Detection of blood and DNA traces after thermal exposure: a critical appraisal

International Journal of Legal Medicine -     

The use of the dual-task paradigm in detecting gait performance deficits following a sports-related concussion: A systematic review and meta-analysis

ObjectivesThe purpose of this systematic review was to determine the viability of the dual-task paradigm in the evaluation of a sports-related concussion.DesignSystematic review and meta-analysis.MethodsEight electronic databases were searched from their inception until the 11^th of April 2011. Studies were grouped according to their reported gait performance variables and their time(s) of assessment(s). Raw mean differences (MD) and 95% confidence intervals (CI) were calculated based on raw means and standard deviations for gait performance measures in both single- and dual-task conditions. Dual-task deficits were pooled using a random effects model and heterogeneity (I²) between studies was assessed.ResultsTen studies representing a total sample of 168 concussed and 167 matched (age and gender) non-concussed participants met the inclusion criteria. Meta-analysis demonstrated that dual-task performance deficits were detected (p < 0.05) in the concussed group for gait velocity (GV) (MD = ?0.133; 95% CI ?0.197, ?0.069) and range of motion of the centre of mass in the coronal plane (ML-ROM) (MD = 0.007; 95% CI 0.002, 0.011), but not in the non-concussed group; GV (MD = ?0.048; 95% CI ?0.101, 0.006), ML-ROM (MD = 0.002; 95% CI ?0.001, 0.005).ConclusionsThe results of this study indicate that GV and ML-ROM are sensitive measures of dual-task related changes in concussed patients and should be considered as part of a comprehensive assessment for a sports-related concussion.     

The use of thermal energy in ankle instability

With appropriate indications, ankle arthroscopy can be of significant benefit to both the patient and physician. The additional use of thermal energy significantly enhances surgical techniques. Midterm follow-up of thermal treatment of ankle instability demonstrates excellent patient satisfaction, with preserved stability, good overall function, and return to sports. Further long-term follow-up studies will continue to provide us with data that will help guide the expansion of uses of thermal energy about the ankle in a safe and efficacious manner.     

The use of thermal energy in ankle arthroscopy

Arthroscopy has proven to be a useful technique in the diagnosis and treatment of multiple ankle disorders. The confines of the joint, however, pose unique problems for arthroscopic instrumentation. Because of its adaptability, the electrothermal technique significantly enhances the arthroscopic approach to multiple soft tissue lesions about the ankle, including synovial disease, impingement, and instability.     

The use of iridium-191m for pulmonary blood flow imaging

A preliminary evaluation of the potential utilisation of osmium-191/iridium-191m for pulmonary blood flow imaging was performed. This evaluation was part of a more general study concerning the use of ^191mIr for first-pass radionuclide angiocardiography (FPRNA). In eight selected patients with suspected pulmonary disease, we generated, from the data collected during FPRNA, an image representing blood flow distribution to the lungs. A software program was developed in order to differentiate the lungs from the heart, to define the wash-in lung phase and finally to construct an image representing pulmonary blood flow distribution. We compared that image with a standard lung perfusion image using technetium-99m macroaggregated albumin (MAA) and plain chest X-ray and computerized tomography (CT). The obtained ^191mIr perfusion images showed a spatial activity distribution similar to that seen on ^99mTc-MAA lung perfusion scans, and in most cases the same perfusion defects. Disease revealed by plain chest X-ray and CT was nicely correlated with perfusion defects seen on the ^191mIr images. The combined information of lung perfusion and dynamic cardiac parameters obtained by FPRNA (right and left ventricular ejection fractions) added another relevant dimension to the clinical picture of patients with pulmonary embolism, chronic obstructive lung disease, lung tumour or suspected congestive heart failure. We conclude that ^191mIr may become a practical tool for achieving the conceptually promising approach of combined lung-heart real-time imaging. Correspondence to: M. Bocher     

数字血管减影中kVp及mAs选择对患者剂量及低对比度血管检出能力的影响

目的分析数字血管减影中kVp及mAs设置对患者皮肤剂量、有效剂量及低对比度血管检出能力的影响。方法以不同浓度碘造影剂自制低对比度血管减影体模，保持影像增强器输入端X射线比释动能为1．1μGy／帧，改变不同kVp设置，测量体模表面X射线入射剂量ESD，观察影像，确定可检测的最低碘造影剂浓度。管电压保持70kV，改变mAs设置，测量影像增强器输入端每帧影像所需X射线空气比释动能、体模ESD剂量及可检测的最低碘造影及浓度。以Monte Carlo模拟程序PCXMCV1．5模拟计算有效剂量。结果体模ESD及患者有效剂量随mAs呈线性变化。保持影像增强器输入端空气比释动能1．1μGy／帧，kVp由50变化到100，体模DSA影像可分辨的最低碘造影剂浓度线性增大；保持管电压70kV，mAs由6．4变化到64，体模DSA影像可分辨的最低碘造影剂浓度按指数规律减小。当曝光量（mAs）超过40后，其对低对比度血管检出的影响不明显。结论对DSA系统而言，降低X射线机管电压要比增大X射线机输出强度更能有效改善其低对比度血管的检测能力。     

健康风险评估系统对血脂检测的对比研究

 目的 探讨健康风险评估(health risk appraisal,HRA)系统对体检人群血脂水平的检测应用价值。 方法 选取来我院体检中心健康体检的235人作为研究对象,对其进行统一问卷调查、血生化检查,行HRA系统检测,按照HRA系统描述可将检测人群分为血脂未见异常组及血脂水平变化组。 结果 (1) HRA描述的血脂水平变化组相对应的血脂生化指标三酰甘油(TG)与低密度脂蛋白胆固醇(LDL-C)水平均高于血脂未见异常组,且差异有统计学意义(P<0.05)。(2)不同HRA分组,血脂水平变化组的高三酰甘油血症(高TG)、高胆固醇血症(高TC)、高低密度脂蛋白胆固醇血症(高LDL-C)、低高密度脂蛋白胆固醇血症(低HDL-C)患病率均明显高于血脂正常组,两组的高三酰甘油血症(高TG)、高低密度脂蛋白胆固醇血症(高LDL-C)的患病率比较差异有统计学意义(P<0.05)。(3)HRA系统对血脂高三酰甘油血症(高TG)的敏感性达75.44%,对高低密度脂蛋白胆固醇血症(高LDL-C)的敏感性达74.80%。 结论 HRA系统可作为健康人群血脂功能异常早期风险筛查的工具。
     

Acute management of exposure to liquid ammonia

Ammonia injury is an uncommon injury, but it is associated with high morbidity and mortality. This case report demonstrates the pathophysiology and treatment of both cutaneous burn wounds and inhalation injury caused by ammonia. Frequent bronchoscopy was used to attempt to avoid intubation and its associated morbidity. The patient remained extubated, but later he required skin grafts to close his wounds after healing of his pulmonary injury. A review of the management of inhalation injury is also discussed. Ammonia injury can cause a severe inhalation injury. Bronchoscopy can be a useful tool to avoid intubation.     

Recovery of chondrocyte metabolic activity after thermal exposure

BACKGROUND: The relationship between temperature elevation and thermal exposure time during thermal chondroplasty has implications for cell viability and subsequent articular cartilage function. PURPOSE: To characterize cartilage metabolic changes after exposure to thermal stress and to determine whether changes seen acutely are reversible. STUDY DESIGN: Controlled laboratory study. METHODS: Human cartilage was exposed to a 45 degrees, 50 degrees, or 55 degrees C bath for up to 3 minutes. Untreated control specimens were analyzed with each group. Viability and metabolic capability of treated and untreated specimens were evaluated immediately or 1 week after thermal stress by using methylthiotetrazole conversion, (3)H-serine incorporation into protein, and (35)S-sulfate incorporation into newly synthesized proteoglycan. RESULTS: Nonarthritic and arthritic articular cartilage metabolic activity declined with increasing thermal exposure. Articular cartilage displayed a recovery from thermal stress after exposure to the 50 degrees C but not the 55 degrees C bath. Arthritic cartilage displayed increased sensitivity with higher temperatures. CONCLUSIONS: Understanding of the increased sensitivity to thermal stress of arthritic articular cartilage may be helpful in thermally based treatments. Clinical Relevance: Further correlation with the temperatures attained during thermal chondroplasty will be necessary to confirm the clinical relevance of these in vitro observations to the use of radiofrequency energy devices to treat partial-thickness chondral lesions.     

