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1.
J Antimicrob Chemother ; 78(11): 2653-2659, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37681452

RESUMO

BACKGROUND: Feminizing hormone therapy (FHT) is essential to many trans women. Concern about negative drug interactions between FHT and ART can be an ART adherence barrier among trans women with HIV. OBJECTIVES: In this single-centre, parallel group, cross-sectional pilot study, we measured serum oestradiol concentrations in trans women with HIV taking FHT and unboosted integrase strand transfer inhibitor (INSTI)-based ART versus trans women without HIV taking FHT. METHODS: We included trans women with and without HIV, aged ≥18 years, taking ≥2 mg/day of oral oestradiol for at least 3 months plus an anti-androgen. Trans women with HIV were on suppressive ART ≥3 months. Serum oestradiol concentrations were measured prior to medication dosing and 2, 4, 6 and 8 h post-dose. Median oestradiol concentrations were compared between groups using Wilcoxon rank-sum tests. RESULTS: Participants (n = 8 with HIV, n = 7 without) had a median age of 32 (IQR: 28, 39) years. Among participants, the median oral oestradiol dose was 4 mg (range 2-6 mg). Participants had been taking FHT for a median of 4 years (IQR: 2, 8). Six trans women with HIV were taking bictegravir/emtricitabine/tenofovir alafenamide and two were taking dolutegravir/abacavir/lamivudine. All oestradiol concentrations were not significantly different between groups. Eleven (73%) participants had target oestradiol concentrations in the range 200-735 pmol/L at C4h (75% among women with HIV, 71% among those without HIV). CONCLUSIONS: Oestradiol concentrations were not statistically different in trans women with HIV compared with those without HIV, suggesting a low probability of clinically relevant drug-drug interactions between FHT and unboosted INSTI-based ART.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , HIV-1 , Humanos , Feminino , Adolescente , Adulto , Infecções por HIV/tratamento farmacológico , Projetos Piloto , Emtricitabina/uso terapêutico , Estudos Transversais , Inibidores de Integrase de HIV/uso terapêutico
2.
HIV Med ; 23(4): 324-330, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35193172

RESUMO

INTRODUCTION: This study aimed to characterize and identify factors associated with HIV care among transgender (trans) women living with HIV (TWLWH) in two urban centres in Canada. METHODS: Retrospective data were collected from clinic charts of TWLWH aged 16 years and older across seven family medicine, endocrinology and/or HIV clinics in Montreal and Toronto, Canada, from 2018 to 2019 (n = 86). We assessed the proportion of individuals being ever engaged in HIV care [defined as having any recorded antiretroviral therapy (ART) regimen and/or viral load], current ART use, and most recent viral load (suppressed [<200 copies/ml] vs. unsuppressed) overall and compared across subgroups using χ2 tests. RESULTS: All TWLWH in our sample [100.0%, 95% confidence interval (CI): 95.8-100.0%] were engaged in HIV care; most (93.0%, 95% CI: 85.4-97.4%) were currently using ART and most (93.4%, 95% CI: 85.3-97.8%) with complete data (n = 71/76) were virally suppressed. A higher proportion of trans women of colour (100.0%) reported current ART use compared with white trans women (76.9%, p = 0.017). A higher proportion of those with no documented history of injection drug use (IDU; 96.6%) were virally suppressed compared with those with a history of IDU (66.7%, p = 0.022). Although not statistically significant, 96.2% of those currently reporting feminizing hormone use were virally suppressed, compared with 85.0% of those not reporting use (p = 0.202). CONCLUSIONS: Once engaged in HIV care, TWLWH in Canada appear to have excellent ART use and viral suppression. Findings can be leveraged to identify target populations to enhance HIV care and to further explore the relationship between gender-affirming medical care and HIV care.


