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1.
Hum Mol Genet ; 32(16): 2646-2655, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37369012

RESUMO

Animal studies implicate one-carbon metabolism and DNA methylation genes in hepatocellular carcinoma (HCC) development in the setting of metabolic perturbations. Using human samples, we investigated the associations between common and rare variants in these closely related biochemical pathways and risk for metabolic HCC development in a multicenter international study. We performed targeted exome sequencing of 64 genes among 556 metabolic HCC cases and 643 cancer-free controls with metabolic conditions. Multivariable logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for multiple comparisons. Gene-burden tests were used for rare variant associations. Analyses were performed in the overall sample and among non-Hispanic whites. The results show that among non-Hispanic whites, presence of rare functional variants in ABCC2 was associated with 7-fold higher risk of metabolic HCC (OR = 6.92, 95% CI: 2.38-20.15, P = 0.0004), and this association remained significant when analyses were restricted to functional rare variants observed in ≥2 participants (cases 3.2% versus controls 0.0%, P = 1.02 × 10-5). In the overall multiethnic sample, presence of rare functional variants in ABCC2 was nominally associated with metabolic HCC (OR = 3.60, 95% CI: 1.52-8.58, P = 0.004), with similar nominal association when analyses were restricted to functional rare variants observed in ≥2 participants (cases 2.9% versus controls 0.2%, P = 0.006). A common variant in PNPLA3 (rs738409[G]) was associated with higher HCC risk in the overall sample (P = 6.36 × 10-6) and in non-Hispanic whites (P = 0.0002). Our findings indicate that rare functional variants in ABCC2 are associated with susceptibility to metabolic HCC in non-Hispanic whites. PNPLA3-rs738409 is also associated with metabolic HCC risk.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Metilação de DNA/genética , Predisposição Genética para Doença , Estudos de Casos e Controles , Células Germinativas/patologia , Carbono , Polimorfismo de Nucleotídeo Único/genética
2.
Environ Monit Assess ; 192(1): 67, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31879802

RESUMO

Optical sensing of chlorophyll-a (chl-a), turbidity, and fluorescent dissolved organic matter (fDOM) is often used to characterize the quality of water. There are many site-specific factors and environmental conditions that can affect optically sensed readings; notwithstanding the comparative implication of different procedures used to measure these properties in the laboratory. In this study, we measured these water quality properties using standard laboratory methods, and in the field using optical sensors (sonde-based) at water quality monitoring sites located in four watersheds in Canada. The overall objective of this work was to explore the relationships among sonde-based and standard laboratory measurements of the aforementioned water properties, and evaluate associations among these eco-hydrological properties and land use, environmental, and ancillary water quality variables such as dissolved organic carbon (DOC) and total suspended solids (TSS). Differences among sonde versus laboratory relationships for chl-a suggest such relationships are impacted by laboratory methods and/or site specific conditions. Data mining analysis indicated that interactive site-specific factors predominately impacting chl-a values across sites were specific conductivity and turbidity (variables with positive global associations with chl-a). The overall linear regression predicting DOC from fDOM was relatively strong (R2 = 0.77). However, slope differences in the watershed-specific models suggest laboratory DOC versus fDOM relationships could be impacted by unknown localized water quality properties affecting fDOM readings, and/or the different standard laboratory methods used to estimate DOC. Artificial neural network analyses (ANN) indicated that higher relative chl-a concentrations were associated with low to no tree cover around sample sites and higher daily rainfall in the watersheds examined. Response surfaces derived from ANN indicated that chl-a concentrations were higher where combined agricultural and urban land uses were relatively higher.


Assuntos
Clorofila A/análise , Monitoramento Ambiental/métodos , Substâncias Húmicas/análise , Hidrodinâmica , Rios/química , Qualidade da Água/normas , Agricultura , Colúmbia Britânica , Ecologia , Fluorometria , Ontário , Urbanização
3.
Analyst ; 144(1): 324-330, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30516175

