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51.
Camara AA Silva JM Ferriani VP Tobias KR Macedo IS Padovani MA Harsi CM Cardoso MR Chapman MD Arruda E Platts-Mills TA Arruda LK 《The Journal of allergy and clinical immunology》2004,113(3):551-557
BACKGROUND: Risk factors for acute wheezing among children in subtropical areas are largely unknown. OBJECTIVE: To investigate the role of viral infections, allergen sensitization, and exposure to indoor allergens as risk factors for acute wheezing in children 0 to 12 years old. METHODS: One hundred thirty-two children 0 to 12 years of age who sought emergency department care for wheezing and 65 children with no history of wheezing were enrolled in this case-control study. Detection of respiratory syncytial virus antigen, rhinovirus and coronavirus RNA, adenovirus, influenza, and parainfluenza antigens was performed in nasal washes. Total IgE and specific IgE to mites, cockroach, cat, and dog were measured with the CAP system. Major allergens from mites, cockroach, cat, and dog were quantified in dust samples by ELISA. Univariate and multivariate analyses were performed by logistic regression. RESULTS: In children under 2 years of age, infection with respiratory viruses and family history of allergy were independently associated with wheezing (odds ratio, 15.5 and 4.2; P = .0001 and P = .008, respectively). Among children 2 to 12 years old, sensitization to inhalant allergens was the major risk factor for wheezing (odds ratio, 2.7; P = .03). High-level allergen exposure, exposure to tobacco smoke, and lack of breast-feeding showed no association with wheezing. CONCLUSIONS: Some risk factors for wheezing previously identified in temperate climates were present in a subtropical area, including respiratory syncytial virus infection in infants and allergy in children older than 2 years. Rhinovirus was not associated with wheezing and did not appear to be a trigger for asthma exacerbations. 相似文献
52.
Kummrow M Meli ML Haessig M Goenczi E Poland A Pedersen NC Hofmann-Lehmann R Lutz H 《Clinical and diagnostic laboratory immunology》2005,12(10):1209-1215
To determine the prevalence of antibodies to feline coronavirus (FCoV) serotypes 1 and 2 in Switzerland and their association with different disease manifestations, a serological study based on immunofluorescence tests was conducted with Swiss field cats using transmissible gastroenteritis virus (TGEV), FCoV type 1 and FCoV type 2 as antigens. A total of 639 serum samples collected in the context of different studies from naturally infected cats were tested. The current study revealed that, with an apparent prevalence of 83%, FCoV serotype 1 is the most prevalent serotype in Switzerland. FCoV type 1 viruses induced higher antibody titers than FCoV type 2, and were more frequently associated with clinical signs and/or feline infectious peritonitis. The antibody development in seven cats experimentally infected with FCoV type 1 revealed that, with progressing duration of infection, antibodies to FCoV type 1 significantly increased over those to FCoV type 2. There was a significant relationship between antibody titers against TGEV, FCoV 1, and FCoV 2 and TGEV antigen detected the highest proportion of seropositive cats. We conclude that a vaccine against FCoV should be based on FCoV type 1-related antigens and that for serodiagnosis of FCoV infection TGEV should be used to attain the highest diagnostic efficiency. When serology is used in addition to clinical signs, hematology, and clinical chemistry results as an aid to diagnose clinical FIP, TGEV shows a diagnostic efficiency equal to that of a FCoV antigen. 相似文献
53.
Barbara Riond Marina L. Meli Ueli Braun Peter Deplazes Kaspar Joerger Rudolf Thoma Hans Lutz Regina Hofmann-Lehmann 《Comparative clinical pathology》2008,17(3):171-177
An outbreak of a fatal haemolytic anaemia in a dairy herd of cattle in Switzerland was shown to be associated with infections
with five vector-borne pathogens, namely Anaplasma marginale, A. phagocytophilum, Babesia bigemina, a Theileria spp belonging to the buffeli/sergenti/orientalis complex and haemotrophic Mycoplasma spp. The latter three had not been documented before this outbreak in Switzerland. To characterise the haematological and blood
chemical changes in these unique cows, packed cell volume was determined in all 286 blood samples, blood smears, and complete
haematology were performed from 285 and 173 blood samples, respectively, and biochemical parameters were assayed in 105 serum
samples. Regenerative anaemia was the key sign of illness. Red blood cells of anaemic cattle were hypochromic and macrocytic.
Anaemic animals had reduced platelet cell counts and increased total white cell counts. In addition, increased serum bilirubin,
blood aspartate aminotransferase, gamma glutamyltransferase, glutamic dehydrogenase and blood urea nitrogen and decreased
magnesium, calcium and albumin levels were found in anaemic cattle when compared to animals with normal packed cell volume.
Most changes could not be attributed to a single infection. A. marginale seemed to be important in causing the outbreak, but co-infections may have aggravated the disease development and clinical
signs. Thus, when encountering cattle with haemolytic anaemia, all of the mentioned pathogens should be included as differential
diagnosis. 相似文献
54.
Kaufmann R Fölster-Holst R Höger P Thaçi D Löffler H Staab D Bräutigam M;CASMCDE-Study Group 《The Journal of allergy and clinical immunology》2004,114(5):1183-1188
BACKGROUND: Data on the efficacy of pimecrolimus cream 1% within the first days of treatment are scarce, as in previous studies, the first postbaseline assessment was performed only after 1 week. OBJECTIVE: We sought to investigate the onset of action of pimecrolimus cream 1% in infants with mild to very severe atopic eczema. METHODS: We used pimecrolimus cream 1% (n = 129) or vehicle cream (n = 66) administered in a double-blind manner for 4 weeks and then open-label pimecrolimus cream 1% for 12 weeks, with a 4-week follow-up period. RESULTS: Pimecrolimus cream 1% reduced the mean Eczema Area and Severity Index at 4 weeks by 71.5% compared with an increase of 19.4% with vehicle ( P < .001). The reduction in the Eczema Area and Severity Index with pimecrolimus cream 1% was significant at day 4 (38.5% vs 17.6% increase with vehicle). Significant improvements in caregivers' assessments of pruritus and sleep loss were observed with pimecrolimus cream 1% by day 2 ( P < .03) and day 3 ( P = .002), respectively, compared with vehicle. Responses to pimecrolimus cream 1% were sustained during the open-label phase, and pimecrolimus cream 1% was well tolerated. Symptoms of atopic eczema returned gradually after discontinuation. CONCLUSION: Pimecrolimus cream 1% was well tolerated and effective in patients with mild to very severe atopic eczema, with rapid onset of action and no disease rebound after discontinuation. 相似文献
55.
Nascimento Jdos S Giambiagi-deMarval M de Oliveira SS Ceotto H dos Santos KR Bastos Mdo C 《Research in microbiology》2005,156(8):837-842
Among 363 strains of Staphylococcus aureus, 21 were shown to produce bacteriocins (Bac), antimicrobial peptides with potential biotechnological applications. This collection includes strains which are either isolated from food, patients and healthy cattle, or are involved in subclinical bovine mastitis. From these 21 strains, 17 were shown to carry closely-related 8.0-kb Bac plasmids encoding bacteriocins either identical to or similar to aureocin A70, a bacteriocin able to inhibit strains of Listeria monocytogenes, a food-borne pathogen. Such findings prompted us to investigate the genetic relationships among these Bac+ strains. To obtain more discriminatory results, a combined analysis of AP-PCR, rep-PCR, and a modified PCR technique that we designated SD-PCR was employed. The 17 Bac+ strains harboring 8.0-kb Bac plasmids exhibited seven fingerprint patterns. One such genotype was composed of 8 out of the 11 strains associated with bovine mastitis, which suggests the prevalence of a clone of Bac+ strains involved in this animal infection carrying 8.0-kb Bac plasmids. Our data support the assumption that Bac+ strains of S. aureus carrying genetically related 8.0-kb Bac plasmids do not belong to a single clone. It seems, therefore, that 8.0-kb Bac plasmids have spread horizontally among different S. aureus strains. There also seems to be genetic diversity among the remaining Bac+ strains analyzed. 相似文献
56.
Maya Kummrow Marina L. Meli Michael Haessig Enikoe Goenczi Amy Poland Niels C. Pedersen Regina Hofmann-Lehmann Hans Lutz 《Clinical and Vaccine Immunology : CVI》2005,12(10):1209-1215
To determine the prevalence of antibodies to feline coronavirus (FCoV) serotypes 1 and 2 in Switzerland and their association with different disease manifestations, a serological study based on immunofluorescence tests was conducted with Swiss field cats using transmissible gastroenteritis virus (TGEV), FCoV type 1 and FCoV type 2 as antigens. A total of 639 serum samples collected in the context of different studies from naturally infected cats were tested. The current study revealed that, with an apparent prevalence of 83%, FCoV serotype 1 is the most prevalent serotype in Switzerland. FCoV type 1 viruses induced higher antibody titers than FCoV type 2, and were more frequently associated with clinical signs and/or feline infectious peritonitis. The antibody development in seven cats experimentally infected with FCoV type 1 revealed that, with progressing duration of infection, antibodies to FCoV type 1 significantly increased over those to FCoV type 2. There was a significant relationship between antibody titers against TGEV, FCoV 1, and FCoV 2 and TGEV antigen detected the highest proportion of seropositive cats. We conclude that a vaccine against FCoV should be based on FCoV type 1-related antigens and that for serodiagnosis of FCoV infection TGEV should be used to attain the highest diagnostic efficiency. When serology is used in addition to clinical signs, hematology, and clinical chemistry results as an aid to diagnose clinical FIP, TGEV shows a diagnostic efficiency equal to that of a FCoV antigen. 相似文献
57.
Infant rats exhibit sensitive-period odor learning characterized by olfactory bulb neural changes and odor preference acquisitions critical for survival. This sensitive period is coincident with low endogenous corticosterone (CORT) levels and stress hyporesponsivity. The authors hypothesized that low corticosterone levels modulate sensitive-period learning. They assessed the effects of manipulating CORT levels by increasing and removing CORT during (Postnatal Day 8) and after (Postnatal Day 12) the sensitive period. Results show that (a) exogenous CORT prematurely ends sensitive-period odor-shock-induced preferences; (b) adrenalectomy developmentally extends the sensitive period as indicated by odor-shock-induced odor-preference learning in older pups, whereas CORT replacement can reinstate fear learning; and (c) CORT manipulation modulates olfactory bulb correlates of sensitive-period odor learning in a manner consistent with behavior. 相似文献
58.
Diana Gabriela Figueroa-Pia Jorge Luis Chvez-Servín Karina de la Torre-Carbot María del Carmen Caamao-Prez Gabriela Lucas-Deecke Patricia Roitman-Genoud Laura Regina Ojeda-Navarro 《Nutrition Research And Practice》2021,15(2):235
BACKGROUND/OBJECTIVESIncreasing the consumption of vegetables and fruits in Mexico remains a challenge. Promoting sustainable food production systems through schools may be an effective way to educate young people about food and nutrition issues. A study of nutritional education in adolescents, based on the school garden, is necessary in order to evaluate its effects on the consumption of fruits and vegetables among middle- and upper-income segments of the population. The objective of this study was to evaluate the effect of an educational intervention, accompanied by a school garden as an educational teaching tool, to improve vegetable and fruit consumption by Mexican teenagers attending a private middle/high school.SUBJECTS/METHODSTeenagers between 12 and 18 years of age (n = 126) attending a private middle/high school in Queretaro, Mexico participated in a 3-arm, controlled, comparative impact study using a vegetable and fruit consumption frequency questionnaire, food consumption diaries, a psychosocial factor assessment questionnaire of vegetable and fruit consumption, and structured interviews. The participants were randomized into 3 experimental groups: 1) food education + school garden (FE + SG), 2) FE only, and 3) control group (CG).RESULTSThe FE + SG and FE groups significantly increased the frequency and daily intake of vegetables and fruits compared to the CG. The FE + SG group showed greater understanding of, reflection upon, and analysis of the information they received about vegetable and fruit consumption, as well as a greater willingness to include these in their daily diet.CONCLUSIONSFE accompanied by a SG as a teaching tool is more effective at promoting vegetable and fruit consumption than either education alone or control in teenagers in middle-upper income segments of the population. 相似文献
59.
Xiaoyu Wang Mingzhen Zhang Regina R. Woloshun Yang Yu Jennifer K. Lee Shireen R. L. Flores Didier Merlin James F. Collins 《Nutrients》2021,13(5)
Intestinal iron transport requires an iron importer (Dmt1) and an iron exporter (Fpn1). The hormone hepcidin regulates iron absorption by modulating Fpn1 protein levels on the basolateral surface of duodenal enterocytes. In the genetic, iron-loading disorder hereditary hemochromatosis (HH), hepcidin production is low and Fpn1 protein expression is elevated. High Fpn1-mediated iron export depletes intracellular iron, causing a paradoxical increase in Dmt1-mediated iron import. Increased activity of both transporters causes excessive iron absorption, thus initiating body iron loading. Logically then, silencing of intestinal Dmt1 or Fpn1 could be an effective therapeutic intervention in HH. It was previously established that Dmt1 knock down prevented iron-loading in weanling Hamp (encoding hepcidin) KO mice (modeling type 2B HH). Here, we tested the hypothesis that Dmt1 silencing combined with dietary iron restriction (which may be recommended for HH patients) will mitigate iron loading once already established. Accordingly, adult Hamp KO mice were switched to a low-iron (LFe) diet and (non-toxic) folic acid-coupled, ginger nanoparticle-derived lipid vectors (FA-GDLVs) were used to deliver negative-control (NC) or Dmt1 siRNA by oral, intragastric gavage daily for 21 days. The LFe diet reduced body iron burden, and experimental interventions potentiated iron losses. For example, Dmt1 siRNA treatment suppressed duodenal Dmt1 mRNA expression (by ~50%) and reduced serum and liver non-heme iron levels (by ~60% and >85%, respectively). Interestingly, some iron-related parameters were repressed similarly by FA-GDLVs carrying either siRNA, including 59Fe (as FeCl3) absorption (~20% lower), pancreatic non-heme iron (reduced by ~65%), and serum ferritin (decreased 40–50%). Ginger may thus contain bioactive lipids that also influence iron homeostasis. In conclusion, the combinatorial approach of FA-GDLV and Dmt1 siRNA treatment, with dietary iron restriction, mitigated pre-existing iron overload in a murine model of HH. 相似文献
60.
Asher Y. Rosinger Samantha M. Olson Sascha R. Ellington Janice Perez-Padilla Regina M. Simeone Caitlin S. Pedati Betsy A. Schroeder Gilberto A. Santiago Freddy A. Medina Jorge L. Muoz-Jordn Laura E. Adams Romeo R. Galang Miguel Valencia-Prado Sonia Bakkour Candimar Coln Mary Goodwin Dana Meaney-Delman Jennifer S. Read Lyle R. Petersen Denise J. Jamieson Carmen C. Deseda Margaret A. Honein Brenda Rivera-García Carrie K. Shapiro-Mendoza 《Emerging infectious diseases》2021,27(5):1505
We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015–2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens. 相似文献