Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Adv Rheumatol ; 64: 31, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1556787

RESUMO

Abstract Background To illustrate how (standardised) effect sizes (ES) vary based on calculation method and to provide considerations for improved reporting. Methods Data from three trials of tanezumab in subjects with osteoarthritis were analyzed. ES of tanezumab versus comparator for WOMAC Pain (outcome) was defined as least squares difference between means (mixed model for repeated measures analysis) divided by a pooled standard deviation (SD) of outcome scores. Three approaches to computing the SD were evaluated: Baseline (the pooled SD of WOMAC Pain values at baseline [pooled across treatments]); Endpoint (the pooled SD of these values at the time primary endpoints were assessed); and Median (the median pooled SD of these values based on the pooled SDs across available timepoints). Bootstrap analyses were used to compute 95% confidence intervals (CI). Results ES (95% CI) of tanezumab 2.5 mg based on Baseline, Endpoint, and Median SDs in one study were - 0.416 (- 0.796, - 0.060), - 0.195 (- 0.371, - 0.028), and - 0.196 (- 0.373, - 0.028), respectively; negative values indicate pain improvement. This pattern of ES differences (largest with Baseline SD, smallest with Endpoint SD, Median SD similar to Endpoint SD) was consistent across all studies and doses of tanezumab. Conclusion Differences in ES affect interpretation of treatment effect. Therefore, we advocate clearly reporting individual elements of ES in addition to its overall calculation. This is particularly important when ES estimates are used to determine sample sizes for clinical trials, as larger ES will lead to smaller sample sizes and potentially underpowered studies. Trial Registration Clinicaltrials.gov NCT02697773, NCT02709486, and NCT02528188.

2.
J. pediatr. (Rio J.) ; J. pediatr. (Rio J.);98(6): 548-550, Nov.-Dec. 2022.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1422008
3.
J Immunol ; 209(9): 1788-1795, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113884

RESUMO

Chronic lung allograft dysfunction is the major barrier to long-term survival in lung transplant recipients. Evidence supports type 1 alloimmunity as the predominant response in acute/chronic lung rejection, but the immunoregulatory mechanisms remain incompletely understood. We studied the combinatorial F-box E3 ligase system: F-box protein 3 (FBXO3; proinflammatory) and F-box and leucine-rich repeat protein 2 (FBXL2; anti-inflammatory and regulates TNFR-associated factor [TRAF] protein). Using the mouse orthotopic lung transplant model, we evaluated allografts from BALB/c → C57BL/6 (acute rejection; day 10) and found significant induction of FBXO3 and diminished FBXL2 protein along with elevated T-bet, IFN-γ, and TRAF proteins 1-5 compared with isografts. In the acute model, treatment with costimulation blockade (MR1/CTLA4-Ig) resulted in attenuated FBXO3, preserved FBXL2, and substantially reduced T-bet, IFN-γ, and TRAFs 1-5, consistent with a key role for type 1 alloimmunity. Immunohistochemistry revealed significant changes in the FBXO3/FBXL2 balance in airway epithelia and infiltrating mononuclear cells during rejection compared with isografts or costimulation blockade-treated allografts. In the chronic lung rejection model, DBA/2J/C57BL/6F1 > DBA/2J (day 28), we observed persistently elevated FBXO3/FBXL2 balance and T-bet/IFN-γ protein and similar findings from lung transplant recipient lungs with chronic lung allograft dysfunction versus controls. We hypothesized that FBXL2 regulated T-bet and found FBXL2 was sufficient to polyubiquitinate T-bet and coimmunoprecipitated with T-bet on pulldown experiments and vice versa in Jurkat cells. Transfection with FBXL2 diminished T-bet protein in a dose-dependent manner in mouse lung epithelial cells. In testing type 1 cytokines, TNF-α was found to negatively regulate FBXL2 protein and mRNA levels. Together, our findings show the combinatorial E3 ligase FBXO3/FBXL2 system plays a role in the regulation of T-bet through FBXL2, with negative cross-regulation of TNF-α on FBXL2 during lung allograft rejection.


Assuntos
Proteínas F-Box , Animais , Camundongos , Abatacepte , Aloenxertos , Citocinas/metabolismo , Modelos Animais de Doenças , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Rejeição de Enxerto , Pulmão/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , RNA Mensageiro , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
5.
BMC Evol Biol ; 20(1): 106, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811443

RESUMO

BACKGROUND: The Caribbean offers a unique opportunity to study evolutionary dynamics in insular mammals. However, the recent extinction of most Caribbean non-volant mammals has obstructed evolutionary studies, and poor DNA preservation associated with tropical environments means that very few ancient DNA sequences are available for extinct vertebrates known from the region's Holocene subfossil record. The endemic Caribbean eulipotyphlan family Nesophontidae ("island-shrews") became extinct ~ 500 years ago, and the taxonomic validity of many Nesophontes species and their wider evolutionary dynamics remain unclear. Here we use both morphometric and palaeogenomic methods to clarify the status and evolutionary history of Nesophontes species from Hispaniola, the second-largest Caribbean island. RESULTS: Principal component analysis of 65 Nesophontes mandibles from late Quaternary fossil sites across Hispaniola identified three non-overlapping morphometric clusters, providing statistical support for the existence of three size-differentiated Hispaniolan Nesophontes species. We were also able to extract and sequence ancient DNA from a ~ 750-year-old specimen of Nesophontes zamicrus, the smallest non-volant Caribbean mammal, including a whole-mitochondrial genome and partial nuclear genes. Nesophontes paramicrus (39-47 g) and N. zamicrus (~ 10 g) diverged recently during the Middle Pleistocene (mean estimated divergence = 0.699 Ma), comparable to the youngest species splits in Eulipotyphla and other mammal groups. Pairwise genetic distance values for N. paramicrus and N. zamicrus based on mitochondrial and nuclear genes are low, but fall within the range of comparative pairwise data for extant eulipotyphlan species-pairs. CONCLUSIONS: Our combined morphometric and palaeogenomic analyses provide evidence for multiple co-occurring species and rapid body size evolution in Hispaniolan Nesophontes, in contrast to patterns of genetic and morphometric differentiation seen in Hispaniola's extant non-volant land mammals. Different components of Hispaniola's mammal fauna have therefore exhibited drastically different rates of morphological evolution. Morphological evolution in Nesophontes is also rapid compared to patterns across the Eulipotyphla, and our study provides an important new example of rapid body size change in a small-bodied insular vertebrate lineage. The Caribbean was a hotspot for evolutionary diversification as well as preserving ancient biodiversity, and studying the surviving representatives of its mammal fauna is insufficient to reveal the evolutionary patterns and processes that generated regional diversity.


Assuntos
Tamanho Corporal , Fósseis , Musaranhos/classificação , Animais , DNA Antigo/análise , Filogenia , Índias Ocidentais
6.
J Parasitol Res ; 2019: 7409076, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275627

RESUMO

The pathological agents Toxoplasma gondii, Ancylostoma caninum, and Toxocara canis are widely distributed zoonotic parasites with high prevalence in tropical and subtropical regions of the world. The aim of the present study was to determine the presence of DNA from these parasites in sand samples from the sand playgrounds in the southeastern region of Mexico. Samples of sand were collected from 68 playgrounds in public parks in the city of Merida, Yucatan, which is the main urban area in the southeast of Mexico. The samples were examined using nested PCR to detect the SAG1 gene from Toxoplasma gondii, and endpoint PCR for the amplification of ITS-2 and rRNA-ITS2 genes from Toxocara canis and Ancylostoma caninum, respectively. The presence of T. gondii DNA was detected in 11.8% (8/68) samples, DNA from A. caninum and T. canis was not detected. Results indicate that playgrounds from the studied sandboxes are contaminated with T. gondii oocysts and may represent a risk of infection for people in contact with the sand, especially for preschoolers.

