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821.
This case represents unusual findings of elevated bupivacaine and tryptase concentrations following local anesthetic, bupivacaine, administered as a scalene nerve block for elective rotator cuff repair surgery. Following bupivacaine injection, the patient exhibited almost immediate seizure activity, bradycardia, and cardiac arrest. Resuscitative efforts including cardiopulmonary bypass restored a cardiac rhythm. However, the clinical medical status of the patient progressively declined and he died 7 h following administration of the local anesthetic. Autopsy revealed several abnormalities of the heart including cardiomegaly, myocardial bridging, and lipomatous hypertrophy of the intraatrial septum, which may have contributed to bradycardia and arrhythmia. Postmortem toxicology results revealed elevated bupivacaine and tryptase concentrations. Elevated postmortem bupivacaine concentrations 7 h following administration and abrupt onset of seizures indicate unintentional intravascular injection instead of nerve and tissue infiltration. An elevated postmortem tryptase concentration points to the possibility of a hypersensitivity reaction to bupivacaine.  相似文献   
822.
Abstract:  With <100 pg of template DNA, routine short tandem repeat (STR) analysis often fails, resulting in no or partial profiles and increased stochastic effects. To overcome this, some have investigated preamplification methods that include the addition of proofreading enzymes to the PCR cocktail. This project sought to determine whether adding proofreading polymerases directly in the STR amplification mixture would improve the reaction when little template DNA is available. Platinum Taq High Fidelity and GeneAmp High Fidelity were tested in Profiler Plus? STR reactions alone and in combination with AmpliTaq® Gold. All reactions included the additional step of a post‐PCR purification step. With both pristine low template DNA and casework samples, the addition of these polymerases resulted in comparable or no improvement in the STR amplification signal. Further, stochastic effects and artifacts were observed equally across all enzyme conditions. Based on these studies, the addition of these proofreading enzymes to a multiplex STR amplification is not recommended for low template DNA work.  相似文献   
823.
Canines are usually used in anthropological and forensic sciences for sex and age determination. The best methods to estimate age are based on secondary dentine apposition, evaluated from periapical X-rays. The aim of this study was to propose a new method of sex and age estimation using 3D models to obtain more precise predictions using tooth volumes. Fifty-eight dental CT scans of patients aged 14-74 with a well-balanced sex ratio composed the sample. One hundred and thirty-three healthy canines were modeled (Mimics 12.0). The sample was divided into a training sample and a validation sample. An age formula was determined using the "pulp volume/tooth volume" ratio. Sex prediction was adjusted with total volumes. Applying the equations to the validation sample, no significant difference was found between the real and predicted ages, and 100% of the sex predictions were correct. This preliminary study gives interesting results, and this method is worth being tested on a larger data sample.  相似文献   
824.
This case concerns an unusual suicidal plastic bag suffocation. An elderly white man was found dead and partially disrobed in his apartment lying supine on a sofa with a plastic bag closed by a rope over the head and the upper and lower extremities tightly tied with two other ropes, the end of both arranged into slipknots (self-rescue mechanism). Police investigations found no pornography in the apartment, and circumstantial data alleged no psychiatric disorders or suicidal intentions. The autopsy excluded signs of struggle and sexual intercourse as well as any type of injury or physical illness. Chemical analyses on the peripheral blood excluded acute drugs and/or alcohol intoxication. A differential diagnosis of the manner of death was performed, including scenarios of accidental autoerotic asphyxiation, homicide during either sexual activity or ritualistic, elderly suicide. The collected data most strongly supported the hypothesis of a suicidal asphyxiation simulating homicide to devolve a life insurance to the victim's sons because of economic difficulties.  相似文献   
825.
Abstract: This study assesses the predictive value of anterior sacral curvature for sex estimation from skeletonized remains. Sacra from a sample of 125 American adults of known age and sex were examined. Nine measurements describing anterior sacral curvature were used in the analysis. Statistical treatment of the data included univariate statistics and discriminant function analysis for sex classification. A bootstrap validation method was employed to assess the classification error rates. Sacral curvature was significantly greater in men than in women at the level of the S2–S3 and S3–S4 articulations (p < 0.05). Correct classification estimates for the discriminant function range from 66–72%. Although sexually dimorphic, metric observations of sacral curvature are not as reliable at predicting sex as other skeletal elements. Anterior sacral curvature should only be used for sex estimation in the absence of other, more reliable, indicators.  相似文献   
826.
