H2O2诱导PC12细胞凋亡前后miRNA的变化及探讨

目的用微小RNA(miRNA)基因芯片技术检测H2O2诱导凋亡的PC12细胞和正常PC12细胞miR-NA的表达谱差异。方法分别以不同浓度的H2O2处理PC12细胞12h,用MTT和流式细胞仪检测处理后细胞的生长活力和凋亡情况;分别提取A(0浓度H2O2处理组)和B(400nmol/LH2O2处理组)PC12细胞的miRNA做miRNA基因芯片检测。结果以A组作为对照,30、50、100、200、400nmol/L的H2O2处理的PC12细胞生存率分别为(92±9.80)%、(90±14.70)%、(80±13.85)%、(54±12.33)%、(22±7.35)%(P<0.01);0、30、50、100、200和400nmol/L的H2O2处理的PC12细胞早期凋亡率分别为2.6%、5.2%、7.2%、10.4%、16.6%、72.2%;在样品A中共筛选出68个有效表达的miRNA分子数据,在样品B中筛选出46个有效表达的miRNA分子数据,两者样品中均检测到有效表达的miRNA分子有39个,其中与样品A相比,在样品B中显著性下调表达的有6个。结论为脑缺血再灌注损伤中神经细胞凋亡的机制和治疗的研究提供了理论依据和新的研究思路。     

烧骨组织形态变化及DNA技术在个体识别中的应用

烧骨在火灾、焚尸、交通、爆炸等案件和事故的检材中具有特殊的地位。通过对不同条件焚烧下烧骨组织形态及DNA变化规律的研究,可为法医实践中烧骨的种属鉴定、性别及年龄判定提供准确的依据和标准,同时可利用残存的基因位点对烧骨残块进行个体识别和同一认定。烧骨DNA的提取方法及检测技术也在不断探索和改进。本文对烧骨在形态学、组织学和分子生物学水平研究进展以及烧骨评测的方法、技术进行概述,旨在为法医实践及进一步研究提供新的方法和思路。     

Nicotine and cotinine levels in body fluids of smokers who committed suicide

Cigarette smoking is associated with a higher risk for suicide. The present study was conducted on the hypothesis that suicide smokers show higher nicotine and cotinine levels in blood and urine than non-suicide smokers. We determined nicotine and cotinine levels in blood and urine of 87 deceased individuals (18 suicides and 69 non-suicides) by gas chromatography. The smoking rate was 77.8% for individuals who committed suicide and 42.0% for those who did not commit suicide. Average nicotine and cotinine levels in blood were significantly higher in the suicide smokers than in the non-suicide smokers (nicotine: 93.2+/-46.6 ng/ml versus 25.8+/-14.4 ng/ml, p<0.0001 and cotinine: 378+/-235 ng/ml versus 201+/-137 ng/ml, p<0.005). Average levels of urinary nicotine and cotinine were also significantly higher in the suicide smokers than in the non-suicide smokers (nicotine: 1980+/-2210 ng/ml versus 394+/-376 ng/ml, p<0.005 and cotinine: 1170+/-1330 ng/ml versus 414+/-290 ng/ml, p<0.05). Twenty-six decedents were intoxicated with alcohol, and they included 7 suicides (7 smokers) and 19 non-suicides (15 smokers). Our data suggest that cigarette smokers who commit suicide smoke more heavily than other cigarette smokers.     

"Volunteering by chance" to promote civic responsibility and civic engagement: does it work?

This study investigated the effectiveness of a program to promote civic responsibility and prevent antisocial behavior in a sample of Italian adolescents. Participants were 83 Italian male adolescents, attending the second year of high school (Mean age = 15.79; SD = 0.87). In order to test the efficacy of different strategies (in-classroom training and service activity in a voluntary organization) we divided students into two experimental groups--one classroom of students participated in both strategies (training + volunteering group) and another classroom only participated in the training (training only group)--and one control group. Process and efficacy evaluations were completed. Data were collected before and following the intervention. The process evaluation revealed that the program was highly accepted and appreciated by students. The efficacy evaluation revealed no intervention effects on civic responsibility. However, the training + volunteering group reported a significant decrease in antisocial behavior after the program. Thus, the program was effective in preventing antisocial behavior but not in promoting civic responsibility in our sample.     

Undiagnosed, untreated acute promyelocytic leukemia presenting as a suspicious sudden death

Acute promyelocytic leukemia (APL) is a subtype of acute myelogenous leukemia frequently associated with clotting abnormalities and severe hemorrhagic diathesis. The disease is associated with a high incidence of early fatal hemorrhage. We report the sudden death of a 40-year-old male without significant medical history in which foul play had been initially suspected. A thorough postmortem investigation performed on the decedent lead to the diagnosis of APL. Cause of death was a cerebellar hematoma. Underlying APL should be considered in the differential diagnosis when unexplained bleeding is encountered in a decedent. This case emphasizes the value of routinely collecting bone marrow during an autopsy to enable accurate testing and diagnosis.     

A case of sudden infant death due to a primary cardiac sarcoma

The case reported herein concerns the unexpected death of a 3-month-old female newborn who suddenly collapsed in her mother's arms and was dead on arrival at the hospital. The clinical histories of the baby and her parents were negative for symptoms or signs of illness, even those of cardiovascular origin. Furthermore, no clinical appearance of a pathologic status was noted by pediatricians after the birth until the last emergency recovery. The autopsy excluded external and internal signs of violence but revealed a large primary cardiac tumor arising from the free wall of the left ventricle, which had totally invaded the heart causing mitral valve deformation. Histological examination showed a low-grade sarcoma that completely infiltrated the myocardial tissue. The pathogenesis of this sudden infant death was postulated as being owing to a fatal ventricular fibrillation combined with a tumor-related restrictive cardiomyopathy obstructing left ventricular filling.     

Treating offenders with mental illness: a research synthesis

The purpose of this research synthesis was to examine treatment effects across studies of the service providers to offenders with mental illness. Meta-analytic techniques were applied to 26 empirical studies obtained from a review of 12,154 research documents. Outcomes of interest in this review included measures of both psychiatric and criminal functioning. Although meta-analytic results are based on a small sample of available studies, results suggest interventions with offenders with mental illness effectively reduced symptoms of distress, improving offender's ability to cope with their problems, and resulted in improved behavioral markers including institutional adjustment and behavioral functioning. Furthermore, interventions specifically designed to meet the psychiatric and criminal justice needs of offenders with mental illness have shown to produce significant reductions in psychiatric and criminal recidivism. Finally, this review highlighted admission policies and treatment strategies (e.g., use of homework), which produced the most positive benefits. Results of this research synthesis are directly relevant for service providers in both criminal justice and mental health systems (e.g., psychiatric hospitals) as well as community settings by informing treatment strategies for the first time, which are based on empirical evidence. In addition, the implications of these results to policy makers tasked with the responsibility of designating services for this special needs population are highlighted.     

Mentally challenged patients in a forensic hospital: a feasibility study concerning the executive functions of forensic patients with organic brain disorder, learning disability, or mental retardation

The past years have seen an increasing number of patients of lower intelligence or with organic brain disorder being committed into our forensic psychiatry. Our clinic has an ongoing scientific project to investigate the possibilities of reducing costs while at the same time guaranteeing adequate treatment and enforcement practice in forensic hospitals. This current project did not take these kinds of patients into consideration initially. This feasibility study is intended to examine if and to what extent these patients can be part of the scientific project. All patients of forensic psychiatry in Rostock (Mecklenburg-Western-Pomerania) with an IQ<80 (learning disorder) or a primary or secondary organic brain dysfunction that have been committed to the clinic since 2009 are included. These patients went through an extensive battery of neuropsychological tests. Furthermore, the treating psychotherapists had to rate the prognoses for criminal re-offending at discharge. Patients affected by lower intelligence or an organic brain dysfunction achieve lower results in neuropsychological testing than other patients participating in the main project. Nevertheless, participation in neuropsychological testing does not appear to overtax them. Future examination of the patients will be conducted to investigate to what extent certain therapeutic methods have been of noticeable benefit to this problematic group.     

Detection of hemorrhage source: The diagnostic value of post-mortem CT-angiography

The aim of this study was to compare the diagnostic value of post-mortem computed tomography angiography (PMCTA) to conventional, ante-mortem computed tomography (CT)-scan, CT-angiography (CTA) and digital subtraction angiography (DSA) in the detection and localization of the source of bleeding in cases of acute hemorrhage with fatal outcomes. The medical records and imaging scans of nine individuals who underwent a conventional, ante-mortem CT-scan, CTA or DSA and later died in the hospital as a result of an acute hemorrhage were reviewed. Post-mortem computed tomography angiography, using multi-phase post-mortem CTA, as well as medico-legal autopsies were performed. Localization accuracy of the bleeding was assessed by comparing the diagnostic findings of the different techniques. The results revealed that data from ante-mortem and post-mortem radiological examinations were similar, though the PMCTA showed a higher sensitivity for detecting the hemorrhage source than did ante-mortem radiological investigations. By comparing the results of PMCTA and conventional autopsy, much higher sensitivity was noted in PMCTA in identifying the source of the bleeding. In fact, the vessels involved were identified in eight out of nine cases using PMCTA and only in three cases through conventional autopsy. Our study showed that PMCTA, similar to clinical radiological investigations, is able to precisely identify lesions of arterial and/or venous vessels and thus determine the source of bleeding in cases of acute hemorrhages with fatal outcomes.     

Experimental study of the expansion dynamic of 9 mm Parabellum hollow point projectiles in ballistic gelatin

We study in this paper the expanding behaviour of hollow point 9 mm Parabellum projectiles (Hornady XTP(?) and Speer Gold Dot(?)). We defined a deformation rate that takes into account both the diameter increase and the length reduction. We plotted the behaviour of this parameter versus impact velocity (we refer to this curve as the expanding law). This expanding law has been plotted for different gelatin weight ratios and different gelatin block lengths. We completed our experiments with a set of high speed movies in order to correlate the deceleration to the state of expansion and size of the temporary cavity. Our results pointed out that full expansion is reached shortly after the projectile fully penetrates the gelatin. This result shows that the key point to accurately simulate human body interaction with a hollow point projectile is to accurately simulate the interface (skin, skull, clothes thoracic walls). Simulating accurately organs is only an issue if a quantitative comparison between penetration depths is required, but not if we only focus on the state of expansion of the projectile. By varying the gelatin parameters, we discovered that the expanding law exhibits a velocity threshold below which no expansion occurs, followed by a rather linear curve. The parameters of that expanding law (velocity threshold and line slope) vary with the gelatin parameters, but our quantitative results demonstrate that these parameters are not extremely critical. Finally, our experiments demonstrate that the knowledge of the expansion law can be a useful tool to investigate a gunshot in a human body with a semi-jacketed projectile, giving an estimation of the impact velocity and thus the shooting distance.