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1.
Pediatr Surg Int ; 37(11): 1585-1592, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34268609

RESUMO

PURPOSE: To describe the timing of chemotherapy initiation after surgery for Wilms tumor (WT) and neuroblastoma within a dedicated children's cancer center. METHODS: A single-institution retrospective cohort study identified patients that underwent resection of unilateral WT or high-risk neuroblastoma and received adjuvant chemotherapy treatment. Adjuvant chemotherapy initiation and postoperative complications were recorded. RESULTS: Among 47 WT patients, the median time to chemotherapy initiation was 11 days [interquartile range IQR 7-14]. 3 WT patients had post-operative complications, but all preceded chemotherapy. Among 83 patients treated for high-risk neuroblastoma, the median time to chemotherapy was 11 days [IQR 9-14]. High-risk neuroblastoma patients with 30-day postoperative complications had a significantly longer time to initiation of adjuvant chemotherapy (odds ratio 1.13; p = 0.008). Many of these complications preceded and delayed the initiation of post-operative chemotherapy. No complications occurred in the group of 12 (25%) WT patients or 16 (19.3%) neuroblastoma patients who started chemotherapy ≤ 7 days after surgery. CONCLUSION: There is no association between early initiation of adjuvant chemotherapy and post-operative complications including wound healing. Early initiation of chemotherapy (≤ 7 days) is feasible in unilateral WT or high-risk neuroblastoma patients who are otherwise doing well without resulting in a preponderance of wound healing complications.


Assuntos
Neoplasias Renais , Neuroblastoma , Tumor de Wilms , Quimioterapia Adjuvante , Criança , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/cirurgia , Laparotomia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/cirurgia , Estudos Retrospectivos , Tumor de Wilms/tratamento farmacológico , Tumor de Wilms/cirurgia
2.
Nat Commun ; 9(1): 1421, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650949

RESUMO

Acute allergic symptoms are caused by allergen-induced crosslinking of allergen-specific immunoglobulin E (IgE) bound to Fc-epsilon receptors on effector cells. Desensitization with allergen-specific immunotherapy (SIT) has been used for over a century, but the dominant protective mechanism remains unclear. One consistent observation is increased allergen-specific IgG, thought to competitively block allergen binding to IgE. Here we show that the blocking potency of the IgG response to Cat-SIT is heterogeneous. Next, using two potent, pre-selected allergen-blocking monoclonal IgG antibodies against the immunodominant cat allergen Fel d 1, we demonstrate that increasing the IgG/IgE ratio reduces the allergic response in mice and in cat-allergic patients: a single dose of blocking IgG reduces clinical symptoms in response to nasal provocation (ANCOVA, p = 0.0003), with a magnitude observed at day 8 similar to that reported with years of conventional SIT. This study suggests that simply augmenting the blocking IgG/IgE ratio may reverse allergy.


Assuntos
Anticorpos Monoclonais/farmacologia , Dessensibilização Imunológica/métodos , Glicoproteínas/imunologia , Hipersensibilidade/terapia , Imunoglobulina G/farmacologia , Receptores de IgE/imunologia , Adolescente , Adulto , Alérgenos/administração & dosagem , Alérgenos/imunologia , Alérgenos/isolamento & purificação , Pelo Animal/química , Pelo Animal/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Ligação Competitiva , Gatos , Misturas Complexas/química , Misturas Complexas/imunologia , Modelos Animais de Doenças , Feminino , Glicoproteínas/administração & dosagem , Glicoproteínas/isolamento & purificação , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/fisiopatologia , Imunoglobulina E/química , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Imunoglobulina G/biossíntese , Masculino , Camundongos , Pessoa de Meia-Idade , Ligação Proteica/efeitos dos fármacos , Receptores de IgE/química , Receptores de IgE/metabolismo
3.
J Thromb Haemost ; 15(5): 972-982, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28267256

RESUMO

Essentials Vessel stenosis due to large thrombus formation increases local shear 1-2 orders of magnitude. High shear at stenotic sites was exploited to trigger eptifibatide release from nanocapsules. Local delivery of eptifibatide prevented vessel occlusion without increased tail bleeding times. Local nanocapsule delivery of eptifibatide may be safer than systemic antiplatelet therapies. SUMMARY: Background Myocardial infarction and stroke remain the leading causes of mortality and morbidity. The major limitation of current antiplatelet therapy is that the effective concentrations are limited because of bleeding complications. Targeted delivery of antiplatelet drug to sites of thrombosis would overcome these limitations. Objectives Here, we have exploited a key biomechanical feature specific to thrombosis, i.e. significantly increased blood shear stress resulting from a reduction in the lumen of the vessel, to achieve site-directed delivery of the clinically used antiplatelet agent eptifibatide by using shear-sensitive phosphatidylcholine (PC)-based nanocapsules. Methods PC-based nanocapsules (2.8 × 1012 ) with high-dose encapsulated eptifibatide were introduced into microfluidic blood perfusion assays and into in vivo models of thrombosis and tail bleeding. Results Shear-triggered nanocapsule delivery of eptifibatide inhibited in vitro thrombus formation selectively under stenotic and high shear flow conditions above a shear rate of 1000 s-1 while leaving thrombus formation under physiologic shear rates unaffected. Thrombosis was effectively prevented in in vivo models of vessel wall damage. Importantly, mice infused with shear-sensitive antiplatelet nanocapsules did not show prolonged bleeding times. Conclusions Targeted delivery of eptifibatide by shear-sensitive nanocapsules offers site-specific antiplatelet potential, and may form a basis for developing more potent and safer antiplatelet drugs.


Assuntos
Arteriopatias Oclusivas/prevenção & controle , Sistemas de Liberação de Medicamentos/métodos , Fibrinolíticos/administração & dosagem , Nanocápsulas , Peptídeos/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Trombose/prevenção & controle , Animais , Arteriopatias Oclusivas/sangue , Arteriopatias Oclusivas/fisiopatologia , Fenômenos Biomecânicos , Velocidade do Fluxo Sanguíneo , Preparações de Ação Retardada , Modelos Animais de Doenças , Composição de Medicamentos , Eptifibatida , Fibrinolíticos/química , Fibrinolíticos/toxicidade , Hemorragia/induzido quimicamente , Camundongos Endogâmicos C57BL , Peptídeos/química , Peptídeos/toxicidade , Fosfatidilcolinas/química , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/toxicidade , Fluxo Sanguíneo Regional , Estresse Mecânico , Trombose/sangue , Trombose/fisiopatologia
4.
Indian J Cancer ; 52(2): 225-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26853414

RESUMO

BACKGROUND: Survivors of childhood cancer are at increased risk for several cardiometabolic complications. Obesity/overweight and metabolic syndrome have been widely reported in Western literature, but data from India are lacking. AIMS: To perform an objective assessment of nutritional status in a cohort of childhood cancer survivors (CCSs) and to find risk factors for extremes in nutritional status. SETTINGS AND DESIGN: The study was a retrospective chart review of CCSs who attended the late effects clinic of a referral pediatric oncology center over the period of 1 year. MATERIALS AND METHODS: An objective assessment of nutritional status was done, and results were analyzed in two groups: Adult survivors (present age <18 years) and child and adolescent survivors (CASs) (<18 years). The data were then analyzed for possible risk factors. RESULTS: Six hundred and forty-eight survivors were included in the study; of these, 471 were <18 years at follow-up, and 177 were 18 years or older. The prevalence of obesity, overweight, normal, and undernutrition was 2.6%, 10.8%, 62.7%, and 28.8% (CASs) and 0%, 8.5%, 62.7%, and 28.8% (adult survivors), respectively. Factors predictive of overweight/obesity were an initial diagnosis of acute lymphoblastic leukemia, or brain tumor and follow-up duration of >20 years or current age >30 years in adult survivors. CONCLUSIONS: The prevalence of obesity/overweight is lower in our cohort when compared to Western literature. It remains to be clarified whether this reflects the underlying undernutrition in our country, or whether our cohort of survivors is indeed distinct from their Western counterparts. Comparison with age/sex-matched normal controls and baseline parameters would yield more meaningful results.


Assuntos
Neoplasias/epidemiologia , Estado Nutricional , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Masculino , Neoplasias/complicações , Neoplasias/patologia , Obesidade/complicações , Obesidade/patologia , Sobrepeso/complicações , Sobrepeso/patologia , Pediatria , Pobreza , Fatores de Risco
5.
Oncogene ; 34(5): 558-67, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24488013

RESUMO

Diffuse infiltrative invasion is a major cause for the dismal prognosis of glioblastoma multiforme (GBM), but the underlying mechanisms remain incompletely understood. Using human glioma stem cells (GSCs) that recapitulate the invasive propensity of primary GBM, we find that EphA2 critically regulates GBM invasion in vivo. EphA2 was expressed in all seven GSC lines examined, and overexpression of EphA2 enhanced intracranial invasion. The effects required Akt-mediated phosphorylation of EphA2 on serine 897. In vitro the Akt-EphA2 signaling axis is maintained in the absence of ephrin-A ligands and is disrupted upon ligand stimulation. To test whether ephrin-As in tumor microenvironment can regulate GSC invasion, the newly established Efna1;Efna3;Efna4 triple knockout mice (TKO) were used in an ex vivo brain slice invasion assay. We observed significantly increased GSC invasion through the brain slices of TKO mice relative to wild-type (WT) littermates. Mechanistically EphA2 knockdown suppressed stem cell properties of GSCs, causing diminished self-renewal, reduced stem marker expression and decreased tumorigenicity. In a subset of GSCs, the reduced stem cell properties were associated with lower Sox2 expression. Overexpression of EphA2 promoted stem cell properties in a kinase-independent manner and increased Sox2 expression. Disruption of Akt-EphA2 cross-talk attenuated stem cell marker expression and neurosphere formation while having minimal effects on tumorigenesis. Taken together, the results show that EphA2 endows invasiveness of GSCs in vivo in cooperation with Akt and regulates glioma stem cell properties.


Assuntos
Neoplasias Encefálicas/genética , Carcinogênese/genética , Glioblastoma/genética , Proteína Oncogênica v-akt/genética , Receptor EphA2/genética , Animais , Neoplasias Encefálicas/patologia , Regulação Neoplásica da Expressão Gênica , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Knockout , Invasividade Neoplásica/genética , Células-Tronco Neoplásicas/patologia , Proteína Oncogênica v-akt/metabolismo , Fosforilação/genética , Fatores de Transcrição SOXB1/genética , Transdução de Sinais/genética
6.
Eur J Clin Nutr ; 68(12): 1341-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24986819

RESUMO

BACKGROUND/OBJECTIVES: Optimal nutritional status is important in children with cancer, as it can influence clinical outcomes. To improve the nutritional health of children and adolescents receiving treatment for cancer residing in low income and middle-income countries (LMIC), we investigated nutrition practices among these nations' institutions providing treatment for childhood cancer. SUBJECT/METHODS: A cross-sectional survey of nutrition practice was administered to staff members at institutions providing treatment for children with cancer between 2011 and 2012. Countries classified as low income and middle income were divided by geographical region. Final analysis was performed with 96 surveys, which included 27 institutions from Asia, 27 institutions from Latin America and Caribbean, 27 institutions from Africa and 15 institutions from Europe. RESULTS: The study found that 55% of institutions had a dietician available on their service. Access to dieticians, lack of nutrition resources and lack of nutrition education of staff were the main barriers to providing nutrition care in LMIC. Half of the institutions performed nutritional assessment at diagnosis, and the methods used varied widely. Twenty-nine percent of all institutions used complementary and alternate therapies within their clinical practice, and 35% of institutions reported that nutrition education was provided to patients and families. CONCLUSIONS: Priority areas for improving the nutritional management in LMIC include the following: (1) improved nutrition education and assessment tools for doctors and nurses; (2) increased availability of nutrition education resources for families and patients; and (3) identification of the role of complementary and alternative therapies in closing gaps in symptom management in these institutions.


Assuntos
Neoplasias/terapia , Avaliação Nutricional , Estado Nutricional , Adolescente , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Estudos Transversais , Países em Desenvolvimento , Humanos , Inquéritos e Questionários
8.
J Pathol ; 230(1): 95-106, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23299523

RESUMO

Podocytes are crucial for preventing the passage of albumin into the urine and, when lost, are associated with the development of albuminuria, renal failure and cardiovascular disease. Podocytes have limited capacity to regenerate, therefore pro-survival mechanisms are critically important. Insulin-like growth factor-II (IGF-II) is a potent survival and growth factor; however, its major function is thought to be in prenatal development, when circulating levels are high. IGF-II has only previously been reported to continue to be expressed in discrete regions of the brain into adulthood in rodents, with systemic levels being undetectable. Using conditionally immortalized human and ex vivo adult mouse cells of the glomerulus, we demonstrated the podocyte to be the major glomerular source and target of IGF-II; it signals to this cell via the IGF-I receptor via the PI3 kinase and MAPK pathways. Functionally, a reduction in IGF signalling causes podocyte cell death in vitro and glomerular disease in vivo in an aged IGF-II transgenic mouse that produces approximately 60% of IGF-II due to a lack of the P2 promoter of this gene. Collectively, this work reveals the fundamental importance of IGF-II in the mature podocyte for glomerular health across mammalian species.


Assuntos
Fator de Crescimento Insulin-Like II/metabolismo , Podócitos/citologia , Podócitos/metabolismo , Transdução de Sinais/fisiologia , Envelhecimento/fisiologia , Animais , Linhagem Celular Transformada , Sobrevivência Celular/fisiologia , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/genética , Glomérulos Renais/citologia , Glomérulos Renais/fisiologia , Células Mesangiais/citologia , Células Mesangiais/metabolismo , Camundongos , Camundongos Transgênicos , RNA Interferente Pequeno/genética
9.
Eur J Clin Nutr ; 66(10): 1120-3, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22892438

RESUMO

BACKGROUND/OBJECTIVES: There is a growing body of evidence that nutritional status influences the morbidity and mortality of children undergoing treatment for cancer. The aim of this paper is to determine if nutritional status is associated with survival post-pediatric bone marrow transplant. SUBJECTS/METHODS: This was a single-center retrospective audit of patients who underwent an autologous or allogeneic hematopoietic stem cell transplant. Patients were divided into three weight categories of underweight, ideal weight and overweight defined by percent ideal body weight. The outcome of interest, overall post transplant survival, was compared between weight categories. RESULTS: Of 113 patients, 15 (13%) were underweight and 41 (36%) were classified as overweight. After adjustment for age, sex, donor source, conditioning therapy and year of transplant, overweight patients were significantly less likely to survive than ideal-weight patients (hazard ratio (HR) 1.91; 95% confidence interval, 1.10-3.31). There was no significant increase in mortality when underweight patients were compared with ideal-weight patients (HR 1.47; 95% confidence interval, 0.57-3.79). CONCLUSIONS: Children who are overweight before hematopoietic stem cell transplantation have decreased survival compared with ideal-weight children.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Neoplasias/complicações , Neoplasias/terapia , Sobrepeso/complicações , Magreza/complicações , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Hospitais Pediátricos , Humanos , Peso Corporal Ideal , Masculino , Prontuários Médicos , Neoplasias/mortalidade , New South Wales/epidemiologia , Queensland/epidemiologia , Estudos Retrospectivos , Caracteres Sexuais , Análise de Sobrevida
10.
Proc Inst Mech Eng H ; 225(11): 1078-83, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22292206

RESUMO

The kinematics of the lumbar spine have previously been described by considering the bearing of the pelvis and lower back. However earlier studies have not described an intersegmental angle measured about a single point; which is necessary for investigation into movement, posture and balance, and lower back pain and injury. This study used computed tomography (CT) scans of 16 pelves to determine the location of palpable bony landmarks, and the junction of the fifth lumbar and first sacral vertebrae within a pelvis axis system. Data were used to derive equations which express the three-dimensional location of the lumbosacral joint centre as an offset from palpable surface landmarks. The magnitude of X, Y, Z offsets was controlled using individual pelvic geometry, and robustness and repeatability of the method was assessed. Regression equations provided the location of the lumbosacral junction to within 8.2mm (+/- 3.4mm) of its true coordinate. Leave-one-out analyses calculated equation coefficients using 15 of the original pelves, with the 16th acting as a control; average errors increased by 6.7 per cent (+/- 0.1 percent). To the authors' knowledge the current method is the most accurate non-invasive means of locating the lumbosacral junction and may be useful for constructing biomechanical models.


Assuntos
Articulações/anatomia & histologia , Articulações/fisiopatologia , Antropometria , Artefatos , Fenômenos Biomecânicos , Estudos de Viabilidade , Humanos , Região Lombossacral , Modelos Anatômicos , Movimento (Física) , Palpação , Pelve/anatomia & histologia , Pelve/fisiopatologia , Equilíbrio Postural , Análise de Regressão , Reprodutibilidade dos Testes , Coluna Vertebral/fisiopatologia , Tomografia Computadorizada por Raios X/métodos
11.
Curr Pharm Des ; 16(37): 4134-47, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21247394

RESUMO

Cardiovascular disease remains the leading cause of morbidity and mortality globally. The disease is largely controlled with interventions managing atherogenic lipids including LDL and triglycerides. However a number of studies have shown that increasing HDL levels is likely to provide better outcomes for patients suffering from this disease. There has been an extensive research effort into understanding how HDL levels are regulated in the body and which pathways can be targeted therapeutically. The HDL metabolic pathway is however overwhelmingly complex. This has provided only limited success in trialing drugs designed to raise HDL. To add to the complexity HDL itself is a heterogeneous population of particles and there is controversy surrounding which HDL particle is the most cardio-protective. In addition there is varying opinions on which of the HDL cellular receptors are more important in humans (as opposed to what has been discovered in mice) in regulating these effects. In this article we explore the evidence for and against using the currently suggested methods of raising HDL and provide some evidence for how the adverse effects of these drugs could be corrected.


Assuntos
Aterosclerose/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , HDL-Colesterol/sangue , Doença da Artéria Coronariana/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Reguladores do Metabolismo de Lipídeos/uso terapêutico , Animais , Aterosclerose/metabolismo , Doenças Cardiovasculares/complicações , LDL-Colesterol/sangue , Ensaios Clínicos como Assunto , Doença da Artéria Coronariana/etiologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Reguladores do Metabolismo de Lipídeos/efeitos adversos , Camundongos , Fatores de Risco , Triglicerídeos/sangue
12.
Ann Rheum Dis ; 68(10): 1602-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19528034

RESUMO

BACKGROUND: Monosodium urate (MSU) and calcium pyrophosphate dihydrate (CPPD) crystal-induced interleukin 1 beta (IL1beta) release contributes to inflammation in subcutaneous air pouch and peritoneal models of acute gout and pseudogout. However, consequences of IL1 inhibition have not been explored in more clinically relevant models of crystal-induced arthritis. OBJECTIVE: To develop a novel mouse model of acute gouty ankle arthritis and use it to assess the effects of genetic deletion of IL1 receptor type (IL1R1) and of exogenous mIL1 Trap (a high-affinity blocker of mouse IL1alpha and IL1beta) on pain, synovitis and systemic inflammatory biomarkers. METHODS: MSU crystals were injected into the mouse ankle joint and pain and ankle swelling were measured over 4 days. The effects of IL1 inhibition were determined in this model, and in the comparator models of crystal-induced peritonitis and subcutaneous air pouch inflammation. RESULTS: Both IL1R1-null mice and mice pretreated with mIL1 Trap showed reduced neutrophil influx in MSU and CPPD crystal-induced peritonitis and air pouch models (p<0.05). In the ankle joint model, both IL1R1 knockout mice and pretreatment with mIL1 Trap were associated with significant reductions in MSU crystal-induced elevations in hyperalgesia, inflammation, serum amyloid A and the levels of multiple inflammatory cytokines and chemokines (p<0.05). Additionally, it was found that administration of mIL1 Trap after MSU crystal injection reduced established hyperalgesia and ankle swelling. CONCLUSIONS: IL1 inhibition both prevented and relieved pain and ankle joint inflammation in response to intra-articular MSU crystals in mice. Results suggested that IL1 Trap has the potential to both prevent and treat gouty arthritis.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Gotosa/tratamento farmacológico , Supressores da Gota/uso terapêutico , Hiperalgesia/prevenção & controle , Proteínas Recombinantes de Fusão/uso terapêutico , Sinovite/prevenção & controle , Animais , Artrite Experimental/complicações , Artrite Gotosa/complicações , Biomarcadores/metabolismo , Colchicina/uso terapêutico , Citocinas/biossíntese , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Hiperalgesia/etiologia , Interleucina-1/antagonistas & inibidores , Masculino , Camundongos , Camundongos Knockout , Infiltração de Neutrófilos , Receptores Tipo I de Interleucina-1/deficiência , Receptores Tipo I de Interleucina-1/genética , Transdução de Sinais/fisiologia , Sinovite/etiologia , Regulação para Cima/efeitos dos fármacos , Ácido Úrico
13.
Curr Med Chem ; 16(6): 667-75, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19199930

RESUMO

It is well recognised that increased levels of high density lipoprotein (HDL) protect against atherosclerosis and correlate with improved prognosis for vascular disease associated events. While many of the atheroprotective effects of HDL are ascribed to the ability to remove cholesterol from the vasculature through the reverse cholesterol transport system, recent work has shown that HDL may be atheroprotective through its other functions, such as regulation of endothelial adhesion molecule expression, stimulation of endothelial nitric oxide synthase and inhibition of the damaging effects of oxidised low density lipoproteins. Recently, HDL has also been described to interact with circulating cells inhibiting both leukocyte and platelet activation, therefore having further systemic anti-inflammatory functions. This review summarises the studies and models used to examine the anti-inflammatory effects of HDL and details data describing the ability to inhibit leukocyte activation, contributing to the hypothesis that raised HDL is beneficial in the context of inflammation in atherosclerosis. Further, HDL modification in disease and current therapeutic strategies such as reconstituted HDL particles and apoA I mimetic peptides is discussed to provide insights to the potential applicability of raising HDL to regress cardiovascular disease.


Assuntos
Inflamação/metabolismo , Lipoproteínas HDL/metabolismo , Animais , Humanos , Camundongos , Ratos
14.
Eur Respir J ; 33(6): 1287-94, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19196819

RESUMO

Vascular endothelial growth factor (VEGF) is an angiogenic factor implicated in asthma severity. The objective of the present study was to determine whether VEGF single nucleotide polymorphisms (SNPs) are associated with asthma, lung function and airway responsiveness. The present authors analysed 10 SNPs in 458 white families in the Childhood Asthma Management Program (CAMP). Tests of association with asthma, lung function and airway responsiveness were performed using PBAT software (Golden Helix, Inc. Bozeman, MT, USA; available at www.goldenhelix.com). Family and population-based, revpeated measures analysis of airflow obstruction were conducted. Replication studies were performed in 412 asthmatic children and their parents from Costa Rica. Associations with asthma, lung function and airway responsiveness were observed in both cohorts. SNP rs833058 was associated with asthma in both cohorts. This SNP was also associated with increased airway responsiveness in both populations. An association of rs4711750 and its haplotype with forced expiratory volume in 1 s (FEV(1))/forced vital capacity (FVC) ratio in both cohorts was observed. Longitudinal analysis in CAMP confirmed an association of rs4711750 with FEV(1)/FVC decline over approximately 4.5 yrs of observation. VEGF polymorphisms are associated with childhood asthma, lung function and airway responsiveness in two populations, suggesting that VEGF polymorphisms influence asthma susceptibility, airflow obstruction and airways responsiveness.


Assuntos
Asma/genética , Asma/fisiopatologia , Fator A de Crescimento do Endotélio Vascular/genética , Adolescente , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Antiasmáticos/administração & dosagem , Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Testes de Provocação Brônquica , Criança , Costa Rica , Método Duplo-Cego , Feminino , Volume Expiratório Forçado , Genótipo , Haplótipos , Humanos , Masculino , Nedocromil/administração & dosagem , Nedocromil/uso terapêutico , Fenótipo , Placebos , Polimorfismo de Nucleotídeo Único , Análise de Regressão , Testes de Função Respiratória , Software , Capacidade Vital , População Branca/genética
15.
Microb Pathog ; 45(4): 241-57, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18586081

RESUMO

We hypothesized that particular genetic backgrounds enhance rates of colonization, increase severity of enteritis, and allow for extraintestinal spread when inbred IL-10(-/-) mice are infected with pathogenic C. jejuni. Campylobacter jejuni stably colonized C57BL/6 and NOD mice, while congenic strains lacking IL-10 developed typhlocolitis following colonization that mimicked human campylobacteriosis. However, IL-10 deficiency alone was not necessary for the presence of C. jejuni in extraintestinal sites. C3H/HeJ tlr4(-/-) mice that specifically express the Cdcs1 allele showed colonization and limited extraintestinal spread without enteritis implicating this interval in the clinical presentation of C. jejuni infection. Furthermore, when the IL-10 gene is inactivated as in C3Bir tlr4(-/-) IL-10(-/-) mice, enteritis and intensive extraintestinal spread were observed, suggesting that clinical presentations of C. jejuni infection are controlled by a complex interplay of factors. These data demonstrate that lack of IL-10 had a greater effect on C. jejuni induced colitis than other immune elements such as TLR4 (C3H/HeJ, C3Bir IL-10(-/-)), MHC H-2g7, diabetogenic genes, and CTLA-4 (NOD) and that host genetic background is in part responsible for disease phenotype. C3Bir IL-10(-/-) mice where Cdcs1 impairs gut barrier function provide a new murine model of C. jejuni and can serve as surrogates for immunocompromised patients with extraintestinal spread.


Assuntos
Infecções por Campylobacter/genética , Campylobacter jejuni/fisiologia , Enterite/microbiologia , Interações Hospedeiro-Patógeno , Interleucina-10/imunologia , Animais , Anticorpos Antibacterianos/sangue , Infecções por Campylobacter/imunologia , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/patologia , Campylobacter jejuni/imunologia , Campylobacter jejuni/patogenicidade , Enterite/genética , Enterite/imunologia , Enterite/patologia , Humanos , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Fenótipo
16.
Vet Parasitol ; 153(1-2): 24-43, 2008 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-18342449

RESUMO

We tested the hypothesis that brown-headed cowbirds (Molothrus ater) harbor Sarcocystis neurona, the agent of equine protozoal myeloencephalitis (EPM), and act as intermediate hosts for this parasite. In summer 1999, wild caught brown-headed cowbirds were collected and necropsied to determine infection rate with Sarcocystis spp. by macroscopic inspection. Seven of 381 (1.8%) birds had grossly visible sarcocysts in leg muscles with none in breast muscles. Histopathology revealed two classes of sarcocysts in leg muscles, thin-walled and thick-walled suggesting two species. Electron microscopy showed that thick-walled cysts had characteristics of S. falcatula and thin-walled cysts had characteristics of S. neurona. Thereafter, several experiments were conducted to confirm that cowbirds had viable S. neurona that could be transmitted to an intermediate host and cause disease. Specific-pathogen-free opossums fed cowbird leg muscle that was enriched for muscle either with or without visible sarcocysts all shed high numbers of sporocysts by 4 weeks after infection, while the control opossum fed cowbird breast muscle was negative. These sporocysts were apparently of two size classes, 11.4+/-0.7 microm by 7.6+/-0.4 microm (n=25) and 12.6+/-0.6 microm by 8.0+/-0 microm (n=25). When these sporocysts were excysted and introduced into equine dermal cell tissue culture, schizogony occurred, most merozoites survived and replicated long term and merozoites sampled from the cultures with long-term growth were indistinguishable from known S. neurona isolates. A cowbird Sarcocystis isolate, Michigan Cowbird 1 (MICB1), derived from thin-walled sarcocysts from cowbirds that was passaged in SPF opossums and tissue culture went on to produce neurological disease in IFNgamma knockout mice indistinguishable from that of the positive control inoculated with S. neurona. This, together with the knowledge that S. falcatula does not cause lesions in IFNgamma knockout mice, showed that cowbird leg muscles had a Sarcocystis that fulfills the first aim of Koch's postulates to produce disease similar to S. neurona. Two molecular assays provided further support that both S. neurona and S. falcatula were present in cowbird leg muscles. In a blinded study, PCR-RFLP of RAPD-derived DNA designed to discriminate between S. neurona and S. falcatula showed that fresh sporocysts from the opossum feeding trial had both Sarcocystis species. Visible, thick-walled sarcocysts from cowbird leg muscle were positive for S. falcatula but not S. neurona; thin-walled sarcocysts typed as S. neurona. In 1999, DNA was extracted from leg muscles of 100 wild caught cowbirds and subjected to a PCR targeting an S. neurona specific sequence of the small subunit ribosomal RNA (SSU rRNA) gene. In control spiking experiments, this assay detected DNA from 10 S. neurona merozoites in 0.5g of muscle. In the 1999 experiment, 23 of 79 (29.1%) individual cowbird leg muscle samples were positive by this S. neurona-specific PCR. Finally, in June of 2000, 265 cowbird leg muscle samples were tested by histopathology for the presence of thick- and thin-walled sarcocysts. Seven percent (18/265) had only thick-walled sarcocysts, 0.8% (2/265) had only thin-walled sarcocysts and 1.9% (5/265) had both. The other half of these leg muscles when tested by PCR-RFLP of RAPD-derived DNA and SSU rRNA PCR showed a good correlation with histopathological results and the two molecular typing methods concurred; 9.8% (26/265) of cowbirds had sarcocysts in muscle, 7.9% (21/265) had S. falcatula sarcocysts, 1.1% (3/265) had S. neurona sarcocysts, and 0.8% (2/265) had both. These results show that some cowbirds have S. neurona as well as S. falcatula in their leg muscles and can act as intermediate hosts for both parasites.


Assuntos
Doenças das Aves/parasitologia , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Aves Canoras/parasitologia , Animais , Cavalos , Interações Hospedeiro-Parasita , Interferon gama/genética , Interferon gama/metabolismo , Camundongos , Camundongos Knockout , Músculo Esquelético/parasitologia , Gambás/parasitologia , Filogenia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Sarcocystis/genética , Sarcocistose/parasitologia , Sensibilidade e Especificidade , Pele/citologia , Pele/parasitologia , Organismos Livres de Patógenos Específicos
17.
Kidney Int ; 73(2): 181-91, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17943079

RESUMO

Once developed, end-stage renal disease cannot be reversed by any current therapy. Bone morphogenetic protein-7 (BMP-7), however, is a possible treatment for reversing end-stage renal disease. Previously, we showed that the BMP antagonist uterine sensitization-associated gene-1 (USAG-1, also known as ectodin and sclerostin domain-containing 1) negatively regulates the renoprotective action of BMP-7. Here, we show that the ratio between USAG-1 and BMP-7 expression increased dramatically in the later stage of kidney development, with USAG-1 expression overlapping BMP-7 only in differentiated distal tubules. Examination of USAG-1 expression in developing kidney indicated that a mosaic of proximal and distal tubule marker-positive cells reside side by side in the immature nephron. This suggests that each cell controls its own fate for becoming a proximal or distal tubule cell. In kidney injury models, the ratio of USAG-1 to BMP-7 expression decreased with kidney damage but increased after subsequent kidney regeneration. Our study suggests that USAG-1 expression in a kidney biopsy could be useful in predicting outcome.


Assuntos
Proteínas Morfogenéticas Ósseas/análise , Túbulos Renais/química , Túbulos Renais/embriologia , Fator de Crescimento Transformador beta/análise , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteína Morfogenética Óssea 7 , Proteínas Morfogenéticas Ósseas/genética , Diferenciação Celular , Cisplatino/toxicidade , Feminino , Túbulos Renais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Néfrons/química , Prognóstico , Regeneração , Fator de Crescimento Transformador beta/genética
18.
Diabetologia ; 50(8): 1770-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17579831

RESUMO

AIMS/HYPOTHESIS: AGE contribute to the pathogenesis of diabetic complications, including dyslipidaemia and atherosclerosis. However, the precise mechanisms remain to be established. In the present study, we examined whether AGE modification of apolipoprotein A-I (apoA-I) affects its functionality, thus altering its cardioprotective profile. MATERIALS AND METHODS: The ability of AGE-modified apoA-I to facilitate cholesterol and phospholipid efflux, stabilise ATP-binding cassette transporter A1 (ABCA1) and inhibit expression of adhesion molecules in human macrophages and monocytes was studied. RESULTS: The ability of AGE-modified apoA-I to promote cholesterol efflux from THP-1 macrophages, isolated human monocytes and from ABCA1-transfected HeLa cells was significantly reduced (>70%) compared with unmodified apoA-I. This effect was reversed by preventing AGE formation with aminoguanidine or reversing AGE modification using the cross-link breaker alagebrium chloride. AGE-modification of HDL also reduced its capacity to promote cholesterol efflux. AGE-apoA-I was also less effective than apoA-I in stabilising ABCA1 in THP-1 cells as well as in inhibiting expression of CD11b in human monocytes. CONCLUSIONS/INTERPRETATION: AGE modification of apoA-I considerably impairs its cardioprotective, antiatherogenic properties, including the ability to promote cholesterol efflux, stabilise ABCA1 and inhibit the expression of adhesion molecules. These findings provide a rationale for targeting AGE in the management of diabetic dyslipidaemia.


Assuntos
Apolipoproteína A-I/metabolismo , Aterosclerose/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/fisiologia , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Antígeno CD11b/metabolismo , Linhagem Celular , Células Cultivadas , Colesterol/metabolismo , Eletroforese em Gel de Poliacrilamida , Glicosilação/efeitos dos fármacos , Guanidinas/farmacologia , Células HeLa , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoproteínas HDL/metabolismo , Fosfolipídeos/metabolismo , Ribose/metabolismo , Tiazóis/farmacologia , Transfecção
19.
Histopathology ; 50(2): 243-51, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17222253

RESUMO

AIMS: Alpha-methylacyl-CoA racemase (AMACR) is a sensitive and specific immunohistochemical marker of prostatic malignancy, staining 80-100% of prostatic cancers with absent staining in benign glands. However, positive staining in benign conditions as well as low rates of AMACR reactivity in prostatic cancer variants have been described. Preliminary use of AMACR immunohistochemistry in our institution has suggested lower specificity and sensitivity for prostatic cancer than initially proposed. The aim of this study was to establish true rates of AMACR reactivity in prostatic cancer and benign prostatic hyperplasia (BPH). METHODS AND RESULTS: AMACR immunohistochemistry was performed on sections from 57 prostatic cancers and 44 BPH resections. Ninety-one percent of cancers were AMACR+, with diffuse (> 75%) tumour staining in 53% of cases. Thirty-eight percent of tumours showed heterogeneous expression (1-75% tumour staining). This was significantly correlated with increased Gleason score. High-grade prostatic intraepithelial neoplasia (PIN) was AMACR+ in 87% of cancers. Eleven percent of BPH showed moderate or strong staining in benign glands, focally mimicking the malignant staining pattern. CONCLUSIONS: This study confirms heterogeneous AMACR expression in prostatic cancer and shows a correlation with Gleason score. Positive staining in BPH is also documented, thus emphasizing the importance of interpreting AMACR immunohistochemistry in the context of other findings in a diagnostic setting.


Assuntos
Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/enzimologia , Racemases e Epimerases/biossíntese , Racemases e Epimerases/genética , Índice de Gravidade de Doença , Humanos , Masculino , Neoplasias da Próstata/patologia
20.
Infect Immun ; 75(3): 1099-115, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17130251

RESUMO

Campylobacter jejuni is a globally distributed cause of human food-borne enteritis and has been linked to chronic joint and neurological diseases. We hypothesized that C. jejuni 11168 colonizes the gastrointestinal tract of both C57BL/6 mice and congenic C57BL/6 interleukin-10-deficient (IL-10(-/-)) mice and that C57BL/6 IL-10(-/-) mice experience C. jejuni 11168-mediated clinical signs and pathology. Individually housed mice were challenged orally with C. jejuni 11168, and the course of infection was monitored by clinical examination, bacterial culture, C. jejuni-specific PCR, gross pathology, histopathology, immunohistochemistry, and anti-C. jejuni-specific serology. Ceca of C. jejuni 11168-infected mice were colonized at high rates: ceca of 50/50 wild-type mice and 168/170 IL-10(-/-) mice were colonized. In a range from 2 to 35 days after infection with C. jejuni 11168, C57BL/6 IL-10(-/-) mice developed severe typhlocolitis best evaluated at the ileocecocolic junction. Rates of colonization and enteritis did not differ between male and female mice. A dose-response experiment showed that as little as 10(6) CFU produced significant disease and pathological lesions similar to responses seen in humans. Immunohistochemical staining demonstrated C. jejuni antigens within gastrointestinal tissues of infected mice. Significant anti-C. jejuni plasma immunoglobulin levels developed by day 28 after infection in both wild-type and IL-10-deficient animals; antibodies were predominantly T-helper-cell 1 (Th1)-associated subtypes. These results indicate that the colonization of the mouse gastrointestinal tract by C. jejuni 11168 is necessary but not sufficient for the development of enteritis and that C57BL/6 IL-10(-/-) mice can serve as models for the study of C. jejuni enteritis in humans.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter jejuni/patogenicidade , Enterite/microbiologia , Interleucina-10/deficiência , Interleucina-10/genética , Animais , Animais Congênicos , Infecções por Campylobacter/genética , Infecções por Campylobacter/imunologia , Modelos Animais de Doenças , Enterite/genética , Enterite/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
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