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1.
To clarify the changes of mineral levels in different tissues of riboflavin-deficient rats, Wistar rats were separated into three groups. One group was fed a diet ad libitum that was deficient in riboflavin. The other two were fed either the complete diet that was weight-matched to the riboflavin-deficient group or fed a complete diet ad libitum. In riboflavin-deficient rats, the hemoglobin concentration and riboflavin contents of blood, liver, and kidney were significantly decreased, compared with weight-matched and ad libitum-fed controls. The mineral concentrations of tissues are summarized as follows: The iron (Fe) concentration in the heart, liver, and spleen was decreased in the riboflavin-deficient group compared with the other groups. Calcium (Ca) and magnesium (Mg) concentrations in tibia were decreased in the riboflavin-deficient group compared with the other two groups. Copper (Cu) concentration was increased in the heart and liver when the riboflavin-deficient group was compared with the other groups. Zinc (Zn) concentration was increased in tibia when the riboflavin-deficient group was compared with the other groups.  相似文献   

2.
Immunolocalization of AQP9 in liver, epididymis, testis, spleen, and brain   总被引:18,自引:0,他引:18  
The aims of this study were to determine the cellular and subcellular localization of aquaporin-9 (AQP9) in different rat organs by immunoblotting, immunohistochemistry and immunoelectron microscopy. To analyze this, we used rabbit antibodies to rat AQP9 raised against three different AQP9 peptides (amino acids 267-287, 274-295, and 278-295). In Cos7 cells transfected with rat AQP9, the affinity-purified antibodies exhibited marked labeling, whereas nontransfected cells and cells transfected with aquaporin-8 (AQP8) exhibited no labeling, indicating the specificity of the AQP9 antibodies. Immunoblotting revealed a predominant band of 28 kDa in membranes of total rat liver, epididymis, testes, spleen, and brain. Preabsorption with the immunizing peptides eliminated the labeling. Immunohistochemistry showed strong anti-AQP9 labeling in liver hepatocytes. The labeling was strongest at the sinusoidal surface, and there was little intracellular labeling. Immunoelectron microscopy revealed that the labeling was associated with the plasma membrane of the hepatocytes. In testes Leydig cells exhibited anti-AQP9 labeling, and in epididymis, the stereocilia of the ciliated cells (principal cells) exhibited significant labeling, whereas there was no labeling of the nonciliated cells (basal cells). This was confirmed by immunoelectron microscopy. In spleen strong labeling of cells was observed of leukocytes in the red pulp, whereas there was no labeling of cells in the white pulp. In rat brain, AQP9 immunolabeling was confined to ependymal cells lining the ventricles and to the tanycytes of the mediobasal hypothalamus. Antibody preabsorbed with the immunizing peptide revealed no labeling. In conclusion, AQP9 proteins is strongly expressed in rat liver, testes, epididymis, spleen, and brain.  相似文献   

3.
The concentrations of the trace elements Cd, Hg, Pb, and Se during the perinatal period in human placenta and in the blood of the mother and the newborn (cord blood) were determined. Breast milk (colostrum and mature milk) was also included to permit correlations between the different compartments. For Cd, a placental barrier exists, in accord with previous observations. For Pb, a strong correlation between the concentrations in the blood of the mother and of the newborn was found. The concentration of Hg was in most cases below low the detection limit. Its concentration in colostrum was higher than in the mature milk. The results for Se reflect the knowledge about an essential trace element. Strong positive correlations were noted between maternal blood and cord blood and maternal milk. Anodic stripping voltammetry (DPASV) was used for the determination of Cd and Pb, cold vapor AAS (CVAAS) for the determination of Hg, and instrumental neutron activation analysis (INAA) for the determination of Se.  相似文献   

4.
The aim of this study was to assess the hair copper concentration in a population of healthy children, teenagers, and adults living in a specific region of Poland. For this purpose, 840 healthy individuals aged 1–50 yr living in Szczecin, Poland were selected for the study. They were divided into subgroups according to age and sex and the hair was analyzed for copper using a standard atomic absorption spectrometric technique. The level of copper was highest for the group including 11–15 yr old. In the other subgroups, the concentration of copper was lower than the values considered normal, suggesting the possibility of endemic copper deficiency in the inhabitants of this region.  相似文献   

5.
To clarify the seroepidemiology of human parechovirus type 1 (HPeV1), 3 and 6, neutralizing antibodies (NT Abs) were measured in 214 serum specimens collected in 2014 in Yamagata, Japan. The seroprevalence against HPeV1 was 100% in all age groups, while that against HPeV3 and HPeV6 was 79.4% and 66.8%, respectively, overall. The geometric mean titers of NT Abs against HPeV1, 3 and 6 were 755.2, 255.0 and 55.9, respectively, overall. Our findings indicate that HPeV1 is the most prevalent HPeV circulating in Yamagata, followed by HPeV3 and HPeV6.  相似文献   

6.
The problem of the transformation of specific antibodies into nonspecific polyreactive immunoglobulins (PRIG) was considered. On the basis of the obtained data the conclusion has been made that this process can occur not only in vitro, but also in vivo. The biological consequences of such a transformation of circulated specific antibodies into PRIG or increase of PRIG reactivity because of their unblocking are discussed. It was supposed that PRIG was able to play positive role in the defence of organisms against some infections. Meanwhile, disregulation of the PRIG production in vivo can, probably, lead to their participation in induction and/or in aggravation of some danger diseases, such as autoimmune diseases, atherosclerosis, infarct, stroke, and cancer. If so, farther investigation of PRIG involvement in these pathological processes could open new ways for their curing or even prophylaxis.  相似文献   

7.
Calmodulin-dependent protein kinase II (CaMKII) has been proposed to be a therapeutic target for heart failure (HF). However, the cardiac effect of chronic CaMKII inhibition in HF has not been well understood. We have tested alterations of Ca(2+) handling, excitation-contraction coupling, and in vivo β-adrenergic regulation in pressure-overload HF mice with CaMKIIδ knockout (KO). HF was produced in wild-type (WT) and KO mice 1 wk after severe thoracic aortic banding (sTAB) with a continuous left ventricle (LV) dilation and reduction of ejection fraction for up to 3 wk postbanding. Cardiac hypertrophy was similar between WT HF and KO HF mice. However, KO HF mice manifested exacerbation of diastolic function and reduction in cardiac reserve to β-adrenergic stimulation. Compared with WT HF, L-type calcium channel current (I(Ca)) density in KO HF LV was decreased without changes in I(Ca) activation and inactivation kinetics, whereas I(Ca) recovery from inactivation was accelerated and Ca(2+)-dependent I(Ca) facilitation, a positive staircase blunted in WT HF, was recovered. However, I(Ca) response to isoproterenol was reduced. KO HF myocytes manifested dramatic decrease in sarcoplasmic reticulum (SR) Ca(2+) leak and slowed cytostolic Ca(2+) concentration decline. Sarcomere shortening was increased, but relaxation was slowed. In addition, an increase in myofilament sensitivity to Ca(2+) and the slow skeletal muscle troponin I-to-cardiac troponin I ratio and interstitial fibrosis and a decrease in Na/Ca exchange function and myocyte apoptosis were observed in KO HF LV. CaMKIIδ KO cannot suppress severe pressure-overload-induced HF. Although cellular contractility is improved, it reduces in vivo cardiac reserve to β-adrenergic regulation and deteriorates diastolic function. Our findings challenge the strategy of CaMKII inhibition in HF.  相似文献   

8.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

9.
Males of the seaweed pipefish, Syngnathus schlegeli, take care of their eggs in the brood pouch. These pipefish were periodically collected from the shallow seagrass beds in Otsuchi Bay on the Pacific coast of northern Honshu, Japan, from spring to autumn to investigate the basic reproductive ecology. Appearance of the pipefish in the coastal seagrass beds coincided with the initiation of reproduction. The reproductive season was from May to at least October, with its peak in July. A rearing experiment revealed that the brooding period of the male had a negative correlation with water temperature, and it was estimated to last about 1 month in the bay. Almost all males were brooding during the peak of the reproductive season. Although, the brood pouch of most males was either full or devoid of eggs, 6.2% of the males had a partially filled (20%–90%) brood pouch, and multiple clutches were identified in the brood pouch of some males, indicating that the mating system of the pipefish is polygamous, perhaps polygynous. Sex ratio fluctuated among months, and the overall sex ratio tended to be biased to male. Body size of males with an immature brood pouch had a wide range, from 133 to 215 mm standard length (SL). The smallest brooding male was 134 mm SL. Mean SL of brooding males was significantly larger than that of nonbrooding mature males. The number of males with an immature brood pouch was greater at the beginning than later in the reproductive season. The results seem to collectively indicate that the occurrence of a larger proportion of immature males at the onset of the reproductive season may be ascribed to both new recruitment and larger body size at maturation, resulting from the males trading the reproductive effort to somatic growth, perhaps to increase future reproductive success. Received: April 4, 2000 / Revised: September 21, 2000 / Accepted: January 16, 2001  相似文献   

10.
Thiobacillus novellus was able to grow with oxalate, formate, formamide, and methanol as sole sources of carbon and energy. Extensive growth on methanol required yeast extract or vitamins. Glyoxylate carboligase was detected in extracts of oxalate-grown cells. Ribulose bisphosphate carboxylase was found in extracts of cells grown on formate, formamide, and thiosulfate. These data indicate that oxalate is utilized heterotrophically in the glycerate pathway, and formate and formamide are utilized autotrophically in the ribulose bisphosphate pathway. Nicotinamide adenine dinucleotide-linked formate dehydrogenase was present in extracts of oxalate-, formate-, formamide-, and methanol-grown cells but was absent in thiosulfate- and acetate-grown cells.  相似文献   

11.
Pregnant women in developing countries are vulnerable to multiple micronutrient deficiencies. Studies assessing serum levels of the micronutrients and magnitude of their deficiencies are very scarce in African subjects. This study was aimed at determining serum levels of micronutrients in 375 pregnant (42 HIV seropositive) and 76 non-pregnant women (20 HIV seropositive) who visited the University of Gondar Hospital, Gondar, Ethiopia. Serum concentrations of zinc,\ copper, selenium, calcium, and magnesium were determined using an inductively coupled plasma mass spectrometer. Irrespective of HIV serostatus, pregnant women had significantly higher serum concentrations of copper and copper/zinc ratio and significantly lower magnesium compared to those in non-pregnant women (P < 0.05). Except for selenium, which was significantly lower in HIV-seropositive pregnant women (P < 0.05), the mean serum concentrations of zinc, copper, calcium, and magnesium were not significantly different between pregnant women by HIV serostatus. The prevalence of deficiency in zinc, magnesium, selenium, and calcium in the pregnant women, irrespective of their HIV serostatus, was 66.7%, 25.6%, 21.9%, and 9.3%, respectively. The magnitude of deficiency in zinc, magnesium, and selenium was significantly higher in HIV seropositive pregnant women (76.2%, 52.4%, and 45.2%) than that in HIV-seronegative pregnant women (65.5%, 22.2%, and 18.9%) and in HIV-seronegative non-pregnant women (42.9%, 8.1%, and 30.4%; P < 0.05). Deficiency in one, two, three, or four mineral elements was observed in 44.8%, 14.4%, 9.9%, and 5.1% of the pregnant women, respectively. Only 25.9% of the pregnant women and 44.7% of the non-pregnant women were not deficient in any of the micronutrients. The high prevalence of micronutrient deficiencies in pregnant and non-pregnant women in Gondar, Ethiopia warrants the need for strategies on prevention and control of the deficiencies.  相似文献   

