Blood metal concentrations of manganese, lead, and cadmium in relation to serum ferritin levels in Ohio residents.

The objectives of this study were to assess ferritin-specific profiles of blood metal concentrations such as manganese, lead, and cadmium and to evaluate whether ferritin may affect the behavior of the blood metals in relation to menstruation, menopause, or sex in Ohio residents. Recruited participants included residents from Marietta, East Liverpool, and Mt. Vernon, OH, USA, who were aged 30-75 years and lived at least 10 years in their respective town. The levels of the neurotoxic metals such as manganese, cadmium, and lead were assayed in whole blood. Serum was analyzed for ferritin level [as a biomarker of iron (Fe) status]. An association between blood metal concentrations and independent variables (age, serum ferritin, manganese exposure status, and sex) by multiple regression analysis was assessed, controlling for various covariates such as BMI, educational level, smoking, and alcohol drinking status. Overall, the geometric means of blood manganese, cadmium, and lead levels of all participants (n = 276) were 9.307 µg/L, 0.393 µg/L, and 1.276 µg/dL, respectively. Log serum ferritin concentrations were inversely associated with log blood manganese concentration (ß = -0.061 log ferritin and ß = 0.146 categorical ferritin) and log blood cadmium concentrations (ß = -0.090 log ferritin and ß = 0.256 categorical ferritin). Log serum ferritin concentrations were not associated with log blood lead concentrations. Variables of age, sex, and exposure status were not associated with log manganese concentrations; however, log blood cadmium concentrations were higher in older population, women, and smokers. Log blood lead concentrations were higher in older population, men, and postmenopausal women. Our study showed that iron deficiency is associated with increased levels of blood manganese and cadmium, but not blood lead, in Ohio residents. These metals showed different toxicokinetics in relation to age, sex, and menopausal status despite similar relationships between ferritin and metal concentrations.

Muscle calcium metabolic effects of hypokinesia in physically healthy subjects.

The incompleteness of electrolyte deposition during hypokinesia (HK; diminished movement) is the defining factor of electrolyte metabolic changes, yet the effect of prolonged HK upon electrolyte deposition is poorly understood. The objective of this investigation was to determine the effect of muscle calcium (Ca(++)) changes upon Ca(++) losses during prolonged HK. Studies were conducted on 20 physically healthy male volunteers during a pre-experimental period of 30 days and an experimental period of 364 days. Subjects were equally divided in two groups: control subjects (CS) and experimental subjects (ES). The CS group ran average distances of 9.2 ± 1.2 km day(-l), and the ES group walked average distances of 2.3 ± 0.2 km day(-l). Muscle Ca(++) contents, plasma Ca(++) concentrations, and Ca(++) losses in urine and feces were measured in the experimental and control groups of subjects. The muscle Ca(++) contents decreased (p < 0.05), and plasma Ca(++) levels and Ca(++) losses in the urine and feces increased (p < 0.05) in the ES group compared with their pre-experimental levels and the values in their respective CS group. Muscle Ca(++) contents and plasma Ca(++) levels and urinary and fecal Ca(++) losses did not change in the CS group compared to their pre-experimental levels. It is concluded that prolonged HK increase plasma Ca(++) concentrations and Ca(++) losses in Ca(++) deficient muscle indicating decreased Ca(++) deposition.

[Biochemical diagnosis of immobilization osteoporosis].

The authors have ascertained informative laboratory tests for diagnosis of immobilization osteoporosis and prognostic tests of reparative osteogenesis in its presence. A study was conducted in 97 patients (mean age 39.8 +/- 9.5 years) with bone nonunion and immobilization osteoporosis diagnosed densitometrically (DPXA, Lunar, USA). The proposed procedures are topical if no densitometric study is available and the prediction of osteogenesis on the basis of the phosphatase index is of informative value at the X-ray negative stage (1 month after surgery). The procedures are available and cost-effective; their sensitivity is 75-77%.

[Effects of antiorthostatic hypokinesia on blood levels of interleukine-1beta and interleukine-6 in primates].

Investigations with Macaca mulatta of 4-5 yrs. of age with the body mass of 4.5-6.5 kg showed that 10 days of tilting with the head end at .5 degrees reduced body temperature but not levels of interleukine-1beta and interleukine-6 in blood plasma. On the next days after return of animals to cages IL-6 was found to increase sharply in more than 10 times. On subsequent 4 days both IL -1beta and IL-6 were within the normal range.

Effect of age-related chronic immobility on markers of bone turnover.

UNLABELLED: The effects of acute immobilization on bone turnover are well known, but the effects of chronic hypomobility with aging have not been studied. In a cohort of 1064 frail elderly subjects, immobility was significantly associated with serum PINP but not serum CTx after adjusting for confounders. The effect of immobility may be more marked on bone formation than on bone resorption. INTRODUCTION: Accelerated bone turnover and rapid bone loss caused by acute immobilization is well recognized, but the effects of age-related chronic reduction in mobility on bone turnover have been less well studied. We assessed the associations between bone turnover and measures of mobility in a cohort of elderly subjects. MATERIALS AND METHODS: We measured serum levels of the aminoterminal propeptide of type I collagen (PINP), a marker of bone formation, and serum concentrations of the carboxyterminal telopeptide of type I collagen (CTx), a marker of bone resorption, as well as serum intact PTH, serum 25 hydroxyvitamin D (25OHD), mobility, and static balance in a well-characterized sample of 1064 elderly men and women living in residential aged care facilities. Serum creatinine, phosphate, albumin, and calcium were measured in a randomly selected subgroup of 447 subjects. RESULTS: The subjects were elderly and frail; their mean age was 86.0 years (range, 65-101 years); 69% used a walking aid; and 77% were vitamin D deficient (serum 25OHD level < 39 nM). Both serum PINP and CTx increased with age in both sexes. Elevated PINP or CTx was significantly correlated with high PTH, creatinine, and albumin in both genders, except for albumin in women. Age- and gender-adjusted serum CTx and PINP were significantly higher in those with poorer mobility and those with worse static balance. In multivariate analyses, higher serum PINP but not CTx was associated with poorer mobility and worse static balance. CONCLUSIONS: Our findings suggest that poor mobility contributes to the state of accelerated bone turnover usually seen in the elderly. The effect of chronic relative immobility may be more marked on bone formation than bone resorption.

[Using electromagnetic irradiation of extra high frequency for the correction of desynchronisation]. / Vykorystannia elektromahnitnoho vyprominiuvannia nadvysokoï chastoty dlia korektsiï desynkhronoziv.

The infradian rhythmicity of the open-field behavior of rats under the influence of EHF-waves was investigated. It was shown the development of desynchronosis under the influence of EHF-waves on intact rats. Under the influence of EHF-waves the development of desynchronosis on hypokinesic rats was remarkable decreased. It was found that EHF-waves are able to modify the temporary organization of physiological systems, however, the magnitude and the character of these changes depend on functional state of the organism. It has been suggested that the ability of EHF-waves to modify temporary organization of physiological systems plays an important role in mechanisms of their biological action.

Changes in bone turnover markers during 14-day 6 degrees head-down bed rest.

Osteoporosis caused by exposure to microgravity represents a serious clinical concern, but the mechanisms have yet to be fully elucidated. The present research aimed to elucidate the effects of microgravity environments on bone turnover, with a specific focus on changes in bone resorption markers such as type I collagen cross-linked N-telopeptides (NTx) and deoxypyridinoline (Dpyr), for which scant data are available regarding detailed time course. Methods using 6 degrees head-down bed rest were utilized to simulate a microgravity environment. Eleven adult male volunteers underwent 6 degrees head-down bed rest for 14 days; measurements were made of serum and urine Ca concentrations, in addition to osteocalcin (OC), bone alkaline phosphatase (ALP), NTx, and Dpyr as bone turnover markers. By the end of bed rest, concentrations of bone ALP had significantly increased, but OC displayed a tendency toward decrease. Concentrations of Dpyr significantly increased from day 6, remaining elevated until the end of bed rest. Concentrations of NTx significantly increased on day 13 and at the end of bed rest. Serum and urinary concentrations of Ca increased significantly at the end of bed rest. Bone ALP represents a relatively early marker of osteoblast differentiation at the matrix maturation phase and OC is a late marker in osteoblast differentiation at the calcification phase. The present results therefore suggest an absolute increase in bone resorption and normal or reduced bone formation, together causing prominent uncoupling and rapid bone loss after simulated microgravity. Moreover, the present results suggest that bone resorption is enhanced at an early stage of exposure to microgravity environments.

Fluid electrolyte changes during prolonged restriction of motor activity in rat.

