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1.
Nature ; 608(7922): 287-292, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948709

RESUMO

Particle accelerators and storage rings have been transformative instruments of discovery, and, for many applications, innovations in particle-beam cooling have been a principal driver of that success1. Stochastic cooling (SC), one of the most important conceptual and technological advances in this area2-6, cools a beam through granular sampling and correction of its phase-space structure, thus bearing resemblance to a 'Maxwell's demon'. The extension of SC from the microwave regime up to optical frequencies and bandwidths has long been pursued, as it could increase the achievable cooling rates by three to four orders of magnitude and provide a powerful tool for future accelerators. First proposed nearly 30 years ago, optical stochastic cooling (OSC) replaces the conventional microwave elements of SC with optical-frequency analogues and is, in principle, compatible with any species of charged-particle beam7,8. Here we describe a demonstration of OSC in a proof-of-principle experiment at the Fermi National Accelerator Laboratory's Integrable Optics Test Accelerator9,10. The experiment used 100-MeV electrons and a non-amplified configuration of OSC with a radiation wavelength of 950 nm, and achieved strong, simultaneous cooling of the beam in all degrees of freedom. This realization of SC at optical frequencies serves as a foundation for more advanced experiments with high-gain optical amplification, and advances opportunities for future operational OSC systems with potential benefit to a broad user community in the accelerator-based sciences.

2.
Brain Inj ; 33(13-14): 1602-1614, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31476880

RESUMO

Background: Research has shown that number of and blast-related Traumatic Brain Injuries (TBI) are associated with higher levels of service-connected disability (SCD) among US veterans. This study builds and tests a prediction model of SCD based on combat and training exposures experienced during active military service.Methods: Based on 492 US service member and veteran data collected at four Department of Veterans Affairs (VA) sites, traditional and Machine Learning algorithms were used to identify a best set of predictors and model type for predicting %SCD ≥50, the cut-point that allows for veteran access to 0% co-pay for VA health-care services.Results: The final model of predicting %SCD ≥50 in veterans revealed that the best blast/injury exposure-related predictors while deployed or non-deployed were: 1) number of controlled detonations experienced, 2) total number of blast exposures (including controlled and uncontrolled), and 3) the total number of uncontrolled blast and impact exposures.Conclusions and Relevance: We found that the highest blast/injury exposure predictor of %SCD ≥50 was number of controlled detonations, followed by total blasts, controlled or uncontrolled, and occurring in deployment or non-deployment settings. Further research confirming repetitive controlled blast exposure as a mechanism of chronic brain insult should be considered.


Assuntos
Lesões Encefálicas Traumáticas/epidemiologia , Distúrbios de Guerra/epidemiologia , Pessoas com Deficiência , Militares , United States Department of Veterans Affairs/tendências , Veteranos , Adulto , Idoso , Traumatismos por Explosões/diagnóstico , Traumatismos por Explosões/epidemiologia , Traumatismos por Explosões/psicologia , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/psicologia , Estudos de Coortes , Distúrbios de Guerra/diagnóstico , Distúrbios de Guerra/psicologia , Pessoas com Deficiência/psicologia , Feminino , Previsões , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Militares/psicologia , Modelos Teóricos , Estados Unidos/epidemiologia , Veteranos/psicologia , Adulto Jovem
3.
Integr Comp Biol ; 59(4): 953-969, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30924869

RESUMO

As part of mitonuclear communication, retrograde and anterograde signaling helps maintain homeostasis under basal conditions. Basal conditions, however, vary across phylogeny. At the cell-level, some mitonuclear retrograde responses can be quantified by measuring the constitutive components of oxidative stress, the balance between reactive oxygen species (ROS) and antioxidants. ROS are metabolic by-products produced by the mitochondria that can damage macromolecules by structurally altering proteins and inducing mutations in DNA, among other processes. To combat accumulating damage, organisms have evolved endogenous antioxidants and can consume exogenous antioxidants to sequester ROS before they cause cellular damage. ROS are also considered to be regulated through a retrograde signaling cascade from the mitochondria to the nucleus. These cellular pathways may have implications at the whole-animal level as well. For example, birds have higher basal metabolic rates, higher blood glucose concentration, and longer lifespans than similar sized mammals, however, the literature is divergent on whether oxidative stress is higher in birds compared with mammals. Herein, we collected literature values for whole-animal metabolism of birds and mammals. Then, we collected cellular metabolic rate data from primary fibroblast cells isolated from birds and mammals and we collected blood from a phylogenetically diverse group of birds and mammals housed at zoos and measured several parameters of oxidative stress. Additionally, we reviewed the literature on basal-level oxidative stress parameters between mammals and birds. We found that mass-specific metabolic rates were higher in birds compared with mammals. Our laboratory results suggest that cellular basal metabolism, total antioxidant capacity, circulating lipid damage, and catalase activity were significantly lower in birds compared with mammals. We found no body-size correlation on cellular metabolism or oxidative stress. We also found that most oxidative stress parameters significantly correlate with increasing age in mammals, but not in birds; and that correlations with reported maximum lifespans show different results compared with correlations with known aged birds. Our literature review revealed that basal levels of oxidative stress measurements for birds were rare, which made it difficult to draw conclusions.


Assuntos
Metabolismo Basal/fisiologia , Aves/fisiologia , Fenômenos Fisiológicos Sanguíneos , Fibroblastos/metabolismo , Mamíferos/fisiologia , Estresse Oxidativo/fisiologia , Fatores Etários , Animais , Tamanho Corporal , Especificidade da Espécie
4.
Proc Natl Acad Sci U S A ; 116(6): 2130-2137, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30670643

RESUMO

Voluntary sustainability standards (VSS) are stakeholder-derived principles with measurable and enforceable criteria to promote sustainable production outcomes. While institutional commitments to use VSS to meet sustainable procurement policies have grown rapidly over the past decade, we still have relatively little understanding of the (i) direct environmental benefits of large-scale VSS adoption; (ii) potential perverse indirect impacts of adoption; and (iii) implementation pathways. Here, we illustrate and address these knowledge gaps using an ecosystem service modeling and scenario analysis of Bonsucro, the leading VSS for sugarcane. We find that global compliance with the Bonsucro environmental standards would reduce current sugarcane production area (-24%), net tonnage (-11%), irrigation water use (-65%), nutrient loading (-34%), and greenhouse gas emissions from cultivation (-51%). Under a scenario of doubled global sugarcane production, Bonsucro adoption would further limit water use and greenhouse gas emissions by preventing sugarcane expansion into water-stressed and high-carbon stock ecosystems. This outcome was achieved via expansion largely on existing agricultural lands. However, displacement of other crops could drive detrimental impacts from indirect land use. We find that over half of the potential direct environmental benefits of Bonsucro standards under the doubling scenario could be achieved by targeting adoption in just 10% of global sugarcane production areas. However, designing policy that generates the most environmentally beneficial Bonsucro adoption pathway requires a better understanding of the economic and social costs of VSS adoption. Finally, we suggest research directions to advance sustainable consumption and production.

5.
Meat Sci ; 145: 79-85, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29908446

RESUMO

The utility of Raman spectroscopic signatures of fresh pork loin (1 d & 15 d postmortem) in predicting fresh pork tenderness and slice shear force (SSF) was determined. Partial least square models showed that sensory tenderness and SSF are weakly correlated (R2 = 0.2). Raman spectral data were collected in 6 s using a portable Raman spectrometer (RS). A PLS regression model was developed to predict quantitatively the tenderness scores and SSF values from Raman spectral data, with very limited success. It was discovered that the prediction accuracies for day 15 post mortem samples are significantly greater than that for day 1 postmortem samples. Classification models were developed to predict tenderness at two ends of sensory quality as "poor" vs. "good". The accuracies of classification into different quality categories (1st to 4th percentile) are also greater for the day 15 postmortem samples for sensory tenderness (93.5% vs 76.3%) and SSF (92.8% vs 76.1%). RS has the potential to become a rapid on-line screening tool for the pork producers to quickly select meats with superior quality and/or cull poor quality to meet market demand/expectations.


Assuntos
Culinária , Análise de Alimentos/métodos , Carne Vermelha/análise , Análise Espectral Raman/métodos , Estresse Mecânico , Animais , Classificação , Humanos , Análise dos Mínimos Quadrados , Modelos Estatísticos , Reprodutibilidade dos Testes , Suínos , Paladar
6.
J Anim Sci ; 95(6): 2533-2546, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28727041

RESUMO

There is considerable evidence that the protein component of fresh pork makes a major contribution to tenderness. In particular, the proteomic profile can be linked to postmortem events including pH decline, tissue oxidation, and protein degradation. The objectives for this study were to determine differences in sarcoplasmic proteomes that contribute to tenderness variation in aged pork longissimus dorsi muscles (LM). A defined set of pork loins selected to be similar in pH, color, and lipid yet different in tenderness were used. Pork loins were assigned to tenderness groups based on their star probe values; a high star probe group (HSP; n=12 mean star probe 7.75 kg) and low star probe group (LPS; n=12 star probe 4.95 kg) Samples were selected for proteomic experiments based on star probe values, and selected samples were within specified ranges for ultimate pH (5.54-5.86), marbling score (1.0-3.0), and percent total lipid (1.61-3.37%). Two-dimensional difference in gel electrophoresis (2D-DIGE) and mass spectrometry were used to examine sarcoplasmic protein abundance and potential modifications. Proteins spots that were significantly different across groups were selected for identification. Results from 2D-DIGE showed that HSP samples had significantly more abundant metabolic, stress response, and regulatory proteins in the sarcoplasmic fraction compared with LSP samples. The stress response protein peroxiredoxin-2 was more abundant in HSP samples as determined by 2D-DIGE ( ≤ 0.01; 2 spots) and western blot assay ( = 0.02). Low star probe samples showed significantly more degradation of the structural protein desmin in 2D-DIGE ( < 0.01) and western blot assay ( < 0.01). These results demonstrate that extreme proteolytic differences influenced measured tenderness of LSP and HSP samples and that soluble desmin and peroxiredoxin-2 may be used as biomarkers to differentiate between tough and tender aged pork products.


Assuntos
Proteoma , Carne Vermelha/análise , Suínos/fisiologia , Sequência de Aminoácidos , Animais , Cor , Culinária , Desmina/metabolismo , Proteólise , Proteômica
7.
J Anim Sci ; 95(4): 1574-1586, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28464104

RESUMO

The objective of this study was to determine factors that influence tenderness independent of variation in pH, color, or marbling. To achieve the objective, 2 sample groups were chosen from a population of 159 pork loins aged 11 to 16 d. Predetermined ranges (ultimate pH, 5.54 to 5.86; marbling score, 1.0 to 3.0; percent total lipid, 1.61 to 3.37%) were defined for inclusion of individual loins in the study. The pork loins with the greatest ( = 12) and least ( = 12) Instron star probe values were assigned to 2 classification groups. The high star probe group had an average star probe that was 2.8 kg greater than the low star probe group (7.75 vs. 4.95 kg). Pork quality and sensory characteristics of pH, subjective and instrumental color values, cook loss, sensory tenderness, chewiness, juiciness, pork flavor, and off flavor were determined on fresh, never frozen pork chops. Lipid content, sarcomere length, myosin heavy-chain profile, and calpain autolysis were determined. Degradation of troponin-T, desmin, filamin, and titin were evaluated on the protein extracts from each sample. Pork loin pH, subjective color scores, Minolta L values, sarcomere length, and myosin heavy-chain composition were not different across groups. Chops from the low star probe group had a significantly greater marbling score (2.3 vs. 1.9) and lipid content (2.61 vs. 2.23%). Calpain-1 was completely autolyzed in both high and low star probe samples, demonstrating that calpain-1 potentially had been active in all samples. Low star probe whole-muscle protein extracts had more troponin-T ( < 0.01), desmin ( < 0.01), and filamin degradation ( < 0.01) than high star probe samples. Both classification groups showed degradation of titin. Remarkably, some high star probe samples still had observable intact bands of titin on SDS-PAGE gels. These results demonstrate that significant variation in instrumental tenderness is observed within a moderate pH range. Lipid content and proteolysis both appear to contribute to this variation.


