Oak Trail Shores, TX, United States
Oak Trail Shores, TX, United States

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Guale F.,Harris County Institute of Forensic science | Shahreza S.,Harris County Institute of Forensic science | Walterscheid J.P.,Harris County Institute of Forensic science | Chen H.-H.,Harris County Institute of Forensic science | And 3 more authors.
Journal of Analytical Toxicology | Year: 2013

Liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) analysis provides an expansive technique for identifying many known and unknown analytes. This study developed a screening method that utilizes automated solid-phase extraction to purify a wide array of analytes involving stimulants, benzodiazepines, opiates, muscle relaxants, hypnotics, antihistamines, antidepressants and newer synthetic "Spice/K2" cannabinoids and cathinone "bath salt" designer drugs. The extract was applied to LC-TOF-MS analysis, implementing a 13 min chromatography gradient with mobile phases of ammonium formate and methanol using positive mode electrospray. Several common drugs and metabolites can share the same mass and chemical formula among unrelated compounds, but they are structurally different. In this method, the LC-TOF-MS was able to resolve many isobaric compounds by accurate mass correlation within 15 ppm mass units and a narrow retention time interval of less than 10 s of separation. Drug recovery yields varied among spiked compounds, but resulted in overall robust area counts to deliver an average match score of 86 when compared to the retention time and mass of authentic standards. In summary, this method represents a rapid, enhanced screen for blood and urine specimens in postmortem, driving under the influence, and drug facilitated sexual assault forensic toxicology casework. © The Author [2012]. Published by Oxford University Press. All rights reserved.


Kelly A.T.,Harris County Institute of Forensic science | Mozayani A.,Harris County Institute of Forensic science
Journal of Pharmacy Practice | Year: 2012

Ethanol analysis is the most commonly carried out drug testing in a forensic toxicology laboratory. Determination of blood alcohol concentration (BAC) is needed in a multitude of situations, including in postmortem analysis, driving under the influence (DUI) and drug-facilitated sexual assault (DFSA) cases, workplace drug monitoring, and probation investigations. These analyses are carried out by direct measurement of ethanol concentrations as well as of metabolic by-products, such as ethyl glucuronide (EtG) and ethyl sulfate (EtS). This review article will discuss pharmacokinetics, including absorption, distribution, and elimination of ethanol, methods for the detection of ethanol, the effect of ethanol on human performance, the role of alcohol in injuries and fatalities, and information regarding the interactions that may occur between alcohol and other drugs. Finally, an explanation will be given on how to interpret al.ohol levels as well as the extrapolation and calculation of blood alcohol levels at times prior to sample collection. © The Author(s) 2012.


Pinto D.C.,Harris County Institute of Forensic science | Haden-Pinneri K.,Harris County Institute of Forensic science | Love J.C.,Harris County Institute of Forensic science
Journal of Forensic Sciences | Year: 2013

The purpose of this study was to identify and compare patterns of trauma associated with AutoPulse® CPR and manual CPR. Finalized autopsy records from 175 decedents brought to the Harris County Institute of Forensic Sciences were reviewed, 87 received manual-only CPR, and 88 received AutoPulse® CPR (in combination with manual CPR as per standard protocol). The characteristic pattern observed in manual-only CPR use included a high frequency of anterior rib fractures, sternal fractures, and midline chest abrasions along the sternum. The characteristic pattern observed in AutoPulse® CPR use included a high frequency of posterior rib fractures, skin abrasions located along the anterolateral chest and shoulder, vertebral fractures, and a few cases of visceral injuries including liver lacerations, splenic lacerations, and hemoperitoneum. Knowledge of the AutoPulse® CPR injury pattern can help forensic pathologists differentiate therapeutic from inflicted injuries and therefore avoid an erroneous assessment of cause and manner of death. © 2013 American Academy of Forensic Sciences.


Love J.C.,Harris County Institute of Forensic science | Derrick S.M.,Harris County Institute of Forensic science | Wiersema J.M.,Harris County Institute of Forensic science | Peters C.,University of Houston
Journal of Forensic Sciences | Year: 2012

This study was designed to establish the potential error rate associated with the generally accepted method of tool mark analysis of cut marks in costal cartilage. Three knives with different blade types were used to make experimental cut marks in costal cartilage of pigs. Each cut surface was cast, and each cast was examined by three analysts working independently. The presence of striations, regularity of striations, and presence of a primary and secondary striation pattern were recorded for each cast. The distance between each striation was measured. The results showed that striations were not consistently impressed on the cut surface by the blade's cutting edge. Also, blade type classification by the presence or absence of striations led to a 65% misclassification rate. Use of the classification tree and cross-validation methods and inclusion of the mean interstriation distance decreased the error rate to c. 50%. © 2011 American Academy of Forensic Sciences.


Walterscheid J.P.,Harris County Institute of Forensic science | Phillips G.T.,Harris County Institute of Forensic science | Lopez A.E.,Harris County Institute of Forensic science | Gonsoulin M.L.,Harris County Institute of Forensic science | And 2 more authors.
American Journal of Forensic Medicine and Pathology | Year: 2014

The research compound 25I-NBOMe, also known as CIMBI-5 or INBMeO, was created in academic laboratories as a potent serotonin 2A receptor agonist. Because of its high affinity and ambiguous legal status, recreational drug enthusiasts have used this compound as a powerful alternative to other hallucinogenic drugs such as lysergic acid diethylamide. We report 2 deaths after 25I-NBOMe ingestion by decedents who attended separate "rave" parties. The first case involved a 21-year-old male who admitted taking "acid" to his friend. A sudden violent rage caused him to flail about, and he subsequently became unresponsive. The postmortem examination revealed numerous external injuries that were consistent with physical aggression. The second case involved a 15-year-old female who was socializing outside a rave party, became ill, and rapidly deteriorated as her friend transported her to the hospital. The postmortem assessment was similar to the first case in that external contusions featured prominently. Comprehensive toxicology screens in both cases revealed only evidence of marijuana use. A deeper analysis using time-of-flight mass spectrometry revealed the presence of 25I-NBOMe, which was further confirmed by tandem-mass spectrometry. The behavior and injuries in these cases reveal a consistent pattern preceding fatal 25I-NBOMe toxicity. Copyright © 2014 Lippincott Williams & Wilkins.


Sanford M.R.,Harris County Institute of Forensic science | Whitworth T.L.,Washington State University | Phatak D.R.,Harris County Institute of Forensic science
Journal of Medical Entomology | Year: 2014

The infestation of human or animal tissues by fly larvae has been given distinctive terminology depending on the timing and location of colonization. Wounds and orifices colonized by Diptera in a living human or animal are typically referred to as myiasis. When the colonization occurs after death, it is referred to as postmortem colonization and can be used to estimate the minimum postmortem interval. What happens when the human, as in the case presented here, has a necrotic limb while the human remains alive, at least for a short period of time? The case presented here documents perimortem wound colonization by Lucilia eximia (Wiedemann) and Chrysomya rufifacies (Macquart) and the considerations for approximating development temperatures and estimating the time of colonization (TOC). This represents the first record of L. eximia in human myiasis in the United States and the first record of the co-occurrence of L. eximia and C. rufifacies in human myiasis in the United States. The TOC was estimated using both ambient and body temperature. Insect colonization before death complicates the estimation of TOC and minimum postmortem interval and illustrates the problem of temperature approximation in forensic entomology casework. © 2014 Entomological Society of America.


Samms W.C.,Harris County Institute of Forensic science | Jiang Y.J.,Harris County Institute of Forensic science | Dixon M.D.,Harris County Institute of Forensic science | Houck S.S.,Harris County Institute of Forensic science | Mozayani A.,Harris County Institute of Forensic science
Journal of Forensic Sciences | Year: 2011

The high prevalence of alprazolam abuse translates to an increased workload for crime laboratories in characterizing seized tablets. These tablets may originate as diverted pharmaceuticals or counterfeited mimics, so efficient analytical techniques should provide confirmatory data while minimizing destruction of evidence. We offer the first report of a validated forensic method for confirming alprazolam tablets by direct analysis in real time-time of flight (DART-TOF) mass spectrometric analysis. This technique provides rapid identification of target analytes with minimal sample preparation, allowing direct analysis in the atmospheric sample gap. Selectivity is achieved through high resolution and mass accuracy, unique ion fragments, and chlorine isotopic ratios. This method utilizes fragmentation in two separate voltage functions to observe the alprazolam pseudo molecular ion at 309.09070 using 40V and major ion fragments of 281.07197 and 205.07657 at 120V. These parameters allow our laboratory to confirm alprazolam tablets efficiently, without compromising quality forensic standards. 2011 American Academy of Forensic Sciences.


