Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
1.
Development ; 149(18)2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36134690

RESUMO

Heart regeneration requires multiple cell types to enable cardiomyocyte (CM) proliferation. How these cells interact to create growth niches is unclear. Here, we profile proliferation kinetics of cardiac endothelial cells (CECs) and CMs in the neonatal mouse heart and find that they are spatiotemporally coupled. We show that coupled myovascular expansion during cardiac growth or regeneration is dependent upon VEGF-VEGFR2 signaling, as genetic deletion of Vegfr2 from CECs or inhibition of VEGFA abrogates both CEC and CM proliferation. Repair of cryoinjury displays poor spatial coupling of CEC and CM proliferation. Boosting CEC density after cryoinjury with virus encoding Vegfa enhances regeneration. Using Mendelian randomization, we demonstrate that circulating VEGFA levels are positively linked with human myocardial mass, suggesting that Vegfa can stimulate human cardiac growth. Our work demonstrates the importance of coupled CEC and CM expansion and reveals a myovascular niche that may be therapeutically targeted for heart regeneration.


Assuntos
Células Endoteliais , Fator A de Crescimento do Endotélio Vascular , Animais , Proliferação de Células , Células Endoteliais/fisiologia , Coração/fisiologia , Humanos , Recém-Nascido , Camundongos , Miócitos Cardíacos/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
Retrovirology ; 18(1): 26, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34530855

RESUMO

BACKGROUND: Extracellular Vesicles (EV) recently have been implicated in the pathogenesis of HIV-1 syndromes, including neuroinflammation and HIV-1 associated neurological disorder (HAND). Cocaine, an illicit stimulant drug used worldwide is known to exacerbate these HIV-1 associated neurological syndromes. However, the effects of cocaine on EV biogenesis and roles of EVs in enhancing HIV-1 pathogenesis are not yet well defined. RESULTS: Here, we investigated the effects of cocaine on EV biogenesis and release in HIV-1 infected immune cells and explored their roles in elicitation of neuroinflammation. We found that cocaine significantly augmented the release of EVs from uninfected and HIV-1 infected T-cells, DCs and macrophages. Further analysis of the molecular components of EVs revealed enhanced expression of adhesion molecules integrin ß1 and LFA-1 in those EVs derived from cocaine treated cells. Intriguingly, in EVs derived from HIV-1 infected cells, cocaine treatment significantly increased the levels of viral genes in EVs released from macrophages and DCs, but not in T-cells. Exploring the molecular mechanism to account for this, we found that DCs and macrophages showed enhanced expression of the cocaine receptor Sigma 1-Receptor compared to T-cells. In addition, we found that cocaine significantly altered the integrity of the RNA-induced silencing complex (RISC) in HIV-1 infected macrophages and DCs compared to untreated HIV-1 infected cells. Characterizing further the molecular mechanisms involved in how cocaine increased EV release, we found that cocaine decreased the expression of the interferon-inducible protein BST-2; this resulted in altered trafficking of intracellular virus containing vesicles and EV biogenesis and release. We also observed EVs released from cocaine treated HIV-1 infected macrophages and DCs enhanced HIV-1 trans-infection to T-cells compared to those from untreated and HIV-1 infected cells. These EVs triggered release of proinflammatory cytokines in human brain microvascular endothelial cells (HBMECs) and altered monolayer integrity. CONCLUSIONS: Taken together, our results provide a novel mechanism which helps to elucidate the enhanced prevalence of neurological disorders in cocaine using HIV-1 infected individuals and offers insights into developing novel therapeutic strategies against HAND in these hosts.


