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91.
ObjectivesZinc, which is found in high concentrations in the β-cells of the pancreas, is also a critical component for the endocrine functions of the pancreas. SLC30A8/ZnT8 is the carrier protein responsible for the transport of zinc from the cytoplasm to the insulin granules. The aim of this study was to investigate how dietary zinc status affects pancreatic beta cell activation and ZnT8 levels in infant male rats born to zinc-deficient mothers.MethodsThe study was performed on male pups born to mothers fed a zinc-deficient diet. A total of 40 male rats were divided into 4 equal groups. Group 1: In addition to maternal zinc deficiency, this group was fed a zinc-deficient diet. Group 2: In addition to maternal zinc deficiency, this group was fed a standard diet. Group 3: In addition to maternal zinc deficiency, this group was fed a standard diet and received additional zinc supplementation. Group 4: Control group. Pancreas ZnT8 levels were determined by ELISA method and insulin-positive cell ratios in β-cells by immunohistochemistry.ResultsThe highest pancreatic ZnT8 levels and anti-insulin positive cell ratios in the current study were obtained in Group 3 and Group 4. In our study, the lowest pancreatic ZnT8 levels were obtained in Group 1 and Group 2, and the lowest pancreatic anti-insulin positive cell ratios were obtained in Group 1.ConclusionThe results of the present study; in rats fed a zinc-deficient diet after maternal zinc deficiency has been established shows that ZnT8 levels and anti-insulin positive cell ratios in pancreatic tissue, which is significantly suppressed, reach control values with intraperitoneal zinc supplementation.  相似文献   
92.
Embryonic external genitalia (genital tubercle [GT]) protrude from the cloaca and outgrow as cloacal development progresses. Individual gene functions and knockout phenotypes in GT development have been extensively analyzed; however, the interactions between these genes are not fully understood. In this study, we investigated the role of p63, focusing on its interaction with the Shh–Wnt/Ctnnb1–Fgf8 pathway, a signaling network that is known to play a role in GT outgrowth. p63 was expressed in the epithelial tissues of the GT at E11.5, and the distal tip of the GT predominantly expressed the ΔNp63α isoform. The GTs in p63 knockout embryos had normal Shh expression, but CTNNB1 protein and Fgf8 gene expression in the distal urethral epithelium was decreased or lost. Constitutive expression of CTNNB1 in p63-null embryos restored Fgf8 expression, accompanied by small bud structure development; however, such bud structures could not be maintained by E13.5, at which point mutant GTs exhibited severe abnormalities showing a split shape with a hemorrhagic cloaca. Therefore, p63 is a key component of the signaling pathway that triggers Fgf8 expression in the distal urethral epithelium and contributes to GT outgrowth by ensuring the structural integrity of the cloacal epithelia. Altogether, we propose that p63 plays an essential role in the signaling network for the development of external genitalia.  相似文献   
93.
A study is presented of the conformational characteristics of NMR-derived protein structures in the Protein Data Bank compared to X-ray structures. Both ensemble and energy-minimized average structures are analyzed. We have addressed the problem using the methods developed for crystal structures by examining the distribution of ?, Ψ, and χ angles as indicators of global conformational irregularity. All these features in NMR structures occur to varying degrees in multiple conformational states. Some measures of local geometry are very tightly constrained by the methods used to generate the structure, e.g., proline ? angles, α-helix ?, Ψ angles, ω angles, and Cα chirality. The more lightly restrained torsion angles do show increasead clustering as the number of overall experimental observations increases. ?, Ψ, and χ1 angle conformational heterogeneity is strongly correlated with accessibility but shows additional differences which reflect the differing number of observations possible in NMR for the various side chains (e.g., many for Trp, few for Ser). In general, we find that the core is defined to a notional resolution of 2.0 to 2.3 Å. Of real interest is the behavior of surface residues and in particular the side chains where multiple rotameric states in different structures can vary from 10% to 88%. Later generation structures show a much tighter definition which correlates with increasing use of J-coupling information, stereospecific assignments, and heteronumclear techniques. A suite of programs is being developed to address the special needs of NMR-derived structures which will take into account the existence of increased mobility in solution. © 1993 Wiley-Liss, Inc.  相似文献   
94.
