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1.
J Cardiol ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38852775

RESUMO

BACKGROUND: Children with intravenous immunoglobulin (IVIG) resistant Kawasaki disease (KD) are at higher risk of developing coronary artery (CA) aneurysm. Early identification of high-risk patients using a predictive tool would allow for earlier interventions to prevent cardiac complications. METHODS: Children with KD who were admitted to five selected hospitals in Malaysia between 2008 and 2018 and received 2 g/kg of IVIG within 10 days from the onset of illness were included. Predictors of IVIG resistance in KD were determined using multiple logistic regression analysis. An optimal cut-off point was set using receiver operative characteristic curve and a final multiple logistic regression analysis was performed entering these cut-off points. A new scoring system was constructed. RESULTS: A total of 276 patients were included. IVIG resistance occurred in 9.1 % of them. Total bilirubin [OR 7.37; 95 % CI (2.18, 24.83)], male sex [OR 0.34; 95 % CI (0.10, 1.19)], C-reactive protein (CRP) [OR 0.17; 95 % CI (0.02, 1.38)] and neutrophils [OR 0.25; 95 % CI (0.05, 1.21)] were found to be significant predictors for IVIG resistance. The findings led to the development of a new predictive tool called the Hibiscus score, which scored 1 point each for neutrophils ≥60 %, CRP ≥80 mg/L, and male sex, while total bilirubin ≥9.4 µmol/L scored 2 points. A cut-off point of ≥4 with this prediction score yielded a sensitivity of 78.9 % and specificity of 80.5 %, with area under the curve of 0.835 [95 % CI (0.752, 0.919)]. CA aneurysms occurred in 6.7 % of IVIG responders and 32 % of IVIG-resistant children (p < 0.001). CONCLUSION: The findings suggest that the Hibiscus score has a higher predictive power than the existing scoring systems for IVIG resistance in children with KD in Malaysia. However, external validation is required to enable its use to guide treatment decisions.

2.
Orthod Craniofac Res ; 27(1): 84-94, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37452556

RESUMO

OBJECTIVE: Dysregulation of Fibroblast Growth Factor 10 (FGF10), a member of the family of Fibroblast Growth Factor (FGF) proteins, has been implicated in craniofacial and dental anomalies, including craniosynostosis, cleft palate, and Lacrimo-Auriculo-Dento-Digital Syndrome. The aim of this murine study was to assess the craniofacial and dental phenotypes associated with a heterozygous FGF10 gene (FGF10+/- ) mutation at skeletal maturity. METHODS: Skulls of 40 skeletally mature mice, comprising two genotypes (heterozygous FGF10+/- mutation, n = 22; wildtype, n = 18) and two sexes (male, n = 23; female, n = 17), were subjected to micro-computed tomography. Landmark-based linear dimensions were measured for the cranial vault, maxilla, mandible, and first molar teeth. Multivariate analysis of variance was performed to assess whether there were significant differences in the craniofacial and dental structures between genotypes and sexes. RESULTS: The craniomaxillary skeleton and the first molar teeth were smaller in the FGF10+/- mice (P < .05), but the mandible was unaffected. Sex did not have a significant effect on these structures (P > .05). Cranial sutural defects were noted in 5/22 (22.7%) mutant versus 2/18 (11.1%) wildtype mice, and cleft palate in only one (4.5%) mutant mouse. None of the mice displayed craniosynostosis, expansive bony lesions, bifid condyles, or impacted teeth. CONCLUSION: The FGF10+/- mutation was associated with craniomaxillary skeletal hypoplasia that probably arose from deficient (delayed) intramembranous ossification of the sutured bones. Overall, the skeletal and dental data suggest that the FGF10 gene plays an important role in the aetiology of craniofacial dysmorphology and malocclusion.


Assuntos
Fissura Palatina , Anormalidades Craniofaciais , Craniossinostoses , Camundongos , Masculino , Feminino , Animais , Fissura Palatina/genética , Microtomografia por Raio-X , Fator 10 de Crescimento de Fibroblastos/genética , Modelos Animais de Doenças , Anormalidades Craniofaciais/diagnóstico por imagem , Anormalidades Craniofaciais/genética , Craniossinostoses/genética , Mutação/genética
3.
Int J Paediatr Dent ; 33(6): 543-552, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36826376

RESUMO

BACKGROUND: Molar-root incisor malformation (MRIM) is a rare dental anomaly featuring constricted cervical margins and tapered, narrow root and pulp morphology, often associated with severe toothache and infection. AIM: The aim of this study was to determine the prevalence of MRIM in children seen in a specialist paediatric dental unit of a tertiary referral hospital and to describe the characteristics of affected individuals. DESIGN: This study was an audit of children attending from November 2020 to November 2021. Radiographs were used to identify individuals with MRIM, and clinical data were collated. In addition, histology and microcomputed tomography (microCT) imaging were performed on teeth extracted from an affected individual. RESULTS: The prevalence of MRIM was five cases of 1054 children examined (0.47% or 1:210). The permanent first molars were affected in all five children and the primary second molars in two children; all children had medical comorbidities and multiple exposures to general anesthesia before 4 years of age. In addition, histological and microCT analyses displayed numerous microchannels connecting the pulp chamber to the external surface of the tooth at the furcation. CONCLUSIONS: Molar-root incisor malformation is an uncommon dental anomaly affecting paediatric patients with multiple comorbidities and is characterized by porosities extending from the pulp chamber to the external tooth surface, predisposing the risk of bacterial ingress from the oral cavity into the pulp chamber. Early detection may prevent atypical odontogenic facial pain and infection.


Assuntos
Incisivo , Anormalidades Dentárias , Humanos , Criança , Incisivo/diagnóstico por imagem , Prevalência , Microtomografia por Raio-X , Anormalidades Dentárias/diagnóstico por imagem , Anormalidades Dentárias/epidemiologia , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
5.
Hum Vaccin Immunother ; 18(6): 2124781, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36269944

RESUMO

To evaluate the early vaccine landscape relative to challenges faced by low- and middle-income countries (LMIC), we conducted a cross-sectional study of all COVID-19 vaccines in clinical trials in 2021 (n = 123) using a structured 13-point analytic framework. Supply sustainability was defined as a composite metric of four manufacturing and regulation variables. Vaccine desirability was defined as a composite metric of nine development and distribution variables. Ten vaccines in phases 2/3, 3, or 4 and five vaccines in phases 1 and 1/2 had a sustainability score equal to or above 0.5. Ten vaccines in phases 2/3, 3, or 4 and seven vaccines in phases 1 and 1/2 had a desirability score equal to or above 0.5. No vaccines in Phases 2/3, 3, or 4 met more than one distribution criterion. Structured assessment COVID-19 vaccine candidates in clinical trials in 2021 revealed numerous challenges to adequate access in LMICs. Key policy recommendations included increasing technology transfer to LMICs, developing international legal mechanisms to prevent export bans, and increasing investment in vaccine candidates with more favorable distribution profiles.


Assuntos
COVID-19 , Vacinas , Humanos , Vacinas contra COVID-19 , Países em Desenvolvimento , Estudos Transversais , COVID-19/prevenção & controle
6.
J Am Anim Hosp Assoc ; 58(2): 91-95, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35195709

RESUMO

A feral, domestic shorthair was evaluated for palliative treatment of a pulmonary mass with secondary pneumonia. Because of the patient's temperament and extent of the mass, tracheobronchoscopy, bronchial stenting, and biopsy were elected, followed by adjuvant radiation therapy. Stent placement across the malignantly obstructed bronchus permitted drainage and recruitment of the infected lung lobe. Uncomplicated radiation therapy, stent extension, and debulking due to tissue ingrowth were subsequently performed. Successful palliation was achieved for 323 days with subsequent progressive pulmonary and liver metastases.


Assuntos
Obstrução das Vias Respiratórias , Carcinoma , Doenças do Gato , Cuidados Paliativos , Stents , Obstrução das Vias Respiratórias/cirurgia , Obstrução das Vias Respiratórias/veterinária , Animais , Brônquios/cirurgia , Carcinoma/veterinária , Doenças do Gato/cirurgia , Gatos , Stents/veterinária , Resultado do Tratamento
7.
Methods Mol Biol ; 2403: 107-127, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34913120

RESUMO

Craniofacial phenomics has opened up numerous opportunities to correlate genetic and epigenetic factors to craniofacial phenotypes in order to improve our understanding of growth and development in health and disease. Three-dimensional (3D) imaging has played a key role in advancing craniofacial phenomics by facilitating highly sensitive and specific characterizations of craniofacial and dental morphology. Here we describe the use of micro-computed tomography (micro-CT) to image the murine craniofacial complex, followed by surface reconstruction for traditional morphometric analyses. We also describe the application of geometric morphometrics, based on Generalized Procrustes Analysis, for use in human premolars. These principles are interchangeable between various vertebrate species, and between various surface imaging techniques (including micro-CT and 3D surface scanners), offering a high level of versatility and precision for extensive phenotyping of the entire craniofacial complex.


Assuntos
Fenômica , Crânio , Animais , Humanos , Imageamento Tridimensional , Camundongos , Fenótipo , Crânio/diagnóstico por imagem , Microtomografia por Raio-X
8.
Methods Mol Biol ; 2403: 129-145, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34913121

RESUMO

X-ray micro-computed tomography (micro-CT) imaging has important applications in microarchitecture analysis of cortical and trabecular bone structure. While standardized protocols exist for micro-CT-based microarchitecture assessment of long bones, specific protocols need to be developed for different types of skull bones taking into account differences in embryogenesis, organization, development, and growth compared to the rest of the body. This chapter describes the general principles of bone microarchitecture analysis of murine craniofacial skeleton to accommodate for morphological variations in different regions of interest.


Assuntos
Crânio , Animais , Densidade Óssea , Osso Esponjoso , Cabeça , Camundongos , Crânio/diagnóstico por imagem , Microtomografia por Raio-X
9.
J Affect Disord ; 281: 384-389, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33352408

RESUMO

Major depressive disorder is associated with pro-inflammatory markers, such as cytokines TNF-alpha, IL-6, IL-1ß, and C-reactive protein. Galectin-3 is a novel emerging biomarker with pro-inflammatory properties. It is a saccharide binding protein distributed throughout many tissues with varying functions and is a predictor of poor outcomes in patients with heart failure and stroke. However, its role as a predictor in depressive symptom severity remains undefined. Data from the community-based Dallas Heart Study (n = 2554) were examined using a multiple linear regression analysis to evaluate the relationship between galectin-3 and depressive symptom severity as assessed with Quick Inventory of Depressive Symptomatology Self-Report (QIDS-SR) scores. Additional covariates included age, sex, race/ethnicity, body mass index (BMI), years of education, serum creatinine, history of diabetes, and smoking history. Galectin-3 levels statistically significantly predicted QIDS-SR depressive symptom severity (ß = 0.055, p = .015). Female sex, smoking status, and BMI were found to be statistically significant positive predictors of depression severity, while age, years of education, non-Hispanic White race, and Hispanic ethnicity were negative predictors of depressive symptom severity. In this large sample, higher galectin-3 levels were associated with higher levels of depressive symptoms. The findings suggest that galectin-3 may be a new and useful inflammatory biomarker associated with depression.


Assuntos
Transtorno Depressivo Maior , Biomarcadores , Depressão/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Feminino , Galectina 3 , Humanos , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença
10.
Nat Rev Drug Discov ; 19(1): 12, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31907432
11.
Am J Physiol Renal Physiol ; 316(6): F1114-F1123, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30908934

RESUMO

Little is known about the population genetics of water balance. A recent meta-genome-wide association study on plasma sodium concentration identified novel loci of high biological plausibility, yet heritability of the phenotype has never been convincingly shown in European ancestry. The present study linked the Vietnam Era Twin Registry with the Department of Veterans Affairs VistA patient care clinical database. Participants (n = 2,370, 59.6% monozygotic twins and 40.4% dizygotic twins) had a median of seven (interquartile range: 3-14) plasma sodium determinations between October 1999 and March 2017. Heritability of the mean plasma sodium concentration among all twins was 0.41 (95% confidence interval: 0.35-0.46) and 0.49 (95% confidence interval: 0.43-0.54) after exclusion of 514 twins with only a single plasma sodium determination. Heritability among Caucasian (n = 1,958) and African-American (n = 268) twins was 0.41 (95% confidence interval: 0.34-0.47) and 0.36 (95% confidence interval: 0.17-0.52), respectively. Exclusion of data from twins who had been prescribed medications known to impact systemic water balance had no effect. The ability of the present study to newly detect substantial heritability across multiple racial groups was potentially a function of the cohort size and relatedness, exclusion of sodium determinations confounded by elevated plasma glucose and/or reduced glomerular filtration rate, transformation of plasma sodium for the independent osmotic effect of plasma glucose, and use of multiple laboratory determinations per individual over a period of years. Individual-level plasma sodium concentration exhibited longitudinal stability (i.e., individuality); the degree to which individual-level means differed from the population mean was substantial, irrespective of the number of determinations. In aggregate, these data establish the heritability of plasma sodium concentration in European ancestry and corroborate its individuality.


Assuntos
Heterogeneidade Genética , Hereditariedade , Sódio/sangue , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Veteranos , Equilíbrio Hidroeletrolítico/genética , Negro ou Afro-Americano/genética , Variação Biológica Individual , Bases de Dados Factuais , Genética Populacional , Taxa de Filtração Glomerular/genética , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estados Unidos , População Branca/genética
12.
BMC Health Serv Res ; 18(1): 5, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29304787

RESUMO

BACKGROUND: Patients with prolonged length of hospital stay (LOS) not only increase their risks of nosocomial infections but also deny other patients access to inpatient care. Hepatobiliary (HPB) malignancies have some of highest incidences in East and Southeast Asia and the management of patients undergoing HPB surgeries have yet to be standardized. With improved neurosurgery techniques for intracranial aneurysms and tumors, neurosurgeries (NS) can be expected to increase. Elective surgeries account for far more operations than emergencies surgeries. Thus, with potentially increased numbers of elective HPB and NS, this study seeks to explore perioperative factors associated with prolonged LOS for these patients to improve safety and quality of practice. METHODS: A retrospective cross-sectional medical record review study from January 2014 to January 2015 was conducted at a 1250-bed tertiary academic hospital in Singapore. All elective HPB and NS patients over 18 years old were included in the study except day and emergency surgeries, resulting in 150 and 166 patients respectively. Prolonged LOS was defined as above median LOS based on the complexity of the surgical procedure. The predictor variables were preoperative, intraoperative, and postoperative factors. Student's t-test and stepwise logistic regression analyses were conducted to determine which factors were associated with prolonged LOS. RESULTS: Factors associated with prolonged LOS for the HPB sample were age and admission after 5 pm but for the NS sample, they were functional status, referral to occupational therapy, and the number of hospital-acquired infections. CONCLUSION: Our findings indicate that preoperative factors had the greatest association with prolonged LOS for HPB and NS elective surgeries even after adjusting for surgical complexity, suggesting that patient safety and quality of care may be improved with better pre-surgery patient preparation and admission practices.


Assuntos
Procedimentos Cirúrgicos do Sistema Biliar , Procedimentos Cirúrgicos Eletivos/normas , Hepatectomia , Tempo de Internação/estatística & dados numéricos , Procedimentos Neurocirúrgicos , Cuidados Pré-Operatórios/normas , Melhoria de Qualidade/organização & administração , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Singapura
13.
Bioorg Med Chem Lett ; 27(3): 632-635, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28025004

RESUMO

Reactive metabolites have been putatively linked to many adverse drug reactions including idiosyncratic toxicities for a number of drugs with black box warnings or withdrawn from the market. Therefore, it is desirable to minimize the risk of reactive metabolite formation for lead molecules in optimization, in particular for non-life threatening chronic disease, to maximize benefit to risk ratio. This article describes our effort in addressing reactive metabolite issues for a series of 3-amino-2-pyridone inhibitors of BTK, e.g. compound 1 has a value of 459pmol/mg protein in the microsomal covalent binding assay. Parallel approaches were taken to successfully resolve the issues: establishment of a predictive screening assay with correlation association of covalent binding assay, identification of the origin of reactive metabolite formation using MS/MS analysis of HLM as well as isolation and characterization of GSH adducts. This ultimately led to the discovery of compound 7 (RN941) with significantly reduced covalent binding of 26pmol/mg protein.


Assuntos
Inibidores de Proteínas Quinases/química , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridonas/química , Tirosina Quinase da Agamaglobulinemia , Glutationa/química , Espectroscopia de Ressonância Magnética , Microssomos/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Piridonas/metabolismo , Espectrometria de Massas em Tandem
14.
Mol Cancer Ther ; 10(12): 2298-308, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21926191

RESUMO

The signaling pathway of the receptor tyrosine kinase MET and its ligand hepatocyte growth factor (HGF) is important for cell growth, survival, and motility and is functionally linked to the signaling pathway of VEGF, which is widely recognized as a key effector in angiogenesis and cancer progression. Dysregulation of the MET/VEGF axis is found in a number of human malignancies and has been associated with tumorigenesis. Cabozantinib (XL184) is a small-molecule kinase inhibitor with potent activity toward MET and VEGF receptor 2 (VEGFR2), as well as a number of other receptor tyrosine kinases that have also been implicated in tumor pathobiology, including RET, KIT, AXL, and FLT3. Treatment with cabozantinib inhibited MET and VEGFR2 phosphorylation in vitro and in tumor models in vivo and led to significant reductions in cell invasion in vitro. In mouse models, cabozantinib dramatically altered tumor pathology, resulting in decreased tumor and endothelial cell proliferation coupled with increased apoptosis and dose-dependent inhibition of tumor growth in breast, lung, and glioma tumor models. Importantly, treatment with cabozantinib did not increase lung tumor burden in an experimental model of metastasis, which has been observed with inhibitors of VEGF signaling that do not target MET. Collectively, these data suggest that cabozantinib is a promising agent for inhibiting tumor angiogenesis and metastasis in cancers with dysregulated MET and VEGFR signaling.


Assuntos
Anilidas/uso terapêutico , Processos de Crescimento Celular/efeitos dos fármacos , Metástase Neoplásica/prevenção & controle , Neoplasias/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Piridinas/uso terapêutico , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Anilidas/farmacologia , Animais , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Camundongos , Camundongos Nus , Modelos Biológicos , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Piridinas/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
15.
Bioorg Med Chem Lett ; 21(7): 1933-6, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21388809

RESUMO

The highly potent but modestly selective N-(2-amino-4-methoxy-benzothiazol-7-yl)-N-ethyl-acetamide derivative 2 was selected as the starting point for the design of novel selective A(2B) antagonists, due to its excellent potency, and good drug-like properties. A series of compounds containing nonaromatic amides or ureas of five- or six-membered rings, and also bearing an m-trifluoromethyl-phenyl group (shown to impart superior potency) was prepared and evaluated for their selectivity against the A(2A) and A(1) receptors. This work resulted in the identification of compound 30, with excellent potency and high selectivity against both A(2A) and A(1) receptors.


Assuntos
Antagonistas do Receptor A2 de Adenosina/química , Antagonistas do Receptor A2 de Adenosina/farmacologia , Benzotiazóis/farmacologia , Descoberta de Drogas , Benzotiazóis/química , Relação Estrutura-Atividade
16.
J Med Chem ; 54(7): 2433-46, 2011 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-21413799

RESUMO

Diacylglycerol acyltransferase-1 (DGAT-1) is the enzyme that catalyzes the final and committed step of triglyceride formation, namely, the acylation of diacylglycerol with acyl coenzyme A. DGAT-1 deficient mice demonstrate resistance to weight gain on high fat diet, improved insulin sensitivity, and reduced liver triglyceride content. Inhibition of DGAT-1 thus represents a potential novel approach for the treatment of obesity, dyslipidemia, and metabolic syndrome. In this communication, we report the identification of the lead structure 6 and our lead optimization efforts culminating in the discovery of potent, selective, and orally efficacious carboxylic acid derivatives of 2-phenyl-5-trifluoromethyloxazole-4-carboxamides. In particular, compound 29 (DGAT-1 enzyme assay, IC(50) = 57 nM; CHO-K1 cell triglyceride formation assay, EC(50) = 0.5 µM) demonstrated dose dependent inhibition of weight gain in diet induced obese (DIO) rats (0.3, 1, and 3 mg/kg, p.o., qd) during a 21-day efficacy study. Furthermore, compound 29 demonstrated improved glucose tolerance determined by an oral glucose tolerance test (OGTT).


Assuntos
Amidas/química , Amidas/farmacologia , Ácidos Carboxílicos/química , Diabetes Mellitus/tratamento farmacológico , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Descoberta de Drogas , Obesidade/tratamento farmacológico , Oxazóis/química , Oxazóis/farmacologia , Administração Oral , Amidas/administração & dosagem , Amidas/farmacocinética , Animais , Linhagem Celular , Diabetes Mellitus/enzimologia , Cães , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Obesidade/enzimologia , Oxazóis/administração & dosagem , Oxazóis/farmacocinética , Ratos
17.
Bioorg Med Chem Lett ; 20(14): 4140-6, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20541935

RESUMO

7-N-Acetamide-4-methoxy-2-aminobenzothiazole 4-fluorobenzamide (compound 1) was chosen as a drug-like and non-xanthine based starting point for the discovery of A(2B) receptor antagonists because of its slight selectivity against A(1) and A(2A) receptors and modest A(2B) potency. SAR exploration of compound 1 described herein included modifications to the 7-N-acetamide group, substitution of the 4-methoxy group by halogens as well as replacement of the p-flouro-benzamide side chain. This work culminated in the identification of compound 37 with excellent A(2B) potency, modest selectivity versus A(2A) and A(1) receptors, and good rodent PK properties.


Assuntos
Antagonistas do Receptor A2 de Adenosina/farmacologia , Benzotiazóis/farmacologia , Receptor A2B de Adenosina/metabolismo , Xantina/química , Antagonistas do Receptor A2 de Adenosina/química , Benzotiazóis/química , Relação Estrutura-Atividade
18.
Cancer Res ; 69(20): 8009-16, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19808973

RESUMO

The Met receptor tyrosine kinase and its ligand, hepatocyte growth factor (HGF), are overexpressed and/or activated in a wide variety of human malignancies. Vascular endothelial growth factor (VEGF) receptors are expressed on the surface of vascular endothelial cells and cooperate with Met to induce tumor invasion and vascularization. EXEL-2880 (XL880, GSK1363089) is a small-molecule kinase inhibitor that targets members of the HGF and VEGF receptor tyrosine kinase families, with additional inhibitory activity toward KIT, Flt-3, platelet-derived growth factor receptor beta, and Tie-2. Binding of EXEL-2880 to Met and VEGF receptor 2 (KDR) is characterized by a very slow off-rate, consistent with X-ray crystallographic data showing that the inhibitor is deeply bound in the Met kinase active site cleft. EXEL-2880 inhibits cellular HGF-induced Met phosphorylation and VEGF-induced extracellular signal-regulated kinase phosphorylation and prevents both HGF-induced responses of tumor cells and HGF/VEGF-induced responses of endothelial cells. In addition, EXEL-2880 prevents anchorage-independent proliferation of tumor cells under both normoxic and hypoxic conditions. In vivo, these effects produce significant dose-dependent inhibition of tumor burden in an experimental model of lung metastasis. Collectively, these data indicate that EXEL-2880 may prevent tumor growth through a direct effect on tumor cell proliferation and by inhibition of invasion and angiogenesis mediated by HGF and VEGF receptors.


Assuntos
Anilidas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Experimentais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Quinolinas/farmacologia , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Derme/citologia , Derme/efeitos dos fármacos , Derme/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fator de Crescimento de Hepatócito/farmacologia , Humanos , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/patologia , Neovascularização Patológica/prevenção & controle , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Veias Umbilicais/citologia , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo
19.
Arch Neurol ; 65(1): 137-41, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18195152

RESUMO

BACKGROUND: Mutations in protein-O-mannose-beta1,2-N-acetylglucosaminyltransferase 1 (POMGnT1) have been found in muscle-eye-brain disease, a congenital muscular dystrophy with structural eye and brain defects and severe mental retardation. OBJECTIVE: To investigate whether mutations in POMGnT1 could be responsible for milder allelic variants of muscular dystrophy. DESIGN: Screening for mutations in POMGnT1. SETTING: Tertiary neuromuscular unit. PATIENT: A patient with limb-girdle muscular dystrophy phenotype, with onset at 12 years of age, severe myopia, normal intellect, and decreased alpha-dystroglycan immunolabeling in skeletal muscle. RESULTS: A homozygous POMGnT1 missense mutation (c.1666G>A, p.Asp556Asn) was identified. Enzyme studies of the patient's fibroblasts showed an altered kinetic profile, less marked than in patients with muscle-eye-brain disease and in keeping with the relatively mild phenotype in our patient. CONCLUSIONS: Our findings widen the spectrum of disorders known to result from mutations in POMGnT1 to include limb-girdle muscular dystrophy with no mental retardation. We propose that this condition be known as LGMD2M. The enzyme assay used to diagnose muscle-eye-brain disease may not detect subtle abnormalities of POMGnT1 function, and additional kinetic studies must be carried out in such cases.


Assuntos
Distrofia Muscular do Cíngulo dos Membros/genética , N-Acetilglucosaminiltransferases/genética , Alelos , Western Blotting , Criança , Análise Mutacional de DNA , Distroglicanas/metabolismo , Fibroblastos/enzimologia , Testes Genéticos , Humanos , Imuno-Histoquímica , Cinética , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Distrofia Muscular do Cíngulo dos Membros/complicações , Distrofia Muscular do Cíngulo dos Membros/psicologia , Mutação , Mutação de Sentido Incorreto/genética , Miopia/etiologia , Fenótipo
20.
Methods Enzymol ; 417: 359-89, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17132514

RESUMO

Caenorhabditis elegans is becoming a popular tool for the study of glycan function particularly as it applies to development. More than 150 C. elegans genes have been identified as homologs of vertebrate genes involved in glycan metabolism. However, only a relatively small number of these genes have been expressed and studied in any detail. Oligomannose N-glycans (Man5-9GlcNAc2Asn), major components of the N-glycans of all eukaryotes including C. elegans, are essential, at least in part, for eukaryote survival, because they play an important role in protein quality control. In addition, vertebrates make hybrid (GlcNAcMan3-5GlcNAc2Asn) and complex (XGlcNAc2-6Man3GlcNAc2Asn) but little or no paucimannose (Man3-4GlcNAc2Asn)N-glycans, whereas plants, insects, and C. elegans make paucimannose but little or no hybrid nor complex N-glycans. UDP-GlcNAc:alpha3-D-mannoside beta1,2-N-acetylglucosaminyltransferase I (encoded by the gene Mgat1) controls the synthesis of hybrid, complex, and paucimannose N-glycans in all eukaryotes. C. elegans has three genes encoding beta1,2-N-acetylglucosaminyltransferase I (gly-12, gly-13, gly-14). To determine the functional requirement for this enzyme in worms, we generated seven worm strains with mutations in these three genes (gly-12, dpy-6 gly-13, gly-14, gly-12 gly-13, gly-14;gly-12, gly-14;dpy-6 gly-13 and gly-14;gly-12 gly-13). Whereas mice and Drosophila melanogaster with null mutations in Mgat1 suffer severe developmental abnormalities, all seven C. elegans strains with null mutations in the genes encoding beta1,2-N-acetylglucosaminyltransferase I develop normally and seem to have a wild-type phenotype. We now present evidence that beta1,2-N-acetylglucosaminyltransferase I-dependent N-glycans (consisting mainly of paucimannose N-glycans) play a role in the interaction of C. elegans with pathogenic bacteria, suggesting that these N-glycans are components of the worm's innate immune system.


Assuntos
Caenorhabditis elegans/imunologia , Caenorhabditis elegans/microbiologia , Nitrogênio/química , Polissacarídeos/fisiologia , Animais , Caenorhabditis elegans/genética , Sequência de Carboidratos , Escherichia coli/imunologia , Imunidade Inata/genética , Dados de Sequência Molecular , Polissacarídeos/química , Pseudomonas aeruginosa/imunologia
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