Assuntos
Proteínas Musculares/metabolismo , Carne Vermelha/normas , Suínos/fisiologia , Animais , Calpaína/metabolismo , Cor , Culinária , Desmina/metabolismo , Proteínas Musculares/análise , Cadeias Pesadas de Miosina/metabolismo , Mudanças Depois da Morte , Proteólise , Carne Vermelha/análise , Sarcômeros/fisiologia , Paladar , Troponina T/metabolismo
8.
Bone Marrow Transplant ; 52(8): 1133-1137, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28319075

RESUMO

Autologous hematopoietic stem cell transplantation (aHSCT) is a promising therapy for multiple sclerosis (MS), which has mainly been used in adults. The purpose of this study was to investigate efficacy and adverse events of aHSCT in the treatment of children with MS using data from the European Society for Blood and Marrow Transplantation registry. Twenty-one patients with a median follow-up time of 2.8 years could be identified. PFS at 3 years was 100%, 16 patients improved in expanded disability status scale score and only 2 patients experienced a clinical relapse. The procedure was generally well tolerated and only two instances of severe transplant-related toxicity were recorded. There was no treatment-related mortality, although one patient needed intensive care. aHSCT may be a therapeutic option for children with disease that does not respond to standard care.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Esclerose Múltipla/terapia , Adolescente , Criança , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Sistema de Registros , Transplante Autólogo , Resultado do Tratamento
9.
Hear Res ; 349: 21-30, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27913314

RESUMO

Military Service Members are often exposed to high levels of occupational noise, solvents, and other exposures that can be damaging to the auditory system. Little is known about hearing loss and how it progresses in Veterans following military service. This epidemiology study is designed to evaluate and monitor a cohort of Veterans for 20 years or more to determine how hearing loss changes over time and how those changes are related to noise exposure and other ototoxic exposures encountered during military service. Data reported here are from baseline assessments of the first 100 study participants (84 males; 16 females; mean age 33.5 years; SD 8.8; range 21-58). Each participant was asked to complete a comprehensive audiologic examination and self-report questionnaires regarding sociodemographic characteristics, noise and solvent exposures, health conditions common among post-deployment Veterans, and the social and emotional consequences of hearing loss. For this relatively young cohort, 29% exhibited hearing loss, defined as average hearing threshold >20 dB HL in the conventional audiometric range. Forty-two percent exhibited hearing loss in the extended-high-frequency audiometric range using the same criterion (average hearing threshold >20 dB HL). Certain factors were found to be associated with poorer hearing in both conventional and extended-high-frequency ranges, including age, type of military branch, years of military service, number of military deployments, noise exposure, tinnitus, and a positive screen for post-traumatic stress disorder. Although the majority of participants had hearing within normal limits, 27% reported a self-perceived mild/moderate hearing handicap and 14% reported a significant handicap. Further research is needed to identify a cause for this discrepancy in audiologic results versus self-report. The information obtained from this longitudinal study could be used in future resource planning with the goal of preventing, as much as possible, the development of hearing loss during military service, and the exacerbation of prevalent hearing loss after military service and over Veterans' lifetimes.


Assuntos
Percepção Auditiva , Divórcio , Perda Auditiva Provocada por Ruído/psicologia , Ruído Ocupacional/efeitos adversos , Doenças Profissionais/psicologia , Exposição Ocupacional/efeitos adversos , Zumbido/psicologia , Veteranos/psicologia , Estimulação Acústica , Adulto , Audiometria de Tons Puros , Audiometria da Fala , Percepção Auditiva/efeitos dos fármacos , Limiar Auditivo , Avaliação da Deficiência , Feminino , Audição/efeitos dos fármacos , Perda Auditiva Provocada por Ruído/diagnóstico , Perda Auditiva Provocada por Ruído/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/diagnóstico , Doenças Profissionais/fisiopatologia , Prevalência , Fatores de Risco , Solventes/efeitos adversos , Percepção da Fala , Inquéritos e Questionários , Fatores de Tempo , Zumbido/diagnóstico , Zumbido/fisiopatologia , Estados Unidos/epidemiologia , Adulto Jovem
10.
Mar Pollut Bull ; 114(2): 952-961, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27866724

RESUMO

Spatial and temporal patterns of coastal microbial pollution are not well documented. Our study examined these patterns through measurements of fecal indicator bacteria (FIB), nutrients, and physiochemical parameters in Hilo Bay, Hawai'i, during high and low river flow. >40% of samples tested positive for the human-associated Bacteroides marker, with highest percentages near rivers. Other FIB were also higher near rivers, but only Clostridium perfringens concentrations were related to discharge. During storms, FIB concentrations were three times to an order of magnitude higher, and increased with decreasing salinity and water temperature, and increasing turbidity. These relationships and high spatial resolution data for these parameters were used to create Enterococcus spp. and C. perfringens maps that predicted exceedances with 64% and 95% accuracy, respectively. Mapping microbial pollution patterns and predicting exceedances is a valuable tool that can improve water quality monitoring and aid in visualizing FIB hotspots for management actions.