Assuntos
Infecções por HIV , Pessoas Transgênero , Adolescente , Canadá/epidemiologia , Feminino , Humanos , Estudos Retrospectivos , Carga Viral
4.
Antimicrob Agents Chemother ; 59(4): 2113-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25624332

RESUMO

Staphylococcus aureus is a virulent pathogen that is responsible for a wide range of superficial and invasive infections. Its resistance to existing antimicrobial drugs is a global problem, and the development of novel antimicrobial agents is crucial. Antimicrobial peptides from natural resources offer potential as new treatments against staphylococcal infections. In the current study, we have examined the antimicrobial properties of peptides isolated from anuran skin secretions and cyclized synthetic analogues of these peptides. The structures of the peptides were elucidated by nuclear magnetic resonance (NMR) spectroscopy, revealing high structural and sequence similarity with each other and with sunflower trypsin inhibitor 1 (SFTI-1). SFTI-1 is an ultrastable cyclic peptide isolated from sunflower seeds that has subnanomolar trypsin inhibitory activity, and this scaffold offers pharmaceutically relevant characteristics. The five anuran peptides were nonhemolytic and noncytotoxic and had trypsin inhibitory activities similar to that of SFTI-1. They demonstrated weak in vitro inhibitory activities against S. aureus, but several had strong antibacterial activities against S. aureus in an in vivo murine wound infection model. pYR, an immunomodulatory peptide from Rana sevosa, was the most potent, with complete bacterial clearance at 3 mg · kg(-1). Cyclization of the peptides improved their stability but was associated with a concomitant decrease in antimicrobial activity. In summary, these anuran peptides are promising as novel therapeutic agents for treating infections from a clinically resistant pathogen.


Assuntos
Antibacterianos/uso terapêutico , Anuros/metabolismo , Peptídeos/uso terapêutico , Dermatopatias Bacterianas/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Inibidores da Tripsina/uso terapêutico , Animais , Antibacterianos/síntese química , Sobrevivência Celular/efeitos dos fármacos , Ciclização , Feminino , Humanos , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Modelos Moleculares , Peptídeos/síntese química , Peptídeos/química , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Dermatopatias Bacterianas/microbiologia , Infecções Estafilocócicas/microbiologia , Inibidores da Tripsina/síntese química , Inibidores da Tripsina/química
5.
Med J Malaysia ; 66(5): 497-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22390110

RESUMO

We present a rare case of Tay-Sachs disease with retinal 'cherry-red spots' in a 19-month-old Malay child. Molecular genetic studies confirmed the diagnosis. The case highlights that 'cherry-red spot' is a useful clinical clue in Tay-Sachs disease and several other lysosomal storage disorders. It serves as an ideal illustration of the eye as a window to inborn error of metabolism.


Assuntos
Doenças Retinianas/patologia , Doença de Tay-Sachs/patologia , Hexosaminidase A/genética , Humanos , Lactente , Malásia , Masculino , Doenças Retinianas/genética , Doença de Tay-Sachs/genética
6.
Br J Surg ; 96(11): 1323-35, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19847872

RESUMO

BACKGROUND: Postoperative intra-abdominal adhesion is associated with high morbidity and mortality. Smad7, a protein that occupies a strategic position in fibrogenesis, inhibits the transforming growth factor (TGF) beta/Smad signalling pathway. In this study the therapeutic potential of exogenous Smad7 in preventing fibrogenesis in postoperative intra-abdominal adhesion was investigated. METHODS: Intra-abdominal adhesion was induced in a rodent model by peritoneal abrasion. Smad7 was delivered into the peritoneal cavity by a non-viral ultrasound-microbubble-mediated naked gene transfection system. The effect of Smad7 transgene on adhesion formation was studied by measuring changes in TGF-beta, fibrogenic factors, alpha-SMA and Smad2/3 activation in the anterior abdominal wall. RESULTS: Four weeks after surgical abrasion, all rats developed significant peritoneal adhesion with enhanced TGF-beta expression, increased levels of extracellular matrix components and activated myofibroblasts, accompanied by decreased Smad7 expression and increased Smad2/3 activation. In rats treated with the Smad7 transgene, the incidence and severity of peritoneal adhesion were significantly reduced, with biochemical downregulation of fibrogenic factors and inhibition of Smad2/3 activation. Serial quantitation using magnetic resonance imaging revealed a significant reduction in adhesion areas from day 14 onwards. CONCLUSION: Ultrasound-microbubble-mediated gene transfection provides timely targeted gene delivery for the treatment of postoperative peritoneal adhesions.


Assuntos
Técnicas de Transferência de Genes , Vetores Genéticos/fisiologia , Doenças Peritoneais/prevenção & controle , Proteína Smad7/administração & dosagem , Aderências Teciduais/prevenção & controle , Transgenes/fisiologia , Parede Abdominal , Animais , Matriz Extracelular/patologia , Imuno-Histoquímica , Masculino , Microbolhas , Doenças Peritoneais/metabolismo , Doenças Peritoneais/patologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Proteína Smad7/genética , Aderências Teciduais/metabolismo , Aderências Teciduais/patologia , Fator de Crescimento Transformador beta/biossíntese , Regulação para Cima
7.
Oxid Med Cell Longev ; 2019: 1486232, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467629

RESUMO

Ionizing radiation-induced cardiovascular diseases (CVDs) have been well documented. However, the mechanisms of CVD genesis are still not fully understood. In this study, human umbilical vein endothelial cells (HUVECs) were exposed to gamma irradiation at different doses ranging from 0.2 Gy to 5 Gy. Cell viability, migration ability, permeability, oxidative and nitrosative stresses, inflammation, and nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) pathway activation were evaluated postirradiation. It was found that gamma irradiation at doses ranging from 0.5 Gy to 5 Gy inhibited the migration ability of HUVECs without any significant effects on cell viability at 6 h and 24 h postirradiation. The decreased transendothelial electrical resistance (TEER), increased permeability, and disruption of cellular junctions were observed in HUVECs after gamma irradiation accompanied by the lower levels of junction-related proteins such as ZO-1, occludin, vascular endothelial- (VE-) cadherin, and connexin 40. The enhanced oxidative and nitrosative stresses, e.g., ROS and NO2 - levels and inflammatory cytokines IL-6 and TNF-α were demonstrated in HUVECs after gamma irradiation. Western blot results showed that protein levels of mitogen-activated protein kinase (MAPK) pathway molecules p38, p53, p21, and p27 increased after gamma irradiation, which further induced the activation of the NF-κB pathway. BAY 11-7085, an inhibitor of NF-κB activation, was demonstrated to partially block the effects of gamma radiation in HUVECs examined by TEER and FITC-dextran permeability assay. We therefore concluded that the gamma irradiation-induced disruption of cellular junctions in HUVECs was through the inflammatory MAPK/NF-κB signaling pathway.


Assuntos
Raios gama/efeitos adversos , Células Endoteliais da Veia Umbilical Humana/efeitos da radiação , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Humanos
8.
Leukemia ; 21(7): 1423-30, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17476279

RESUMO

Aldehyde dehydrogenase (ALDH) activity is used to define normal hematopoietic stem cell (HSC), but its link to leukemic stem cells (LSC) in acute myeloid leukemia (AML) is currently unknown. We hypothesize that ALDH activity in AML might be correlated with the presence of LSC. Fifty-eight bone marrow (BM) samples were collected from AML (n=43), acute lymphoblastic leukemia (ALL) (n=8) and normal cases (n=7). In 14 AML cases, a high SSC(lo)ALDH(br) cell population was identified (ALDH(+)AML) (median: 14.89%, range: 5.65-48.01%), with the majority of the SSC(lo)ALDH(br) cells coexpressing CD34(+). In another 29 cases, there was undetectable (n=23) or rare (< or =5%) (n=6) SSC(lo)ALDH(br) population (ALDH(-)AML). Among other clinicopathologic variables, ALDH(+)AML was significantly associated with adverse cytogenetic abnormalities. CD34(+) BM cells from ALDH(+)AML engrafted significantly better in NOD/SCID mice (ALDH(+)AML: injected bone 21.11+/-9.07%; uninjected bone 1.52+/-0.75% vs ALDH(-)AML: injected bone 1.77+/-1.66% (P=0.05); uninjected bone 0.23+/-0.23% (P=0.03)) with the engrafting cells showing molecular and cytogenetic aberrations identical to the original clones. Normal BM contained a small SSC(lo)ALDH(br) population (median: 2.92%, range: 0.92-5.79%), but none of the ALL cases showed this fraction. In conclusion, SSC(lo)ALDH(br) cells in ALDH(+)AML might denote primitive LSC and confer an inferior prognosis in patients.


Assuntos
Aldeído Desidrogenase/análise , Leucemia Mieloide/patologia , Transplante de Neoplasias , Células-Tronco Neoplásicas/patologia , Doença Aguda , Adulto , Idoso , Animais , Antígenos CD34/análise , Exame de Medula Óssea , Estudos de Casos e Controles , Feminino , Humanos , Leucemia Mieloide/diagnóstico , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Prognóstico
9.
Nat Commun ; 9(1): 2411, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925835

RESUMO

Asparaginyl endopeptidases (AEPs) are proteases that have crucial roles in plant defense and seed storage protein maturation. Select plant AEPs, however, do not function as proteases but as transpeptidases (ligases) catalyzing the intra-molecular ligation of peptide termini, which leads to peptide cyclization. These ligase-type AEPs have potential biotechnological applications ranging from in vitro peptide engineering to plant molecular farming, but the structural features enabling these enzymes to catalyze peptide ligation/cyclization rather than proteolysis are currently unknown. Here, we compare the sequences, structures, and functions of diverse plant AEPs by combining molecular modeling, sequence space analysis, and functional testing in planta. We find that changes within the substrate-binding pocket and an adjacent loop, here named the "marker of ligase activity", together play a key role for AEP ligase efficiency. Identification of these structural determinants may facilitate the discovery of more ligase-type AEPs and the engineering of AEPs with tailored catalytic properties.


Assuntos
Cisteína Endopeptidases/metabolismo , Peptídeos Cíclicos/biossíntese , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Cisteína Endopeptidases/genética , Modelos Moleculares , Proteínas de Plantas/genética , Plantas/genética , Plantas Geneticamente Modificadas , RNA de Plantas/genética , Análise de Sequência de RNA
10.
Int J Mol Med ; 17(6): 1151-5, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16685429

RESUMO

Musculoskeletal allotransplantion is the most common form of human tissue transplantation. Unlike solid organ transplants, bone allotransplants undergo rigorous processing and are considered non-viable tissue. In this study, we propose that donor genetic material may exist in circulation after bone allotransplantation. Fifty-one female patients who received bone allotransplants from male donors were assessed. Blood plasma samples were analyzed using real-time quantitative polymerase chain reaction (PCR) with dual labeled fluorogenic probes for the presence of the SRY gene on the Y chromosome. Of the total 51 patients, the SRY sequence was detected in 6 patients. Five were positive at day 1 postoperatively and negative thereafter, with the remaining patient positive at 3 months post-transplantation. Our results document, for the first time, the presence of donor DNA in the circulation of recipients after bone allotransplantation. Our findings suggest a potential new investigative tool to assess the postoperative status of bone allotransplants.


Assuntos
Remodelação Óssea/genética , Transplante Ósseo , DNA/sangue , Doadores de Tecidos , Cromossomos Humanos Y/genética , Feminino , Genes sry/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Transplante Homólogo
11.
Asia Pac J Public Health ; 18(1): 69-71, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16629441

RESUMO

The prognosis of lung cancer remains poor with overall five year survival figures varying between five and 10% worldwide, However, it has been shown that surgery in patients with early stage disease in non-small cell lung cancer can achieve five year survival rates up to 80%, suggesting that early or delay diagnosis can influence prognosis. Nevertheless, studies addressing this have been inconclusive and mostly derived from Western countries.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirurgia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Prognóstico
12.
Cancer Res ; 60(24): 6878-81, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11156384

RESUMO

We investigated the prognostic implication of pretreatment plasma/serum EBV DNA concentration, as measured by real-time quantitative PCR, in nasopharyngeal carcinoma (NPC). In 91 prospectively recruited NPC patients, those with recurrence or metastasis within the first year after treatment had a higher median plasma EBV DNA concentration than those without events (41,756 copies/ml versus 5,807 copies/ml; P < 0.001, Mann-Whitney rank-sum test). In multivariate logistic regression analysis, plasma EBV DNA was an independent prognostic indicator for early clinical events [relative risk = 3.8 (95% confidence interval, 1.6-9.2 for each 10-fold increase in plasma EBV DNA concentration; P = 0.003)]. In a second cohort of 139 NPC patients followed-up for a median period of 2,027 days (interquartile range, 597-2,335 days), serum EBV DNA was found to be a significant variable associated with NPC-related death in multivariate Cox's regression analysis [relative risk = 1.6 (95% confidence interval, 1.1-2.1 for each 10-fold increase in serum EBV DNA concentration; P = 0.007)]. The quantitation of circulating EBV DNA may thus allow improved prognostication of NPC.


Assuntos
Carcinoma/diagnóstico , Carcinoma/genética , DNA/análise , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/genética , Adulto , Carcinoma/sangue , Carcinoma/mortalidade , Feminino , Herpesvirus Humano 4/metabolismo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/mortalidade , Reação em Cadeia da Polimerase , Prognóstico , Fatores de Tempo
13.
Cancer Res ; 60(9): 2351-5, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10811107

RESUMO

We studied the kinetics of circulating EBV DNA in the plasma of nasopharyngeal carcinoma (NPC) patients. Serial weekly sampling of 10 NPC patients revealed a rapid decline in plasma EBV DNA concentration after treatment. In two subjects, an initial rise in the circulating EBV DNA level was observed immediately after treatment initiation. Plasma EBV DNA levels were monitored daily during the first treatment week in a second cohort of five patients, and the results indicated that an initial rise in plasma EBV DNA concentration could be observed in all subjects during the first treatment week. This observation is consistent with the liberation of EBV DNA after therapy-induced cancer cell death. After this initial rise, plasma EBV DNA concentration was found to decay with a median half-life of 3.8 days (interquartile range, 2.4-4.4 days). Kinetic analysis of circulating tumor-derived DNA during treatment may be a powerful tool for evaluating the in vivo response of NPC and other tumors to antineoplastic treatment and may improve our understanding of the biology of plasma nucleic acids.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/virologia , DNA Viral/sangue , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/virologia , Humanos , Cinética , Reação em Cadeia da Polimerase , Radiografia , Fatores de Tempo
14.
Cancer Res ; 59(21): 5452-5, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10554016

RESUMO

Recently, cell-free EBV DNA has been detected in the plasma and serum of patients with nasopharyngeal carcinoma (NPC). We studied the relationship between plasma/serum EBV DNA and tumor recurrence. Using real-time quantitative PCR, the median plasma EBV DNA concentration in 10 patients with tumor recurrence was determined to be 32,350 copies/ml, whereas that in 15 patients in continuous remission for a mean period of 2 years was 0 copy/ml. Longitudinal follow-up of 17 NPC patients revealed 6 individuals with tumor recurrence and 11 patients who remained in remission. Significant elevations in serum EBV DNA, sometimes up to 6 months before detectable clinical deterioration, were observed in the patients who subsequently developed tumor recurrence. Continuously low or undetectable levels of serum EBV DNA were observed in the patients who remained in remission. These results suggest that plasma/serum cell-free EBV DNA may be a valuable tool for the monitoring of NPC patients for the early detection of tumor recurrence.


Assuntos
Carcinoma de Células Escamosas/virologia , DNA Viral/sangue , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/virologia , Neoplasias Ósseas/secundário , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/radioterapia , Estudos de Casos e Controles , Intervalo Livre de Doença , Seguimentos , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/radioterapia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/virologia , Reação em Cadeia da Polimerase/métodos , Prognóstico , Fatores de Tempo
15.
Cancer Res ; 59(6): 1188-91, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10096545

RESUMO

Using real-time quantitative PCR, cell-free EBV DNA was detectable in the plasma of 96% (55 of 57) of nasopharyngeal carcinoma (NPC) patients (median concentration, 21058 copies/ml) and 7% (3 of 43) of controls (median concentration, 0 copies/ml). Advanced-stage NPC patients had higher plasma EBV DNA levels than those with early-stage disease. At 1 month after completion of radiotherapy, plasma EBV DNA was undetectable in 7 of 15 subjects (47%) but remained high in the remaining 8 subjects (53%). Clinical examination revealed that all of the former seven subjects had complete tumor regression, whereas six of the eight latter subjects exhibited evidence of disease persistence or had developed distant metastases. These results suggest that quantitative analysis of plasma EBV DNA may be a useful clinical and research tool in the screening and monitoring of NPC patients.


Assuntos
DNA Viral/sangue , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Nasofaríngeas/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/efeitos da radiação , Humanos , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Reação em Cadeia da Polimerase
16.
Cell Death Dis ; 7: e2155, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27010856

RESUMO

Studies on the role of Wnt/ß-catenin signaling in different forms of kidney disease have yielded discrepant results. Here, we report the biphasic change of renal ß-catenin expression in mice with overload proteinuria in which ß-catenin was upregulated at the early stage (4 weeks after disease induction) but abrogated at the late phase (8 weeks). Acute albuminuria was observed at 1 week after bovine serum albumin injection, followed by partial remission at 4 weeks that coincided with overexpression of renal tubular ß-catenin. Interestingly, a rebound in albuminuria at 8 weeks was accompanied by downregulated tubular ß-catenin expression and heightened tubular apoptosis. In addition, there was an inverse relationship between Dickkopf-3 (Dkk-3) and renal tubular ß-catenin expression at these time points. In vitro, a similar trend in ß-catenin expression was observed in human kidney-2 (HK-2) cells with acute (upregulation) and prolonged (downregulation) exposure to albumin. Induction of a proapoptotic phenotype by albumin was significantly enhanced by silencing ß-catenin in HK-2 cells. Finally, Dkk-3 expression and secretion was increased after prolonged exposure to albumin, leading to the suppression of intracellular ß-catenin signaling pathway. The effect of Dkk-3 on ß-catenin signaling was confirmed by incubation with exogenous Dkk-3 in HK-2 cells. Taken together, these data suggest that downregulation of tubular ß-catenin signaling induced by Dkk-3 has a detrimental role in chronic proteinuria, partially through the increase in apoptosis.


Assuntos
Apoptose , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Nefropatias/metabolismo , Túbulos Renais/metabolismo , Proteinúria/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Linhagem Celular , Quimiocinas , Regulação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Nefropatias/genética , Nefropatias/patologia , Túbulos Renais/patologia , Camundongos , Proteinúria/genética , Proteinúria/patologia , beta Catenina/genética
17.
Oncogene ; 18(3): 833-6, 1999 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-9989836

RESUMO

Basal-cell carcinomas (BCCs) are the most common cancer in Caucasians. It has been reported that the patched gene is inactivated in 30-40% sporadic BCCs and 20% sporadic medulloblastomas via loss of heterozygosity and nonsense mutations. Recently, two activating smoothened mutations have been found in the sporadic basal cell carcinomas. One, at base pair 1604 (G-to-T transversion) of exon 9, changes codon 535 from tryptophan to leucine, and the other, at base pair 1685 (G-to-A transition) of exon 10, changes codon 562 from arginine to glutamine (Xie et al., 1998). In our study, 1604G-->T was found in 20 out of 97 (20.6%) sporadic BCCs. The high prevalence indicates that 1604G is the mutation hot spot in our tumor samples. This mutation was detected in all three histological subtypes of BCCs, suggesting that smoothened mutation is an early event during the development of the tumor. Our finding of a high smoothened mutation rate, together with high frequent patched gene mutations reported recently, indicates that activation of the hedgehog signal transduction pathway is the most common and early event in the development of sporadic BCCs. Additionally, to determine whether smoothened, like patched, is also involved in the carcinogenesis of medulloblastomas, we screened medulloblastoma samples for these two mutations by restriction analysis. We have found the 1604G-->T mutation in 1 out of 21 medulloblastomas. This result confirmed smoothened gene involvement in the carcinogenesis of medulloblastoma.


