Changes in the absorptive capacity of the reticuloendothelial system during combined radiation-thermal injury

From experiments in rats it is shown that the aggravating effect of heat on the outcome of radiation sickness may be attributed to the enhancement of impairment of the resistance of the body to autoinfection and endotoxaemia due to early post-burn depression of the absorptive function of the reticulo-endothelial system.     

Activity of the enzymatic drug-metabolizing system of the liver in combined radiation-thermal injury

The functional status of the enzyme monooxygenase system of rat liver was assessed by the hexenal test at different time intervals following irradiation (6 Gy), thermal affection, and the combined effect of the two factors. The data obtained were indicative of the potentiation of the inhibiting action of the two factors on the detoxicating function of liver.     

Activation of arachidonic acid metabolism--a protective reaction of the body during irradiation and combined radiation-thermal damage

Metabolic activity of arachidonic acid cascade enzymes in rabbit polymorphonuclear leucocytes sharply rises during the first day of irradiation, decreases at the highest mortality period, and is restored at later times. The inhibitors of the activity of lipoxygenase and cyclooxygenase and the release of arachidonic acid have been shown to increase the mortality rate and to decrease the average lifetime of rats exposed to ionizing radiation and a mixture of radiation and heat.     

Thyroid gland activity and motor activity during dog ontogenesis]

The locomotor activity (LA) and the level of the protein-bound iodine (PBI) in the blood serum were investigated in 62 puppies at the age of 1--12 months. A parallel elevation of PBI and the LA was observed the first 4 months after birth. The second peak of the LA at the age of 7--9 months was not accompanied by any PBI rise. Inhibition of the thyroid function with mercasolyl increased the LA at the age of 1--3 months and decreased it at the age of 7 months. An increase of the LA one month after thyroidectomy was found at the age of 1 and 3.5 months. The activity of puppies operated on at the age of one month showed a sharp fall after 2--4 months. The data on various effect of thyroid hormones on puppies of different age pointed to the complex relation between the LA and the thyroid gland function.     

Interphase death of thymus cells in combined radiation-thermal injury against a background of prophylactic administration of alpha-tocopherol and indomethacin

The administration of alpha-tocopherol prior to radiation and thermal affection enhances chromatin degradation in thymocytes, increases the number of pyknomorphic cells in the critical zone of thymus, and enhances injury to erythrocyte membranes. The preventive administration of indomethacin does not influence the interphase cell death.     

Thyroid gland function during cross adaptation to heat and cold in man

Plasma thyroxine (T₄), triiodothyronine (T₃) and thyrotropin (TSH) levels were monitored in 10 healthy euthyroid male subjects of the age group 20 to 30 years before and during heat and cold acclimatisation schedule in a sequential manner. The subjects were exposed to 45C DB and 30% relative humidity in a hot chamber for 2 hours daily for 8 consecutive days. Subsequently they were exposed to cold for 4 hours daily at 10C for 21 days. The mean plasma T₄ and T₃ concentration before exposure to heat were 7.87±0.82 ug/dl and 159.8±9.1 ng/dl respectively. A significant decrease in both T₄ (p<0.05) and T₃ (p<0.01) levels to mean values of 6.4±0.76g/dl and 129±7.9 ng/dl was recorded on day 4 of exposure to heat. Further significant decrease (p<0.05) over the preceding T₃ levels was observed on day 8 of heat exposure. Plasma T₄ and T₃ on day 21 of cold exposure was not significantly different from the levels reckoned after last day of heat exposure but was significantly lower than the pre-exposure values. Throughout the thermal stress schedule there was no change in the TSH levels. These observations suggest that a decrease in thyroid hormone levels during exposure to heat might be an adaptive process which continues even during cold acclimatisation.     

Salivary gland hypofunction in elderly patients attending a xerostomia clinic

Objectives: To investigate the aetiological factors and the prevalence of salivary gland hypofunction (SGH) in patients complaining of xerostomia. Design Prospective, clinical study. Setting Xerostomia clinic in the Department of Oral Medicine at Liverpool University Dental Hospital. Subjects 100 consecutive patients, aged 60 years or older, referred for investigation of xerostomia. Interventions Patients were asked specific questions concerning their complaint of oral dryness and associated orofacial symptoms. A detailed medical history was recorded and patients underwent a systematic examination of the head, neck and oral structures. All patients underwent haematological, biochemical, immunological investigations, urinalysis and sialometry. Further investigations and referrals to other specialists were undertaken when appropriate. Main outcome measures The causes of xerostomia were established on the basis of clinical and laboratory findings and SGH was defined as an unstimulated whole salivary flow rate of <0.2ml/min, Results: The causes of xerostomia were identified as: Sjögren's Syndrome (40), iatrogenic (22), psychogenic (14), idiopathic (19), diabetes (1), candidosis (3) and alcohol (1). Sixty five percent of the patients studied had SGH. Conclusions This study has shown that 65% of patients whose presenting complaint was xerostomia had objective evidence of SGH. Several aetiological factors were identified, the most common of which was Sjögren's Syndrome. The possibility of associated systemic diseases should be considered when establishing the aetiology of SGH.     

Thyroid gland in dwarf mice

Stereological methods were used to compare thyroids of dwarf mice and of their heterozygote littermates. In the thyroid of dwarf mice unorganized cellular masses, adipous tissue and ultimobranchial cysts are abundant. Follicles are small and their distribution function is unimodal. The number of cells per follicle is considerably lowered if compared with the normal. In control mice the distribution function of thyroid follicles is bimodal. These data show that the origin of the thyroid anomaly in dwarf mice is due to a drastic diminution of cell divisions, probably resulting from the lack of growth hormone.     

The peculiarities of separate and combined exposure to low dose-rate gamma-radiation and 232Th nitrate on thyroid gland

We studied the effects of both: of the separate and of the combined exposure to gamma-radiation (absorbed doses for 30 days were 1.4-1.8 cGy, for 90 days were 4.3-5.4 cGy) and 232Th nitrate (in concentrations 6.0; 20.0 and 60.0 mg/l) on the CBA line mice thyroid gland. Hat is shown the thyroid gland response to the combined exposure is significant in an appearance of non-linear effects of interaction. The intensiveness of the radiation influence (time and doses) is revealed to affect on the biological response direction in thyroid gland. The intensity of this effect was depended on the correlation between the radiation activity and the chemical components concentration. The dispersive analyses showed that all the studied factors caused structural changes in thyroid gland in this experiment, but the gamma-radiation influence causes the primary contribution.     

The therapeutic properties of an alcohol extract of plasma in a combined radiation-thermal lesion

The intravenous injection of an alcoholic plasma extract to mice after the combined exposure to radiation and heat decreases lethality, restores the investigation-and-orientation activities and oxygen consumption, favors the growth of body mass and healing of burns. The antioxidant effect of the extract manifests itself by the decreased rate of formation of lipid peroxidation products in the liver and the suppressed spontaneous and latex-induced chemiluminescence of neutrophils.     

Thyroid gland function in heatstroke]

Development of thermal stroke in rats with the action of high external temperature (45 degrees C) was accompanied by a reduction of accumulation of I131 in the thyroid gland, a fall in the protein-bound-iodine--I131 and in the amount of thyroxin in the peripheral blood plasma, and also by a fall in the rate of disappearance from the blood of Nal131 injected intravenously. A relative decrease of the content of mono- and particularly of diiodthyrosines, and also, slightly, of iodthyronines occurred in the trypsine hydrolyzates of the thyroid gland at the moment of the thermal stroke development.     

The effect of cystamine on the survival of mice and endogenous colony-formation in combined radiation-thermal injuries

In experiments on mice it was shown that cystamine exerts its protective action not only against the concurrent effect of ionizing radiation and weak thermal injury but also against the effect of heat (burn) 48 h after irradiation with a midlethal dose (30-day-death decreased from 95 to 20%).     

The estimation of the nitric oxide role in the aggravation of combined radiation-thermal injuries

The influence of specific inhibitor of inducible NO synthase S-ethil-isothiourea (as "Difetur" preparation) on liver NO production level, and 30-days survival, mean survival time and probability of mortality within animals under combined radiation/thermal injury (CRTI) were evaluated. Experiments were carrying out on mice (whole body gamma-irradiation at the dose of 7 Gy + 10% body surface full-thickness thermal burn). It was shown, that CRTI induce 2-fold statistical significant increase of NO production in liver of experimental animals. Mice pretreatment with Difetur preparation lead to practically full inhibition of NO production. In the group of animals, with Difetur administration during first two days after CRTI 60% mice survived as compared 15% survive in control group. In pair with data on probability of mortality it was suggested that growth of NO production in the early period of CRTI increase sensitivity of animals to pathological processes leading to death on 10-12 days.     

Two separate receptors for prolactin in the rabbit mammary gland

Rabbit mammary gland PRL receptors in the microsome fraction were solubilized with the zwitterionic detergent Chaps, and were separated into two fractions (Fr. A and B) by ion-exchange chromatography. The number of receptors in Fr. B was about 2.2 times greater than in Fr. A. In sucrose gradient centrifugation analysis, PRL receptors in Fr. A and Fr. B sedimented at different positions. After binding 125I-PRL, the apparent molecular weight (mol wt) of the PRL receptor in Fr. A changed from 42,400 to 65,500 and that in Fr. B changed from 89,400 to 108,000, suggesting that each binding subunit interacts with one PRL molecule. Cross-linking 125I-PRL to receptors revealed little change following SDS-PAGE, in the autoradiogram patterns of the microsome PRL receptors, either in the presence or absence of dithiothreitol. Both the microsome and the Chaps extract contained two major binding subunits (mol wt, 83,200 and 36,800) and one minor subunit (mol wt, 20,800). The mol wt of the dominant PRL receptors in Fr. A and Fr. B were 36,800 and 83,200, respectively. The latter form did not dissociate into a 36,800 mol wt form, suggesting that the rabbit mammary gland contains two independent binding subunits with mol wt of 36,800 and 83,200. Data showed that PRL receptors in the rabbit mammary gland are mostly the high Kd type receptor with a mol wt of 83,200.