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991.
WJ Calhoun BT Ameredes TS King N Icitovic ER Bleecker M Castro RM Cherniack VM Chinchilli T Craig L Denlinger EA DiMango LL Engle JV Fahy JA Grant E Israel N Jarjour SD Kazani M Kraft SJ Kunselman SC Lazarus RF Lemanske N Lugogo RJ Martin DA Meyers WC Moore R Pascual SP Peters J Ramsdell CA Sorkness ER Sutherland SJ Szefler SI Wasserman MJ Walter ME Wechsler HA Boushey;Asthma Clinical Research Network of the National Heart Lung Blood Institute 《JAMA : the journal of the American Medical Association》2012,308(10):987-997
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de Almeida CM de Lima TA Castro DB Torres KL da Silva Braga W Peruhype-Magalhães V Teixeira-Carvalho A Martins-Filho OA Malheiro A 《Scandinavian journal of immunology》2011,73(5):486-495
The rational of this study we intended to investigate whether the peripheral blood immunological/virological biomarkers were associated with distinct patterns of sleeping quality in patients with chronic hepatitis C-(HCV). Distinct well-established indexes/scores were used to categorize the sleeping quality of HCV patients, including the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale and Fatigue Severity Scores. Our findings demonstrated that HCV patients classified as 'good sleeper' displayed an enhanced frequency of circulating CD8(+) T cells, lower frequency of activated (CD69(+)) neutrophils and eosinophils but enhanced frequency of activated lymphocytes besides lower seric levels of IL-4/IL-8/IL-10 but higher levels of IL-12, besides lower HCV virus load and lower anti-HCV IgG levels. In contrast, HCV patients classified as 'poor sleeper' displayed enhanced levels of activated neutrophils and eosinophils but lower frequency of activated lymphocytes, higher seric levels of IL-6/TNF-α/IL-10 but lower levels of IL-12 besides higher HCV virus load and increased anti-HCV IgG levels. Positive correlation was further confirmed by the relationship between the leucocyte activation status, the cytokine levels, the HCV viral load and the anti-HCV IgG reactivity with the PSQI indexes. Analysis of cytokine signature curves demonstrated that lower frequency of IL-10 was observed in HCV patients classified as 'good sleepers', whereas enhanced frequency of IL-6 was found HCV patients classified as 'poor sleepers'. In conclusion, our data suggest that immunological biomarkers (leucocytes activation status and seric cytokines levels) are likely to be associated with sleeping quality patterns in HCV patients, suggesting their putative use for clinical monitoring purposes. 相似文献
996.
Gerding WM Schreiber S Schulte-Middelmann T de Castro Marques A Atorf J Akkad DA Dekomien G Kremers J Dermietzel R Gal A Rülicke T Ibrahim S Epplen JT Petrasch-Parwez E 《Human molecular genetics》2011,20(18):3620-3631
Retinitis pigmentosa (RP) is a group of human retinal disorders, with more than 100 genes involved in retinal degeneration. Canine and murine models are useful for investigating human RP based on known, naturally occurring mutations. In Schapendoes dogs, for example, a mutation in the CCDC66 gene has been shown to cause autosomal recessively inherited, generalized progressive retinal atrophy (gPRA), the canine counterpart to RP. Here, a novel mouse model with a disrupted Ccdc66 gene was investigated to reveal the function of protein CCDC66 and the pathogenesis of this form of gPRA. Homozygous Ccdc66 mutant mice lack retinal Ccdc66 RNA and protein expression. Light and electron microscopy reveal an initial degeneration of photoreceptors already at 13 days of age, followed by a slow, progressive retinal degeneration over months. Retinal dysfunction causes reduced scotopic a-wave amplitudes, declining from 1 to 7 months of age as well as an early reduction of the photopic b-wave at 1 month, improving slightly at 7 months, as evidenced by electroretinography. In the retina of the wild-type (WT) mouse, protein CCDC66 is present at highest levels after birth, followed by a decline until adulthood, suggesting a crucial role in early development. Protein CCDC66 is expressed predominantly in the developing rod outer segments as confirmed by subcellular analyses. These findings illustrate that the lack of protein CCDC66 causes early, slow progressive rod-cone dysplasia in the novel Ccdc66 mutant mouse model, thus providing a sound foundation for the development of therapeutic strategies. 相似文献
997.
Tang Y Quintana M Zhang C Li T Sauls D Putnak R Alvarado SC Castro DJ Matute ML Lynch JA 《Virus genes》2011,42(2):200-203
Eight serum specimens collected from dengue patients in Guatemala and Honduras during the Central American epidemic of 2007
were analyzed. Virus identification and serotyping performed by a nested RT-PCR assay revealed two DENV-1 isolates from Guatemala,
four DENV-2 isolates, two each from Guatemala and Honduras, and two DENV-4 isolates from Honduras. Viral genotyping determined
by phylogenetic analysis of the complete envelope gene sequences demonstrated that the DENV-2 isolates from Guatemala and
Honduras fell into the American/Asian Genotype III, and were most closely related to DENV-2/NI/BID-V2683-1999 isolated from
a dengue case in Nicaragua in 1999; and the DENV-4 F07-076 isolate from Honduras belonged to genotype II, and was most closely
related to DENV-4/US/BID-V1093/1998 isolated from Puerto Rico in 1998. Our results suggest that the 2007 dengue outbreaks
in Guatemala and Honduras were most likely caused by the re-emergence of earlier, indigenous DENV strains rather than by newly
introduced strains and there were at least three serotypes of DENV co-circulating during the 2007 Central American epidemics. 相似文献
998.
Pinheiro Ide O de Castro MF Mitterofhe A Pires FA Abramo C Ribeiro LC Tibiriçá SH Coimbra ES 《Parasitology research》2011,108(5):1123-1130
Giardiasis and soil-transmitted helminthiasis (STH) are parasitic diseases that are among the major health concerns observed
in economically disadvantaged populations of developing countries, and have clear social and environmental bases. In Brazil,
there is a lack of epidemiologic data concerning these infections in the study area, whose inhabitants have plenty of access
to health care services, including good dwelling and adequate sanitary conditions. In this survey we investigated the risk
factors for giardiasis and STH in three municipalities with good sanitation, situated in Minas Gerais state, Brazil. A cross-sectional
survey was conducted in the municipalities of Piau, Coronel Pacheco and Goianá, in both urban and rural areas. The fieldwork
consisted of a questionnaire and the examination of 2,367 stool samples using the Hoffmann, Pons and Janer method. Of all
individuals from the population sample, 6.1% were found infected with the parasitic diseases included in this work. Hookworm
infection was the most prevalent disease, followed by giardiasis, trichuriasis and ascariasis. Infection was more prevalent
in males (8.1%, p < 0.001; odds ratio [OR] = 1.975) and in individuals living in rural areas (8.6%, p = 0.003; OR = 1.693). Multivariate analysis showed that variables such as inadequate sewage discharge (p < 0.001), drinking of unsafe water (p < 0.001), lack of sanitary infrastructure (p = 0.015), and host sex (p < 0.001) were the risk factors more strongly associated with infection status (95% confidence interval [CI]). In this study
we demonstrate that giardiasis and STH still persist, infecting people who have good housing conditions and free access to
public health care and education. 相似文献
999.
Aguiar AS Castro AA Moreira EL Glaser V Santos AR Tasca CI Latini A Prediger RD 《Mechanisms of ageing and development》2011,132(11-12):560-567
In the present study, we investigated whether mild-intensity physical exercise represents a successful strategy to enhance spatial learning and memory and hippocampal plasticity in aging rats, as previously described for long-term exposure to running wheel or treadmill exercise. Aging Wistar rats were submitted to short bouts (4-6 min) of exercise treadmill during five consecutive weeks. This mild-intensity exercise program increased muscle oxygen consumption by soleus and heart in aging rats and reversed age-related long-term spatial learning and memory impairments evaluated in the water maze and step-down inhibitory avoidance tasks. Remarkably, the observed cognitive-enhancing properties of short bouts of exercise were accompanied by the activation of serine/threonine protein kinase (AKT) and cAMP response element binding (CREB) pro-survival signaling that culminates in the marked increase on the brain-derived neurotrophic factor (BDNF) mRNA expression and BDNF protein levels on the hippocampus of aging rats. Altogether, these results indicate that short bouts of exercise represent a viable behavioral strategy to improve cognition and synaptic plasticity in aging rats which should be taken into account in further studies addressing the effects of physical exercise in aging subjects. 相似文献
1000.
de Oliveira RR de Lira KD Silveira PV Coutinho MP Medeiros MN Teixeira MF de Moraes SR 《Annals of biomedical engineering》2011,39(5):1528-1534
The aim of this study was to quantify the effect of chemically induced diabetes mellitus (DM) on the mechanical properties
of the Achilles tendon of rats and correlate it with metabolic and biomechanical findings. Adult rats were selected randomly
and assigned to two groups, the diabetic group consisted of animals receiving a dose of streptozotocin to induce type I diabetes
and the control group. The animals were placed in metabolic cages for analysis of metabolism. Ten weeks after diabetes induction,
the Achilles tendon of both groups were collected and submitted to a traction test in a conventional testing machine. The
measurements of mechanical properties indicated that the elastic modulus (MPa) was significantly higher in the control group
(p < 0.01). In Maximum tension (MPa), the groups did not have differences (p > 0.01). Energy/tendon area (N mm/mm2), specific strain (%) and maximum specific strain (mm) were higher in tendon tests of the diabetic group (p < 0.01). We observed that the mechanical properties of tendons have correlations with metabolic properties of the diabetic
animals. These results showed that induced DM in rats have an important negative effect on the mechanical properties of the
Achilles tendon. 相似文献