Thirty-five ketone-isobenzofuranone hybrids ( 1 – 35 ) were designed, synthesized, and evaluated for their herbicidal activity against Chinese amaranth (Amaranthus tricolor) and barnyard grass (Echinochloa crus-galli). The structure-activity relationship (SAR) results revealed that the position and type of substituent were crucial for activity. The o-substituted derivatives outperformed the m- and p-substituted derivatives. Compounds with strong electron-donating groups (OH, OMe) had low activity, while those with heterocycles (N-methylpyrrole, furan, and thiophene) had a moderate herbicidal effect. Compounds with a weak electron-donating group (Me) and weak, moderate, and strong electron-withdrawing groups (F, Cl, Br, and NO2) showed promising herbicidal activity. Among these, the o-F substituted compound ( 20 ) was the most effective against Chinese amaranth, and the o-Cl substituted compound ( 23 ) was the most potent against barnyard grass. This is the first time the herbicidal potential of ketone-isobenzofuranone hybrids has been studied. The discovery of current chemical clues would be beneficial for the development of novel herbicides.  相似文献   
95.
Autophagy plays an important role in tissue remodeling during insect development. The interplay between autophagy-related (ATG) proteins and caspases regulates the autophagic activity of ATGs, thereby modulating the process of autophagy. Our previous study characterized BmCaspase-8-like (BmCasp8L) as a caspase suppressor that inhibits apoptosis and immune signaling by suppressing the activation of death-related ced-3/Nedd2-like caspase (DREDD), a caspase-8 homolog in silkworm. In this study, we explored the regulatory role of BmCasp8L in autophagy. We found that the expression of Bmcasp8l increased from the late spinning stage to the pupa stage in the posterior silk gland (PSG), correlating with the expression patterns of Bmatg8 and Bmatg6. RNA interference-mediated downregulation of BmCasp8L expression significantly decreased starvation-induced autophagic influx as determined by the levels of BmATG8–phosphatidylethanolamine and the percentage of cells displaying punctate enhanced green fluorescent protein-BmATG8. Conversely, the overexpression of BmCasp8L significantly increased autophagic influx. We also found that BmCasp8L underwent autophagic degradation induced by starvation and that it was colocalized with BmATG8. Lastly, we demonstrated that BmDREDD attenuated autophagy and BmCasp8L suppressed BmDREDD-mediated cleavage of BmATG6. Taken together, our results demonstrated that BmCasp8L is a novel proautophagic molecule which suppresses BmDREDD-mediated cleavage of BmATG6 and is a target for autophagy.  相似文献   
96.
摘要 目的:探讨传染性单核细胞增多症(IM)患儿外周血中性粒细胞/淋巴细胞比值(NLR)、CD4+/CD8+比值、腺苷脱氨酶(ADA)与EB病毒(EBV)-脱氧核糖核酸(DNA)载量的相关性,分析其对IM患儿肝损害的影响。方法:选择2019年1月至2022年4月我院儿科收治的102例IM患儿(IM组),另选择同期我科收治的95例EB病毒检测阴性的发热患儿(非IM组)和体检健康的73例健康儿童(对照组)。根据是否发生肝损害将IM患儿分为肝损害组(61例)和非肝损害组(41例)。比较外周血NLR、CD4+/CD8+比值、ADA与EBV-DNA载量,Pearson法分析NLR、CD4+/CD8+比值、ADA与EBV-DNA载量的相关性。多因素Logistic回归分析IM患儿发生肝损害的影响因素。结果:IM组ADA高于非IM组和对照组(P<0.05),且非IM组高于对照组(P<0.05),NLR、CD4+/CD8+比值低于非IM组和对照组(P<0.05),且非IM组低于对照组(P<0.05),IM组EBV-DNA载量高于非IM组(P<0.05)。IM患儿ADA与EBV-DNA载量呈正相关(r=0.493,P<0.05),NLR、CD4+/CD8+比值与EBV-DNA载量呈负相关(r=-0.419、-472,P<0.05)。肝损害组ADA、EBV-DNA载量高于非肝损害组(P<0.05),NLR、CD4+/CD8++比值低于非肝损害组(P<0.05)。肝脏肿大、高EBV-DNA载量、高ADA是IM患儿肝损害的危险因素(P<0.05),高NLR、高CD4+/ CD8+比值是保护因素(P<0.05)。结论:IM患儿ADA增高,NLR、CD4+/CD8+比值降低,与EBV-DNA载量增加以及肝损害有关。  相似文献   
97.
Summary A new application of the HMBC experiment is presented that provides a useful means to discriminate between H2 and H8 proton resonances, to assign the base proton resonances to the various residue types and, most importantly, to correlate the H2 and H8 protons for adenine or inosine residues in natural abundance 13C fragments. The utility of this experiment is demonstrated for an unlabeled DNA 20-mer. Thanks to the obtained results, preliminary conclusions could be drawn regarding the molecular conformations of the non-canonical G/I-A base pairs in the hairpin formed by this fragment.  相似文献   
98.
