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1.
J Transl Med ; 21(1): 327, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198647

RESUMO

The pathogenesis of osteoporosis involves multiple factors, among which alterations in the bone microenvironment play a crucial role in disrupting normal bone metabolic balance. Transient receptor potential vanilloid 5 (TRPV5), a member of the TRPV family, is an essential determinant of the bone microenvironment, acting at multiple levels to influence its properties. TRPV5 exerts a pivotal influence on bone through the regulation of calcium reabsorption and transportation while also responding to steroid hormones and agonists. Although the metabolic consequences of osteoporosis, such as loss of bone calcium, reduced mineralization capacity, and active osteoclasts, have received significant attention, this review focuses on the changes in the osteoporotic microenvironment and the specific effects of TRPV5 at various levels.


Assuntos
Antineoplásicos , Osteoporose , Humanos , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Osteoporose/metabolismo , Osteoclastos , Osso e Ossos/metabolismo , Antineoplásicos/farmacologia , Canais de Cátion TRPV
2.
Opt Express ; 30(15): 27472-27481, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236918

RESUMO

Dual-wavelength switchable emission has been demonstrated in InGaN quantum dot (QD) micro-cavity light-emitting diodes (MCLEDs). By simply modulating the injected current levels, the output of the device can be dynamically tuned between the two distinct cavity modes at 498.5 and 541.7 nm, exhibiting deterministic mode switching in the green spectral range. Owing to the microcavity effect, high spectral purity with a narrow linewidth of 0.21 nm was obtained. According to the experimental and theoretical results, it can be concluded that the dual-wavelength switching for the investigated MCLEDs is ascribed to the broad and tunable gain of a thin InGaN QD active region, together with the mode selection and enhancement effect of the cavity. To provide additional guidelines for controllable dual-wavelength switchable operation in nitride-based light-emitting devices, detailed design and fabrication strategies are discussed. This work presents an effective method to achieve mode switching for practical applications such as multi-wavelength optical recording, frequency mixing, flip-flop and optical switches.

3.
Chemistry ; 28(2): e202103268, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34791731

RESUMO

In this work, by using two kinds of viologen ligands three POM-based Compounds were obtained under hydrothermal conditions, namely [AgI (bmypd)0.5 (ß-Mo8 O26 )0.5 ] (1) (bmypd ⋅ 2Cl=1,1'-[Biphenyl-4,4'-bis(methylene)]bis(4,4'-bipyridyinium)dichloride), [AgI 2 (bypy)4 (HSiW12 O40 )2 ] ⋅ 14H2 O (2) and [AgI (bypy)(γ-Mo8 O26 )0.5 ] (3) (bypy⋅Cl=1-Benzyl-4,4'-bipyridyinium chloride). The structures were characterized by Fourier transform infrared spectroscopy (FT-IR), Powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS) and single crystal X-ray diffraction. Compounds 1-3 show excellent photochromic ability with fast photoresponse under the irradiation of ultraviolet light with different degrees of color changes. So compounds 1-3 can be used as visible ultraviolet detectors. Compounds 1-3 also possess photoluminescence properties with fast and excellent fluorescence quenching effect. Compounds 1-3 also can be used as inkless and erasable printing materials with suspensions of 1-3 applied to filter paper. Compounds 1-3 can also produce color changes in amine vapor environment, especially in an NH3 atmosphere. Compounds 1-3 can be used as organic amine detectors.

4.
PLoS Genet ; 15(6): e1008111, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31194729

RESUMO

Signal transduction activated by Wingless/Wnt ligands directs cell proliferation and fate specification in metazoans, and its overactivation underlies the development of the vast majority of colorectal cancers. In the conventional model, the secretion and movement of Wingless to cells distant from its source of synthesis are essential for long-range signaling in tissue patterning. However, this model was upended recently by an unanticipated finding: replacement of wild-type Drosophila Wingless with a membrane-tethered form produced viable adults with largely normal external morphology, which suggested that Wingless secretion and movement are dispensable for tissue patterning. Herein, we tested this foundational principle in the adult intestine, where Wingless signaling gradients coincide with all major boundaries between compartments. We find that the critical roles of Wingless during adult intestinal development, which include regulation of target gene activation, boundary formation, stem cell proliferation, epithelial cell fate specification, muscle differentiation, gut folding, and signaling crosstalk with the Decapentaplegic pathway, are all disrupted by Wingless tethering. These findings provide new evidence that supports the requirement for the direct, long-range action of Wingless in tissue patterning, with relevance for animal development, tissue homeostasis and Wnt-driven disease.


Assuntos
Padronização Corporal/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteína Wnt1/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Proliferação de Células/genética , Drosophila melanogaster/crescimento & desenvolvimento , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Homeostase , Intestinos/crescimento & desenvolvimento , Transdução de Sinais/genética , Células-Tronco/metabolismo
5.
Entropy (Basel) ; 24(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35741497

RESUMO

The migration and predation of grasshoppers inspire the grasshopper optimization algorithm (GOA). It can be applied to practical problems. The binary grasshopper optimization algorithm (BGOA) is used for binary problems. To improve the algorithm's exploration capability and the solution's quality, this paper modifies the step size in BGOA. The step size is expanded and three new transfer functions are proposed based on the improvement. To demonstrate the availability of the algorithm, a comparative experiment with BGOA, particle swarm optimization (PSO), and binary gray wolf optimizer (BGWO) is conducted. The improved algorithm is tested on 23 benchmark test functions. Wilcoxon rank-sum and Friedman tests are used to verify the algorithm's validity. The results indicate that the optimized algorithm is significantly more excellent than others in most functions. In the aspect of the application, this paper selects 23 datasets of UCI for feature selection implementation. The improved algorithm yields higher accuracy and fewer features.

6.
J Neurosci ; 40(6): 1186-1193, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024767

RESUMO

In vitro differentiation of pluripotent stem cells provides a systematic platform to study development and disease. Recent advances in brain organoid technology have created new opportunities to investigate the formation and function of the human brain, under physiological and pathological conditions. Brain organoids can be generated to model the cellular and structural development of the human brain, and allow the investigation of the intricate interactions between resident neural and glial cell types. Combined with new advances in gene editing, imaging, and genomic analysis, brain organoid technology can be applied to address questions pertinent to human brain development, disease, and evolution. However, the current iterations of brain organoids also have limitations in faithfully recapitulating the in vivo processes. In this perspective, we evaluate the recent progress in brain organoid technology, and discuss the experimental considerations for its utilization.Dual Perspectives Companion Paper: Integrating CRISPR Engineering and hiPSC-Derived 2D Disease Modeling Systems, by Kristina Rehbach, Michael B. Fernando, and Kristen J. Brennand.


Assuntos
Encéfalo/fisiologia , Organoides , Encéfalo/embriologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/fisiologia
7.
Vet Res ; 52(1): 3, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407892

RESUMO

Unlike the successful immunization of native H. contortus antigens that contributed to the realization of the first commercial vaccine Barbervax, not many studies revealed the encouraging protective efficacies of recombinant H. contortus antigens in laboratory trials or under field conditions. In our preliminary study, H. contortus α/ß-hydrolase domain protein (HcABHD) was demonstrated to be an immunomodulatory excretory-secretory (ES) protein that interacts with goat T cells. We herein evaluated the protective capacities of two HcABHD preparations, recombinant HcABHD (rHcABHD) antigen and anti-rHcABHD IgG, against H. contortus challenge via active and passive immunization trials, respectively. Parasitological parameter, antibody responses, hematological pathology and cytokine profiling in unchallenged and challenged goats were monitored and determined throughout both trials. Subcutaneous administration of rHcABHD with Freund adjuvants elicited protective immune responses in challenged goats, diminishing cumulative fecal egg counts (FEC) and total worm burden by 54.0% and 74.2%, respectively, whereas passive immunization with anti-rHcABHD IgG conferred substantial protection to challenged goats by generating a 51.5% reduction of cumulative FEC and a 73.8% reduction of total worm burden. Additionally, comparable changes of mucosal IgA levels, circulating IgG levels, hemoglobin levels, and serum interleukin (IL)-4 and IL-17A levels were observed in rHcABHD protein/anti-rHcABHD IgG immunized goats in both trials. Taken together, the recombinant version of HcABHD might have further application under field conditions in protecting goats against H. contortus infection, and the integrated immunological pipeline of ES antigen identification, screening and characterization may provide new clues for further development of recombinant subunit vaccines to control H. contortus.


Assuntos
Doenças das Cabras/parasitologia , Hemoncose/veterinária , Haemonchus/imunologia , Proteínas de Helminto/uso terapêutico , Vacinas/uso terapêutico , Animais , Antígenos de Helmintos/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Doenças das Cabras/prevenção & controle , Cabras , Hemoncose/prevenção & controle , Masculino , Contagem de Ovos de Parasitas/veterinária , Vacinas Sintéticas/uso terapêutico
8.
Parasitology ; 148(12): 1497-1508, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34193327

RESUMO

The prevention, treatment and control of Haemonchus contortus have been increasingly problematic due to its widespread occurrence and anthelmintic resistance. There are very few descriptions of recombinant antigens being protective for H. contortus, despite the success of various native antigen preparations, including Barbervax. We recently identified an H. contortus excretory­secretory antigen, H. contortus adhesion-regulating molecule 1 (HcADRM1), that served as an immunomodulator to impair host T-cell functions. Given the prophylactic potential of HcADRM1 protein as a vaccine candidate, we hereby assessed the efficacies of HcADRM1 preparations against H. contortus infection. Parasitological and immunological parameters were evaluated throughout all time points of the trials, including fecal egg counts (FEC), abomasal worm burdens, complete blood counts, cytokine production profiles and antibody responses. Active vaccination with recombinant HcADRM1 (rHcADRM1) protein induced protective immunity in inoculated goats, resulting in reductions of 48.9 and 58.6% in cumulative FEC and worm burdens. Simultaneously, passive administration of anti-HcADRM1 antibodies generated encouraging levels of protection with 46.7 and 56.2% reductions in cumulative FEC and worm burdens in challenged goats. In addition, HcADRM1 preparations-immunized goats showed significant differences in mucosal and serum antigen-specific immunoglobulin G (IgG) levels, total mucosal IgA levels, haemoglobin values and circulating interferon-γ, interleukin (IL)-4 and IL-17A production compared to control goats in both trials. The preliminary data of these laboratory trials validated the immunoprophylactic effects of rHcADRM1 protein. It can be pursued as a potential vaccine antigen to develop an effective recombinant subunit vaccine against H. contortus under field conditions.


Assuntos
Doenças das Cabras , Hemoncose , Haemonchus , Animais , Anticorpos Anti-Helmínticos , Cabras , Hemoncose/prevenção & controle , Hemoncose/veterinária
9.
PLoS Genet ; 14(2): e1007178, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29408853

RESUMO

The aberrant activation of Wnt signal transduction initiates the development of 90% of colorectal cancers, the majority of which arise from inactivation of the tumor suppressor Adenomatous polyposis coli (APC). In the classical model for Wnt signaling, the primary role of APC is to act, together with the concentration-limiting scaffold protein Axin, in a "destruction complex" that directs the phosphorylation and consequent proteasomal degradation of the transcriptional activator ß-catenin, thereby preventing signaling in the Wnt-off state. Following Wnt stimulation, Axin is recruited to a multiprotein "signalosome" required for pathway activation. Whereas it is well-documented that APC is essential in the destruction complex, APC's role in this complex remains elusive. Here, we demonstrate in Drosophila that Axin exists in two distinct phosphorylation states in Wnt-off and Wnt-on conditions, respectively, that underlie its roles in the destruction complex and signalosome. These two Axin phosphorylation states are catalyzed by glycogen synthase kinase 3 (GSK3), and unexpectedly, completely dependent on APC in both unstimulated and Wnt-stimulated conditions. In a major revision of the classical model, we show that APC is essential not only in the destruction complex, but also for the rapid transition in Axin that occurs after Wnt stimulation and Axin's subsequent association with the Wnt co-receptor LRP6/Arrow, one of the earliest steps in pathway activation. We propose that this novel requirement for APC in Axin regulation through phosphorylation both prevents signaling in the Wnt-off state and promotes signaling immediately following Wnt stimulation.


Assuntos
Proteína Axina/metabolismo , Proteínas do Citoesqueleto/fisiologia , Proteínas de Drosophila/fisiologia , Proteínas Wnt/metabolismo , Animais , Animais Geneticamente Modificados , Células Cultivadas , Proteínas do Citoesqueleto/genética , Drosophila/embriologia , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Embrião não Mamífero , Feminino , Fosforilação , Processamento de Proteína Pós-Traducional , Via de Sinalização Wnt
10.
J Contemp Dent Pract ; 22(1): 4-8, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34002700

RESUMO

AIM: The 75th anniversary of community water fluoridation in the United States was celebrated in 2020. However, there are studies that stimulate polarized discussion over the use of fluoride in dentistry. The purpose of this study was to evaluate dental and dental hygiene students' knowledge and perception of fluoride use in dentistry. MATERIALS AND METHODS: A survey was conducted to gauge participant's knowledge and perception of fluoride and their opinion on the need for developing viable alternatives to fluoride. An Institutional Review Board (IRB# 5190496) application was filed and approved. A hard copy survey was distributed to all student classes at Loma Linda University School of Dentistry (U.S.) between January 13, 2020, and February 5, 2020. Descriptive data were compiled and analyzed. Knowledge-based questions were compared using Kruskal-Wallis procedure to evaluate correct percentage among different classes. Perception questions were analyzed using a Likert scale and also a Chi-squared test. All tests were two-sided with α at 0.05. RESULTS: Out of 482 students, 282 students responded (58.5%). The mean of correct responses for knowledge ranged from 49 to 69%. There was a statistically significant difference among the classes. Overall the perception of the use of fluoride in dentistry was positive, and it changed with exposure to lectures on fluoride over the years. CONCLUSION: There was a correlation between knowledge and the perception of the use of fluoride in dentistry, indicating the importance of adequate delivery of didactic teaching on knowledge of fluoride to dental and dental hygiene students. CLINICAL SIGNIFICANCE: The oral healthcare provider plays a pivotal role in communicating pertinent information on the benefits of fluoride in preventing dental caries to the general public, prompting adequate delivery of didactic teaching on this topic in dental education.


Assuntos
Cárie Dentária , Fluoretos , Atitude do Pessoal de Saúde , Humanos , Higiene Bucal , Percepção , Estudantes de Odontologia
11.
Vet Res ; 51(1): 65, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32404195

RESUMO

Haemonchus contortus has evolved highly integrated and sophisticated mechanisms to promote coexistence with hosts. The excretory-secretory (ES) products generated by this parasite contribute to the regulation of the host immune response to facilitate immune evasion and induce chronicity, but the proteins responsible for this process and the exact cellular mechanisms have yet to be defined. In this study, we identified 114 H. contortus ES proteins (HcESPs) interacting with host T cells and 15 T cell binding receptors via co-immunoprecipitation and shotgun liquid chromatography-tandem mass spectrometry analysis. Based on bioinformatics analysis, we demonstrated that HcESPs could inhibit T cell viability, induce cell apoptosis, suppress T cell proliferation and cause cell cycle arrest. Furthermore, the stimulation of HcESPs exerted critical control effects on T cell cytokine production profiles, predominantly promoting the secretion of interleukin (IL)-10, IL-17A and transforming growth factor-ß1 and inhibiting IL-2, IL-4 and interferon-γ production. Collectively, these findings may provide insights into the interaction between ES proteins and key host effector cells, enhancing our understanding of the molecular mechanism underlying parasite immune evasion and providing new clues for novel vaccine development.


Assuntos
Haemonchus/fisiologia , Proteínas de Helminto/imunologia , Evasão da Resposta Imune , Linfócitos T/imunologia , Animais , Cabras/imunologia , Proteômica , Ratos , Ratos Sprague-Dawley
12.
Clin Lab ; 66(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32776747

RESUMO

BACKGROUND: The relationship between non-cholestatic liver disease and total bile acid (TBA) remains obscure. The present study aimed to verify this relationship in patients with non-cholestatic chronic hepatitis B virus (HBV) infection. METHODS: A total of 922 consecutive chronic HBV infected patients with alkaline phosphatase (ALP) ≤ 1.5 upper limit of normal (ULN) and gamma-glutamyl transferase (GGT) ≤ 3 ULN were rigorously included in this cross-sectional study. Liver biopsy was performed in 53 patients and Scheuer scoring system was used to evaluate inflammation grade. G3/G4 or Child-Pugh B/C were considered to be significant liver injury. RESULTS: Compared to Child-Pugh A, TBA, total bilirubin (TBIL), ALP, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and AST to ALT ratio (AST/ALT) were significantly higher in Child-Pugh B/C, while TBIL to TBA ratio (TBIL/TBA) was significantly lower (all p < 0.001). In multivariate analysis, TBA and AST/ALT were independently correlated with Child-Pugh B/C [odds ratio (OR) = 1.04, p < 0.001; OR = 1.79, p < 0.001, respectively]. The area under the curve (AUC) of TBA (0.82) was significantly higher than that of AST (0.73, p < 0.001) and ALT (0.63, p < 0.001). Furthermore, in patients with liver biopsy, TBA was also significantly higher in G3/G4 while TBIL/TBA was significantly lower (p < 0.05). After adjusting the factors related to bile excretion, TBIL/TBA was independently associated with G3/G4 (OR = 0.89, p = 0.037). CONCLUSIONS: Serum TBA shows a close relationship with significant liver injury in chronic HBV infected patients without cholestasis. Assessment of TBA, especially in combination with TBIL/TBA, may serve as a non-invasive marker for the diagnosis of non-cholestatic hepatic damage.


Assuntos
Colestase , Hepatite B Crônica , Alanina Transaminase , Ácidos e Sais Biliares , Estudos Transversais , Hepatite B Crônica/diagnóstico , Humanos , Fígado
13.
PLoS Genet ; 13(7): e1006870, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28708826

RESUMO

Wnt/ß-catenin signal transduction directs intestinal stem cell (ISC) proliferation during homeostasis. Hyperactivation of Wnt signaling initiates colorectal cancer, which most frequently results from truncation of the tumor suppressor Adenomatous polyposis coli (APC). The ß-catenin-TCF transcription complex activates both the physiological expression of Wnt target genes in the normal intestinal epithelium and their aberrantly increased expression in colorectal tumors. Whether mechanistic differences in the Wnt transcription machinery drive these distinct levels of target gene activation in physiological versus pathological states remains uncertain, but is relevant for the design of new therapeutic strategies. Here, using a Drosophila model, we demonstrate that two evolutionarily conserved transcription cofactors, Earthbound (Ebd) and Erect wing (Ewg), are essential for all major consequences of Apc1 inactivation in the intestine: the hyperactivation of Wnt target gene expression, excess number of ISCs, and hyperplasia of the epithelium. In contrast, only Ebd, but not Ewg, mediates the Wnt-dependent regulation of ISC proliferation during homeostasis. Therefore, in the adult intestine, Ebd acts independently of Ewg in physiological Wnt signaling, but cooperates with Ewg to induce the hyperactivation of Wnt target gene expression following Apc1 loss. These findings have relevance for human tumorigenesis, as Jerky (JRK/JH8), the human Ebd homolog, promotes Wnt pathway hyperactivation and is overexpressed in colorectal, breast, and ovarian cancers. Together, our findings reveal distinct requirements for Ebd and Ewg in physiological Wnt pathway activation versus oncogenic Wnt pathway hyperactivation following Apc1 loss. Such differentially utilized transcription cofactors may offer new opportunities for the selective targeting of Wnt-driven cancers.


Assuntos
Proteína B de Centrômero/genética , Proteínas do Citoesqueleto/genética , Proteínas de Drosophila/genética , Neoplasias/genética , Neuropeptídeos/genética , Proteínas Nucleares/biossíntese , Fatores de Transcrição/genética , Animais , Carcinogênese/genética , Proliferação de Células/genética , Proteína B de Centrômero/biossíntese , Proteínas de Ligação a DNA , Modelos Animais de Doenças , Proteínas de Drosophila/biossíntese , Epitélio/crescimento & desenvolvimento , Epitélio/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Humanos , Hiperplasia/genética , Hiperplasia/patologia , Intestinos/crescimento & desenvolvimento , Neoplasias/patologia , Neuropeptídeos/biossíntese , Proteínas Nucleares/genética , Proteínas de Ligação a RNA , Células-Tronco/metabolismo , Fatores de Transcrição/biossíntese , Via de Sinalização Wnt/genética
14.
Development ; 143(10): 1710-20, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27190037

RESUMO

Wnt/ß-catenin signaling controls intestinal stem cell (ISC) proliferation, and is aberrantly activated in colorectal cancer. Inhibitors of the ADP-ribose polymerase Tankyrase (Tnks) have become lead therapeutic candidates for Wnt-driven cancers, following the recent discovery that Tnks targets Axin, a negative regulator of Wnt signaling, for proteolysis. Initial reports indicated that Tnks is important for Wnt pathway activation in cultured human cell lines. However, the requirement for Tnks in physiological settings has been less clear, as subsequent studies in mice, fish and flies suggested that Tnks was either entirely dispensable for Wnt-dependent processes in vivo, or alternatively, had tissue-specific roles. Here, using null alleles, we demonstrate that the regulation of Axin by the highly conserved Drosophila Tnks homolog is essential for the control of ISC proliferation. Furthermore, in the adult intestine, where activity of the Wingless pathway is graded and peaks at each compartmental boundary, Tnks is dispensable for signaling in regions where pathway activity is high, but essential where pathway activity is relatively low. Finally, as observed previously for Wingless pathway components, Tnks activity in absorptive enterocytes controls the proliferation of neighboring ISCs non-autonomously by regulating JAK/STAT signaling. These findings reveal the requirement for Tnks in the control of ISC proliferation and suggest an essential role in the amplification of Wnt signaling, with relevance for development, homeostasis and cancer.


Assuntos
Adenosina Difosfato Ribose/metabolismo , Células-Tronco Adultas/citologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/enzimologia , Homeostase , Intestinos/citologia , Tanquirases/metabolismo , Células-Tronco Adultas/metabolismo , Animais , Proteína Axina/metabolismo , Diferenciação Celular , Proliferação de Células , Sistema Digestório/citologia , Enterócitos/metabolismo , Mutação/genética , Transdução de Sinais , Proteína Wnt1/metabolismo
15.
Inorg Chem ; 58(7): 4190-4200, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30883104

RESUMO

By using a 2,2'-dimethyl-4,4'-bithiazole (dm4bt) ligand, Keggin polyanions, and different metal ions, nine Keggin-based compounds, namely, {[Ag(dm4bt)2][Ag2(dm4bt)3]}2(PW12O40)(H2PWV2WVI10O40) (1), [CuI(dm4bt)2][CuII(dm4bt)2(PW12O40)] (2), [CuI(dm4bt)2]4(SiW12O40) (3), {[Zn(dm4bt)2]2(SiW12O40)} (4), [Zn(dm4bt)2(H2O)]2(HPMoV2MoVI10O40)·2H2O (5), [Zn(dm4bt)2(Mo2O7)] (6), [Cd(dm4bt)3][Cd(dm4bt)2(H2O)(PMo12O40)]2·2H2O (7), [Cd(dm4bt)3](PMo12O40)·(Hdm4bt) (8), and [Cd(dm4bt)2(H2O)2]2(HPMoV2MoVI10O40)·2H2O (9), have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, IR spectroscopy, and elemental analyses. Compounds 1-9 are zero-dimensional structures except compound 6, which exhibits a one-dimensional structure. In compound 1, there are three isolated subunits: Keggin anions, binuclear [Ag2(dm4bt)3]2+, and mononuclear [Ag(dm4bt)2]+ clusters. The binuclear [Ag2(dm4bt)3]2+ cluster has a Ag-Ag bond. In compound 2, a monosupporting anion {[CuII(dm4bt)2](PW12O40)}- and an isolated [Cu(dm4bt)2]+ cluster exist. By changing the transition metal ions, we obtained two different structures: a supramolecular 3 and a bisupporting anion in 4. By a one-pot method, we successfully obtained compounds 5 and 6, 7 and 8, respectively. In compound 5, the [Zn(dm4bt)2(H2O)]2+ subunit links adjacent PMo12 anions via S···O interactions to form a one-dimensional (1D) supramolecular chain. In compound 6, some PMo12 ions have transformed to [Mo2O7] n2 n- chains. The [Zn(dm4bt)2]2+ clusters buckle up and down the chain. Compound 7 has a monosupporting anion and an isolated [Cd(dm4bt)3]2+ cluster. Compound 8 has isolated anions and [Cd(dm4bt)3]2+ clusters. By changing the pH of 7 and 8, a distinct supramolecular compound 9 was obtained. Additionally, the optical band gap, electrochemical, and photocatalytic properties of 1-9 have been investigated in detail. The carbon paste electrodes can be used as bifunctional amperometric and fluorescence sensors for recognition of Hg2+. The n-CPEs as electrochemical sensors can show accurate selectivity for NO2- ions in some common ions. In the fluorescence sensor experiment, fluorescence intensities decrease more than 80% when quenched by Hg2+.

16.
PLoS Genet ; 12(2): e1005822, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26845150

RESUMO

Intestinal stem cell (ISC) self-renewal and proliferation are directed by Wnt/ß-catenin signaling in mammals, whereas aberrant Wnt pathway activation in ISCs triggers the development of human colorectal carcinoma. Herein, we have utilized the Drosophila midgut, a powerful model for ISC regulation, to elucidate the mechanisms by which Wingless (Wg)/Wnt regulates intestinal homeostasis and development. We provide evidence that the Wg signaling pathway, activation of which peaks at each of the major compartment boundaries of the adult intestine, has essential functions. Wg pathway activation in the intestinal epithelium is required not only to specify cell fate near compartment boundaries during development, but also to control ISC proliferation within compartments during homeostasis. Further, in contrast with the previous focus on Wg pathway activation within ISCs, we demonstrate that the primary mechanism by which Wg signaling regulates ISC proliferation during homeostasis is non-autonomous. Activation of the Wg pathway in absorptive enterocytes is required to suppress JAK-STAT signaling in neighboring ISCs, and thereby their proliferation. We conclude that Wg signaling gradients have essential roles during homeostasis and development of the adult intestine, non-autonomously controlling stem cell proliferation inside compartments, and autonomously specifying cell fate near compartment boundaries.