RESUMO

The spirits drinks industry is of significant global economic importance and a major employer worldwide, and the ability to ensure product authenticity and maintain consumer confidence in these high-value products is absolutely essential. Spirit drinks counterfeiting is a worldwide problem, with counterfeiting and adulteration of spirit drinks taking many forms, such as substitution, stretching with lower-grade products, or creation of counterfeits with industrial, surrogate, or locally produced alcohols. Methanol for example, which has been used as a substitute alcohol for ethanol, has a high toxicity in humans. The counterfeiting of spirit drinks is consequently one of the few leading reported types of food fraud which can be directly and unequivocally linked to food safety and health concerns. Here, for the first time, we use handheld Raman spectroscopy with excitation in the near IR (1064 nm) for the through-container differentiation of multiple spirit drinks, detection of multiple chemical markers of counterfeit alcohol, and for the quantification of methanol. We established the limits of detection (LOD) of methanol in the analysed samples from four different spirit types (between 0.23-0.39%), which were considerably lower than a quoted maximum tolerable concentration (MTC) of 2% (v/v) methanol for humans in a 40% alcohol by volume (ABV) spirit drink, and even lower than the general EU limit for naturally occurring methanol in fruit spirits of 0.5% v/v (10 g methanol per L ethanol). We believe that Raman spectroscopy has considerable practicable potential for the rapid in situ through-container detection of counterfeit spirits drinks, as well as for the analysis and protection of other beverages and liquid samples.


Assuntos
Bebidas Alcoólicas/análise , Contaminação de Alimentos/análise , Metanol/análise , Análise Espectral Raman/métodos , Inocuidade dos Alimentos/métodos , Limite de Detecção , Análise de Componente Principal , Análise Espectral Raman/instrumentação
4.
J Public Health (Oxf) ; 38(3): 585-590, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26045472

RESUMO

BACKGROUND: The burden of disease relating to undiagnosed HIV infection is significant in the UK. BHIVA (British HIV Association) recommends population screening in high prevalence areas, expanding outside traditional antenatal/GUM settings. METHODS: RUClear 2011-12 piloted expanding HIV testing outside traditional settings using home-sampling kits (dry-blood-spot testing) ordered online. Greater Manchester residents (≥age 16) could request testing via an established, online chlamydia testing service (www.ruclear.co.uk). Participant attitudes towards this new service were assessed. Qualitative methods (thematic analysis) were used to analyse free-text data submitted by participants via hard copy questionnaires issued in all testing kits. RESULTS: 79.9% (2447/3062) participants completed questionnaires, of which 30.9% (756/2447) provided free-text data. Participants overwhelmingly supported the service, valuing particularly accessibility and convenience, allowing individuals to order tests any time of day and self-sample comfortably at home; avoiding the invasive nature of venipuncture and avoiding the need for face-to-face interaction with health services. The pilot was also clinically and cost-effective. CONCLUSION: Testing via home-sampling kits ordered online (dry-blood-spot testing) was felt to be an acceptable and convenient method for accessing a HIV test. Many individuals undertook HIV testing where they would otherwise not have been tested at all. Expansion of similar services may increase the uptake of HIV testing.


Assuntos
Atitude Frente a Saúde , Infecções por HIV/diagnóstico , Autocuidado/psicologia , Adolescente , Adulto , Idoso , Teste em Amostras de Sangue Seco/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Reino Unido , Adulto Jovem
5.
Cryo Letters ; 37(5): 318-329, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27924999

RESUMO

BACKGROUND: Cryobanks are a secure, efficient and low cost method for the long-term conservation of plant genetic resources for theoretically centuries or millennia with minimal maintenance. OBJECTIVE: The present manuscript describes CIP's modified protocol for potato cryopreservation, its large-scale application, and the establishment of quality and operational standards, which included a viability reassessment of material entering the cryobank. MATERIALS AND METHODS: In 2013, CIP established stricter quality and operational standards under which 1,028 potato accessions were cryopreserved with an improved PVS2-droplet protocol. In 2014 the viability of 114 accessions cryopreserved in 2013 accessions were reassessed. RESULTS: The average recovery rate (full plant recovery after LN exposure) of 1028 cryopreserved Solanum species ranged from 34 to 59%, and 70% of the processed accessions showed a minimum recovery rate of ≥20% and were considered as successfully cryopreserved. CONCLUSION: CIP has established a new high quality management system for cryobanking. Periodic viability reassessment, strict and clear recovery criteria and the monitoring of the percent of successful accessions meeting the criteria as well as contamination rates are metrics that need to be considered in cryobanks.


