DNA transfer when using gloves in burglary simulations

Several studies have demonstrated that DNA can be indirectly transferred from an individual onto a surface. Therefore, the presence of DNA that is compatible with a given person does not necessarily mean that this person has touched the surface on which the DNA was recovered. The present work simulates cases, where DNA is recovered on a door handle and compared to several reference DNA profiles. The DNA profile of the trace shares DNA components with a person of interest (POI). When asked about the DNA results, the POI says he has nothing to do with the incident and has never been at the scene. However, a possibility would be that the DNA came from his recently stolen gloves. Someone else, the alternative offender (AO), could have opened the door wearing his gloves (POI's gloves), and transferred his DNA (POI's DNA). Based on the above-mentioned scenario, 60 burglary simulations experiments were carried out to generate data to assess DNA results given these allegations. The quantity and quality of DNA profiles (NGM SElect) recovered when the POI opened/closed the door bare-handed or when someone else performed the same activity but using POI's gloves, were compared. The gloves were regularly worn during at least three months by their owner during the winter. On the contrary, the AO wore them only for two minutes. Among the traces collected on the door handles, less than 50% of the traces led to interpretable DNA profiles. In 30% of the cases (3/10), when the door was opened/closed with bare hands, the DNA found on the door handle led to a mixed DNA profile with the POI's DNA aligning with the major contributor. For the experiments where the AO opened/closed the door with the POI's gloves, the POI's DNA was compatible with 22% (11/50) of the mixed DNA profile, aligning with the major in 8% of the cases (4/50). The DNA profiles of the offices' occupants were observed on the door handles, but not the AO's. In addition to the results of the experiments, we show two examples of how one can assess results observed in casework. Given the possibility of indirect transfer of minute DNA quantities, this research emphasizes the need to evaluate DNA results given the activities when the POI has a legitimate reason that can explain the presence of their DNA.

Root cause analysis applied to the investigation of serious untoward incidents in mental health services

The Department of Health publication Building a Safer NHS for Patients sets out the Government's plans for promoting patient safety (Department of Health, 2001). This follows growing international recognition that health services around the world have underestimated the scale of unintended harm or injury experienced by patients as a result of medical error and adverse events occurring in health care settings. These plans include a commitment to replace the procedures set out in the Department of Health circular HSG(94)27. This guidance details the methods for investigating every homicide (and some suicides) by patients in current or recent contact with specialist mental health services. Part of the process to modernise HSG(94)27 includes a plan to build expertise within the National Health Service (NHS) in the technique of root cause analysis. This investigative process was developed in industry to identify causal or systems factors in serious adverse events.

The Effects of a BDNF Val66Met Polymorphism on Posttraumatic Stress Disorder: A Meta-Analysis

OBJECTIVE

Given evidence that posttraumatic stress disorder (PTSD) is moderately heritable, a number of studies utilizing candidate gene approaches have attempted to examine the potential contributions of theoretically relevant genetic variation. Some of these studies have found sup port for a brain-derived neurotrophic factor (BDNF) variant, Val66Met, in the risk of developing PTSD, while others have failed to find this link.

METHODS

This study sought to reconcile these conflicting findings using a meta-analysis framework. Analyses were also used to determine whether there is significant heterogeneity in the link between this variant and PTSD. We conducted a systematic review of the literature on BDNF and PTSD from the PsycINFO and PubMed databases. A total of 11 studies were included in the analysis.

RESULTS

Findings indicate a marginally significant effect of the BDNF Val66Met variant on PTSD (p < 0.1). However, of the 11 studies included, only 2 suggested an effect with a non-zero confidence interval, one of which showed a z score of 3.31. We did not find any evidence for heterogeneity.

CONCLUSIONS

Findings from this meta-analytic investigation of the published literature provide little support for the Val66Met variant of BDNF as a predictor of PTSD. Future well-powered agnostic genome-wide association studies with more refined phenotyping are needed to clarify genetic influences on PTSD.

Use of DNA profiles for investigation using a simulated national DNA database: Part I. Partial SGM Plus profiles

In traditional criminal investigation, uncertainties are often dealt with using a combination of common sense, practical considerations and experience, but rarely with tailored statistical models. For example, in some countries, in order to search for a given profile in the national DNA database, it must have allelic information for six or more of the ten SGM Plus loci for a simple trace. If the profile does not have this amount of information then it cannot be searched in the national DNA database (NDNAD). This requirement (of a result at six or more loci) is not based on a statistical approach, but rather on the feeling that six or more would be sufficient. A statistical approach, however, could be more rigorous and objective and would take into consideration factors such as the probability of adventitious matches relative to the actual database size and/or investigator's requirements in a sensible way. Therefore, this research was undertaken to establish scientific foundations pertaining to the use of partial SGM Plus loci profiles (or similar) for investigation.

A model for estimating the number of glass fragments transferred when breaking a pane: experiments with firearms and hammer

Numerous publications have shown the importance of transfer in the interpretation of glass evidence. As this phenomenon is also highly variable, it was decided to test the hypothesis that there exists a means to predict the number of fragments recovered at time t = 0. Panes of float glass-of different types and thickness-were broken using either a firearm or a hammer. It was decided to choose a firearm as the main breaking device, as it allowed not only to have more reproducible conditions but also to acquire knowledge in a field where little has been published. Despite the inherent variation in the breaking process, the results show that using a statistical model it is possible to predict the number of fragments transferred onto a garment from the number of fragments transferred to the ground. This research also indicates the size and number of particles transferred onto a person, when breaking window panes of different types (float, laminated or toughened) with different breaking procedures.

The classification and discrimination of glass fragments using non destructive energy dispersive X-ray μfluorescence

Frequency of analytical characteristics is best estimated on glass recovered at random. However, as such data were not available to us, we decided to use control windows for this estimation. In order to use such a database, one has to establish that the recovered fragment comes from a window. Therefore, elemental analysis was used both for classification and discrimination of glass fragments. Several articles have been published on the subject, but most methods alter the glass sample. The use of non destructive energy dispersive X-ray microfluorescence (microXRF) for the analysis of small glass fragments has been evaluated in this context. The refractive index (RI) has also been measured in order to evaluate the complementarity of techniques. Classification of fragments has been achieved using Fisher's linear discriminant analysis (LDA) and neural networks (NN). Discrimination was based on Hotelling's T2 test. Only pairs that were not differentiated by RI followed by the Welch test were studied. The results show that neural network and linear discriminant analysis using qualitative and semi-quantitative data establishes a classification of glass specimens with a high degree of reliability. For discrimination, 119 windows collected from crime scene were compared: using RI it was possible to distinguish 6892 pairs. Out of 129 remaining pairs, 112 were distinguished by microXRF.

Assessing transfer probabilities in a Bayesian interpretation of forensic glass evidence

When someone breaks glass a number of tiny fragments may be transferred to that person. If the glass is broken in the commission of a crime then these fragments may be used as evidence. A Bayesian interpretation of this evidence relies on the forensic scientist's ability to assess the probability of transfer. This paper examines the problem of assessing this probability and suggests some solutions.

Perineal repair of rectal prolapse

Perineal approaches to the repair of rectal prolapse are frequently used in elderly or high-risk patients. These repairs have lower operative mortality and morbidity than intra-abdominal repairs but in general have higher recurrence rates. This study reviews our recent results with perineal prolapse repairs, briefly summarizes the literature, and discusses the available perineal operations. Eight patients (mean age 75 years) underwent surgical prolapse repair over an 18-month period. Treatment was by Altemeier's procedure (perineal rectosigmoidectomy) in 6 patients and Delorme's procedure in 2 patients. There were no operative mortalities, and an anastomotic dehiscence in 1 patient was managed nonoperatively. All patients with preoperative constipation improved and no patient reported worsening of continence. Surgical approaches from the perineum may be used in elderly and poor risk patients to treat rectal prolapse with low mortality and morbidity. These techniques have not adversely affected fecal continence and have improved symptoms of constipation with an acceptable rate of recurrence.

Procedures used by North Carolina dairies for vitamins A and D fortification of milk

New research findings have documented fortification errors in fortified milk products all across the US milk industry. Also, the consumption of overfortified bovine milk has led the public to question whether vitamin fortification is safe. Therefore, North Carolina dairies were surveyed to determine vitamin fortification procedures used and to determine differences among these procedures. Of the parameters surveyed, the general conditions under which vitamin preparations were stored, the method used to add vitamin preparations to milk, and the point during processing at which vitamin preparations were added to milk were different among dairies. Forty-six percent of the dairies stored vitamin preparations under refrigerated conditions, and 54% stored vitamin preparations at ambient temperatures. The addition of vitamin preparations to bovine milk was accomplished by metered injection at 64% of the dairies and batch addition techniques at 36%. Vitamin preparations were added before fat content standardization and separation by 23% of the dairy processors; 77% added the vitamin preparations after this point. When dairies were asked at what point they added their vitamin preparations to the milk, nine different answers were given. Although other sources of error could also contribute to inconsistent concentrations of vitamin fortification, differences in fortification procedures may have a large impact upon the problem. The diversity of vitamin fortification practices used in North Carolina may be an indication of nationwide trends.

Practice parameters for sigmoid diverticulitis. The Standards Task Force American Society of Colon and Rectal Surgeons

It should be recognized that these guidelines should not be deemed inclusive of all proper methods of care or exclusive of methods of care reasonably directed to obtaining the same results. The ultimate judgment regarding the propriety of any specific procedure must be made by the physician in light of all of the circumstances presented by the individual patient.

Congenital cytomegalovirus infection and neonatal auditory screening

Auditory screening of newborn infants has been recommended on the basis of the presence of risk criteria, including congenital infection. We assessed the ability of risk criteria-based neonatal auditory brain stem response to identify infants with hearing loss resulting from congenital cytomegalovirus (CMV) infection. Data from 6 1/2 years of risk criteria-based neonatal auditory screening were compared with the results of screening of all newborn infants for congenital CMV infection. Infants with congenital CMV infection received follow-up hearing evaluations. Congenital CMV infection was found in 167 (1.3%) of 12,371 infants; 134 had follow-up hearing evaluations, and 14 (10.4%) had confirmed sensorineural hearing loss. The rate of sensorineural hearing loss resulting from congenital CMV infection was 14 per 12,371 infants, of 1.1 per 1000 live births; the rate of bilateral loss > or = 50 dB was 0.6 per 1000. Although 2036 infants received auditory screening because of risk criteria, only 34 (20%) of 167 infants with congenital CMV infection were included. Only 2 (14%) of 14 children with sensorineural hearing loss caused by CMV were identified by risk criteria-based screening. We conclude that congenital CMV infection is an important cause of hearing impairment. Neonatal auditory screening based on the presence of risk criteria will fail to identify the majority of cases of sensorineural hearing loss caused by congenital CMV infection.

Utilization of dental services by older adults in four Ontario communities

The elderly tend to use dental services less than most younger age groups. While the elderly's utilization rates may be rising, very low utilization by edentulous people depresses the overall rate for the group. We use data from the Ontario Study of the Oral Health of Older Adults to identify the variations in the use of dental services in the four study sites of Toronto, North York, Simcoe County and Sudbury and District. We reached 3,033 subjects by telephone and conducted dental examinations and a multi-item personal interview with 907 of them. The 907 subjects ranged in age from 50 to 87 years, 57 percent were female and two-thirds were born in Canada. Overall, 60.5 percent had seen a dentist or denturist in the previous year, but this was much lower among the edentulous (17 percent) when compared to the dentate (72 percent) (Chi-square test; p less than .0001). Of the 357 who did not visit a dentist or denturist in the previous year, nearly half (48 percent) felt they had nothing wrong and 20 percent reported they could not afford care. A high proportion (94 percent) of the edentulous reported visiting only for pain or trouble compared to 26 percent of the dentate (Chi-square test; p less than .0001). Using logistic regression, we found dental status (edentulous), community of residence (Sudbury), income (up to $20,000) and dental insurance coverage (none) were important factors in not making a dental visit in the last year. These same factors, plus education (elementary) were important where subjects reported visiting a dentist or denturist only when there was pain or trouble.

Extracellular pH, transmembrane distribution and cytotoxicity of chlorambucil

The effects of extracellular pH (6.2 to 7.3) on uptake and cytotoxicity of the weak acid anti-tumor drug chlorambucil were investigated. Decreasing extracellular pH from 7.3 to 6.5 had a negligible effect on the intracellular pH of Chinese hamster V79 fibroblasts, thus resulting in the formation of a transmembrane pH gradient (intracellular alkaline). Addition of high concentrations of acetate or bicarbonate partially collapsed the pH gradient. Chlorambucil (pKa = 5.8) behaved as a weak acid with enhanced accumulation and cytotoxicity at extracellular pH less than 7.0. As predicted for a weak acid, partial collapse of the transmembrane pH gradient decreased both uptake and cell killing. Since the interstitial pH of micrometastases and solid tumors of many cancers is low relative to normal tissues, these results have potential implications for both in vitro drug testing and in vivo therapy.