Usefulness of a latex agglutination assay for FDP D-dimer to demonstrate the presence of postmortem blood

D-dimer, a specific fragment resulting from degradation of cross-linked fibrin, is an essential marker for the diagnosis of disseminated intravascular coagulation (DIC). Rapid assay for D-dimer using monoclonal antibody coated-latex particles might be useful for discriminating between postmortem and antemortem blood in bloodstains. We tried to detect D-dimer in nine postmortem blood samples by the rapid latex agglutination assay and to quantify them automatically using the latex photometric immunoassay system. The results showed that all samples were positive and that their amounts of D-dimer were 335–2,800 g/ml (the normal blood level, <1 g/ml; the pathogenic blood level with DIC, 1–100 g/ml). Next, nine stains made of postmortem blood were examined by the rapid latex agglutination assay. The result showed that only one case (D-dimer 335 g/ml blood) showed weak positive while the others (D-dimer 600–2,800 g/ml blood) were positive. The present study indicates that the latex agglutination assay for D-dimer can be useful to demonstrate the presence of postmortem blood.     

Evaluation of latex agglutination tests for fibrin-fibrinogen degradation products in the forensic identification of menstrual blood

The identification of menstrual blood is important when discriminating menstruation from vaginal trauma in sexual assault cases. The aim of this study was to evaluate two fibrin–fibrinogen degradation product (FDP)-latex agglutination test kits, FDPL® Test (FDP-L) and FDP Plasma “RD” (FDP-P), for their ability to forensically identify menstrual blood. Sensitivity and specificity of the two kits were compared for menstrual blood and various body fluids, and the sensitivity of the FDP-latex agglutination test kit was also compared with that of an immunochromatographic test for human hemoglobin. The robustness of the FDP-latex agglutination test was compared with that of gene expression analysis of menstrual blood specific markers. The FDP-L kit was more sensitive than the FDP-P kit, but it cross-reacted with peripheral bloodstains from healthy volunteers. The FDP-P kit was specific for menstrual blood, with the exception of postmortem blood samples, and was not affected by other body fluids. In an FDP-negative menstrual blood sample, the sensitivity of human hemoglobin detection was lower than for FDP-positive samples and peripheral blood stains, suggesting that determination of human hemoglobin could be useful in interpreting negative results in the FDP-latex agglutination test. In menstrual blood samples incubated in wet conditions, FDP was found to be a robust marker in the identification of menstrual blood compared with mRNA markers. FDP-P testing was shown to be a suitable and highly efficient rapid screening test for the laboratory identification of menstrual blood.     

The behavioral effects of anticholinesterase insult following exposure to different environmental temperatures

This study evaluates soman toxicity via a number of behavioral tasks after an 8-h exposure to one of five thermal stress conditions (-1,7,15,23, or 31 degrees C at 80 +/- 5% RH). Animals were removed from the environmental chamber, injected with soman (0-160 micrograms X kg-1), and tested 30 min post-injection. The test battery included: motor activity, grip strength, core temperature, sensitivity to heat, effects on memory and learning, and a subjective rating of the animal's state of health. A significant thermal stress/soman interaction was observed for all measures. This interaction was seen as a shift of the soman dose-response functions to the right for the higher temperature groups, i.e., the lower the stress temperature, the greater the susceptibility to soman. For example, the ED50 for the activity measure was 38 micrograms X kg-1 for the -1 degree C exposure group and 94 micrograms X kg-1 for the 31 degrees C group. The thermal stress influence on soman toxicity may be a function of previous motor activity.     

