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161.
Reynolds R Walker K Varlaro J Allen M Clark E Alavaren M Erlich H 《Journal of forensic sciences》2000,45(6):1210-1231
We have developed a rapid, immobilized probe-based assay for the detection of sequence variation in the hypervariable segment II (HVII) of the mitochondrial DNA (mtDNA) control region. Using a panel of 17 sequence-specific oligonucleotide (SSO) probes immobilized on nylon membrane strips, we typed 689 individuals from four population groups. The genetic diversity value for each population was calculated from the frequency data, and the frequencies of distinct "mitotypes" in each group were determined. We performed DNA sequence analysis of 129 samples to characterize the sequences associated with "blanks" (absence of probe signals) and weak probe signals. Out of 689 samples, we observed five heteroplasmic samples (excluding the variable C-stretch beginning at position 303) using the immobilized SSO probe panel. The SSO probe strips were used for the analysis of shed hairs and bloodstains from several criminal cases in Sweden, one of which is described here. We conclude that this mtDNA typing system is useful for human identification and significantly decreases casework turnaround time. 相似文献
162.
Cooper GA Allen DL Scott KS Oliver JS Ditton J Smith ID 《Journal of forensic sciences》2000,45(2):400-406
Drug use histories were collected from 100 subjects recruited from the "dance scene" in and around Glasgow, Scotland. In addition, each subject donated a hair sample which was analyzed by gas chromatography/mass spectrometry (GC/MS) for amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MD MA) and 3,4-methylenedioxyethylamphetamine (MDEA). The hair samples were analyzed in two 6 cm segments or in full, ranging from 1.5 to 12 cm depending on the length of the hair. Approximately 10 mg of hair was ground to a fine powder before treatment with beta-glucuronidase/aryl sulfatase. A solid-phase extraction procedure was carried out followed by derivatization with pentafluoropropionic anhydride (PFPA). All extracts were analyzed by gas chromatography/mass spectrometry (GC/MS). Of the 139 segments analyzed, 77 (52.5%) were positive for at least one of the five amphetamines. The drug concentrations found in the hair were compared with the self-reported drug histories. A concordance of greater than 50% was found between the self-report data and levels detected in hair. However, no correlation was found between the reported number of "ecstasy" tablets consumed and the drug levels detected in hair. An increase in the average drug levels measured was observed from low to high use (number of "ecstasy" tablets/month). A large number of false negatives and a low number of false positives were observed. 相似文献
163.
An alternate method for quantitation of human genomic DNA is presented. Quantitative template amplification technology (abbreviated "Q-TAT") estimates the quantity of human DNA present in an extract by comparing fluorescence in X and Y amplicons produced from unknowns with fluorescence in a standard curve amplified from known quantities of reference DNA. Q-TAT utilizes PCR and electrophoresis with fluorescent detection/quantitation, precluding the need for new instrumentation, methodology, or quality assurance associated with slot-blot or real-time PCR. In a comparison study incorporating shared samples, Q-TAT was found to be more sensitive than widely used slot-blot methods but somewhat less sensitive than real-time PCR. Among samples containing DNA concentrations ranging from 100 pg/microL to 2-4 ng/microL, Q-TAT produced DNA concentration estimates that agreed reasonably well with either Quantiblot or real-time PCR. Q-TAT was reproducible with a typical coincidence of variation of about 35%. Quantitation of human DNA in this study involved summing fluorescence in X and Y amplicons in unknowns and quantitation standards. However, analyzing fluorescence in X and Y amplicons individually could allow estimates of male and female DNA present in mixtures to be made. Moreover, since X and Y amplicons exhibit sizes of 210 and 216 bp, respectively, the integrity as well as the concentration of the genomic DNA template can be assessed. Q-TAT represents an alternate method useful for the quantitation of human genomic DNA prior to amplification of STR loci used for identity testing purposes. The method uses existing equipment and procedures in conjunction with a well-characterized DNA standard to produce concentration estimates for unknowns that reliably produce STR profiles suitable for analysis. 相似文献
164.
Schuyler D Liang BA 《Annals of health law / Loyola University Chicago, School of Law, Institute for Health Law》2006,15(2):275-305, table of contents
This article focuses on the phenomenon of elder abuse, which is one of the paramount symptoms of the larger community's failure to address the social, medical, and legal needs of the senior populace. Although there have been multidisciplinary efforts to address this problem, they are not responsive to the needs of the senior population itself In response, the authors propose a model that takes into account the specific concerns of local senior communities and provides seniors and their stakeholder providers a stable infrastructure to ensure open, consistent, and effective participation and delivery of services. 相似文献
165.