Assuntos
Conservação dos Recursos Naturais/métodos , Criopreservação/métodos , Variação Genética , Solanum tuberosum/fisiologia , Solanum tuberosum/genética
6.
Osteoarthritis Cartilage ; 23(12): 2158-2166, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26067518

RESUMO

OBJECTIVE: The aim of this work is to establish the human metacarpal as a new whole joint surface early-stage osteoarthritis (OA) model that enables comparisons of articular cartilage and subchondral bone through high resolution contrast-enhanced CT (CECT) imaging, mechanical testing, and biochemical analysis. DESIGN: The fourth metacarpal was obtained from 12 human cadaveric donors and baseline µCT imaging was followed by indentation testing. The samples were then immersed in anionic (Ioxaglate) and cationic (CA4+) iodinated contrast agent solutions followed by CECT. Cartilage GAG content and distribution was measured using the 1,9 dimethylmethylene blue (DMMB) assay and Safranin-O histology staining. Linear regression was performed to compare cartilage and subchondral bone properties. RESULTS: Strong and significant positive correlations were observed between CA4+ CECT attenuation and both GAG content (R(2) = 0.86) and equilibrium modulus (R(2) = 0.84), while correlations using Ioxaglate were insignificant (R(2) ≤ 0.24, P > 0.05). Subchondral bone plate (SBP) thickness negatively and significantly correlated with SBP mineral density (R(2) = 0.49). Cartilage GAG content significantly correlated with several trabecular bone properties, including positive correlations with bone volume fraction (%BV/TV, R(2) = 0.67), trabecular number (Tb.N, R(2) = 0.60), and trabecular thickness (R(2) = 0.42), and negative relationships with structural model index (SMI, R(2) = 0.78) and trabecular spacing (Tb.Sp, R(2) = 0.56). Similarly, equilibrium modulus correlated positively with %BV/TV (R(2) = 0.50), Tb.N (R(2) = 0.59) and negatively with Tb.Sp (R(2) = 0.55) and SMI (R(2) = 0.60). CONCLUSION: This study establishes the human metacarpal as a new early-stage OA model suitable for rapid, high resolution CECT imaging, mechanical testing, and biochemical analysis of the cartilage and subchondral bone, and for examining their inter-relationships.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Ossos Metacarpais/diagnóstico por imagem , Articulação Metacarpofalângica/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Cadáver , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Força Compressiva , Meios de Contraste , Feminino , Glicosaminoglicanos/metabolismo , Humanos , Ácido Ioxáglico , Modelos Lineares , Masculino , Ossos Metacarpais/metabolismo , Ossos Metacarpais/patologia , Articulação Metacarpofalângica/metabolismo , Articulação Metacarpofalângica/patologia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Microtomografia por Raio-X
7.
Proc Natl Acad Sci U S A ; 109(52): 21462-7, 2012 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-23236168

RESUMO

Polycystic kidney diseases are the most common genetic diseases that affect the kidney. There remains a paucity of information regarding mechanisms by which G proteins are regulated in the context of polycystic kidney disease to promote abnormal epithelial cell expansion and cystogenesis. In this study, we describe a functional role for the accessory protein, G-protein signaling modulator 1 (GPSM1), also known as activator of G-protein signaling 3, to act as a modulator of cyst progression in an orthologous mouse model of autosomal dominant polycystic kidney disease (ADPKD). A complete loss of Gpsm1 in the Pkd1(V/V) mouse model of ADPKD, which displays a hypomorphic phenotype of polycystin-1, demonstrated increased cyst progression and reduced renal function compared with age-matched cystic Gpsm1(+/+) and Gpsm1(+/-) mice. Electrophysiological studies identified a role by which GPSM1 increased heteromeric polycystin-1/polycystin-2 ion channel activity via Gßγ subunits. In summary, the present study demonstrates an important role for GPSM1 in controlling the dynamics of cyst progression in an orthologous mouse model of ADPKD and presents a therapeutic target for drug development in the treatment of this costly disease.


Assuntos
Proteínas de Transporte/metabolismo , Progressão da Doença , Rim Policístico Autossômico Dominante/metabolismo , Rim Policístico Autossômico Dominante/patologia , Animais , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos , Imunofluorescência , Genótipo , Inibidores de Dissociação do Nucleotídeo Guanina , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Testes de Função Renal , Camundongos , Rim Policístico Autossômico Dominante/fisiopatologia , Transporte Proteico , Canais de Cátion TRPP/metabolismo
8.
J Fish Biol ; 86(6): 1867-72, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25898908

RESUMO

A dense aggregation of skate egg cases was imaged during a photographic survey of the sea floor along the western Antarctic Peninsula in November 2013. Egg cases were noted in a narrow band between 394 and 443 m depth. Although some skate species in other oceans are known to utilize restricted areas to deposit eggs in great numbers, such nurseries have not been described in the Southern Ocean.


Assuntos
Ecossistema , Oviposição , Rajidae , Animais , Regiões Antárticas , Oceanos e Mares , Óvulo
9.
J Antimicrob Chemother ; 69(8): 2210-4, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24788656

RESUMO

OBJECTIVES: Species-specific clinical breakpoints (CBPs) for Candida spp. were established following consideration of clinical outcomes in patients with oesophageal candidiasis. We sought to further determine the validity of the current CBPs based on data from a prospective candidaemia study. PATIENTS AND METHODS: All Candida albicans candidaemia episodes in patients enrolled in the Australian Candidaemia Study and who were treated with fluconazole monotherapy were included. Fluconazole MICs were established using Sensititre(®) YeastOne(®). RESULTS: Two hundred and seventeen evaluable episodes were identified, 93.5% of which occurred in adult patients. Fluconazole was commenced within 72 h of blood culture positivity in 96.3% (209/217) of episodes. Fluconazole doses were appropriate in 89.9% (195/217) of episodes and the median duration of therapy was 14 days (IQR 8-21 days) for the whole cohort. The all-cause 30 day mortality was 19.8% (43/217), with 37.2% (16/43) of deaths attributed to candidaemia. Classification and regression tree (CART) analysis identified a fluconazole MIC target of ≥2 mg/L for infection-related mortality and ≥4 mg/L for overall 30 day mortality. Overall mortality was no different in episodes with isolates above or below the identified MIC target, although there was a trend towards significance (P = 0.051). On univariate analysis, infection-related mortality was significantly increased in C. albicans episodes with an MIC ≥2 mg/L compared with those below this MIC target (20.6% versus 4.9%; P = 0.001). This target remained an independent predictor of infection-related mortality (OR 8.2; 95% CI 2.3-29.7; P = 0.001). CONCLUSIONS: We observed a direct relationship between infection-related mortality and rising fluconazole MIC for C. albicans candidaemia; overall, the data support the EUCAST and revised CLSI fluconazole clinical breakpoints.


Assuntos
Candidemia/tratamento farmacológico , Candidemia/mortalidade , Doenças do Esôfago/tratamento farmacológico , Doenças do Esôfago/mortalidade , Fluconazol/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Candidemia/microbiologia , Criança , Pré-Escolar , Estudos de Coortes , Farmacorresistência Fúngica , Doenças do Esôfago/microbiologia , Feminino , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
10.
Pediatr Res ; 75(1-2): 148-57, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24336431

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) are significant causes of morbidity and mortality in children and young adults. ADPKD, with an incidence of 1:400 to 1:1,000, affects more than 13 million individuals worldwide and is a major cause of end-stage renal disease in adults. However, symptomatic disease is increasingly recognized in children. ARPKD is a dual-organ hepatorenal disease with an incidence of 1:20,000 to 1:40,000 and a heterozygote carrier rate of 1 in 70. Currently, no clinically significant disease-specific therapy exists for ADPKD or ARPKD. The genetic basis of both ADPKD and ARPKD have been identified, and delineation of the basic molecular and cellular pathophysiology has led to the discovery that abnormal ADPKD and ARPKD gene products interact to create "polycystin complexes" located at multiple sites within affected cells. The extracellular matrix and vessels produce a variety of soluble factors that affect the biology of adjacent cells in many dynamic ways. This review will focus on the molecular and cellular bases of the abnormal cystic phenotype and discuss the clinical translation of such basic data into new therapies that promise to alter the natural history of disease for children with genetic PKDs.


Assuntos
Rim/fisiopatologia , Rim Policístico Autossômico Dominante/fisiopatologia , Rim Policístico Autossômico Recessivo/fisiopatologia , Adolescente , Fatores Etários , Animais , Criança , Pré-Escolar , Predisposição Genética para Doença , Humanos , Incidência , Lactente , Rim/metabolismo , Fenótipo , Rim Policístico Autossômico Dominante/epidemiologia , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Rim Policístico Autossômico Dominante/terapia , Rim Policístico Autossômico Recessivo/epidemiologia , Rim Policístico Autossômico Recessivo/genética , Rim Policístico Autossômico Recessivo/metabolismo , Rim Policístico Autossômico Recessivo/terapia , Prognóstico , Fatores de Risco , Transdução de Sinais
11.
J Am Soc Nephrol ; 24(12): 2010-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23990677

RESUMO

Past efforts to pharmacologically disrupt the development and growth of renal cystic lesions focused primarily on normalizing the activity of a specific signaling molecule, but the effects of stimulating apoptosis in the proliferating epithelial cells have not been well studied. Although benign, ADPKD renal cysts created by the sustained proliferation of epithelial cells resemble tumors, and malignant cell death can be achieved by cotreatment with TNF-α and a mimetic of second mitochondria-derived activator of caspase (Smac). Notably, TNF-α accumulates to high levels in ADPKD cyst fluid. Here, we report that an Smac-mimetic selectively induces TNF-α-dependent cystic renal epithelial cell death, leading to the removal of cystic epithelial cells from renal tissues and delaying cyst formation. In vitro, a Smac-mimetic (GT13072) induced the degradation of cIAP1 that is required but not sufficient for cell death. Cotreatment with TNF-α augmented the formation and activation of the RIPK1-dependent death complex and the degradation and cleavage of FLIP, an inhibitor of caspase-8, in renal cystic epithelial cells. This approach produced death specifically in Pkd1 mutant epithelial cells, with no effect on normal renal epithelial cells. Moreover, treatment with the Smac-mimetic slowed cyst and kidney enlargement and preserved renal function in two genetic strains of mice with Pkd1 mutations. Thus, our mechanistic data characterize an apoptotic pathway, activated by the selective synergy of an Smac-mimetic and TNF-α in renal cyst fluid, that attenuates cyst development, providing an innovative translational platform for the rational development of novel therapeutics for ADPKD.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Transporte/fisiologia , Dipeptídeos/farmacologia , Células Epiteliais/efeitos dos fármacos , Indóis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas Mitocondriais/fisiologia , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/patologia , Animais , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Células Cultivadas , Células Epiteliais/citologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Túbulos Renais Proximais/citologia , Camundongos , Camundongos Mutantes , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/genética , NF-kappa B/metabolismo , Rim Policístico Autossômico Dominante/genética , Gravidez , Canais de Cátion TRPP/genética , Fator de Necrose Tumoral alfa/fisiologia
12.
Pediatr Transplant ; 17(4): 328-35, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23593929

RESUMO

Improved neonatal medical care and renal replacement technology have improved the long-term survival of patients with ARPKD. Ten-yr survival of those surviving the first year of life is reported to be 82% and is continuing to improve further. However, despite increases in overall survival and improved treatment of systemic hypertension and other complications of their renal disease, nearly 50% of survivors will develop ESRD within the first decade of life. In addition to renal pathology, patients with ARPKD develop ductal plate malformations with cystic dilation of intra- and extrahepatic bile ducts resulting in CHF and Caroli syndrome. Many patients with CHF will develop portal hypertension with resulting esophageal varices, splenomegaly, hypersplenism, protein losing enteropathy, and gastrointestinal bleeding. Management of portal hypertension may require EBL of esophageal varices or porto-systemic shunting. Complications of hepatic involvement can include ascending cholangitis, cholestasis with malabsorption of fat-soluble vitamins, and rarely benign or malignant liver tumors. Patients with ARPKD who eventually reach ESRD, and ultimately require kidney transplantation, present a unique set of complications related to their underlying hepato-biliary disease. In this review, we focus on new approaches to these challenging patients, including the indications for liver transplantation in ARPKD patients with severe chronic kidney disease awaiting kidney transplant. While survival in patients with ARPKD and isolated kidney transplant is comparable to that of age-matched pediatric patients who have received kidney transplants due to other primary renal diseases, 64-80% of the mortality occurring in ARPKD kidney transplant patients is attributed to cholangitis/sepsis, which is related to their hepato-biliary disease. Recent data demonstrate that surgical mortality among pediatric liver transplant recipients is decreased to <10% at one yr. The immunosuppressive regimen used for kidney transplant recipients is adequate for most liver transplant recipients. We therefore suggest that in a select group of ARPKD patients with recurrent cholangitis or complications of portal hypertension, combined liver-kidney transplant is a viable option. Although further study is necessary to confirm our approach, we believe that combined liver-kidney transplantation can potentially decrease overall mortality and morbidity in carefully selected ARPKD patients with ESRD and clinically significant CHF.


Assuntos
Transplante de Rim/métodos , Transplante de Fígado/métodos , Rim Policístico Autossômico Recessivo/terapia , Doença de Caroli/complicações , Criança , Colangite/complicações , Colestase/complicações , Humanos , Hipertensão Portal/complicações , Imunossupressores/uso terapêutico , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Hepatopatias/complicações , Falência Hepática/complicações , Falência Hepática/terapia , Neoplasias Hepáticas/complicações , Seleção de Pacientes , Rim Policístico Autossômico Recessivo/complicações , Risco
13.
Cryo Letters ; 34(6): 608-18, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24441371

RESUMO

The long-term preservation of forest genetic resources is a vital part of preserving our forest crops for future generations. Unfortunately, there are few genebanks dedicated to forest trees and very few methods for long-term preservation of forest genetic resources collections aside from field plantings of a limited number of seed-derived or elite clonal individuals. The use of cryopreservation for the long-term storage of elite germplasm is increasingly being used for the long-term preservation of clonal agronomic crops but for forest trees, such as Eucalyptus, the methodology for cryopreservation of diverse genetic resources collections has not been established. We report the successful cryopreservation of a germplasm collection of in vitro shoot cultures of thirteen Eucalyptus spp. lines consisting of two E. grandis x E. camaldulensis lines, seven E. urophylla x E. grandis lines, one E. grandis line, two E. grandis x E. urophylla lines, and one E. camaldulensis line. In a comparison of two cryopreservation methods, sucrose sensitivity limited the application of encapsulation-dehydration. However, with droplet-vitrification, all thirteen lines had good survival after cryopreservation in liquid nitrogen. A 30 min exposure to Plant Vitrification Solution 2 (PVS2) yielded post-liquid nitrogen survival between 38% and 85% depending on the line. One hundred shoot tips from all thirteen lines are currently in long-term storage as a germplasm collection.


Assuntos
Criopreservação/métodos , Eucalyptus/fisiologia , Brotos de Planta/fisiologia , Crioprotetores/metabolismo , Dessecação , Eucalyptus/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Sacarose/metabolismo , Vitrificação
14.
West Indian Med J ; 62(3): 254-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24564049

RESUMO

Klippel-Trenaunay syndrome (KTS) is a rare congenital, vascular disorder affecting one or more limbs. The syndrome is characterized by capillary malformations, soft tissue or bony hypertrophy and varicose veins or venous malformations. We present a case of this disorder in a twelve-year old boy who had an enlarged right lower limb with varicosities. Investigations revealed extensive superficial and deep venous varices, with dilatation of the right common iliac and external iliac veins. Klippel-Trenaunay syndrome should be suspected in a child presenting with capillary haemangioma and an enlarged limb.


Assuntos
Síndrome de Klippel-Trenaunay-Weber/diagnóstico , Criança , Humanos , Masculino
15.
Physiol Genomics ; 44(15): 741-53, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22669842

RESUMO

Human data and animal models of autosomal recessive polycystic kidney disease (ARPKD) suggest that genetic factors modulate the onset and severity of the disease. We report here for the first time that ARPKD susceptibility is attenuated by introgressing the mutated Pkhd1 disease allele from the polycystic kidney (PCK) rat onto the FHH (Fawn-Hooded Hypertensive) genetic background. Compared with PCK, the FHH.Pkhd1 strain had significantly decreased renal cyst formation that coincided with a threefold reduction in mean kidney weights. Further analysis revealed that the FHH. Pkhd1 is protected from increased blood pressure as well as elevated plasma creatinine and blood urea nitrogen levels. On the other hand, liver weight and biliary cystogenesis revealed no differences between PCK and FHH.Pkdh1, indicating that genes within the FHH genetic background prevent the development of renal, but not hepatic, manifestations of ARPKD. Microarray expression analysis of kidneys from 30-day-old PCK rats revealed increased expression of genes previously identified in PKD renal expression profiles, such as inflammatory response, extracellular matrix synthesis, and cell proliferation genes among others, whereas the FHH.Pkhd1 did not show activation of these common markers of disease. This newly developed strain can serve as a tool to map modifier genes for renal disease in ARPKD and provides further insight into disease variability and pathophysiology.


Assuntos
Modelos Animais de Doenças , Genes Modificadores/genética , Rim Policístico Autossômico Recessivo/genética , Animais , Pressão Sanguínea , Regulação para Baixo/genética , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Humanos , Rim/metabolismo , Rim/patologia , Testes de Função Renal , Fígado/metabolismo , Fígado/patologia , Masculino , Mutação/genética , Análise de Sequência com Séries de Oligonucleotídeos , Tamanho do Órgão , Rim Policístico Autossômico Recessivo/fisiopatologia , Ratos , Receptores de Superfície Celular/genética , Software , Regulação para Cima/genética
16.
FASEB J ; 25(6): 1844-55, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21343176

RESUMO

The intracellular mechanisms underlying renal tubular epithelial cell proliferation and tubular repair following ischemia-reperfusion injury (IRI) remain poorly understood. In this report, we demonstrate that activator of G-protein signaling 3 (AGS3), an unconventional receptor-independent regulator of heterotrimeric G-protein function, influences renal tubular regeneration following IRI. In rat kidneys exposed to IRI, there was a temporal induction in renal AGS3 protein expression that peaked 72 h after reperfusion and corresponded to the repair and recovery phase following ischemic injury. Renal AGS3 expression was localized predominantly to the recovering outer medullary proximal tubular cells and was highly coexpressed with Ki-67, a marker of cell proliferation. Kidneys from mice deficient in the expression of AGS3 exhibited impaired renal tubular recovery 7 d following IRI compared to wild-type AGS3-expressing mice. Mechanistically, genetic knockdown of endogenous AGS3 mRNA and protein in renal tubular epithelial cells reduced cell proliferation in vitro. Similar reductions in renal tubular epithelial cell proliferation were observed following incubation with gallein, a selective inhibitor of Gßγ subunit activity, and lentiviral overexpression of the carboxyl-terminus of G-protein-coupled receptor kinase 2 (GRK2ct), a scavenger of Gßγ subunits. In summary, these data suggest that AGS3 acts through a novel receptor-independent mechanism to facilitate renal tubular epithelial cell proliferation and renal tubular regeneration.


Assuntos
Injúria Renal Aguda/metabolismo , Proteínas de Transporte/metabolismo , Túbulos Renais/fisiologia , Regeneração/fisiologia , Traumatismo por Reperfusão/metabolismo , Injúria Renal Aguda/patologia , Animais , Proteínas de Transporte/genética , Regulação da Expressão Gênica , Genótipo , Inibidores de Dissociação do Nucleotídeo Guanina , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/genética , Fatores de Tempo
17.
Pediatr Nephrol ; 26(5): 675-92, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21046169

RESUMO

A number of syndromic disorders have renal cysts as a component of their phenotypes. These disorders can generally be distinguished from autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) by imaging studies of their characteristic, predominantly non-renal associated abnormalities. Therefore, a major distinction in the differential diagnosis of enlarge echogenic kidneys is delineating ARPKD from ADPKD. ADPKD and ARPKD can be diagnosed by imaging the kidney with ultrasound, computed tomography, or magnetic resonance imaging (MRI), although ultrasound is still the method of choice for diagnosis in utero and in young children due to ease of use, cost, and safety. Differences in ultrasound characteristics, the presence or absence of associated extrarenal abnormalities, and the screening of the parents >40 years of age usually allow the clinician to make an accurate diagnosis. Early diagnosis of ADPKD and ARPKD affords the opportunity for maximal anticipatory care (i.e. blood pressure control) and in the not-too-distant future, the opportunity to benefit from new therapies currently being developed. If results are equivocal, genetic testing is available for both ARPKD and ADPKD. Specialized centers are now offering preimplantation genetic diagnosis and in vitro fertilization for parents who have previously had a child with ARPKD. For ADPKD patients, a number of therapeutic interventions are currently in clinical trial and may soon be available.


Assuntos
Doenças Renais Policísticas/diagnóstico , Doenças Renais Policísticas/terapia , Criança , Diagnóstico Precoce , Humanos
18.
Scand J Med Sci Sports ; 21(6): e1-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20561272

RESUMO

Exercise increases the synthesis of collagen in the extracellular matrix of skeletal muscle. Breakdown of skeletal muscle collagen has not yet been determined because of technical limitations. The purpose of the present study was to use local sampling to determine skeletal muscle collagen breakdown. Microdialysis fibers were tested in vitro to predict bath hydroxyproline (OHP) concentrations. We used an N-methyl-N-[tert-butyldimethyl-silyl]trifluoroacetimide derivative to analyze OHP using gas chromatography-mass spectroscopy (GC-MS) and compared the results with a colorimetric OHP assay. Ten young, healthy male subjects performed a bout of resistance exercise with one leg, followed 17-21 h later by in vivo skeletal muscle sampling by microdialysis in exercised (EX) and control (CON) legs. Microdialysis reliably predicted [OHP] in vitro (R(2)=0.90). Analysis with GC-MS was strongly correlated to traditional analysis methods (CON: slope=1.03, R(2)=0.896, and P<0.05, EX: slope=0.795, R(2)=0.896, and P<0.05). We conclude that in vitro, microdialysis fibers were able to measure OHP concentrations and were sensitive to changes in concentrations, a strenuous bout of exercise did not increase skeletal muscle collagen breakdown 17-21 h post-exercise, and our measurement of OHP using GC-MS was in agreement with traditional assays.


Assuntos
Colágeno/metabolismo , Microdiálise , Fibras Musculares Esqueléticas/metabolismo , Adolescente , Adulto , Colágeno/análise , Dinamarca , Teste de Esforço , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidroxiprolina/análise , Masculino , Adulto Jovem
19.
J Comput Chem ; 31(7): 1486-94, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20017163

RESUMO

A method for improved representation of electronic charge and spin densities for molecular and solid state systems is presented, based upon extensions of least squares fits to quantum mechanical "true" densities using basis functions of limited support. Attention is given to optimization of radial degrees of fit freedom, and the design of fit functions permitting rapid analytic manipulation and calculation of properties, such as Coulomb potentials. The method is demonstrated for covalent CO and for a large metal-organic crystalline structure.

20.
J Clin Microbiol ; 48(4): 1366-77, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20164282

RESUMO

Fluconazole in vitro susceptibility test results for 256,882 isolates of Candida spp. were collected from 142 sites in 41 countries from June 1997 to December 2007. Data were collected for 197,619 isolates tested with voriconazole from 2001 to 2007. A total of 31 different species of Candida were isolated. Increased rates of isolation of the common non-albicans species C. glabrata (10.2% to 11.7%), C. tropicalis (5.4% to 8.0%), and C. parapsilosis (4.8% to 5.6%) were noted when the time periods 1997 to 2000 and 2005 to 2007 were compared. Investigators tested clinical isolates of Candida spp. by the CLSI M44-A disk diffusion method. Overall, 90.2% of Candida isolates tested were susceptible (S) to fluconazole; however, 13 of 31 species identified exhibited decreased susceptibility (<75% S), similar to that seen with the resistant (R) species C. glabrata and C. krusei. Among 197,619 isolates of Candida spp. tested against voriconazole, 95.0% were S and 3% were R. About 30% of fluconazole-R isolates of C. albicans, C. glabrata, C. tropicalis, C. rugosa, C. lipolytica, C. pelliculosa, C. apicola, C. haemulonii, C. humicola, C. lambica, and C. ciferrii remained S to voriconazole. An increase in fluconazole resistance over time was seen with C. parapsilosis, C. guilliermondii, C. lusitaniae, C. sake, and C. pelliculosa. Among the emerging fluconazole-R species were C. guilliermondii (11.4% R), C. inconspicua (53.2% R), C. rugosa (41.8% R), and C. norvegensis (40.7% R). The rates of isolation of C. rugosa, C. inconspicua, and C. norvegensis increased by 5- to 10-fold over the 10.5-year study period. C. guilliermondii and C. rugosa were most prominent in Latin America, whereas C. inconspicua and C. norvegensis were most common in Eastern European countries. This survey identifies several less-common species of Candida with decreased susceptibility to azoles. These organisms may pose a future threat to optimal antifungal therapy and underscore the importance of prompt and accurate species identification and antifungal susceptibility testing.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Fluconazol/farmacologia , Pirimidinas/farmacologia , Triazóis/farmacologia , Candida/classificação , Candida/isolamento & purificação , Candidíase/microbiologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Voriconazol
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