Water and electrolyte changes in urine and plasma of rats during prolonged restriction of motor activity (hypokinesia), have been studied, on 90 male Wistar rats (375 to 396 g) during a 15 day period of prehypokinesia and during a 90 day period of hypokinesia (HK). All rats were divided equally into two groups: rats placed under ordinary vivarium conditions served as vivarium control rats (VCR) and rats subjected to HK served as hypokinetic rats (HKR). The hypokinetic effect was carried out by keeping the HKR group in small individual cages that restricted all their movements in all directions without hindering food and water intake. During the 15 days of the prehypokinetic period and during the 90 days of the hypokinetic period, fluid consumed and eliminated in urine, food intake, body weight, plasma sodium and potassium concentration and excretion thereof in urine, plasma osmolality, total protein plasma concentration, whole blood haemoglobin and haematocrit concentration were measured. In the HKR group water and food intakes decreased significantly (p < 0.05) when compared with the VCR group, whilst diuresis, excretion of sodium and potassium in urine, plasma sodium and potassium concentration, plasma osmolality, plasma protein concentration, whole blood haemoglobin and haematocrit increased significantly (p < or = 0.05) when compared with the VCR group. It was concluded that prolonged exposure to HK induces significant changes in water balance and in both urinary and plasma sodium and potassium in rat.

Daily zinc supplementation effect on zinc deficiency in rats during prolonged restriction of motor activity.

The objective of this investigation was to evaluate the effect of 47 mg zinc supplementation on deficiency of zinc in rats during 98 d of restriction of motor activity (hypokinesia), which appeared by higher plasma zinc concentration. One Hundred 13-week-old Sprague-Dawley male rats weighing 360-390 g were used to perform the studies: They were equally divided into four groups: 1. Unsupplemented control animals (UCA); 2. Unsupplemented hypokinetic animals (UHA); 3. Supplemented control animals (SCA); and 4. Supplemented hypokinetic animals (SHA). For the simulation of the effect of hypokinesia (HK), the UHA and SHA were kept in small individual cages made of wood, which restricted their movements in all directions without hindering food and water intake. The SCA and SHA received daily with their food an additional amount of zinc. Before and during the experimental period of 98 d, plasma, urinary and fecal zinc, balance of zinc, food intake, and body weight were determined at different intervals. In the SHA and UHA, the concentration of zinc in plasma, and the elimination of zinc in urine and feces increased significantly when compared with the SCA and UCA, whereas the balance of zinc was negative. The body weight and food intake decreased significantly in the SHA and UHA when compared with the SCA and UCA. The increased plasma concentration of zinc in both the SHA and UHA groups was in contrast to the observed hypozincnemia during prolonged immobilization as during prolonged hospitalization. This reaction suggests that there may be some other mechanisms that are affecting the process of control and regulation of zinc metabolism during prolonged HK. It was concluded that exposure to prolonged restriction of motor activity of rats induces significant increases in plasma concentration, fecal and urinary elimination of zinc in the presence of negative zinc balance and regardless the daily intake of large amounts of zinc with their food, leading to zinc deficiency.

Daily magnesium supplementation on serum and urinary magnesium changes in rats during prolonged restriction of motor activity.

The objective of this investigation was to determine whether a plentiful magnesium (Mg2+) supplementation might be used to normalize or prevent Mg deficiency. This is manifested by increased rather than decreased serum Mg2+ concentration as is observed during prolonged hospitalization, which is developed during prolonged hypokinesia (HK) (decreased motor activity). Eighty male Wistar rats with an initial body weight of 370-390 g were used to perform the studies: They were equally divided into four groups: 1. Unsupplemented control animals (UCA); 2. Supplemented control animals (SCA); 3. Unsupplemented hypokinetic animals (UHA); and 4. Supplemented hypokinetic animals (SHA). For the simulation of the hypokinetic effect, the hypokinetic animals were kept in small individual cages made of wood which restricted their movements in all directions without hindering food and water intake. The control and hypokinetic supplemental animals receive 0.9 mg/mL Mg sulfate daily with their drinking water. Prior to and during the experimental period, urinary excretions of Mg, calcium, and phosphate along with their concentrations in serum, water intake, and urine excretion, and body weight were determined in the control and hypokinetic animals. In the supplemental and unsupplemental hypokinetic rats, urinary excretions and serum concentrations of electrolytes increased significantly, whereas serum concentration and urinary excretion thereof remained unchanged in the supplemented and unsupplemented control animals. It was concluded that a daily intake of large amounts of Mg supplementation cannot be used to prevent or normalize Mg deficiency in rats during prolonged exposure to HK.

Water metabolic parameter changes in rhesus monkeys during exposure to prolonged restriction of motor activity.

The objective of this investigation was to determine the effect of prolonged restriction of motor activity (hypokinesia [HK]) on several parameters of water metabolism in primates. The studies were performed on 12 rhesus monkeys aged 4-5 yr (5.10-6.85 kg) during the hypokinetic period of 90 d and during the prehypokinetic period of 30 d. They were divided into two equal groups: the first group was placed under ordinary vivarium conditions (vivarium control animals) and the second group was subjected to 90 d of HK (hypokinetic animals). For the simulation of the hypokinetic effect, the primates were immobilized on their abdomens in special tables. The legs of the monkeys were immobilized with hip and knee joints extended. The primates retained freedom of movement at elbow, wrist, and ankle. During the pre-experimental period of 30 d and during the experimental period of 90 d, the following variables were determined: body weight, total body fluid content, specific total body fluid, mean fluid consumed and eliminated in urine, specific plasma resistance, hematocrit level, and plasma concentrations of sodium (Na) and potassium (K). In the hypokinetic primates, body weight decreased significantly when compared to the controls. Mean fluid intake, total body fluid, and specific total body fluid decreased, whereas mean daily fluid loss and specific mean daily fluid elimination increased significantly. Specific plasma resistance, hematocrit level, and plasma electrolyte concentrations increased significantly when compared to the control primates. It was concluded that prolonged restriction of motor activity induces significant changes in water metabolic parameters of primates leading in decreased total water content of the body.

[The effect of the 120-day antiorthostatic hypokinesia on the functional state of female thyroid]. / Vliianie 120-sutochnoi antiortostaticheskoi gipokinezii na funktsional'noe sostoianie shchitovidnoi zhelezy u zhenshchin.

Investigations of eight healthy female volunteers aged 26-37 in 120-days antiorthostatic hypokinesia (AOH, -5 degrees) gave original data about peculiarities of adaptation and functional state of female thyroid and the thyreotrophic activity of adenohypophysis. The test-subjects were divided into two equal groups. Group 1 administered a set of countermeasures including exercise and pharmacy. In the other group, no health control was used. By days 90-100 in AOH thyroid glands of the females were slightly more compact but remained diffuse. Thyroid sizes were not altered. Chemical/biochemical examination did not elicit any noteworthy shifts in the thyreotrophic activity of hypophysis or thyroid function in the bedrested females. The countermeasures did not enhance the thyroid function. Results of the investigation point to the completion of thyroid adaptation of females by days 90-100 in AOH.

[Proteolytic processes in the rat brain and serum in hypokinesia and the adaptive effect of delta-sleep inducing peptide]. / Proteoliticheskie protsessy v mozge i syvorotke krovi krys pri gipokinezii i adaptivnom vliianii del'ta-son indutsiruiushchego peptida.

It has been demonstrated for the first time that a single injection of the delta-sleep inducing peptide (DSIP) results in long-term alteration of proteolytic enzyme activity within a broad range of pH. Using Ca(2+)-independent neutral endopeptidases from the synaptosomal fraction of rat brain and blood serum kallikrein as an example, it has been shown that DSIP activates limited proteolysis. This effect may contribute to the alteration of the set and "active" concentration of regulatory peptides and peptide hormones to the induction of the preadaptive state. DSIP also causes the redistribution of activity between Ca(2+)-dependent and Ca(2+)-independent neutral endopeptidases associated with synaptosomal membranes, particularly under hypokinetic conditions. The significant decrease of the Ca(2+)-activated neutral proteinase I activity may be one of the mechanisms whereby the modulating effect of DSIP manifested as regulation of the number of glutamate receptors and limitation of effect of this excitatory neuromediator is realized under stress. Preliminary injection of DSIP prevents disturbances in the permeability of lysosomal membranes under long-term (24 hours) hypokinesia.

[Characteristics of the pool of blood free amino acids of rats during extended hypokinesis]. / Kharakteristika pula svobodnykh aminokislot plazmy krovi krys pri dlitel'noi gipokinezii.

23 free amino acids (AA) were analyzed in blood plasma of rats during 70- and 140-day hypokinesia (HK). The total content of free AA after 70-day HK was found to level down by one third as a result of reduction of the majority of AA excluding glutamate, glutamine, and cystine, the concentrations of which exceeded controls by 21.8%, 4.6%, and 6.3%, respectively. The period of HK extended up to 140 days, the sum of free AA remained lowered; however, glutamate and cystine levels were higher than in control by 10.3% and 183.2%, respectively. The causes for changes of absolute (mM/l) and relative (% in the pool) concentrations of individual AA and their metabolic groups with account for specificity of neuroendocrine regulation and energy metabolism in the skeletal muscles, myocardium, liver, kidneys in dehydrated organism are discussed.