166.
DNA quantification of forensic evidence is very valuable for an optimal use of the available biological material. Moreover, sex determination is of great importance as additional information in criminal investigations as well as in identification of missing persons, no suspect cases, and ancient DNA studies. While routine forensic DNA analysis based on short tandem repeat markers includes a marker for sex determination, analysis of samples containing scarce amounts of DNA is often based on mitochondrial DNA, and sex determination is not performed. In order to allow quantification and simultaneous sex determination on minute amounts of DNA, an assay based on real-time PCR analysis of a marker within the human amelogenin gene has been developed. The sex determination is based on melting curve analysis, while an externally standardized kinetic analysis allows quantification of the nuclear DNA copy number in the sample. This real-time DNA quantification assay has proven to be highly sensitive, enabling quantification of single DNA copies. Although certain limitations were apparent, the system is a rapid, cost-effective, and flexible assay for analysis of forensic casework samples. 相似文献
167.
Mailloux DL Abracen J Serin R Cousineau C Malcolm B Looman J 《International journal of offender therapy and comparative criminology》2003,47(2):171-184
A sample of 337 offenders who received treatment in a variety of sex offender treatment programs in the Ontario region of Correctional Service Canada between 1993 and 1998 were divided based on the highest intensity sex offender programming that they received (low, moderate, and high). The three groups were compared with reference to a variety of actuarial risk assessment measures, criminogenic factors, and the number and type of treatment programs completed. It was hypothesized that the high-intensity group would have more criminogenic risk factors, higher actuarial scores, and participate in more treatment programs than both the moderate- and low-intensity groups. The results indicate that in general, the hypotheses were supported. Nonetheless, the results suggest that the low-intensity group may be receiving too much sex offender-specific treatment. 相似文献
168.
A comparison of adjustment methods to test the robustness of an STR DNA database comprised of 24 European populations 总被引:3,自引:0,他引:3
Gill P Foreman L Buckleton JS Triggs CM Allen H 《Forensic science international》2003,131(2-3):184-196
An aim of the European Network of Forensic Science Institutes (ENFSI) is to produce a DNA database of second generation multiplex (SGM) STR profiles that is representative of the resident cosmopolitan populations. To achieve this, data were collected from 24 different populations. All of the data were combined to form one database of 5700 profiles from which allele proportions were calculated. The robustness of this combined European database was tested by estimating parameter d for every DNA profile, where d=log(10)(Pm(c)/Pm(E)) Pm(c) is the match probability of the profile calculated from its cognate database and Pm(E) is the match probability of the combined European database. Overall there was a small tendency for Pm(c)>Pm(E) primarily because of sampling bias. This bias was removed by the simple expediency of applying an adjustment factor to the calculation of Pm(E). These were selected from the Balding size bias correction, the Balding and Nichols Fst correction, a minimum allele proportion (between 0.01 and 0.02), an upper bound of a 95% confidence interval (CI) and a lower bound on the genotype match probability. It was demonstrated that a single European database is a feasible proposition. A combination of different adjustment methods can be used to ensure that the result is conservative relative to the cognate database, and their effect measured by parameter d. 相似文献
169.
170.
The need to obtain dependable access to the vascular system constitutes a significant component in the treatment and management of critically ill patients. Intravenous chemotherapy administered to cancer patients over an extended period of time often results in loss of peripheral vascular access due to vein sclerosis, "exhaustion" or tissue necrosis. Medical investigators have designed and steadily upgraded a variety of devices constructed to improve venous access for long-term utilization. As with the introduction of any foreign object into the body, each of these devices has complications which may be life threatening and occasionally fatal. We present an unusual case of iatrogenic acute hydropericardium and cardiac tamponade caused by the percutaneous infusion of chemotherapeutic fluid via a right subclavian central venous implant system (Port-a-Cath). Failure to implant and monitor the device with a radiograph following placement according to manufacturer's guidelines and accepted standards of medical practice were causally related to an unusual complication, namely, perforation of the right cardiac ventricle by the catheter tip, resulting in sudden and unexpected cardiac death. 相似文献