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81.
82.
Mass spectrometric identification of proteins in species lacking validated sequence information is a major problem in veterinary science. In the present study, we used ochratoxin A producing Penicillium verrucosum to identify and quantitatively analyze proteins of an organism with yet no protein information available. The work presented here aimed to provide a comprehensive protein identification of P. verrucosum using shotgun proteomics. We were able to identify 3631 proteins in an “ab initio” translated database from DNA sequences of P. verrucosum. Additionally, a sequential window acquisition of all theoretical fragment‐ion spectra analysis was done to find differentially regulated proteins at two different time points of the growth curve. We compared the proteins at the beginning (day 3) and at the end of the log phase (day 12).  相似文献   
83.
A three-component reaction of an isocyanide, a dialkyl acetylenedicarboxylate, and tetronic acid in dichloromethane at room temperature afforded 4H-furo[3,4-b]pyran derivatives. These compounds are closely related with ring systems, TAN-2483B, TAN-2483A, and FD-211 which have a broad spectrum of biological activity.  相似文献   
84.
Amplified fragment length polymorphism (AFLP) markers were used to assess the genetic diversity of 57 Achillea accessions belonging to five species, A. millefolium, A. filipendulina, A. tenuifolia, A. santolina and A. biebersteinii. Nine AFLP primer combinations were used, which produced 301 polymorphic bands. In most species, a high level of genetic variation was detected among the genotypes. The Jaccard's similarity indices (J), based on AFLP profiles, were subjected to UPGMA cluster analysis. Application of Mantel's test for cophenetic correlation to the cluster analysis indicated the high fitness of the accessions to a group (r = 0.918). The dendrogram generated revealed five major groups corresponding to five species. The principle coordinate analysis (PCoA) data confirmed the results of the clustering. Among the species, A. teunifolia and A. santolina showed the greatest and the least genetic diversity, respectively. A. filipendulina accessions were acquired primarily from the same ecological regions of western Iran. Accessions belonging to A. biebersteinii originated from the Isfahan province and were separated from other species at the root of the dendrogram. The results of the clustering method, based on AFLP markers, corresponded closely with the geographical origins of the genotypes. The results of the present study could contribute to a better understanding and management of conservation and exploitation of the Achillea germplasm.  相似文献   
85.

Background

Lung cancer remains the leading cause of cancer-related deaths worldwide. The recurrence rate ranges from 35–50% among early stage non-small cell lung cancer patients. To date, there is no fully-validated and clinically applied prognostic gene signature for personalized treatment.

Methodology/Principal Findings

From genome-wide mRNA expression profiles generated on 256 lung adenocarcinoma patients, a 12-gene signature was identified using combinatorial gene selection methods, and a risk score algorithm was developed with Naïve Bayes. The 12-gene model generates significant patient stratification in the training cohort HLM & UM (n = 256; log-rank P = 6.96e-7) and two independent validation sets, MSK (n = 104; log-rank P = 9.88e-4) and DFCI (n = 82; log-rank P = 2.57e-4), using Kaplan-Meier analyses. This gene signature also stratifies stage I and IB lung adenocarcinoma patients into two distinct survival groups (log-rank P<0.04). The 12-gene risk score is more significant (hazard ratio = 4.19, 95% CI: [2.08, 8.46]) than other commonly used clinical factors except tumor stage (III vs. I) in multivariate Cox analyses. The 12-gene model is more accurate than previously published lung cancer gene signatures on the same datasets. Furthermore, this signature accurately predicts chemoresistance/chemosensitivity to Cisplatin, Carboplatin, Paclitaxel, Etoposide, Erlotinib, and Gefitinib in NCI-60 cancer cell lines (P<0.017). The identified 12 genes exhibit curated interactions with major lung cancer signaling hallmarks in functional pathway analysis. The expression patterns of the signature genes have been confirmed in RT-PCR analyses of independent tumor samples.

Conclusions/Significance

The results demonstrate the clinical utility of the identified gene signature in prognostic categorization. With this 12-gene risk score algorithm, early stage patients at high risk for tumor recurrence could be identified for adjuvant chemotherapy; whereas stage I and II patients at low risk could be spared the toxic side effects of chemotherapeutic drugs.  相似文献   
86.
We examined the possible relationship between three RAGE polymorphisms, ?429C/T, ?374 T/A, and 63-bp deletion, and susceptibility to childhood acute lymphoblastic leukemia (ALL) in an Iranian population. This study included 75 ALL patients and 115 healthy subjects. Genotyping was performed using HEXA-ARMS-polymerase chain reaction. We found no significant association among RAGE gene polymorphisms and the risk for ALL at genotype, allelic and haplotype levels (P > 0.05). The hemoglobin levels were higher in patients with RAGE ?374 TT than in the TA carriers (P = 0.019). Our results demonstrated that the RAGE gene variations were not associated with risk of pediatrics ALL.  相似文献   
87.
This study was performed to investigate trace elements and arsenic contents among Sudanese inhabitants living in the north, east, and west of Sudan. Inductively coupled plasma atomic emission spectrometry was used to determine the contents of Zn and Cu. Graphite furnace atomic absorption spectrometry was used to determine Se in serum samples. It was found that Se and Cu are in the normal range. Zinc showed discrepancies among all studied groups. Acute Zn deficiency was detected in the northern and eastern regions of Sudan. Inductively coupled plasma mass spectroscopy was operated in the dynamic reaction cell mode to determine the arsenic content in the nail samples of the northern inhabitants of Sudan. High values of arsenic were found in the northern people compared with the control group. This elevation could be linked to the misuse of insecticides and herbicides which might be associated with the high rate of cancer incidence in this region.  相似文献   
88.
The protective immune response against Brucella involves T‐cell‐mediated immunity. T‐lymphocyte receptors, CD28 and cytotoxic T‐lymphocyte‐associated protein‐4 (CTLA‐4), bind the same ligands, CD80 (B7‐1) and CD86 (B7‐2) on antigen‐presenting cells and regulate T cell activation. CD28 delivers stimulatory signals whereas CTLA‐4 provides inhibitory signals for T cell activation. Here, we investigated the association of four polymorphisms in CTLA4 (+49A/G [rs231775] and ?318 C/T [rs5742909]) and its ligand CD86 (+1057 G/A [rs1129055] and +2379G/C [rs17281995]) with brucellosis infection. The study included 153 Iranian patients with active brucellosis and 128 healthy individuals as the control group. Genotyping of the CTLA4 and CD86 variants was performed using tetra amplification refractory mutation system‐polymerase chain reaction (T‐ARMS‐PCR) and PCR–restriction fragment length polymorphism analysis, respectively. It was found that the CTLA4 ?318 CT genotype and T allele were present more frequently in cases than in controls and are therefore associated with an increased risk for brucellosis (?318 TT genotype; OR = 2.544, P = 0.002). Likewise, the CD86 +1057 GA and AA genotypes and A allele were associated with an increased risk of brucellosis (+1057 AA genotype; OR = 3.81, P = 0.001). However, no statistically significant difference between brucellosis patients and controls in the allele and genotype distributions of CTLA4, +49A/G (P = 0.859) and CD86, +2379G/C (P = 0.476) was found. In conclusion, CTLA4 ?318 CT genotype and T allele and the CD86 +057 GA and AA genotypes and A allele play roles as risk factors for developing brucellosis infection in Iran.
  相似文献   
89.
Genome-wide association studies (GWAS) have been instrumental in identifying novel genetic variants associated with altered plasma lipid levels. However, these quantitative trait loci have not been tested in the Indian population, where there is a poorly understood and growing burden of cardiometabolic disorders. We present the association of six single nucleotide polymorphisms in 1671 sib pairs (3342 subjects) with four lipid traits: total cholesterol, triglycerides, high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C). We also investigated the interaction effects of gender, location, fat intake and physical activity. Each copy of the risk allele of rs964184 at APOA1 was associated with 1.06 mmol/l increase in triglycerides (SE = 0.049; p = 0.006), rs3764261 at CETP with 1.02 mmol/l increase in both total cholesterol (SE = 0.042; p = 0.017) and HDL-C (SE = 0.041; p = 0.008), rs646776 at CELSR2-PSRC1-SORT1 with 0.96 mmol/l decrease in cholesterol (SE = 0.043; p = 0.0003) and 0.15 mmol/l decrease in LDL-C levels (SE = 0.043; p = 0.0003) and rs2954029 at TRIB1 with 1.02 mmol/l increase in HDL-C (SE = 0.039; p = 0.047). A combined risk score of APOA1 and CETP loci predicted an increase of 1.25 mmol/l in HDL-C level (SE = 0.312; p = 0.0007). Urban location and sex had strong interaction effects on the genetic association of most of the studied loci with lipid traits. To conclude, we validated four genetic variants (identified by GWAS in western populations) associated with lipid traits in the Indian population. The interaction effects found here may explain the sex-specific differences in lipid levels and their heritability. Urbanization appears to influence the nature of the association with GWAS lipid loci in this population. However, these findings will require replication in other Indian populations.  相似文献   
90.
Treatment of Cutaneous leishmaniasis (CL) is based on using antimoniate derivatives; patients’ compliance for systemic injections is low due to the pain and systemic complications. In this randomized open trial, the efficacy of intra-lesional (IL) injections of meglumine antimoniate (MA) once a week vs. twice a week in the treatment of Anthrpoponothic CL caused by L. tropica was studied. Eligible volunteer patients were selected according to inclusion/exclusion criteria. The included patients were randomly allocated to receive IL-MA injections once a week or twice a week. The primary outcome was set as complete healing of the lesion(s), and defined as complete re-epithelialization and absence of induration in the lesions. A total of 180 parasitologicaly proven CL patients caused by L. tropica were recruited, 90 patients were treated with weekly IL-MA and 90 patients received IL-MA twice a week. The complete cure was 87.9% vs. 89.2% in the group received weekly and twice a week IL-MA injections, respectively (P = 0.808). Patients’ compliance was acceptable and side effects were limited to a few local allergic reactions to MA. Median time to healing was significantly shorter in patients who received IL-MA twice a week (median ± SE) 37±3.8, (CI: 29.6–44.4) days compared to whom received IL-MA once a week 60±2.3, (CI: 55.6–64.5) days (P< 0.001), however the number of injections was higher in group who received IL-MA twice a week (12 vs. 9 injections). In conclusion, the rate of cure in the group of CL patients with IL-MA twice a week was not significantly different from the group who received IL-MA once a week shorten, but the duration of healing was shorter in the group who received IL-MA twice a week while the group received more injections so is recommended to use IL-MA once a week due to the fact the compliance is acceptable with limited side effects.Clinical Trial Registration: IRCT20081130001475N13; https://en.irct.ir/.  相似文献   
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