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71.
Benito N Moreno A Filella X Miró JM González J Pumarola T Valls ME Luna M García F Rañó A Torres A Gatell JM 《Clinical and diagnostic laboratory immunology》2004,11(3):608-614
We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1beta (IL-1beta), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-alpha) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-alpha, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1beta, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-alpha levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5). 相似文献
72.
Rojas OL González AM González R Pérez-Schael I Greenberg HB Franco MA Angel J 《Virology》2003,314(2):671-679
Using an intracellular cytokine assay, we recently showed that the frequencies of rotavirus (RV)-specific CD4(+) and CD8(+) T cells secreting INFgamma, circulating in RV infected and healthy adults, are very low compared to the frequencies of circulating cytomegalovirus (CMV) reactive T cells in comparable individuals. In children with acute RV infection, these T cells were barely or not detectable. In the present study, an ELISPOT assay enabled detection of circulating RV-specific INFgamma-secreting cells in children with RV diarrhea but not in children with non-RV diarrhea without evidence of a previous RV infection. Using microbead-enriched CD4(+) and CD8(+) T cell subsets, IFNgamma-secreting RV-specific CD8(+) but not CD4(+) T cells were detected in recently infected children. Using the same approach, both CD4(+) and CD8(+) RV-specific T cells were detected in healthy adults. Furthermore, stimulation of purified subsets of PBMC that express lymphocyte homing receptors demonstrated that RV-specific INFgamma-secreting CD4(+) T cells from adult volunteers preferentially express the intestinal homing receptor alpha4beta7, but not the peripheral lymph node homing receptor L-selectin. In contrast, CMV-specific INFgamma-secreting CD4(+) T cells preferentially express L-selectin but not alpha4beta7. These results suggest that the expression of homing receptors on virus-specific T cells depends on the organ where these cells were originally stimulated and that their capacity to secrete INFgamma is independent of the expression of these homing receptors. 相似文献
73.
Alvarez JC Díaz C Suárez C Fernández JA González del Rey C Navarro A Tolivia J 《Mechanisms of ageing and development》2000,114(3):149-172
The data concerning the effects of age on the brainstem are scarce and few works are devoted to the human vestibular nuclear complex. The study of the effects of aging in the vestibular nuclei could have clinical interest due to the high prevalence of balance control and gait problems in the elderly. We have used in this work eight human brainstems of different ages sectioned and stained by the formaldehyde-thionin technique. The neuron's profiles were drawn with a camera lucida and Abercrombie's method was used to estimate the total number of neurons. The test of Kolmogorov-Smirnov with the correction of Lilliefors was used to evaluate the fit of our data to a normal distribution and a regression analysis was done to determine if the variation of our data with age was statistically significant. Aging does not affect the volume or length of the vestibular nuclear complex. Our results clearly show that neuronal loss occurs with aging in the descending (DVN), medial (MVN), and lateral (LVN) vestibular nuclei, but not in the superior (SVN). There are changes in the proportions of neurons of different sizes but they are not statistically significant. The neuronal loss could be related with the problems that elderly people have to compensate unilateral vestibular lesions and the alterations of the vestibulospinal reflexes. The preservation of SVN neurons can explain why vestibulo-ocular reflexes are compensated after unilateral vestibular injuries. 相似文献
74.
Angiotensin-(1–7) stimulates water transport in rat inner medullary collecting duct: evidence for involvement of vasopressin V2 receptors 总被引:1,自引:0,他引:1
Magaldi AJ Cesar KR de Araújo M Simões e Silva AC Santos RA 《Pflügers Archiv : European journal of physiology》2003,447(2):223-230
The peptide angiotensin-(1–7) [Ang-(1–7)] is known to enhance water transport in rat inner medullary collecting duct (IMCD). The aim of this study was to determine the mechanism of the Ang-(1–7) effect on osmotic water permeability (P
f). P
f was measured in the normal rat IMCD perfused in vitro in presence of agonists [Ang-(1–7), arginine vasopressin (AVP) and Ang-(3–8)], and antagonists of the angiotensin and the vasopressin cascade. Ang-(1–7), but not Ang-(3–8), increased P
f significantly. The effect of Ang-(1–7) on P
f was abolished by its selective antagonist, A-779, added before or after Ang-(1–7). Prostaglandin E2 and the protein kinase A inhibitor H8 also blocked the Ang-(1–7) effect. Blockade of vasopressin V1 receptors by antagonists did not change the Ang-(1–7) effect, but pre-treatment with a V2 antagonist abolished the effect of Ang-(1–7) on P
f. Similarly, pre-treatment with A-779 inhibited AVPs effect on P
f. Forskolin-stimulated P
f was blocked both by A-779 and by the V2 antagonist. Finally, Ang-(1–7) increased cAMP levels in fresh IMCD cell suspensions whilst the forskolin-stimulated cAMP synthesis was decreased by A-779 and the V2 antagonist. These data provide evidence that Ang-(1–7) interacts via its receptor with the AVP V2 system through a mechanism involving adenylate-cyclase activation. 相似文献
75.
Scientific information regarding plants used in folk medicine in the form of teas and their effect on human health or on genetic material has been the subject of many different types of investigation. The antimutagenic activity of two plants Maytenus ilicifolia and Peltastes peltatus, both rich in compounds of the flavonoid and tannin groups and frequently employed in folk medicine, was studied. Antimutagenicity was determined against known mutagenic substances (4-oxide-1-nitroquinoline, sodium azide, 2-nitrofluorene, aflatoxin B(1), 2-aminofluorene and 2-aminoanthracene), using the Salmonella/microsome assay. Infusions of P.peltatus showed high cytotoxicity and a co-mutagenic effect for induction of base pair substitution mutations with 4-oxide-1-nitroquinoline (-S9 mix). Infusions of M.ilicifolia produced similar effects for frameshift and base pair substitution mutations. With the mutagens 2-nitrofluorene (TA98) and sodium azide (TA100) no significant enhancement effects (co-mutagenic effects) were observed and inhibition of mutagenic activity and cytotoxicity were also diminished. In assays evaluating antimutagenic activity in the presence of metabolic activation utilizing S9 mix, high and significant inhibition of aflatoxin B(1)-, 2-aminofluorene- and 2-aminoanthracene-induced mutagenicity was observed in the presence of the infusions using both TA98 and TA100 and employing doses ranging from 25 to 500 mg/plate. Seventy-five percent of the doses tested exhibited a significant or suggestive decrease in induced mutagenicity with the infusion of M.ilicifolia. With the infusion of P.peltatus significant or suggestive antimutagenic responses were observed with 50% of the doses evaluated. Complexity was clearly noted in the responses observed in the interaction of aqueous extracts of M.ilicifolia and P.peltastes with the genetic material and metabolites generated by the S9 mix played an important role in the protection of DNA. 相似文献
76.
Severe, late-onset graft-versus-host disease in a liver transplant recipient documented by chimerism analysis 总被引:4,自引:0,他引:4
Pollack MS Speeg KV Callander NS Freytes CO Espinoza AA Esterl RM Abrahamian GA Washburn WK Halff GA 《Human immunology》2005,66(1):28-31
A 52-year-old liver transplant recipient presented 8 months after transplantation with oral thrush, then 3 days later with oral ulcers and a diffuse rash, and 5 days later with an acutely reduced white blood cell count, rash, fever, and diarrhea. Bone marrow biopsy revealed severe aplasia. Although graft-versus-host disease (GVHD) was considered, the late onset of these symptoms was felt to render this etiology unlikely because GVHD usually occurs 2 to 6 weeks after transplantation. All potentially myelosuppressive medications were discontinued, and the patient was treated with high doses of hematopoietic growth factors. Because his symptoms continued, chimerism analysis was performed, which indicated that 96% of the peripheral blood mononuclear cells were of liver-donor origin. Ultimately, the patient underwent an allogeneic peripheral blood hematopoietic progenitor cell transplant from a human leukocyte antigen-identical brother, but he died 5 days after transplantation of overwhelming Candida kruseii infection. To our knowledge, this is the first chimerism-analysis-documented case of severe acute GVHD presenting so late after liver transplantation. It is of note that the patient had no known risks for GVHD in that he was relatively young and shared only one major human leukocyte antigen with his donor. Consideration should be given to GVHD as a cause of bone marrow aplasia at any time after organ transplantation. Storage of cell pellets from all transplant recipients and donors is highly recommended to facilitate the diagnostic evaluation. 相似文献
77.
