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171.
172.
The extent of genetic variation found in drug metabolism genes and its contribution to interindividual variation in response to medication remains incompletely understood. To better determine the identity and frequency of variation in 11 phase I drug metabolism genes, the exons and flanking intronic regions of the cytochrome P450 (CYP) isoenzyme genes CYP1A1, CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4 and CYP3A5 were amplified from genomic DNA and sequenced. A total of 60 kb of bi-directional sequence was generated from each of 93 human DNAs, which included Caucasian, African-American and Asian samples. There were 388 different polymorphisms identified. These included 269 non-coding, 45 synonymous and 74 non-synonymous polymorphisms. Of these, 54% were novel and included 176 non-coding, 14 synonymous and 21 non-synonymous polymorphisms. Of the novel variants observed, 85 were represented by single occurrences of the minor allele in the sample set. Much of the variation observed was from low-frequency alleles. Comparatively, these genes are variation-rich. Calculations measuring genetic diversity revealed that while the values for the individual genes are widely variable, the overall nucleotide diversity of 7.7 x 10(-4) and polymorphism parameter of 11.5 x 10(-4) are higher than those previously reported for other gene sets. Several independent measurements indicate that these genes are under selective pressure, particularly for polymorphisms corresponding to non-synonymous amino acid changes. There is relatively little difference in measurements of diversity among the ethnic groups, but there are large differences among the genes and gene subfamilies themselves. Of the three CYP subfamilies involved in phase I drug metabolism (1, 2, and 3), subfamily 2 displays the highest levels of genetic diversity.  相似文献   
173.
The alpha2B-adrenergic receptor (ADRA2B) plays an important role in vasoconstriction and blood pressure regulation. One common variant in the ADRA2B gene (del 301--303) has been identified, and results in markedly decreased receptor desensitization in vitro but does not alter vascular sensitivity in vivo. Therefore, we fully characterized genetic variations in ADRA2B and related them to phenotype in vivo. We examined 5812 bp of contiguous sequence of ADRA2B (promoter, exonic, and 3'-untranslated region; 3'-UTR) using the polymerase chain reaction to amplify the genomic target followed by bidirectional sequencing (n=68). Haplotypes were inferred using an expectation maximization algorithm. Vasoconstriction in response to increasing doses of the highly selective alpha2-adrenergic receptor agonist, dexmedetomidine (0.01--1000 ng/min) was measured in the dorsal hand vein using a linear variable differential transformer. The dose that produced 50% (ED50) of maximum venoconstriction (Emax) was determined for each subject from the individual dose--response curves. ED50 and Emax were compared in subjects with and without variant alleles and haplotypes of interest. We identified 24 variable sites, 12 in the promoter region, five in the coding region (including two previously described as non-synonymous variants) and seven in the 3'-UTR region. Four haplotypes were inferred, representing approximately 95% of the cohort. One haplotype, characterized by two single nucleotide polymorphisms in the promoter region, and one in the 3'-UTR, occurred in seven of 38 African-Americans, and was associated with a lower Emax, 61.3% [95% confidence interval (CI) 39.5--83.0, n=7] compared to 78.1% (CI 73.8--82.5) in wild-types (n=61) (P=0.02). There was no association between the nine common variants and dexmedetomidine ED50. We have described novel variants and haplotypes of the ADRA2B gene. These do not alter sensitivity to a selective alpha2-adrenergic receptor agonist but some may decrease maximal venoconstriction in vivo.  相似文献   
174.
Objectives The aim of this study was to investigate the psychometric properties of the Greek version of the Pediatric Quality of Life InventoryTM 4.0 (PedsQLTM 4.0) as a population health outcome measure. Methods After cultural linguistic validation, a cross-sectional study with the participation of 645 children (8–12 years old) and their primary caregivers was conducted in a nation-wide representative school-based sample to evaluate the psychometric properties of the measure. Results All PedsQL 4.0 scales showed satisfactory reliability, with Cronbach’s α exceeding 0.70—except in self-reported Physical Functioning (α = 0.65). Test–retest stability intraclass correlation coefficients (ICCs) were above 0.60 in all subscales. No floor effects were detected in either the self-report or parent proxy versions. Ceiling effects ranged from 2.2% (self-report Total Score) to 31.1% (parent-report Social Functioning). Poor to moderate agreement between self report and proxy report was observed, especially for the younger age groups of children. Impact of gender, health status, and family affluence status were detected, as hypothesised from previous bibliography, with girls reporting lower health-related quality of life (HRQOL) than boys on the Emotional Functioning subscale, healthy children scoring significantly higher on all scales than those with chronic illnesses, and lower socioeconomic groups scoring significantly lower than higher socioeconomic groups. Factor analysis showed mainly comparable results with the original version. Conclusions Present results support the reliability and validity of the PedsQL 4.0 Greek version. The instrument could be a valuable tool in HRQOL measurement in school health care settings and population-based studies in Greek-speaking children, though it should be stressed that when possible, the child should be considered the first informant of his/her HRQOL.  相似文献   
175.
Forensic Toxicology - The purpose of this review is to summarize the existing knowledge on flualprazolam, a novel ‘designer’ benzodiazepine that derives from the fluorination of the...  相似文献   
176.
The pleomorphic adenoma (PA) or mixed tumor is the most common neoplasm of the salivary glands, usually presenting with a non-specific clinical manifestation and a diverse histopathological pattern. The region of the lips is the second most common site for minor gland neoplasms. The aim of this paper is to report the case of a 39 year old caucasian woman presenting with a swelling on the right side of the upper lip combined with a history of trauma in the region of the upper right central incisor, eight years ago. The swelling was attributed to the periapical lesion of the upper right central incisor that was observed on the orthopantomography. Intraoperatively the surgeon came upon a nodule of firm consistency in the mucolabial fold. The histopathologic diagnosis of this lesion was benign mixed tumor of salivary gland. This report discusses the deviation in frequency of mixed salivary gland tumor between upper and lower lip, the clinical differential diagnosis, the histopathological pattern and the appropriate treatment.Key words: Pleomorphic Adenoma, Lip, Salivary Glands, Minor  相似文献   
177.
Purpose

