Role of calcium in secretion of chorionic gonadotropin by first trimester human placenta.

The role of calcium in regulation of secretion of human chorionic gonadotropin (hCG) by first trimester human placental minces in vitro has been investigated. Depletion of calcium in the medium by addition of EGTA resulted in a drastic decrease in the levels of immunoreactive hCG in the medium with consequent of accumulation of hCG in the tissue. Addition of A 23187 which is a calcium ionophore resulted in a dose dose dependent increase in the hCG in the medium and this stimulatory response could not be observed in the absence of calcium. Use of lanthanum (a calcium antagonist) in place of calcium in the medium used resulted in a significant decrease in the levels of hCG in the medium. Addition of veratridine (a sodium channel activator) stimulated hCG secretion in a dose dependent manner. These results suggest that calcium is essential for normal secretion of hCG by human placenta.     

Neuroactive steroids in the brain and age and sex specificity of behavior and anxiety: An experimental study

Changes in the brain’s neuroactive steroid levels, behavior in the open field, and the anxious-phobic status of male and female rats in the course of development have been studied. An increase in the motor and exploratory activity and emotionality in rats of both sexes in the pubertal period and a decrease in their values in mature and old animals have been detected. Anxiety has no sexual dimorphism in adult animals; it is significantly higher in males than in females in the prepubertal and pubertal periods of development and is higher in old females than in males of the same age. An increase in the level of corticosterone in some brain structures in maturing and old rats has been found; the testosterone concentration increases in one-month-old and adult animals but decreases in old individuals, while the estradiol concentration in all studied brain structures of male and female rats was low in all periods of postnatal life. Correlation analysis has shown modulation by steroid hormones of the changes in behavioral responses during development.     

Apoptosis and related proteins in placenta of intrauterine fetal death in prostaglandin f receptor-deficient mice

The present study investigated whether the increase of apoptosis in the placenta is associated with intrauterine fetal death in prostaglandin F receptor-deficient mice. Apoptosis was demonstrated within placental and decidual tissue by the TUNEL method. The majority of apoptosis was found in syncytiotrophoblast tissues. Enhanced TUNEL-positive staining in the syncytiotrophoblast layer was scattered in the placental tissues in clusters of apoptotic cells in the death group. Marked TUNEL-positive cells were identified in decidua of both groups. The rate of apoptosis in the placenta and decidua in the death group was higher than that in the survival group (P < 0.05). Immunohistochemical analysis showed that the level of active caspase-3 protein expression in the placenta in the death group was much higher than that in the survival group. The level of Bcl-2 protein expression in the placenta in the death group was much lower than that in the survival group. Western blot analysis demonstrated that increased expression of the active form of caspase-3 was detected in the placenta and decidua in the death group compared with that in the survival group. In contrast, a decrease in the expression of Bcl-2 was detected in the placenta and decidua in the death group compared with that in the survival group. Enhanced expression of Bax:Bcl-2 ratio was detected in placenta and decidua in the death group compared with that in the survival group. Thus, significantly increased apoptosis in the mouse placenta and decidua might be involved in the pathophysiologic mechanism of intrauterine fetal death.     

Density-dependent variation in lifetime breeding success and natural and sexual selection in Soay rams

Variation in male lifetime breeding success (LBS) is central to understanding selection, yet it has rarely been measured in natural populations of large mammals. Here, we first describe variation in the opportunity for selection in cohorts of Soay rams (Ovis aries) on the archipelago of St. Kilda, Scotland, that were born during years of varying population density. Variation in LBS is closely coupled with demography, as rams born in years of low density following population crashes enjoy greater LBS than do those born in high-density years. Paradoxically, the opportunity for selection was greatest in the largest cohorts, those born in years of high population density, owing to low juvenile breeding success and overwinter survival. Variation in longevity and the contribution of nonbreeders were the most important components of the total variance in LBS in cohorts born in years of high density, while variation in fecundity was more important in cohorts born in low-density years. The opportunity for sexual selection is thus stronger in cohorts born in low-density years, as many rams in these cohorts survive to compete for mates as adults in subsequent ruts. Variation in population density in the year of birth also influenced the intensity of selection. Individuals born in years of high population density underwent strong natural selection in favor of longer hindlimbs over their first winter. In contrast, in cohorts born in low-density years, there was no natural selection on hindlimb in the first year of life. Longer hindlimbs were associated with increased fecundity over the entire lifetime of individuals born in low-density years. Natural and sexual selection thus act on the same trait in the same direction at different life-history stages in Soay rams, depending on the population density experienced in the year of birth.     

