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121.
122.
A virulent Pseudomonas viridiflava-related bacterium has been identified as a new pathogen of soybean, one of the most important crops worldwide. The bacterium was recovered from forage soybean leaves with dark-reddish spots, and damage on petioles and pods was also observed. In contrast, common bean was not affected.  相似文献   
123.
Mitochondrial Ca(2+) uptake plays a fundamental role in the regulation of energy production and cell survival. Under physiological conditions, mitochondrial Ca(2+) uptake occurs by a uniport mechanism driven electrophoretically by the membrane potential created by the respiratory chain. The activity and the biochemical properties of the mitochondrial calcium uniporter (MCU) were extensively characterized for decades but the molecular identity of the channel has remained elusive. Here, we review the recent discovery of the mitochondria Ca(2+) uniporter that represents a groundbreaking result for the molecular understanding of mitochondrial Ca(2+) homeostasis and will provide insight into the role of mitochondrial Ca(2+) deregulation in the pathogenesis of human disorders.  相似文献   
124.
Twenty compounds selected as representative members of three series of long-chain 1,2-diamines, 2-amino-1-alkanols and 1-amino-2-alkanols structurally related to dihydrosphingosin, were synthesized and tested in vitro for their ability to inhibit the sleeping sickness parasites Trypanosoma bruceirhodesiense and Trypanosoma brucei gambiense. Eight compounds showed EC(50) values in the submicromolar range, with selectivity indexes up to 39 related to the respective cytotoxicity values for Vero cells. The parasite phenotype detected after treatment with the most potent compounds showed irreversible cell morphology alterations of the flagellar pocket that lead to inhibition of cell growth and parasite death.  相似文献   
125.
Maternally Inherited Diabetes and Deafness (MIDD) is a rare form of diabetes due to defects in mitochondrial DNA (mtDNA). 3243 A>G is the mutation most frequently associated with this condition, but other mtDNA variants have been linked with a diabetic phenotype suggestive of MIDD. From 1989 to 2009, we clinically diagnosed mitochondrial diabetes in 11 diabetic children. Diagnosis was based on the presence of one or more of the following criteria: 1) maculopathy; 2) hearing impairment; 3) maternal heritability of diabetes/impaired fasting glucose and/or hearing impairment and/or maculopathy in three consecutive generations (or in two generations if 2 or 3 members of a family were affected). We sequenced the mtDNA in the 11 probands, in their mothers and in 80 controls. We identified 33 diabetes-suspected mutations, 1/33 was 3243A>G. Most patients (91%) and their mothers had mutations in complex I and/or IV of the respiratory chain. We measured the activity of these two enzymes and found that they were less active in mutated patients and their mothers than in the healthy control pool. The prevalence of hearing loss (36% vs 75-98%) and macular dystrophy (54% vs 86%) was lower in our mitochondrial diabetic adolescents than reported in adults. Moreover, we found a hitherto unknown association between mitochondrial diabetes and celiac disease. In conclusion, mitochondrial diabetes should be considered a complex syndrome with several phenotypic variants. Moreover, deafness is not an essential component of the disease in children. The whole mtDNA should be screened because the 3243A>G variant is not as frequent in children as in adults. In fact, 91% of our patients were mutated in the complex I and/or IV genes. The enzymatic assay may be a useful tool with which to confirm the pathogenic significance of detected variants.  相似文献   
126.
BackgroundPopulation-based cancer registry studies of care patterns can help elucidate reasons for the marked geographic variation in cancer survival across Italy. The article provides a snapshot of the care delivered to cancer patients in Italy.MethodsRandom samples of adult patients with skin melanoma, breast, colon and non-small cell lung cancers diagnosed in 2003–2005 were selected from 14 Italian cancer registries. Logistic models estimated odds of receiving standard care (conservative surgery plus radiotherapy for early breast cancer; surgery plus chemotherapy for Dukes C colon cancer; surgery for lung cancer; sentinel node biopsy for >1 mm melanoma, vs. other treatment) in each registry compared to the entire sample (reference).ResultsStage at diagnosis for breast, colon and melanoma was earlier in north/central than southern registries. Odds of receiving standard care were lower than reference in Sassari (0.68, 95%CI 0.51–0.90) and Napoli (0.48, 95%CI 0.35–0.67) for breast cancer; did not differ across registries for Dukes C colon cancer; were higher in Romagna (3.77, 95%CI 1.67–8.50) and lower in Biella (0.38, 95%CI 0.18–0.82) for lung cancer; and were higher in Reggio Emilia (2.37, 95%CI 1.12–5.02) and lower in Ragusa (0.27, 95%CI 0.14–0.54) for melanoma.ConclusionsNotwithstanding limitations due to variations in the availability of clinical information and differences in stage distribution between north/central and southern registries, our study shows that important disparities in cancer care persist across Italy. Thus the public health priority of reducing cancer survival disparities will not be achieved in the immediate future.  相似文献   
127.

Background

Socio-economic inequalities in mortality are observed at the country level in both North America and Europe. The purpose of this work is to investigate the contribution of specific risk factors to social inequalities in cause-specific mortality using a large multi-country cohort of Europeans.

Methods

A total of 3,456,689 person/years follow-up of the European Prospective Investigation into Cancer and Nutrition (EPIC) was analysed. Educational level of subjects coming from 9 European countries was recorded as proxy for socio-economic status (SES). Cox proportional hazard model''s with a step-wise inclusion of explanatory variables were used to explore the association between SES and mortality; a Relative Index of Inequality (RII) was calculated as measure of relative inequality.

Results

Total mortality among men with the highest education level is reduced by 43% compared to men with the lowest (HR 0.57, 95% C.I. 0.52–0.61); among women by 29% (HR 0.71, 95% C.I. 0.64–0.78). The risk reduction was attenuated by 7% in men and 3% in women by the introduction of smoking and to a lesser extent (2% in men and 3% in women) by introducing body mass index and additional explanatory variables (alcohol consumption, leisure physical activity, fruit and vegetable intake) (3% in men and 5% in women). Social inequalities were highly statistically significant for all causes of death examined in men. In women, social inequalities were less strong, but statistically significant for all causes of death except for cancer-related mortality and injuries.

Discussion

In this European study, substantial social inequalities in mortality among European men and women which cannot be fully explained away by accounting for known common risk factors for chronic diseases are reported.  相似文献   
128.
129.
Monoclonal antibody (mAb) production methods (ascites, in vitro technologies, transgenic animals, and dicot or monocot transgenic plants; moss, algae) have been improved since they were first developed in 1975. In this study, we illustrate a summary of a study case in which mice, a hollow fiber system, and tobacco transgenic plants were assessed for the production of mAb for vaccine manufacturing and vaccine production.  相似文献   
130.
Mitochondria as sensors and regulators of calcium signalling   总被引:1,自引:0,他引:1  
During the past two decades calcium (Ca(2+)) accumulation in energized mitochondria has emerged as a biological process of utmost physiological relevance. Mitochondrial Ca(2+) uptake was shown to control intracellular Ca(2+) signalling, cell metabolism, cell survival and other cell-type specific functions by buffering cytosolic Ca(2+) levels and regulating mitochondrial effectors. Recently, the identity of mitochondrial Ca(2+) transporters has been revealed, opening new perspectives for investigation and molecular intervention.  相似文献   
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