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101.
The effect of external Ca2+ and Ca2+ -channel modulators on the phytochrome-controlled swelling of etiolated wheat ( Triticum aestivum L. cv. Arminda) mesophyll protoplasts has been studied. The red light (R)-stimulated swelling of the protoplasts requires Ca2+ in the surrounding medium and maximum response was observed in a medium containing I m M CaCI2 . Far-red light (FR) irradiation of protoplasts in the presence or absence of Ca2+ does not influence the protoplast volume. The Ca2+ -channel antagonist nifedipine prevents R-induced protoplast swelling at very low concentrations (0.1 μ M ). The Ca2+ -channel agonist Bay K-8644 stimulates the swelling of protoplasts incubated in darkness or irradiated with FR. Action of nifedipine depends on whether it is applied before or after the R pulse. The results are compatible with the hypothesis that phytochrome controls the activity of dihydropyridine-sensitive L-type Ca2+ channels. 相似文献
102.
The red light (R)-induced swelling of mesophyll protoplasts, isolated from dark-grown wheat ( Triticum aestivum L. cv. Arminda) leaves, was inhibited by guanosine-5'-0-(2-thiodiphosphate) (GDP-β-S). In darkness or after control irradiation with far-red light (FR), guanosine-5'-O-(3-thiotriphosphate) (GTP-γ-S) induced swelling to the same extent as after R. Both GDP-β-S and GTP-γ-S were introduced into the cytoplasm by means of electroporation. The possibility of R-induced activation of the phosphatidylinositol pathway of transmembrane signalling was investigated. Neomycin, Li+ and l-(5-isoquinolinesulfonyl)-2-methylpiperazine (H7 ) inhibited the R-induced swelling. Phorbol 12-myristate 13-acetate (PMA) induced swelling after control irradiation with FR. Neomycin and Li+ also inhibited GTP-γ-S-induced swelling. These results suggest that a GTP-binding protein is involved in the phytochrome-regulated swelling response. Addition of N6 , 2'-0-dibutyryladenosine 3':5'-cyclic monophosphate (DB-cAMP) induced swelling to the same extent as R-irradiation. The calmodulin antagonist N-(6-aminohexyl)5-chloro-l-naphthalenesulfonamide (W7 ) induced swelling after FR, while R-induced swelling was not affected. The less active analogue N-(6-aminohexyl)-l-naphthalenesulfonamide (W5 ) induced no swelling after FR. It is speculated that the protoplast volume is correlated with the cytoplasmic concentration of free Ca2+ . 相似文献
103.
Roelof Docter Eric P. Krenning Greetje Bos Durk F. Fekkes George Hennemann 《The Biochemical journal》1982,208(1):27-34
We investigated 3,3′,5-tri-iodo-l-thyronine transport by human erythrocytes and by `ghosts'' prepared from these cells. Uptake of tri-iodothyronine by erythrocytes at 37°C was time-dependent with a maximum reached after 60min. Tracer analysis after incubation for 1min revealed only one saturable binding site, with Km 128±19nm (mean±s.e.m.; n=7) and Vmax. 4.6±0.7pmol of tri-iodothyronine/min per 6×107 cells. After 10min incubation Km 100±16nm (n=10) was found with Vmax. 7.7±1.2pmol of tri-iodothyronine/10min per 6×107 cells. At 0°C the uptake system is still active, with Km 132±26nm and Vmax. 1.8±0.3pmol of tri-iodothyronine/10min per 6×107 cells. The Vmax. with intact cells is 5-fold greater than the Vmax. with membranes derived from the same amount of cells when uptake studies are performed in media with similar free tri-iodothyronine concentrations. This indicates that at least 80% of tri-iodothyronine taken up by the intact erythrocytes enters the cell. This saturable uptake system can be inhibited by X-ray-contrast agents in a dose-dependent fashion. (±)-Propranolol, but not atenolol, has the same effect, indicating that the membrane-stabilizing properties of (±)-propranolol are involved. Furthermore, there is no inhibition by ouabain or vanadate, which indicates that tri-iodothyronine uptake is not dependent on the activity of Na++K+-dependent adenosine triphosphatase. We have prepared erythrocyte `ghosts'', resealed after 2.5min with 0mm-, 2mm- or 4mm-ATP inside. Inclusion of ATP and integrity of the membrane of the erythrocyte `ghosts'' were verified on the basis of an ATP-concentration-dependent functioning of the Ca2+ pump. No difference was found in the uptake of tri-iodothyronine by erythrocyte `ghosts'' with or without ATP included, indicating that uptake of tri-iodothyronine is not ATP-dependent. The following conclusions are drawn. (1) Tri-iodothyronine enters human erythrocytes. (2) There is only one saturable uptake system present for tri-iodothyronine, which is neither energy (i.e. ATP)-dependent nor influenced by the absence of an Na+ gradient across the plasma membrane. This mode of uptake of tri-iodothyronine by human erythrocytes is in sharp contrast with that of rat hepatocytes, which uptake system is energy-dependent and ouabain-sensitive [Krenning, Docter, Bernard, Visser & Hennemann (1978) FEBS Lett. 91, 113–116; Krenning, Docter, Bernard, Visser & Hennemann (1980) FEBS Lett. 119, 279–282]. (3) X-ray-contrast agents inhibit tri-iodothyronine uptake by erythrocytes in a similar fashion to that by which they inhibit the uptake of tri-iodothyronine by rat hepatocytes [Krenning, Docter, Bernard, Visser & Hennemann (1982) FEBS Lett. 140, 229–233]. 相似文献
104.
Estimating treatment coverage for people with substance use disorders: an analysis of data from the World Mental Health Surveys 下载免费PDF全文
Louisa Degenhardt Meyer Glantz Sara Evans‐Lacko Ekaterina Sadikova Nancy Sampson Graham Thornicroft Sergio Aguilar‐Gaxiola Ali Al‐Hamzawi Jordi Alonso Laura Helena Andrade Ronny Bruffaerts Brendan Bunting Evelyn J. Bromet José Miguel Caldas de Almeida Giovanni de Girolamo Silvia Florescu Oye Gureje Josep Maria Haro Yueqin Huang Aimee Karam Elie G. Karam Andrzej Kiejna Sing Lee Jean‐Pierre Lepine Daphna Levinson Maria Elena Medina‐Mora Yosikazu Nakamura Fernando Navarro‐Mateu Beth‐Ellen Pennell José Posada‐Villa Kate Scott Dan J. Stein Margreet ten Have Yolanda Torres Zahari Zarkov Somnath Chatterji Ronald C. Kessler 《World psychiatry》2017,16(3):299-307
Substance use is a major cause of disability globally. This has been recognized in the recent United Nations Sustainable Development Goals (SDGs), in which treatment coverage for substance use disorders is identified as one of the indicators. There have been no estimates of this treatment coverage cross‐nationally, making it difficult to know what is the baseline for that SDG target. Here we report data from the World Health Organization (WHO)'s World Mental Health Surveys (WMHS), based on representative community household surveys in 26 countries. We assessed the 12‐month prevalence of substance use disorders (alcohol or drug abuse/dependence); the proportion of people with these disorders who were aware that they needed treatment and who wished to receive care; the proportion of those seeking care who received it; and the proportion of such treatment that met minimal standards for treatment quality (“minimally adequate treatment”). Among the 70,880 participants, 2.6% met 12‐month criteria for substance use disorders; the prevalence was higher in upper‐middle income (3.3%) than in high‐income (2.6%) and low/lower‐middle income (2.0%) countries. Overall, 39.1% of those with 12‐month substance use disorders recognized a treatment need; this recognition was more common in high‐income (43.1%) than in upper‐middle (35.6%) and low/lower‐middle income (31.5%) countries. Among those who recognized treatment need, 61.3% made at least one visit to a service provider, and 29.5% of the latter received minimally adequate treatment exposure (35.3% in high, 20.3% in upper‐middle, and 8.6% in low/lower‐middle income countries). Overall, only 7.1% of those with past‐year substance use disorders received minimally adequate treatment: 10.3% in high income, 4.3% in upper‐middle income and 1.0% in low/lower‐middle income countries. These data suggest that only a small minority of people with substance use disorders receive even minimally adequate treatment. At least three barriers are involved: awareness/perceived treatment need, accessing treatment once a need is recognized, and compliance (on the part of both provider and client) to obtain adequate treatment. Various factors are likely to be involved in each of these three barriers, all of which need to be addressed to improve treatment coverage of substance use disorders. These data provide a baseline for the global monitoring of progress of treatment coverage for these disorders as an indicator within the SDGs. 相似文献
105.
Immunohistochemical analysis of the distribution of histone H5 and hemoglobin during chicken development 总被引:1,自引:0,他引:1
Antoon F.M. Moorman Margreet P.A. Schalekamp Piet A.J. de Boer Willie J.C. Geerts Wouter H. Lamers Rob Charles 《Differentiation; research in biological diversity》1987,34(3):161-167
We used immunohistochemical procedures to investigate embryonic erythropoiesis in serial sections of chicken embryos after 2-13 days of incubation. Antibodies specific for the erythrocyte-specific histone H5, for embryonic hemoglobin, and for adult hemoglobin were used as markers for general, primitive, and definitive erythropoiesis, respectively. Histone H5 was present in erythrocytes at all of the stages studied, i.e., in both the primitive and definitive cells. Cell of the definitive lineage were first detected, at about 5-6 days of incubation, in erythroid foci in the mesenchyme around the vitelline stalk. At 7-9 days of incubation, a massive mesenchymal conglomeration of erythropoietic cells developed, extending from the cervical to the abdominal region and ventrally to the vertebral body, with its largest extensions being around the arteries in the mediastinum. Immunostaining revealed that these erythroid cells belonged to the definitive erythropoietic lineage. These cells had disappeared completely after 12 days of incubation, i.e., before erythropoiesis is visible in the bone marrow. These observations are consistent with the notion that the yolk sac is essential for the formation of the definitive erythroid lineage. 相似文献
106.
107.
Anne F. Voor in 't holt Juli?tte A. Severin Wil H. F. Goessens René te Witt Margreet C. Vos 《PloS one》2015,10(8)
Background
Infections with multidrug-resistant (MDR) microorganisms are an increasing threat to hospitalized patients. Although rapid typing of MDR microorganisms is required to apply targeted prevention measures, technical barriers often prevent this. We aimed to assess whether extended-spectrum beta-lactamase (ESBL)-producing Klebsiella species are transmitted between patients and whether routine, rapid typing is needed.Methods
For 43 months, the clonality of all ESBL-producing Klebsiella isolates from patients admitted to Erasmus MC University Medical Center in Rotterdam, the Netherlands was assessed with Raman spectroscopy. A cluster was defined as n ≥2 patients who had identical isolates. Primary patients were the first patients in each cluster. Secondary patients were those identified with an isolate clonally related to the isolate of the primary patient.Results
Isolates from 132 patients were analyzed. We identified 17 clusters, with 17 primary and 56 secondary patients. Fifty-nine patients had a unique isolate. Patients (n = 15) in four out of the 17 clusters were epidemiologically related. Ten of these 15 patients developed an infection.Conclusions
Clonal outbreaks of ESBL-producing Klebsiella species were detected in our hospital. Theoretically, after Raman spectroscopy had detected a cluster of n ≥2, six infections in secondary patients could have been prevented. These findings demonstrate that spread of ESBL-producing Klebsiella species occurs, even in a non-outbreak setting, and underscore the need for routine rapid typing of these MDR bacteria. 相似文献108.
Margreet W. Harskamp-van Ginkel Stephanie J. London Maria C. Magnus Maaike G. Gademan Tanja G. Vrijkotte 《PloS one》2015,10(10)
Background
A causal relationship between maternal obesity and offspring asthma is hypothesized to begin during early development, but no underlying mechanism for the found association is identified. We quantitatively examined mediation by offspring body mass index (BMI) in the association of maternal pre-pregnancy BMI on risk of asthma and wheezing during the first 7–8 years of life in a large Amsterdam born birth cohort.Methods
For 3185 mother-child pairs, mothers reported maternal pre-pregnancy BMI and offspring outcomes “ever being diagnosed with asthma” and “wheezing in the past 12 months” on questionnaires. We measured offspring height and weight at age 5–6 years. We performed a multivariate log linear regression comparing outcomes in offspring of mothers with different BMI categories. For each category we quantified and tested mediation by offspring BMI and also investigated interaction by parental asthma.Results
At the age of 7–8 years, 8% of the offspring ever had asthma and 7% had current wheezing. Maternal pre-pregnancy obesity was associated with higher risks of asthma (adjusted RR 2.32 (95% CI: 1.49–3.61) and wheezing (adjusted RR 2.16 (95% CI: 1.28–3.64). Offspring BMI was a mediator in the association between maternal BMI and offspring wheezing, but not for asthma. There was no interaction by parental asthma.Conclusions
Maternal pre-pregnancy obesity was associated with higher risks of offspring asthma and wheezing. The association between maternal obesity and offspring wheezing was both direct and indirect (mediated) through the child’s own BMI. 相似文献109.
Akimoto Y Miura Y Toda T Wolfert MA Wells L Boons GJ Hart GW Endo T Kawakami H 《Clinical proteomics》2011,8(1):15
Purpose
The objective of the present study is to identify proteins that change in the extent of the modification with O-linked N-acetylglucosamine (O-GlcNAcylation) in the kidney from diabetic model Goto-Kakizaki (GK) rats, and to discuss the relation between O-GlcNAcylation and the pathological condition in diabetes. 相似文献110.
The overexpression of saccharides such as Globo-H, Lewis(Y) and Tn antigen is a common feature of oncogenic transformed cells. Endeavors to exploit this aberrant glycosylation for cancer vaccine development have been complicated by difficulties in eliciting high titers of IgG antibodies against classical conjugates of tumor-associated carbohydrates to carrier proteins. We have designed, chemically synthesized and immunologically evaluated a number of fully synthetic vaccine candidates to establish strategies to overcome the poor immunogenicity of tumor-associated carbohydrates and glycopeptides. We have found that a three-component vaccine composed of a TLR2 agonist, a promiscuous peptide T-helper epitope and a tumor-associated glycopeptide can elicit in mice exceptionally high titers of IgG antibodies that can recognize cancer cells expressing the tumor-associated carbohydrate. The superior properties of the vaccine candidate are attributed to the local production of cytokines, upregulation of co-stimulatory proteins, enhanced uptake by macrophages and dendritic cells and avoidance of epitope suppression. 相似文献