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101.
The role of cell surface heparan sulfate in herpes simplex virus (HSV) infection was investigated using CHO cell mutants defective in various aspects of glycosaminoglycan synthesis. Binding of radiolabeled virus to the cells and infection were assessed in mutant and wild-type cells. Virus bound efficiently to wild-type cells and initiated an abortive infection in which immediate-early or alpha viral genes were expressed, despite limited production of late viral proteins and progeny virus. Binding of virus to heparan sulfate-deficient mutant cells was severely impaired and mutant cells were resistant to HSV infection. Intermediate levels of binding and infection were observed for a CHO cell mutant that produced undersulfated heparan sulfate. These results show that heparan sulfate moieties of cell surface proteoglycans serve as receptors for HSV.  相似文献   
102.

Purpose of Review

Here, we discuss the current needs and priorities for mycetoma control and prevention, highlight lessons learned from leprosy and podoconiosis, and motivate an urgent need to accelerate progress toward reducing the burden of mycetoma in endemic areas.

Recent Findings

In 2015, the World Health Assembly (WHA) added mycetoma, a progressively debilitating disease caused by fungi and bacteria, to the World Health Organization (WHO) list of priority neglected tropical diseases (NTDs). Designation of other diseases as NTDs has raised awareness, enabled global partnerships, and advanced the capacity to combat disease through integrated programming. Although key mycetoma etiologic agents have been identified, many questions remain and mycetoma may similarly benefit from NTD designation.

Summary

In collaboration with experts at WHO and elsewhere, we formed a global mycetoma working group to connect partners from a variety of sectors and specialties. We envision that this group will evolve into a formalized partnership that can prioritize strategic planning, advocacy, and research needs, identify funding sources, and coordinate activities related to mycetoma and other NTDs affecting the skin. The experiences gained from other NTDs can help to guide the global mycetoma working group’s activities to better address the goals set forth in the WHA resolution.
  相似文献   
103.
The tautomeric pair of garcinielliptone FC (GFC) is a novel tautomeric pair of polyprenyl benzophenonoid isolated from the pericarps of Garcinia subelliptica Merr. (G. subelliptica, Clusiaceae), a tree with abundant sources of polyphenols. Our previous report demonstrated that GFC induced apoptosis on various types of human cancer cell lines including chemoresistant human colorectal cancer HT‐29 cells. In the present study, we observed that many autophagy‐related genes in GFC‐treated HT‐29 cells were up‐ and down‐regulated using a cDNA microarray containing oncogenes and kinase genes. GFC‐induced autophagy of HT‐29 cells was confirmed by observing the formation of acidic vesicular organelles, LC3 puncta, and double‐membrane autophagic vesicles using flow cytometry, confocal microscopy, and transmission electron microscopy, respectively. Inhibition of AKT/mTOR/P70S6K signaling as well as formation of Atg5‐Atg12 and PI3K/Beclin‐1 complexes were observed using Western blot. Administration of autophagy inhibitor (3‐methyladenine and shRNA Atg5) and apoptosis inhibitor Z‐VAD showed that the GFC‐induced autophagy was cytotoxic form and GFC‐induced apoptosis enhanced GFC‐induced autophagy. Our data suggest the involvement of autophagy and apoptosis in GFC‐induced anticancer mechanisms of human colorectal cancer.  相似文献   
104.
105.
Geiger DR  Shieh WJ  Yu XM 《Plant physiology》1995,107(2):507-514
A high rate of daytime export of assimilated carbon from leaves of a starch-deficient mutant tobacco (Nicotiana sylvestris L.) was found to be a key factor that enabled shoots to grow at rates comparable to those in wild-type plants under a 14-h light period. Much of the newly fixed carbon that would be used for starch synthesis in leaves of wild-type plants was used instead for sucrose synthesis in the mutant. As a result, export doubled and accumulation of sucrose and hexoses increased markedly during the day in leaves of the mutant plants. The increased rate of export to sink leaves appeared to be responsible for the increase in the proportion of their growth that occurred during the day compared to wild-type plants. Daytime growth of source leaves also increased, presumably as a result of the increased accumulation of recently assimilated soluble carbon in the leaves. Even though starch accumulation did not occur in the leaves of mutant plants, nearly all the sugar that accumulated during the day was exported in the period of decreasing irradiance at the end of the diurnal light period. Changes in carbon allocation that occurred in leaves of wild-type and mutant plants near the end of the light period appeared to result from endogenous diurnal regulation associated with the day-night transition.  相似文献   
106.

