Ethylene glycol toxicity

Ethylene glycol (EG) poisoning continues to be common. This article covers the metabolism of ethylene glycol, clinical signs of toxicity and establishing a diagnosis of EG poisoning, as well as the emergency management of patients with suspected or identified ingestion and the associated prognosis.     

Retrospective Assessment of Exposure to Chemicals for a Microelectronics and Business Machine Manufacturing Facility

A retrospective exposure assessment was performed for use in a health outcomes study of a facility manufacturing circuit boards, business machines, and other equipment during the years 1969–2002. A matrix was developed identifying chemical use by department-year based on company-provided information. Use of six chemical agents (fiberglass, lead, methylene chloride, methyl chloroform, perchloroethylene, and trichloroethylene) and six chemical classes (acid-base, aromatic hydrocarbons, chlorinated hydrocarbons, other hydrocarbons, chlorofluorocarbons, and metals), and general (including unspecified) chemicals was identified. The matrix also contained an assignment for each department-year categorizing the potential for use of chemicals as negligible, intermittent/incidental, or routine. These department-based exposure matrix data were combined with work history data to provide duration of potential chemical use for workers. Negligible, intermittent/incidental or routine extent-of-chemical-use categories comprised 42.6%, 39.4%, and 17.9%, respectively, of total person-years of employment. Cumulative exposure scores were also developed, representing a relative measure of the cumulative extent of potential exposure to the six chemical agents, six chemical classes, and general (including unspecified) chemicals. Additionally, the study period was divided into manufacturing eras showing trends in chemical use, and showing that process use of trichloroethylene and methylene chloride ended in the mid-1980s and the mid-1990s, respectively. This approach may be useful in other assessments addressing a variety of chemicals, and with data constraints common to retrospective chemical exposure studies.     

The First Reported Case of Anti-Dob Causing an Acute Hemolytic Transfusion Reaction

The antibodies of the Dombrock blood group system have only rarely been encountered in transfusion practice, and anti-Do^b has not previously been implicated in an acute hemolytic transfusion reaction. We have encountered the first such case involving a chronically transfused black female with hemoglobin SS disease and multiple antibodies in her serum. During a previous admission for sickle cell crisis, the patient received 3 units of compatible blood with no untoward effects. Serum obtained 21 days later contained, in addition to the known antibodies, anti-S plus an unidentified antibody showing characteristics of HTLA. Blood lacking the E, K1, Fy(a), Jk(b) and S antigens was obtained, and 2 least incompatible units were transfused. While administering the second unit, the patient complained of fever and low back pain, and hemoglobinemia was detected. Anti-Do^b was identified in the post-reaction samples by absorption-elution tests, and the patient was confirmed to be Do(a+b–). The first unit transfused during this hemolytic episode tested Do (b+). This case, and a similar case involving anti-Do^a reported in 1986, strengthens the belief that Dombrock antibodies are clinically significant and illustrates the need for their differentiation, prior to transfusion from less clinically significant HTLA antibodies.     

Myofiberbreak-up: a marker of ventricular fibrillation in sudden cardiac death

BACKGROUND: Electrophysiologically, ventricular fibrillation is defined as a "chaotic, random, asynchronous electrical activity of the ventricles due to repetitive re-entrant excitation and/or rapid focal discharge". To this point its morphological equivalent has not been defined. MATERIAL AND METHOD: Several groups of different diseases and types of accidental death in normal subjects were studied. A complete autopsy was performed and the hearts were examined in 432 cases. A total of 16 myocardial samples per heart were processed for histological examination and sections were stained by haematoxylin and eosin or by specific stains. The frequency, location and extent of myocellular segmentation (stretching and/or rupture) of intercalated discs and associated changes of myocardial bundles and single myocells were investigated. A quantitative analysis was performed and the data were processed for statistical evaluation. RESULTS: The frequency of MFB was maximal in coronary (88%) and Chagas (76%) groups followed by the intracranial brain haemorrhage group (52%). The extent of myofiberbreak-up was maximal in coronary/Chagas groups followed by intracranial haemorrhage and transplant groups. CONCLUSIONS: No correlation was seen between gender, age, heart weight, degree of coronary atherosclerosis, myocardial fibrosis, survival and MFB. If our postulate is correct, finding MFB in the myocardium might allow the diagnosis of a malignant arrhythmia followed by cardiac arrest due to ventricular fibrillation even in the absence of clinical information (sudden death out-of-hospital).     

The effect of glucosamine and/or chondroitin sulfate on the progression of knee osteoarthritis: a report from the glucosamine/chondroitin arthritis intervention trial

OBJECTIVE: Osteoarthritis (OA) of the knee causes significant morbidity and current medical treatment is limited to symptom relief, while therapies able to slow structural damage remain elusive. This study was undertaken to evaluate the effect of glucosamine and chondroitin sulfate (CS), alone or in combination, as well as celecoxib and placebo on progressive loss of joint space width (JSW) in patients with knee OA. METHODS: A 24-month, double-blind, placebo-controlled study, conducted at 9 sites in the United States as part of the Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), enrolled 572 patients with knee OA who satisfied radiographic criteria (Kellgren/Lawrence [K/L] grade 2 or grade 3 changes and JSW of at least 2 mm at baseline). Patients with primarily lateral compartment narrowing at any time point were excluded. Patients who had been randomized to 1 of the 5 groups in the GAIT continued to receive glucosamine 500 mg 3 times daily, CS 400 mg 3 times daily, the combination of glucosamine and CS, celecoxib 200 mg daily, or placebo over 24 months. The minimum medial tibiofemoral JSW was measured at baseline, 12 months, and 24 months. The primary outcome measure was the mean change in JSW from baseline. RESULTS: The mean JSW loss at 2 years in knees with OA in the placebo group, adjusted for design and clinical factors, was 0.166 mm. No statistically significant difference in mean JSW loss was observed in any treatment group compared with the placebo group. Treatment effects on K/L grade 2 knees, but not on K/L grade 3 knees, showed a trend toward improvement relative to the placebo group. The power of the study was diminished by the limited sample size, variance of JSW measurement, and a smaller than expected loss in JSW. CONCLUSION: At 2 years, no treatment achieved a predefined threshold of clinically important difference in JSW loss as compared with placebo. However, knees with K/L grade 2 radiographic OA appeared to have the greatest potential for modification by these treatments.     

Lentropin, a protein that controls lens fiber formation, is related functionally and immunologically to the insulin-like growth factors.

Lentropin, a factor present in the vitreous humor of the eye, stimulates lens fiber differentiation from chicken embryo lens epithelial cells in vitro. Lentropin has been partially purified but has not been isolated in sufficient quantity or purity for direct comparison with other growth and differentiation factors. Previous studies have shown that insulin and fetal bovine serum share with lentropin the ability to stimulate lens fiber formation from cultured epithelial cells. In the present study, a number of hormones and growth factors were assayed for lentropin activity. Of those tested, the only substances that had this activity were the insulin-like growth factors (IGFs) somatomedin C (Sm-C/IGF-I) and multiplication-stimulating activity (MSA/IGF-II). Sm-C/IGF-I was approximately 30 times more potent than insulin or MSA/IGF-II in promoting fiber cell formation. A monoclonal antibody to human Sm-C/IGF-I inhibited purified Sm-C/IGF-I, fetal bovine serum, and chicken vitreous humor from stimulating fiber cell differentiation in vitro. This antibody has been shown not to crossreact with insulin and did not block insulin-stimulated lens fiber formation. These findings indicate that lentropin is related to the IGFs and that these factors may play important roles in controlling cell differentiation, in addition to their better-known ability to stimulate cell division.     

Effect of cortisol infusion on the pituitary-adrenal axis of the hypothalamo-pituitary-disconnected fetal sheep.

In order to determine whether cortisol acts directly at the level of the fetal pituitary to promote pars distalis corticotroph maturation, we have infused cortisol into the hypothalamo-pituitary-disconnected (HPD) fetal sheep from 111 to 117 days of gestation. In this study we have measured fetal plasma cortisol and immunoreactive adrenocorticotrophic hormone (ir-ACTH) concentrations between 105 and 116 days of gestation, and we have determined the proportions of adult- and fetal-type corticotrophs in the pars distalis of catheter control fetuses and in HPD fetuses infused with either saline (HPD+SAL) or cortisol (2 mg/day; HPD+F). The fetal plasma cortisol concentrations did not change significantly following HPD. The mean fetal plasma cortisol concentration between 113 and 116 days was threefold higher in the HPD+F fetuses than that measured in HPD fetuses. Following HPD, fetal plasma ir-ACTH concentrations were significantly higher than in catheter control fetuses. Despite the significant elevation in plasma cortisol concentrations in HPD+F fetuses between 113 and 116 days, plasma ir-ACTH concentrations were not different in these fetuses from HPD fetuses infused with saline. At 117 days of gestation in HPD+F fetuses, the proportion of fetal-type corticotrophs in the pars distalis was significantly less than in the HPD+SAL fetuses; however, there was no significant change in the proportion of adult-type corticotrophs in the pars distalis following cortisol infusion. We have shown that cortisol has a direct trophic effect on the maturation of the pars distalis corticotrophs; however, the full maturation of these cells requires an intact hypothalamo-pituitary axis. These findings demonstrate the importance of the fetal hypothalamus in anterior pituitary corticotroph maturation during the last third of gestation.