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121.
Allergic responses to Aspergillus species exacerbate asthma and cystic fibrosis. The natural defense against live Aspergillus fumigatus spores or conidia depends on the recruitment and activation of mononuclear and polymorphonuclear leukocytes, events that are dependent on chemotactic cytokines. In this study, we explored the relative contribution of the monocyte chemoattractant protein-1 receptor, CCR2, in the pulmonary response to A. fumigatus conidia. Following sensitization to soluble A. fumigatus Ags, mice lacking CCR2 due to targeted deletion were markedly more susceptible to the injurious effects of an intrapulmonary challenge with live conidia compared with mice that expressed CCR2 or CCR2+/+. CCR2-/- mice exhibited a major defect in the recruitment of polymorphonuclear cells, but these mice also had significantly more eosinophils and lymphocytes in bronchoalveolar lavage samples. CCR2-/- mice also had significant increases in serum levels of total IgE and whole lung levels of IL-5, IL-13, eotaxin, and RANTES compared with CCR2+/+ mice. Airway inflammation, hyper-responsiveness to spasmogens, and subepithelial fibrosis were significantly enhanced in CCR2-/- mice compared with CCR2+/+ mice after the conidia challenge. Thus, these findings demonstrate that CCR2 plays an important role in the immune response against A. fumigatus, thereby limiting the allergic airway inflammatory and remodeling responses to this fungus.  相似文献   
122.
Tropical forests are shifting in species and trait composition, but the main underlying causes remain unclear because of the short temporal scales of most studies. Here, we develop a novel approach by linking functional trait data with 7000 years of forest dynamics from a fossil pollen record of Lake Sauce in the Peruvian Amazon. We evaluate how climate and human disturbances affect community trait composition. We found weak relationships between environmental conditions and traits at the taxon level, but strong effects for community‐mean traits. Overall, community‐mean traits were more responsive to human disturbances than to climate change; human‐induced erosion increased the dominance of dense‐wooded, non‐zoochorous species with compound leaves, and human‐induced fire increased the dominance of tall, zoochorous taxa with large seeds and simple leaves. This information can help to enhance our understanding of forest responses to past environmental changes, and improve predictions of future changes in tropical forest composition.  相似文献   
123.
Sultan S  Gosling M  Nagase H  Powell JT 《FEBS letters》2004,564(1-2):161-165
Within 6 h, shear stress upregulated intercellular adhesion molecule-1 (ICAM-1) (two- to four-fold, P<0.001) and induced matrix metalloproteinase-2 (MMP-2) in cultured human saphenous vein endothelial cells. By 8 h endothelial ICAM-1 levels returned to baseline, with concomitant increase in soluble ICAM-1 (sICAM-1) (P<0.001) and MMP-9 had been induced. Inclusion of a hydroxamate metalloproteinase inhibitor partially reversed the effects on ICAM-1 and sICAM-1 at 8 h, whereas TIMP-1, -2 or -3 had no effect. MMP-9, but not MMP-2, co-immunoprecipitated with ICAM-1. sICAM-1 was processed distal to Arg441, indicating that MMP-9, docking to ICAM-1, contributes to sICAM-1 shedding and attenuation of the shear stress-induced upregulation of ICAM-1.  相似文献   
124.
Peroxidase activity was demonstrated in extracts from hazel cotyledons and the cytoplasmic enzyme was partially characterized. Levels of cytoplasmic and org@tnellar peroxidase were monitored in seeds stratified at 5” and incubated under moist conditions at 20°. Specific activities of the enzymes in both subcellular localizations remain constant throughout nine weeks stratification but show a steady rise in activity from seeds maintained at 20°.  相似文献   
125.

Background

Over diagnosis of malaria contributes to improper treatment, wastage of drugs and resistance to the few available drugs. This paper attempts to estimate the rates of over diagnosis of malaria among children attending dispensaries in rural Tanzania and examines the potential cost implications of improving the quality of diagnosis.

