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981.
Modiano D Luoni G Petrarca V Sodiomon Sirima B De Luca M Simporé J Coluzzi M Bodmer JG Modiano G 《Tissue antigens》2001,57(2):128-137
Fulani of Burkina Faso (West Africa) are a particularly interesting ethnic group because of their lower susceptibility to Plasmodium falciparum malaria as compared to sympatric populations, Mossi and Rimaibé. Moreover, the occurrence of a Caucasoid component in their genetic make-up has been suggested on the basis of their physical traits and cultural traditions even though this view was not supported by genetic studies. A total of 149 unrelated subjects (53 Mossi, 47 Rimaibé and 49 Fulani) have been typed for 97 HLA class I alleles with the amplification refractory mutation system/polymerase chain reaction (ARMS/PCR) technique. Mossi and Rimaibé data were pooled since none of the 42 statistically testable alleles exhibited a significant heterogeneity. These pooled gene frequencies were found to be very different from those of Fulani: a certain (P<0.001) or a likely (0.001
相似文献
982.
Correlation of preS antigens and clinical status during chronic hepatitis B virus infection 总被引:1,自引:0,他引:1
G. Taliani M. Rapicetta D. Francisci J. Xiang B. Sarrecchia C. De Bac G. Stagni 《Medical microbiology and immunology》1991,180(5):239-248
The serum kinetics of preS1 and preS2 antigens has been evaluated in 38 serial samples from eight patients with chronic active (CAH) or chronic persistent (CPH) hepatitis, followed for 2–7 years (mean 4.4 years) in whom liver biopsy was performed at intervals, and in 46 samples from ten asymptomatic HBsAg carriers followed for 4–5 years (mean 4.6 years). Four patterns of preS behaviour have been observed: (1) persistently positive preS1 and preS2; (2) disappearance of preS2; (3) disappearance of both preS1 and preS2; and (4) persistently negative preS1 and preS2. Pattern 4 has been observed exclusively among healthy carriers, while seven out of eight chronic patients exhibited either pattern 1 or 2. Among the chronic patients, preS2 disappearance was accompanied or followed by alanine aminotransferase (ALT) normalization. The correlation of preS antigens with conventional viral replication markers showed that 100% of hepatitis B virus (HBV)-DNA-positive and 86.6% of HBeAg-positive sera were preS1/preS2 positive, while 61% of HBV-DNA-negative and 64% of HBeAg-negative sera were preS1/preS2 negative. Our data suggest that continuous monitoring of preS antigens in follow-up sera will allow for an improved prognostic evaluation of chronic HBV infection. 相似文献
983.
Capodicasa E Russano AM Ciurnella E De Bellis F Rossi R Scuteri A Biondi R 《Immunopharmacology and immunotoxicology》2000,22(4):671-683
Plasma levels of human polymorphonuclear elastase (PMN-E) are considered a marker of granulocyte activation and can potentially complement the peripheral neutrophil count in laboratory and pathophysiological settings. Neutrophilic leukocytosis is a well known effect of lithium therapy, but there is no information about the concomitant behaviour of PMN-E in these patients. The aim of this study was to evaluate both polymorphonuclear leukocyte count and plasma PMN-E levels in depression patients undergoing chronic lithium therapy. Absolute and differential leukocyte count in venous peripheral blood was determined by an automated method, and PMN-E evaluated by enzyme immunoassay. 39 patients (11 males, 28 females; mean age 43. +/- 6.02) with depression disorders were studied, during lithium carbonate therapy. Neutrophilia (neutrophil count > 7.500x10(9) cells per liter) was found in 7 (18%) patients and an increase in plasma PMN-E levels (PMN-E > 56 microg per liter ) in 6 (15%). No correlations were found between neutrophil count, plasma concentration of PMN-E, plasma level of lithium and duration of therapy. The results show that in these patients, not only the PMN count but also elastase levels can exceed the normal range. The absence of correlation between these two parameters suggests that the state of PMN activation is not linked to their number in peripheral blood. 相似文献
984.
K Tintelnot G S De Hoog E Antweiler H Losert M Seibold M A Brandt A H G Gerrits Van Den Ende M C Fisher 《Medical mycology》2007,45(5):385-393
The ribosomal Internal Transcribed Spacer (ITS) regions of the two recognized species of Coccidioides were studied using a reference set of strains that had been previously identified with species defining microsatellite polymorphisms. Unambiguous identification of the two species proved to be possible by amplifying and sequencing the ITS region. PCR-reactions are sensitive to amplification conditions requiring their careful optimization. Stable amplification and sequencing was achieved with primers ITS3 and 4, enabling species diagnosis. Alternatively, Restriction Fragment Length Polymorphism (RFLP) of the entire ITS region using an annealing temperature of 52 degrees C with the restriction enzymes BsrI and XcmI can also distinguish the species. Three strains typifying the species, Glenospora meteuropaea, G. metamericana and Geotrichum louisianoideum, were analyzed and found to be conspecific with C. posadasii. Although these species have nomenclatural priority over C. posadasii, the latter will be proposed for conservation as it has been included in the US select agent list. In addition, Coccidioides immitis is neotypified in this report. Results of antifungal susceptibility testing did not reveal differences between the two species. 相似文献
985.
The Yin-Yang of tumor-associated macrophages in neoplastic progression and immune surveillance 总被引:5,自引:1,他引:5
Paola Allavena Antonio Sica Cecilia Garlanda Alberto Mantovani 《Immunological reviews》2008,222(1):155-161
Summary: An intrinsic (oncogene-driven) pathway and an extrinsic (microenvironment-driven) pathway connect inflammatory reactions and cancer. M2-polarized tumor-associated macrophages and the related myeloid-derived suppressor cells are key prototypic components of smoldering inflammation driving neoplastic progression. However, mononuclear phagocytes can exert anti-tumor activity by killing tumor cells and eliciting tissue disruptive reactions (M1), a likely scenario in the early phases of carcinogenesis of immunogenic tumors and following therapeutic intervention. Shifting the macrophage balance represents a viable therapeutic target. Herein, the 'macrophage balance' is discussed in the context of the apparent paradox of tumor promotion by innate immunity-driven inflammation and the seemingly opposed tumor surveillance by adaptive immune responses. 相似文献
986.
Trifiletti A Lasco A Scamardi R Pizzoleo MA Gaudio A La Rocca R Morini E Frisina N 《Pathophysiology of haemostasis and thrombosis》2003,33(2):84-87
This study assessed hemostatic effects of an HMC-CoA reductase inhibitor, atorvastatin, on different parameters in 32 hypercholesterolemic patients of both sexes. In the patients and in 25 control subjects, plasma levels of tissue-type plasminogen activator, plasminogen activator inhibitor (PAI-1), D-dimer, prothrombin fragment 1 + 2 (F1 + 2), total cholesterol, triglycerides and fibrinogen had been measured. All these parameters were evaluated in patients after 6 and 12 months of treatment with atorvastatin at a dosage of 20 mg/day. This treatment significantly lowered the total cholesterol level in all patients. Moreover, after 6 months of atorvastatin treatment, PAI-1 and F1 + 2, which were both increased at baseline, were significantly reduced. This reduction continued after 12 months. The present results show that a reduction of hemostatic abnormalities, which exist in hypercholesterolemia, may be another important effect of the atorvastatin therapy. 相似文献
987.
F Roch-Ramel F Diezi-Chomety D De Rougemont M Tellier J Widmer G Peters 《The American journal of physiology》1976,230(3):768-776
Free-flow micropuncture experiments were done in rats of three strains infused with small amounts of urate [plasma urate (P urate) = 95 +/- 8 muM]. Urate concentrations in tubular fluid were measured by an accurate chemical fluorometric ultramicromethod. In fluid from surface glomeruli, the glomerular fluid-to-plasma urate ratio [GF/P) urate] was 0.99 +/- 0.03 (n=11), i.e., lower than expected for total ultrafiltrability of plasma urate. Along proximal convolutions, net reabsorption of 55% of filtered urate was demonstrated. Small amounts of urate may have been reabsorbed between late proximal and early distal sites. Net transepithelial movements of urate did not occur in distal tubules or collecting ducts. In microperfusion experiments on proximal tubules, both a reabsorptive flow of urate (loss of perfused [2-14C]urate) and a secretory flow (entrance of cold urate into perfusate) of the same order of magnitude were demonstrated. Neither flow was influenced by simultaneous water movements. Microperfusion of Henle's loops indicated a significant but very small net reabsorption. 相似文献
988.
989.
Urbanelli L Fortugno P Bartoli F Nuzzo M De Tomassi A Felici F Monaci P 《Journal of immunological methods》2000,236(1-2):167-176
We have previously screened a phage-displayed random peptide library using sera from patients and identified ligands binding to antibodies specifically associated with the hepatitis C virus infection. The ability of these peptides to detect HCV-specific antibodies was improved through an in vitro procedure which mimics the natural process of antibody affinity maturation operating in secondary immune response. Libraries were generated by mutating the sequence of the original peptide through a protocol that efficiently introduced substitution, insertion and deletion mutations on a single or population of clones. Screening these libraries isolated mutants that displayed increased specific reactivity with a broader range of sera from HCV-infected patients. Several variants of the original peptide were identified which discriminate between the various components of the specific polyclonal response. This methodology to select artificial ligands from RPL using sera and to enhance their diagnostic properties by affinity maturation makes the development of a diagnostic assay to detect disease-associated antibodies feasible, without requiring the natural antigen. 相似文献
990.
Multiple islet cell tumors with predominance of glucagon-producing cells and ulcer disease 总被引:1,自引:0,他引:1
C Bordi O De Vita F P Pilato G Carfagna T D'Adda G Missale A Peracchia 《American journal of clinical pathology》1987,88(2):153-161
Two cases of multiple islet cell tumors mostly composed of glucagon-producing cells and associated with severe ulcer disease are presented. Multiple endocrine neoplasia type I (MEN-I) was present in both patients, although symptomatically latent in case 2. Immunohistochemistry showed that glucagon (A) cells were a major cell population (i.e., accounting for at least 30% of the tumor cell population) in 24 of 43 tumors (either macroadenomas or microadenomas) studied in case 1 and in 12 of 17 tumors studied in case 2. A major pancreatic polypeptide (PP) cell population was found in 12 and 7 tumors of case 1 and 2, respectively. In contrast, insulin (B) and somatostatin (D) cells were scarce in most adenomas. Gastrin-producing cells were not identified in any tumors, despite the use of different antigastrin antisera. Extrapancreatic or residual gastrinomas were not found at postmortem examination in case 1 or on appropriate surgical inspection done 24 years after the onset of the ulcer disease in patient 2. On the basis of these and of 17 additional cases collected in the literature, it is concluded that multiple A-cell tumors of the pancreas are an expression of the MEN-I and are mostly associated with ulcer disease and/or with hypergastrinemia of frequent uncertain origin. The mechanisms regulating the nonrandom phenotypic hormonal differentiation of these genetically determined tumors remain unknown. 相似文献