Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Angew Chem Int Ed Engl ; 63(12): e202315222, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38299697

RESUMO

A new electrochemical transformation is presented that enables chemists to couple simple alkyl carboxylic acid derivatives with an electrophilic amine reagent to construct C(sp3 )-N bond. The success of this reaction hinges on the merging of cooperative electrochemical reduction with nickel catalysis. The chemistry exhibits a high degree of practicality, showcasing its wide applicability with 1°, 2°, 3° carboxylic acids and remarkable compatibility with diverse functional groups, even in the realm of late-stage functionalization. Furthermore, extensive mechanistic studies have unveiled the engagement of alkyl radicals and iminyl radicals; and elucidated the multifaceted roles played by i Pr2 O, Ni catalyst, and electricity.

2.
Kidney Int ; 104(3): 562-576, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37414396

RESUMO

Multiple genome-wide association studies (GWASs) have reproducibly identified the MTMR3/HORMAD2/LIF/OSM locus to be associated with IgA nephropathy (IgAN). However, the causal variant(s), implicated gene(s), and altered mechanisms remain poorly understood. Here, we performed fine-mapping analyses based on GWAS datasets encompassing 2762 IgAN cases and 5803 control individuals, and identified rs4823074 as the candidate causal variant that intersects the MTMR3 promoter in B-lymphoblastoid cells. Mendelian randomization studies suggested the risk allele may modulate disease susceptibility by affecting serum IgA levels through increased MTMR3 expression. Consistently, elevated MTMR3 expression in peripheral blood mononuclear cells was observed in patients with IgAN. Further mechanistic studies in vitro demonstrated that MTMR3 increased IgA production dependent upon its phosphatidylinositol 3-phosphate binding domain. Moreover, our study provided the in vivo functional evidence that Mtmr3-/- mice exhibited defective Toll Like Receptor 9-induced IgA production, glomerular IgA deposition, as well as mesangial cell proliferation. RNA-seq and pathway analyses showed that MTMR3 deficiency resulted in an impaired intestinal immune network for IgA production. Thus, our results support the role of MTMR3 in IgAN pathogenesis by enhancing Toll Like Receptor 9-induced IgA immunity.


Assuntos
Glomerulonefrite por IGA , Animais , Camundongos , Alelos , Estudo de Associação Genômica Ampla , Glomerulonefrite por IGA/patologia , Imunoglobulina A , Leucócitos Mononucleares/metabolismo , Receptor Toll-Like 9 , Humanos
3.
New Phytol ; 232(1): 388-403, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143496

RESUMO

Topological cytonuclear discordance is commonly observed in plant phylogenetic and phylogeographic studies, yet few studies have attempted to detect two other forms of cytonuclear discordance (branch length and geographical) and to uncover the causes of the discordance. We used the whole nuclear and chloroplast genome data from 80 individual Asian butternuts to reveal the pattern and processes of cytonuclear discordance. Our findings indicate that the chloroplast genome had substantially deeper divergence (branch-length discordance) and a steeper cline in the contact zone (geographic discordance) compared with the nuclear genome. After various hypothesis have been tested, the results suggest that incomplete lineage sorting, positive selection and cytonuclear incompatibility are probably insufficient to explain this pattern. However, isolation-by-distance analysis and gene flow estimation point to a much higher level of gene flow by pollen compared with by seeds, which may have slowed down lineage divergence and mediated wider contact for nuclear genome compared with the chloroplast genome. Altogether, this study highlights a critical role of sex-biased dispersal in causing discordance between the nuclear and plastid genome of Asian butternuts. Given its ubiquity among plants, asymmetric gene flow should be given a high priority in future studies of cytonuclear discordance.


Assuntos
Fluxo Gênico , Genoma de Cloroplastos , Núcleo Celular/genética , Filogenia , Pólen/genética , Sementes/genética
4.
Mol Biol Evol ; 36(11): 2451-2461, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31163451

RESUMO

Persian walnut (Juglans regia) is cultivated worldwide for its high-quality wood and nuts, but its origin has remained mysterious because in phylogenies it occupies an unresolved position between American black walnuts and Asian butternuts. Equally unclear is the origin of the only American butternut, J. cinerea. We resequenced the whole genome of 80 individuals from 19 of the 22 species of Juglans and assembled the genome of its relatives Pterocarya stenoptera and Platycarya strobilacea. Using phylogenetic-network analysis of single-copy nuclear genes, genome-wide site pattern probabilities, and Approximate Bayesian Computation, we discovered that J. regia (and its landrace J. sigillata) arose as a hybrid between the American and the Asian lineages and that J. cinerea resulted from massive introgression from an immigrating Asian butternut into the genome of an American black walnut. Approximate Bayesian Computation modeling placed the hybrid origin in the late Pliocene, ∼3.45 My, with both parental lineages since having gone extinct in Europe.

5.
Clin Exp Pharmacol Physiol ; 47(4): 599-608, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31821581

RESUMO

Diabetic nephropathy (DN) is the major microvascular complication of diabetes mellitus and the most important cause of end-stage renal disease worldwide. Metformin is the preferred oral hypoglycaemic drug for type 2 diabetes mellitus (T2DM). Recent studies have shown that besides lowering blood glucose, metformin also has protective effects on renal function, but its mechanism is not clear. In this study, we established a diabetic rat model by high-fat feeding combined with intraperitoneal injection of streptozotocin. Their changes of renal function, oxidative stress, histopathology and structure, and autophagy were observed after 8 weeks of metformin treatment at different dose. Sirt1 inhibitor EX527 and metformin were used to observe whether the protective effect of metformin on DN kidney was achieved through the Sirt1/FoxO1 autophagic signalling pathway. The results showed that metformin could protect renal function by up-regulating autophagy level, alleviating oxidative stress level of renal tissue and pathological and structural changes of glomeruli, and inhibiting the expression of extracellular matrix. Sirt1 inhibitor could block the protective effect of metformin on kidney of diabetic rats, suggesting that metformin could alleviate kidney injury in diabetic rats by inducing Sirt1/FoxO1 autophagy signal axis. So metformin could alleviate renal injury in diabetic rats, which may be achieved by regulating Sirt1/FoxO1 autophagic signalling pathway and inducing renal autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Diabetes Mellitus/patologia , Proteína Forkhead Box O1/metabolismo , Rim/efeitos dos fármacos , Metformina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Animais , Citoproteção/efeitos dos fármacos , Diabetes Mellitus/induzido quimicamente , Diabetes Mellitus/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Ratos
7.
Br J Haematol ; 180(3): 395-411, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29327472

RESUMO

Immune thrombocytopenia (ITP) is an autoimmune disease. Mesenchymal stem cells (MSCs) play important roles in the physiology and homeostasis of the haematopoietic system, including supporting megakaryocytic differentiation from CD34+ haematopoietic progenitor cells. Tumour necrosis factor alpha-induced protein 3 (TNFAIP3, also termed A20) plays a key role in terminating NF-κB signalling. Human genetic studies showed that the polymorphisms of the TNFAIP3 gene may contribute to ITP susceptibility. In this study, we showed a significant decrease in TNFAIP3 and increase in NF-κB/SMAD7 in ITP-MSCs. In co-cultures with CD34+ cells, NF-κB was overexpressed in MSCs from healthy controls (HC-MSCs) after transfection with NFKBIA (IκB)-specific short hairpin (sh)RNAs, resulting in MSC deficiency and a reduction in megakaryocytic differentiation and thrombopoiesis. Knockdown of TNFAIP3 expression using TNFAIP3-specific shRNAs in HC-MSCs affected megakaryocytopoiesis. However, IKBKB knockdown corrected megakaryocytopoiesis inhibition in the ITP-MSCs by decreasing NF-κB expression. Amplified TNFAIP3 expression in ITP-MSCs by TNFAIP3 cDNA can facilitate megakaryocyte differentiation. shRNA-mediated knockdown of SMAD7 expression rescued the impaired MSC function in ITP patients. Therefore, we demonstrate that a pathological reduction in TNFAIP3 levels induced NF-κB/SMAD7 pathway activation, causing a deficiency in MSCs in ITP patients. The ability of ITP-MSCs to support megakaryocytic differentiation and thrombopoiesis of CD34+ cells was impaired.


Assuntos
Células-Tronco Mesenquimais/metabolismo , NF-kappa B/metabolismo , Púrpura Trombocitopênica Idiopática/etiologia , Púrpura Trombocitopênica Idiopática/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Trombopoese , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Biomarcadores , Medula Óssea/patologia , Estudos de Casos e Controles , Diferenciação Celular , Ensaio de Unidades Formadoras de Colônias , Citocinas/biossíntese , Expressão Gênica , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/patologia , Modelos Biológicos , NF-kappa B/genética , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/genética , Trombopoese/efeitos dos fármacos , Trombopoese/genética , Fator de Crescimento Transformador beta/metabolismo , Tretinoína/farmacologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética
8.
Chemistry ; 24(22): 5920-5926, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29424048

RESUMO

The mass-selected Fe2 O+ cation mediated propane oxidation by O2 was investigated by mass spectrometry and density functional theory calculations. In the reaction of Fe2 O+ with C3 H8 , H2 was liberated by C-H bond activation to give Fe2 OC3 H6+ . Interestingly, when a mixture of C3 H8 /O2 was introduced into the reactor, an intense signal that corresponded to the Fe2 O2+ cation was present; the experiments indicated that O2 was activated in its reaction with Fe2 O(C3 H6 )+ to give Fe2 O2+ and C3 H6 O (acetone or propanal). A Langmuir-Hinshelwood-like mechanism was adopted in the propane oxidation reaction by O2 on gas-phase Fe2 O+ cations. In comparison with the absence of Fe2 O2+ in the reaction of Fe2 O+ with O2 , the ligand effect of C3 H6 on Fe2 OC3 H6+ is important in the oxygen activation reaction. The theoretical results are consistent with the experimental observations. The propane oxidation by O2 in the presence of Fe2 O+ might be applied as a model for alkane and O2 activations over iron oxide catalysts, and the mechanisms and kinetic data are useful for understanding corresponding heterogeneous reactions.

9.
Eur J Immunol ; 46(5): 1152-61, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26887860

RESUMO

Follicular helper T (Tfh) cells provide crucial help to germinal center B (GCB) cells for proper antibody production, and a specialized subset of regulatory T cells, follicular regulatory T (Tfr) cells, modulate this process. However, Tfr-cell function in the GC is not well understood. Here, we define Tfr cells as a CD4(+) Foxp3(+) CXCR5(hi) PD-1(hi) CD25(low) TIGIT(high) T-cell population. Furthermore, we have used a novel mouse model ("Bcl6FC") to delete the Bcl6 gene in Foxp3(+) T cells and thus specifically deplete Tfr cells. Following immunization, Bcl6FC mice develop normal Tfh- and GCB-cell populations. However, Bcl6FC mice produce altered antigen-specific antibody responses, with reduced titers of IgG and significantly increased IgA. Bcl6FC mice also developed IgG antibodies with significantly decreased avidity to antigen in an HIV-1 gp120 "prime-boost" vaccine model. In an autoimmune lupus model, we observed strongly elevated anti-DNA IgA titers in Bcl6FC mice. Additionally, Tfh cells from Bcl6FC mice consistently produce higher levels of Interferon-γ, IL-10 and IL-21. Loss of Tfr cells therefore leads to highly abnormal Tfh-cell and GCB-cell responses. Overall, our study has uncovered unique regulatory roles for Tfr cells in the GC response.


Assuntos
Citocinas/biossíntese , Centro Germinativo/imunologia , Imunoglobulina G/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Animais , Afinidade de Anticorpos , Autoimunidade , Citocinas/imunologia , DNA/imunologia , Fatores de Transcrição Forkhead/análise , Anticorpos Anti-HIV/biossíntese , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp120 do Envelope de HIV/metabolismo , Imunoglobulina A/biossíntese , Imunoglobulina A/imunologia , Imunoglobulina G/biossíntese , Interferon gama/imunologia , Interleucina-10/imunologia , Interleucinas/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Camundongos , Proteínas Proto-Oncogênicas c-bcl-6/deficiência , Proteínas Proto-Oncogênicas c-bcl-6/genética , Linfócitos T Reguladores/fisiologia , Vacinação
10.
J Immunol ; 195(5): 2080-9, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26188063

RESUMO

The transcription factor Bcl6 is required for development of follicular helper T (TFH) cells. Cytokines that activate Stat3 promote Bcl6 expression and TFH cell differentiation. Previous studies with an acute virus infection model showed that TFH cell differentiation was decreased but not blocked in the absence of Stat3. In this study, we further analyzed the role of Stat3 in TFH cells. In Peyer's patches, we found that compared with wild-type, Stat3-deficient TFH cells developed at a 25% lower rate and expressed increased IFN-γ and IL-4. Whereas Peyer's patch germinal center B cells developed at normal numbers with Stat3-deficient TFH cells, IgG1 class switching was greatly increased. Following immunization with sheep RBCs, splenic Stat3-deficient TFH cells developed at a slower rate than in control mice, and splenic germinal center B cells were markedly decreased. Stat3-deficient TFH cells developed poorly in a competitive bone marrow chimera environment. Under all conditions tested, Stat3-deficient TFH cells overexpressed both IL-4 and Bcl6, a pattern specific for the TFH cell population. Finally, we found in vitro that repression of IL-4 expression in CD4 T cells by Bcl6 required Stat3 function. Our data indicate that Stat3 can repress the expression of Bcl6 and IL-4 in TFH cells, and that Stat3 regulates the ability of Bcl6 to repress target genes. Overall, we conclude that Stat3 is required to fine-tune the expression of multiple key genes in TFH cells, and that the specific immune environment determines the function of Stat3 in TFH cells.


Assuntos
Proteínas de Ligação a DNA/imunologia , Interleucina-4/imunologia , Fator de Transcrição STAT3/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Eritrócitos/imunologia , Citometria de Fluxo , Expressão Gênica/imunologia , Imunização/métodos , Interleucina-4/genética , Interleucina-4/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina/imunologia , Nódulos Linfáticos Agregados/imunologia , Nódulos Linfáticos Agregados/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Ovinos , Baço/imunologia , Baço/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo
11.
Phys Chem Chem Phys ; 19(4): 3136-3142, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28083590

RESUMO

The reactivity of gas-phase cluster anions Ta3N2- with C2H4 under thermal collision conditions was studied by mass spectrometry in conjunction with density functional theory calculations. The full dehydrogenation of the C2H4 molecule was observed, with the formation of two dihydrogen molecules. Interestingly, the two carbon atoms originating from the first C2H4 molecule are used to construct another cluster Ta3N2C2-, which can activate one more C2H4 releasing one H2 molecule. Therefore, three dihydrogen molecules are liberated from two ethene molecules in the overall reaction. The full dehydrogenation of C2H4 by gas-phase anions as well as the structure and reactivity of M-N-C (M: transition metal) cluster is reported for the first time. The properties of Ta3N2- and Ta3N2C2- elucidated herein are of use in providing fundamental information that is necessary to tailor the design of new and effective catalysts by applying the related materials.

12.
Inflamm Res ; 65(3): 193-202, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26621504

RESUMO

OBJECTIVE: To explore the influence of chemokine, CXCL16, on the expression of the receptor activator nuclear factor κB ligand (RANKL) in rheumatoid arthritis (RA) fibroblast-like synoviocytes (RA-FLS). METHODS: The expression of CXCL16/CXCR6 and RANKL in RA or osteoarthritis (OA) patient synovia was examined by Western blot and immunohistochemistry. The serum concentration of CXCL16 and RANKL was measured by enzyme-linked immunosorbent assay (ELISA). RA-FLS were treated with recombinant CXCL16, and RANKL mRNA and protein were measured using PCR, Western blot and ELISA. RESULTS: The synovial expression of CXCL16, CXCR6, and RANKL was higher in RA patients than in patients with OA. The serum CXCL16 and RANKL levels were higher in RA patients compared with OA patients and healthy controls. CXCL16 correlated with erythrocyte sedimentation rate, C reactive protein, disease activity, serum rheumatoid factor, and RANKL. RA-FLS treated with CXCL16 showed markedly increased expression of RANKL. When STAT3 or p38 activation was blocked by an inhibitor, CXCL16 failed to upregulate RANKL expression. In contrast, inhibiting the Akt or Erk pathway did not achieve the same effect. CONCLUSIONS: CXCL16 upregulates RANKL expression in RA-FLS and these effects are mainly mediated by the JAK2/STAT3 and p38/MAPK signaling pathways.


Assuntos
Artrite Reumatoide/metabolismo , Quimiocinas CXC/metabolismo , Fibroblastos/metabolismo , Janus Quinase 2/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Ligante RANK/metabolismo , Receptores Depuradores/metabolismo , Fator de Transcrição STAT3/metabolismo , Adulto , Idoso , Quimiocina CXCL16 , Quimiocinas CXC/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ligante RANK/sangue , Ligante RANK/genética , Receptores CXCR6 , Receptores de Quimiocinas/metabolismo , Receptores Depuradores/sangue , Receptores Virais/metabolismo , Membrana Sinovial/citologia
13.
J Phys Chem A ; 120(39): 7786-7791, 2016 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-27623162

RESUMO

The reactivity of the triatomic anions HMoN- and ZrNH- toward alkanes was investigated by means of mass spectrometry in conjunction with density functional theory calculations. HMoN- can activate C-H bond of ethane with the liberation of ethene and hydrogen molecules, and the generation of hydrogen molecules is the major reaction channel; however, no C-H bond activation of ethane was observed over ZrNH- ion, and the density functional theory calculations suggest this pathway is hampered by intrinsic energy barrier. In sharp contrast, another triatomic anion HNbN- can bring about methane activation under thermal conditions, as reported previously. A strong dependence of the chemical reactivity of alkane activation on compositions of active orbitals in the above-mentioned systems is discussed. This combined experimental/computational study may provide new insights into the importance of compositions of active orbitals and their essential role in the reactions of related systems with alkanes.

14.
Platelets ; 27(3): 223-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26338255

RESUMO

The role of Helicobacter pylori (H. pylori) infection on thrombocytopenia in chronic hepatitis B (CHB) related compensatory cirrhotic patients is unknown. We conducted an observational study to determine whether H. pylori plays a role in these patients. A total of 255 patients from three centers in China were enrolled in the study. All patients received nucleoside analogs (NA) therapy and were screened for H. pylori infection. Patients were divided into three groups based on their H. pylori infection status and the therapy administered: patients without H. pylori infection who received NA therapy alone (N = 146); patients with H. pylori infection who received NA therapy alone (n = 48); and patients with H. pylori infection who received H. pylori eradication combined with NA therapy (N = 61). We observed that in CHB compensatory cirrhotic patients with H. pylori infection, the platelets count was significantly lower relative to uninfected patients (31 versus 60 × 10(9)/L, p < 0.01). During a 2-year follow-up, the elevation in platelet count was significantly higher in HBV/H. pylori co-infected patients who received the NA and H. pylori eradication treatment compared to the other two groups (p < 0.01). It suggested that H. pylori infection and eradication treatment combined with NA were independent risk factors associated with platelets response during treatment of thrombocytopenia in CHB compensatory cirrhosis (p < 0.01). In conclusion, H. pylori infection may associate with thrombocytopenia in CHB compensatory cirrhosis. H. pylori eradication combined with NA treatment may prove to be beneficial to CHB compensatory cirrhotic patients with thrombocytopenia who are infected with H. pylori.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori , Hepatite B Crônica/complicações , Cirrose Hepática/complicações , Cirrose Hepática/etiologia , Trombocitopenia/diagnóstico , Trombocitopenia/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Feminino , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Fatores de Risco , Índice de Gravidade de Doença , Trombocitopenia/terapia , Resultado do Tratamento , Adulto Jovem
15.
Angew Chem Int Ed Engl ; 55(16): 4947-51, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-26954294

RESUMO

Investigations of the intrinsic properties of gas-phase transition metal nitride (TMN) ions represent one approach to gain a fundamental understanding of the active sites of TMN catalysts, the activities and electronic structures of which are known to be comparable to those of noble metal catalysts. Herein, we investigate the structures and reactivities of the triatomic anions HNbN(-) by means of mass spectrometry and photoelectron imaging spectroscopy, in conjunction with density functional theory calculations. The HNbN(-) anions are capable of activating CH4 and C2H6 through oxidative addition, exhibiting similar reactivities to free Pt atoms. The similar electronic structures of HNbN(-) and Pt, especially the active orbitals, are responsible for this resemblance. Compared to the inert NbN(-), the coordination of the H atom in HNbN(-) is indispensable. New insights into how to replace noble metals with TMNs may be derived from this combined experimental/computational study.

16.
Reproduction ; 149(2): 163-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25385720

RESUMO

Tri-ortho-cresyl phosphate (TOCP) has been widely used as plasticizers, plastic softeners, and flame retardants in industry and reported to have a deleterious effect on the male reproductive system in animals besides delayed neurotoxicity. Our preliminary results found that TOCP could disrupt the seminiferous epithelium in the testis and inhibit spermatogenesis, but the precise mechanism is yet to be elucidated. This study shows that TOCP inhibited viability of rat spermatogonial stem cells in a dose-dependent manner. TOCP could not lead to cell cycle arrest in the cells; the mRNA levels of p21, p27, p53, and cyclin D1 in the cells were also not affected by TOCP. Meanwhile, TOCP did not induce apoptosis of rat spermatogonial stem cells. After treatment with TOCP, however, both LC3-II and the ratio of LC3-II/LC3-I were markedly increased; autophagy proteins ATG5 and beclin 1 were also increased after treatment with TOCP, indicating that TOCP could induce autophagy in the cells. Ultrastructural observation under the transmission electron microscopy indicated that autophagic vesicles in the cytoplasm containing extensively degraded organelles such as mitochondria and endoplasmic reticulum increased significantly after the cells were treated with TOCP. In summary, we have shown that TOCP can inhibit viability of rat spermatogonial stem cells and induce autophagy of the cells, without affecting cell cycle and apoptosis.


Assuntos
Autofagia/efeitos dos fármacos , Espermatogônias/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Tritolil Fosfatos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/análise , Proteína 5 Relacionada à Autofagia , Proteína Beclina-1 , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Microscopia Eletrônica de Transmissão , Proteínas/análise , Ratos , Espermatogônias/química , Espermatogônias/ultraestrutura , Células-Tronco/química , Células-Tronco/ultraestrutura
17.
J Gen Virol ; 95(Pt 4): 806-815, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24362961

RESUMO

A full-length genome infectious clone is a powerful tool for functional assays in virology. In this study, using a chemical synthesized complete genome of Japanese encephalitis virus (JEV) strain SA14 (GenBank accession no. U14163), we constructed a full-length genomic cDNA clone of JEV. The recovered virus from the cDNA clone replicated poorly in baby hamster kidney (BHK-21) cells and in suckling mice brain. Following serial passage in BHK-21 cells, adaptive mutations within the NS2B and NS4A proteins were recovered in the passaged viruses leading to viruses with a large-plaque phenotype. Mutagenesis analysis, using a genome-length RNA and a replicon of JEV, demonstrated that the adaptive mutations restored replication to different degrees, and the restoration efficiencies were in the order: NS2B-T102M

Assuntos
Adaptação Biológica , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Mutação de Sentido Incorreto , Inoculações Seriadas , Proteínas não Estruturais Virais/genética , Replicação Viral , Animais , Encéfalo/virologia , Linhagem Celular , Cricetinae , Análise Mutacional de DNA , Modelos Animais de Doenças , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/patologia , Encefalite Japonesa/virologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Genética Reversa , Proteínas não Estruturais Virais/metabolismo , Virulência
18.
Kidney Dis (Basel) ; 10(3): 167-180, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38835407

RESUMO

Introduction: IgA nephropathy (IgAN) is a leading cause of end-stage renal disease. The exact pathogenesis of IgAN is not well defined, but some genetic studies have led to a novel discovery that the (immuno)proteasome probably plays an important role in IgAN. Methods: We firstly analyzed the association of variants in the UBE2L3 region with susceptibility to IgAN in 3,495 patients and 9,101 controls, and then analyzed the association between lead variant and clinical phenotypes in 1,803 patients with regular follow-up data. The blood mRNA levels of members of the ubiquitin-proteasome system including UBE2L3 were analyzed in peripheral blood mononuclear cells from 53 patients and 28 healthy controls. The associations between UBE2L3 and the expression levels of genes involved in Gd-IgA1 production were also explored. Results: The rs131654 showed the most significant association signal in UBE2L3 region (OR: 1.10, 95% CI: 1.04-1.16, p = 2.29 × 10-3), whose genotypes were also associated with the levels of Gd-IgA1 (p = 0.04). The rs131654 was observed to exert cis-eQTL effects on UBE2L3 in various tissues and cell types, particularly in immune cell types in multiple databases. The UBE2L3, LUBAC, and proteasome subunits were highly expressed in patients compared with healthy controls. High expression levels of UBE2L3 were not only associated with higher proteinuria (r = 0.34, p = 0.01) and lower eGFR (r = -0.28, p = 0.04), but also positively correlated with the gene expression of LUBAC and other proteasome subunits. Additionally, mRNA expression levels of UBE2L3 were also positively correlated with IL-6 and RELA, but negatively correlated with the expression levels of the key enzyme in the process of glycosylation including C1GALT1 and C1GALT1C1. Conclusion: In conclusion, by combined genetic association and differed expression analysis of UBE2L3, our data support a role of genetically conferred dysregulation of the (immuno)proteasome in regulating galactose-deficient IgA1 in the development of IgAN.

19.
Adv Mater ; : e2401918, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662940

RESUMO

The complex pathologies in Alzheimer's disease (AD) severely limit the effectiveness of single-target pharmic interventions, thus necessitating multi-pronged therapeutic strategies. While flexibility is essentially demanded in constructing such multi-target systems, for achieving optimal synergies and also accommodating the inherent heterogeneity within AD. Utilizing the dynamic reversibility of supramolecular strategy for conferring sufficient tunability in component substitution and proportion adjustment, amphiphilic calixarenes are poised to be a privileged molecular tool for facilely achieving function integration. Herein, taking ß-amyloid (Aß) fibrillation and oxidative stress as model combination pattern, a supramolecular multifunctional integration is proposed by co-assembling guanidinium-modified calixarene with ascorbyl palmitate and loading dipotassium phytate within calixarene cavity. Serial pivotal events can be simultaneously addressed by this versatile system, including 1) inhibition of Aß production and aggregation, 2) disintegration of Aß fibrils, 3) acceleration of Aß metabolic clearance, and 4) regulation of oxidative stress, which is verified to significantly ameliorate the cognitive impairment of 5×FAD mice, with reduced Aß plaque content, neuroinflammation, and neuronal apoptosis. Confronted with the extremely intricate clinical realities of AD, the strategy presented here exhibits ample adaptability for necessary alterations on combinations, thereby may immensely expedite the advancement of AD combinational therapy through providing an exceptionally convenient platform.

20.
Kidney Int Rep ; 9(4): 1057-1066, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38765575

RESUMO

Introduction: Immunoglobulin A nephropathy (IgAN) has been reported to coexist with hepatitis B virus (HBV) infection. Despite the clinical significance of this association, there is a lack of comprehensive research investigating the impact of various common conditions following HBV infection and the potential influence of anti-HBV therapy on the progression of IgAN. Methods: We investigated 3 distinct states of HBV infection, including chronic HBV infection, resolved HBV infection, and the deposition of hepatitis B antigens in renal tissue, in a follow-up database of 1961 patients with IgAN. IgAN progression was defined as a loss of estimated glomerular filtration rate (eGFR) >40%. Multivariable cause-specific hazards models to analyze the relationship between HBV states and IgAN progression. Results: Chronic HBV infection was identified as an independent risk factor for IgAN progression, supported by both prematching analysis (hazard ratio [HR], 1.61; 95% confidence interval [CI], 1.06-2.44; P = 0.024) and propensity-score matching analysis (HR, 1.74; 95% CI 1.28-2.37; P < 0.001). Conversely, resolved HBV infection showed no significant association with IgAN progression (HR, 1.01; 95% CI 0.67-1.52; P = 0.969). Moreover, the presence of HBV deposition in the kidneys and the utilization of anti-HBV therapy did not appear to be significant risk factors for renal outcomes (P > 0.05). Conclusion: Chronic HBV infection is an independent risk factor for IgAN progression, whereas resolved HBV infection is not. In patients with IgAN, management of concurrent chronic HBV infection should be enhanced. The presence of HBV deposition in the kidneys and the use of anti-HBV medications do not impact the kidney disease progression in patients with IgAN with concurrent HBV infection.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA