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1.

Background  

The integration of many aspects of protein/DNA structure analysis is an important requirement for software products in general area of structural bioinformatics. In fact, there are too few software packages on the internet which can be described as successful in this respect. We might say that what is still missing is publicly available, web based software for interactive analysis of the sequence/structure/function of proteins and their complexes with DNA and ligands. Some of existing software packages do have certain level of integration and do offer analysis of several structure related parameters, however not to the extent generally demanded by a user.  相似文献   
2.

Background  

Pichia pastoris has been recognized as an effective host for recombinant protein production. A number of studies have been reported for improving this expression system. However, its physiology and cellular metabolism still remained largely uncharacterized. Thus, it is highly desirable to establish a systems biotechnological framework, in which a comprehensive in silico model of P. pastoris can be employed together with high throughput experimental data analysis, for better understanding of the methylotrophic yeast's metabolism.  相似文献   
3.
A taxonomic survey was conducted to determine the microbial diversity held within the Harbor Branch Oceanographic Marine Microbial Culture Collection (HBMMCC). The collection consists of approximately 17,000 microbial isolates, with 11,000 from a depth of greater than 150 ft seawater. A total of 2273 heterotrophic bacterial isolates were inventoried using the DNA fingerprinting technique amplified rDNA restriction analysis on approximately 750-800 base pairs (bp) encompassing hypervariable regions in the 5' portion of the small subunit (SSU) 16S rRNA gene. Restriction fragment length polymorphism patterns obtained from restriction digests with RsaI, HaeIII, and HhaI were used to infer taxonomic similarity. SSU 16S rDNA fragments were sequenced from a total of 356 isolates for more definitive taxonomic analysis. Sequence results show that this subset of the HBMMCC contains 224 different phylotypes from six major bacterial clades (Proteobacteria (Alpha, Beta, Gamma), Cytophaga, Flavobacteria, and Bacteroides (CFB), Gram + high GC content, Gram + low GC content). The 2273 microorganisms surveyed encompass 834 alpha-Proteobacteria (representing 60 different phylotypes), 25 beta-Proteobacteria (3 phylotypes), 767 gamma-Proteobacteria (77 phylotypes), 122 CFB (17 phylotypes), 327 Gram + high GC content (43 phylotypes), and 198 Gram + low GC content isolates (24 phylotypes). Notably, 11 phylotypes were < or =93% similar to the closest sequence match in the GenBank database even after sequencing a larger portion of the 16S rRNA gene (approximately 1400 bp), indicating the likely discovery of novel microbial taxa. Furthermore, previously reported "uncultured" microbes, such as sponge-specific isolates, are part of the HBMMCC. The results of this research will be available online as a searchable taxonomic database (www.hboi.edu/dbmr/dbmr_hbmmd.html).  相似文献   
4.
5.
This commentary highlights the effectiveness of optoelectronic properties of polymer semiconductors based on recent results emerging from our laboratory, where these materials are explored as artificial receptors for interfacing with the visual systems. Organic semiconductors based polymer layers in contact with physiological media exhibit interesting photophysical features, which mimic certain natural photoreceptors, including those in the retina. The availability of such optoelectronic materials opens up a gateway to utilize these structures as neuronal interfaces for stimulating retinal ganglion cells. In a recently reported work entitled “A polymer optoelectronic interface provides visual cues to a blind retina,” we utilized a specific configuration of a polymer semiconductor device structure to elicit neuronal activity in a blind retina upon photoexcitation. The elicited neuronal signals were found to have several features that followed the optoelectronic response of the polymer film. More importantly, the polymer-induced retinal response resembled the natural response of the retina to photoexcitation. These observations open up a promising material alternative for artificial retina applications.  相似文献   
6.

Background

Influenza pandemic remains a serious threat to human health. Viruses of avian origin, H5N1, H7N7 and H9N2, have repeatedly crossed the species barrier to infect humans. Recently, a novel strain originated from swine has evolved to a pandemic. This study aims at improving our understanding on the pathogenic mechanism of influenza viruses, in particular the role of non-structural (NS1) protein in inducing pro-inflammatory and apoptotic responses.

Methods

Human lung epithelial cells (NCI-H292) was used as an in-vitro model to study cytokine/chemokine production and apoptosis induced by transfection of NS1 mRNA encoded by seven infleunza subtypes (seasonal and pandemic H1, H2, H3, H5, H7, and H9), respectively.

Results

The results showed that CXCL-10/IP10 was most prominently induced (> 1000 folds) and IL-6 was slightly induced (< 10 folds) by all subtypes. A subtype-dependent pattern was observed for CCL-2/MCP-1, CCL3/MIP-1α, CCL-5/RANTES and CXCL-9/MIG; where induction by H5N1 was much higher than all other subtypes examined. All subtypes induced a similar temporal profile of apoptosis following transfection. The level of apoptosis induced by H5N1 was remarkably higher than all others. The cytokine/chemokine and apoptosis inducing ability of the 2009 pandemic H1N1 was similar to previous seasonal strains.

Conclusions

In conclusion, the NS1 protein encoded by H5N1 carries a remarkably different property as compared to other avian and human subtypes, and is one of the keys to its high pathogenicity. NCI-H292 cells system proves to be a good in-vitro model to delineate the property of NS1 proteins.
  相似文献   
7.
The heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo[4,5-B]pyridine (PhIP), found in meats cooked at high temperatures, has been implicated in epidemiological and rodent studies for causing breast, prostate, and colorectal cancers. A previous animal study using a xenograft model has shown that whole tomato and broccoli, when eaten in combination, exhibit a marked effect on tumor reduction compared to when eaten alone. Our aim was to determine if PhIP-induced carcinogenesis can be prevented by dietary consumption of whole tomato + broccoli powders. Male Fischer 344 rats (n = 45) were randomized into the following treatment groups: control (AIN93G diet), PhIP (200 ppm in AIN93G diet for the first 20 weeks of the study), or tomato + broccoli + PhIP (mixed in AIN93G diet at 10% each and fed with PhIP for 20 weeks, and then without PhIP for 32 weeks). Study animals were monitored for 52 weeks and were euthanized as necessary based on a set of criteria for health status and tumor burden. Although there appeared to be some hepatic and intestinal toxicity due to the combination of PhIP and tomato + broccoli, these rodents had improved survival and reduced incidence and/or severity of PhIP-induced neoplastic lesions compared to the PhIP-alone treated group. Rats eating tomato + broccoli exhibited a marked decrease in the number and size of cribiform prostatic intraepitheilial neoplasia/carcinoma in situ (cribiform PIN/CIS) lesions and in the incidence of invasive intestinal adenocarcinomas and skin carcinomas. Although the apparent toxic effects of combined PhIP and tomato + broccoli need additional study, the results of this study support the hypothesis that a diet rich in tomato and broccoli can reduce or prevent dietary carcinogen-induced cancers.  相似文献   
8.
Purinergic Signalling - P2 purinergic receptors are involved in the normal function of the kidney, bladder, and prostate via signaling that occurs in response to extracellular nucleotides....  相似文献   
9.
Earlier opinions that Macroramphosus is monotypic are refuted, with two species apparently occurring in Japan (tentatively identified as M. gracilis and M. scolopax). In postsettlement young and adults, the former is characterized by a dark slender body (vs. red-orange and deep) and short second dorsal fin spine with a smooth posterior margin (vs. long spine with a serrated margin). Food habits also differ between the two species, which are either plankton or benthos feeders. Two types of Macroramphosus larvae and juveniles occurring at the surface were recognized, one having a straight ventral body profile of the body (identified here as M. gracilis) and the other having a notch in the anal region. The dark body of postsettlement M. gracilis is considered to be a retention of the character suited to the neustonic distribution of the larval and juvenile stages, the species remaining to ca. 40mm in standard length (SL) in that habitat (vs. to ca. 12mm SL in M. scolopax).  相似文献   
10.
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