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1.
Synthesis of a library of novel trans 6-methoxy-1,1-dimethyl-2-phenyl-3-aryl-2,3-dihydro-1H-inden-4-yloxy alkyl amines and their antimycobacterial activity against drug sensitive and multidrug resistant strains of Mycobacterium tuberculosis have been reported. All the new compounds in the series exhibited MIC between 1.56 and 6.25 μg/ml. Two compounds 1i and 1j with low MIC and low cytotoxicity showed significant reduction in CFU in infected mouse macrophages at 1× MIC concentration. The compound 1i inhibited the growth of M. tuberculosis in mice at 100 mg/kg dose with 1.35 log10 reduction of CFU in lungs tissue and was active against non-replicating Mycobacterium tuberculosis under anaerobic condition.  相似文献   
2.
Kainate receptors (KARs) are a class of ionotropic glutamate receptors that are expressed throughout the central nervous system. The function and subcellular localization of KARs are tightly regulated by accessory proteins. We have previously identified the single-pass transmembrane proteins, Neto1 and Neto2, to be associated with native KARs. In the hippocampus, Neto1, but not Neto2, controls the abundance and modulates the kinetics of postsynaptic KARs. Here we evaluated whether Neto2 regulates synaptic KAR levels in the cerebellum where Neto1 expression is limited to the deep cerebellar nuclei. In the cerebellum, where Neto2 is present abundantly, we found a ∼40% decrease in GluK2-KARs at the postsynaptic density (PSD) of Neto2-null mice. No change, however, was observed in total level of GluK2-KARs, thereby suggesting a critical role of Neto2 on the synaptic localization of cerebellar KARs. The presence of a putative class II PDZ binding motif on Neto2 led us to also investigate whether it interacts with PDZ domain-containing proteins previously implicated in regulating synaptic abundance of KARs. We identified a PDZ-dependent interaction between Neto2 and the scaffolding protein GRIP. Furthermore, coexpression of Neto2 significantly increased the amount of GRIP associated with GluK2, suggesting that Neto2 may promote and/or stabilize GluK2:GRIP interactions. Our results demonstrate that Neto2, like Neto1, is an important auxiliary protein for modulating the synaptic levels of KARs. Moreover, we propose that the interactions of Neto1/2 with various scaffolding proteins is a critical mechanism by which KARs are stabilized at diverse synapses.  相似文献   
3.
Stable transfectants of Chinese hamster ovary (CHO) cells were developed that expressed the protein encoded by a human insulin-like growth factor I (IGF-I) receptor cDNA. The transfected cells expressed approximately 25,000 high affinity receptors for IGF-I (apparent Kd of 1.5 X 10(-9) M), whereas the parental CHO cells expressed only 5,000 receptors per cell (apparent Kd of 1.3 X 10(-9) M). A monoclonal antibody specific for the human IGF-I receptor inhibited IGF-I binding to the expressed receptor and immunoprecipitated polypeptides of apparent Mr values approximately 135,000 and 95,000 from metabolically labeled lysates of the transfected cells but not control cells. The expressed receptor was also capable of binding IGF-II with high affinity (Kd approximately 3 nM) and weakly recognized insulin (with about 1% the potency of IGF-I). The human IGF-I receptor expressed in these cells was capable of IGF-I-stimulated autophosphorylation and phosphorylation of endogenous substrates in the intact cell. This receptor also mediated IGF-I-stimulated glucose uptake, glycogen synthesis, and DNA synthesis. The extent of these responses was comparable to the stimulation by insulin of the same biological responses in CHO cells expressing the human insulin receptor. These results indicate that the isolated cDNA encodes a functional IGF-I receptor and that there are no inherent differences in the abilities of the insulin and IGF-I receptors to mediate rapid and long term biological responses when expressed in the same cell type. The high affinity of this receptor for IGF-II also suggests that it may be important in mediating biological responses to IGF-II as well as IGF-I.  相似文献   
4.
Developing wheat (Triticum aestivum L.) endosperm was examined using ultrathin sections prepared from tissues harvested at 5, 9, 16 and 25 d after flowering. Protein bodies were evident by 9 d and displayed a variety of membranous structures and inclusions. The Golgi apparatus was a prominent organelle at all stages, and by 9 d was associated with small electron-dense inclusions. By immunocytochemical techniques, gliadin (wheat prolamine) was localized within these vesicles and in homogeneous regions of protein bodies, but not in the lumen of the rough endoplasmic reticulum. The protein bodies appear to enlarge by fusion of smaller protein bodies resulting in larger, irregular-shaped organelles. The affinity of the Golgi-derived vesicles for gliadin-specific probes during the period of maximal storage-protein synthesis and deposition indicates that this organelle includes the bulk, if not all, of the gliadin produced. The involvement of the Golgi apparatus in the packaging of gliadins into protein bodies indicates a pathway which differs from the mode of prolamine deposition in other cereals such as maize, rice and sorghum, and resembles the mechanism employed for the storage of rice glutelin and legume globulins.Abbreviations ER endoplasmic reticulum - IgG immunoglobulin G - DAF days after flowering  相似文献   
5.
An extracellular chitosanase produced by Rhodotorula gracilis CFR-1 that catalyses a limited degradation of chitosan with no detectable generation of glucosamine or reducing groups was identified. Ultracentrifugation, polyacrylamide gel electrophoresis and gel permeation studies suggest that chitosan of average molecular mass 36000 Da was reduced by the enzymic catalysis to nearly one-fourth this size without further hydrolysis of the products. The enzyme, produced constitutively by this yeast, was partially purified and some of its properties were studied.  相似文献   
6.
In the investigation of the intracellular sites of insulin degradation, it might be important whether receptor-bound insulin could be a substrate for insulin-degrading enzyme (IDE). Insulin receptor and IDE were purified from rat liver using a wheat germ agglutinin column and monoclonal anti-IDE antibody affinity column, respectively. [125I]insulin-receptor complex was incubated with various amounts of IDE at 0 degree C in the presence of disuccinimidyl suberate and analyzed by reduced 7.5% SDS-PAGE and autoradiography. With increasing amounts of IDE, the radioactivity of 135 kd band (insulin receptor alpha-subunit) decreased, whereas that of 110 kd band (IDE) appeared then gradually increased, suggesting that IDE could bind to receptor-bound insulin. During incubation of insulin-receptor complex with IDE at 37 degrees C, about half of the [125I]insulin was dissociated from the complex. However, the time course of [125I]insulin degradation in this incubation was essentially identical to that of free [125I]insulin degradation. Cross-linked, non-dissociable receptor-bound [125I]insulin was also degraded by IDE. Rebinding studies to IM-9 cells showed that the receptor binding activity of dissociated [125I]insulin from insulin-receptor complex incubated with IDE was significantly (p less than 0.001) decreased as compared with that without the enzyme. These results, therefore, show that IDE could recognize and degrade receptor-bound insulin, and suggest that IDE may be involved in insulin metabolism during receptor-mediated endocytosis through the degradation of receptor-bound insulin in early neutral vesicles before their internal pH is acidified.  相似文献   
7.
The administration of diazepam 1.0 mg/kg decreased the level of plasma corticosterone in female but not in male Wistar rats. Picrotoxin, another drug affecting GABAergic transmission, also brought about an increase of plasma corticosterone in both sexes. However, in order to achieve a plasma corticosterone increase of similar magnitude (more than 500%) a threefold higher dose of picrotoxin had to be given to males. When the convulsive properties of picrotoxin were tested, it became evident that the dose of picrotoxin (2.5 mg/kg) which was subconvulsive in male was almost 100% convulsive in female rats. The existing sex differences in the response of rats to drugs affecting GABAergic transmission might have possible implications in the treatment of GABA system dysfunction.  相似文献   
8.
Systematic significance of mature embryo of bamboos   总被引:1,自引:0,他引:1  
The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.  相似文献   
9.
The growth curve, nucleic acid and protein content of the various life stages of Aedes aegypti were studied. The larvae of this mosquito were treated with sterilizing doses of the chemosterilants apholate and hempa, and their effects on the above parameters were also investigated. The body-weight increased gradually in the earlier instars and showed a sharp rise from late-fourth instar to the pupa. Adults weighed less than the pupae. Females weighed more than the males. In the controls, DNA and RNA content generally followed the growth curve. RNA content was more than DNA up to the late-fourth instar and the ratio reversed in the later stages. Protein content also followed the growth curve except in adult female, where it was more than in the pupa. In general the treatment with the chemosterilants, apholate and hempa did not seem to alter RNA, DNA and protein content in the whole insect.
Zusammenfassung Wachstumskurve, Nukleinsäure- und Eiweißgehalt verschiedener Entwicklungsstadien der Gelbfieber-Mücke, Aedes aegypti, wurden untersucht. Die Larven dieser Mücke wurden mit sterilisierenden Dosen der Chemosterilantia Apholate und Hempa behandelt und ihre Wirkungen auf die genannten Parameter geprüft. Das Körpergewicht nahm in den frühen Stadien allmählich zu und zeigte vom Ende des 4. Stadiums bis zur Puppe einen steilen Anstieg. Adulte wogen weniger als die Puppen, Weibchen mehr als Männchen. In den Kontrollen folgte der DNS- und RNS-Gehalt im allgemeinen der Wachstumskurve. Der RNS-Gehalt war bis zum späten 4. Stadium größer als der DNS-Gehalt, in den späteren Stadien kehrte sich das Verhältnis um. Der Eiweißgehalt folgte ebenfalls der Wachstumskurve mit Ausnahme bei den Weibchen, wo er höher war als in der Puppe. Im allgemeinen schien die Behandlung mit den Chemosterilantien Apholate und Hempa den RNS-, DNS- und Eiweißgehalt im ganzen Insekt nicht zu verändern.
  相似文献   
10.
Molecular variants of human T-cell lymphotropic virus type I (HTLV-I) have been isolated recently from lifelong residents of remote Melanesian populations, including a Solomon Islander with tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) or HTLV-I myeloneuropathy. To clarify the genetic heterogeneity and molecular epidemiology of disease-associated strains of HTLV-I, we enzymatically amplified, then directly sequenced representative regions of thegag, pol, env, andpX genes of HTLV-I strains from Melanesians with and without TSP/HAM, and aligned and compared these sequences with those of HTLV-I strains from patients with TSP/HAM or adult T-cell leukemia/lymphoma and from asymptomatic carriers from widely separated and culturally disparate populations. Overall, the HTLV-I variant from the Solomon Islander with TSP/HAM, like HTLV-I strains from asymptomatically infected Melanesians, diverged by approx 7% from cosmopolitan HTLV-I strain. No disease-specific viral sequences were found. Gene phylogenies, as determined by the unweighted pair-goup method of assortment and by the maximum parsimony method, indicated that the Melanesian and cosmopolitan strains of HTLV-I have evolved along separate geographically dependent lineages, one comprised of HTLV-I strains from Papua New Guinea and the Solomon Islands, and the other composed of virus strains from Japan, India, the Caribbean, Polynesia, the Americas, and Africa. The total absence of nonhuman primates in Papua New Guinea and the Solomon Islands precludes any possibility that the Melanesian HTLV-I strains have evolved recently from the simian homolog of HTLV-I.  相似文献   
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