Extravasation injuries on regional neonatal units.

This survey of regional neonatal intensive care units determined a prevalence of 38 per 1000 neonates who sustained an extravasation injury that caused skin necrosis. Most injuries occurred in infants of 26 weeks gestation or less, with parenteral nutrition infused through intravenous cannulae. Common treatments were exposing wounds to the air, infiltration with hyaluronidase and saline, and occlusive dressings.

HIV-associated myocarditis treated with zidovudine (AZT).

Congestive cardiomyopathy has been reported in patients infected with human immunodeficiency virus (HIV). In this report of diffuse lymphocytic myocarditis in a patient who tested positive for HIV antibody after receiving blood from an HIV-positive donor, the patient failed to respond to conventional medical therapy. Although no opportunistic infection or malignancy was observed by electron-and light-microscopic examination of the endomyocardial tissue sample at biopsy, it was decided to give the patient zidovudine (AZT) at a dosage of 200 mg every 4 hours. Definite clinical improvement was noted on repeat right heart catheterization and endomyocardial biopsy 3 months after the initiation of AZT therapy. This case supports the theory that myocarditis can be caused by HIV and suggests that AZT may be useful in the treatment of patients with HIV-associated cardiomyopathy.

Coronary artery anomalies: a review of more than 10,000 patients from the Clayton Cardiovascular Laboratories.

We reviewed the records of 10,661 patients who had undergone coronary angiography at the Clayton Foundation Cardiovascular Laboratories between 1 June 1974 and 15 March 1986, and identified major coronary artery anomalies in 83 adults. In addition, we included in our review 9 adults and 2 adolescents who had been referred for evaluation of anomalies documented elsewhere. Here we present the clinical and angiographic data for all 94 patients (76 men and 18 women). Most patients were men who presented with chest pain. The most common anomaly, found in 38 patients, was origin of left circumflex coronary artery from right coronary artery or right aortic sinus. In contrast to other studies, which have not shown increased incidence of coronary atherosclerosis in the anomalous circumflex artery, 71% of our patients with this anomaly had significant coronary atherosclerosis in the proximal portion of the anomalous vessel. The posterior course of the anomalous circumflex coronary artery may predispose this vessel to atherosclerosis in patients with coronary disease. The overall incidence of atherosclerotic disease in coronary arteries was 68% (64 of 94 patients) in the present study.

Digitalis withdrawal in elderly nursing home patients.

Nursing home patients were studied to determine the usefulness of a maintenance dose of digoxin in elderly patients with normal sinus rhythm. Of 64 patients, 26 were identified to be on digoxin. Thorough history and physical examination were done on all the patients. Baseline electrocardiogram showed normal sinus rhythm in 19 patients, who were observed very closely for the period of four months after withdrawal of digoxin. Eighteen of 19 patients did well without digoxin, which suggests that most of the elderly nursing home patients with normal sinus rhythm do not need a maintenance dose of digoxin.

Cardiac sarcoidosis: two cases with ventricular tachycardia and review of cardiac involvement in sarcoid.

Patients with significant cardiac sarcoidosis are at increased risk of sudden death from ventricular dysrhythmias or conduction disturbances. We report two patients whose initial manifestation of cardiac sarcoidosis was nonsustained ventricular tachycardia unresponsive to standard antiarrhythmic measures. Endomyocardial biopsy aided the diagnosis in each patient. This technique is helpful in establishing the diagnosis of cardiac sarcoidosis, which causes life-threatening ventricular dysrhythmias.

Myocardial infarction associated with cocaine abuse.

We report a patient who sustained a myocardial infarction after inhaling cocaine. He developed a persistent wall motion defect that was present 18 months after the acute event despite resolution of electrocardiographic evidence of infarction.

A characterization of mitochondrial and mycoplasmal DNAs associated with cloned HeLa thymidine kinase minus cells.

HeLa S3 cells were cloned, recloned, and then selected for growth in the presence of increasing concentrations of bromodeoxyuridine. Cultures of these cloned thymidine kinase minus (TK-) cells were found to harbor mycoplasma which sedimented with mitochondria in sucrose density step gradients. Examination of mitochondrial DNA (mitDNA) components by restriction enzyme analysis and electron microscopy revealed no gross alterations in size, sequence arrangements, or replicative forms compared with mitDNA of HeLa S3 cells. Restriction enzyme cleavage sites for BamHI (one site), PstI (two sites) and HpaI (three sites) were mapped on this genome relative to the three cleavage sites for each of EcoRI and HindIII, respectively. Analysis of topological complexity revealed similar frequencies of catenated mitDNA molecules in both cloned TK- (22.5 +/- 1.5% of mass) and HeLa S3 cells )25.6 +/- 1.5% of mass). Unicircular dimers comprise 6.7 +/- 0.9% of the mitDNA mass in cloned TK- cells but were not detected in HeLa S3 mitDNA. Examination of the mycoplasmal contaminant of mitochondrial DNA after digestion with various restriction enzymes and agarose gel electrophoresis revealed that most of the DNA was distributed in discretely sized fragments in patterns that can probably be used to unambiguously identify and classify the organism.

Microheterogeneity detected in circular dimer mitochondrial DNA.

Exhaustive EcoRI digests of circular dimer mitochondrial DNA (mtDNA) from mouse cell lines LD and LDTK- yield two major fragments whose average lengths are slightly smaller than the corresponding fragments of circular monomer mtDNA from mouse LA9 and LMTK- cells. A third fragment approximately 400 nucleotide pairs in length is frequently produced in less than molar yield. Exhaustive EcoRI digests of circular dimer mtDNA from human acute myelogenous leukemic leucocytes yield three major fragments. The presence of mtDNA resistant to cleavage as well as fragments of intermediate sizes indicatesmicroheterogeneity in the genomic positions of EcoRI recognition sequences in both mouse and human circular dimer mtDNA. Analysis of the distribution averages of circular contour lengths indicates microheterogeneity in the sizes of mouse LD and human mtDNAs. The denatured-renatured EcoRI fragments frequently contain a small loop(s) of single-strand DNA as would occur for deletion(s) or addition(s) of single-strand DNA as would occur for deletion(s) or addition(s) of nucleotide sequences in some of the circular dimer molecules.