Quintero A Martínez D Alarcón De Noya B Costagliola A Urbina L González N Liprandi F Castro De Guerra D Pujol FH 《Archives of virology》2002,147(9):1829-1836
Summary. Hepatitis B virus (HBV) infection among Venezuelan populations of African origin was analyzed. These populations exhibited
lower HBV prevalence than the one found in the African continent. Sequence analysis of 6 isolates showed that 3 belonged to
genotype F, while the 3 others were HBV genotype A. HBV genotype A was more common in the Afro-Venezuelan groups than in the
general Venezuelan population. This might reflect the introduction of genotype A during the slavery period. The absence of
the African genotype E among these isolates supports the hypothesis of a recent origin for this HBV genotype. HBV genotype
F has already been introduced to these relatively isolated communities.
Received February 18, 2002; accepted March 8, 2002 Published online July 22, 2002 相似文献
78.
Cesar Arenas-Mena 《Developmental dynamics》2007,236(6):1611-1622
Two major variants of the stereotypic spiral cleavage correlate with distinct developmental modes in polychaetes. Indirect development through a feeding trochophore larva correlates with development from four equal-sized blastomeres, whereas direct development correlates with unequal cleavage characterized by a large dorsal blastomere precursor maternally predetermined. The equal-size spiral cleavage of the indirectly developing serpulid Hydroides elegans has been reconstructed from serial sections of nuclei-stained embryos. The order of cell divisions has been determined from the 2-cell stage to the 80-cell stage, when gastrulation cell movements start to overlap with late spiral-cleavage divisions. In contrast to related species, the third cleavage in Hydroides elegans is invariably sinistral. The four quadrants remain indistinct until the 60-cell stage, when the small 2d22 and large 2d21 cells are generated. The developmental significance of the invariant spiral cleavage relates to the spatial distribution of gene functions that it partitions and their relation to blastomere fate commitments. The conservation and divergence of the cleavage pattern among spiralians is well suited to study the developmental control of the cell-cleavage machinery and its evolution. 相似文献
79.
Frantiek Moravec Isaure de Buron Tiffany G. Baker David González-Solís 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(4):382-391
Three gonad-infecting species of Philometra Costa, 1845 were, for the first time, recorded from perciform fishes from estuarine and marine waters in South Carolina and
Georgia, USA: Philometra charlestonensis sp. nov. from the scamp Mycteroperca phenax (Jordan et Swain) (Serranidae), P. saltatrix Ramachandran, 1973 from the bluefish Pomatomus saltatrix (Linnaeus) (Pomatomidae), and Philometra sp. from the Atlantic croaker Micropogonias undulatus (Linnaeus) (Sciaenidae). The new species is characterized mainly by males (body length 2.65–3.14 mm) with equally long, needle-like
spicules (length 132–141 μm) and the gubernaculum (81–93 μm) bearing dorsal transverse lamella-like structures on its distal
portion, the body length of gravid females (168–247 mm), the presence of a well-developed anterior bulbous inflation on the
female oesophagus, and by the length of the first-stage larvae (544–597 μm). A key to gonad-infecting species of Philometra parasitizing marine and brackish-water fishes is provided. 相似文献
80.
Prokhorov EF González-Hernández J Vorobiev YV Morales-Sánchez E Prokhorova TE Zaldivar Lelo de Larrea G 《Medical & biological engineering & computing》2000,38(5):507-511
The aim is to compare the mean values of the in vivo electrical characteristics of bioiogical active points (BAPs) with those
of the surrounding human skin. The impedance measurements at BAPs and on the surrounding skin are carried out in vivo on ten
young, healthy people. The results of the measurements show that the BAP resistance RP is smaller, and the capacitance CP is higher, than the corresponding values for skin, RS and CS, respectively, these differences are larger at low frequencies (at f=3 Hz, RS/RP=3.19 and CP/CS=3.2). The mean values of the impedance measurements at the BAPs are different from those measured on the skin. The dependence
of RP and CP on the pressing force, in the range of about 1–5 N, for the BAPs, has a smaller slope than that observed for the surrounding
skin. An equivalent circuit for the BAPs is proposed that describes sufficiently well the experimental results obtained. These
results show that the large dispersion in the observed impedance characteristics of the human body measurements in different
body regions can be related to the influence of the BAPs present under the electrodes. 相似文献