Schlecht S.H.,University of Michigan | Pinto D.C.,Harris County Institute of Forensic science | Agnew A.M.,Ohio State University | Stout S.D.,Ohio State University
American Journal of Physical Anthropology | Year: 2012

The intricate link between load environment and skeletal health is exemplified by the severe osteopenia that accompanies prolonged periods of immobilization, frequently referred to as disuse osteoporosis. Investigating the effects disuse has on the structural properties of bone provides a unique opportunity to better understand how mechanical loads influence the adaptation and maintenance of skeletal tissue. Here, we report results from an examination of multiple indicators of bone metabolism (e.g., mean osteon density, mean osteon size, bone mass, and bone area distribution) within the major long bones of individuals with distinct activity level differences. Results are based on a sample comprising two subjects that suffered from long-term quadriplegia and 28 individuals of comparable age that had full limb mobility. Although limited in sample size, our findings suggest bones associated with long-term disuse have lower osteon densities and larger osteon areas compared to individuals of normal mobility, reflecting dramatically lower remodeling rates potentially related to reduced strain levels. Moreover, immobilized skeletal elements demonstrate a reduced percentage of cortical area present resulting from endosteal resorption. Differences between mobility groups in the percentage of cortical area present and bone distribution of all skeletal elements, suggests bone modeling activity is negligible in the unloaded adult skeleton. Additional histomorphometric comparisons reveal potential intraskeletal differences in bone turnover rates suggesting remodeling rates are highest within the humeri and femora. Addition of more immobilized individuals in the future will allow for quantitative statistical analyses and greater consideration of human variation within and between individuals. Am J Phys Anthropol 2012. © 2012 Wiley Periodicals, Inc. Copyright © 2012 Wiley Periodicals, Inc.


Patel N.R.,Baylor College of Medicine | Anzalone M.L.,Harris County Institute of Forensic science | Buja L.M.,University of Texas Health Science Center at Houston | Elghetany M.T.,Baylor College of Medicine | Elghetany M.T.,Texas Childrens Hospital
Archives of Pathology and Laboratory Medicine | Year: 2014

Immunoglobulin G4-related disease (IgG4-RD) is a systemic disorder characterized by multiorgan fibrosis with IgG4-producing plasma cells, increased IgG4 serum concentration, and responsiveness to steroid therapy. Involvement of the pancreas, salivary glands, orbit, aorta, and other sites has been well documented in the literature; however, there have been limited reports of cases involving the coronary arteries. We report the case of a 53-year-old Hispanic man who was brought to the emergency center and diagnosed with sudden cardiac death. Autopsy was subsequently performed, revealing multiorgan involvement by IgG4-RD, including involvement of the coronary arteries. The inflammation and fibrosis, in combination with concomitant atherosclerotic disease, resulted in severe stenosis of the coronary arteries. Two of the coronary arteries were further occluded by thrombosis. These factors led to cardiac hypoperfusion, myocardial infarction and, ultimately, sudden cardiac death. Fatal involvement of the coronary arteries has not been previously reported, raising a new concern for a severe complication of IgG4-RD.


Sanford M.R.,Harris County Institute of Forensic science
Forensic Science International | Year: 2015

Domestic pets are commonly found in the homes of decedents whose deaths are investigated by a medical examiner or coroner. When these pets become trapped with a decomposing decedent they may resort to feeding on the body or succumb to starvation and/or dehydration and begin to decompose as well. In this case report photographic documentation of cases involving pets and decedents were examined from 2009 through the beginning of 2014. This photo review indicated that in many cases the pets were cats and dogs that were trapped with the decedent, died and were discovered in a moderate (bloat to active decay) state of decomposition. In addition three cases involving decomposing humans and their decomposing pets are described as they were processed for time of insect colonization by forensic entomological approach. Differences in timing and species colonizing the human and animal bodies were noted as was the potential for the human or animal derived specimens to contaminate one another at the scene. © 2014 Elsevier Ireland Ltd.

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