Assuntos
Carcinoma Basocelular/genética , Mutação Puntual , Receptores de Superfície Celular/genética , Receptores Acoplados a Proteínas G , Humanos , Receptor Smoothened
18.
Clin Cancer Res ; 7(7): 1856-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11448896

RESUMO

PURPOSE: We investigated the detectability of EBV DNA in the serum of gastric carcinoma patients in Hong Kong. Previous data have shown that approximately 10% of gastric carcinomas in Hong Kong are associated with EBV. EXPERIMENTAL DESIGN: We recruited 51 patients with gastric carcinoma, 30 patients with gastritis, and 197 apparently healthy controls. For gastric carcinoma patients, blood samples were obtained before surgery. After surgery, the resected tumor samples from the cancer cases were subjected to in situ hybridization for small EBV-encoded RNA (EBER). Serum EBV DNA in all cases was measured by real-time quantitative PCR. RESULTS: Serum EBV DNA was detectable in 5 of 5 (100%) EBER-positive gastric carcinoma cases (median concentration, 1063 copies/ml), in 13 of 14 (93%) EBER-negative gastric carcinoma cases with EBER-positive infiltrating lymphocytes (median concentration, 50 copies/ml), and in 0 of 32 (0%) EBER-negative cases. In the nontumor controls, serum EBV DNA was detectable in 7 of 30 (23%) gastritis cases (median concentration, 0 copies/ml) and in 7 of 197 (3.6%) apparently healthy individuals (median concentration, 0 copy/ml). CONCLUSIONS: Our data indicate that serum EBV DNA reflects tumoral EBER status and opens up the possibility that circulating EBV DNA may be used as a tumor marker for the EBER-positive gastric carcinomas. The biological and clinical significance of the presence of low levels of circulating EBV DNA in the minority of gastritis patients and healthy individuals remains to be elucidated.


Assuntos
DNA Viral/sangue , Infecções por Vírus Epstein-Barr/patologia , Herpesvirus Humano 4/genética , Neoplasias Gástricas/patologia , Infecções por Vírus Epstein-Barr/virologia , Gastrite/patologia , Gastrite/virologia , Humanos , Reação em Cadeia da Polimerase , RNA Viral/genética , Neoplasias Gástricas/virologia
19.
Rev Sci Instrum ; 86(8): 083501, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26329186

RESUMO

A grid image refractometer (GIR) has been implemented at the Nike krypton fluoride laser facility of the Naval Research Laboratory. This instrument simultaneously measures propagation angles and transmissions of UV probe rays (λ = 263 nm, Δt = 10 ps) refracted through plasma. We report results of the first Nike-GIR measurement on a CH plasma produced by the Nike laser pulse (∼1 ns FWHM) with the intensity of 1.1 × 10(15) W/cm(2). The measured angles and transmissions were processed to construct spatial profiles of electron density (ne) and temperature (Te) in the underdense coronal region of the plasma. Using an inversion algorithm developed for the strongly refracted rays, the deployed GIR system probed electron densities up to 4 × 10(21) cm(-3) with the density scale length of 120 µm along the plasma symmetry axis. The resulting n(e) and T(e) profiles are verified to be self-consistent with the measured quantities of the refracted probe light.

20.
J Med Chem ; 23(8): 941-5, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7401119

RESUMO

We have determined the molecular structure of the anticancer antiestrogen nafoxidine and compared its three-dimensional structure with two other clinically useful antiestrogens in order to delineate stereochemical parameters in these compounds. Crystals of nafoxidine hydrochloride-ethanol are monoclinic with cell dimensions a = 17.040, b = 7.967, c = 25.260 A, beta = 123.7 degrees, and space group P21/c with four formula units per cell. The structure was solved by direct phasing methods and refined to a discrepancy index of 0.068. The methoxyphenyl and phenyl rings are trans to each other relative to the ethylene bond, and the substituted amine-aryl ether chain has an extended conformation. Stereoscopic superposition drawings and tabular data are given to show structural similarities and difference in nafoxidine, clomiphene, and tamoxifen, the three antiestrogens with with demonstrated clinical efficacy in the management of metastatic mammary carcinoma.


Assuntos
Antineoplásicos , Antagonistas de Estrogênios , Nafoxidina , Pirrolidinas , Fenômenos Químicos , Química , Modelos Moleculares , Conformação Molecular , Difração de Raios X
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