Levels of linoleic acid and saturated and monounsaturated fatty acids in selected lipid fractions of the serum and platelets in patients with coronary arterial disease

The levels of serum fatty acids in the serum and in the serum fractions of cholesterol esters (ECH) and triglycerides (TG) and the levels of these acids in these fractions of platelets were compared in healthy controls and in patients with clinically manifested coronary arterial disease. Decreased level of linoleic acid was found in the serum and in the ECH fraction of the serum in the patients, with a rise in the level of palmitic acid in the ECH fraction of the serum of these patients. The level of linoleic acid in the ECH and TG platelet fractions in these patients was not different from that in the healthy controls, while in the platelet TG fraction of the patients the level of palmitoleic acid was raised, and the level of oleic acid was increased in the platelet ECH fraction.     

Control of hydatid disease in Wales.

OBJECTIVES--To evaluate the success of the south Powys hydatid control programme by analysis of trends in cystic disease in humans and sheep and dog infestation. DESIGN--A review of hospital admissions for human hydatid disease in 1984-90, abattoir prevalence surveys of hydatid cysts in adult sheep, arecoline acetarsol and coproantigen surveys of prevalence of Echinococcus infestation in dogs. SETTING--All hospitals in England and Wales, three abattoirs, and dog populations in mid ands south east Wales. SUBJECTS--Residents of England and Wales admitted to hospital between 1984 and 1990 with a new diagnosis of human hydatid disease (International Classification of Diseases (ICD), ninth revision, code 122) acquired in the United Kingdom. RESULTS--The average annual incidence of human hydatid disease in Powys, mid-Wales, fell from 3.9x10(-5) in 1974-83 to 2.3x10(-5) in 1984-90. Age specific incidence rates in Wales declined over this period only in children, and no cases occurred in children (<15 years) in Powys. Two Welsh children who lived in Gwent and mid-Glamorgan were infected. Prevalence of hydatid cysts in old sheep from south Wales declined during the control period, but in 1993 prevalence of cysts was 13%. Prevalence of E granulosus infestation was zero in the control area in 1993, but it was 2.4% in Powys dogs outside the control area in 1989 and 9.2% in dogs in Gwent in 1991. CONCLUSIONS--Human hydatid disease has been successfully controlled in south Powys but cystic echinococcosis is still endemic in sheep in mid-Wales, and there is a focus of infection in humans, sheep, and dogs in the bordering areas of Gwent and mid-Glamorgan. There is considerable potential for an upsurge in human cases if control measures are relaxed.     

Protein synthesis in skeletal muscle of the perfused rat hemicorpus compared with rates in the intact animal.

The rate of protein synthesis was measured in muscles of the perfused rat hemicorpus, and values were compared with rates obtained in whole animals. In gastrocnemius muscle of fed rats the rate of synthesis measured in the hemicorpus was the same as that in the whole animal. However, in plantaris, quadriceps and soleus muscles rates were higher in the hemicorpus than those in vivo. In the hemicorpus, starvation for 1 day decreased the rate of protein synthesis in gastrocnemius and plantaris muscles, in parallel with decreases in the RNA content, but the soleus remained unaffected. Similar effects of starvation were observed in vivo, so that the relationships between rates in vivo and in the hemicorpus were the same as those in fed rats. Proteins of quadriceps and plantaris muscles were separated into sarcoplasmic and myofibrillar fractions. The rate of synthesis in the sarcoplasmic fraction of the hemicorpus from fed rats was similar to that in vivo, but synthesis in the myofibrillar fraction was greater. In the plantaris of starved rats the rates of synthesis in both fractions were lower, but the relationships between rates measured in vivo and in the perfused hemicorpus were similar to those seen in fed rats. The addition of insulin to the perfusate of the hemicorpus prepared from 1-day-starved animals increased the rates of protein synthesis per unit of RNA in gastrocnemius and plantaris muscles to values above those seen in fed animals when measured in vivo or in the hemicorpus. Insulin had no effect on the soleus. Overall, the rates of protein synthesis in the hemicorpus differed from those in vivo. However, the effect of starvation when measured in the whole animal was very similar to that measured in the isolated rat hemicorpus when insulin was omitted from the perfusate.     

Protein phosphorylation in Bradyrhizobium japonicum bacteroids and cultures.

Protein phosphorylation was demonstrated in Bradyrhizobium japonicum bacteroids in vivo and in cultures in vivo and in vitro. Comparison of in vivo-labeled phosphoproteins of bacteroids and of cultured cells showed differences in both the pattern and intensity of labeling. In cultured cells, comparison of the labeling patterns and intensities of in vivo- and in vitro-labeled phosphoproteins showed a number of similarities; however, several phosphoproteins were found only after one of the two labeling conditions. The labeling intensity was time dependent in both in vivo and in vitro assays and was dependent on the presence of magnesium in in vitro assays. Differences in the rates of phosphorylation and dephosphorylation were noted for a number of proteins. The level of incorporation of 32P into protein was only 2% or less of the total phosphate accumulated during the in vivo labeling period. Several isolation and sample preparation procedures resulted in differences in labeling patterns. Phosphatase inhibitors and several potential metabolic effectors had negligible effects on the phosphorylation pattern. There were no significant changes in the phosphorylation patterns of cells cultured on mannitol, acetate, and succinate, although the intensity of the labeling did vary with the carbon source.     

Experimental and epidemiological estimation of seasonal and climato-geographical features of non-specific resistance of the organism to influenza

One and the same series of live influenza vaccine from the strains B/Dushanbe/66 and B/Leningrad/67 or A2/Moscow/21/65 administered intranasally to non-immune persons in Leningrad and 'krasnodar in winter caused an increase in body temperature in 6.7-8% of vaccinated subjects, but in summer in 0.8%. In the transitional seasons of the year (in May and in October), 6.3-16.8% of reactions were observed in Murmansk and 0.1% in Krasnodar. An increase in antibodies in the vaccinated in Leningrad and Arkhangelsk in winter was observed 1.5 times more frequently than in summer. In Krasnodar, seroconversion occurred in only 5.7% in May and october, but in 31.3% in January; in Murmansk in 41.2-48% in May and in 75.6-78.8% in October. The seasonal as well as latitudinal and climatic differences in reactogenicity and antigenic activity of the vaccine can be explained by seasonal oscillations in non-specific resistance of people of influenza viruses. The importance of this factor in the mechanism of seasonal occurrence of influenza is discussed.     

Comparison of glucose-6-phosphate dehydrogenase activity in healthy and atretic follicles in rat ovary

Changes in the glucose-6-phosphate dehydrogenase activity have been determined in relation to atresia of Graafian follicles in the rat ovary. Induction of atresia in follicles either due to absence of hCG in the hormonally stimulated immature ovaries or by repeated injections of pentobarbitone sodium to proestrous rats caused significant rise in the enzyme activity. Measurement of enzyme activity in isolated follicular compartments of healthy and atretic follicles revealed that it is significantly higher in the thecal tissue than the granulosa. Increase in enzyme activity in the atretic follicles than the healthy ones occurs due to its rise both in theca and granulosa cells. The significance of these changes in the enzyme activity in healthy and atretic follicles are discussed in relation to the precocious luteinization of cells in the follicular envelope with the onset of atresia.     

辣椒雄性不育系与保持系花药POD、SOD和EST同工酶表达差异研究

利用辣椒质核互作雄性不育材料,采用聚丙酰胺凝胶垂直板电泳技术,研究了在花药发育不同时期,甜椒和辣椒核质互作雄性不育系及其保持系POD、SOD和EST同工酶的差异.结果表明:不育系与保持系,在花药发育的不同时期POD同工酶表达种类及表达活性之间存在差异,其中甜椒不育系在减数分裂期POD同工酶的活性非常低,辣椒雄性不育系在减数分裂期及花粉成熟期分别多一条POD特征带.不育系与保持系之间SOD同工酶的表达活性及其表达种类无明显差异.在减数分裂期和花粉成熟期,甜椒和辣椒不育系与保持系花药EST同工酶酶带均存在明显的差异.     

Natural incidence of interruptions in the internal elastic lamina of caudal and renal arteries of the rat

Interruptions in the internal elastic lamina (IEL) have been quantified by light microscopy in the caudal arteries of different strains of rats and in caudal and renal arteries of (i) male and female virgin rats up until 2 years of age, (ii) repeatedly bred rats and (ii) hypertensive rats. Results showed that gaps in the IEL exist in caudal arteries of adult males in all strains studied, but to a lesser extent in the hairless mutant. In the virgin Wistar rat these interruptions in the IEL form with age in both caudal and renal arteries, and are more numerous (i) in the male than in the female in both arteries, and (ii) in the caudal than in the renal artery in both sexes. Repeated breeding in the Wistar rat abolishes the sex difference in incidence of IEL gaps in both renal and caudal arteries. The Sprague-Dawley breeder rat is more susceptible than the Wistar breeder to their formation in the renal artery. Hypertension in the male consistently increases the formation of IEL gaps in the renal but not in the caudal artery. The importance of local factors, e.g. hemodynamics, in the formation of these defects in the IEL, and their possible relationship with the development of arteriosclerosis is discussed.     

Agonistic behaviour in domestic hens: the influence of housing method and group size

The incidence of agonistic behaviour was recorded over 1 year in laying hens of two strains, housed either in battery cages or in deep-litter pens in groups of either three or six birds. Aggressive head-pecking was more frequent in pens than in cages and in groups of six than in groups of three. Threats were more frequent in pens and in groups of six light-hybrids. Other pecking at the plumage was more common in cages in groups of six and in the light-hybrid than in the medium-hybrid strain. Observations showed that hens occupy a considerable area when engaging in threat displays: this suggests that the physical restraint of crowding may play an important part in limiting this behaviour. Two reasons for the reduction of aggressive head pecking in caged birds were suggested: firstly, inhibition of the subordinate hens' behaviour because they were constantly in the sphere of influence of the dominant bird and secondly, because agonistic encounters may be triggered only by the entry of other birds into an individual's 'personal space' and not by continuous proximity.     

The Retention of Cadmium and Selenium Influence in Fowl and Chickens of F1 Generation

The retention of cadmium and selenium influence on Cd retention in the muscle, liver and kidneys of hens, chickens and in eggs was studied. Cadmium (Cd) as cadmium chloride (CdCl(2)) and selenium (Se) as sodium selenite (Na(2)SeO(3)) were added to feed at dosages: group 0-control, group 1-20 mg/kg Cd, group 2-30 mg/kg Cd + 4 mg/kg Se. The birds were exposed to Cd for 8 weeks. Cadmium level in hens and cocks was found highest in the kidneys, followed by the liver and muscle. Se supplementation resulted in Cd increase in the muscle tissue and in the reduction of Cd content in the liver and in significant decrease in the kidneys (p < 0.05). A higher Cd level in the yolk and lower in the white was noted in both experimental groups. Nonsignificant increase of Cd in eggs was noted in experimental groups with Se supplementation. Level of cadmium in organs of 7-day-old chicks hatched from Cd-treated hens in both experimental groups was low but the tendency to accumulate preferentially the Cd in the liver and kidneys was recorded. Supplementation of selenium in hens and cocks was not reflected in the decrease of Cd in these two organs of F(1) chickens but was reflected in increase in the muscle. In spite of relatively high Cd levels in the organs of layers no layer-egg-chickens transfer was observed. It was confirm that kidneys and liver are organs more attacked by dietary cadmium than muscle. Supplementation of low dose of Se resulted in decrease of cadmium deposition in analyzed organs.     

Colony-forming units of the bone marrow and spleen of immunodeficient mice after stimulation of the cells with thymalin

It has been previously demonstrated by the authors that histological characteristics of colony-forming units (CFUs) in normal mice prove a certain shift in their differentiation in erythroid direction comparing to the bone marrow CFUs. Thymectomy of mature animals is accompanied with weakening growth of granular colonies at cloning of the bone marrow CFUs and with loss of stability in direction of splenic CFUs differentiation. Polypeptide preparation of the thymus--thymalin stimulates growth of the granulocytic colonies from the splenic CFUs in thymectomized mice both in in vivo and in vitro experiments. Differentiation of the bone marrow CFUs is normalized under the effect of thymalin in in vivo experiment only. The data obtained confirm the suggestion made by R. V. Petrov on existence of T-cell clone, enhancing CFUs differentiation in granulocytic direction. Activation of this clone in the spleen is revealed at thymectomy and stimulation of the cells with thymalin both in in vivo and in vitro experiments. Thus, affirmations are obtained on differences of clonic T-cell regulation of the CFUs differentiation in the bone marrow and in the spleen.     

Effect of ionizing radiation on the synthetic activity of blood system cells in ground squirrels in different physiological states of animals

The functional (synthetic) activity of blood lymphocytes and bone marrow haemopoietic cells in ground squirrels during the annual cycle as well as in hibernating and awaken animals in winter have been studied by fluorescent microspectrometry. The effect of ionizing radiation on animals in different functional states of the hibernation-arousal bout was investigated too. It was shown that the synthetic activity (parameter alpha) in blood lymphocytes was minimal in hibernating state in winter and maximal in active euthermic spring animals, then slightly decreased in June and more considerably decreased in the prehibernating autumn period. In awake animals in winter, the values of parameter alpha reached the same values as in summer. The changes of parameter alpha in bone marrow haemopoietic cells were essentially the same: the minimal values were observed in the prehibernation autumn period and in awake animals in winter the alpha values were slightly higher than in active euthermic animals in summer. The maximal synthetic activity in bone marrow haemopoietic cells in active euthermic spring animals is due mainly to cells in G1-G2 phases of the cell cycle. The decrease of the synthetic activity in summer is a result of the cell transition from G2 to mitosis and transition of a part of cells to G0 When investigating the hibernation-arousal bout in ground squirrels in winter, during arousal, we found two stages considerably differing in both the values of parameter alpha in bone marrow haemopoietic cells and the number of blood cells. The synthetic activity and the total number of blood and bone marrow cells in ground squirrels irradiated in the state of deep hibernation did not differ significantly from the state of non-irradiated hibernating animals. The negative effect of radiation appeared upon the arousal of these animals but it was expressed to a lesser degree in comparison with the animals irradiated in the active state. It was found that the acute irradiation of animals during arousal from hibernation in the second stage caused the most pronounced functional inactivation and cell death. The physiological state of ground squirrels subjected to ionizing irradiation at different phases of the hibernation-arousal bout plays a determining role in the changes of the qualitative and quantitative characteristics of blood system cells. Thus, the hypometabolic state of ground squirrels in hibernation is a factor of protection from the action of ionizing radiation on the organism and the immune system.     

Chemoattractant-elicited increases in Dictyostelium myosin phosphorylation are due to changes in myosin localization and increases in kinase activity

