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11.
Tania C. Araújo-Jorge Maria de Nazareth Leal de Meirelles Lourdes Isaac 《Parasitology research》1990,76(7):545-552
We report that alpha-2-macroglobulin (A2M), the physiologically important plasma protease inhibitor and suspected immunomodulator, alters the functional ability of murine resident peritoneal macrophages (RM) to ingest and kill the infective trypomastigote stage ofTrypanosoma cruzi, the aetiological agent of Chagas' disease. Treatment of RM with 500 g/ml A2M for 30 min enhanced the uptake of trypomastigotes, epimastigotes, and amastigotes by 125%, 46%, and 300%, respectively. The same treatment also increased the phagocytosis of sheep erythrocytes opsonized with complement and IgG as well as of galactosylated asialoerythrocytes. After 60–90 min parasite-cell interaction, epi-and amastigotes were killed by the RM, whereas the infection with trypomastigotes was controlled only after 24 h. Other protease inhibitors, bovine serum albumin, and LPS showed no such effect. The production of hydrogen peroxide was not affected by A2M treatment, but the ultrastructural aspects showed trypomastigote damage and enhancement of macrophage membrane ruffling, indicative of macrophage activation. These results suggest that A2M has the ability to modulate, at least functionally, certain receptor-mediated endocytic pathways that, in concert with an activation of possibly oxygen-independent microbicidal mechanisms, could contribute to resistance against the parasite.Abbreviations A2M
alpha-2-macroglobulin
- F-A2M
fast A2M
- S-A2M
slow A2M
- RM
resident macrophages
- BT
bloodstream trypomastigotes
- EPI
epimastigotes
- AMA
amastigotes
- DMEM
Dulbecco's Modified Eagle Medium
- PBS
phosphate-buffered saline
- BSA
bovine serum albumin
- LPS
bacto lipopolysaccharide
- STI
sovoean trypsin inhibitor
- PPA
pepstatin A
- LPT
leupeptin
- PNT
1, 10-phenanthroline
- TLCK
N--tosy-L-lysine-chloromethylketone
- E
sheep erythrocyte
- aE
asialoerythrocyte
- Gal R
receptors for galactosylated particles 相似文献
12.
BACKGROUND: Rates of remission and relapse were studied over more than 2 years in a sample of Spanish outpatients with DSM-III-R criteria of unipolar major depressive episodes. METHODS: Patients were treated following standardised pharmacological protocols at our centre. In the first visit, the structured clinical interview for DSM-III-R (SCID) was used. The following visits were held monthly. Phases of evolution were recorded using the Hamilton Depression Rating Scale (HDRS), applying the Frank criteria. RESULTS: A significantly greater proportion of relapse was observed in the partial remission group compared to the complete remission one. The rate of relapses for patients in complete remission was 15.18%, while for patients in partial remission was 67.61%. Partial remission was significantly associated with relapses. LIMITATIONS: The short duration of the study and the decreasing sample size during the follow-up. CONCLUSIONS: Partial remission after a depressive episode seems to be strongly associated with relapses. Moreover, this clinical factor could by itself fully predict short-term relapses. CLINICAL RELEVANCE: The study shows the importance of reaching complete remission to decrease the rate of short-term relapses. 相似文献
13.
Villalba-Caloca J García-García Mde L Sifuentes-Osornio J Sada-Díaz E Salazar-Lezama MA 《Gaceta médica de México》2003,139(5):471-492
Tuberculosis is a public health problem. If the current trends continue, is expected to arrive to 10.2 million of new cases in 2005. There are three studies accomplished in 1995 in Mexican patients. The results show important difficulty in the application and the follow-up of the program of control of the tuberculosis, what has caused accumulation of chronic cases, moderate rate of primary resistance and alarming levels of primary and secondary multiresistance (23%). Mechanism of protective immunity against mycobacterium tuberculosis (MTB) in humans have not been clarified. Different subpopulations of lymphocytes CD4, CD8 and other populations as well as macrophages, and monocytes, have an important role. In industrialized countries, the managing of the MDRTB is based on the use of individualized treatments with second line drugs according to susceptibility test, however the foregoing has not been possible to apply it middle or low income countries. WHO has launches the initiative "DOTS plus" that consist in the administration of a standarized regimen on the basis of epidemiology of resistance in the country or region. 相似文献
14.
Zamora L Espinet B Salido M Florensa L Woessner S Pedro C Serrtano S Solé F 《Cancer Genetics and Cytogenetics》2002,134(2):165-167
We report a 89-year-old female diagnosed with chronic myelomonocytic leukemia (CMMoL) presenting with a monosomy 15. To our knowledge, this is the second reported case of CMMoL with monosomy 15. On the other hand, monosomy 15 in complex karyotypes is a frequent chromosome aberration in myelodysplastic syndromes, particularly in refractory anemia with excess of blasts. 相似文献
15.
Cachofeiro V Fortepiani LA Navarro-Cid J Lahera V García-Estañ J 《Antioxidants & redox signaling》2002,4(6):885-891
The effects of the chronic inhibition of nitric oxide (NO) on renal hemodynamics and tubular function were studied in rats treated for 8 weeks with the NO synthesis inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME; 40 mg/kg/day). In addition, the effect of L-NAME administration on vasoactive systems (renin-angiotensin system, aldosterone, catecholamines, endothelin, and thromboxane A(2)) was evaluated. Chronic inhibition of NO significantly elevated blood pressure, reduced glomerular filtration rate and renal blood flow, blunted the pressure-diuresis-natriuresis response, and increased protein urine excretion. All these changes were associated with blunted nitrite production in response to acetylcholine in glomeruli. No changes were observed in the plasma levels of either renin activity, aldosterone, or endothelin in L-NAME-treated rats. Similarly, no differences were observed in the urinary excretion of thromboxane B(2) between both group of animals. By contrast, plasma concentrations of both epinephrine and norepinephrine were elevated in rats treated with L-NAME. In summary, the results show that chronic blockade of NO produced not only alterations in renal function, but also renal damage, suggesting an important renoprotective role of NO. An activation of sympathoadrenal system could participate in these renal alterations. 相似文献
16.
Camargo Carlos Henrique de Souza da Cunha Maria de Lourdes Ribeiro Caramori Jacqueline Costa Teixeira Mondelli Alessandro Lia Montelli Augusto Cezar Barretti Pasqual 《International urology and nephrology》2021,53(2):381-381
International Urology and Nephrology - In the original publication, article title was incorrectly published. 相似文献
17.
18.
Carlos Solano Lourdes Vázquez Estela Giménez Rafael de la Cámara Eliseo Albert Montserrat Rovira Ildefonso Espigado Carmen M. Calvo Javier López-Jiménez María Suárez-Lledó Anabella Chinea Albert Esquirol Ariadna Pérez Aránzazu Bermúdez Raquel Saldaña Inmaculada Heras Ana J. González-Huerta Tamara Torrado Guiomar Bautista Montserrat Batlle Santiago Jiménez Carlos Vallejo Pere Barba María Á. Cuesta José L. Piñana David Navarro 《American journal of transplantation》2021,21(1):258-271
The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research. 相似文献
19.
Espinet B Solé F Pedro C Garcia M Bellosillo B Salido M Florensa L Camacho FI Baró T Lloreta J Serrano S 《Human pathology》2005,36(11):1232-1237
Mantle cell lymphoma (MCL) is a B-cell neoplasm with a relatively aggressive clinical course. There is a very small subgroup of patients who present with atypical lymphocytes in peripheral blood, with or without lymphocytosis, lymphadenopathy, or splenomegaly, and with an indolent clinical course. They frequently show mutated IgV(H) genes and CD5 negativity. We report an asymptomatic elderly patient who presented with a single submandibular lymphadenopathy. The biopsy showed immunophenotype and t(11;14)(q13;q32) consistent with MCL. The abnormal lymphoid population was also detected in peripheral blood and bone marrow. The patient has remained asymptomatic for 5 years without receiving any therapy. It is uncertain whether these cases represent an early-stage event in the development or an indolent form of MCL. The existence of such asymptomatic patients with an indolent clinical course should induce a strict clinical judgment in terms of therapeutic decisions. 相似文献
20.
Mercury and selenium interaction: A review 总被引:10,自引:1,他引:9
Ma. Lourdes A. Cuvin-Aralar Robert W. Furness 《Ecotoxicology and environmental safety》1991,21(3):348-364
This paper reviews studies on mercury and selenium interaction. It includes the effects of selenium on mercury toxicity on the organism, organ/tissue, and subcellular levels. The paper also touches on possible mechanisms for the "protective action" of selenium against mercury toxicity and deals briefly with the synergism between the two elements. 相似文献