Assuntos
Cocaína/efeitos adversos , Cocaína/imunologia , Células Dendríticas/efeitos dos fármacos , Vesículas Extracelulares/efeitos dos fármacos , HIV-1/imunologia , Macrófagos/efeitos dos fármacos , Doenças Neuroinflamatórias/complicações , Encéfalo/citologia , Cocaína/farmacologia , Citocinas/imunologia , Células Dendríticas/virologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Células Endoteliais/virologia , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Inflamação , Macrófagos/imunologia , Macrófagos/virologia , Biogênese de Organelas
3.
Cureus ; 15(11): e48523, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38073916

RESUMO

Carcinoma of the prostate is the second most common cancer in males, while multiple myeloma is the 17th most common cancer. The synchronous diagnosis of multiple myeloma and carcinoma of the prostate is a sporadic phenomenon with scarce published literature and a diagnostic and therapeutic dilemma. Here, we present a case of synchronous diagnosis of IgG and lambda subtypes of multiple myeloma with multiple lytic lesions, the revised international staging system (R-ISS 2), and non-metastatic acinar adenocarcinoma prostate, a very high-risk category. The patient received 25 weekly doses of cyclophosphamide, bortezomib, and dexamethasone (CyBorD)-based chemotherapy for myeloma and androgen deprivation therapy with injection leuprolide for prostate cancer. After reasonable disease control, the patient underwent an autologous stem cell transplant for multiple myeloma with melphalan at 140 mg/m2 and was offered definitive radiation therapy for prostate cancer. The potential association between carcinoma of the prostate and multiple myeloma has been hypothesized because of similarities in the tumor microenvironment. There are possible common biological pathways leading to co-stimulatory mechanisms, like interleukin-2 (IL-2), insulin-like growth factor 1 (IGF-1), stromal cell-derived factor 1 (SDF-1), and vascular endothelial growth factor (VEGF). However, they are not proven and warrant further research. This case highlights key areas of diagnosis and management of this sporadic occurrence, along with literature analysis and the need for further research, and is likely to be beneficial for clinicians in decision-making in future cases.

4.
Cureus ; 15(10): e47085, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38022018

RESUMO

Hairy cell leukemia variant (HCLv) is a sporadic, B-cell non-Hodgkin lymphoma classified under chronic lymphoproliferative disorders. HCLv usually presents with easy fatigue, dragging pain abdomen, anemia, splenomegaly, hepatomegaly, initially leukocytosis followed by leucopenia, hairy cells in the smear and bone marrow, and an increased risk of infections. There is hypercellular bone marrow, and cytopenias are secondary to hypersplenism. It is essential to differentiate HCL from disorders like classic hairy cell leukemia (HCLc), splenic marginal zone lymphoma, and splenic diffuse red pulp lymphoma, as these are biologically different, with divergent approaches and outcomes. HCLv is poorly responsive or primary refractory to standard purine analogs cladribine or pentostatin. It has lower response rates to even cladribine and rituximab combination, a standard of care for classic HCL with very good response rates. Here, we present a case of an elderly male who presented with splenomegaly and leukocytosis, diagnosed as HCLv, and was treated with a cladribine and rituximab-based regime but showed residual cells in bone marrow on flow cytometry at six months post-treatment. There were no residual cells in peripheral blood in flow cytometry. Various aspects of the disease are discussed here with a detailed literature analysis. There is a definite unmet need for research on better treatment options in HCLv to improve its overall outcome.

5.
Nucleic Acids Res ; 38(2): e9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19875416

RESUMO

Genomic technologies, such as array comparative genomic hybridization (aCGH), increasingly offer definitive gene dosage profiles in clinical samples. Historically, copy number profiling was limited to large fresh-frozen tumors where intact DNA could be readily extracted. Genomic analyses of pre-neoplastic tumors and diagnostic biopsies are often limited to DNA processed by formalin-fixation and paraffin-embedding (FFPE). We present specialized protocols for DNA extraction and processing from FFPE tissues utilizing DNase processing to generate randomly fragmented DNA. The protocols are applied to FFPE clinical samples of varied tumor types, from multiple institutions and of varied block age. Direct comparative analyses with regression coefficient were calculated on split-sample (portion fresh/portion FFPE) of colorectal tumor samples. We show equal detection of a homozygous loss of SMAD4 at the exon-level in the SW480 cell line and gene-specific alterations in the split tumor samples. aCGH application to a set of archival FFPE samples of skin squamous cell carcinomas detected a novel hemizygous deletion in INPP5A on 10q26.3. Finally we present data on derivative of log ratio, a particular sensitive detector of measurement variance, for 216 sequential hybridizations to assess protocol reliability over a wide range of FFPE samples.


