This new analysis of 194 DNA exonerations, representing 171 criminal events, examines the types of evidence and DNA testing that have been used to free the victims of wrongful conviction. The types of DNA testing used to free the innocent... more
This new analysis of 194 DNA exonerations, representing 171 criminal events, examines the types of evidence and DNA testing that have been used to free the victims of wrongful conviction. The types of DNA testing used to free the innocent parallels the growth of these techniques in forensic science. Short tandem repeat (STR) analysis now prevails (70%), though Y-STR analysis (16%) and mitochondrial testing (10%) are still used when STR analysis is not feasible, and the recently developed mini-STRs have been used for exonerations since 2008 (2.6%). The types of exculpatory evidence included intimate swabs (65%), clothing (53%), hair (13%), fingernail evidence (5%), cigarettes (3%), and other evidence. The most common factor associated with wrongful convictions was misidentification (75%), including misidentification by the victim (65%). False confessions (including admissions and pleas) were obtained in 30% of the cases, and informant testimony (including jailhouse and government inf...
A total of 129 clinical isolates of Mycobacterium tuberculosis representing 91 patients were typed by a combination of direct-repeat (DR)-based spoligotyping and an inter-IS6110-PGRS (polymorphic GC-rich region)-PCR, also designated... more
A total of 129 clinical isolates of Mycobacterium tuberculosis representing 91 patients were typed by a combination of direct-repeat (DR)-based spoligotyping and an inter-IS6110-PGRS (polymorphic GC-rich region)-PCR, also designated double-repetitive-element PCR (DRE-PCR). During the first phase of this investigation, 72 clinical strains representing 52 patients were initially typed by IS6110-restriction fragment length polymorphism (RFLP) and DR-RFLP, followed by spoligotyping and DRE-PCR. In the second phase of this investigation, the discriminating ability of spoligotyping plus DRE-PCR was studied for 57 isolates from 39 patients who were suspected to be epidemiologically linked, and the typing results were later confirmed by IS6110-RFLP and DR-RFLP analyses. The molecular clustering of the isolates remained identical irrespective of the methods used. These results show that the association of two PCR-based fingerprinting techniques for molecular epidemiology of tuberculosis has ...
Abstract: RAPD markers were used to measure the genetic diversity of 119 individuals of Ixodes ricinus collected from Lithuania and Norway. The samples were analysed within and also between the populations. We analysed 74 loci in each of... more
Abstract: RAPD markers were used to measure the genetic diversity of 119 individuals of Ixodes ricinus collected from Lithuania and Norway. The samples were analysed within and also between the populations. We analysed 74 loci in each of 6 populations. Our results show high levels of diversity within the populations. The percentage of polymorphic loci of the six analysed populations: Birzai, Vilnius, Kretinga, Tjore, Kjosvik and Odderoya were 68.9%, 58.1%, 78.38%, 62.2%, 44.6 % and 68.9%, respectively. The percentage of polymorphic loci in the Lithuanian populations was 93.2%, and in the Norwegian populations 81.08%. The genetic distance ranged from 0.019 to 0.079 within Norwegian populations and from 0.005 to 0.0967 within Lithuanian populations and between the countries from 0.022 to 0.146. The genetic variation of I. ricinus among Norwegian populations was lower than among Lithuanian populations. The highest part of genetic variation in I. ricinus ticks depends on variation withi...
Methicillin-resistant Staphylococcus aureus (MRSA) plays an important role in nosocomial infections including those in communities. MRSA enables colonization in the nares and throats of healthy people. In this study, investigation of MRSA... more
Methicillin-resistant Staphylococcus aureus (MRSA) plays an important role in nosocomial infections including those in communities. MRSA enables colonization in the nares and throats of healthy people. In this study, investigation of MRSA prevalence from the throats of healthy subjects in southern Thailand revealed that among 153 isolates, 2 showed mecA+ genotype by PCR. One mecA+ isolate was susceptible to methicillin, indicating a cryptically methicillin-resistant strain. Antimicrobial susceptibility test demonstrated that 43% were resistant to erythromycin. More importantly, two isolates had the propensity of reduced susceptibility to vancomycin. Other virulence genes harbored by 2 and 8 MRSA from healthy carriers and hospitals, respectively, exhibited that 3 clinical strains possessed coagulase gene while von Willebrand factor binding protein gene was present in one clinical MRSA strain. Staphylococcal enterotoxin A gene was found in 2 clinical MRSA isolates and Panton-Valentine...
Differential gene expression between various tissues and developmental stages or between cells in vitro under different growth conditions can be rapidly and efficiently compared using the RNA arbitrarily primed polymerase chain reaction... more
Differential gene expression between various tissues and developmental stages or between cells in vitro under different growth conditions can be rapidly and efficiently compared using the RNA arbitrarily primed polymerase chain reaction (RAP) fingerprinting method (Welsh et al., 1992b; Liang and Pardee, 1992). In RAP, a primer of arbitrary sequence primes both first and second strand cDNA synthesis. The mixture of products is then PCR amplified and resolved electrophoretically, yielding highly reproducible fingerprints that are tissue-specific or growth condition-specific. Differences between fingerprints arise from differentially expressed genes, as verified by Northern blot analysis. RAP can be performed on the RNA samples using various DNA primers. Each two day experiment yields a sample of approximately twenty cDNA products per lane making the identification of differentially or developmentally regulated genes no longer rate limiting. Those PCR products representing genes that a...
