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1.
Comparative DNA sequence studies between humans and nonhuman primates will be important for understanding the genetic basis of the phenotypic differences between these species. Here we compare approximately 27 Mb of human chromosome 21 with chimpanzee DNA sequences identifying 57 genomic rearrangements (deletions and insertions ranging in size from 0.2 to 8.0 kb) between the two species. These rearrangements are distributed along the entire length of chromosome 21, with approximately 35% found in genomic intervals encoding genes (genic intervals), and have occurred in the genomes of both humans and chimpanzees. Comparison of approximately 9 Mb of human chromosome 21 with orangutan, rhesus macaque, and woolly monkey DNA sequences identified a combined total of 114 genomic rearrangements between humans and nonhuman primates. Analysis of these rearrangements revealed that they are randomly distributed with respect to genic and nongenic intervals and identified one deletion that has likely resulted in the inactivation of a gene (beta1,3-galactosyltransferase) in the woolly monkey. Our data show that genomic rearrangements have occurred frequently during primate genome evolution and significantly contribute to the DNA differences between these species. These DNA rearrangements are commonly found in genic intervals, and thus provide natural starting points for focused investigations of qualitative and quantitative gene expression differences between humans and other primates.  相似文献   
2.
Somatic mitochondrial mutations are common in human cancers, and can be used as a tool for early detection of cancer. We have developed a mitochondrial Custom Reseq microarray as an array-based sequencing platform for rapid and high-throughput analysis of mitochondrial DNA. The MitoChip contains oligonucleotide probes synthesized using standard photolithography and solid-phase synthesis, and is able to sequence >29 kb of double-stranded DNA in a single assay. Both strands of the entire human mitochondrial coding sequence (15,451 bp) are arrayed on the MitoChip; both strands of an additional 12,935 bp (84% of coding DNA) are arrayed in duplicate. We used 300 ng of genomic DNA to amplify the mitochondrial coding sequence in three overlapping long PCR fragments. We then sequenced >2 million base pairs of mitochondrial DNA, and successfully assigned base calls at 96.0% of nucleotide positions. Replicate experiments demonstrated >99.99% reproducibility. In matched fluid samples (urine and pancreatic juice, respectively) obtained from five patients with bladder cancer and four with pancreatic cancer, the MitoChip detected at least one cancer-associated mitochondrial mutation in six (66%) of nine samples. The MitoChip is a high-throughput sequencing tool for the reliable identification of mitochondrial DNA mutations from primary tumors in clinical samples.  相似文献   
3.
To determine the auditory toxicity effects of long-term cis-dichlorodiammineplatinum II therapy, pure tone hearing thresholds were measured prior to therapy and repeated before each subsequent treatment. CDDP was given by a slow intravenous drip method at a low dose of 1 mg/kg body weight, with 37.5 gm mannitol, once a week for six treatments and every 3 weeks thereafter. From a group of 173 genitourinary cancer patients treated, 50 male patients were selected who received at least 12 months of CDDP with no active conductive ear pathology, and whose audiograms obtained at baseline, 6th weeks, 26th weeks, and 52nd weeks of treatment were all available for comparison. Pure tone threshold levels deteriorated across time particularly by the 52nd week and at the higher frequencies. Threshold differences across time were statistically significant and within a linear trend. Of the 50 cases, 30% showed suspect or no ototoxicity, 26% mild, 32% moderate, 2% marked, and 4% showed severe ototoxic changes. Of the two cases who developed severe ototoxicity, one showed complete recovery. There was partial recovery in 26% and no recovery in 54%. Individual variability in susceptibility to and recovery from ototoxicity necessitates systematic audiometric monitoring throughout the therapy.  相似文献   
4.
This review summarizes the history and current state of the known genetic basis for soybean resistance to Soybean mosaic virus (SMV), and examines how the integration of molecular markers has been utilized in breeding for crop improvement. SVM causes yield loss and seed quality reduction in soybean based on the SMV strain and the host genotype. Understanding the molecular underpinnings of SMV–soybean interactions and the genes conferring resistance to SMV has been a focus of intense research interest for decades. Soybean reactions are classified into three main responses: resistant, necrotic, or susceptible. Significant progress has been achieved that has greatly increased the understanding of soybean germplasm diversity, differential reactions to SMV strains, genotype–strain interactions, genes/alleles conferring specific reactions, and interactions among resistance genes and alleles. Many studies that aimed to uncover the physical position of resistance genes have been published in recent decades, collectively proposing different candidate genes. The studies on SMV resistance loci revealed that the resistance genes are mainly distributed on three chromosomes. Resistance has been pyramided in various combinations for durable resistance to SMV strains. The causative genes are still elusive despite early successes in identifying resistance alleles in soybean; however, a gene at the Rsv4 locus has been well validated.  相似文献   
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Background

The objective of this randomized, double-blind, placebo-controlled study was to evaluate the efficacy of sustained-release methylphenidate (MPH-SR) in treatment of methamphetamine dependence.

Methods

Fifty-six individuals who met DSM-IV-TR criteria for methamphetamine dependence participated in this 10-week trial. The participants were randomly allocated into two groups and received 18 to 54 mg/day sustained-released methylphenidate or placebo for 10 weeks. Craving was evaluated by a visual analogue craving scale every week. Urinary screening test for methamphetamine was carried out each week. The Beck Depression Inventory-II (BDI-II) was used to monitor participant depressive symptoms at baseline and bi-weekly during the treatment period.

Results

At the end of the trial, the MPH-SR group was less methamphetamine positive compared to the placebo group and the difference was significant (p = 0.03). By the end of the study, MPH-SR group showed significantly less craving scores compared to the placebo group [MD (95% CI) = -10.28(0.88-19.18), t(54) = 2.19, p = 0.03]. There was greater improvement in the depressive symptoms scores in the intervention group compared to the placebo group [MD (95% CI) =2.03(0.31-3.75), t (54) =2.37, p = 0.02].

Conclusion

Sustained-released methylphenidate was safe and well tolerated among active methamphetamine users and significantly reduced methamphetamine use, craving and depressive symptoms.

Trial registration

IRCT201202281556N38  相似文献   
7.

Background:

Cervical cancer is the most second common cancer among Iranian women. This study was carried out to compare the results of Pap smear method and Direct Visual Inspection (DVI) with 5% acetic acid in cervical cancer screening in Tabriz, Iran.

Material and Methods:

This cross-sectional study was carried out in Alzahra Therapeutic-Educational Centre, Tabriz, Iran in 2013 on 1000 women. First, Pap smear was done for all women, and then the cervix exposed with 5% acetic acid by cotton swab for 30 seconds and observed under adequate light. At the end, women with abnormal results in Pap smear or DVI method were referred to colposcopy and biopsy. Test''s sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), LR+, LR- and confidence interval (CI) were determined (P < 0.05).

Results:

Nine-hundred and seventy-four (94.7%) cases were normal and had no abnormal findings and 26 (2.6%) participants had positive results in Pap smear or DVI test. Twelve women had abnormal Pap smear (nine women with atypical squamous cells of undetermined significance, ASCUS, three women with dysplasia, atypical endocervical, and low-grade squamous intraepithelial lesion, LSIL results) and 14 women had positive DVI (four women with human papillomavirus, HPV or koilocyte,) and one women with abnormality in both method had carcinoma in biopsy that referred to oncologist. In this study the sensitivity, specificity, PPV and NPV for DVI were 71.4%, 50%, 35.7%, and 81.8% respectively in comparison with 14.3%, 50%, 10%, and 60% for Pap smear.

Conclusion:

As the DVI method has higher sensitivity and positive predictive value than Pap smear, it could be used as a useful method beside the Pap smear.  相似文献   
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Texture modification of foods to a pureed consistency is a common management approach for older adults with dysphagia. Long-term care (LTC) facilities commonly produce some pureed food in-house. This study investigated challenges and preferred practices associated with the production of pureed food in LTC facilities. Nutrition Managers (n = 27) and cooks (n = 26) from 25 Ontario LTC facilities were recruited for one-on-one, semistructured interviews. Interviews were digitally recorded, transcribed, and analyzed using inductive thematic analysis. Four themes arose from the data to exemplify challenges in production, including (a) difficulty in using standardized recipes, (b) varied interpretation of governmental guidelines, (c) lack of consistency in terminology and texture, and (d) wanting to improve the visual appeal. These challenges were reported to reduce the quality of in-house produced pureed food. Preferred practices to overcome these challenges were also provided by participants, such as involving cooks in pureed recipe improvements and tailoring to the specific needs of residents. Incorporation of these practices into pureed food production may help to shape and improve future practice and pureed food products.  相似文献   
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