Assuntos
Hibridização Genômica Comparativa/métodos , Dosagem de Genes , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , DNA/isolamento & purificação , Fragmentação do DNA , Desoxirribonucleases , Éxons , Fixadores , Formaldeído , Humanos , Inclusão em Parafina , Neoplasias Cutâneas/genética
6.
Indian J Pathol Microbiol ; 65(2): 396-400, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35435378

RESUMO

Carcinoma cervix usually spreads directly to contiguous structures, such as the vagina, urinary bladder, ureter, and rectum. Intestinal metastasis from cervical cancer is very uncommon and accounts for less than 4% of cases and to date, 24 cases have been reported in Medical literature. These may be asymptomatic or present with features of intestinal obstruction, bowel wall perforation, and mimic acute abdomen. Intestinal metastasis is a late occurrence and carries a poor prognosis, hence a high index of suspicion with prompt diagnosis and management is essential. We report a series of five patients with squamous cell carcinoma (SCC) of the cervix with intestinal metastasis diagnosed in our hospital.


Assuntos
Carcinoma de Células Escamosas , Obstrução Intestinal , Neoplasias do Colo do Útero , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/secundário , Colo do Útero/patologia , Feminino , Humanos , Intestinos/patologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia
7.
J Family Med Prim Care ; 11(10): 6529-6532, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36618238

RESUMO

COVID-19 disease has been associated with fungal infections such as aspergillosis and mucormycosis, especially in diabetic patients who have suffered from a moderately severe form of COVID-19 infection and are treated with steroids. Though there are multiple case reports describing co-infection with mucormycosis during the second wave of the COVID outbreak, the report of a dual fungal infection along with superadded bacterial infection is rare. Here we report a case where the same patient had a fungal storm with aspergillosis and mucormycosis and superadded Klebsiella. She was treated aggressively with antifungal agents, antibiotics, surgical debridement, and other supportive care. She improved and was discharged from the hospital after a long stay. She is being followed up regularly in the outpatient department and doing well.

8.
Blood ; 114(17): 3588-600, 2009 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-19700666

RESUMO

Targeting dendritic cell (DC) functions such as migration is a pivotal mechanism used by HIV-1 to disseminate within the host. The HIV-1 envelope protein is the most important of the virally encoded proteins that exploits the migratory capacity of DCs. In the present study, we elucidated the signaling machinery involved in migration of immature DCs (iDCs) in response to HIV-1 envelope protein. We observed that M-tropic HIV-1 glycoprotein 120 (gp120) induces phosphorylation of the nonreceptor tyrosine kinase, Pyk2. Inhibition of Pyk2 activity using a pharmacologic inhibitor, kinase-inactive Pyk2 mutant, and Pyk2-specific small interfering RNA blocked gp120-induced chemotaxis, confirming the role of Pyk2 in iDC migration. In addition, we also illustrated the importance of Pyk2 in iDC migration induced by virion-associated envelope protein, using aldithriol-2-inactivated M-tropic HIV-1 virus. Further analysis of the downstream signaling mechanisms involved in gp120-induced migration revealed that Pyk2 activates p38 mitogen-activated protein kinase, which in turn activates the F-actin-binding protein, leukocyte-specific protein 1, and enhances its association with actin. Taken together, our studies provide an insight into a novel gp120-mediated pathway that regulates DC chemotaxis and contributes to the dissemination of HIV-1 within an infected person.


Assuntos
Movimento Celular , Células Dendríticas/metabolismo , Quinase 2 de Adesão Focal/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Western Blotting , Quimiotaxia , Citometria de Fluxo , Quinase 2 de Adesão Focal/antagonistas & inibidores , Quinase 2 de Adesão Focal/genética , Proteína gp120 do Envelope de HIV/genética , Humanos , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas dos Microfilamentos/genética , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Receptores CCR5/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tirfostinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética
9.
Cureus ; 13(12): e20475, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35047294

RESUMO

Mucormycosis is an emerging infection in the present post-COVID-19 era, associated with high morbidity and mortality. We are reporting an interesting case of invasive rhino-orbital-cerebral mucormycosis in a 65-year-old female who presented with left nasal and orbital swelling after COVID-19 infection associated with uncontrolled diabetes mellitus. Histopathological and microbiology examination favored mucormycosis. Finally, endoscopic debridement of the lesion was done with left orbital exenteration. The patient at present is clinically stable. As these cases have been seen in many suspected and confirmed COVID-19 cases, early diagnosis and treatment will salvage the patient.

