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71.
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
72.
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
73.
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
74.
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
75.
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
76.
77.
Alberto Utrero-Rico Javier Ruiz-Hornillos Cecilia González-Cuadrado Claudia Geraldine Rita Berta Almoguera Pablo Minguez Antonio Herrero-González Mario Fernández-Ruiz Octavio Carretero Juan Carlos Taracido-Fernández Rosario López-Rodriguez Marta Corton José María Aguado Luisa María Villar Carmen Ayuso-García Estela Paz-Artal Rocio Laguna-Goya 《The Journal of allergy and clinical immunology》2021,147(5):1652-1661.e1
78.
C. Castro R. Martín T. García E. Rodríguez I. González B. Sanz 《Food and Agricultural Immunology》1992,4(1):11-18
An indirect enzyme‐linked immunosorbent assay (ELISA) has been developed for the specific detection of cow's milk (1–25%) in goat's milk. The test uses polyclonal antibodies raised in rabbits against bovine whey proteins (BWP). The anti‐BWP antibodies were recovered from the crude antiserum by immunoadsorption and elution from a column containing immobilized BWP. The anti‐BWP antibodies were biotinylated and rendered cow's milk specific by mixing them with lyophilized ovine and caprine whey proteins. Streptavidin‐peroxidase was used to detect the biotinylated anti‐BWP antibodies bound to bovine milk proteins immobilized on 96‐well plates. The colour developed by the subsequent enzymic conversion of the substrate gave clear absorbance differences when assaying mixtures of goat's milk containing variable amounts of cow's milk. 相似文献
79.
Cristina Benito Eloína González-Mancebo M Dolores Alonso Díaz de Durana Rosa M Tolón Montserrat Fernández-Rivas 《Annals of allergy, asthma & immunology》2007,98(6):580-584
BACKGROUND: Coconut (Cocos nucifera) is a monocotyledonous plant of the Arecaceae family. Allergy to coconut is infrequent, with only 5 cases reported so far in the medical literature. OBJECTIVE: To identify coconut allergens in 2 patients allergic to this food. METHODS: We describe 2 patients allergic to coconut: an adult pollen-allergic patient monosensitized to coconut who presented with severe oropharyngeal symptoms and a child with a previous allergy to walnut, not allergic to pollen, who developed anaphylaxis on coconut ingestion. Both patients had positive skin prick test results and serum specific IgE (CAP) to coconut. IgE sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting was performed to identify the allergens involved, and a strong IgE binding band detected in both patients was further analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). Stability to pepsin digestion of the coconut extract and its cross-reactivity with tree nuts were studied. RESULTS: An immunoblot showed an almost identical profile of IgE binding proteins in the coconut extract in both patients who reacted strongly to a band of approximately 29 kDa. The peptide analysis by MALDI-TOF MS of this band obtained the sequence GHGKREDPEKR. The protein with the highest correlation with this peptide was found to be a 7S globulin from Elaeis guineensis, another oil palm species also belonging to the Arecaceae family. The 29-kDa band was digested by pepsin in less than 1 minute. Cross-reactivity among coconut, walnut, and hazelnut was demonstrated by CAP inhibition in patient 2. CONCLUSION: We have identified a 7S storage protein as a novel coconut allergen. 相似文献
80.
Krustrup P Söderlund K Mohr M González-Alonso J Bangsbo J 《Pflügers Archiv : European journal of physiology》2004,449(1):56-65
To investigate recruitment of slow-twitch (ST) and fast-twitch (FT) muscle fibres, as well as the involvement of the various quadriceps femoris muscle portions during repeated, intense, one-legged knee-extensor exercise, 12 healthy male subjects performed two 3-min exercise bouts at ~110% maximum thigh O2 consumption (EX1 and EX2) separated by 6 min rest. Single-fibre metabolites were determined in successive muscle biopsies obtained from the vastus lateralis muscle (n=6) and intra-muscular temperatures were continuously measured at six quadriceps muscle sites (n=6). Creatine phosphate (CP) had decreased (P<0.05) by 27, 73 and 88% in ST fibres and 25, 71 and 89% in FT fibres after 15 and 180 s of EX1 and after 180 s of EX2, respectively. CP was below resting mean–1 SD in 15, 46, 84 and 100% of the ST fibres and 9, 48, 85 and 100% of the FT fibres at rest, after 15 and 180 s of EX1 and after 180 s of EX2, respectively. A significant muscle temperature increase (Tm) occurred within 2–4 s at all quadriceps muscle sites. Tm varied less than 10% between sites during EX1, but was 23% higher (P<0.05) in the vastus lateralis than in the rectus femoris muscle during EX2. Tm in the vastus lateralis was 101 and 109% of the mean quadriceps value during EX1 and EX2, respectively. We conclude that both fibre types and all quadriceps muscle portions are recruited at the onset of intense knee-extensor exercise, that essentially all quadriceps muscle fibres are activated during repeated intense exercise and that metabolic measurements in the vastus lateralis muscle provide a good indication of the whole-quadriceps muscle metabolism during repeated, intense, one-legged knee-extensor exercise. 相似文献