7.
Diabetes ; 67(7): 1369-1379, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29643061

RESUMO

Type 2 diabetes is associated with impaired exercise capacity. Alterations in both muscle perfusion and mitochondrial function can contribute to exercise impairment. We hypothesized that impaired muscle mitochondrial function in type 2 diabetes is mediated, in part, by decreased tissue oxygen delivery and would improve with oxygen supplementation. Ex vivo muscle mitochondrial content and respiration assessed from biopsy samples demonstrated expected differences in obese individuals with (n = 18) and without (n = 17) diabetes. Similarly, in vivo mitochondrial oxidative phosphorylation capacity measured in the gastrocnemius muscle via 31P-MRS indicated an impairment in the rate of ADP depletion with rest (27 ± 6 s [diabetes], 21 ± 7 s [control subjects]; P = 0.008) and oxidative phosphorylation (P = 0.046) in type 2 diabetes after isometric calf exercise compared with control subjects. Importantly, the in vivo impairment in oxidative capacity resolved with oxygen supplementation in adults with diabetes (ADP depletion rate 5.0 s faster, P = 0.012; oxidative phosphorylation 0.046 ± 0.079 mmol/L/s faster, P = 0.027). Multiple in vivo mitochondrial measures related to HbA1c These data suggest that oxygen availability is rate limiting for in vivo mitochondrial oxidative exercise recovery measured with 31P-MRS in individuals with uncomplicated diabetes. Targeting muscle oxygenation could improve exercise function in type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Mitocôndrias Musculares/efeitos dos fármacos , Obesidade/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Oxigênio/administração & dosagem , Adulto , Idoso , Respiração Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Obesidade/complicações , Obesidade/terapia , Oxigênio/farmacologia , Consumo de Oxigênio/fisiologia , Comportamento Sedentário
8.
Diabetes ; 64(2): 383-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25157095

RESUMO

Insulin resistance (IR) increases cardiovascular morbidity and is associated with mitochondrial dysfunction. IR is now recognized to be present in type 1 diabetes; however, its relationship with mitochondrial function is unknown. We determined the relationship between IR and muscle mitochondrial function in type 1 diabetes using the hyperinsulinemic-euglycemic clamp and (31)P-MRS before, during, and after near-maximal isometric calf exercise. Volunteers included 21 nonobese adolescents with type 1 diabetes and 17 nondiabetic control subjects with similar age, sex, BMI, Tanner stage, and activity levels. We found that youths with type 1 diabetes were more insulin resistant (median glucose infusion rate 10.1 vs. 18.9 mg/kglean/min; P < 0.0001) and had a longer time constant of the curve of ADP conversion to ATP (23.4 ± 5.3 vs. 18.8 ± 3.9 s, P < 0.001) and a lower rate of oxidative phosphorylation (median 0.09 vs. 0.21 mmol/L/s, P < 0.001). The ADP time constant (ß = -0.36, P = 0.026) and oxidative phosphorylation (ß = 0.02, P < 0.038) were related to IR but not HbA1c. Normal-weight youths with type 1 diabetes demonstrated slowed postexercise ATP resynthesis and were more insulin resistant than control subjects. The correlation between skeletal muscle mitochondrial dysfunction in type 1 diabetes and IR suggests a relationship between mitochondrial dysfunction and IR in type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Resistência à Insulina/fisiologia , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Adolescente , Criança , Feminino , Humanos , Masculino
9.
J Pediatr ; 165(3): 472-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24996986

RESUMO

OBJECTIVE: Neonatal abstinence syndrome (NAS) from in utero opioid exposure is highly variable with genetic factors appearing to play an important role. Epigenetic changes in cytosine:guanine (CpG) dinucleotide methylation can occur after drug exposure and may help to explain NAS variability. We correlated DNA methylation levels in the mu-opioid receptor (OPRM1) promoter in opioid-exposed infants with NAS outcomes. STUDY DESIGN: DNA samples from cord blood or saliva were analyzed for 86 infants who were being treated for NAS according to institutional protocol. Methylation levels at 16 OPRM1 CpG sites were determined and correlated with NAS outcome measures, including need for treatment, treatment with ≥ 2 medications, and length of hospital stay. We adjusted for covariates and multiple genetic testing. RESULTS: Sixty-five percent of infants required treatment for NAS, and 24% required ≥ 2 medications. Hypermethylation of the OPRM1 promoter was measured at the -10 CpG in treated vs nontreated infants (adjusted difference δ = 3.2% [95% CI, 0.3-6.0%], P = .03; nonsignificant after multiple testing correction). There was hypermethylation at the -14 (δ = 4.9% [95% CI, 1.8%-8.1%], P = .003), -10 (δ = 5.0% [95% CI, 2.3-7.7%], P = .0005), and +84 (δ = 3.5% [95% CI, 0.6-6.4], P = .02) CpG sites in infants requiring ≥ 2 medications, which remained significant for -14 and -10 after multiple testing correction. CONCLUSIONS: Increased methylation within the OPRM1 promoter is associated with worse NAS outcomes, consistent with gene silencing.


