[Protective function of the skin]. / O zashchitnoi funktsii kozhnogo pokrova.

This paper reviews published data concerning the protective function of skin and discusses factors that may affect its bactericidal capability, including space flight factors that are known to reduce its protective effect. Various concepts of the mechanisms of the bactericidal function are discussed. It is shown that in an enclosed environment the species composition of the resident autoflora and pH value of the skin of an essentially healthy man may change. The qualitative composition of the water-oil film as a source of nutrition and a skin microflora environment is discussed. Its effect on the autoflora composition and localization in various skin areas and, consequently, on the bactericidal capability of different skin areas is described. The skin bactericidal function results from an interaction of various factors that should be taken into consideration when developing flight-oriented hygienic requirements because space flight induces changes in the skin status.

[The electrolyte balance of the blood in dogs exposed to multiple +Gz overloads]. / Elektrolitnyi balans krovi sobak pri mnozhestvennykh peregruzkakh +Gz.

Experiments of the series were carried out using 7 noninbred dogs. In the first series, the animals were exposed to + GZ acceleration of increasing value once or twice a week during 5 months. Each exposure continued until distinct cardiac arrhythmias were seen in ECG. Two weeks after the onset of exposure the dogs displayed hyponatremia and higher K-Na coefficient and two months later they showed hyperkalemia and hypermagnesemia which led to a 1.5 G increase of acceleration tolerance. In the second experimental series, the animals exhibited a beneficial effect of hypermagnesemia on circulation parameters and frequency of cardiac arrhythmias in response to a single + GZ exposure. These observations have demonstrated that electrolyte balance plays an important part in the development of adaptation to sustained acceleration.

[Feeding of the crew of the Saliut-7 orbital station]. / Pitanie ékipazhei orbital'noi stantsii "Saliut-7.

This paper presents physiological and hygienic evaluations of the food supply of Salyut-7 crews in normal conditions, simulation and actual flights of various duration (211, 150, 237, 165 and 126 days). The examinations have shown that the diets used have provided satisfactory health conditions and good nutritional status of the crewmembers.

[Condition of the human skin during a stay in a hermetically closed compartment]. / Sostoianie kozhi cheloveka vo vremia prebyvaniia v germetichno-zamknutom pomeshchenii.

The skin of healthy men kept in an enclosed environment was examined. It was found that exposure resulted in increases of the secretions of the sebaceous glands and sebum cutaneum, number and size of comedones, lipolytic activity of microorganisms, concentration of comedonogenic acids and skin irritating acids. It also caused a greater risk of papular and pustular rashes. Changes in lipid metabolism were consistent with the skin clinical state as well as with the subjective sensations of dirty skin, desquamation and itching. The severity of the above changes was correlated with the pretest physiological and hygienic status of the subjects.

Medical problems of manned space flights onboard orbital stations.

Medical aspects of crew safety and life support as well as biomedical investigations form part and parcel of the preparation and conduct of manned space programs. The list of biomedical problems related to these programs is very long. The present paper concentrates on some of them.

[Reasons for the formation of hydrogen sulfide in regenerated water]. / Issledovanie prichin obrazovaniia serovodoroda v regenerirovannoi vode.

The factors responsible for the formation of hydrogen sulphide in the water reclaimed from the atmospheric condensate were investigated. It was found that hydrogen sulphide developed in reclaimed water due to microorganisms which in the presence of inorganic sulphur (sodium thiosulphate) acquired the capacity to produce hydrogen sulphide, although normally they are not sulphur reducing. Among the microorganisms studied, E. coli showed the highest capacity (100%) and Streptococcus faecalis and Citrobacter freundii showed the lowest capacity (10-20%) to produce hydrogen sulphide.

[Free amino acids in human blood during the initial period of exposure to antiorthostatic hypokinesia]. / Svobodnye aminokisloty krovi cheloveka v nachal'nom periode nakhozhdeniia v usloviiakh antiortostaticheskoi gipokinezii.

The concentration of 17 free amino acids in plasma of 6 test subjects, aged 20, who were for 7 days exposed to head-down tilt and remained on a controlled diet, was measured. The study revealed an increase in the concentration of most amino acids by the end of day 3 and all amino acids by the end of day 7. This indicates that the diet used is a good source of the required amino acids and that there are processes which facilitate an increase of amino acids during the first days of exposure. The concentration of most amino acids returned to the baseline level on the 7th recovery day.

[Hygiene of daily meals of pilots]. / Gigiena povsednevnogo pitaniia letnogo sostava.

The hygienic approaches to daily meals for the flying personnel while on the ground are discussed from the historical point of view. It is indicated that the hygienic requirements for the chemical composition of the daily diet are related to the physiological norms accepted by the nutritional science in the USSR and other countries at various stages of its development. It is shown that the present-day diets for the flying personnel are of high caloric value. The basic physiological and hygienic requirements for the daily diets are given.

[Effect of a space diet on valine concentrations in the blood]. / Vliianie pitaniia ratsionami kosmonautov na soderzhanie valina v krovi.

The content of valine was measured in plasma of 6 healthy male test subjects who were either on a normal or Salyut-5 space diet for 30 days. The measurements were performed with the aid of a Hitachi KLA-3B amino acid analyzer. Unlike other studies, blood samples were withdrawn every 5 days. The results suggest that the postflight decrease of the valine content is associated with the food composition. This makes it necessary to improve the amino acid composition of space diets and the technology of their manufacture. The foodstuffs used in the recovery period should be supplemented with amino acids, particularly valine, to compensate for enhanced anabolic processes.

[Blood amino acids in astronauts before and after a 211-day space flight]. / Aminokisloty krovi u kosmonavtov do i posle 211-sutochnogo kosmicheskogo poleta.

The plasma content of 17 free amino acids of the Commander and Flight-Engineer of Salyut-1-Soyuz-T was examined before flight and on postflight days 1 and 7. The amino acids were measured in an automatic amino acid analyzer Hitachi KLA-3B. Both cosmonauts showed a decrease of most amino acids, particularly essential amino acids. On postflight day 7 the content of most amino acids did not yet return to the preflight level. It can therefore be concluded that the preflight diet should be supplemented with methionine and aspartic acid, and the flight and postflight diets with 7 essential amino acids plus cystine, arginine, proline and aspartic acid.

[Free amino acids in blood plasma during hypokinesia]. / Svobodnye aminokisloty plazmy krovi v usloviiakh gipokinezii.

The study (in a Hitachi KLA-3B analyzer) of 17 free amino acids in plasma of six healthy men under ambulatory and hypokinetic conditions demonstrated the following trend: by day 15 of clinostatic hypokinesia the content of most amino acids increased and by day 30 decreased, reaching the pretest level of falling below it. These variations in the amino acid concentration are viewed as a consequence of the modified relations between anabolic and catabolic processes induced by adaptation to hypokinesia. It is emphasized that the nutrition pattern was different in the hypokinetic study.

[Nutritional status during different regimens of consuming an emergency carbohydrate ration]. / Pishchevoi status pri razlichnykh rezhimakh ispol'zovaniia avariinogo uglevodnogo ratsiona.

Healthy male test subjects were allowed to consume a small-size contingency diet (300 g caramel) during 5 days of survival in a moderate climate in two modes: 1) unifrom intake during 5 days or 2) consumption during the first 3 days and fasting during the remaining 2 days. The first mode proved more advantageous. This conclusion was drawn from evaluations of the general health status, body weight losses, carbohydrate, nitrogen, and mineral metabolism, ECG, and dynamometry.

[Free amino acid content in the blood plasma of cosmonauts before and after a 175-day flight on Saliut-6]. / Soderzhanie svobodnykh aminokislot v plazme krovi u kosmonavtov do i posle 175-sutochnogo poleta na "Saliute-6".

Measurements of 17 free amino acids were performed before and after the Salyut-6 175-day space flight. At R + 1 both crewmembers showed a reduced concentration of most amino acids as compared to the preflight level. By R + 7 the preflight status was not yet reached. It is recommended to enrich the space diet with the following essential amino acids: preflight--methionine, leucine, isoleucine, phenylalanine, lysine, threonine, cystine, and tyrosine; postflight--lysine, threonine, valine, leucine, isoleucine, phenylalanine, methionine, and cystine.

[Metabolism and nutritional status in plane crash situations without food reserves or with low-calorie rations]. / Obmen veshchestv i pishchevoi status pri nakhozhdenii v avariinykh usloviiakh bez zapasov pishchi ili s malokaloriinym ratsionom.

The comparative study of the metabolism and nutritional status of test subjects who 3-5 days were in a contingency situation with no or low-caloric (300 g chocolate) food available demonstrated the advantage of even this inadequate diet as compared to no food.

[Nutrition of aircraft crew members in emergency situations]. / Pitanie ekipazhei samoletov v avariinykh usloviiakh.

An analysis of the arrangement of contingency nutrition of aircrew members, composition and nutrient value of emergency diets used in the USSR and other countries allows the conclusion that low-caloric (subcaloric) diets are replacing isocaloric diets. When developing contingency kits, emphasis is given to portable kits because onboard kits are often inaccessible. This is to be taken into consideration for further improvement of contigency nutrition. Specific attention is to be given to the methods of providing nutrition, maintaining metabolism and work capacity under the conditions of food and water shortage and, consequently, starvation and dehydration of the body.

[Characteristics of the nutritive status of canned meats in emergency "survival" rations]. / Nekotorye osobennosti pishchevogo statusa pri ispol'zovanii miasnykh konservov v avariinykh ratsionakh "vyzhivaniia".

Variations in the nutrient status of test subjects who for 5 days were given a survival diet made of 400 g canned meat were investigated. The energy expenditures of the test subjects were 3000-3200 kcal/day. The study was performed under moderate climate conditions. Anthropometric and biochemical parameters, as well as nitrogen, amino acid, carbohydrate and mineral metabolism were investigated. It has been demonstrated that the survival diet of the above composition can be used by the flight personnel in a contingency situation under moderate climate conditions, provided that water supply is about 1 1/day. The study has shown sporadic hypoglycemia, intensive ketonemia, heavy salt losses, and early protein deficiency. This should be taken into consideration when arranging rescue operations, rehabilitation nutrition and pilot training. It is understood that adequate preflight nutrition may be of great importance.

[Characteristics of the amino acid content in the blood of cosmonauts completing an 185-day flight]. / Nekotorye osobennosti soderzhaniia aminokislot v krovi u kosmonavtov, sovershivskikh 185-sutochnyi polet.

This paper presents data on the content of 17 free amino acids in plasma of the crewmembers before and after the Salyut-6 185-day flight. Measurements were performed by an automatic amino acid analyzer. Postflight the content of most amino acids was lower than preflight. It is concluded that, in order to increase the amino acid supply, preflight diets should be supplemented with all amino acids, particularly, methionine, threonine, isoleucine, cystine, arginine, alanine, histidine, and postflight diets with all amino acids.

[Effect of a 140-day flight on the amino acid content of the blood of cosmonauts]. / Vliainie 140-sutochnogo poleta na soderzhanie aminokislot v krovi kosmonavtov.

The results of studying 17 free amino acids in the plasma of the 140-day Salyut-6 crewmembers are presented. The measurements were carried out by means of a Hitachi KLA-3B amino acid analyzer. The data obtained give evidence that the dietary uptake of amino acids before and during flight should be better controlled, the dietary content of amino acids should be enriched with certain amino acids (primarily methionine and cystine) and more adequately balanced. It is recommended to select space diets on an individual basis, taking into consideration anthropometric and metabolic characteristics of cosmonauts.

[Nutritive value of preserved products in tubes for the feeding of pilots and cosmonauts]. / Pishchevaia tsennost' konservirovannykh produktov v tubakh dlia pitaniia letchikov i kosmonavtov.

The nutritional value of new canned liquid and purée-like foodstuffs in aluminum tubes for aircraft and spacecraft pilots has been determined. The recipes and chemical composition of the food items are described. Particular attention is given to the content of amino acids, fatty acids and minerals. It is shown that canned foodstuffs are inhomogeneous in their chemical composition which is to be taken into consideration when they are used as menu items.