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981.
Bahman Shams Esfandabad Mahmoud Karami Mahmoud-Reza Hemami Borhan Riazi Mohammad-Bagher Sadough 《European Journal of Wildlife Research》2010,56(6):883-894
Wild goat (Capra aegagrus) is one of the highly valued but threatened ungulates of Iran. Seasonal habitat use of wild goat was studied from October
2006 to September 2008 in Haftad Gholleh Protected Area, central Iran. We developed averaged logistic regression models based
on Akaike Information Criterion weights for each season. The obtained habitat suitability models showed high sensitivity (greater
than 88%) for all evaluation datasets. Wild goat habitat use was positively related with steep slopes, areas near rocky substrates
and water sources, west-facing slopes and areas far from roads in all seasons. Core zones of protected area covered nearly
70% of suitable habitats for wild goats, predicted by logistic regression models. Northern core zone covered more than 61%
of predicted suitable habitats, which should receive more attention in management actions. The southern core zone boundaries
should be considered to increase the encompassed suitable habitats. There was a substantial overlap between seasonal suitable
habitats with the highest overlap observed between spring and summer and summer and fall. 相似文献
982.
Sampada B. Upadhye Swapnil J. Kulkarni Soumyajit Majumdar Mitchell A. Avery Waseem Gul Mahmoud A. ElSohly Michael A. Repka 《AAPS PharmSciTech》2010,11(2):509-517
Δ9-Tetrahydrocannabinol hemisuccinate (THC-HS), an ester prodrug of Δ9-tetrahydrocannabinol (THC) has been investigated for its potential to form inclusion complexes with modified synthetic beta-cyclodextrins
(CDs). Phase solubility studies were performed to determine the stoichiometric ratio of complexation of THC-HS with random
methylated beta-cyclodextrin (RAMEB) and 2-hydroxypropyl beta-cyclodextrin (HPBCD). THC-HS/RAMEB and THC-HS/HPBCD solid systems
were prepared by lyophilization and the lyophilized complexes were characterized by Fourier transform infrared (FT-IR) spectroscopy,
proton nuclear magnetic spectroscopy, and molecular modeling techniques. The formation of inclusion complexes of THC-HS/RAMEB
and THC-HS/HPBCD was demonstrated by an AL type curve with the slopes less than unity by the phase solubility method. The association constants for THC-HS/RAMEB and
THC-HS/HPBCD were found to be 562.48 and 238.83 M−1, respectively. The stoichiometry of both of the complexes was found to be 1:1 as determined from the Job's plot. This was
confirmed by 1H NMR and FT-IR techniques. The results obtained from the molecular modeling studies were in accordance with the data obtained
from nuclear magnetic resonance and FT-IR. The docking studies revealed the most probable mode of binding of THC-HS with RAMEB
in which the alkyl chain was submerged in the hydrophobic pocket of the CD molecule and hydrogen bonding interactions were
observed between the hemisuccinate ester side chain of THC-HS and the rim hydroxy groups of RAMEB. The solubility of THC-HS
was significantly higher in RAMEB compared to HPBCD. Solid dispersions of THC-HS with CDs will be further utilized to develop
oral formulations of THC-HS with enhanced bioavailability. 相似文献
983.
Mahmoud A. Ghannoum Richard J. Jurevic Pranab K. Mukherjee Fan Cui Masoumeh Sikaroodi Ammar Naqvi Patrick M. Gillevet 《PLoS pathogens》2010,6(1)
The oral microbiome–organisms residing in the oral cavity and their collective genome–are critical components of health and disease. The fungal component of the oral microbiota has not been characterized. In this study, we used a novel multitag pyrosequencing approach to characterize fungi present in the oral cavity of 20 healthy individuals, using the pan-fungal internal transcribed spacer (ITS) primers. Our results revealed the “basal” oral mycobiome profile of the enrolled individuals, and showed that across all the samples studied, the oral cavity contained 74 culturable and 11 non-culturable fungal genera. Among these genera, 39 were present in only one person, 16 genera were present in two participants, and 5 genera were present in three people, while 15 genera (including non-culturable organisms) were present in ≥4 (20%) participants. Candida species were the most frequent (isolated from 75% of participants), followed by Cladosporium (65%), Aureobasidium, Saccharomycetales (50% for both), Aspergillus (35%), Fusarium (30%), and Cryptococcus (20%). Four of these predominant genera are known to be pathogenic in humans. The low-abundance genera may represent environmental fungi present in the oral cavity and could simply be spores inhaled from the air or material ingested with food. Among the culturable genera, 61 were represented by one species each, while 13 genera comprised between 2 and 6 different species; the total number of species identified were 101. The number of species in the oral cavity of each individual ranged between 9 and 23. Principal component (PCO) analysis of the obtained data set followed by sample clustering and UniFrac analysis revealed that White males and Asian males clustered differently from each other, whereas both Asian and White females clustered together. This is the first study that identified the “basal mycobiome” of healthy individuals, and provides the basis for a detailed characterization of the oral mycobiome in health and disease. 相似文献
984.
Saad Zaky Hebat-Allah Rashed Ehab Faouzy Mahmoud Rezk Abdelwahed Hussein 《Cellular immunology》2010,265(2):97-104
The aim of this study was to determine the clinicopathologic features and Hepatitis B virus genotypes in HBV-infected patients in the Upper Egypt. Eighty-three HBsAg-positive patients (28 carriers, 14 with chronic hepatitis, 32 with liver cirrhosis and 9 with hepatocellular carcinoma) were enrolled. Blood was collected and serum samples obtained were screened for Hepatitis markers genotyping was conducted for 6 HBV genotypes (A through F) using a method for genotyping HBV by primer specific polymerase chain reaction. Genotype D was the only genotype detected in different clinical forms of chronic HBV infection (carriers, chronic hepatitis, cirrhosis and hepatocellular carcinoma) and, in all patients who had elevated or normal alanine aminotransferase levels and in all ages. HBeAg was absent in 78 patients suggesting the presence of pre-core or core mutations. Positive correlation was found among serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), histological activity index and grade of hepatitis. This study provides the first indication about the clinicopathologic features of HBV-infected patients in the Upper Egypt. It also reports the predominance of genotype D in this region. 相似文献
985.
Oikonomopoulou K Hansen KK Saifeddine M Vergnolle N Tea I Diamandis EP Hollenberg MD 《Biological chemistry》2006,387(6):677-685
Serine proteinases, like trypsin, can play a hormone-like role by triggering signal transduction pathways in target cells. In many respects these hormone-like actions of proteinases can now be understood in terms of the pharmacodynamics of the G protein-coupled 'receptor' responsible for the cellular actions of thrombin (proteinase-activated receptor-1, or PAR1). PAR1, like the other three members of this receptor family (PAR2, PAR3 and PAR4), has a unique mechanism of activation involving the proteolytic unmasking of an N-terminally tethered sequence that can activate the receptor. The selective activation of each PAR by short synthetic peptides representing these sequences has demonstrated that PAR1, PAR2 and PAR4 play important roles in regulating physiological responses ranging from vasoregulation and cell growth to inflammation and nociception. We hypothesise that the tissue kallikreins may regulate signal transduction via the PARs. Although PARs can account for many of their biological actions, kallikreins may also cause effects by mechanisms not involving the PARs. For instance, trypsin activates the insulin receptor and thrombin can act via a mechanism involving its non-catalytic domains. Based on the data we summarise, we propose that the kallikreins, like thrombin and trypsin, must now be considered as important 'hormonal' regulators of tissue function. 相似文献
986.
Arylsulfatase B (ASB) hydrolyzes the desulfation of N-acetylgalactosamine-4-sulfate at the non-reducing terminal of glycosaminoglycans. This enzyme activity was found to be elevated in mice schistosomiasis. In the present study, the catalytic and immunological properties of purified ASB from the liver of Schistosoma-infected mouse was investigated in the presence and absence of the schistosomicidal drugs praziquantel and Commiphora extract. The in vitro effect of praziquantel was found to be inhibitory with a Ki value of 5.5 x 10(-4) M while that of commiphora extract was as an activator. Furthermore, these drugs did not have an observed effect on the immunological properties of ASB with regard to its binding to its polyclonal rabbit antibody. These results indicate that some schistosomicidal drugs may reverse the alteration of the catalytic properties of the enzyme in schistosomiasis. 相似文献
987.
A protein positive charge near the flavin N(1) locus is a distinguishing feature of most flavoprotein oxidases, with mechanistic implications for the modulation of flavin reactivity. A recent study showed that in the active site of choline oxidase the protein positive charge is provided by His(466). Here, we have reversed the charge by substitution with aspartate (CHO-H466D) and, for the first time, characterized a flavoprotein oxidase with a negative charge near the flavin N(1) locus. CHO-H466D formed a stable complex with choline but lost the ability to oxidize the substrate. In contrast to the wild-type enzyme, which binds FAD covalently in a 1:1 ratio, CHO-H466D contained approximately 0.3 FAD per protein, of which 75% was not covalently bound to the enzyme. Anaerobic reduction of CHO-H466D resulted in the formation of a neutral hydroquinone, with no stabilization of the flavin semiquinone; in contrast, the anionic semiquinone and hydroquinone species were observed with the wild type and a H466A variant of the enzyme. The midpoint reduction potential for the oxidized-reduced couple in CHO-H466D was approximately 160 mV lower than that of the wild-type enzyme. Finally, CHO-H466D lost the ability to form complexes with glycine betaine or sulfite. Thus, with a reversal of the protein charge near the FAD N(1) locus, choline oxidase lost the ability to stabilize negative charges in the active site, irrespective of whether they develop on the flavin or are borne on ligands, resulting in defective flavinylation of the protein, the decreased electrophilicity of the flavin, and the consequent loss of catalytic activity. 相似文献
988.
Nassar MI 《Carbohydrate research》2006,341(1):160-163
Two new apigenin triglycosides, apigenin 6-C-[beta-D-xylopyranosyl-(1'-->2')-beta-D-galactopyranoside]-7-O-beta-D-glucopyranoside and apigenin 6-C-[beta-D-xylopyranosyl-(1'-->2')-beta-D-galactopyranoside]-7-O-beta-D-(6-O-p-coumarylglucopyranoside) were isolated from the ethanol extract of the seeds of Syzygium aromaticum. Their structures were elucidated by chemical and spectral analysis (UV, FABMS, 1H, 13C NMR, HMQC, HMBC, NOESY and DEPT). 相似文献
989.
Extracellular pathogenesis-related proteins, including glucanases, are expressed at cold temperatures in winter rye (Secale cereale) and display antifreeze activity. We have characterized recombinant cold-induced glucanases from winter rye to further examine their roles and contributions to cold tolerance. Both basic beta-1,3-glucanases and an acidic beta-1,3;1,4-glucanase were expressed in Escherichia coli, purified, and assayed for their hydrolytic and antifreeze activities in vitro. All were found to be cold active and to retain partial hydrolytic activity at subzero temperatures (e.g. 14%-35% at -4 degrees C). The two types of glucanases had antifreeze activity as measured by their ability to modify the growth of ice crystals. Structural models for the winter rye beta-1,3-glucanases were developed on which putative ice-binding surfaces (IBSs) were identified. Residues on the putative IBSs were charge conserved for each of the expressed glucanases, with the exception of one beta-1,3-glucanase recovered from nonacclimated winter rye in which a charged amino acid was present on the putative IBS. This protein also had a reduced antifreeze activity relative to the other expressed glucanases. These results support the hypothesis that winter rye glucanases have evolved to inhibit the formation of large, potentially fatal ice crystals, in addition to having enzymatic activity with a potential role in resisting infection by psychrophilic pathogens. Glucanases of winter rye provide an interesting example of protein evolution and adaptation aimed to combat cold and freezing conditions. 相似文献
990.
Pituitary glands were removed from sexually mature female turtles (Chrysemys picta) and they were injected intraperitoneally (i.p.) into other mature females of the same species (experimental). In addition mature females of the same species received saline injection only (controls). Initially all the turtles used in this study were steroidogenically inactive with corpora lutea already undergoing luteolysis (degeneration) as these turtles had ovioposited their eggs approximately 2 weeks earlier. Forty-eight hour post injection the corpora lutea were removed from the control and experimental turtles. In the experimental turtles, the lutein granulosa cells developed ultrastructural features such as tubular and cisternal smooth endoplasmic reticulum (SER) and mitochondria with tubular cristae associated with lipid droplets. However, the controls maintained degenerative corpora lutea without steroidogenic ultrastructural features. The circulating progesterone (Pro) levels in the experimental turtles were significantly higher than the controls (P<0.049). Although the 48h development of steroidogenic ultrastructural features in the lutein granulosa cells was only partial in development, the effect of the pituitary taken from the inactive donor triggered an activating process within a short period, clear evidence of gonadotropic effect on the inactive corpora lutea. The present data offer interesting information on the short-term effect of gonadotropins during the non-reproductive period. This information may have useful implication under natural conditions particularly during the onset of a new reproductive cycle where the ovary is still inactive. 相似文献