10.
J Surg Res ; 159(1): 509-16, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19375720

RESUMO

BACKGROUND: Non-well-differentiated cutaneous squamous cell carcinomas may display a more aggressive behavior. It is important to better define prognostic criteria for these tumors. METHODS: This was a retrospective case-control analysis of a squamous cell carcinoma database. Patients with non-well-differentiated and well-differentiated tumors were matched based on site of tumor, age, and immunocompromised status. Comparisons included demographics, histology, immunohistochemical protein expressions (Ki-67, p53, E-cadherin, cyclin D1), and clinical outcomes. RESULTS: Demographic features were similar between cases (n=30) and controls (n=30). Non-well-differentiated tumors were larger (1.8 cm versus 1.3 cm, P=0.08), deeper (0.81 cm versus 0.32 cm, P<0.0001), and had greater recurrence (P=0.003). Non-well-differentiated tumors showed increased proliferation rate, Ki-67 index (77% versus 61%, P=0.001); no significant difference in activity of p53, E-cadherin, and cyclin D1 between the two groups. CONCLUSIONS: Tumor differentiation and depth are important pathologic and prognostic criteria for cutaneous squamous cell carcinoma. Immunohistochemistry helps describe patterns of biomarker protein expression and may exemplify aggressive subtypes.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Cutâneas/patologia , Pele/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Pele/metabolismo , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/metabolismo
11.
Front Immunol ; 11: 136, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117283

RESUMO

Methamphetamine (Meth) abuse is a worldwide public health problem and contributes to HIV-1 pathobiology and poor adherence to anti-retroviral therapies. Specifically, Meth is posited to alter molecular mechanisms to provide a more conducive environment for HIV-1 replication and spread. Enhanced expression of inflammatory cytokines, such as Interleukin-1ß (IL-1ß), has been shown to be important for HIV-1 pathobiology. In addition, microRNAs (miRNAs) play integral roles in fine-tuning the innate immune response. Notably, the effects of Meth abuse on miRNA expression are largely unknown. We studied the effects of Meth on IL-1ß and miR-146a, a well-characterized member of the innate immune signaling network. We found that Meth induces miR-146a and triggers an IL-1ß auto-regulatory loop to modulate innate immune signaling in CD4+ T-cells. We also found that Meth enhances HIV-1 replication via IL-1 signaling. Our results indicate that Meth activates an IL-1ß feedback loop to alter innate immune pathways and favor HIV-1 replication. These observations offer a framework for designing targeted therapies in HIV-infected, Meth using hosts.


Assuntos
Linfócitos T CD4-Positivos/virologia , Estimulantes do Sistema Nervoso Central/toxicidade , HIV-1/efeitos dos fármacos , Interleucina-1beta/metabolismo , Metanfetamina/toxicidade , Replicação Viral/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Células Cultivadas , Retroalimentação Fisiológica/efeitos dos fármacos , Retroalimentação Fisiológica/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , HIV-1/imunologia , Humanos , MicroRNAs/biossíntese , MicroRNAs/efeitos dos fármacos
12.
FEBS Lett ; 594(12): 1947-1959, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32279313

RESUMO

Human immunodeficiency virus type 1 (HIV-1) subverts intracellular trafficking pathways to avoid its degradation and elimination, thereby enhancing its survival and spread. The molecular mechanisms involved in intracellular transport of HIV-1 are not yet fully defined. We demonstrate that the actin-binding protein lymphocyte-specific protein 1 (LSP1) interacts with the interferon-inducible protein bone marrow stromal antigen 2 (BST-2) in dendritic cells (DCs) to facilitate both endocytosis of surface-bound HIV-1 and the formation of early endosomes. Analysis of the molecular interaction between LSP1 and BST-2 reveals that the N terminus of LSP1 interacts with BST-2. Overall, we identify a novel mechanism of intracellular trafficking of HIV-1 in DCs centering on the LSP1/BST-2 complex. We also show that the HIV-1 accessory protein Vpu subverts this pathway by inducing proteasomal degradation of LSP1, augmenting cell-cell transmission of HIV-1.


Assuntos
Antígenos CD/metabolismo , Células Dendríticas/virologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Proteínas dos Microfilamentos/metabolismo , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Endocitose , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Proteínas Ligadas por GPI/metabolismo , Infecções por HIV/transmissão , Interações Hospedeiro-Patógeno/fisiologia , Proteínas do Vírus da Imunodeficiência Humana/metabolismo , Humanos , Interferon-alfa/farmacologia , Proteínas dos Microfilamentos/genética , Proteínas Virais Reguladoras e Acessórias/metabolismo
13.
Virusdisease ; 31(2): 179-193, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32656311

RESUMO

The recent outbreak of COVID-19 caused by SARS-CoV-2 brought a great global public health and economic concern. SARS-CoV-2 is an enveloped RNA virus, from the genus Betacoronavirus. Although few molecules have been tested and shown some efficacy against SARS-CoV-2 in humans but a safe and cost-effective attachment inhibitors are still required for the treatment of COVID-19. Natural products are gaining attention because of the large therapeutic window and potent antiviral, immunomodulatory, anti-inflammatory, and antioxidant properties. Therefore, this study was planned to screen natural products from Ayurveda that have the potential to modulate host immune system as well as block the virus entry in host cells by interfering its interaction with cellular receptor and may be used to develop an effective and broad-spectrum strategy for the management of COVID-19 as well as other coronavirus infections in coming future. To decipher the antiviral activity of the selected natural products, molecular docking was performed. Further, the drug-likeness, pharmacokinetics and toxicity parameters of the selected natural products were determined. Docking results suggest that curcumin and nimbin exhibits highest interaction with spike glycoprotein (MolDock score - 141.36 and - 148.621 kcal/mole) and ACE2 receptor (MolDock score - 142.647 and - 140.108 kcal/mole) as compared with other selected natural products/drugs and controls. Also, the pharmacokinetics data illustrated that all selected natural products have better pharmacological properties (low molecular weight; no violation of Lipinski rule of five, good absorption profiles, oral bioavailability, good blood-brain barrier penetration, and low toxicity risk). Our study exhibited that curcumin, nimbin, withaferin A, piperine, mangiferin, thebaine, berberine, and andrographolide have significant binding affinity towards spike glycoprotein of SARS-CoV-2 and ACE2 receptor and may be useful as a therapeutic and/or prophylactic agent for restricting viral attachment to the host cells. However, few other natural products like resveratrol, quercetin, luteolin, naringenin, zingiberene, and gallic acid has the significant binding affinity towards ACE2 receptor only and therefore may be used for ACE2-mediated attachment inhibition of SARS-CoV-2.

14.
Virusdisease ; 31(1): 13-21, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32206694

RESUMO

The emergence of 2019 novel coronavirus (2019-nCoV) is of global concern and might have emerged from RNA recombination among existing coronaviruses. CoV spike (S) protein which is crucial for receptor binding, membrane fusion via conformational changes, internalization of the virus, host tissue tropism and comprises crucial targets for vaccine development, remain largely uncharacterized. Therefore, the present study has been planned to determine the sequence variation, structural and antigenic divergence of S glycoprotein which may be helpful for the management of 2019-nCoV infection. The sequences of spike glycoprotein of 2019-nCoV and SARS coronavirus (SARS-CoV) were used for the comparison. The sequence variations were determined using EMBOSS Needle pairwise sequence alignment tools. The variation in glycosylation sites was predicted by NetNGlyc 1.0 and validated by N-GlyDE server. Antigenicity was predicted by NetCTL 1.2 and validated by IEDB Analysis Resource server. The structural divergence was determined by using SuperPose Version 1.0 based on cryo-EM structure of the SARS coronavirus spike glycoprotein. Our data suggests that 2019-nCoV is newly spilled coronavirus into humans in China is closely related to SARS-CoV, which has only 12.8% of difference with SARS-CoV in S protein and has 83.9% similarity in minimal receptor-binding domain with SARS-CoV. Addition of a novel glycosylation sites were observed in 2019-nCoV. In addition, antigenic analysis proposes that great antigenic differences exist between both the viral strains, but some of the epitopes were found to be similar between both the S proteins. In spite of the variation in S protein amino acid composition, we found no significant difference in their structures. Collectively, for the first time our results exhibit the emergence of human 2019-nCoV is closely related to predecessor SARS-CoV and provide the evidence that 2019-nCoV uses various novel glycosylation sites as SARS-CoV and may have a potential to become pandemic owing its antigenic discrepancy. Further, demonstration of novel Cytotoxic T lymphocyte epitopes may impart opportunities for the development of peptide based vaccine for the prevention of 2019-nCoV.