Assuntos
Epigênese Genética , Síndrome de Abstinência Neonatal/genética , Receptores Opioides mu/genética , Analgésicos Opioides/efeitos adversos , Metilação de DNA , Feminino , Humanos , Recém-Nascido , Troca Materno-Fetal , Gravidez , Regiões Promotoras Genéticas
10.
PLoS One ; 8(12): e81475, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24324696

RESUMO

The worldwide spread of diseases is considered a major threat to biodiversity and a possible driver of the decline of pollinator populations, particularly when novel species or strains of parasites emerge. Previous studies have suggested that populations of introduced European honeybee (Apis mellifera) and bumblebee species (Bombus terrestris and Bombus ruderatus) in Argentina share the neogregarine parasite Apicystis bombi with the native bumblebee (Bombus dahlbomii). In this study we investigated whether A. bombi is acting as an emergent parasite in the non-native populations. Specifically, we asked whether A. bombi, recently identified in Argentina, was introduced by European, non-native bees. Using ITS1 and ITS2 to assess the parasite's intraspecific genetic variation in bees from Argentina and Europe, we found a largely unstructured parasite population, with only 15% of the genetic variation being explained by geographic location. The most abundant haplotype in Argentina (found in all 9 specimens of non-native species) was identical to the most abundant haplotype in Europe (found in 6 out of 8 specimens). Similarly, there was no evidence of structuring by host species, with this factor explaining only 17% of the genetic variation. Interestingly, parasites in native Bombus ephippiatus from Mexico were genetically distant from the Argentine and European samples, suggesting that sufficient variability does exist in the ITS region to identify continent-level genetic structure in the parasite. Thus, the data suggest that A. bombi from Argentina and Europe share a common, relatively recent origin. Although our data did not provide information on the direction of transfer, the absence of genetic structure across space and host species suggests that A. bombi may be acting as an emergent infectious disease across bee taxa and continents.


Assuntos
Apicomplexa/genética , Abelhas/parasitologia , Variação Genética , Animais , Argentina , Evolução Biológica , Europa (Continente) , Geografia , Haplótipos/genética , Dados de Sequência Molecular , Especificidade da Espécie
11.
J Pediatr ; 162(5): 930-6.e1, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23260099

RESUMO

OBJECTIVES: To assess precision magnetic resonance imaging in the neonate and determine whether there is an early maternal influence on the pattern of neonatal fat deposition in the offspring of mothers with gestational diabetes mellitus (GDM) and obesity compared with the offspring of normal-weight women. STUDY DESIGN: A total of 25 neonates born to normal weight mothers (n = 13) and to obese mothers with GDM (n = 12) underwent magnetic resonance imaging for the measurement of subcutaneous and intra-abdominal fat and magnetic resonance spectroscopy for the measurement of intrahepatocellular lipid (IHCL) fat at 1-3 weeks of age. RESULTS: Infants born to obese/GDM mothers had a mean 68% increase in IHCL compared with infants born to normal-weight mothers. For all infants, IHCL correlated with maternal prepregnancy body mass index but not with subcutaneous adiposity. CONCLUSION: Deposition of liver fat in the neonate correlates highly with maternal body mass index. This finding may have implications for understanding the developmental origins of childhood nonalcoholic fatty liver disease.


Assuntos
Diabetes Gestacional/fisiopatologia , Fígado Gorduroso/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Obesidade/fisiopatologia , Adiposidade , Adulto , Composição Corporal , Fígado Gorduroso/complicações , Feminino , Humanos , Recém-Nascido , Masculino , Obesidade/complicações , Gravidez , Reprodutibilidade dos Testes , Fatores de Risco
12.
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA