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21.
Aspergillus tamarii expresses an extracellular alkaline protease that we show to be effective in removing hair from cattle hide. Large quantities of the enzyme will be required for the optimization of the enzymatic dehairing process so the growth conditions for maximum protease expression by A. tamarii were optimized for both solid-state culture on wheat bran and for broth culture. Optimal protease expression occurred, for both cultural media, at initial pH 9; the culture was incubated at 30 °C for 96 h using a 5% inoculum. The crude enzyme was isolated, purified and characterized using MALDI TOF TOF. The alkaline protease was homologous to the alkaline protease expressed by Aspergillus viridinutans. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture.  相似文献   
22.
Incorporation of an adamantyl group in prototypical soluble expoxide hydrolase (sEH) inhibitors afforded improved enzyme potency. We explored replacement of the adamantyl group in unsymmetrical ureas and amides with substituted aryl rings to identify equipotent and metabolically stable sEH inhibitors. We found that aryl rings, especially those substituted in the para position with a strongly electron withdrawing substituent, afforded enzyme IC50 values comparable to the adamantyl compounds in an ether substituted, unsymmetrical N,N′-diaryl urea or amide scaffold.  相似文献   
23.
A series of 2-(1,4′-bipiperidine-1′-yl)thiazolopyridines was synthesized and evaluated as a new lead of non-imidazole histamine H3 receptor antagonists. Introduction of diversity at the 6-position of the pyridine ring was designed to enhance in vitro potency and decrease hERG activity. The structure–activity relationships for these new thiazolopyridine antagonists are discussed.  相似文献   
24.
Melanin concentrating hormone (MCH) receptor antagonists have been proposed as potential treatments of obesity. MCH receptor antagonists with a biphenylamine subunit have been reported previously at Schering-Plough. Herein, we report the discovery of bicyclo[4.1.0]heptanes as replacements for the middle phenyl ring of the biphenylamine moiety in order to eliminate its potential mutagenic liability. Structure-activity relationships in this series were found to be very similar to those of the original biphenylamine series, suggesting that the two series have similar binding modes.  相似文献   
25.

Background

Avian paramyxoviruses (APMV) consist of nine known serotypes. The genomes of representatives of all APMV serotypes except APMV type 5 have recently been fully sequenced. Here, we report the complete genome sequence of the APMV-5 prototype strain budgerigar/Kunitachi/74.

Methodology/Principal Findings

APMV-5 Kunitachi virus is unusual in that it lacks a virion hemagglutinin and does not grow in the allantoic cavity of embryonated chicken eggs. However, the virus grew in the amniotic cavity of embryonated chicken eggs and in twelve different established cell lines and two primary cell cultures. The genome is 17,262 nucleotides (nt) long, which is the longest among members of genus Avulavirus, and encodes six non-overlapping genes in the order of 3′N-P/V/W-M-F-HN-L-5′ with intergenic regions of 4–57 nt. The genome length follows the ‘rule of six’ and contains a 55-nt leader sequence at the 3′end and a 552 nt trailer sequence at the 5′ end. The phosphoprotein (P) gene contains a conserved RNA editing site and is predicted to encode P, V, and W proteins. The cleavage site of the F protein (G-K-R-K-K-R↓F) conforms to the cleavage site motif of the ubiquitous cellular protease furin. Consistent with this, exogenous protease was not required for virus replication in vitro. However, the intracerebral pathogenicity index of APMV-5 strain Kunitachi in one-day-old chicks was found to be zero, indicating that the virus is avirulent for chickens despite the presence of a polybasic F cleavage site.

Conclusions/Significance

Phylogenetic analysis of the sequences of the APVM-5 genome and proteins versus those of the other APMV serotypes showed that APMV-5 is more closely related to APMV-6 than to the other APMVs. Furthermore, these comparisons provided evidence of extensive genome-wide divergence that supports the classification of the APMVs into nine separate serotypes. The structure of the F cleavage site does not appear to be a reliable indicator of virulence among APMV serotypes 2–9. The availability of sequence information for all known APMV serotypes will facilitate studies in epidemiology and vaccinology.  相似文献   
26.
Herein, we report the discovery of the potent and selective biaryl diamide derived MCH-R1 receptor antagonist 1, which was identified upon modification of a previously disclosed biaryl urea series. This paper describes one of the strategies incorporated to remove the highly mutagenic biarylaniline present in an otherwise promising biaryl urea series.  相似文献   
27.
Diabetes mellitus (DM) is a common metabolic illness defined by hyperglycemia caused by insufficient production or absent of pancreatic insulin, with or without concomitant insulin action impairment. Hence, novel problem-solving approaches for assessing early metabolic diseases, notably insulin resistance, are urgently needed. Screening of natural compounds for drug discovery to combat diabetes is common in modern medical research and development. Therefore, it is of interest to document the molecular docking analysis data of beta-Caryophyllene, a naturally occurring sequiterpene with the downstream insulin signaling molecules such as IRS-1, cSrc and Akt for the management of type-2 diabetes. The molecular docking analysis data of beta-caryophyllene with the insulin downstream signaling molecules such as IRS-1, cSrc and Akt reveals its ability and further studies are needed to elucidate its complete mechanism of action against type-2 diabetes.  相似文献   
28.
29.
Aging has been defined as the changes that occur in living organisms with the passage of time that lead to functional impairment and ultimately to death. Free radical-induced oxidative damage has long been thought to be the most important consequence of the aging process. In the present study, an attempt has been made to study the salubrious effects of dietary supplementation of chitosan on glutathione-dependent antioxidant defense system in young and aged rats. The dietary supplementation of chitosan significantly reduced the age-associated dyslipidemic abnormalities noted in the levels of total cholesterol, HDL-cholesterol, and LDL-cholesterol in plasma and heart tissue. Its administration significantly (P < 0.05) attenuated the oxidative stress in the heart tissue of aged rats through the counteraction of free radical formation by maintaining the enzymatic [glutathione peroxidase (GPx) and glutathione reductase (GR)] and non-enzymatic [reduced glutathione (GSH)] status at levels comparable to that of normal young rats. Our results conclude that dietary intake of chitosan restores the depleted myocardial antioxidant status and suggest that it could be an effective therapeutic agent in treatment of age-associated disorders where hypercholesterolemia and oxidative stress are the major causative factors.  相似文献   
30.
A socially-housed New Zealand white rabbit presented with a large subcutaneous mass on the ventral thorax approximately 11 mo after the intrahepatic delivery of a suspension of VX2 carcinoma cells to induce hepatocellular carcinoma as part of a nanoparticle study. The mass and closely associated axillary lymph node were removed en bloc. Immunohistochemical staining identified the mass as an undifferentiated carcinoma. The rabbit demonstrated no appreciable pathology at the study end point at 16 mo after VX2 inoculation. An additional rabbit from the same VX2 injection cohort was found at necropsy to have an unanticipated intraabdominal mass, also identified as an undifferentiated carcinoma. This case report summarizes the molecular analysis of both tumors through a novel PCR assay, which identified the delayed and aberrant onset of VX2 carcinoma in an extended timeframe not previously reported.Abbreviations: CRPV, cottontail rabbit papillomavirusThe VX2 squamous cell carcinoma cell line was developed in 1938 from cells isolated from a domestic rabbit with a Shope papillomavirus-induced skin papilloma.11,16 The inoculation of allogenic adult rabbits with the VX2 tumor cells results in a wholly anaplastic carcinoma that grows rapidly and forms frequent metastases.7,11 Molecular analysis of the VX2 carcinoma has revealed multiple integrated copies of highly methylated cottontail rabbit papilloma virus (CRPV) genomic material.5-7,17 For decades, the rabbit VX2 carcinoma has supported oncology research by providing a large animal model that supports the investigation of neoplasms of diverse tissues including liver, lung, pleural space, muscle, and bone.9,12,15,18,19 Benefits of this model include relatively simple inoculation, rapid growth with local tissue invasion, predictable metastases, and reproducibility.3,4,13,14 In the current report, we describe the use of VX2 cells intended to induce a hepatic carcinoma model in rabbits and the unexpected outcomes associated with the model.  相似文献   
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