Fentanyl analogues are popular in recent years among drug addicts and have been related to many overdoses and deaths worldwide. Furanylfentanyl, ocfentanil, acetylfentanyl and butyrfentanyl are among the most common of these drugs. Methods for the determination of furanylfentanyl and ocfentanil by gas chromatography–mass spectrometry (GC–MS) in biological samples do not exist, and therefore, their development would be extremely useful for routine toxicological analysis.

Methods

A GC–MS method was developed and fully validated for the determination of furanylfentanyl and ocfentanil in whole blood. This method was also suitable for the determination of acetylfentanyl and butyrfentanyl. The method included solid-phase extraction after protein precipitation using acetonitrile, and it was applied during the toxicological investigation of forensic cases. Methadone-d3 was used as internal standard for the quantification of the analytes.

Results

The limit of detection and limit of quantification values were 0.30 and 1.0 ng/mL for furanylfentanyl and ocfentanil and 0.15 and 0.50 ng/mL for acetylfentanyl and butyrfentanyl, respectively. The calibration curves were linear (R2?≥?0.993) from 1.00 to 100 ng/mL for furanylfentanyl and ocfentanil and from 0.50 to 50.0 ng/mL for acetylfentanyl and butyrfentanyl. The recoveries were not lower than 85%, while accuracies and precisions were not greater than 6.0% (% error) and 8.0% (% relative standard deviation), respectively, for all four fentanyl analogues.

Conclusions

The developed method is the first one in the literature for the detection of furanylfentanyl and ocfentanil in biological fluids by GC–MS, and it provides very high sensitivity comparable to that by liquid chromatography–tandem mass spectrometry.

  相似文献   
178.
Group A rotaviruses (RVs) are important pathogens that cause acute, dehydrating gastroenteritis in infants and young children. In this study, a multiplex real-time polymerase chain reaction protocol using primers and TaqMan(?) probes specific for viral VP4 and VP7 genes was evaluated. This assay offers simultaneous genotyping and quantification of the most common RV genotypes G1P[8], G2P[4], G3P[8], G4P[8], and G9P[8]. It was compared to the molecular typing results provided by conventional PCR. A total of 92 archived stool specimens obtained from children younger than 5 years old with the diagnosis of acute gastroenteritis were examined. Real-time PCR assay detected rotavirus strains among the most common genotype combinations G4P[8] (70.7%), G1P[8] (10.9%), G2P[4] (5.4%), G9P[8] (2.2%). This new assay described has an acceptable sensitivity (low limit 6.3×10(2)copies/g of stool).  相似文献   
179.

Background

The death rate from colorectal cancer is high and affects poor and medically underserved populations disproportionately. In the United States, health disparities are particularly acute in the Lower Mississippi River Delta region. Because many in the region have limited access to basic health care resources, they are not screened for cancer, even though screening is one of the most effective strategies to prevent colorectal cancer. Community-based participatory research is a promising approach to prevent colorectal cancer in this population.

Community Context

The Empowering Communities for Life program was implemented in 2 underserved counties in the Arkansas Lower Mississippi River Delta. The program arose from a 9-year partnership between the University of Arkansas for Medical Sciences and 9 cancer councils across Arkansas.

Methods

Empowering Communities for Life is a community-based participatory intervention designed to increase colorectal cancer screening in rural, underserved communities through fecal occult blood testing. Community and academic partners collaborated to develop research infrastructure, intervention materials and methods, and the assessment instrument.

Outcome

Project outcomes were strengthened community-academic partnerships, certification of community partners in conducting human subjects research, development of a randomized controlled design to test the intervention''s efficacy, an interactive PowerPoint presentation, an informational pamphlet, the certification of 6 lay health advisors and 22 role models to provide the intervention, and an assessment tool using an audience response system.

Interpretation

Lessons learned in working collaboratively with diverse groups include the importance of meeting face to face and listening.  相似文献   
180.
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