Purpose

The purpose of this study was to develop a reliable and valid instrument, named the Observatory Test of Capacity, Performance, and Developmental Disregard (OTCPDD), for measuring the amount and quality of use of affected upper limb functions in the daily routines of children with CP.

Methods

Forty-eight participants (24 children with CP and 24 matched typically developing children) were recruited. The OTCPDD was administered twice (the spontaneous use condition first, followed by the forced use condition) on children with CP. Their parents were asked to complete the Pediatric Motor Activity Log-Revised (PMAL-R). The internal consistency, the intrarater and interrater reliabilities, and the convergent and discriminate validities were measured.

Results

The internal consistency (Cronbach’s alpha) and the intrarater and interrater reliabilities were higher than 0.9 for all of the OTCPDD scores. The convergent validity was confirmed by significant correlations between the OTCPDD and the PMAL-R. For the discriminant validity, significant differences (p<0.05) were found between children with CP and typically developing children.

Conclusions

The results support that the OTCPDD is a reliable and valid observation-based assessment. The OTCPDD, which uses bimanual daily living activities, is able to represent the children’s general affected hand functions (including capacity, performance, and developmental disregard) in their daily routines.  相似文献   
107.
108.
J. Barber  Y. J. Shieh 《Planta》1973,111(1):13-22
Summary The rate of Na+/Na+ exchange as measured with 24Na+ in Na+-rich cells of Chlorella pyrenoidosa is governed by a single rate constant and saturates with increasing external Na+ concentration. The K mvalue for this process is 0.8 mM Na+ and the maximum rate of exchange in illuminated cells is about 5 pmoles cm-2 sec-1. These values contrast with a K mof 0.18 mM K+ and maximum rate of about 17 pmoles K+·cm-2·sec-1 for net K+ influx. Although the Na+/Na+ exchange was only slightly sensitive to light it was inhibited by the uncouplers CCCP and DNP and by the energy transfer inhibitor DCCD. This inhibition of the rate of Na+/Na+ exchange was not accompanied by a loss of internal Na+. Both the effect of external K+ on 24Na+ influx into Na+-rich cells and the inhibition of net K+ uptake by the presence of external Na+ indicates that Na+/Na+ and K+/Na+ exchanges share the same carrier and that the external site of this carrier has a three to four times higher affinity for K+ over Na+.  相似文献   
109.
华南鱼藤的分析及毒力试验   总被引:4,自引:0,他引:4  
一、绪言 鱼藤(Derris)是一种优良的植物质杀虫剂,对多数害虫有毒杀的效力,而对人畜无害,对作物亦绝不发生药害,同时更不影响作物固有的风味,为近代综合有机杀虫药剂所不能及的。鱼藤为各国普遍所采用,尤其对一般园艺作物害虫的防治,更受欢迎。鱼藤在我国除台湾在日伪时代曾大量推广繁殖,从事专业栽培外;  相似文献   
110.
The sequences of four naturally occurring luteinizing hormone releasing hormones (LHRH's) differ only in positions 5, 7 and 8. Salmon and chicken II LHRH's have Trp7; porcine/ovine (P/O) and chicken I LHRH's have Leu7. The receptor for P/O LHRH might effectively bind certain antagonists with Trp7. Thirteen antagonists having Trp7 and eight antagonists with other substitutions in position 7 were synthesized. One of the thirteen antagonists with the natural Trp7, [N-Ac-D-2-Nal1,D-pClPhe2,D-3-Pal3,D-Arg6,Trp7,D- Ala10]-LHRH, not only maintained activity, but had increased potency (ca. 58%; 90% antiovulatory activity/250 ng; rats) in comparison with the companion analog with the natural Leu7 of P/O LHRH. The other twelve Trp7-antagonists had lower potency.  相似文献   
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