Saccharolytic, nonpigmented, anaerobic gram-negative rods isolated from infected dog and cat bite wounds in humans have been poorly characterized, and most are not included in the databases of kits used for anaerobic identification; thus,... more
Saccharolytic, nonpigmented, anaerobic gram-negative rods isolated from infected dog and cat bite wounds in humans have been poorly characterized, and most are not included in the databases of kits used for anaerobic identification; thus, they are problematic for clinical laboratories to identify. Fifty strains isolated from such wounds were characterized with commercial kits for preformed-enzyme detection, carbohydrate fermentation, and other biochemical tests. PCR fingerprinting was performed on these strains to further characterize subgroups within these species. Bacteroides tectum is a frequent isolate in bite wounds and resembles Prevotella bivia in colony morphology and saccharolytic activity, except that it grows in 20% bile and hydrolyzes esculin. Profile numbers generated by various kits associate B. tectum with P. bivia, Prevotella oralis group, or Prevotella melaninogenica. PCR fingerprinting identified at least four subgroups and confirmed the heterogeneous nature of thi...
The aim of this study was to examine the association between victim, suspect and assault characteristics and (1) forensic analysis of trace evidence, (2) detection of spermatozoa and (3) DNA match in police-reported cases of... more
The aim of this study was to examine the association between victim, suspect and assault characteristics and (1) forensic analysis of trace evidence, (2) detection of spermatozoa and (3) DNA match in police-reported cases of rape/attempted rape. In addition, we explored whether DNA findings were associated with legal outcome. We conducted a retrospective, descriptive study based on police-reported rapes and attempted rapes of women ≥16 years of age in Sør-Trøndelag Police District throughout 1997-2010. Police data were merged with information from the Sexual Assault Centre (SAC) at St. Olavs University Hospital, Trondheim, Norway. We used binary and multivariable logistic regression for the comparisons. We identified 324 victims (mean age 24 years). The police requested analysis in 135 (45%) of the 299 collected victim samples. The police decision to analyze was after adjustment associated with the victim being employed or under education, and a public venue, but not with interval ...
The use of disease-causing organisms and their toxins against the civilian population has defined bioterrorism and opened forensic science up to the challenges of processing contaminated evidence. This study sought to determine the use of... more
The use of disease-causing organisms and their toxins against the civilian population has defined bioterrorism and opened forensic science up to the challenges of processing contaminated evidence. This study sought to determine the use of gamma irradiation as an effective biological decontaminant and its effect on the recovery of latent fingermarks from both porous and nonporous items. Test items were contaminated with viable spores marked with latent prints and then decontaminated using a cobalt 60 gamma irradiator. Fingermark detection was the focus with standard methods including 1,2-indanedione, ninhydrin, diazafluoren-9-one, and physical developer used during this study. DNA recovery using 20% Chelex extraction and quantitative real-time polymerase chain reaction was also explored. Gamma irradiation proved effective as a bacterial decontaminant with D-values ranging from 458 to 500 Gy for nonporous items and 797-808 Gy for porous ones. The results demonstrated the successful recovery of latent marks and DNA establishing gamma irradiation as a viable decontamination option.
Several bacteriological surveys were performed from 1994 to 1996 at different Litopenaeus vannamei hatcheries (in Ecuador) and shrimp farms (in Mexico). Samples were taken from routine productions of healthy and diseased L. vannamei... more
Several bacteriological surveys were performed from 1994 to 1996 at different Litopenaeus vannamei hatcheries (in Ecuador) and shrimp farms (in Mexico). Samples were taken from routine productions of healthy and diseased L. vannamei larvae, postlarvae, and their culture environment and from healthy and diseased juveniles and broodstock. In Ecuador, the dominant bacterial flora associated with shrimp larvae showing symptoms of zoea 2 syndrome, mysis mold syndrome, and bolitas syndrome has been determined. Strains were characterized by Biolog metabolic fingerprinting and identified by comparison to a database of 850 Vibrio type and reference strains. A selection of strains was further genotypically fine typed by AFLP. Vibrio alginolyticus is predominantly present in all larval stages and is associated with healthy nauplius and zoea stages. AFLP genetic fingerprinting shows high genetic heterogeneity amongV. alginolyticus strains, and the results suggest that putative probiotic and pat...
To investigate phenotypically and genotypically the presence of MDR efflux pumps in 21 clinical isolates of Staphylococcus haemolyticus collected over a period of 10 years. MICs of different antibiotics and biocides were determined by the... more
To investigate phenotypically and genotypically the presence of MDR efflux pumps in 21 clinical isolates of Staphylococcus haemolyticus collected over a period of 10 years. MICs of different antibiotics and biocides were determined by the broth dilution method in the presence/absence of carbonyl cyanide-m-chlorophenylhydrazone (CCCP), an efflux pump inhibitor. PCR followed by sequencing was performed to detect the qac genes that encode for antiseptic resistance. Clonal relationships were determined by PFGE SmaI patterns using a standard protocol. All the isolates were resistant to gentamicin, 15 to erythromycin, 18 to ciprofloxacin, 7 to chloramphenicol and 1 to tetracycline. They showed higher susceptibility to antibiotics when they were exposed to CCCP. The MICs of ethidium bromide, SDS and benzalkonium chloride were also decreased, whereas the MIC of triclosan was decreased in only four isolates in the presence CCCP. Of the 21 isolates, qacA/B was detected in 5 isolates, smr in a...