12.
Redistribution of Potassium, Calcium, Magnesium, and Manganese in the Plant   总被引:2,自引:0,他引:2  
The extent of redistribution in apple was described by calculating the fruit/leaf ratio of the cation content. It was found that the redistribution diminishes in the sequence K > Mg > Ca ~ Mn. These results are more or less in agreement with those found elsewhere. Investigations were made to see whether it was possible to account for the differences in redistribution by the phloem by means of the solubility of these cations in the sieve tube sap. As model plants Yucca flaccida and Ricinus communis were used, plants from which it was possible to obtain phloem sap in a rather pure state. It was found that the addition of potassium and magnesium as a chloride in the usual investigated range of concentrations did not give precipitation. With calcium and manganese, however, a precipitate soon occurred. Manganese was demonstrated to be less soluble than calcium. For Ricinus the maximum amount of calcium and manganese the sieve tube sap could contain before precipitation set in was higher than for Yucca sap. The results confirm the possibility that the redistribution of the different cations in the plant can be related inter alia to their solubility in the sieve tube sap. It was also found that the calcium in the phloem sap is present in ionic condition. Thus the normal laws of solubility should be applicable.  相似文献   

13.
PROJECT: Wilson's disease (WD) is an inherited disorder of copper metabolism characterised by juvenile liver cirrhosis and by neurological symptoms. Copper levels in brain in WD have been reported to be 10 to 15 fold normal values, depending on the different brain regions. Being very few data on copper distribution in central nervous system in WD available, it seemed of interest to study the concentration of copper and of other trace elements (Zn, P, Mg, Ca, Fe and S) in the brain of a patient died for WD. PROCEDURE: a 56 year old woman affected by WD was admitted to our hospital with signs of hepatic failure and died few days later. At autopsy, a brain slice extending from the left to the right hemisphere was divided in 28 samples. On each sample Copper, Iron, Magnesium, Phosphorus, Sulphur, Zinc and Calcium were determined by Induced Coupled Plasma Atomic Emission Spectroscopy. RESULTS: the mean concentration of copper, ranging from 88 to 158 microg/g of dry tissue in all the brain specimens was higher than literature reference values, while that of the other tested elements was considerably lower. CONCLUSIONS: 1) In the brain of WD patient examined the status of trace elements was extensively altered. Further studies are necessary to correlate the concentration of trace elements with pathological lesions and with clinical pictures. 2) The elements considered in our study showed an uneven distribution in different brain areas.  相似文献   

14.
Polyamine transport,accumulation, and release in brain   总被引:3,自引:0,他引:3  
Cycling of polyamines (spermine and spermidine) in the brain was examined by measuring polyamine transport in synaptic vesicles, synaptosomes and glial cells, and the release of spermine from hippocampal slices. It was found that membrane potential-dependent polyamine transport systems exist in synaptosomes and glial cells, and a proton gradient-dependent polyamine transport system exists in synaptic vesicles. The glial cell transporter had high affinities for both spermine and spermidine, whereas the transporters in synaptosomes and synaptic vesicles had a much higher affinity for spermine than for spermidine. Polyamine transport by synaptosomes was inhibited by putrescine, agmatine, histidine, and histamine. Transport by glial cells was also inhibited by these four compounds and additionally by norepinephrine. On the other hand, polyamine transport by synaptic vesicles was inhibited only by putrescine and histamine. These results suggest that the polyamine transporters present in glial cells, neurons, and synaptic vesicles each have different properties and are, presumably, different molecular entities. Spermine was found to be accumulated in synaptic vesicles and was released from rat hippocampal slices by depolarization using a high concentration of KCl. Polyamines, in particular spermine, may function as neuromodulators in the brain.  相似文献   

15.
A survey was undertaken in Tigray, Northern Ethiopia, to assess the prevalence of malaria, schistosomiasis, and intestinal helminths in relation to microdams. The survey took place from March to June 1995, during the dry season, at 41 microdams. At each site the village nearest the dam (within thirty minutes walk) was selected, ten households were randomly chosen, and all family members were examined for malaria and intestinal parasites. The overall study sample was 2271 people, of all age groups. Plasmodium falciparum infection was documented in four villages (at 10% of microdams); prevalence was 1.2% (range 0-20% by village). Larvae of Anopheles gambiae s.l. were found at one microdam. Infection with intestinal schistosomiasis was documented in 20 villages (at 49% of microdams), and one third of those infected had moderate to heavy infections. Biomphalaria species, the intermediate host snails of Schistosoma mansoni, were found at 16 microdams (39%), and snails infected by mammalian cercariae were found in one locality. Infections with soil-transmitted nematodes were prevalent: hookworm was detected in more than two thirds of the villages, and Ascaris lumbricoides and Trichuris trichiura were present in almost half of the villages. Out of 2078 stool examinations, the prevalence of S. mansoni infection was 7.2% (range 0-48% by village), of A. lumbricoides 2.3% (range 0-31%), of T. trichiura 2.4% (range 0-21%), and of hookworm 8.9% (range 0-78%). The prevalence of malaria, S. mansoni and hookworm was higher at altitudes below 2000 metres above sea level. S. mansoni was more prevalent in microdams built more than 5 years before the survey, while T. trichiura was more prevalent at recently constructed microdams. The widespread distribution of schistosomiasis and intestinal helminths, and the presence of malaria infection during the dry season confirm that microdams create favourable conditions for the transmission of these parasitic diseases. Health safeguards must be incorporated into the planning, construction, and operation of microdams and irrigation systems in order to prevent or reduce these diseases. In areas with high prevalence, control activities should be intensified.  相似文献   

16.
Pret'ová A  Obert B  Bartosová Z 《Protoplasma》2006,228(1-3):107-114
Summary. The article is reviewing some significant features and issues in the process of haploid formation in two important monocotyledonous crop plants – maize and barley – and in two dicotyledonous plants – flax and potato. Exotic maize lines with higher androgenic response turned up as a good source for this heritable trait and this valuable trait can be incorporated into elite maize lines via crossing. Lots of attempts were devoted to identifying some cytological and/or morphological markers for androgenic response in maize microspore cultures. The “starlike” organization of the cytoplasm inside the induced maize microspores together with the enlarged size of induced microspores can be considered as morphological markers for androgenic response. In barley, microspores with rich cytoplasm that was of granular appearance with the nucleus located near the cell wall and with no visible vacuole had the largest survival rate and many of these cells continued in development and produced embryos. In flax, a dramatic increase of induction rate in anther cultures (up to 25%) was achieved when flax anthers were pretreated for 3 days at 4 °C and afterwards kept for 1 day at 35 °C. Also gynogenesis in flax has been reported already and complete plants were obtained. In potato microspore cultures, formation of two dissimilar cells indicated a strong polarization in the system and as a result of this polarization a prominent suspensor developed that persisted until the torpedo stage of the androgenic embryo. This was the first time the formation of a well developed suspensor was described in connection with androgenesis. Correspondence and reprints: Institute of Plant Genetics and Biotechnology, Slovak Academy of Sciences, P.O. Box 39A, 950 07 Nitra, Slovak Republic.  相似文献   

17.
The concentration of fluoride and nitrate in groundwater is usually higher than that of surface water. The main objective of this study was to estimate the health-risk assessment associated with fluoride, nitrate, and nitrite in drinking water in Sanandaj and its villages. The number of samples in the Sanandaj and its rural was 106. The average concentration of fluoride in urban and rural drinking water was 0.22 mg/l and 0.27 mg/l, respectively. Fluoride concentration was also close to urban and rural drinking water. The concentration of nitrate in urban and rural drinking water was in the range between 0.28–27.77 mg/l and 1.28–80 mg/l, respectively. The concentration of nitrate reported in rural samples was higher than that of urban samples. The maximum concentration of nitrate reported in this study was 80 mg/l. The mean CDI for nitrate in the men, women, and children was 0.4258, 0.5110, and 1.1454, respectively. The findings of this study indicated that all three groups studied were exposed to nitrate contact hazards (HQ > 1). Therefore, the HQ in each of the three groups was higher than 1, which should be carefully monitored and necessary measures should be performed.  相似文献   

