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.     

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.     

Extraction and properties of microcapsulated alpha-chymotrypsin

A method of microencapsulating of the proteolytic enzyme alpha-chymotrypsin into semi-permeable nylon membranes is worked out. The membrane is a polimer of 1,6-hexamethylenediamine and sebacoyl chloride. alpha-Chymotrypsin is enclosed into the capsule together with polyethyleneimine, capable of joining the walls of microcapsules and making the membrane more stable. The optimal concentrations of polyenthyleneimine and alpha-chymotrypsin are 5% and 1% correspondingly. The highest yield of microencapsulated enzyme was obtained for completely acetylated delta-chymotrypsin. The kinetic properties of microencapsulated alpha-chymotrypsin change very slightly as compared to those of the native one.     

Ratio of glycan to teichoic acid in Actinomyces thermovulgaris cell wall

The molar ratio between glycan and teichoic acid was studied in the cell wall of Actinomyces thermovulgaris. A chain of teichoic acid consisting of 13 glycerophosphate units was found to correspond to 6--7 disaccharide units of glycan. The cell wall contains 31% of the glycan of the glycopeptide and 25% of teichoic acid. The content of glycan was calculated using the concentration of muramic acid in the wall. The cell wall was found to contain 1.02% of O-acetyl groups.     

Hypoxia impairs vasodilation in the lung

Alveolar hypoxia causes pulmonary vasoconstriction; we investigated whether hypoxia could also impair pulmonary vasodilation. We found in the isolated perfused rat lung a delay in vasodilation following agonist-induced vasoconstriction. The delay was not due to erythrocyte or plasma factors, or to alterations in base-line lung perfusion pressure. Pretreating lungs with arachidonic acid abolished hypoxic vasoconstriction, but did not influence the hypoxia-induced impairment of vasodilation after angiotensin II, bradykinin, or serotonin pressor responses. Progressive slowing of vasodilation followed angiotensin II-induced constriction as the lung oxygen tension fell progressively below 60 Torr. KCl, which is not metabolized by the lung, caused vasoconstriction; the subsequent vasodilation time was delayed during hypoxia. However, catecholamine depletion in the lungs abolished this hypoxic vasodilation delay after KCl-induced vasoconstriction. In lungs from high altitude rats, the hypoxia-induced vasodilation impairment after an angiotensin II pressor response was markedly less than it was in lungs from low altitude rats. We conclude from these studies that (a) hypoxia impairs vasodilation of rat lung vessels following constriction induced by angiotensin II, serotonin, bradykinin, or KCl, (b) hypoxia slows vasodilation following KCl-induced vasoconstriction probably by altering lung handling of norepinephrine, (c) the effect of hypoxia on vasodilation is not dependent on its constricting effect on lung vessels, (d) high altitude acclimation moderates the effect of acute hypoxia on vasodilation, and (e) the hypoxic impairment of vasodilation is possibly the result of an altered rate of dissociation of agonists from their membrane receptors on the vascular smooth muscle.