Assuntos
Monitoramento Ambiental , Estuários , Rios/microbiologia , Microbiologia da Água , Bactérias , Bacteroides , Enterococcus , Fezes/microbiologia , Havaí , Humanos , Salinidade , Qualidade da Água
11.
Bone Marrow Transplant ; 51(12): 1569-1572, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27694943

RESUMO

High-dose melphalan and autologous stem cell transplantation (HDM/ASCT) is widely used in immunoglobulin light chain (AL) amyloidosis, but the benefit is debated mainly because of the high treatment-related mortality (24% in a randomised study comparing HDM/ASCT with oral melphalan/dexamethasone). We report here on the long-term outcome of all patients treated with HDM/ASCT for AL amyloidosis in Sweden between 1994 and 2009. Seventy-two patients were treated at eight Swedish centres. Median follow-up was 67.5 months. At least partial response (organ or haematological) was seen in 64% of the patients. Median overall survival was 98 months or 8.2 years, with 5-year survival 63.9% and 10-year survival 43.4%. In patients with cardiac involvement or multiple organ involvement, survival was significantly shorter, median overall survival 49 and 56 months, respectively. All mortality within 100 days from ASCT was 12.5% for all patients and 17.2% in the patients with cardiac involvement. For patients treated in the earlier time period (1994-2001), 100-day mortality was 23.8% compared with 7.8% in the later period (2002-2009). In conclusion, long survival times can be achieved in patients with AL amyloidosis treated with HDM/ASCT, also in smaller centres. Early mortality is high, but with a decreasing trend over time.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Amiloidose de Cadeia Leve de Imunoglobulina/terapia , Melfalan/administração & dosagem , Adulto , Intervalo Livre de Doença , Feminino , Seguimentos , Cardiopatias , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/mortalidade , Amiloidose de Cadeia Leve de Imunoglobulina/patologia , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos , Taxa de Sobrevida , Suécia , Tempo para o Tratamento , Transplante Autólogo , Resultado do Tratamento
13.
Aquat Toxicol ; 169: 19-26, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26485527

RESUMO

Early-life stage fish can be more sensitive to toxicants than adults, so delineating mechanisms of perturbation of biological pathways by chemicals during this life stage is crucial. Whole-mount in situ hybridization (WISH) paired with quantitative real-time polymerase chain reaction (QPCR) assays can enhance pathway-based analyses through determination of specific tissues where changes in gene expression are occurring. While WISH has frequently been used in zebrafish (Danio rerio), this technology has not previously been applied to fathead minnows (Pimephales promelas), another well-established small fish model species. The objective of the present study was to adapt WISH to fathead minnow embryos and larvae, and use the approach to evaluate the effects of estrone, an environmentally-relevant estrogen receptor (ER) agonist. Embryos were exposed via the water to 0, 18 or 1800 ng estrone/L (0, 0.067 and 6.7nM) for 3 or 6 days in a solvent-free, flow-through test system. Relative transcript abundance of three estrogen-responsive genes, estrogen receptor-α (esr1), cytochrome P450-aromatase B (cyp19b), and vitellogenin (vtg) was examined in pooled whole embryos using QPCR, and the spatial distribution of up-regulated gene transcripts was examined in individual fish using WISH. After 3 days of exposure to 1800 ng estrone/L, esr1 and cyp19b were significantly up-regulated, while vtg mRNA expression was not affected. After 6 days of exposure to 1800 ng estrone/L, transcripts for all three genes were significantly up-regulated. Corresponding WISH assays revealed spatial distribution of esr1 and vtg in the liver region, an observation consistent with activation of the hepatic ER. This study clearly demonstrates the potential utility of WISH, in conjunction with QPCR, to examine the mechanistic basis of the effects of toxicants on early-life stage fathead minnows.


