount of virus passing through the virucidal glove was reduced in 81% of comparisons with control gloves; the median of adjusted plaque counts was reduced on the average approximately eightfold or ninefold. In vivo tests with FIV and HSV in cats and mice, respectively, found smaller percentage reductions in infection than the in vitro tests but confirmed the virucidal effect of the gloves.  相似文献   
76.
The epidemiological impact of Acinetobacter baumannii nosocomial infections in a Sicilian intensive care unit (ICU) was investigated to determine the Acinetobacter-specific infection rates, to estimate the preventable proportion of Acinetobacter infections, i.e., those resulting from cross-transmission, and to investigate the molecular epidemiology of antimicrobial resistance in Acinetobacter. The impact of Acinetobacter nosocomial infection in the ICU was determined to be 3.0 new cases per 100 admissions. Site-specific rates confirmed that ICU-acquired pneumonia was the most important infection type. The incidence rate, adjusted by the number of patient-days, was 3.3 infections/1000 patient-days. The estimated preventable proportion of A. baumannii nosocomial infections in the ICU was 66.7%. A class 1 integron, characterised by its gene cassette content, was present in all A. baumannii isolates of four different pulsed-field gel electrophoresis types, and was associated significantly with clones implicated in cross-transmission episodes. Furthermore, the same integron was detected in two genetically distinct isolates responsible for recurrent infection in the same patient, suggesting the occurrence of horizontal gene transfer in vivo. Even in an endemic setting with low infection rates, spread of A. baumannii was caused mainly by infection control shortcomings that require appropriate surveillance and control policies.  相似文献   
77.
Schistosomiasis: an unusual cause of tubal infertility   总被引:3,自引:0,他引:3  
A case report of a Nigerian woman having an unusual cause oftubal infertility is presented. On histological examinationof the Fallopian tube, ova of Schistosoma haematobium enclosingliving miracidia were found in the smooth muscle layer of theFallopian tube and its mesosalpinx. Mechanisms of tubal involvementare analysed. The case indicates the need to consider schisto-somiasisas a possible aetiological factor in patients with tubal infertilitycoming from areas where the disease is endemic.  相似文献   
78.
BACKGROUND: Earlier studies demonstrated a small temperature difference between the sperm storage and fertilization sites within the oviducts of rabbits and pigs. Our aim was to reveal the time dependence of this temperature difference relative to ovulation, and to determine how this difference is generated-by temperature elevation at one of these sites or by temperature decrease at the other site. METHODS: The temperature at the sperm storage site (at the isthmus near the uterotubal junction) and at the fertilization site (the isthmic-ampullary junction) of rabbit oviducts were measured before, during, and after ovulation by two probes, connected to digital thermometers. Rectal temperature was constantly measured and served as a control for body temperature. RESULTS: The temperature difference between the fertilization site and the storage site was 0.8+/-0.2 degrees C before ovulation. This difference increased at ovulation, reaching 1.6+/-0.1 degrees C after ovulation (P<0.03). This increased difference was mainly due to temperature decrease in the sperm storage site. CONCLUSION: The temperature-difference increase within the rabbit oviduct is generated at ovulation by a reduced temperature at the sperm storage site. This temperature gradient may play a role in mammalian reproduction via sperm thermotaxis.  相似文献   
79.
Mixed microbial aetiology of community-acquired pneumonia in children   总被引:2,自引:0,他引:2  
Seven paediatric studies on community-acquired pneumonia with serological methods for both viruses and bacteria have been published, allowing the evaluation of concomitant multiple etiological findings. In these studies, dual viral infection has been present in 0-14%, dual bacterial infection likewise in 0-14%, and mixed viral-bacterial infection in 3-30% of the pneumonia cases. The results confirm former clinical observations that respiratory viruses often pave the way for airway-colonising bacteria. The measured frequency of multiple infections has been dependent on the available test panel, mainly on the tests used for pneumococcal aetiology. Mixed viral-bacterial infections have been especially common in young children under 2 years of age, reflecting the high frequency of respiratory syncytial virus infections and their tendency to induce bacterial co-infections. No microbe-specific viral-bacterial associations have been demonstrated. The clinical implications of mixed viral-bacterial infections, compared with viral infections alone or bacterial infections alone, have so far remained unresolved. Current guidelines recommend antibiotic therapy for all community-acquired pneumonia cases in children.  相似文献   
80.
Mycoplasma hyopneumoniae (Mh) is the primary agent of porcine enzootic pneumonia (PEN), a chronic respiratory disease endemic to pig farms, and characterized histologically by infiltration of mononuclear cells in airways and prominent hyperplasia of the bronchus-associated lymphoid tissue (BALT). To gain further insight into the pathogenesis of PEN, cytokine expression in the lung, with particular attention to the BALT, was examined immunohistochemically in pigs naturally infected with Mh. An increase (P < 0.05) in proinflammatory and immunoregulatory cytokines (especially interleukin [IL]-2, IL-4 and tumour necrosis factor [TNF]-alpha, and to a lesser extent IL-1 [alpha and beta] and IL-6) was detected in the BALT, which showed intense lymphoid hyperplasia. IL-1beta and TNF-alpha were also detected in the bronchoalveolar exudate of infected pigs, and IL-6 and IL-8 were demonstrated in mononuclear cells of the alveolar septa. The results showed that in Mh infection, macrophage and lymphocyte activation results in the expression of a number of cytokines capable of inducing lung lesions and lymphoreticular hyperplasia of the BALT.  相似文献   
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