18.
Gu X  Wang P  Liu D  Lv C  Lu Y  Zhou Z 《Chirality》2008,20(2):125-129
The stereoselective degradation of the racemic benalaxyl in vegetables such as tomato, tobacco, sugar beet, capsicum, and the soil has been investigated. The two enantiomers of benalaxyl in the matrix were extracted by organic solvent and determined by validated chiral high-performance liquid chromatography with a cellulose-tris-(3, 5-dimethylphenylcarbamate)-based chiral column. Rac-benalaxyl was fortified into the soil and foliar applied to vegetables. The assay method was linear over a range of concentrations (0.5-50 microg ml(-1)) and the mean recoveries in all the samples were more than 70% for the two enantiomers. The limit of detection for both enantiomers was 0.05 microg g(-1). The results in soil showed that R-(-)-enantiomer dissipated faster than S-(+)-enantiomer and the stereoselectivity might be caused by microorganisms. In tomato, tobacco, sugar, beet, and capsicum plants, there was significantly stereoselective metabolism. The preferential absorption and degradation of S-(+)-enantiomer resulted an enrichment of the R-(-)-enantiomer residue in all the vegetables.  相似文献   

19.
Genes that modulate the action of hormones and cytokines play a critical role in stress response, survival, and in growth and differentiation of cells. Many of these biological response modifiers are responsible for various pathological conditions, including inflammation, infection, cachexia, aging, genetic disorders, and cancer. We have previously identified a new gene, BRE, that is responsive to DNA damage and retinoic acid. Using multiple-tissue dot-blotting and Northern blotting, BRE was recently found to be strongly expressed in adrenal cortex and medulla, in testis, and in pancreas, whereas low expression was found in the thyroid, thymus, small intestine and stomach. In situ hybridization and immunohistochemical staining indicated that BRE was strongly expressed in the zona glomerulosa of the adrenal cortex, which synthesizes and secretes the mineralocorticoid hormones. It is also highly expressed in the glial and neuronal cells of the brain and in the round spermatids, Sertoli cells, and Leydig cells of the testis, all of which are associated with steroid hormones and/or TNF synthesis. However, BRE expression was downregulated in human adrenal adenoma and pheochromocytoma, whereas its expression was enhanced in abnormal adrenal tissues of rats chronically treated with nitrate or nitrite. These data, taken together, indicate that the expression of BRE is apparently associated with steroids and/or TNF production and the regulation of endocrine functions. BRE may play an important role in the endocrine and immune system, such as the cytokine-endocrine interaction of the adrenal gland.  相似文献   

20.
Twenty-seven sheep were used in two experiments to study the distribution of copper (Cu), zinc (Zn), and iron (Fe) in the kidney cytosol of control, Cu-loaded, and thiomolybdate (TM)-treated sheep. A comparison was made of the patterns of distribution on Sephadex G-75 of Cu, Zn, and Fe from the cytosol of fresh and frozen kidneys and after thawing of frozen cytosol. In both Cu-dosed and TM-treated sheep, the absolute level of Cu increased in the cytosol, but the percent of Cu decreased. The percent recovery of Cu from the frozen kidney was comparable to that from fresh kidney, but the extraction of Cu from the supernatant of frozen cytosol was approximately 10% less. This was due to a loss of Cu in a precipitate that formed when the frozen cytosol was thawed. Most of the Cu in the cytosol from the kidney of Cu-loaded sheep was in a metallothionein (MT)-like protein fraction and was trichloroacetic acid (TCA) soluble. In contrast, that from the cytosol of TM-treated sheep was mostly in a high molecular weight fraction that was TCA insoluble. The chromatograms obtained from cytosol derived from frozen kidneys, or cytosol that had itself been frozen, contained a similar distribution of Cu, Zn, and Fe, but the peak heights were lower in the latter samples.  相似文献   

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