Abstract: Pyrodex ® and Triple Seven ® are black powder substitutes that often find use as fillers in improvised explosive devices, such as pipe bombs. These propellants have essentially the same overall appearance and oxidizers, but different fuels. For example, Pyrodex ® contains sulfur, sodium benzoate, and dicyandiamide (DCDA), whereas Triple Seven ® lacks sulfur but also contains 3‐nitrobenzoic acid. In this method, intact particles and postblast solid residues were reacted with bis(trimethylsilyl)trifluoroacetamide + 1% trimethylchlorosilane in acetonitrile for 30 min at 60°C. The resultant trimethylsilyl derivatives of the organic fuels were then analyzed by gas chromatography–mass spectrometry. Each derivative was clearly resolved from other components, and high‐quality mass spectra were obtained. In addition, characteristic fragments resulting from loss of a methyl radical from the molecular ion (m/z 163 for sulfur, m/z 171 for DCDA, m/z 179 for benzoic acid, and m/z 224 for nitrobenzoic acid) were able to be monitored.  相似文献   
827.
Laser detection of latent fingerprints on a white paper has been performed, previously. Ultraviolet fluorescence from various kinds of printer toner and ink used for home printers were measured to study fluorescence imaging of fingerprints on a color-printed white paper. The experimental system consisted of a nanosecond pulsed tunable laser and a cooled CCD camera. Excitation wavelengths are 230 and 280 nm. Fourteen printers consisting of three color laser printers, three color inkjet printers, five monochrome laser printers, two monochrome copy machines, and a color copy machine were tested. Toner and ink of most printers exhibited fluorescence in the region from 360 to 550 nm. In most cases, clear fluorescence images were obtained by time-resolved imaging with a band-pass filter and 280-nm excitation. However for toners from laser color printers that showed strong fluorescence, better results were obtained with 230-nm excitation. Latent fingerprints on a photograph page and a black-character page of a newspaper were also imaged.  相似文献   
828.
Measurement of the amount of fat in femoral bone marrow can provide a quantitative assessment of the nutritional status of an individual animal. An analytical method is presented for quantitating the percent fat in bone marrow from three domestic species: bovine, canine, and equine. In this procedure, fat is extracted from bone marrow using pentane, and the percent fat recovered is determined gravimetrically. Based on analyses from adult animals (normal body condition scores), the average percentage of fat in the bone marrow was >80%. In cases in which animals have been diagnosed as emaciated or exhibit serous atrophy of fat (body scores of 1 or 2), the femoral bone marrow fat was less than 20%. In domestic animals, bone marrow fat analysis can be a useful, quantitative measure that, when used in conjunction with all other data available, can support a diagnosis of starvation or malnutrition.  相似文献   
829.
A well-documented case of so-called Spontaneous Human Combustion is reported. Review of the literature shows that these strange observations have been reported since the 17th century, even in famous novels. There are several main features that may lead to help the diagnosis: the vicinity of the body is intact or nearly intact, some parts of the body are turned into ashes (usually the middle third of the body), whereas other parts are intact or nearly intact, burning of the body usually occurs postmortem, the cause of death is usually natural, there is often (but not always) high concentrations of blood alcohol, there is a source of heat near the body. It is indispensable to rule out a homicide by the examination of the body in situ, the autopsy, the toxicological and histopathological samples, the arson assessment, and a thorough police inquiry.  相似文献   
830.
Abstract: Amussat’s sign is typically a transverse laceration of the intimal layer of carotid arteries described in cases of hanging. Subtotal laceration of the carotid artery is not strictly specific for hanging and can be also caused by blunt neck trauma, extreme overstretching, or whiplash‐injuries. In a prospective autopsy study of 178 cases of hanging, Amussat’s sign was found in 29 cases (a relative frequency of 16.1%). A statistically significant association between the occurrence of tears in the intimal layer of carotid arteries and the victims’ age was discovered in the cases studied (the frequency increased with age; p < 0.05). The occurrence of Amussat’s sign was independent of gender, weight, completeness of the victim’s body suspension, and position of the ligature knot on the neck. The study demonstrates the fact that the most probable cause of Amussat’s sign is a combination of direct compression of the artery by the rope and indirect stretching because of the gravitational drag produced by the weight of the body.  相似文献   
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