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Procedures for performing cladistic analyses can provide powerful tools for understanding the evolution of neuropeptide and polypeptide hormone coding genes. These analyses can be done on either amino acid data sets or nucleotide data sets and can utilize several different algorithms that are dependent on distinct sets of operating assumptions and constraints. In some cases, the results of these analyses can be used to gauge phylogenetic relationships between taxa. Selecting the proper cladistic analysis strategy is dependent on the taxonomic level of analysis and the rate of evolution within the orthologous genes being evaluated. For example, previous studies have shown that the amino acid sequence of proopiomelanocortin (POMC), the common precursor for the melanocortins and beta-endorphin, can be used to resolve phylogenetic relationships at the class and order level. This study tested the hypothesis that POMC sequences could be used to resolve phylogenetic relationships at the family taxonomic level. Cladistic analyses were performed on amphibian POMC sequences characterized from the marine toad, Bufo marinus (family Bufonidae; this study), the spadefoot toad, Spea multiplicatus (family Pelobatidae), the African clawed frog, Xenopus laevis (family Pipidae) and the laughing frog, Rana ridibunda (family Ranidae). In these analyses the sequence of Australian lungfish POMC was used as the outgroup. The analyses were done at the amino acid level using the maximum parsimony algorithm and at the nucleotide level using the maximum likelihood algorithm. For the anuran POMC genes, analysis at the nucleotide level using the maximum likelihood algorithm generated a cladogram with higher bootstrap values than the maximum parsimony analysis of the POMC amino acid data set. For anuran POMC sequences, analysis of nucleotide sequences using the maximum likelihood algorithm would appear to be the preferred strategy for resolving phylogenetic relationships at the family taxonomic level.  相似文献   
2.
Thousands of people were infected with Vibrio cholerae during the outbreak in Iraq in 2007-2009. Vibrio cholerae was shown to be variable in its content of virulence determinants and in its antibiotic sensitivity. This study was designed to isolate and characterize clinical and environmental V.?cholerae isolates and to determine antibiotic sensitivity, enzyme and toxin production, and the presence of virulence genes. Eighty clinical and five environmental bacterial isolates were collected and diagnosed by subjecting them to microscopic, biochemical, serological, and molecular analysis. The results revealed that 55% of clinical isolates belonged to the Inaba serotype, 32.5% to the Ogawa serotypes, and 12.5% to the Non-O1 serotype. All environmental V.?cholerae isolates belonged to the Non-O1 serotype. All environmental isolates were sensitive to all examined antimicrobial agents, while all clinical isolates showed a high sensitivity (100%) to ampicillin, gentamicin, cephalothin, tetracycline, erythromycin, and ciprofloxacin, and a high resistance (97.5%) to co-trimoxazole, nalidixic acid, and chloramphenicol. It was found that all V.?cholerae (O1) isolates were resistant to the Vibrio static O129 and all Non-O1 V.?cholerae isolates were sensitive to the Vibrio static O129. All clinical and environmental isolates produced hemolysin (100%) and lecithinase (100%), while they showed various production rates of protease (90% of clinical and 60% of environmental) and lipase (50% of clinical and 20% of environmental). The ompW gene was amplified in all the clinical and environmental V.?cholerae isolates, but not in other related and nonrelated bacteria. Multiplex PCR analysis showed that the toxR gene was amplified in all clinical and environmental isolates, while ctxA, ctxB, tcpA genes were amplified only in clinical (O1) isolates. This study indicates the differences in the production of some enzymes and toxins and in the content of virulence genes between clinical and environmental isolates in Iraq during the outbreak (2007-2009).  相似文献   
3.
MethodsThis cross-sectional cohort study was conducted to identify LOMS and YOMS patients’ with relapsing remitting course at MS diagnosis. Time (years) to reach sustained EDSS 6.0 was compared between LOMS and AOMS patients. Cox proportional hazards model was used to evaluate the demographic and clinical predictors of time to EDSS 6.0 in these cohorts.ResultsLOMS and YOMS cohorts comprised 99 (10.7%) and 804 (89.3%) patients respectively. Spinal cord presentation at MS onset was more common among LOMS patients (46.5% vs. 32.3%). The proportions of LOMS and YOMS patients reaching EDSS 6.0 during the follow-up period were 19.2% and 15.7% respectively. In multivariable Cox proportional hazards model, older age at MS onset (adjusted hazard ratio (aHR) = 3.96; 95% CI: 2.14–7.32; p < 0.001), male gender (aHR = 1.85; 95% CI: 1.22–2.81; p = 0.004) and spinal cord presentation at onset (aHR = 1.47; 95% CI: 0.98–2.21; p = 0.062) were significantly associated with shorter time to EDSS 6.0.ConclusionsLOMS patients attained EDSS 6.0 in a significantly shorter period that was influenced by male gender and spinal cord presentation at MS onset.  相似文献   
4.
A signature feature of tetrapod pro-opiomelanocortin (POMC) is the presence of three melantropin (MSH) coding regions (α-MSH, β-MSH, γ-MSH). The MSH duplication events occurred early during the radiation of the jawed vertebrates well over 400 million years ago. However, in at least one order of modern bony fish (subdivision Teleostei; order Salmoniformes; i.e. salmon and trout) the γ-MSH sequence has been deleted from POMC. To determine whether the γ-MSH deletion has occurred in other teleost orders, a POMC cDNA was cloned from the pituitary of the neoteleost Oreochromis mossambicus (order Perciformes). In O. mossambicus POMC, the deletion is more extensive and includes the γ-MSH sequence and most of the joining peptide region. Because the salmoniform and perciform teleosts do not share a direct common ancestor, the γ-MSH deletion event must have occurred early in the evolution of the neoteleost fishes. The post-translational processing of O. mossambicus POMC occurs despite the fact that the proteolytic recognition sequence, (R/K)-Xn-(R/K) where n can be 0, 2, 4, or 6, a common feature in mammalian neuropeptide and polypeptide hormone precursors, is not present at several cleavage sites in O. mossambicus POMC. These observations would indicate that either the prohormone convertases in teleost fish use distinct recognition sequences or vertebrate prohormone convertases are capable of recognizing a greater number of primary sequence motifs around proteolytic cleavage sites.  相似文献   
5.
Abstract The oxidation of bicyclo[3.2.0]hept-2-en-6-one and 7- endo propylbicyclo[3.2.0]hept-2-en-one was investigated using whole cells of Pseudomonas putida NCIMB 10007 and Xanthobacter autotrophicus NCIMB 10811. The bacteria demonstrated both regio- and enantioselective oxidation of the substrates. P. putida gave 'mirror image' with both substrates when the products of these oxidations were compared with cells grown on the different enantiomers of camphor. The regio- and enantioselectivity of the oxidation of the substrates by X. autotrophicus were enhanced by the 7- endo propyl substitution of bicyclo[3.2.0]hept-2-en-6-one.  相似文献   
6.
The purpose of the present study is to evaluate the sensitivity of Candida species isolated from oral candidiasis and diaper dermatitis infections in children. The children referring to private and public clinics in Ilam, Iran were exmined for oral candidiasis and diaper dermatitis. In this study, 248 oral candidiasis and diaper dermatitis samples were collected and cultured.Candida species were identified by using standard methods. Resistance and sensitivity to amphotericin B, nystatin, ketoconazole, fluconazole, itraconazole, clotrimazole, and posaconazole were determined using the CLSI M44-A standard disk diffusion method. From the 248 studied samples, 149 were positive for Candida, among which the Candida albicans was the most prevalent (64.4%). The resistance of different Candida species to nystatin, itraconazole, fluconazole, ketoconazole, clotrimazole, voriconazole, and posaconazole were 4, 43, 34.2, 34.9, 21.5, 6, and 6.7%, respectively. No resistance to amphotericin B was observed. Considering rather low resistance to nystatin, this drug is the best choice for oral candidiasis and diaper dermatitis.  相似文献   
7.
An 8-week study was conducted to evaluate three different diets supplemented with bovine lactoferrin (LF) at 0 (control), 800, and 1200 mg LF kg?1 diet on somatic growth, hemato-immunological parameters, antioxidant status, and digestive enzyme activities in silvery-black porgy (Sparidentex hasta) juveniles. Fish fed the 800 mg LF kg?1 diet had higher growth performance and feed utilization parameters than the other groups. Hematological and liver antioxidant parameters were not affected by dietary LF supplementation. Fish fed the 800 mg LF kg?1 diet had higher plasma lysozyme activity values than the other groups. Total protease activity was higher in fish fed LF-supplemented diets than the control group. Results indicated that diet supplemented with 800 mg kg?1 for 8 weeks enhanced somatic growth performance, lysozyme activity, and proteolytic digestive enzyme activities in S. hasta, as well as improving feed efficiency parameters like the protein efficiency and feed conversion ratios.  相似文献   
8.
The aim of this study was to assess the cytotoxic effects of various concentrations of miltefosine on Leishmania major (MRHO/IR/75/ER) and L. tropica (MHOM/IR/02/Mash10) promastigotes and to observe the programmed cell death features. The colorimetric MTT assay was used to find L. major and L. tropica viability and the obtained results were expressed as 50% inhibitory concentration (IC50). Also, 50% effective doses (ED50) for L. major and L. tropica amastigotes were also determined. Annexin-V FLUOS staining was performed to study the cell death properties of miltefosine using FACS analysis. Qualitative analysis of the total genomic DNA fragmentation was performed by agarose gel electrophoresis. Furthermore, to observe changes in cell morphology, promastigotes were examined using light microscopy. In both strains of L. major and L. tropica, miltefosine induced dose-dependent death with features of apoptosis, including cell shrinkage, DNA laddering, and externalization of phosphatidylserine. The IC50 was achieved at 22 μM and 11 μM for L. major and L. tropica after 48 hr of incubation, respectively. ED50 of L. major and L. tropica amastigotes were 5.7 μM and 4.2 μM, respectively. Our results indicate that miltefosine induces apoptosis of the causative agent of cutaneous leishmaniasis in a dose-dependent manner. Interestingly, L. major did not display any apoptotic changes when it was exposed to miltefosine in concentrations sufficient to kill L. tropica.  相似文献   
9.
Vaginal Candidiasis is the most common and important opportunistic fungal infection in women. By increasing use of antifungal drugs in recent years, it has caused drug resistance. This study aims to evaluate antifungal drugs susceptibility of Candida. spp isolated of women with vaginitis from Ilam-Iran during 2013-2014. samples were collected and cultured from 385 women with vaginitis, then Candida.spp was diagnosed by standard method. Antifungal drug susceptibility test for nystatin 100 unit/disk, fluconazole 10µg/disk, itraconazole 10µg/disk, ketoconazole 10µg/disk, amphotericinB 20µg/disk, clotrimazole 10µg/disk, posaconazole 5µg/disk, and voriconazole 1µg/disk were carried out by M44-A method(CLSI). From all culture positive samples, 150 isolates were Candida albicans and 89 isolates were non-albicans. The resistance to fluconazole, itraconazole, ketoconazole, clotrimazole, voriconazole, posaconazole, nystatin and amphotericin B was 76%, 62%, 72%, 55%, 6%, 7%, 1% and 0%. The highest resistance was seen for fluconazole , itraconazole, and the highest susceptible was seen for nystatin and amphotericin B. These results indicate nystatin and amphotericin B can be used as the first line for empirical therapy of vaginal candidiasis in the district.  相似文献   
10.
The detection of the prodynorphin gene in anuran amphibians and lungfishes may indicate that this gene arose as a result of the duplication of the proenkephalin gene early during the divergence of the Sarcopterygii, or that this gene may predate the divergence of the ray-finned fish and the lobe-finned fish. The cloning of prodynorphin-related genes from the pufferfish and zebrafish supports the latter hypothesis. This study analyzes trends in the radiation of the prodynorphin gene in teleosts. Prodynorphin cDNAs were cloned from the brain of the eel Anguilla rostrata and the Nile tilapia, Oreochromis niloticus. These teleost prodynorphin sequences have distinct alpha-neoendorphin, dynorphin A, and dynorphin B sequences, and a novel opioid sequence, YGGFI. The relationship of these teleost prodynorphin sequences to other actinopterygian and sarcopterygian prodynorphin sequences will be discussed.  相似文献   
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