Fatal Insulin Overdoses: Case Report and Update on Testing Methodology.

Suicidal insulin overdoses are an under-recognized and uncommon cause of death, often relying on scene and nonspecific autopsy findings. Here, we present a case report of a fatal exogenous insulin overdose in a patient with type 1 diabetes. In our case, there were no contributory autopsy findings; however, serum analog aspart insulin levels were c. 10× the predicted therapeutic upper limit (4000, reference 6.6-55 uU/mL), which correlated with scene findings. This was specifically determined by a newly developed immunocapture liquid chromatography-tandem mass spectrometry assay, able to discriminate between various synthetic insulin analogs. Total insulin levels by immunoassay were highly elevated on the Siemens Advia Centaur, but not the Roche platforms (4741 vs. 5.2 uU/mL, respectively), showing variable sensitivity of detection within the same analog depending on assay. We discuss the prevalence and features to look for at autopsy in these types of cases. Additionally, analytical options for testing insulin levels, including new methodologies, guidance on collection of samples, as well as an outline of available historical reference range data are discussed.

Child abuse-related homicides in New Mexico: a 6-year retrospective review.

We retrospectively reviewed autopsy records at a statewide medical examiner's office in order to identify and characterize deaths due to child abuse. In a 6-year period in New Mexico, the medical examiner investigated 45 deaths determined to be child abuse-related. Decedents were predominantly male (68.9%), Hispanic White (53.3%), and all were 5 years of age or younger, with a median age of 1 year. Head injuries were the most common cause of death (44.4%), followed by battered baby syndrome (15.6%). Relatives were involved as alleged perpetrators in 80% of the cases, with the father most often implicated (36.1% of cases), and 88.9% of child abuse injuries resulting in death occurred in the family's residence. Toxicology was positive in 26.7% of cases, but only two cases had substances of abuse present. Information on risk factors such as prematurity, parental age, and history of abuse was also collected.

Traumatic vertebral artery injury: detailed clinicopathologic and morphometric analysis of 6 cases.

Traumatic vertebral artery injury is frequently fatal from what may often be mild trauma to the head and neck. Detailed examination of vertebral arteries is not frequently undertaken at autopsy: the structural and histologic changes that may be relevant to the development of the injury are not well known. We sampled vertebral arteries bilaterally from 6 forensic autopsies (age = 26-50 years; 3 of 6 suffered from alcohol toxicity) with documented intradural vertebral artery injuries, and 4 nonvertebral-artery-injury-related autopsies (age = 19-70 years). Intradural, dural, and extradural components from each artery were submitted for paraffin-embedded tissue processing. Multiple serial sections and special stains (hematoxylin and eosin, alcian blue pH 2.5, reticulin, Congo red) were independently examined by 2 pathologists. All 6 of 6 injured samples and 4 of 4 control samples showed degenerative changes (intimal fibrosis, focal disruption of the internal elastic lamina, and medial calcification). However, microscopic adventitial hemorrhages were only observed around peripheral nerves adjacent to the injured samples. These may be due to tracking of blood along perineural loose connective tissue regions of reduced resistance, and may be a useful finding that points to underlying vertebral artery injury. Thus, careful dissection and gross and microscopic, examination of the vertebral arteries, with particular attention to the intracranial segments, is recommended in all cases of fatal traumatic head and neck injuries.

Hepatic potential of bone marrow stromal cells: development of in vitro co-culture and intra-portal transplantation models.

Bone marrow comprises heterogeneous cell populations and is thought to contain certain progenitors with the ability to differentiate into multiple mesenchymal cell lineages. To identify any differentiation plasticity of adult bone marrow stromal cells (BMSCs) into hepatocyte-like phenotypes, we developed a co-culture model with damaged liver tissue and an animal model of engraftment in cirrhotic liver via intra-portal transplantation. After 10 days of co-culture with injured liver tissues, BMSC expressed specific markers for hepatocytes by RT-PCR and Western blot. The two animal models for liver injury employed used carbon tetrachloride (CCl4) induction or bile duct ligation. For tracing BMSC resident in the liver after intra-portal transplantation, green fluorescent protein (GFP)-positive BMSCs or in situ hybridization of Y-chromosome Sry gene in male BMSC were used in a cross-sex transplantation model. Expression of hepatocyte-specific markers in recipients' liver tissues was determined by fluorescence immunohistochemistry. Our findings demonstrated that about 16% parenchyma cells were GFP-positive cells derived from infused BMSCs, and expression of albumin was detected in these cells in engrafted liver tissues. In conclusion, BMSCs exhibited hepatocyte-like phenotypes after co-cultivation with liver tissue and transplanted into the injured liver. The presented evidence indicated the trans differentiation potential of BMSC developing to the hepatocytes.

Proteomic identification of Ku70/Ku80 autoantigen recognized by monoclonal antibody against hepatocellular carcinoma.

A murine monoclonal antibody (mAb), CLD3 (IgG(1),kappa), was generated against hepatocellular carcinoma (HCC). Both immunofluorescence and immunohistochemical assays indicated the reactivity of CLD3 mAb localized at the nucleus and/or cytoplasm of tumorigenic HCC cell lines as well as in liver cancer tissues. By immunoprecipitation and using the matrix-assisted laser desorption/ionization-time of flight mass spectrometry approach, the antigenic specificity of CLD3 was determined to be heterodimeric Ku70 and Ku80 autoantigen, which was confirmed by Western blotting.