The role of non-clostridial anaerobic infections in the etiology, pathogenesis, clinical aspects and treatment of inflammatory diseases of the paranasal sinuses

This paper presents the results of clinical and bacteriological examinations of 116 patients with suppurative rhinosinusitis. Bacteriological tests under anaerobic conditions revealed in 53% of the patients nonclostridium anaerobic bacteria that were highly resistant to most antibiotics and sensitive to metronidazole and its derivatives. A protocol of conservative therapy of suppurative rhinosinusitis was developed. The protocol included etiotrophic antianaerobic drugs (metronidazole and its derivatives) and oxygenation of paranasal sinuses. This therapeutic approach yielded positive effects in 92% of the patients.     

Effect of adaptation to hypoxia on the working properties of muscles and energetics of muscular work

The working properties and heat formation of skeletal muscles were investigated during contraction in laboratory rats adapted to hypoxia and corresponding controls. During indirect electrical stimulation of the muscle the strength of contraction, work, and fatigue ability of the muscle were determined and the increase in temperature of the muscle as a result of the contraction was measured. Adaptation to hypoxia was shown not to affect the strength of contraction of the muscle or the quantity of work done. However, hypoxia leads to a reduction in the temperature effect of muscular contraction, expressed per unit work done. This indicates an increase in the efficiency of muscular work during adaptation to hypoxia. The fatiguability of muscles is increased in hypoxic rats. The changes in the energetics of muscular contraction during adaptation to hypoxia and to cold are different in direction.Laboratory of Thermoregulation, Institute of Clinical and Experimental Medicine, Siberian Branch. Academy of Medical Sciences of the USSR, Novosibirsk. Laboratory of Thermoregulation, Institute of Physiology and Experimental Pathology of Highland Areas, Academy of Sciences of the Kirghiz SSR, Frunze. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 3, pp. 259–260, March, 1978.     

Role of modern methods of morphological research in the exact definition of the biological characteristics and morphogenesis of human breast cancer

Combined use of modern methods of morphologic investigation will allow one in every diagnosed case of breast carcinoma to determine its histogenesis, make a differential diagnosis. Knowledge of biological features of malignant cells will allow one to apply an individual approach to treatment and prognosis. To clarify the morphogenesis of breast carcinoma, it is important to study the stromal component, as parenchymal-stromal relationship is a fundamental link in structural homeostasis.     

Chronic mercury exposure at different concentrations produces opposed vascular responses in rat aorta

Mercury chloride exposure for 30 days decreases NO bioavailability and increases oxidative stress. However, the mechanisms underlying the effects of mercury on the cardiovascular system are not completely understood, and it is not known if they are dose‐dependent or if some concentrations have no harmful effects. Thus, we investigated the effects of chronic exposure to doses low (half) and high (2.5‐fold higher) than that needed to obtain 29 nmol/L of HgCl₂ on the vascular function. Three‐month‐old male Wistar rats received intramuscular (i.m.) HgCl₂ for 30 days and were divided in three groups: lower (Low Hg); higher (High Hg); and saline was used as the control. High Hg exposure increased the contractile response to phenylephrine (PHE) in aortic rings, but Low Hg reduced it. The hyporesponsiveness in the Low Hg rats was blunted by endothelial denudation and NOS inhibition with l ‐NAME (100 μmol/L). The phosphorylated‐eNOS/eNOS protein ratio increased in the aortas of Low Hg rats. In the High Hg group, endothelial denudation increased the PHE‐induced contractions, while l ‐NAME had no effects and indomethacin (10 μmol/L), losartan (10 μmol/L) and apocynin (30 μmol/L) reduced this response. In the High Hg group, protein levels of the NADPH oxidase subunit gp91phox and cyclooxygenase‐2 increased. Our results support previous suggestions that High Hg increases oxidative stress that might activate an inflammatory cascade and the renin‐angiotensin system. However, very low Hg concentrations below the level considered safe still reduced vascular reactivity, suggesting the need for special attention to continuous exposure as a putative cause of increased cardiovascular risk.     

Sensitivity and specificity of first screen mammography in the Canadian National Breast Screening Study: a preliminary report from five centers

Sensitivity and specificity of first screen mammography in a randomized screening trial at five centers are reported. A total of 23,101 women underwent mammography; in 139, breast cancer was detected at first screening; in 20, less than 12 months after first screening; and in 47, at second screening. All 206 cancer cases were histologically confirmed, and 174 were defined as being detectable at first screening. Average length of follow-up for all women was 3.2 years. Interpretations of first screen mammograms by the center radiologists were matched to known outcomes. Simultaneous blind review was performed by a single reference radiologist with mammograms from all 206 cancer cases and those of a random sample of 739 women not known to have breast cancer at 15 months or more after initial screening. Overall, the five screening centers achieved a sensitivity of 69% (range, 60%-78%), a specificity of 94% (range, 93%-96%), a positive predictive value of 8.6% (range, 3%-16%), and a negative predictive value of 99.7% (range, 99.6%-99.9%).     

Compensatory and repair processes in the thyroid gland of month-old desympathized rats

Department of Pathological Anatomy, Department of Biology, and No. 1 Department of Internal Medicine, Izhevsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 4, pp. 507–509, April, 1988.