We previously reported (Berlot, C. H., Spudich, J. A., and Devreotes, P. N. (1985) Cell 43, 307-314) that cAMP stimulation of chemotactically competent Dictyostelium amoebae causes transient increases in phosphorylation of the myosin heavy chain and 18,000-dalton light chain in vivo and in vitro. In this report we investigate the mechanisms involved in these changes in phosphorylation. In the case of heavy chain phosphorylation, the amount of substrate available for phosphorylation appears to be the major factor regulating the in vitro phosphorylation rate. Almost all heavy chain kinase activity is insoluble in Triton X-100, and the increase in the heavy chain phosphorylation rate in vitro parallels an increase in Triton insolubility of myosin. Changes in heavy chain phosphatase activity are not involved in the changes in the in vitro phosphorylation rate. In the case of light chain phosphorylation, increases in the vitro phosphorylation rate occur under conditions where the amount of substrate available for phosphorylation is constant and phosphatase activity is undetectable, implicating light chain kinase activation as the means of regulation. The specificity of the myosin kinases operating in vivo and in vitro was explored using phosphoamino acid and chymotryptic phosphopeptide analysis. The light chain is phosphorylated on serine both in vivo and in vitro, and phosphopeptide maps of the light chain phosphorylated in vivo and in vitro are indistinguishable. In the case of the heavy chain, both serine and threonine are phosphorylated in vivo and in vitro, although the cAMP-stimulated increases in phosphorylation occur primarily on threonine. Phosphopeptide maps of the heavy chain show that the peptides phosphorylated in vitro represent a major subset of those phosphorylated in vivo. The kinetics of the transient increases in myosin phosphorylation rates observed in vitro can be predicted quantitatively from the in vivo myosin phosphorylation data assuming that there is a constant phosphatase activity.     

广东大中型水库底泥重金属含量特征及潜在生态风险评价

广东省45宗大中型水库底泥重金属含量分析评价结果表明:除Cr外,广东省大中型水库底泥中Cu、Zn、Pb和Cd含量均高于广东省土壤重金属含量背景值.广东省四大地理区域中,粤北地区大中型水库底泥Cu、Zn、Pb和Cd平均含量均为最高,分别为89.71、321.21、154.95mg/kg和1.46mg/kg;其次是粤东和粤中地区;粤西大中型水库底泥Cu、Zn、Pb和Cd平均含量均为最低,但Cr平均含量居四大区域之首,为130.81mg/kg.粤东和粤北大中型水库底泥重金属富集系数以Cd最高;粤中和粤西大中型水库底泥重金属富集系数则以Cu最大.总体而言,粤北大中型水库底泥重金属具有很强的潜在生态风险,粤东和粤中大中型水库底泥重金属潜在生态风险程度为中等;粤西大中型水库底泥重金属属于轻微生态风险程度.结果说明,广东省大部分地区大中型水库底泥的重金属潜在生态风险主要是由于底泥中Cd的潜在生态风险系数过高所造成.人为生产活动,特别是矿产开采造成的污染是广东省大中型水库底泥重金属潜在生态风险等级提高的主要原因.     

The role of protein synthesis during metabolic depression in the Australian desert frog Neobatrachus centralis

Little is known about the role of energy consuming processes during metabolic depression. We have shown that aestivation in the Australian desert frog Neobatrachus centralis is accompanied by an in vivo metabolic depression of 77%. Using an in vitro liver slice preparation, we have measured an in vitro metabolic depression in liver of 55%, with a concomitant 67% decrease in the rate of protein synthesis. The decrease in protein synthesis accounts for 52% of the metabolic depression of the tissue, but only 4.9% of the metabolic depression of the whole animal. No in vitro metabolic depression or decrease in protein synthesis during aestivation was measured in muscle, but a decrease in the low rate of protein synthesis in muscle in vivo could not, in any case, account for more than 3% of the metabolic depression of the whole animal. The liver, although not a quantitatively important tissue in terms of metabolic depression in vivo, offers the opportunity to characterise the regulation of protein synthesis in a system in which metabolic depression is not confounded by changes in ambient temperature and PO2.     

Immunohistochemical localization of a thyroid hormone-binding protein (p55) in human tissues

We have localized p55, a thyroid hormone-binding protein found in the endoplasmic reticulum in cultured cells, in samples of normal human and monkey tissues, using a monoclonal antibody with cryostat sections and immunoperoxidase histochemistry. Large amounts of p55 were found in many tissues, generally corresponding to the amount of endoplasmic reticulum contained in each cell type. Intense localization of p55 was found in cells of the anterior and intermediate pituitary lobes, in epithelial cells of thyroid follicles, in the glandular epithelium of mammary gland, in hepatocytes, in Paneth cells and Brunner's glands in duodenum, in acinar cells of pancreas, in adrenal cortical cells, and in scattered interstitial fibroblastic cells in many tissues. These results suggest a potential role for thyroid hormone and p55 in regulating protein synthesis or secretion in multiple organs.