Assuntos
Cyprinidae/embriologia , Embrião não Mamífero/efeitos dos fármacos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Animais , Aromatase/genética , Aromatase/metabolismo , Bioensaio , Embrião não Mamífero/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios/genética , Estrogênios/metabolismo , Hibridização In Situ , Larva , Fígado/efeitos dos fármacos , Fígado/embriologia , Fígado/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima , Vitelogeninas/genética , Vitelogeninas/metabolismo
14.
Bone Marrow Transplant ; 50(2): 216-20, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25387098

RESUMO

Autologous haematopoietic SCT (AHSCT) is increasingly used to control severe and refractory autoimmune diseases (AD). Many patients are women of reproductive age with a potential desire for children. We present a multicentre retrospective analysis of pregnancy and childbirth in patients who underwent AHSCT for AD. The databases of the European Blood and Marrow Transplantation and University of Sao Paulo, Ribeirão Preto, Brazil were searched for female patients aged 18-50 years who had received AHSCT for AD between 1994-2011. In 324 adult female patients, 22 pregnancies were reported in 15 patients between 1997-2011. Indications for AHSCT included multiple sclerosis (n=7), systemic sclerosis (n=5), rheumatoid arthritis (n=1), juvenile idiopathic arthritis (n=1) and Takayasu disease (n=1). Of the 22 reported pregnancies, 20 followed natural conception. 15 pregnancies (68%) resulted in healthy life births, whereas 7 (32%) failed. Exacerbations of AD occurred in two patients during second pregnancies. No maternal mortality was associated with pregnancy or postpartum. There were no reports of congenital, developmental or any other disease in the children. This retrospective analysis confirms the possibility of pregnancy and childbirth following AHSCT for severe AD. The outcome of pregnancy is generally good and most led to the birth of a healthy child.


Assuntos
Bases de Dados Factuais , Transplante de Células-Tronco Hematopoéticas , Nascido Vivo , Complicações na Gravidez/terapia , Adolescente , Adulto , Autoenxertos , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos
15.
J Intern Med ; 275(1): 39-48, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24482829

RESUMO

OBJECTIVE: Simple methods for the evaluation of dynamic b-cell function in epidemiological and clinical studies of patients with type 2 diabetes (T2D) are needed. The aim of this study was to evaluate the dynamic beta-cell function in young patients with T2D with different disease durations and treatments. METHODS: Overall, 54 subjects with T2D from the Diabetes Incidence Study in Sweden (DISS) and 23 healthy control participants were included in this cross-sectional study. Beta-cell function was assessed by intravenous (i.v.) administration of arginine followed by i.v. glucose. The acute insulin and C-peptide responses to arginine (AIRarg and Ac-pepRarg, respectively) and to glucose (AIRglu and Ac-pepRglu, respectively)were estimated.Homeostasis model assessment of b-cell function(HOMA-b) andCpeptide assessments were also used for comparisons between patients with T2D and control participants. RESULTS: AIRarg and Ac-pepRarg, but not AIRglu and Ac-pepRglu, could differentiate between patients with different disease durations. AIRglu values were 89% (P < 0.001) lower and AIRarg values were 29% (P < 0.01) lower in patients with T2D compared with control participants. HOMA-b and fasting plasma C-peptide levels did not differ between the T2D and control groups. CONCLUSION: In young patients with T2D, the insulin secretory response to i.v. glucose is markedly attenuated, whereas i.v. arginine-stimulated insulin release is better preserved and can distinguish between patients with different disease duration and antidiabetic therapies. This suggests that the i.v. arginine stimulation test may provide an estimate of functional beta-cell reserve.


Assuntos
Arginina , Peptídeo C , Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina/metabolismo , Insulina , Administração Intravenosa , Adulto , Arginina/administração & dosagem , Arginina/análise , Arginina/metabolismo , Peptídeo C/sangue , Peptídeo C/metabolismo , Fenômenos Fisiológicos Celulares/efeitos dos fármacos , Estudos Transversais , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Glucose/administração & dosagem , Glucose/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Insulina/sangue , Insulina/metabolismo , Insulina/farmacologia , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
16.
Int J Clin Pract ; 68(6): 731-42, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24472109

RESUMO

AIMS: Standardise the injection technique with botulinum toxin type A (BoNT A) in the bladder of patients with overactive bladder (OAB) [idiopathic overactive bladder (iOAB) or neurogenic overactive bladder (nOAB) with urinary incontinence], using a literature review and a survey of an International expert panel. METHODS: PubMed literature searches of BoNT A in adults with iOAB/nOAB together with a survey of 13 experts from 10 countries. RESULTS: Data from 21 articles and completed questionnaires were collated. The procedure can be carried out in an out-/inpatient setting. Dose used in clinical studies vs. clinical practice was 300 and 200 U for nOAB and 200 and 100 U for iOAB. Recent studies have also demonstrated that there are no clinically relevant benefits between 100 and 150 U in iOAB or between 300 and 200 U in nOAB, though adverse effects are increased with higher doses. Usually, 30 sites for nOAB (range: 6.7-10 U/ml) and 20-30 sites for iOAB (range: 5-10 U/ml) are injected in clinical studies vs. 20-30 sites of 1 ml/injection for 200 U in nOAB and 10-20 sites of 0.5-1 ml/injection for 100 U in iOAB in clinical practice. BoNT A is usually injected directly into the detrusor, sparing the trigone. Flexible or rigid cystoscopes are used. The needle should be typically 22-27 gauge and 4 mm in length and should have a stopper to avoid any leakage or perforation of the bladder wall while ensuring a targeted injection. CONCLUSION: Based on the literature and survey analysis, recommendations are proposed for the standardisation of the injection procedure.


Assuntos
Administração Intravesical , Toxinas Botulínicas Tipo A/uso terapêutico , Fármacos Neuromusculares/uso terapêutico , Bexiga Urinaria Neurogênica/tratamento farmacológico , Bexiga Urinária Hiperativa/tratamento farmacológico , Bexiga Urinária , Incontinência Urinária/tratamento farmacológico , Toxinas Botulínicas Tipo A/administração & dosagem , Humanos , Fármacos Neuromusculares/administração & dosagem , Inquéritos e Questionários
17.
J Musculoskelet Neuronal Interact ; 13(3): 283-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23989249

RESUMO

OBJECTIVE: An experiment was conducted to determine if modifying habitual activities to involve mechanical loading from more diverse directions can enhance the growing skeleton. METHODS: Growing female C57BL/6J mice were housed individually for 3 months in enclosures designed to accentuate either non-linear locomotion (diverse-orientation loading) or linear locomotion (stereotypic-orientation loading) (n=10/cage type). Behavioral assessments were performed daily to quantify cage activity level. Following the experiment, trabecular and cortical bone structure in the humeral head and distal femoral metaphysis were analyzed with µCT. RESULTS: Throughout the experiment, groups did not differ in cage activity level. Yet, following the experiment, the proximal humeri of mice that experienced increased diverse-orientation loading had significantly greater trabecular bone volume fraction (p=0.004), greater cortical bone area (p=0.005), greater cortical area fraction (p=0.0007), and thicker cortices (p=0.002). No significant group differences were detected in the distal femoral metaphysis. CONCLUSIONS: Diverting habitual activities to entail loading from more diverse orientations can augment the growing mouse skeleton. This study suggests that low-intensity activities that produce loads from diverse directions may represent a viable alternative to vigorous, high-impact exercise as a means of benefiting skeletal health during growth.


Assuntos
Desenvolvimento Ósseo/fisiologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiologia , Atividade Motora/fisiologia , Suporte de Carga/fisiologia , Animais , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Condicionamento Físico Animal/métodos , Tomografia Computadorizada por Raios X
18.
Diabet Med ; 30(3): e123-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23157253

RESUMO

AIMS: The objective of this retrospective analysis of blood glucose values at a week-long residential summer camp for children with Type 1 diabetes was to provide experiential data to reinforce current summer camp guidelines and to determine if specific interventions implemented between 2009 and 2010 were effective in lowering average blood glucose among our campers without increasing risk of hypoglycaemia. METHODS: Blood glucose records were obtained from a random selection of children who attended six 1-week camp sessions, three each in 2009 and 2010. Five values per day: pre-meal breakfast, lunch and dinner, pre-evening snack and midnight values were analysed. RESULTS: A total of 13,267 blood glucose values were included. There were no severe hypoglycaemic episodes, seizures or need for full-dose glucagon or intravenous glucose in either year. Mean blood glucose was significantly lower in 2010 compared with 2009 (9.22 vs. 10.06 mmol/l, P < 0.001). Older age and camp year were associated with lower mean blood glucose, even when controlling for gender and duration of diabetes. CONCLUSIONS: This analysis is the largest so far conducted at a residential diabetes camp. Mean blood glucose levels were lower than other published studies. Although we cannot attribute a cause-and-effect relationship between our interventions and the improvement in blood glucose between 2009 and 2010, the use of pre-meal insulin bolus doses, low glycaemic meals and highlighting blood glucose levels in logs before being reviewed by endocrinologists are strongly encouraged. From this study we hope to establish benchmarks for comparison among camps and begin to identify best practices.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Adolescente , Acampamento , Criança , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Masculino , Estudos Retrospectivos
19.
Int J Oral Maxillofac Surg ; 40(12): 1441-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21764560

RESUMO

A case of osteomyelitis in a 71-year-old woman with paroxysmal nocturnal hemoglobinuria (PNH) is reported. Osteomyelitis of the jaw is a well known condition of the oral and maxillofacial region that may cause severe morbidity. It is well documented that vaso-occlusive crises in sickle cell anaemia, a hemolytic blood disorder, can make the jaw bone susceptible to osteomyelitis. The authors report a case proposing an association between PNH and osteomyelitis of the mandible.


Assuntos
Hemoglobinúria Paroxística/complicações , Doenças Mandibulares/etiologia , Osteomielite/etiologia , Idoso , Anti-Inflamatórios/uso terapêutico , Doença Crônica , Feminino , Seguimentos , Glucocorticoides/uso terapêutico , Humanos , Osteosclerose/etiologia , Prednisolona/uso terapêutico , Radiografia Panorâmica
20.
Curr Med Res Opin ; 27(2): 375-82, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21175373

RESUMO

OBJECTIVE: Overactive bladder (OAB) is a common condition whose prevalence increases with age. Antimuscarinic agents are the pharmacologic treatment of choice, but adverse events such as dry mouth may lead to early discontinuation. The purpose of this analysis was to compare the incidence and severity of dry mouth and other adverse events with solifenacin 5 mg/day and oxybutynin immediate release (IR) 15 mg/day in patients ≤ 65 years and >65 years in the Canadian VECTOR study (VEsicare in Comparison To Oxybutynin for oveRactive bladder patients). RESEARCH DESIGN AND METHODS: VECTOR was a randomized, multicentre, prospective, double-blind, double-dummy study in 132 subjects with ≥ 1 urgency episode per 24 h, with or without urgency incontinence, and ≥ 8 micturitions per 24 h for ≥ 3 months. After a 2-week washout, patients received solifenacin 5 mg once daily or oxybutynin IR 5 mg tid for 8 weeks. For the current post-hoc analysis, adverse events were evaluated in subgroups of patients ≤ 65 years and >65 years, using a full logistic regression model, multinomial logit regression model and reduced model. CLINICAL TRIAL REGISTRATION: NCT00431041. RESULTS: The incidence and severity of dry mouth and other adverse events with solifenacin were similar between younger and older patients. In both age subgroups, solifenacin 5 mg/day was associated with fewer episodes and lower severity of dry mouth, and a lower discontinuation rate, compared with oxybutynin IR 15 mg/day. CONCLUSIONS: Solifenacin 5 mg/day was better tolerated than oxybutynin IR 15 mg/day in younger (≤ 65 years) and older (> 65 years) subgroups. Solifenacin was equally well tolerated in both age subgroups. Limitations of the analysis were that the study was not preplanned to perform post-hoc subgroup analysis, patients knew that dry mouth was a primary outcome, and the study used fixed doses of each drug.


Assuntos
Quinuclidinas/administração & dosagem , Quinuclidinas/efeitos adversos , Tetra-Hidroisoquinolinas/administração & dosagem , Tetra-Hidroisoquinolinas/efeitos adversos , Bexiga Urinária Hiperativa/tratamento farmacológico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Canadá , Formas de Dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Antagonistas Muscarínicos/administração & dosagem , Antagonistas Muscarínicos/efeitos adversos , Succinato de Solifenacina , Adulto Jovem
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