Particle deposition onto a human head: influence of electrostatic and wind fields

Steatosis--accumulation of triacylglycerol in hepatocytes--is a common finding in liver biopsy specimens. The commonest form is macrovesicular change, which occurs in response to a wide range of insults. In the absence of other features, the pathologist cannot ascertain the likely cause on morphological features alone but can give an indication of the severity of steatosis. Close clinicopathological correlation is required to establish the cause. In most instances, macrovesicular steatosis is at least potentially reversible. Although it may be thought of as a benign condition, it may be associated with the development of necroinflammation and fibrosis--so-called steatohepatitis. The classic example of this is alcoholic hepatitis, but there is increasing awareness of steatohepatitis occurring in nonalcoholics: NASH. Distinction between alcoholic hepatitis and NASH on purely histological grounds may be impossible; careful clinicopathological discussion is mandatory. Microvesicular steatosis is generally a more severe disease than the macrovesicular form and is seen in a variety of conditions in which there is either an inherited or an acquired defect in beta-oxidation of fatty acids; the former includes mitochondrial cytopathies and disorders of ureagenesis, and the latter includes acute fatty liver of pregnancy and Reye's syndrome. This review describes the morphological features of steatosis and steatohepatitis, considers their pathogenesis, and outlines the clinical significance of the different patterns of injury.     

Feasibility study of CPR in the water

More than 8000 drownings occur each year in the United States alone. With the increased popularity of scuba diving for commercial and sport purposes, one would predict an increase in related deaths or accidents. Yet procedures to administer first aid are limited to mouth-to-mouth, and external cardiac compressions must await moving the victim to a firm surface. This study discusses the technique of placing a victim upon the rescuer's chest and initiating full cardiopulmonary resuscitation (CPR) immediately on the site. During emergency regulator resuscitation (E.R.R.), ventilations are administered by use of a slightly modified, factory-calibrated scuba regulator. The techniques were tested on an instrumented aquatic CPR mannequin and found to meet the published criteria for successful CPR.     

Dental and gingival pain as side effects of niacin therapy

Two 65-year-old white men with coronary heart disease, given niacin therapy for dyslipidemia for 5 months, developed intense dental and gingival pain that was associated with increases in dose and that was relieved with discontinuance of niacin treatment. One individual who took crystalline niacin had beneficial effects on lipid levels, while the other person who took a delayed release preparation had little lipid effect. The cause of these previously unreported side effects of niacin therapy is uncertain but may be related to prostaglandin-mediated vasodilatation, hyperalgesia of sensory nerve receptors, and potentiation of inflammation in the gingiva with referral of pain to the teeth.     

Exclusive radical radiotherapy of laryngeal tumors: 10-year experience

Exclusive irradiation is used to treat primary neoplasms localized to the larynx because it is known to be able to cure, or at least control, the disease in a high percentage of cases without affecting speech. We report our ten-year experience in the Radiotherapy Department of Chieti Hospital. From 1985 to 1994, exclusive radiotherapy was used to treat 87 patients bearing histologically proved epidermoid carcinomas of the larynx. The patients average age was 67 years. The primary site was the glottis in 64 cases and the supraglottic and subglottic areas in 21 and 2 cases, respectively. The lymph nodes were clinically positive in 8 patients (9%) and negative in 79 (91%). The minimum follow-up was 20 months. All the patients were treated with cobalt 60 beams; the daily dose was 2 Gy, fractionation was 5 days a week. Average tumor dose was 64 Gy (range: 55-70 Gy). Disease-free survival actuarial curves show 72% five-year survival for glottic cancer (75% for N0, 80% for T1 and 61% for T2-T3-T4 cases) and 21% for supraglottic cancer (25% for N0 cases). To conclude, irradiation is confirmed to be a useful tool to treat early laryngeal cancer, while new combinations of surgery, chemotherapy and irradiation are needed to treat locally advanced cancer.     

Phosphorylation of DNA polymerase alpha-primase by cyclin A-dependent kinases regulates initiation of DNA replication in vitro

DNA polymerase alpha-primase is the only known eukaryotic enzyme that can start DNA replication de novo. In this study, we investigated the regulation of DNA replication by phosphorylation of DNA polymerase alpha-primase. The p180 and the p68 subunits of DNA polymerase alpha-primase were phosphorylated using Cyclin A-, B- and E- dependent kinases. This phosphorylation did not influence its DNA polymerase activity on activated DNA, but slightly stimulated primase activity using poly(dT) single-stranded DNA (ssDNA) without changing the product length of primers. In contrast, site-specific initiation of replication on plasmid DNA containing the SV40 origin is affected: Cyclin A-Cdk2 and Cyclin A-Cdc2 inhibited initiation of SV40 DNA replication in vitro, Cyclin B-Cdc2 had no effect and Cyclin E-Cdk2 stimulated the initiation reaction. DNA polymerase alpha-primase that was pre-phosphorylated by Cyclin A-Cdk2 was completely unable to initiate the SV40 DNA replication in vitro; Cyclin B-Cdc2-phosphorylated enzyme was moderately inhibited, while Cyclin E-Cdk2-treated DNA polymerase alpha-primase remained fully active in the initiation reaction.     

Computer-based smoking cessation interventions in adolescents: description, feasibility, and six-month follow-up findings

The impact of adolescent smoking cessation clinics has been disappointing due to low participation rates, high attrition, and low quit rates. This paper describes two computerized self-help adolescent smoking cessation intervention programs: 1) a program utilizing the expert system which is based on the transtheoretical model of change and 2) a popular action-oriented smoking cessation clinic program for teens which was modified for computer presentation. High participation rates in the program among 132 smokers demonstrate the high feasibility and acceptability of the programs. Quit rates of up to 20% were observed during the intervention, and an additional 30% made unsuccessful quit attempt(s). The 6-month follow-up findings indicated that adolescents were poorly prepared to maintain abstinence.