The use of thoracic impedance for determining thoracic blood volume changes in man

In these studies, strong inferential evidence is provided which suggests that thoracic impedance provides reliable estimates of thoracic blood volume changes in man. There were 24 volunteers studied in 4 different experiments. The results of these studies are as follows: Impedance derived blood volume changes in the calf of man correlate closely with standard estimates of calf blood volume changes made with strain gauge plethysmography. There is a close linear relationship between the increase of thoracic impedance and the increase of calf blood volume during head-up tilt. Volunteers who develop syncope during head-up tilt (presumably due to excessive decreases of central blood volume) demonstrate exaggerated increases of thoracic impedance. Decreases in central venous pressure produced by lower body negative pressure are significantly correlated to thoracic impedance increases.     

The use and control of heel prick blood samples

The human body is assuming new meanings and value. When tissue, such as hair, blood and saliva is subjected to DNA analysis, detailed intimate information can be revealed about a person that may predict information about behavioural traits and future disorders. Such genetic information may lead to the development of beneficial therapeutic treatments, but it may also lead to employment or insurance discrimination. Human tissue is commonly used by law enforcement agencies to detect perpetrators of crimes and to identify corpses. There are many sources of such tissue samples. One is from samples routinely collected from newborn babies for a test known as the "Guthrie test" or heel prick test. At about two days of age the child's heel is pricked and the resultant drops of blood are applied to filter paper attached to a test card. This is dried and analysed and, in New Zealand, the cards are stored indefinitely. The potential range of research purposes using such blood samples is increasing, and expanding markets have increased their value. This paper considers the status of the samples in light of recent developments in New Zealand and suggests appropriate approaches for retention and further use of the samples, or third party access to them.     

The use of early postoperative MR in detecting residual juvenile cerebellar pilocytic astrocytoma.

PURPOSEWe compared visibility of residual juvenile cerebellar pilocytic astrocytomas (JPAs) on early postoperative and follow-up MR studies to determine whether early postoperative MR imaging has a valid role as a baseline study.METHODSWe reviewed the MR images of 21 consecutive children who had undergone resection of cerebellar JPA. The diagnosis of residual tumor was made on the basis of nodular enhancement that corresponded to enhancing tumor on the preoperative MR studies and/or nonenhancing nodular T2 signal that corresponded to nonenhancing tumor. Because no patient received chemotherapy or radiation therapy, abnormal T2 signal or enhancement on the early postoperative study that resolved on the follow-up study was presumed to be due to peritumoral edema and/or surgical manipulation. Nodular T2 signal and/or enhancement in the tumor bed not seen on the initial postoperative MR study but present on the subsequent MR study and unchanged on serial follow-up MR studies was presumed to represent residual tumor rather than tumor that had recurred.RESULTSCompared with follow-up studies, the initial postoperative MR images were true-positive for residual tumor in six patients, false-positive in five, equivocal for residual tumor in four, true-negative in five, and false-negative in one. Residual tumor did not consistently enhance, and peritumoral edema and changes resulting from surgical manipulation tended to mask or simulate residual tumor.CONCLUSIONEarly postoperative MR imaging is not accurate in differentiating residual JPA from postoperative changes, and the role of early postoperative MR imaging as a baseline study for comparison with further studies is questionable.     

凝血功能检测对不同年龄段严重烧伤患者的诊治价值

 目的 分析严重烧伤患者检测凝血功能的价值。方法 收集本院严重烧伤84例, 根据年龄分成老年组、中年组和青少儿组;选择健康体检人群25名为健康对照组。观察各组患者在不同时间内各参数的变化情况。结果 老年组入院第1天纤维蛋白原(fibrinogen, FIB)明显升高, 最高达(4.74±1.69)g/L, 与对照组比较差异有统计学意义(P<0.01);凝血酶原时间(prothrombin time , PT)与对照组比较差异无统计学意义;活化部分凝血活酶时间(activated partial thromboplastin time, APTT)和凝血酶时间(thrombin time, TT)在入院第7天升高明显, 达(20.22±6.59)s与对照组比较, 差异有统计学意义(P<0.01)。中年组凝血4项结果 与对照组比较无明显差异, 仅APTT有轻度上升趋势, 但无统计学意义。青少儿组APTT与对照组比较明显升高(P<0.01), 差异有统计学意义(P<0.05);PT与对照组比较偏低, 差异无统计学意义。结论 检测凝血功能对严重烧伤患者的诊治有重要指导价值。