Multiple ureteral diverticula

Only 30 cases of multiple ureteral diverticula have been reported previously. We present a new case of this benign condition and review concepts concerning its etiology. Usually discovered on retrograde pyelography, multiple ureteral diverticula are only inconsistently associated with a history of obstruction or infection. When present, however, these factors may play a role in precipitating mucosal herniation through preexisting weak areas in the ureteral wall.

Succinylcholine chloride as a euthanatizing agent in dogs

In order to determine the efficacy of succinylcholine chloride as a euthanatizing agent, the possible situation encountered in mass euthanasia was recreated. While anesthetized or awake, sixteen 2-year-old Beagles of both sexes were subcutaneously injected with either 1.1 g or 11 mg of succinylcholine chloride/kg of body weight. Positive pressure respiration was given to 2 dogs, otherwise the treatment was allowed to run its course. Electrocardiogram, electroencephalogram, and impedance pneumogram recordings were obtained for time comparisons and for determination of the ultimate cause of death.

Regulation of some functions of granulocytes by zinc of the prostatic fluid and prostate tissue

Oxygen consumption, phagocytosis, and activity of hexosomonophosphate shunt (HMS) of dog and human polystyrene latex-activated polymorphonuclear leukocytes were inhibited by normal and infected human prostatic fluid (PF) and prostate extract; resting cells were not affected. Granulocytes incubated in 7 per cent PF increased five times their zinc content. Inorganic zinc added to synthetic medium which contained activated granulocytes also inhibited O2 consumption and phagocytosis of yeast particles in a concentration-dependent manner; resting cells were not affected. Incubation of PF with CaNa2 ethylenediamine tetraacetic acid (EDTA) abolished the inhibitory effect of PF; extensive dialysis of PF against this chelating agent reduced the inhibition by half. After the PF was dialyzed against saline, the low molecular weight dialysate retained inhibitory effects. Extracts from dog liver, spleen, and human saliva were not inhibitory. Polyamines, which next to zinc are also present in PF in high concentrations, had no effect on granulocytes, O2 consumption, and HMS activity. Human as well as dog PF were inhibitory to human or dog granulocytes, respectively. Besides granulocytes, rat peritoneal macrophages were inhibited by PF as well. It is concluded that PF and extract from prostate inhibit various functions of phagocytes mainly because of high concentration of zinc. The existence of other, large molecular weight, heat-resistant substances in PF which contribute to zinc effect cannot be ruled out.

Vascular spider: a cutaneous manifestation of hyperdynamic blood flow in hepatic cirrhosis

Arteriography and gas analysis of blood aspirated from a vascular spider in a patient with hepatic cirrhosis were done before excision and histologic examination of the lesion. This study supports earlier work suggesting that a spider angioma is a cutaneous manifestation of a generalized hyperdynamic circulation in hepatic cirrhosis. Moreover, based upon a variety of experimental and clinical observations on the splanchnic circulation in cirrhosis, it is suggested that the portal hypertension blood flow encounters the obstacle posed by the scarred liver ("active congestion").

The influence of secretin on ion transport in the human jejunum

Using a triple-lumen tube perfusion technique in normal human subjects secretin (2U/kg/hour intravenously) was shown to reduce the absorption of sodium, potassium, and chloride in the most proximal 30 cm of jejunum but it had no effect on bicarbonate absorption. This effect was not due to an artefact produced by the entry of secretin-stimulated, bicarbonate-rich, pancreatic juice into the test segment. Absorption of sodium chloride and water was stimulated rather than inhibited by higher bicarbonate concentrations and the effect of secretin was obvious even when this factor was controlled by adjusting the bicarbonate concentrations of the test fluids. Secretin did not influence ion transport in the mid-jejunum. It is suggested that the effects described may indicate a physiological role for secretin in the intestine where it could prevent the too rapid dehydration of upper jejunal contents which might interfere with adequate mixing and digestion.