The anti- and pro-oxidative effects of phenolic compounds and antioxidants were studied in two different in vitro model systems utilizing ethyl linoleate and 2′-deoxyguanosine (2′-dG) as oxidative substrates, and a Fenton reaction (H2O2, Fe2+) to initiate oxidation. Oxidation of the biomolecules in both model systems exhibited dose dependency. In the 2′-dG assay, oxidation was closely related to H2O2 generation, which occurred during autoxidation of the phenolics. Hydroxylating activity was greatly enhanced by Mn2+ and Cu2+, but not by Zn2+ or Co2+. Ethyl linoleate peroxidation was inhibited by low concentrations of catechol, quercitin, and instant coffee. However, peroxidation was promoted by high concentrations of the same compounds, probably by recycling of chelated inactive Fe3+ to the active Fe2+ state.  相似文献   
99.
Feeding of a whole casein diet, which abolished the αs1-casein-specific proliferation and IFN-γ productivity of CD4+ T cells, did not affect the proliferative response of CD8+ T cells with regard to the antigen dose response, cell dose response, kinetics of the proliferation and epitope specificity, as well as IFN-γ production. To assess the characteristics of the CD8+ T cells, we established αs1-casein-specific CD8+ T cell clones from both casein-fed and control mice. The established clones produced different amount of IFN-γ and IL-10, and one clone derived from the casein-fed mice produced a remarkable amount of IL-10. The clones from casein-fed mice produced considerable amounts of TGF-β, while those from control mice produced only small amounts. The possible role of CD8+ T cells in oral tolerance is discussed. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
100.
Analysis of clonality in cytologic material using the polymerase chain reaction (PCR) Immunoglobulin heavy chain (IgH) gene rearrangement analysis was performed on 27 fine needle aspiration (FNA) specimens (13 reactive hyperplasia, 11 B cell non-Hodgkin's lymphoma (B-NHL), one Hodgkin's disease and two suspicious of non-Hodgkin's lymphoma). Satisfactory amplification was achieved in 23/27 cases. A polyclonal pattern was seen in 14 cases (11 reactive hyperplasia, one B-NHL, one suspicious of lymphoma, one Hodgkin's disease). A monoclonal band was seen in nine cases (eight B-NHL, one reactive hyperplasia). Amplification was unsuccessful in four cases. Clonal analysis by PCR-based IgH gene rearrangement analysis can be successfully applied to FNA material and can be useful in diagnosis, but the results must be interpreted in conjunction with morphology and other ancillary information. Analyse de la clonalité en utilisant la PCR sur matériel cytologique L'analyse des réarrangements géniques des chaînes lourdes des immunoglobulines (IgH) a été réalisée sur 27 produits de ponction à l'aiguille fine (13 cas d'hyperplasie réactionnelle, 11 cas de lymphome non hodgkinien de type B (LNH-B), un cas de maladie de Hodgkin et deux cas suspects de lymphome malin non hodgkinien. Une amplification satisfaisante a été obtenue dans 23 cas sur 27. Un aspect polychonal a été observé dans 14 cas (11 hyperplasies réactionnelles, 1 lymphome malin non hodgkinien de type B, 1 cas suspect de lymphome, 1 cas de maladie de Hodgkin). Une bande monoclonale a été observée dans 9 cas (8 LNH-B, 1 hyperplasie réactionnelle). L'amplification n'a pas réussi dans quatre cas. L'analyse de la clonalité par analyse des réarrangements géniques par PCR peut être appliquée avec succès au matériel cytologique qui est obtenu par ponction à l'aiguille fine et elle peut être utile au plan diagnostique, mais les résultats doivent étre interprétés en intégrant les informations morphologiques et les autres données complémentaires. Polymerase Chain Reaction an zytologischem Material Die Analyse schwerer Immunglobulinketten (IgH) wurde an 27 FNP (13 reaktive Hyperplasien, 11 B-NHL, 1 Hodgkin und und zwie verdächtige Fälle) analysiert. Eine ausreichende Amplifikation wurde in 23/27 Fällen erzielt. Ein polyklonales Muster wurde in 14 Fällen beobachtet (11 reaktive Hyperplasien, 1 B-NHL, 1 Hodgkin sowie 1 verdächtiger Fall). Ein monoklonales Band wurde 9 mal gefunden (8 B-NHL, 1 reaktive Hyperplasie). Die Amplifikation war ungenügend in 4 Fällen. Die PCR-Analyse kann für die Diagnostik von Nutzen sein muss jedoch zusammen mit der Morphologie und anderen Informationen interpretiert werden.  相似文献   
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