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61.
BackgroundCameroon achieved the elimination target of leprosy in 2000, and has maintained this status ever since. However, a number of health districts in the country continue to report significant numbers of leprosy cases. The aim of this study was to assess the burden of leprosy in Cameroon from 2000 to 2014.MethodsWe obtained and analysed using the new leprosy burden concept of analysis, leprosy surveillance data collected between 2000 and 2014 from the National Leprosy Control Programme.ConclusionThe leprosy prevalence and detection rates as well as the overall leprosy burden in Cameroon have dropped significantly between 2000 and 2014. However, a good number of health districts remain high-leprosy-burdened. The National Leprosy Control Programme should focus efforts on these health districts in the next coming years in order to further reduce the burden of leprosy in the country.  相似文献   
62.
The fat mass and obesity‐associated (FTO) gene was genotyped for the participants in the Dose‐Response to Exercise in postmenopausal Women (DREW) trial and analyses were performed to determine whether an FTO variant was associated with adiposity and cardiorespiratory fitness (CRF) before and after 6 months of moderate intensity exercise in white women (n = 234). The A/A homozygotes for rs8050136 had a higher BMI (kg/m2) compared to C/C homozygotes at baseline (32.8 (0.6) vs. 31.0 (0.4), respectively; P < 0.05) and at follow‐up (31.9 (0.6) vs. 30.4 (0.5), respectively; P < 0.05). Weight loss occurred after exercise, but there was no significant genotype by exercise interaction over time. Exploratory analyses among women exposed to moderate intensity exercise meeting, or exceeding, the physical activity recommendation found that those homozygous A/A lost significantly more weight than the C allele carriers (?3.3 (0.7) kg vs. ?1.4 (0.4) kg and ?1.5 (0.5) kg, respectively; P < 0.05). CRF, defined as VO2peak (oxygen consumption), increased after exercise and the magnitude of the increase was similar for each genotype. In conclusion, women genetically predisposed to being obese experienced weight loss and CRF benefits with moderate intensity exercise, with additional weight loss observed when the women met or exceeded the physical activity recommendations.  相似文献   
63.
Based on their extracellular expression and targeting of the clock gene Bmal1, miR-142-3p and miR-494 were analyzed for evidence of vesicle-mediated communication between cells and intracellular functional activity. Our studies demonstrate that: miR-142-3p + miR-494 overexpression decreases endogenous BMAL1 levels, increases the period of Per2 oscillations, and increases extracellular miR-142-3p/miR-494 abundance in conditioned medium; miRNA-enriched medium increases intracellular expression of miR-142-3p and represses Bmal1 3′-UTR activity in naïve cells; and inhibitors of vesicular trafficking modulate intercellular communication of these miRNAs and ensemble Per2 rhythms. Thus, miR-142-3p and miR-494 may function as cis- and trans-acting signals contributing to local temporal coordination of cell-autonomous circadian clocks.  相似文献   
64.
LEUNGTM  PLLIM 《Cell research》1990,1(2):217-221
One of the earliest events leading to cell activation and growth is the hydrolysis of inositol phospholipids producing various membrane signals induced by an interaction between growth factors or hormones with their respective receptors on the cell membrane [1].To demonstrate the mitogenic action of transferrin,our results show that an addition of transferrin to “serum-deprived” rat hepatoma cells produced a rapid but transient rise in inositol 1,4,5-trisphosphate(IP3) level,and at the same time,an increased intracellular Ca^2 activity and a cytoplasmic alkalinization were observed.These signal transductions further lend support to the mitogenic nature of transferrin.In addition,a possible link between the receptor-mediated endocytosis of transferrin with the generation of intracellular signals is discussed herewith.  相似文献   
65.

Background  

Biclustering has emerged as a powerful algorithmic tool for analyzing measurements of gene expression. A number of different methods have emerged for computing biclusters in gene expression data. Many of these algorithms may output a very large number of biclusters with varying degrees of overlap. There are no systematic methods that create a two-dimensional layout of the computed biclusters and display overlaps between them.  相似文献   
66.

Background

Although personal cigarette smoking is the most important cause and modulator of chronic obstructive pulmonary disease (COPD), secondhand smoke (SHS) exposure could influence the course of the disease. Despite the importance of this question, the impact of SHS exposure on COPD health outcomes remains unknown.

Methods

We used data from two waves of a population-based multiwave U.S. cohort study of adults with COPD. 77 non-smoking respondents with a diagnosis of COPD completed direct SHS monitoring based on urine cotinine and a personal badge that measures nicotine. We evaluated the longitudinal impact of SHS exposure on validated measures of COPD severity, physical health status, quality of life (QOL), and dyspnea measured at one year follow-up.

Results

The highest level of SHS exposure, as measured by urine cotinine, was cross-sectionally associated with poorer COPD severity (mean score increment 4.7 pts; 95% CI 0.6 to 8.9) and dyspnea (1.0 pts; 95% CI 0.4 to 1.7) after controlling for covariates. In longitudinal analysis, the highest level of baseline cotinine was associated with worse COPD severity (4.7 points; 95% CI -0.1 to 9.4; p = 0.054), disease-specific QOL (2.9 pts; -0.16 to 5.9; p = 0.063), and dyspnea (0.9 pts; 95% CI 0.2 to 1.6 pts; p < 0.05), although the confidence intervals did not always exclude the no effect level.

Conclusion

Directly measured SHS exposure appears to adversely influence health outcomes in COPD, independent of personal smoking. Because SHS is a modifiable risk factor, clinicians should assess SHS exposure in their patients and counsel its avoidance. In public health terms, the effects of SHS exposure on this vulnerable subpopulation provide a further rationale for laws prohibiting public smoking.  相似文献   
67.
68.
Three new dinoflagellate species, Karenia papilionacea sp. nov., Karenia selliformis sp. nov., and Karenia bidigitata sp. nov., were compared with the toxic species Karenia mikimotoi (Miyake & Kominami ex Oda) G. Hansen & Moestrup, Karenia brevis (Davis) G. Hansen & Moestrup, and Karenia brevisulcata (Chang) G. Hansen & Moestrup using the same fixative. Distinguishing morphological characters for the genus Karenia included a smooth theca and a linear apical groove. The new species can be distinguished on the basis of morphological characters of vegetative cells that include the location and shape of the nucleus; the relative excavation of the hypotheca; the characteristics of apical and sulcal groove extensions on the epitheca; the cellular shape, size, and symmetry; the degree of dorsoventral compression; and the presence of an apical protrusion or carina. Species with pronounced dorsoventral compression swim in a distinctive fluttering motion. An intercingular tubular structure traversing the proximal and distal ends of the cingulum is common to the species of Karenia, Karlodinium micrum (Leadbeater & Dodge) J. Larsen, Gymnodinium pulchellum J. Larsen, and Gyrodinium corsicum Paulmier. Molecular phylogenetic analyses of rDNA sequence alignments show that the new species are phylogenetically distinct but closely related to K. mikimotoi and K. brevis.  相似文献   
69.
70.
Two of the four WNK (with no lysine (K)) protein kinases are associated with a heritable form of ion imbalance culminating in hypertension. WNK1 affects ion transport in part through activation of the closely related Ste20 family protein kinases oxidative stress-responsive 1 (OSR1) and STE20/SPS1-related proline-, alanine-rich kinase (SPAK). Once activated by WNK1, OSR1 and SPAK phosphorylate and stimulate the sodium, potassium, two chloride co-transporters, NKCC1 and NKCC2, and also affect other related ion co-transporters. We find that WNK1 and OSR1 co-localize on cytoplasmic puncta in HeLa and other cell types. We show that the C-terminal region of WNK1 including a coiled coil is sufficient to localize the fragment in a manner similar to the full-length protein, but some other fragments lacking this region are mislocalized. Photobleaching experiments indicate that both hypertonic and hypotonic conditions reduce the mobility of GFP-WNK1 in cells. The four WNK family members can phosphorylate the activation loop of OSR1 to increase its activity with similar kinetic constants. C-terminal fragments of WNK1 that contain three RFXV interaction motifs can bind OSR1, block activation of OSR1 by sorbitol, and prevent the OSR1-induced enhancement of ion co-transporter activity in cells, further supporting the conclusion that association with WNK1 is required for OSR1 activation and function at least in some contexts. C-terminal WNK1 fragments can be phosphorylated by OSR1, suggesting that OSR1 catalyzes feedback phosphorylation of WNK1.  相似文献   
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