15.
Int J Cancer ; 124(10): 2270-80, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19173296

RESUMO

Elevated deoxycholic acid (DCA), mutations in the adenomatous polyposis coli (APC) gene and chronic inflammation are associated with increased risk of colorectal cancer. APC status was manipulated to determine whether DCA mediates inflammatory molecules in normal or initiated colonic mucosa. DCA increased steady state mRNA and protein levels of CXCL8 in cells which do not express wild-type APC. Steady-state CXCL8 mRNA and protein were suppressed when cells with conditional expression of wild-type APC were exposed to DCA. Immunostaining did not detect CXCL8 in normal human colonic mucosa. CXCL8 was expressed in adenomatous polyps and adenocarcinomas. CXCL8 expression correlated with nuclear beta-catenin localization in epithelial cells of adenomas, but was associated with endothelial cells and neutrophils in the adenocarcinomas. DCA-mediated CXCL8 promoter-reporter activity was elevated in a mutant APC background. Wild-type APC suppressed this effect. Mutation of activator protein-1 (AP-1) or nuclear factor kappa B (NF-kappaB) sites suppressed the activation of the CXCL8 promoter-reporter by DCA. Chromatin immunoprecipitation revealed that AP-1 and NF-kappaB binding to the 5'-promoter of CXCL8 was induced by DCA. The beta-catenin transcription factor was bound to the 5'-promoter of CXCL8 in the absence or presence of DCA. Phenotypic assays determined that DCA-mediated invasion was blocked by antibody-directed against CXCL8 or wild-type APC. CXCL8 exposure led to matrix metalloproteinase-2 production and increased invasion on laminin-coated filters. These data suggest that DCA-mediated CXCL8 occurs in initiated colonic epithelium and neutralizing CXCL8 could reduce the invasive potential of tumors.


Assuntos
Neoplasias Colorretais/genética , Ácido Desoxicólico/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes APC , Interleucina-8/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Primers do DNA , Humanos , Imuno-Histoquímica , Interleucina-8/genética , RNA Mensageiro/genética , Transcrição Gênica/efeitos dos fármacos
16.
Am J Gastroenterol ; 104(2): 302-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19174784

RESUMO

OBJECTIVES: Barrett's esophagus (BE) is a metaplastic lesion characterized by replacement of the normal squamous epithelium by columnar intestinal epithelium containing goblet cells. It is speculated that this process is an adaptation to protect cells from components of refluxate, such as gastric acid and bile acids. In contrast to the normal squamous epithelium, enterocytes of the distal ileum are adapted to transport bile acids from the intestinal lumen. Several bile acid transporters are utilized for effective removal of bile acids, including the apical sodium-dependent bile acid transporter (ASBT), the ileal bile acid-binding protein (IBABP), and the multidrug-resistant protein 3 (MRP3). We hypothesized that one of the possible functions of newly arising metaplastic epithelium, in the esophagus, is to transport bile acids. Our major goal was to evaluate the expression of bile acid transporters in normal squamous epithelium, BE with different grades of dysplasia, and esophageal adenocarcinoma (EAC). METHODS: A total of 101 patients were included in this study. Immunohistochemistry (IHC) and reverse transcriptase (RT)-PCR were used to detect the expression of these transporters at the mRNA and protein levels. RESULTS: Our immunohistochemical studies showed that all three bile acid transporters are expressed in BE glands, but not in squamous epithelium. ASBT was found in the apical border in BE biopsies. The highest frequency of ASBT expression was in patients with nondysplastic BE (9 of 15, 60%), and a progressive loss of ASBT was observed through the stages of dysplasia. ASBT was not detected in EAC (0 of 15). IBABP staining was observed in the cytoplasm of BE epithelial surface cells. Expression of IBABP was found in 100% of nondysplastic BE (14 of 14), in 93% of low-grade dysplasia (LGD, 15 of 16), in 73% of high-grade dysplasia (HGD, 10 of 14), and in 33% of EAC (5 of 15). MRP3 was expressed in the basolateral membrane in 93% of nondysplastic BE (13 of 14), in 60% of LGD (10 of 16), and in 86% of HGD (11 of 13). Only weak MRP3 staining was detected in EAC biopsies (5 of 15, 33%). In addition, RT-PCR studies showed increased expression of mRNA coding for ASBT (6.1x), IBABP (9.1x), and MRP3 (2.4x) in BE (N=13) compared with normal squamous epithelium (N=15). Significantly increased mRNA levels of IBABP (10.1x) and MRP3 (2.5x) were also detected in EAC (N=21) compared with normal squamous epithelium. CONCLUSIONS: We found that bile acid transporters expression is increased in BE tissue at the mRNA and protein levels and that expression of bile acid transporter proteins decreased with progression to cancer.


Assuntos
Adenocarcinoma/metabolismo , Esôfago de Barrett/metabolismo , Proteínas de Transporte/metabolismo , Neoplasias Esofágicas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Simportadores/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Proteínas de Transporte/genética , Estudos de Casos e Controles , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Glicoproteínas de Membrana/genética , Metaplasia , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Simportadores/genética
17.
Nanomaterials (Basel) ; 9(8)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362355

RESUMO

Sodium superionic conductor (NASICON)-type lithium aluminum germanium phosphate (LAGP) has attracted increasing attention as a solid electrolyte for all-solid-state lithium-ion batteries (ASSLIBs), due to the good ionic conductivity and highly stable interface with Li metal. However, it still remains challenging to achieve high density and good ionic conductivity in LAGP pellets by using conventional sintering methods, because they required high temperatures (>800 °C) and long sintering time (>6 h), which could cause the loss of lithium, the formation of impurity phases, and thus the reduction of ionic conductivity. Herein, we report the utilization of a spark plasma sintering (SPS) method to synthesize LAGP pellets with a density of 3.477 g cm-3, a relative high density up to 97.6%, and a good ionic conductivity of 3.29 × 10-4 S cm-1. In contrast to the dry-pressing process followed with high-temperature annealing, the optimized SPS process only required a low operating temperature of 650 °C and short sintering time of 10 min. Despite the least energy and short time consumption, the SPS approach could still achieve LAGP pellets with high density, little voids and cracks, intimate grain-grain boundary, and high ionic conductivity. These advantages suggest the great potential of SPS as a fabrication technique for preparing solid electrolytes and composite electrodes used in ASSLIBs.

18.
Sci Rep ; 9(1): 958, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700725

RESUMO

Methamphetamine (Meth) exacerbates HIV-1 pathobiology by increasing virus transmission and replication and accelerating clinical progression to AIDS. Meth has been shown to alter the expression of HIV-1 co-receptors and impair intrinsic resistance mechanisms of immune cells. However, the exact molecular mechanisms involved in augmenting HIV-1 replication in T-cells are still not yet clear. Here, we demonstrate that pretreatment with Meth of CD4+ T-cells enhanced HIV-1 replication. We observed upregulation of CD4+ T-cell activation markers and enhanced expression of miR-34c-5p and miR-155 in these cells. Further, we noted activation of the sigma-1 receptor and enhanced intracellular Ca2+ concentration and cAMP release in CD4+ T-cells upon Meth treatment, which resulted in increased phosphorylation and nuclear translocation of transcription factors NFκB, CREB, and NFAT1. Increased gene expression of IL-4 and IL-10 was also observed in Meth treated CD4+ T-cells. Moreover, proteasomal degradation of Ago1 occurred upon Meth treatment, further substantiating the drug as an activator of T-cells. Taken together, these findings show a previously unreported mechanism whereby Meth functions as a novel T-cell activator via the sigma-1 signaling pathway, enhancing replication of HIV-1 with expression of miR-34c-5p, and transcriptional activation of NFκB, CREB and NFAT1.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/fisiologia , Metanfetamina/farmacologia , Receptores sigma/metabolismo , Proteínas Argonautas/metabolismo , Biomarcadores/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Cálcio/metabolismo , Núcleo Celular/metabolismo , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , HIV-1/efeitos dos fármacos , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Fosforilação/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Receptores Dopaminérgicos/metabolismo , Replicação Viral/efeitos dos fármacos , Receptor Sigma-1
19.
Sci Rep ; 9(1): 6326, 2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31004105