Assuntos
Linhagem da Célula , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Mucosa Intestinal/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Proteínas Wnt/metabolismo , Proteína Wnt1/metabolismo , Envelhecimento , Animais , Proliferação de Células , Enterócitos/citologia , Enterócitos/metabolismo , Epitélio/metabolismo , Homeostase , Intestinos/citologia , Janus Quinases/metabolismo , Larva/citologia , Músculos/metabolismo , Fatores de Transcrição STAT/metabolismo
17.
Trop Anim Health Prod ; 51(3): 719-722, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30269235

RESUMO

Bovine viral diarrhea virus (BVDV) and Mycobacterium avium subspecies paratuberculosis (MAP) are important pathogens, which cause serious disease in animals. However, information about BVDV and MAP infection in Tibetan sheep in China is limited. Two thousand one hundred and eighty-seven blood samples were collected from Tibetan sheep between April 2013 and March 2014 from the Tibetan Plateau and tested for BVDV and MAP antibodies using commercial ELISA kits. The overall seroprevalence of BVDV and MAP in Tibetan sheep was 36.7 and 11.29%, respectively. Furthermore, risk factor analysis indicated that the age of sheep was statistically significant associated with BVDV infection and the region was considered as the risk factor of MAP infection in sheep (P < 0.05), gender and season were not considered as risk factors. This is the first report of seroprevalence and risk factors associated with BVDV and MAP infection in Tibetan Sheep in China, which will provide baseline information for controlling BVDV and MAP infection in ruminants in the Tibetan Plateau, western China.


Assuntos
Mycobacterium avium subsp. paratuberculosis , Paratuberculose/epidemiologia , Doenças dos Ovinos/microbiologia , Animais , Anticorpos Antibacterianos , Anticorpos Antivirais , Vírus da Diarreia Viral Bovina , Ensaio de Imunoadsorção Enzimática/veterinária , Fatores de Risco , Estações do Ano , Estudos Soroepidemiológicos , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/virologia , Tibet/epidemiologia
18.
EMBO J ; 30(8): 1444-58, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21399610

RESUMO

Wnt/Wingless signal transduction directs fundamental developmental processes, and upon hyperactivation triggers colorectal adenoma/carcinoma formation. Responses to Wnt stimulation are cell specific and diverse; yet, how cell context modulates Wnt signalling outcome remains obscure. In a Drosophila genetic screen for components that promote Wingless signalling, we identified Earthbound 1 (Ebd1), a novel member in a protein family containing Centromere Binding Protein B (CENPB)-type DNA binding domains. Ebd1 is expressed in only a subset of Wingless responsive cell types, and is required for only a limited number of Wingless-dependent processes. In addition, Ebd1 shares sequence similarity and can be functionally replaced with the human CENPB domain protein Jerky, previously implicated in juvenile myoclonic epilepsy development. Both Jerky and Ebd1 interact directly with the Wnt/Wingless pathway transcriptional co-activators ß-catenin/Armadillo and T-cell factor (TCF). In colon carcinoma cells, Jerky facilitates Wnt signalling by promoting association of ß-catenin with TCF and recruitment of ß-catenin to chromatin. These findings indicate that tissue-restricted transcriptional co-activators facilitate cell-specific Wnt/Wingless signalling responses by modulating ß-catenin-TCF activity.


Assuntos
Proteína B de Centrômero/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição TCF/metabolismo , Transativadores/metabolismo , Proteínas Wnt/metabolismo , Proteína Wnt1/metabolismo , beta Catenina/metabolismo , Animais , Subunidade Apc1 do Ciclossomo-Complexo Promotor de Anáfase , Western Blotting , Células Cultivadas , Proteína B de Centrômero/genética , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Proteínas de Ligação a DNA , Drosophila/genética , Drosophila/crescimento & desenvolvimento , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Rim/citologia , Rim/metabolismo , Luciferases/metabolismo , Proteínas Nucleares/genética , Ligação Proteica , RNA Mensageiro/genética , Proteínas de Ligação a RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fatores de Transcrição TCF/genética , Transativadores/genética , Proteínas Wnt/genética , Proteína Wnt1/genética , beta Catenina/genética
19.
Chemistry ; 21(45): 16219-28, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26387571

RESUMO

Three series of copper-lanthanide/lanthanide coordination polymers (CPs) Ln(III) Cu(II) Cu(I) (bct)3 (H2 O)2 [Ln=La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Er (10), Yb (11), and Lu (12), H2 bct=2,5-bis(carboxymethylmercapto)-1,3,4-thiadiazole acid], Ln(III) Cu(I) (bct)2 [Ln=Ce (2 a), Pr (3 a), Nd (4 a), Sm (5 a), Eu (6 a), Gd (7 a), Tb (8 a), Dy (9 a), Er (10 a), Yb (11 a), and Lu (12 a)], and Ln(III) 2 (bct)3 (H2 O)5 [Ln=La (1 b), Ce (2 b), Pr (3 b), Nd (4 b), Sm (5 b), Eu (6 b), Gd (7 b), Tb (8 b), and Dy (9 b)] have been successfully constructed under hydrothermal conditions by modulating the reaction time. Structural characterization has revealed that CPs 1-12 possess a unique one-dimensional (1D) strip-shaped structure containing two types of double-helical chains and a double-helical channel. CPs 2 a-12 a show a three-dimensional (3D) framework formed by Cu(I) linking two types of homochiral layers with double-helical channels. CPs 1 b-9 b exhibit a 3D framework with single-helical channels. CPs 6 b and 8 b display visible red and green luminescence of the Eu(III) and Tb(III) ions, respectively, sensitized by the bct ligand, and microsecond-level lifetimes. CP 8 b shows a rare magnetic transition between short-range ferromagnetic ordering at 110 K and long-range ferromagnetic ordering below 10 K. CPs 9 a and 9 b display field-induced single-chain magnet (SCM) and/or single-molecule magnet (SMM) behaviors, with Ueff values of 51.7 and 36.5 K, respectively.

20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(6): 893-7, 2015 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-26679646

RESUMO

OBJECTIVE: To further demonstrate the interaction of a new 14-3-3 interaction protein hematopoietic progenitor kinase 1[HPK1]-interacting protein (HIP-55) and 14-3-3 proteins and its potential biological function in HEK293 cells. METHODS: PDEST-N-Venus-HIP-55WT (wild type),PDEST-N-Venus-HIP-55AA (mutants, S269A/T291A, abolishing the binding of HIP-55 to 14-3-3),PDEST-GST-HIP-55WT and PDEST-C-Venus-14-3-3τ plasmids were constructed by gateway system. Their expressions were demonstrated by Western blotting method. Then we used Bimolecular Fluorescence Complementation (BiFC) and co-immunoprecipitation (co-IP) methods to demonstrate the interaction of HIP-55 and 14-3-3 in HEK293 cells. Moreover, the 14-3-3 antagonist peptide, R18 and HIP-55 protein mutant plasmid HIP-55AA were used to detect the protein synthesis of HIP-55 at different time points induced by puromycin, an inhibitor of protein production. RESULTS: The HEK293 cells expressed HIP-55 protein respectively, after being transected with PDEST-N-Venus-HIP-55WT,PDEST-N-Venus-HIP-55AA,PDEST-GST-HIP-55WT plasmids and expressed 14-3-3 protein after being transected with PDEST-C-Venus-14-3-3τ plasmids. We could detect venus fluorescence of venus-HIP-55 protein via confocal microscopy in HEK 293 cells transfected with N-Venus-HIP-55 and C-14-3-3τ plasmids by BiFC, but not in HEK 293 cells transfected with N-Venus-HIP-55 AA (mutants S269A/T291A) and C-14-3-3τ plasmids. The results of BiFC suggested that 14-3-3 interacted with HIP-55 through HIP-55 S269/T291 sites. At the same time, the data of co-IP showed that there were endogenous interactions between 14-3-3 and HIP-55. Furthermore, puromycin had no influence in HIP-55 protein synthesis at hours 0, 4, or 8 in HEK 293 cells expressing GST-HIP-55WT and 14-3-3 plasmids, while puromycin blocked HIP-55 protein synthesis in HEK 293 cells transfected with N-Venus-HIP-55AA (mutants S269A/T291A) and C-14-3-3τ plasmids. The results indicated that the 14-3-3/HIP-55 complex could contributed to the stability of HIP-55. CONCLUSION: HIP-55 forms a complex with 14-3-3 and 14-3-3/HIP-55 interaction increases the stability of HIP-55.


Assuntos
Proteínas 14-3-3/química , Proteínas dos Microfilamentos/química , Western Blotting , Células HEK293 , Humanos , Microscopia Confocal , Microscopia de Fluorescência , Plasmídeos , Biossíntese de Proteínas , Estabilidade Proteica , Puromicina/química , Transfecção , Domínios de Homologia de src
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