Search

All 1 H and 13 C NMR signals of the four poly(phenylenephthalides): polydiphenylenephthalide (P(DPh)-1), polyterphenylenephthalide (P(TPh)-2) and two sequentially ordered polymers with different ratios of alternating diphenylenephthalide and terphenylenephthalide units (P(DTPh)-3, P(DDTPh)-4) were assigned unequivocally with two-dimensional NMR techniques ( 1 H- 1 H COSY and NOESY; 1 H- 13 C HSQC and HMBC). There are four types of polyphenylene fragments: not symmetrical end, symmetrical inner, symmetrical pre-end and formally symmetric pre-end. The equivalent carbon atoms in these fragments have different chemical shifts. A full additivity of the chemical shifts for the side phthalide and polyphenylene carbon atoms was revealed. A new structure of diads with a mirror symmetry plane, passing through the middle of aromatic moieties, is proposed. Copyright © 2017 John Wiley & Sons, Ltd., (Copyright © 2017 John Wiley & Sons, Ltd.)

In a 105-day experiment simulating crew life in a space exploration vehicle, shifts in the nutritional status were assessed in 6 test subjects differing in the body mass index, basal metabolism, attitude to the diet, physical exercise and workload. Results of the investigation showed that because of the hard physical work the nutritional status of test subjects was described by more intensive basal metabolism, elevated metabolism of carbohydrates and lipids, and their increased mobilization from depots. Food ration, though it was sufficient to sustain health and fairly high performance, failed to meet fully individual taste preferences and energy needs for physical activities. The heavy workloads required mobilization of lipids from adipose depots, and a decrease of the hepatic detoxification and metabolic capacities. Self-limitation of eating protein-rich desserts led to a relative deficiency of protein intake. These faults of the diet were the reason why 4 out of 6 test subjects reduced their basal metabolism and lost body mass. Recovery of metabolism and slowdown of the body mass loss were achieved by supplementing meals with available protein-containing products.

Two groups of male volunteers for 4-day dry immersion with and w/o countermeasures (support load imitator (SLI) or high-frequency electrostimulator) underwent ultrasonic investigation (USI) of the liver, gastroduodenal organs and vessels, and blood biochemical analysis. Two other groups of volunteers performed the 13C-methacetin breath test (13C-MBT) to study the effects of immersion and SLI on the liver detox activity and metabolic capacity. In immersion, USI diagnosed slowdown of blood flow along the hepatic vein and signs of plethora in the abdominal venous system. In addition, immersion was accompanied by increases in blood pepsinogen, pancreatic amylase, total bilirubin, the "indirect" fraction specifically, insulin and C-peptide. 13C-MBT detected deceleration of 13C-methacetin inactivation and diminution of the liver metabolic capacity. Administration of the countermeasures did not improve the ultrasonic image of hemodynamic alterations in the liver and abdomen significantly. High-frequency electrostimulation cancelled out changes in all biochemical parameters except C-peptide; SLI was favorable to recovery of pepsinogen and amylase baseline values only. Besides, the SLI wearing prevented loss of the 13C-methacetin inactivation rate but was not effective enough against diminution of the hepatic metabolic capacity.

Ultrasonic investigations of 8 male volunteers for bed rest at -15 degrees showed plethora in peritoneal veins and slow blood flow through the liver with no effect on biochemical parameters. Breath test with 100 mg of 13C-methacetine (MBT) pointed to diminution of the metabolic capacity and decline of the hepatic detoxification activity due to the hemodynamic effects. MBT can be used as a nonintrusive method for diagnosing functional changes in the liver induced by hemodynamic developments in microgravity and other situations triggering similar hemodynamic mechanisms.

(1) H and (13) С NMR spectral assignments have been provided for low-molecular reference monomers, poly(diphenyleneoxidephthalide) and periodic copoly(arylenephthalide) derivatives such as AB, ABB, and ABBB (where A = terphenylenephthalide and B = diphenyleneoxidephthalide) using (1) H-(1) H COSY, (1) H-(13) C HSQC and HMBC NMR techniques. Distinctive (13) C NMR chemical shifts of a main chain have been observed containing fragments of similar structures and lateral phthalate groups being part of various diads., (Copyright © 2013 John Wiley & Sons, Ltd.)

Six male volunteers for dry immersion (DI) modeling the microgravity effects on human organism were subjects in the GI evacuatory function investigation. The investigation was aimed to evaluate liquid food evacuation from the stomach (13C-acetate test) and time of chymus orocecal transit (H2-inulin test). The 13C-acetate test did not reveal changes in stomach evacuatory activity after 4 days in DI. The H2-inulin test demonstrated shortening of chymus transit along the small intestine and extension of chymus passage from the ileum to cecum. Subsequent reduction of inulin metabolism in the large intestine suggested inhibited passage of these GI segments. The results showed that stability of liquid evacuation from the stomach and acceleration of chymus transit along the small intestine hinder evacuation of the large intestine content which is the primary cause for inhibition of GI evacuatory activity in DI.

Functioning of the digestive system was investigated in 10 volunteers for 7-day dry immersion. The experimental conditions were found to raise secretory activities of the stomach, pancreas and liver, and to increase spectral indices of the GI electrical activity on the background of a higher than usual insular secretion and lowered gastrin secretion. The elevated GI electrical activities and changes in their ratios were a fallout of the increased gastric secretion and elevated intestines tone in fasting test-subjects and displayed a close similarity to the changes induced by caffeine stimulation, long-term bed rest or space flight.

Ultrasonic investigations of the abdominal organs and splanchnic veins were performed in essentially healthy subjects tilted at 12 degrees and 15 degrees for the period of 12 hrs. and 24 hrs. Tilting produced typical redistribution of venous blood and body liquids toward the cranial end. In its turn, blood redistribution caused excessive venous plethora and abdominal stasis. These were succeeded by expansion of large veins in the abdomen, enlargement of parenchymal organs and contraction of their echogenicity, and thickening of the hollow organs walls. Changes in the gastrointestinal functions before meal included elevated gastric, hepatic and pancreatic secretion, and an increased amount of intestinal content. The investigations demonstrated that stasis of the splanchnic veins altered functioning of the digestive organs in tilted human subjects.

Experimental results were compared with data of cutaneous electro-gastroenterography and USI of the gastrointestinal tract in human subjects at different tilt angles and after different periods of tilting. It was shown that increased GIT electrical activity in tilted subjects before meal is representative of increasing intracavetary contents of the stomach and small intestine. More intensive electrical activity results from elevation of the GIT tone and peristalsis. Extension of tilt duration raises GIT tone and peristalsis and, consequently, stimulates the GIT electrical activity. Further increase of the tilt angle suppresses evacuation and, therefore, the electrical activity Analysis of the results allows conclusion that increased parameters of the total energy of GIT electrical potentials are reflective of elevated tone of GIT walls, whereas elongation of the potential peaks envelope implies activation of peristalsis.

In 62 normal males and females gastrointestinal (GI) electrical activity was evaluated before and after standard breakfast with the method of epicutaneous electrogastroenterography (EGEG) with the use of AgCl electrodes and original hard- and software "Gastroenterograph" developed by the authors. Spectral analysis (SA) of GI electrical potentials enabled quantification of the electrical activity of the stomach, duodenum, jejunum, ileum and the whole of the small intestine. The stomach and the small intestine were main contributors to the total GI electrical activity during fasting. Changes in the functional activity of the digestive system after the meal were characterized by increases in selected SA parameters (length of the spectral curve and area underneath), dissociation between their values and redistribution of ratios in different GI segments.

Modern wool textile factories are characterized by hygienically inadequate labour conditions which include exceeding dust and microbe contamination of the air in the working zone and poor microclimate conditions in some shops. Basing on the studies of the air contamination sources, the contributors propose recommendations for health-related improvement of the air conditions.

The biological value of the protein component of three modifications of the Salyut space diet was measured in laboratory studies and in simulated space flights. Three experimental runs of up to 68 days in duration were carried out on 20 volunteers. During the study the following parameters of protein metabolism were measured: total protein and protein fractions in serum; urea, uric acid and creatinine in blood; total nitrogen, urea, ammonia, uric acid and creatinine in urine. The results obtained showed that the diet modifications provided an adequate nutritional status and a normal level of the above parameters of protein metabolism.

The space diets used in flight of five permanent Salyut-6 crews were instrumental in assuring their adequate nutritional status and work capacity required to fulfill flight programs. Some of them complained that sterile canned foods became distasteful; due to this, a space diet consisting of 65% freeze-dried foodstuffs was developed and tested.