Methodology/Principal Findings

The magnitude of over diagnosis of malaria was estimated by comparing the proportion of outpatient attendees of all ages clinically diagnosed as malaria to the proportion of attendees having a positive malaria rapid diagnostic test over a two month period. Pattern of causes of illness observed in a <2 year old cohort of children over one year was compared to the pattern of causes of illness in <5 year old children recorded in the routine health care system during the same period. Drug and diagnostic costs were modelled using local and international prices. Over diagnosis of malaria by the routine outpatient care system compared to RDT confirmed cases of malaria was highest among <5 year old children in the low transmission site (RR 17.9, 95% CI 5.8–55.3) followed by the ≥5 year age group in the lower transmission site (RR 14.0 95%CI 8.2–24.2). In the low transmission site the proportion of morbidity attributable to malaria was substantially lower in <2 year old cohort compared to children seen at routine care system. (0.08% vs 28.2%; p<0.001). A higher proportion of children were diagnosed with ARI in the <2 year old cohort compared to children seen at the routine care system ( 42% vs 26%; p<0.001). Using a RDT reduced overall drug and diagnostic costs by 10% in the high transmission site and by 15% in the low transmission site compared to total diagnostic and drug costs of treatment based on clinical judgment in routine health care system.

Implications

The introduction of RDTs is likely to lead to financial savings. However, improving diagnosis to one disease may lead to over diagnosis of another illness. Quality improvement is complex but introducing RDTs for the diagnosis of malaria is a good start.  相似文献   
126.
127.
A questionnaire was sent to all general practitioner principals in Leicestershire and Lincolnshire (n = 669) to determine (a) the extent to which they would participate in quality assessment activities based on objective evidence of performance and (b) the personal and professional characteristics of interested doctors. The overall response rate to the questionnaire was 76% (508 replies). The highest response rates were recorded by trainers (100%), principals in training practices (94%), and younger doctors (80-86%), the lowest by overseas graduates (59%) and older doctors (65%). Distinctive patterns of interest and participation in three types of audit activities were clearly evident. Overall, 61% (310) of respondents wished to be provided with profiles of practice activity from their family practitioner committees, 36% (183) volunteered to participate in a prescribing study, and 34% (172) expressed interest in carrying out an audit in depth. Proportionately, the most enthusiastic and active groups were trainers 88%, 70%, 62%), principals in training practices (74%, 49%, 47%), and members or fellows of the Royal College of General Practitioners (71%, 50%, 45%). Also active were younger doctors, vocationally trained doctors, and principals in large group practices. These figures suggest that roughly 15 000 general practitioners in the United Kingdom would be prepared to participate in performance review activities using information provided by external agencies, 10 000 would if they had to generate some of the information, and 7500 would if they had to produce all the information themselves.  相似文献   
128.
Four selected adults with different patterns of osteodystrophy receiving regular dialysis were treated with 1-alpha-hydroxycholecalciferol (1-alpha-OHD3) 0-5-2 mug/day for 10 to 12 months. In two patients, one with osteitis fibrosa and the other with osteomalacia, significant biochemical, radiological, and histological improvements occurred, and total body calcium measured by in-vivo neutron activation analysis increased. In two patients, in whom there were no increases of whole-body calcium, neither biochemical improvement nor healing of bone lesions occurred during the study; in one of these patients the effect of 1-alpha-OHD3 on bone resorption may have contributed to loss of body calcium and deterioration of bone disease. 1-alpha-OHD3 may therefore be a valuable adjunct in the treatment of only some patients with renal osteodystrophy. Whole-body in-vivo neutron activation seems to provide a sensitive and non-invasive index of early response to treatment.  相似文献   
129.
Liver, intestinal, and bone alkaline phosphatase isoenzymes were measured using heat stability and L-phenylalanine inhibition techniques in 78 patients on intermittent haemodialysis. Fifty-five patients had abnormalities in one or more of the isoenzymes. Changes in bone and intestinal alkaline phosphatase activities seemed to be related and raised liver isoenzyme activity was associated with the development of liver disease. Abnormal histological and radiological findings were better correlated with bone alkaline phosphatase levels than with total alkaline phosphatase, and serial estimations of bone isoenzyme activity were useful in assessing the response of renal osteodystrophy to treatment with a vitamin D analogue. Serum alkaline phosphatase isoenzyme measurement provides another useful and non-invasive index for monitoring metabolic bone disease in patients with chronic renal failure.  相似文献   
130.
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