RESUMO

Cerium dioxide (CeO2) is a surrogate material for traditional nuclear fuels and an essential material for a wide variety of industrial applications both in its bulk and nanometer length scale. Despite this fact, the underlying physics of thermal conductivity (kL), a crucial design parameter in industrial applications, has not received enough attention. In this article, a systematic investigation of the phonon transport properties was performed using ab initio calculations unified with the Boltzmann transport equation. An extensive examination of the phonon mode contribution, available three-phonon scattering phase space, mode Grüneisen parameter and mean free path (MFP) distributions were also conducted. To further augment theoretical predictions of the kL, measurements were made on specimens prepared by spark plasma sintering using the laser flash technique. Since the sample porosity plays a vital role in the value of measured kL, the effect of porosity on kL by molecular dynamics (MD) simulations were investigated. Finally, we also determined the nanostructuring effect on the thermal properties of CeO2. Since CeO2 films find application in various industries, the dependence of thickness on the in-plane and cross-plane kL for an infinite CeO2 thin film was also reported.

20.
Clin Cancer Res ; 13(18 Pt 1): 5305-13, 2007 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17875759

RESUMO

OBJECTIVES: The molecular factors contributing to the development of Barrett's esophagus (BE) are unclear. Our previous studies showed that BE tissues secrete interleukin-6 (IL-6) and express proteins associated with IL-6 signaling, including IL-6 receptor, activated signal transducer and activators of transcription 3 (STAT3), and antiapoptotic proteins Bcl-x(L) and Mcl-1. Here, we test the hypothesis that bile acids and gastric acids, two components of refluxate associated with gastresophageal reflux disease, activate the IL-6/STAT3 pathway. MATERIALS AND METHODS: Immunohistochemistry was used to assess levels of phosphorylated STAT3 in esophageal tissue samples from BE patients with different grades of dysplasia. Seg-1 esophageal adenocarcinoma cells were evaluated for STAT3 activation and IL-6 and Bcl-x(L) expression by molecular biology techniques, including Western blot, reverse transcription-PCR, and ELISA after exposure to control media (pH 7.4), media supplemented with a 0.1 mmol/L bile acid cocktail with media at pH 4 or media at pH 4 with bile acid cocktail. RESULTS: Immunohistochemical analysis showed that activated, phosphorylated STAT3 is expressed in nuclei of dysplastic BE and cancer tissues. Treatment of Seg-1 cells with media containing bile acid cocktail and acidified to pH 4 resulted in increased activation of STAT3, IL-6 secretion, and increased expression of Bcl-x(L). Inhibition of the STAT3 pathway using STAT3 small interfering RNA or Janus-activated kinase inhibitor resulted in increased apoptosis. CONCLUSIONS: The IL-6/STAT3 antiapoptotic pathway is induced by short exposure to bile acid cocktail and low pH. This alteration, if persistent in vivo, may underlie the development of dysplastic BE and tumor progression.


Assuntos
Esôfago de Barrett/metabolismo , Ácidos e Sais Biliares/metabolismo , Esôfago/metabolismo , Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Adenocarcinoma/química , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Esôfago de Barrett/patologia , Ácidos e Sais Biliares/farmacologia , Neoplasias Esofágicas/química , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Esôfago/efeitos dos fármacos , Esôfago/patologia , Feminino , Ácido Gástrico/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Interleucina-6/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Fator de Transcrição STAT3/análise , Fator de Transcrição STAT3/genética , Células Tumorais Cultivadas , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA