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1.
J Nematol ; 54(1): 20220057, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36742266

RESUMO

Pratylenchus is one of the most limiting nematodes of Musaceae production in the world. Knowledge of the nematode species is one of the requirements for its management in the field. This study aimed to identify up to the species level Pratylenchus populations associated with plantain and banana crops in the states of Caldas, Quindío, and Valle del Cauca in Colombia. In these regions, Pratylenchus has been reported to affect these crops in the past, but with records of the nematode only up to the genus level. For this purpose, five populations of Pratylenchus extracted from samples composed of roots and rhizospheric soil, four from plantain and one from banana, were identified through morphological, morphometric, and molecular analysis (sequencing of the D2-D3 of rRNA and cytochrome oxidase subunit I of mtDNA). All populations were identified as P. araucensis, a species reported previously in eastern Colombia, and one that the present study found in the center and southwest of the country, indicating that this species of nematode is widely distributed in the Musaceae-producing areas of Colombia. The present study reports the first COI mtDNA sequences for this species of nematode.

2.
Diabet Med ; 37(12): 2124-2130, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31709648

RESUMO

AIMS: To examine whether the presence of two common missense variants in the CYP2C9 gene (rs1799853, encoding Arg144Cys and denoted as *2, and rs1057910, encoding Ile359Leu and denoted as *3) influences the acute physiological response to a single glipizide dose in individuals naïve to diabetes medications. METHODS: In the Study to Understand the Genetics of the Acute Response to Metformin and Glipizide in Humans (SUGAR-MGH), 786 individuals genotyped for rs1799853/rs41291560 (*2) and rs1057910/rs9332214 (*3) were treated with 5 mg glipizide in the fasting state. Glucose and insulin levels were measured at baseline, 30, 60, 90, 120, 180 and 240 min for calculation of phenotypic endpoints of glipizide response. The challenge was aborted as a result of hypoglycaemia, defined as glucose <2.8 mmol/l or hypoglycaemia-related symptoms. RESULTS: Carriers with two reduced function alleles had a 50% larger insulin area under the curve than carriers with zero or one copy (P=0.037), although this finding was primarily driven by an individual with a robust insulin response. In adjusted analyses, the risk of aborting the glipizide challenge was doubled in two-copy carriers (P=0.034). No significant findings were observed in glucose-based endpoints. CONCLUSIONS: Carriers of two reduced function alleles in CYP2C9 may experience an increased insulin response to glipizide and be predisposed to a higher risk of hypoglycaemia, although no effect of genotype was seen in glucose-based measurements. Further studies are needed to clarify the utility of CYP2C9 genotyping to guide sulfonylurea treatment.


Assuntos
Glicemia/metabolismo , Citocromo P-450 CYP2C9/genética , Glipizida/uso terapêutico , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/uso terapêutico , Insulina/metabolismo , Adulto , Feminino , Humanos , Hipoglicemia/genética , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Variantes Farmacogenômicos , Polimorfismo de Nucleotídeo Único
3.
Mol Ecol ; 26(3): 740-751, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27891694

RESUMO

Many aspects of blue whale biology are poorly understood. Some of the gaps in our knowledge, such as those regarding their basic taxonomy and seasonal movements, directly affect our ability to monitor and manage blue whale populations. As a step towards filling in some of these gaps, microsatellite and mtDNA sequence analyses were conducted on blue whale samples from the Southern Hemisphere, the eastern tropical Pacific (ETP) and the northeast Pacific. The results indicate that the ETP is differentially used by blue whales from the northern and southern eastern Pacific, with the former showing stronger affinity to the region off Central America known as the Costa Rican Dome, and the latter favouring the waters of Peru and Ecuador. Although the pattern of genetic variation throughout the Southern Hemisphere is compatible with the recently proposed subspecies status of Chilean blue whales, some discrepancies remain between catch lengths and lengths from aerial photography, and not all blue whales in Chilean waters can be assumed to be of this type. Also, the range of the proposed Chilean subspecies, which extends to the Galapagos region of the ETP, at least seasonally, perhaps should include the Costa Rican Dome and the eastern North Pacific as well.


Assuntos
Balaenoptera/genética , Variação Genética , Genética Populacional , Migração Animal , Animais , América Central , Chile , DNA Mitocondrial/genética , Equador , Repetições de Microssatélites , Oceano Pacífico , Peru
4.
Nanotechnology ; 28(13): 135102, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28266350

RESUMO

Nanocarrier systems are currently being developed for peptide, protein and gene delivery to protect them in the blood circulation and in the gastrointestinal tract. Polylactic acid (PLA) and poly(lactic-co-glycolic) acid (PLGA) nanoparticles loaded with a new antimicrobial GIBIM-P5S9K peptide were obtained by the double emulsion solvent extraction/evaporation method. PLA- and PLGA-NPs were spherical with sizes between 300 and 400 nm for PLA and 200 and 300 nm for PLGA and <0.3 polydispersity index as determined by dynamic light scattering and scanning electron microscopy), having the zeta potential of >20 mV. The peptide-loading efficiency of PLA-NP and PLGA-NPs was 75% and 55%, respectively. PLA- and PLGA-NPs released around 50% of this peptide over 8 h. In 10% human sera the size of peptide loaded PLA- and PLGA-NPs increased between 25.2% and 39.3%, the PDI changed from 3.2 to 5.1 and the surface charge from -7.15 to 14.6 mV. Both peptide loaded PLA- and PLGA-NPs at 0.5 µM peptide concentration inhibited the growth of Escherichia coli O157:H7 (E. coli O157:H7), methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas. aeruginosa (P. aeruginosa). In contrast, free peptide inhibited at 10 µM but did not inhibit at 0.5 and 1 µM. These PLA- and PLGA-NPs presented <10% hemolysis indicating that they are hemocompatible and promising for delivery and protection system of GIBIM-P5S9K peptide.


Assuntos
Anti-Infecciosos/farmacologia , Escherichia coli O157/efeitos dos fármacos , Ácido Láctico/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanopartículas/química , Peptídeos/farmacologia , Ácido Poliglicólico/química , Pseudomonas aeruginosa/efeitos dos fármacos , Sequência de Aminoácidos , Liberação Controlada de Fármacos , Hemólise/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Tamanho da Partícula , Peptídeos/química , Poliésteres/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Soro/metabolismo
5.
J Eur Acad Dermatol Venereol ; 31(3): 438-442, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27518480

RESUMO

OBJECTIVE: To determine survival of a cohort of patients with acral lentiginous melanoma (ALM), treated at the National Cancer Institute of Colombia, the largest referral hospital of the country. METHODS: All patients diagnosed with an invasive ALM between 2003 and 2009 at the Colombian National Cancer Institute were included for analyses and followed for vital status and date of death. Using Kaplan-Meier methods, overall survival at 1, 3 and 5 years post diagnosis was determined, and Cox proportional hazards models were constructed for the variables showing a significant effect on survival in univariate analyses. RESULTS: Overall survival of this cohort of 90 patients was 77% at 1 year, 59% at 3 years and 54% at 5 years after diagnosis. Females had a better prognosis in univariate analyses but this advantage disappeared in multivariate models. Clinical stage was a strong predictor of survival, in univariate and multivariate models, particularly among elderly patients. CONCLUSIONS: Prognosis of ALM in Colombia is relatively poor, particularly for patients with higher clinical stage. The large proportions of ALM diagnosed in stage III and IV explain the relatively poor survival, and illustrate the importance of improving prognosis by lowering stage at diagnosis through better education and early detection programmes.


Assuntos
Melanoma/mortalidade , Melanoma/patologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Colômbia/epidemiologia , Feminino , , Mãos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Fatores Sexuais , Taxa de Sobrevida
6.
J Clin Microbiol ; 52(7): 2698-701, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24829244

RESUMO

We describe a new, efficient, sensitive, and fast single-tube multiple-PCR protocol for the identification of the most clinically significant Staphylococcus spp. and the simultaneous detection of the methicillin and mupirocin resistance loci. The protocol identifies at the species level isolates belonging to S. aureus, S. epidermidis, S. haemolyticus, S. hominis, S. lugdunensis, and S. saprophyticus.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação , Staphylococcus/efeitos dos fármacos , Humanos , Meticilina/farmacologia , Técnicas de Diagnóstico Molecular , Mupirocina/farmacologia , Sensibilidade e Especificidade , Staphylococcus/isolamento & purificação , Fatores de Tempo
7.
Mol Ecol ; 23(24): 5998-6010, 2014 12.
Artigo em Inglês | MEDLINE | ID: mdl-25492593

RESUMO

Blue whales (Balaenoptera musculus) were among the most intensively exploited species of whales in the world. As a consequence of this intense exploitation, blue whale sightings off the coast of Chile were uncommon by the end of the 20th century. In 2004, a feeding and nursing ground was reported in southern Chile (SCh). With the aim to investigate the genetic identity and relationship of these Chilean blue whales to those in other Southern Hemisphere areas, 60 biopsy samples were collected from blue whales in SCh between 2003 and 2009. These samples were genotyped at seven microsatellite loci and the mitochondrial control region was sequenced, allowing us to identify 52 individuals. To investigate the genetic identity of this suspected remnant population, we compared these 52 individuals to blue whales from Antarctica (ANT, n = 96), Northern Chile (NCh, n = 19) and the eastern tropical Pacific (ETP, n = 31). No significant differentiation in haplotype frequencies (mtDNA) or among genotypes (nDNA) was found between SCh, NCh and ETP, while significant differences were found between those three areas and Antarctica for both the mitochondrial and microsatellite analyses. Our results suggest at least two breeding population units or subspecies exist, which is also supported by other lines of evidence such as morphometrics and acoustics. The lack of differences detected between SCh/NCh/ETP areas supports the hypothesis that eastern South Pacific blue whales are using the ETP area as a possible breeding area. Considering the small population sizes previously reported for the SCh area, additional conservation measures and monitoring of this population should be developed and prioritized.


Assuntos
Balaenoptera/genética , Genética Populacional , Migração Animal , Animais , Regiões Antárticas , Teorema de Bayes , Núcleo Celular/genética , Chile , Análise por Conglomerados , DNA Mitocondrial/genética , Feminino , Fluxo Gênico , Variação Genética , Genótipo , Haplótipos , Masculino , Repetições de Microssatélites , Oceano Pacífico , Análise de Sequência de DNA
8.
Nutr Metab Cardiovasc Dis ; 23(11): 1043-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24103803

RESUMO

BACKGROUND/AIMS: The development of type 2 diabetes (T2D) is influenced both by environmental and by genetic determinants. Obesity is an important risk factor for T2D, mostly mediated by obesity-related insulin resistance. Obesity and insulin resistance are also modulated by the genetic milieu; thus, genes affecting risk of obesity and insulin resistance might also modulate risk of T2D. Recently, 32 loci have been associated with body mass index (BMI) by genome-wide studies, including one locus on chromosome 16p11 containing the SH2B1 gene. Animal studies have suggested that SH2B1 is a physiological enhancer of the insulin receptor and humans with rare deletions or mutations at SH2B1 are obese with a disproportionately high insulin resistance. Thus, the role of SH2B1 in both obesity and insulin resistance makes it a strong candidate for T2D. However, published data on the role of SH2B1 variability on the risk for T2D are conflicting, ranging from no effect at all to a robust association. METHODS: The SH2B1 tag SNP rs4788102 (SNP, single nucleotide polymorphism) was genotyped in 6978 individuals from six studies for abnormal glucose homeostasis (AGH), including impaired fasting glucose, impaired glucose tolerance or T2D, from the GENetics of Type 2 Diabetes in Italy and the United States (GENIUS T2D) consortium. Data from these studies were then meta-analyzed, in a Bayesian fashion, with those from DIAGRAM+ (n = 47,117) and four other published studies (n = 39,448). RESULTS: Variability at the SH2B1 obesity locus was not associated with AGH either in the GENIUS consortium (overall odds ratio (OR) = 0.96; 0.89-1.04) or in the meta-analysis (OR = 1.01; 0.98-1.05). CONCLUSION: Our data exclude a role for the SH2B1 obesity locus in the modulation of AGH.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Medicina Baseada em Evidências , Loci Gênicos , Transtornos do Metabolismo de Glucose/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Estudos de Associação Genética , Transtornos do Metabolismo de Glucose/metabolismo , Humanos , Obesidade/metabolismo , População Branca
9.
Chaos ; 23(2): 023120, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23822485

RESUMO

We have studied a spontaneous self-organization dynamics in a closed, dissipative (in terms of guansine 5'-triphosphate energy dissipation), reaction-diffusion system of acentrosomal microtubules (those nucleated and organized in the absence of a microtubule-organizing centre) multitude constituted of straight and curved acentrosomal microtubules, in highly crowded conditions, in vitro. Our data give experimental evidence that cross-diffusion in conjunction with excluded volume is the underlying mechanism on basis of which acentrosomal microtubule multitudes of different morphologies (straight and curved) undergo a spatial-temporal demix. Demix is constituted of a bifurcation process, manifested as a slow isothermal spinodal decomposition, and a dissipative process of transient periodic spatio-temporal pattern formation. While spinodal decomposition is an energy independent process, transient periodic spatio-temporal pattern formation is accompanied by energy dissipative process. Accordingly, we have determined that the critical threshold for slow, isothermal spinodal decomposition is 1.0 ± 0.05 mg/ml of microtubule protein concentration. We also found that periodic spacing of transient periodic spatio-temporal patterns was, in the overall, increasing versus time. For illustration, we found that a periodic spacing of the same pattern was 0.375 ± 0.036 mm, at 36 °C, at 155th min, while it was 0.540 ± 0.041 mm at 31 °C, and at 275th min after microtubule assembly started. The lifetime of transient periodic spatio-temporal patterns spans from half an hour to two hours approximately. The emergence of conditions of macroscopic symmetry breaking (that occur due to cross-diffusion in conjunction with excluded volume) may have more general but critical importance in morphological pattern development in complex, dissipative, but open cellular systems.


Assuntos
Centrossomo/metabolismo , Microtúbulos/metabolismo , Modelos Biológicos , Análise Espaço-Temporal , Animais , Bovinos , Guanosina Trifosfato/metabolismo , Cinética , Proteínas dos Microtúbulos/metabolismo
10.
Diabetologia ; 55(2): 331-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22038522

RESUMO

AIMS/HYPOTHESIS: Common genetic variants have been associated with type 2 diabetes. We hypothesised that a subset of these variants may have different effects on the transition from normal fasting glucose (NFG) to impaired fasting glucose (IFG) than on that from IFG to diabetes. METHODS: We identified 16 type 2 diabetes risk variants from the Illumina Broad Candidate-gene Association Resource (CARe) array genotyped in 26,576 CARe participants. Participants were categorised at baseline as NFG, IFG or type 2 diabetic (n = 16,465, 8,017 or 2,291, respectively). Using Cox proportional hazards and likelihood ratio tests (LRTs), we compared rates of progression by genotype for 4,909 (NFG to IFG) and 1,518 (IFG to type 2 diabetes) individuals, respectively. We then performed multinomial regression analyses at baseline, comparing the risk of assignment to the NFG, IFG or diabetes groups by genotype. RESULTS: The rate of progression from NFG to IFG was significantly greater in participants carrying the risk allele at MTNR1B (p = 1 × 10(-4)), nominally greater at GCK and SLC30A8 (p < 0.05) and nominally smaller at IGF2BP2 (p = 0.01) than the rate of progression from IFG to diabetes by the LRT. Results of the baseline, multinomial regression model were consistent with these findings. CONCLUSIONS/INTERPRETATION: Common genetic risk variants at GCK, SLC30A8, IGF2BP2 and MTNR1B influence to different extents the development of IFG and the transition from IFG to type 2 diabetes. Our findings may have implications for understanding the genetic contribution of these variants to the development of IFG and type 2 diabetes.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Variação Genética , Adulto , Idoso , Glicemia/análise , Estudos de Coortes , Progressão da Doença , Jejum , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Modelos de Riscos Proporcionais , Análise de Regressão , Risco
11.
Diabetologia ; 55(11): 2970-84, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22893027

RESUMO

AIMS/HYPOTHESIS: Hyperglycaemia disproportionately affects African-Americans (AfAs). We tested the transferability of 18 single-nucleotide polymorphisms (SNPs) associated with glycaemic traits identified in European ancestry (EuA) populations in 5,984 non-diabetic AfAs. METHODS: We meta-analysed SNP associations with fasting glucose (FG) or insulin (FI) in AfAs from five cohorts in the Candidate Gene Association Resource. We: (1) calculated allele frequency differences, variations in linkage disequilibrium (LD), fixation indices (F(st)s) and integrated haplotype scores (iHSs); (2) tested EuA SNPs in AfAs; and (3) interrogated within ± 250 kb around each EuA SNP in AfAs. RESULTS: Allele frequency differences ranged from 0.6% to 54%. F(st) exceeded 0.15 at 6/16 loci, indicating modest population differentiation. All iHSs were <2, suggesting no recent positive selection. For 18 SNPs, all directions of effect were the same and 95% CIs of association overlapped when comparing EuA with AfA. For 17 of 18 loci, at least one SNP was nominally associated with FG in AfAs. Four loci were significantly associated with FG (GCK, p = 5.8 × 10(-8); MTNR1B, p = 8.5 × 10(-9); and FADS1, p = 2.2 × 10(-4)) or FI (GCKR, p = 5.9 × 10(-4)). At GCK and MTNR1B the EuA and AfA SNPs represented the same signal, while at FADS1, and GCKR, the EuA and best AfA SNPs were weakly correlated (r(2) <0.2), suggesting allelic heterogeneity for association with FG at these loci. CONCLUSIONS/INTERPRETATION: Few glycaemic SNPs showed strict evidence of transferability from EuA to AfAs. Four loci were significantly associated in both AfAs and those with EuA after accounting for varying LD across ancestral groups, with new signals emerging to aid fine-mapping.


Assuntos
Glicemia/genética , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/genética , Hiperglicemia/etnologia , Hiperglicemia/genética , Insulina/genética , Adulto , Negro ou Afro-Americano/genética , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Genéticas/estatística & dados numéricos , Dessaturase de Ácido Graxo Delta-5 , Feminino , Frequência do Gene , Predisposição Genética para Doença/etnologia , Predisposição Genética para Doença/genética , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Fatores de Risco , População Branca/genética , População Branca/estatística & dados numéricos , Adulto Jovem
12.
Diabet Med ; 29(12): 1579-88, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22443353

RESUMO

AIMS: Baseline adiponectin concentrations predict incident Type 2 diabetes mellitus in the Diabetes Prevention Program. We tested the hypothesis that common variants in the genes encoding adiponectin (ADIPOQ) and its receptors (ADIPOR1, ADIPOR2) would associate with circulating adiponectin concentrations and/or with diabetes incidence in the Diabetes Prevention Program population. METHODS: Seventy-seven tagging single-nucleotide polymorphisms (SNPs) in ADIPOQ (24), ADIPOR1 (22) and ADIPOR2 (31) were genotyped. Associations of SNPs with baseline adiponectin concentrations were evaluated using linear modelling. Associations of SNPs with diabetes incidence were evaluated using Cox proportional hazards modelling. RESULTS: Thirteen of 24 ADIPOQ SNPs were significantly associated with baseline adiponectin concentrations. Multivariable analysis including these 13 SNPs revealed strong independent contributions of rs17366568, rs1648707, rs17373414 and rs1403696 with adiponectin concentrations. However, no ADIPOQ SNPs were directly associated with diabetes incidence. Two ADIPOR1 SNPs (rs1342387 and rs12733285) were associated with ∼18% increased diabetes incidence for carriers of the minor allele without differences across treatment groups, and without any relationship with adiponectin concentrations. CONCLUSIONS: ADIPOQ SNPs are significantly associated with adiponectin concentrations in the Diabetes Prevention Program cohort. This observation extends prior observations from unselected populations of European descent into a broader multi-ethnic population, and confirms the relevance of these variants in an obese/dysglycaemic population. Despite the robust relationship between adiponectin concentrations and diabetes risk in this cohort, variants in ADIPOQ that relate to adiponectin concentrations do not relate to diabetes risk in this population. ADIPOR1 variants exerted significant effects on diabetes risk distinct from any effect of adiponectin concentrations.


Assuntos
Adiponectina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina , Obesidade/metabolismo , Receptores de Adiponectina/metabolismo , Adiponectina/genética , Alelos , Diabetes Mellitus Tipo 2/genética , Feminino , Variação Genética , Genótipo , Humanos , Incidência , Resistência à Insulina/genética , Masculino , Obesidade/genética , Polimorfismo de Nucleotídeo Único/genética , Modelos de Riscos Proporcionais , Receptores de Adiponectina/genética
13.
Diabetologia ; 54(10): 2570-4, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21779873

RESUMO

AIMS/HYPOTHESIS: Individuals with impaired glucose tolerance have increased proinsulin levels, despite normal glucose or C-peptide levels. In the Diabetes Prevention Program (DPP), increased proinsulin levels predicted type 2 diabetes and proinsulin levels were significantly reduced following treatment with metformin, lifestyle modification or troglitazone compared with placebo. Genetic and physiological studies suggest a role for the zinc transporter gene SLC30A8 in diabetes risk, possibly through effects on insulin-processing in beta cells. We hypothesised that the risk allele at the type 2 diabetes-associated missense polymorphism rs13266634 (R325W) in SLC30A8 would predict proinsulin levels in individuals at risk of type 2 diabetes and may modulate response to preventive interventions. METHODS: We genotyped rs13266634 in 3,007 DPP participants and examined its association with fasting proinsulin and fasting insulin at baseline and at 1 year post-intervention. RESULTS: We found that increasing dosage of the C risk allele at SLC30A8 rs13266634 was significantly associated with higher proinsulin levels at baseline (p = 0.002) after adjustment for baseline insulin. This supports the hypothesis that risk alleles at SLC30A8 mark individuals with insulin-processing defects. At the 1 year analysis, proinsulin levels decreased significantly in all groups receiving active intervention and were no longer associated with SLC30A8 genotype (p = 0.86) after adjustment for insulin at baseline and 1 year. We found no genotype × treatment interactions at 1 year. CONCLUSIONS/INTERPRETATION: In prediabetic individuals, genotype at SLC30A8 predicts baseline proinsulin levels independently of insulin levels, but does not predict proinsulin levels after amelioration of insulin sensitivity at 1 year.


Assuntos
Proteínas de Transporte de Cátions/genética , Cromanos/uso terapêutico , Diabetes Mellitus/sangue , Diabetes Mellitus/genética , Metformina/uso terapêutico , Polimorfismo Genético/genética , Proinsulina/sangue , Tiazolidinedionas/uso terapêutico , Adulto , Peptídeo C/sangue , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/terapia , Diabetes Mellitus Tipo 2/genética , Feminino , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Troglitazona , Transportador 8 de Zinco
14.
Diabetologia ; 54(3): 535-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21109996

RESUMO

AIM/HYPOTHESIS: Common variants in the transcription factor 7-like 2 (TCF7L2) gene have been associated with type 2 diabetes in adults. However, it is not known whether TCF7L2 variation increases the risk of early onset type 2 diabetes. Using a case-control design, we examined whether the reported variants [rs12255372 (T/G) and rs7903146 (T/C)] are associated with type 2 diabetes in SEARCH for Diabetes in Youth study participants. METHODS: Variants were genotyped in 694 non-Hispanic white (NHW) youth (86 cases, mean age 15.5 years, mean BMI 34.8; and 608 controls, mean age 14.4 years, mean BMI 22.3) and 545 African-American (AA) youth (154 cases, mean age 15.9, mean BMI 37; and 391 controls, mean age 14.8, mean BMI 23.8). Logistic regression adjusted for age, sex, BMI and West African ancestry. RESULTS: The association of the risk T allele with case/control status was different in AA and NHW youth (p = 0.025). Among AA youth, each copy of the T allele (rs7903146) was associated with a 1.97-fold (1.37, 2.82) increased odds for type 2 diabetes (p < 0.0001), after adjustment for age, sex, BMI and African ancestry. No significant association was detected in NHW youth (adjusted OR, 1.14; 0.73, 1.79). CONCLUSION/INTERPRETATION: TCF7L2 variation is associated with an increased risk of early-onset type 2 diabetes among AA youth, and the association appears to be stronger in AA than NHW youth. This suggests potential different contributions of genetic and environmental factors to early-onset type 2 diabetes by race.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Polimorfismo Genético/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Adolescente , Diabetes Mellitus Tipo 2/etnologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino
15.
Dev Neurosci ; 33(5): 442-50, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21865666

RESUMO

Individuals with Down syndrome (DS) present cognitive deficits that can be improved by early implementation of special care programs. However, they showed limited and temporary cognitive effects. We previously demonstrated that postnatal environmental enrichment (EE) improved clearly, though temporarily, the execution of visuospatial memory tasks in Ts65Dn mice, a DS model bearing a partial trisomy of murine chromosome 16; but in contrast to wild-type littermates, there was a lack of structural plasticity in pyramidal cell structure in the trisomic cerebral cortex. In the present study, we have investigated the impact of EE on the function of adenylyl cyclase and phospholipase C as a possible mechanism underlying the time-limited improvements observed. Basal production of cyclic adenosine monophosphate (cAMP) was not affected, but responses to GTPγS, isoprenaline, noradrenaline, SKF 38393 and forskolin were depressed in the Ts65Dn hippocampus. In EE conditions, cAMP accumulation was not significantly modified in control animals with respect to nonenriched controls. However, EE had a marked effect in Ts65Dn mice, in which cAMP production was significantly increased. Similarly, EE increased phospholipase C activity in Ts65Dn mice, in response to carbachol and calcium. We conclude that EE restores the G-protein-associated signal transduction systems that are altered in Ts65Dn mice.


Assuntos
Síndrome de Down/fisiopatologia , Meio Ambiente , Proteínas de Ligação ao GTP/metabolismo , Transdução de Sinais/fisiologia , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Agonistas alfa-Adrenérgicos/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Animais , Carbacol/farmacologia , Agonistas Colinérgicos/farmacologia , Colforsina/farmacologia , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Agonistas de Dopamina/farmacologia , Feminino , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Isoproterenol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Norepinefrina/farmacologia
16.
J Clin Microbiol ; 49(9): 3429-31, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21775551

RESUMO

We report a case of intravenous catheter-associated fungemia caused by the recently described species Candida mengyuniae, a yeast not previously associated with human disease. The infection occurred in an 89-year-old woman with pancreatic adenocarcinoma. Yeast isolates recovered from a catheter and blood were identified as C. mengyuniae by sequencing of the 18S, 5.8S internal transcribed spacer, and D1/D2 26S ribosomal DNA domains.


Assuntos
Candida/isolamento & purificação , Candidemia/diagnóstico , Infecções Relacionadas a Cateter/diagnóstico , Adenocarcinoma/complicações , Idoso de 80 Anos ou mais , Sangue/microbiologia , Candida/classificação , Candida/genética , Candidemia/microbiologia , Infecções Relacionadas a Cateter/microbiologia , Catéteres/microbiologia , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Feminino , Genes de RNAr , Humanos , Dados de Sequência Molecular , Neoplasias Pancreáticas/complicações , RNA Fúngico/genética , RNA Ribossômico/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA
17.
Clin Epigenetics ; 13(1): 99, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933144

RESUMO

BACKGROUND: A subset of individuals with type 1 diabetes mellitus (T1DM) are predisposed to developing diabetic kidney disease (DKD), the most common cause globally of end-stage kidney disease (ESKD). Emerging evidence suggests epigenetic changes in DNA methylation may have a causal role in both T1DM and DKD. The aim of this exploratory investigation was to assess differences in blood-derived DNA methylation patterns between individuals with T1DM-ESKD and individuals with long-duration T1DM but no evidence of kidney disease upon repeated testing to identify potential blood-based biomarkers. Blood-derived DNA from individuals (107 cases, 253 controls and 14 experimental controls) were bisulphite treated before DNA methylation patterns from both groups were generated and analysed using Illumina's Infinium MethylationEPIC BeadChip arrays (n = 862,927 sites). Differentially methylated CpG sites (dmCpGs) were identified (false discovery rate adjusted p ≤ × 10-8 and fold change ± 2) by comparing methylation levels between ESKD cases and T1DM controls at single site resolution. Gene annotation and functionality was investigated to enrich and rank methylated regions associated with ESKD in T1DM. RESULTS: Top-ranked genes within which several dmCpGs were located and supported by functional data with methylation look-ups in other cohorts include: AFF3, ARID5B, CUX1, ELMO1, FKBP5, HDAC4, ITGAL, LY9, PIM1, RUNX3, SEPTIN9 and UPF3A. Top-ranked enrichment pathways included pathways in cancer, TGF-ß signalling and Th17 cell differentiation. CONCLUSIONS: Epigenetic alterations provide a dynamic link between an individual's genetic background and their environmental exposures. This robust evaluation of DNA methylation in carefully phenotyped individuals has identified biomarkers associated with ESKD, revealing several genes and implicated key pathways associated with ESKD in individuals with T1DM.


Assuntos
Metilação de DNA/genética , Diabetes Mellitus Tipo 1/complicações , Nefropatias Diabéticas/complicações , Epigênese Genética/genética , Falência Renal Crônica/genética , Adulto , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/genética , Epigenômica/métodos , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/etiologia , Masculino
18.
J Clin Microbiol ; 48(1): 329-32, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19906900
19.
Diabetologia ; 52(4): 614-20, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19183934

RESUMO

AIMS/HYPOTHESIS: Common variants in the TCF7L2 gene are associated with type 2 diabetes via impaired insulin secretion. One hypothesis is that variation in TCF7L2 impairs insulin processing in the beta cell. In contrast, the association of related TCF7L2 polymorphisms with obesity is controversial in that it has only been shown in cohorts susceptible to ascertainment bias. We reproduced the association of diabetes-associated variants with proinsulin/insulin ratios, and also examined the association of a TCF7L2 haplotype with obesity in the Framingham Heart Study (FHS). METHODS: We genotyped the TCF7L2 single nucleotide polymorphisms rs7903146 and rs12255372 (previously associated with type 2 diabetes) and rs10885406 and rs7924080 (which tag haplotype A [HapA], a haplotype reported to be associated with obesity) in 2,512 FHS participants. We used age- and sex-adjusted linear mixed-effects models to test for association with glycaemic traits, proinsulin/insulin ratios and obesity measures. RESULTS: As expected, the T risk allele of rs7903146 was associated with higher fasting plasma glucose (p = 0.01). T/T homozygotes had a 23.5% increase in the proinsulin/insulin ratio (p = 1 x 10(-7)) compared with C/C homozygotes. There was no association of HapA with BMI (p = 0.98), waist circumference (p = 0.89), subcutaneous adipose tissue (p = 0.32) or visceral adipose tissue (p = 0.92). CONCLUSIONS/INTERPRETATION: We confirmed that the risk allele of rs7903146 is associated with hyperglycaemia and a higher proinsulin/insulin ratio. We did not detect any association of the TCF7L2 HapA with adiposity measures, suggesting that this may have been a spurious association from ascertainment bias, possibly induced by the evaluation of obesity in separate groups of glycaemic cases and controls.


Assuntos
Variação Genética , Insulina/sangue , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Proinsulina/sangue , Fatores de Transcrição TCF/genética , Idoso , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/genética , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Massachusetts , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Proinsulina/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição , Circunferência da Cintura
20.
Diabetologia ; 52(11): 2299-2305, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19727660

RESUMO

AIMS/HYPOTHESIS: Advances in type 2 diabetes genetics have raised hopes that genetic testing will improve disease prediction, prevention and treatment. Little is known about current physician and patient views regarding type 2 diabetes genetic testing. We hypothesised that physician and patient views would differ regarding the impact of genetic testing on motivation and adherence. METHODS: We surveyed a nationally representative sample of US primary care physicians and endocrinologists (n = 304), a random sample of non-diabetic primary care patients (n = 152) and patients enrolled in a diabetes pharmacogenetics study (n = 89). RESULTS: Physicians and patients favoured genetic testing for diabetes risk prediction (79% of physicians vs 80% of non-diabetic patients would be somewhat/very likely to order/request testing, p = 0.7). More patients than physicians (71% vs 23%, p < 0.01) indicated that a 'high risk' result would be very likely to improve motivation to adopt preventive lifestyle changes. Patients favoured genetic testing to guide therapy (78% of patients vs 48% of physicians very likely to request/recommend testing, p < 0.01) and reported that genetic testing would make them 'much more motivated' to adhere to medications (72% vs 18% of physicians, p < 0.01). Many physicians (39%) would be somewhat/very likely to order genetic testing before published evidence of clinical efficacy. CONCLUSIONS/INTERPRETATION: Despite the paucity of current data, physicians and patients reported high expectations that genetic testing would improve patient motivation to adopt key behaviours for the prevention or control of type 2 diabetes. This suggests the testable hypothesis that 'genetic' risk information might have greater value to motivate behaviour change compared with standard risk information.


Assuntos
Diabetes Mellitus Tipo 2/genética , Testes Genéticos/métodos , Médicos de Família/estatística & dados numéricos , Coleta de Dados , Bases de Dados Factuais , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/prevenção & controle , Genoma Humano , Humanos , Medicina , Motivação , Pacientes , Percepção , Farmacogenética/métodos , Valor Preditivo dos Testes , Privacidade , Prática Profissional/estatística & dados numéricos , Medição de Risco
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