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1.
Circulation ; 147(14): 1079-1096, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-37011073

RESUMO

BACKGROUND: Large-scale human and mechanistic mouse studies indicate a strong relationship between the microbiome-dependent metabolite trimethylamine N-oxide (TMAO) and several cardiometabolic diseases. This study aims to investigate the role of TMAO in the pathogenesis of abdominal aortic aneurysm (AAA) and target its parent microbes as a potential pharmacological intervention. METHODS: TMAO and choline metabolites were examined in plasma samples, with associated clinical data, from 2 independent patient cohorts (N=2129 total). Mice were fed a high-choline diet and underwent 2 murine AAA models, angiotensin II infusion in low-density lipoprotein receptor-deficient (Ldlr-/-) mice or topical porcine pancreatic elastase in C57BL/6J mice. Gut microbial production of TMAO was inhibited through broad-spectrum antibiotics, targeted inhibition of the gut microbial choline TMA lyase (CutC/D) with fluoromethylcholine, or the use of mice genetically deficient in flavin monooxygenase 3 (Fmo3-/-). Finally, RNA sequencing of in vitro human vascular smooth muscle cells and in vivo mouse aortas was used to investigate how TMAO affects AAA. RESULTS: Elevated TMAO was associated with increased AAA incidence and growth in both patient cohorts studied. Dietary choline supplementation augmented plasma TMAO and aortic diameter in both mouse models of AAA, which was suppressed with poorly absorbed oral broad-spectrum antibiotics. Treatment with fluoromethylcholine ablated TMAO production, attenuated choline-augmented aneurysm initiation, and halted progression of an established aneurysm model. In addition, Fmo3-/- mice had reduced plasma TMAO and aortic diameters and were protected from AAA rupture compared with wild-type mice. RNA sequencing and functional analyses revealed choline supplementation in mice or TMAO treatment of human vascular smooth muscle cells-augmented gene pathways associated with the endoplasmic reticulum stress response, specifically the endoplasmic reticulum stress kinase PERK. CONCLUSIONS: These results define a role for gut microbiota-generated TMAO in AAA formation through upregulation of endoplasmic reticulum stress-related pathways in the aortic wall. In addition, inhibition of microbiome-derived TMAO may serve as a novel therapeutic approach for AAA treatment where none currently exist.


Assuntos
Aneurisma da Aorta Abdominal , Microbioma Gastrointestinal , Humanos , Camundongos , Animais , Suínos , Camundongos Endogâmicos C57BL , Colina , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/prevenção & controle
2.
Edmonton; Obesity Canada; Version 2; Oct. 21, 2022. 28 p.
Não convencional em Inglês | BIGG | ID: biblio-1509679

RESUMO

Healthy eating is important for all Canadians, regardless of body size, weight or health condition. Key messages from Canada's Food Guide for Healthy Eating can be used as a foundation for nutrition and food-related education (Figure 1). Use evidence-based nutrition resources to give your patients nutrition and behaviour change advice that aligns with their values, preferences and social determinants of health. (Figure 1) There is no one-size-fits-all eating pattern for obesity management. Adults living with obesity may consider various nutrition intervention options that are client-centred and flexible. Evidence suggests this approach will better facilitate long-term adherence. (Table 1, Figure 2) Nutrition interventions for obesity management should focus on achieving health outcomes for chronic disease risk reduction and quality of life improvements, not just weight changes. 5 Table 2 outlines health-related outcomes to support patients/clients in obesity management. Nutrition interventions for obesity management should emphasize individualized eating patterns, food quality and a healthy relationship with food. Including mindfulness-based eating practices that may help lower food cravings, reduce reward-driven eating, improve body satisfaction and improve awareness of hunger and satiety. 6­11 Caloric restriction can achieve short-term reductions in weight (i.e.< 12 months) but has not shown to be sustainable long-term (i.e. > 12 months). Caloric restriction may affect neurobiological pathways that control appetite, hunger, cravings and body weight regulation that may result in increased food intake and weight gain.64-66 People living with obesity are at increased risk for micronutrient deficiencies including but not limited to vitamin D, vitamin B12 and iron deficiencies. Restrictive eating patterns and obesity treatments (e.g. medications, bariatric surgery) may also result in micronutrient deficiencies and malnutrition. Assessment including biochemical values can help inform recommendations for food intake, vitamin/mineral supplements, and possible drug-nutrient interactions. Collaborate care with a registered dietitian who has experience in obesity management and medical nutrition therapy. 12 Dietitians can support people living with obesity who also have other chronic diseases, malnutrition, food insecurity or disordered patterns of eating. Future research should use nutrition-related outcomes and health behaviours in addition to weight and body composition outcomes. Characterization of population sample collections should use the updated definition of obesity as a chronic, progressive and relapsing disease characterized by the presence of adiposity that impairs health and social well-being rather than BMI exclusively. Qualitative data is needed to understand the lived experience of people with obesity.


Assuntos
Humanos , Restrição Calórica , Programas de Redução de Peso , Manejo da Obesidade , Obesidade/dietoterapia , Pressão Arterial , Controle Glicêmico
3.
Crit Care ; 26(1): 283, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127715

RESUMO

BACKGROUND: This review has been developed following a panel discussion with an international group of experts in the care of patients with obesity in the critical care setting and focuses on current best practices in malnutrition screening and assessment, estimation of energy needs for patients with obesity, the risks and management of sarcopenic obesity, the value of tailored nutrition recommendations, and the emerging role of immunonutrition. Patients admitted to the intensive care unit (ICU) increasingly present with overweight and obesity that require individualized nutrition considerations due to underlying comorbidities, immunological factors such as inflammation, and changes in energy expenditure and other aspects of metabolism. While research continues to accumulate, important knowledge gaps persist in recognizing and managing the complex nutritional needs in ICU patients with obesity. Available malnutrition screening and assessment tools are limited in patients with obesity due to a lack of validation and heterogeneous factors impacting nutrition status in this population. Estimations of energy and protein demands are also complex in patients with obesity and may include estimations based upon ideal, actual, or adjusted body weight. Evidence is still sparse on the role of immunonutrition in patients with obesity, but the presence of inflammation that impacts immune function may suggest a role for these nutrients in hemodynamically stable ICU patients. Educational efforts are needed for all clinicians who care for complex cases of critically ill patients with obesity, with a focus on strategies for optimal nutrition and the consideration of issues such as weight stigma and bias impacting the delivery of care. CONCLUSIONS: Current nutritional strategies for these patients should be undertaken with a focus on individualized care that considers the whole person, including the possibility of preexisting comorbidities, altered metabolism, and chronic stigma, which may impact the provision of nutritional care. Additional research should focus on the applicability of current guidelines and evidence for nutrition therapy in populations with obesity, especially in the setting of critical illness.


Assuntos
Desnutrição , Terapia Nutricional , Cuidados Críticos , Estado Terminal/terapia , Humanos , Inflamação , Desnutrição/terapia , Estado Nutricional , Obesidade/complicações , Obesidade/terapia , Lacunas da Prática Profissional
4.
Am J Physiol Heart Circ Physiol ; 318(6): H1474-H1486, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32330092

RESUMO

The gut microbe-derived metabolite trimethylamine-N-oxide (TMAO) has recently been linked to cardiovascular disease (CVD) pathogenesis, prompting the development of therapeutic strategies to reduce TMAO. Previous work has shown that experimental alteration of circulating TMAO levels via dietary alterations or inhibition of the host TMAO producing enzyme flavin containing monooxygenase 3 (FMO3) is associated with reorganization of host cholesterol and bile acid metabolism in mice. In this work, we set out to understand whether recently developed nonlethal gut microbe-targeting small molecule choline trimethylamine (TMA) lyase inhibitors also alter host cholesterol and bile acid metabolism. Treatment of mice with the mechanism-based choline TMA lyase inhibitor, iodomethylcholine (IMC), increased fecal neutral sterol loss in the form of coprostanol, a bacteria metabolite of cholesterol. In parallel, IMC treatment resulted in marked reductions in the intestinal sterol transporter Niemann-pick C1-like 1 (NPC1L1) and reorganization of the gut microbial community, primarily reversing choline supplemented diet-induced changes. IMC also prevented diet-driven hepatic cholesterol accumulation, causing both upregulation of the host hepatic bile acid synthetic enzyme CYP7A1 and altering the expression of hepatic genes critical for bile acid feedback regulation. These studies suggest that the gut microbiota-driven TMAO pathway is closely linked to both microbe and host sterol and bile acid metabolism. Collectively, as gut microbe-targeting choline TMA lyase inhibitors move through the drug discovery pipeline from preclinical models to human studies, it will be important to understand how these drugs impact both microbe and host cholesterol and bile acid metabolism.NEW & NOTEWORTHY The gut microbe-dependent metabolite trimethylamine-N-oxide (TMAO) has been strongly associated with cardiovascular mortality, prompting drug discovery efforts to identify points of therapeutic intervention within the microbe host TMAO pathway. Recently, mechanism-based small molecule inhibitors of the major bacterial trimethylamine (TMA) lyase enzymes have been developed, and these drugs show efficacy as anti-atherothrombotic agents. The novel findings of this study are that small molecule TMA lyase inhibition results in beneficial reorganization of host cholesterol and bile acid metabolism. This study confirms previous observations that the gut microbial TMAO pathway is intimately linked to host cholesterol and bile acid metabolism and provides further rationale for the development of small molecule choline TMA lyase inhibitors for the treatment of cardiometabolic disorders.


Assuntos
Ácidos e Sais Biliares/metabolismo , Colesterol/metabolismo , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/metabolismo , Animais , Colina/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos
5.
J Dairy Sci ; 103(2): 1795-1806, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759612

RESUMO

Vitamin D is commonly supplemented to dairy cows as vitamin D3 to support calcium homeostasis and in times of low sunlight exposure. Vitamin D has beneficial immunomodulatory and anti-inflammatory properties. Serum 25-hydroxyvitamin D [25(OH)D] concentrations fluctuated during lactation, with the lowest concentrations measured in healthy cows within 7 d of calving. However, it is unknown if serum 25(OH)D concentrations measured during the previous lactation are associated with transition diseases or health risk factors in dairy cattle. We collected serum samples from 279 dairy cattle from 5 commercial dairy herds in Michigan at dry-off, close-up, and 2-10 d in milk (DIM). Vitamin D concentrations were determined by measuring serum 25(OH)D by radioimmunoassay. Total serum calcium was measured by colorimetric methods. Body condition scores (BCS) were assigned at the time of blood collection. Clinical disease incidence was monitored until 30 d postparturition. Separate bivariable logistic regression analyses were used to determine if serum 25(OH)D at dry-off, close-up, and 2-10 DIM was associated with various clinical diseases including mastitis, lameness, and uterine disorders (classified as metritis, retained placenta, or both) and increased urine ketone concentrations at P < 0.05. Among all significant bivariable analyses, multivariable logistic regression analyses were built to adjust for potential confounding variables including parity, BCS, season, and calcium. Receiver operator characteristic (ROC) curve analyses were used to determine optimal concentrations of serum 25(OH)D. We found that higher serum 25(OH)D concentrations at dry-off and close-up predicted increased urine ketone concentrations in early lactation, even after adjustment for confounders. Alternatively, we found that lower serum 25(OH)D at 2-10 DIM was associated with uterine diseases. Optimal concentrations for serum 25(OH)D at dry-off and close-up for lower risk of increased urine ketone concentrations were below 103.4 and 91.1 ng/mL, respectively. The optimal concentration for serum 25(OH)D at 2-10 DIM for uterine diseases was above 71.4 ng/mL. These results indicate that serum 25(OH)D at dry-off and close-up may be a novel predictive biomarker for increased urine ketone concentrations during early lactation. Increased urine ketone concentrations are not necessarily harmful or diagnostic for ketosis but do indicate development of negative energy balance, metabolic stress, and increased risk of early lactation diseases. Predicting that dairy cattle are at increased risk of disease facilitates implementation of intervention strategies that may lower disease incidence. Future studies should confirm these findings and determine the utility of serum 25(OH)D concentrations as a predictive biomarker for clinical and subclinical ketosis.


Assuntos
Doenças dos Bovinos/sangue , Cetonas/urina , Cetose/veterinária , Vitamina D/sangue , Vitaminas/sangue , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/urina , Suplementos Nutricionais , Feminino , Cetose/sangue , Cetose/urina , Lactação , Michigan , Leite , Paridade , Período Pós-Parto , Gravidez , Fatores de Risco , Estações do Ano
6.
Toxicol In Vitro ; 62: 104680, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31626901

RESUMO

The U.S. Food and Drug Administration (FDA) Center for Devices and Radiological Health (CDRH) classifies personal lubricants as Class II medical devices. Because of this status and the nature of body contact common to personal lubricants, CDRH reviewers routinely recommend a standard biocompatibility testing battery that includes: an in vivo rabbit vaginal irritation (RVI) test; an in vivo skin sensitization test, such as the guinea pig maximization test (GPMT); and an in vivo acute systemic toxicity test using mice or rabbits. These tests are conducted using live animals, despite the availability of in vitro and other non-animal test methods that may be suitable replacements. The only test included in the biocompatibility battery currently conducted using in vitro assay(s) is cytotoxicity. FDA's recently launched Predictive Toxicology Roadmap calls for the optimization of non-animal methods for the safety evaluation of drugs, consumer products and medical devices. In line with these goals, a Consortium comprising the Institute for In Vitro Sciences, Inc. (IIVS), industry, the Consumer Healthcare Products Association (CHPA), and the PETA International Science Consortium (PETA-ISC) is qualifying the use of an in vitro testing method as replacement for the RVI test. Participating companies include manufacturers of personal lubricants and those interested in the advancement of non-animal approaches working collaboratively with the FDA CDRH to develop an in vitro testing approach that could be used in place of the RVI in pre-market submissions. Personal lubricants and vaginal moisturizers with diverse chemical and physical properties (e.g., formulation, viscosity, pH, and osmolality) in their final undiluted form will be the focus of the program. In vitro vaginal irritation data generated using commercially available human reconstructed vaginal tissue model(s) will be paired with existing in vivo RVI data and analyzed to develop a Prediction Model for the safety assessment of these products. This research plan has been accepted into the FDA CDRH Medical Device Development Tools (MDDT) program as a potential non-clinical assessment model (NAM). The proposed NAM aligns with the goals of the recently launched FDA Roadmap to integrate predictive toxicology methods into safety and risk assessment with the potential to replace or reduce the use of animal testing.


Assuntos
Alternativas aos Testes com Animais , Irritantes/toxicidade , Lubrificantes/toxicidade , Vaginite/induzido quimicamente , Animais , Avaliação Pré-Clínica de Medicamentos , Equipamentos e Provisões , Feminino , Humanos , Técnicas In Vitro , Modelos Biológicos , Valor Preditivo dos Testes , Medição de Risco , Estados Unidos , United States Food and Drug Administration , Vaginite/patologia
7.
J Food Prot ; 82(2): 287-300, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30682265

RESUMO

Temperature is arguably the most important factor affecting microbial proliferation in fresh-cut produce. In this study, growth of Listeria monocytogenes in diced onions and celery and Salmonella Typhimurium in diced tomatoes was determined in modified atmosphere packages and snap-fit containers using three fluctuating temperature scenarios for transport, retail storage, and display. As expected, L. monocytogenes growth in diced onions and celery varied depending on the extent of temperature abuse, with exposure to high and intermediate temperature-abuse scenarios generally being growth supportive. A Baranyi primary model with a square-root secondary model for maximum growth rate, and a linear model for maximum population density, were used to estimate Listeria growth under fluctuating temperature. Accuracy and acceptability of the model prediction were evaluated in terms of root mean square error (RMSE) and acceptable prediction zone (APZ), respectively. Overall, growth predictions for L. monocytogenes were more accurate for celery (RMSE, 0.28 to 0.47) than onions (RMSE, 0.42 to 1.53) under the fluctuating temperature scenarios tested. However, both predictions yielded APZ values that ranged from 82 to 100% for celery and 36 to 78% for onions. In contrast, Salmonella Typhimurium populations increased more than 1 log CFU/g in diced tomatoes under the three fluctuating temperature scenarios studied. Overall, these diced products packaged under a high-oxygen atmosphere showed decreased pathogen growth compared with product stored in a passive modified atmosphere. Findings from this study will be particularly useful in assessing the risk associated with consumption of diced celery, tomatoes, and onions and in designing effective packaging strategies to minimize pathogen growth in fresh-cut produce.


Assuntos
Apium , Manipulação de Alimentos , Listeria monocytogenes/crescimento & desenvolvimento , Cebolas , Salmonella typhimurium/crescimento & desenvolvimento , Solanum lycopersicum , Apium/microbiologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Solanum lycopersicum/microbiologia , Cebolas/microbiologia , Temperatura
8.
Eur J Cancer ; 94: 70-78, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29544162

RESUMO

The fracture impact of adjuvant bisphosphonates in breast cancer is not defined with most trials reporting changes in bone mineral density as a surrogate. The AZURE trial (ISRCTN79831382) evaluated the impact of adjuvant zoledronic acid (ZOL) on fractures. The AZURE trial is an academic, multi-centre, randomised phase III study evaluating the addition of ZOL 4 mg to standard therapy (neo/adjuvant chemotherapy and/or endocrine therapy) for 5 years (administered by intravenous (iv) infusion every 3-4 weeks for 6 doses, then 3 monthly × 8 and 6 monthly × 5) in patients with stage II/III early breast cancer. Fracture data collected as part of skeletal-related adverse event reporting were analysed after a median of 84.2 months of follow-up and 966 disease-free survival (DFS) events. We assessed number of fractures, time-to-first fracture and the incidence of fractures before and after disease recurrence. Two hundred forty-four patients reported ≥1 fracture, 140 (8.3%) in the control arm (171 fractures) and 104 (6.2%) in the ZOL arm (120 fractures). Of the 291 fractures reported, 207 fractures occurred in the absence of recurrence (control 111, ZOL 96), 80 after recurrence (control 59, ZOL 21). The 5-year fracture rate was reduced from 5.9% (95%CI 4.8, 7.1%; control) to 3.8% (95%CI 2.9, 4.7%) with ZOL. ZOL significantly increased time-to-first fracture (HR 0.69, 95%CI 0.53-0.90; P = 0.0053) but the majority of fracture prevention benefit occurred after a DFS event (HR 0.3; 95%CI 0.17, 0.53; P < 0.001). Fracture benefits from ZOL were similar across menopausal sub-groups. In conclusion, adjuvant ZOL reduced the risk of clinical fractures, the majority of this protection occurred after disease recurrence.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Neoplasias da Mama/complicações , Fraturas Ósseas/prevenção & controle , Ácido Zoledrônico/uso terapêutico , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Feminino , Fraturas Ósseas/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade
9.
Equine Vet J ; 49(6): 753-758, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28432750

RESUMO

BACKGROUND: Alpha-tocopherol (α-TP) supplementation is recommended for the prevention of various equine neuromuscular disorders. Formulations available include RRR-α-TP acetate powder and a more expensive but rapidly water-dispersible liquid RRR-α-TP (WD RRR-α-TP). No cost-effective means of rapidly increasing serum and cerebrospinal fluid (CSF) α-TP with WD RRR-α-TP and then sustaining concentrations with RRR-α-TP acetate has yet been reported. OBJECTIVES: To evaluate serum, CSF and muscle α-TP concentrations in an 8-week dosing regimen in which horses were transitioned from WD RRR-α-TP to RRR-α-TP acetate. STUDY DESIGN: Non-randomised controlled trial. METHODS: Healthy horses with serum α-TP of <2 µg/mL were divided into three groups and followed for 8 weeks. In the control group (n = 5), no α-TP was administered. In the second group (Group A; n = 7), 5000 IU/day RRR-α-TP acetate was administered. In the third group (Group WD-A; n = 7), doses of 5000 IU/day of WD RRR-α-TP were administered over 3 weeks, followed by a 4-week transition from WD RRR-α-TP to RRR-α-TP acetate, and a final 1 week of treatment with RRR-α-TP acetate. Serum samples were obtained weekly; muscle biopsies were obtained before, at 2.5 weeks and after supplementation. CSF samples were obtained before and after the 8-week period of supplementation. RESULTS: Serum α-TP increased significantly in Group WD-A at week 1 and remained significantly higher than in Group A and the control group throughout the transition, with inter-individual variation in response. Serum α-TP increased significantly by week 7 in Group A. CSF α-TP increased significantly in Group WD-A only. Muscle α-TP concentrations did not differ significantly across groups. Serum and CSF α-TP were closely correlated (r = 0.675), whereas serum and muscle-α-TP concentrations were not correlated. MAIN LIMITATIONS: The study duration was short and data on pre-transition CSF was lacking. CONCLUSIONS: The administration of 5000 IU/day of water-dispersible RRR-α-TP rapidly increases serum α-TP. Serum and CSF α-TP concentrations are sustained with a gradual transition to 5000 IU/day of RRR-α-TP acetate. Periodic evaluation of serum α-TP concentrations is recommended because responses vary among individuals.


Assuntos
Líquido Cefalorraquidiano/química , Doenças dos Cavalos/tratamento farmacológico , Músculo Esquelético/química , Deficiência de Vitamina E/veterinária , alfa-Tocoferol/uso terapêutico , Animais , Suplementos Nutricionais , Composição de Medicamentos , Feminino , Cavalos , Masculino , Projetos Piloto , Deficiência de Vitamina E/tratamento farmacológico , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/sangue , alfa-Tocoferol/líquido cefalorraquidiano
10.
Nat Methods ; 13(10): 883-889, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27617390

RESUMO

Phenotype-based small-molecule screening is a powerful method to identify molecules that regulate cellular functions. However, such screens are generally performed in vitro under conditions that do not necessarily model complex physiological conditions or disease states. Here, we use molecular cell barcoding to enable direct in vivo phenotypic screening of small-molecule libraries. The multiplexed nature of this approach allows rapid in vivo analysis of hundreds to thousands of compounds. Using this platform, we screened >700 covalent inhibitors directed toward hydrolases for their effect on pancreatic cancer metastatic seeding. We identified multiple hits and confirmed the relevant target of one compound as the lipase ABHD6. Pharmacological and genetic studies confirmed the role of this enzyme as a regulator of metastatic fitness. Our results highlight the applicability of this multiplexed screening platform for investigating complex processes in vivo.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Imagem Molecular/métodos , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Camundongos , Camundongos SCID , Monoacilglicerol Lipases/antagonistas & inibidores , Monoacilglicerol Lipases/genética , Transplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia
11.
Clin Cancer Res ; 22(13): 3138-47, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27154913

RESUMO

There is an urgent need to improve reproducibility and translatability of preclinical data to fully exploit opportunities for molecular therapeutics involving radiation and radiochemotherapy. For in vitro research, the clonogenic assay remains the current state-of-the-art of preclinical assays, whereas newer moderate and high-throughput assays offer the potential for rapid initial screening. Studies of radiation response modification by molecularly targeted agents can be improved using more physiologic 3D culture models. Elucidating effects on the cancer stem cells (CSC, and CSC-like) and developing biomarkers for defining targets and measuring responses are also important. In vivo studies are necessary to confirm in vitro findings, further define mechanism of action, and address immunomodulation and treatment-induced modification of the microenvironment. Newer in vivo models include genetically engineered and patient-derived xenograft mouse models and spontaneously occurring cancers in domesticated animals. Selection of appropriate endpoints is important for in vivo studies; for example, regrowth delay measures bulk tumor killing, whereas local tumor control assesses effects on CSCs. The reliability of individual assays requires standardization of procedures and cross-laboratory validation. Radiation modifiers must be tested as part of clinical standard of care, which includes radiochemotherapy for most tumors. Radiation models are compatible with but also differ from those used for drug screening. Furthermore, the mechanism of a drug as a chemotherapeutic agent may be different from its interaction with radiation and/or radiochemotherapy. This provides an opportunity to expand the use of molecular-targeted agents. Clin Cancer Res; 22(13); 3138-47. ©2016 AACR.


Assuntos
Antineoplásicos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Terapia de Alvo Molecular/métodos , Neoplasias/terapia , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/farmacologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células HeLa , Humanos , Camundongos , Neoplasias/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Reprodutibilidade dos Testes , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
12.
Phytopathology ; 106(2): 142-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26551449

RESUMO

The potato psyllid Bactericera cockerelli is implicated as the vector of the causal agent of zebra chip of potato and vein-greening of tomato diseases. Until now, visual identification of bacteria in the genus 'Candidatus Liberibacter' has relied on direct imaging by light and electron microscopy without labeling, or with whole-organ fluorescence labeling only. In this study, aldehyde fixative followed by a coagulant fixative, was used to process adult psyllids for transmission electron microscopy (TEM) colloidal gold in situ hybridization experiments. Results indicated that 'Ca. Liberibacter solanacearum' (CLso)-specific DNA probes annealed to a bacterium that formed extensive, monocultural biofilms on gut, salivary gland, and oral region tissues, confirming that it is one morphotype of potentially others, that is rod-shaped, approximately 2.5 µm in diameter and of variable length, and has a rough, granular cytosol. In addition, CLso, prepared from shredded midguts, and negatively stained for TEM, possessed pili- and flagella-like surface appendages. Genes implicating coding capacity for both types of surface structures are encoded in the CLso genome sequence. Neither type was seen for CLso associated with biofilms within or on digestive organs, suggesting that their production is stimulated only in certain environments, putatively, in the gut during adhesion leading to multiplication, and in hemolymph to afford systemic invasion.


Assuntos
Biofilmes , Hemípteros/microbiologia , Insetos Vetores/microbiologia , Doenças das Plantas/microbiologia , Rhizobiaceae/isolamento & purificação , Animais , Aderência Bacteriana , Sequência de Bases , Trato Gastrointestinal/microbiologia , Hemípteros/ultraestrutura , Hibridização in Situ Fluorescente , Insetos Vetores/ultraestrutura , Rhizobiaceae/genética , Rhizobiaceae/fisiologia , Rhizobiaceae/ultraestrutura , Glândulas Salivares/microbiologia , Solanum tuberosum/microbiologia
13.
Int J Radiat Oncol Biol Phys ; 92(3): 568-76, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26068491

RESUMO

Combining the latest targeted biologic agents with the most advanced radiation technologies has been an exciting development in the treatment of cancer patients. Stereotactic body radiation therapy (SBRT) is an ablative radiation approach that has become established for the treatment of a variety of malignancies, and it has been increasingly used in combination with biologic agents, including those targeting angiogenesis-specific pathways. Multiple reports have emerged describing unanticipated toxicities arising from the combination of SBRT and angiogenesis-targeting agents, particularly of late luminal gastrointestinal toxicities. In this review, we summarize the literature describing these toxicities, explore the biological mechanism of action of toxicity with the combined use of antiangiogenic therapies, and discuss areas of future research, so that this combination of treatment modalities can continue to be used in broader clinical contexts.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/efeitos da radiação , Neoplasias/terapia , Radiocirurgia/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Bevacizumab , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Humanos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/efeitos da radiação , Neovascularização Patológica/tratamento farmacológico , Niacinamida/efeitos adversos , Niacinamida/análogos & derivados , Órgãos em Risco , Compostos de Fenilureia/efeitos adversos , Sorafenibe , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/fisiologia
14.
J Musculoskelet Neuronal Interact ; 15(2): 145-53, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26032206

RESUMO

OBJECTIVES: We tested the hypothesis that daily vitD3 supplementation increases neuromuscular motor skills, jump power, jump energy, muscular force, and muscular strength. METHODS: This was a secondary analysis of a randomized controlled trial of 12-months of oral 7,000 IU/day vitD3 supplementation or placebo among 56 persons living with HIV aged 9-25 years. Neuromuscular motor skills were quantified using the Bruininks-Oseretsky Test of Motor Proficiency. Power was quantified using peak jump power, and energy was quantified using peak jump height. Muscular force was quantified using isometric ankle plantar- and dorsiflexion, isokinetic knee flexion and extension. Muscular strength was quantified using isometric handgrip strength. RESULTS: After 12-months, serum 25-hydroxyvitamin D [25(OH)D] was higher with supplementation versus placebo (ß=12.1 ng/mL; P<0.001). In intention-to-treat analyses, supplementation improved neuromuscular motor skills versus placebo (ß=1.14; P=0.041). We observed no effect of supplementation on jump power, jump energy, muscular force, or muscular strength outcomes versus placebo. CONCLUSIONS: Among HIV-infected children and young adults supplementation with daily high-dose vitD3 increased concentration of serum 25(OH)D and improved neuromuscular motor skills versus placebo.


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/fisiopatologia , Músculo Esquelético/fisiopatologia , Vitaminas/uso terapêutico , Adolescente , Criança , Pré-Escolar , Metabolismo Energético , Feminino , Força da Mão , Humanos , Contração Isométrica , Masculino , Destreza Motora , Força Muscular , Resultado do Tratamento , Adulto Jovem
15.
Transl Psychiatry ; 5: e569, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25989143

RESUMO

Considerable evidence implicates DISC1 as a susceptibility gene for multiple psychiatric diseases. DISC1 has been intensively studied at the molecular, cellular and behavioral level, but its role in regulating brain connectivity and brain network function remains unknown. Here, we utilize a set of complementary approaches to assess the functional brain network abnormalities present in mice expressing a truncated Disc1 gene (Disc1tr Hemi mice). Disc1tr Hemi mice exhibited hypometabolism in the prefrontal cortex (PFC) and reticular thalamus along with a reorganization of functional brain network connectivity that included compromised hippocampal-PFC connectivity. Altered hippocampal-PFC connectivity in Disc1tr Hemi mice was confirmed by electrophysiological analysis, with Disc1tr Hemi mice showing a reduced probability of presynaptic neurotransmitter release in the monosynaptic glutamatergic hippocampal CA1-PFC projection. Glutamate system dysfunction in Disc1tr Hemi mice was further supported by the attenuated cerebral metabolic response to the NMDA receptor (NMDAR) antagonist ketamine and decreased hippocampal expression of NMDAR subunits 2A and 2B in these animals. These data show that the Disc1 truncation in Disc1tr Hemi mice induces a range of translationally relevant endophenotypes underpinned by glutamate system dysfunction and altered brain connectivity.


Assuntos
Ácido Glutâmico/metabolismo , Hipocampo/fisiopatologia , Proteínas do Tecido Nervoso/genética , Córtex Pré-Frontal/fisiopatologia , Tálamo/fisiopatologia , Animais , Autorradiografia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/fisiopatologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/metabolismo , Ketamina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Técnicas de Patch-Clamp , Córtex Pré-Frontal/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transmissão Sináptica/fisiologia , Tálamo/metabolismo
16.
Talanta ; 129: 481-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25127622

RESUMO

A bioassay capable of monitoring occupational or environmental exposure to special nuclear materials would be a useful tool for nuclear nonproliferation programs. Hair and nail are potential biomonitors of exposure to U and Pu. A method is described to measure isotope ratios of ultra-trace concentrations of U and Pu in hair and nail samples. The method uses multiple extraction chromatography resins to separate U and Pu fractions from the sample matrix. The U recovery was quantitative while the Pu recovery ranged from 81% to 109%, with a U decontamination factor of 5×10(4). Following the separation (234)U/(238)U, (235)U/(238)U and (240)Pu/(239)Pu were measured in human hair and hair and nail samples using multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS). The human hair and nail samples had elevated ratios of (234)U/(238)U which could reflect exposure to naturally fractionated U.


Assuntos
Cromatografia/métodos , Cabelo/química , Espectrometria de Massas/métodos , Unhas/química , Plutônio/química , Urânio/química , Bioensaio , China , Exposição Ambiental/análise , Humanos , Limite de Detecção , Missouri , Reprodutibilidade dos Testes
17.
Osteoporos Int ; 25(7): 1821-30, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24519745

RESUMO

The purpose of this study was to investigate the impact of two educational interventions on the intake of calcium and vitamin D supplements and modifiable risk factors for osteoporosis in women ≥50 years with a fragility fracture (FF). Within 6-8 months of fracture, women were randomized to one of three intervention groups: usual care (UC), written materials (WM), or videocassette and written materials (VC). The written materials for patients and their physician provided information on osteoporosis, FF, and available treatments; written materials for physician were provided through patients. The videocassette presented similar information as the written material, but in greater depth. Twelve months after randomization, the effectiveness of the interventions was assessed. The study cohort consisted of 1,175 women undiagnosed and untreated for osteoporosis. After 12 months, the mean intake of Ca supplements increased by 33, 93, and 91 mg/day for the UC, WM, and VC groups, respectively (p value, WM vs UC = 0.163; VC vs UC = 0.026); the corresponding mean increases for vitamin D were 58, 105, and 118 IU/day (p value, WM vs UC = 0.214; VC vs UC = 0.012). The proportion of women who increased their Ca and vitamin D intake by supplements was similar in all three groups. The intervention had a greater impact in those not taking supplements at randomization and had no impact on modifiable risk factors. In women without diagnosis and treatment for osteoporosis, the interventions seem effective at increasing the amounts of Ca and vitamin D supplements, but not effective at inciting more women to increase their consumption. Therefore, the clinical significance of the impact of the intervention is difficult to evaluate.


Assuntos
Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Educação de Pacientes como Assunto/métodos , Idoso , Cálcio/administração & dosagem , Cálcio da Dieta/administração & dosagem , Suplementos Nutricionais , Uso de Medicamentos/estatística & dados numéricos , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Pessoa de Meia-Idade , Atividade Motora , Osteoporose Pós-Menopausa/complicações , Fraturas por Osteoporose/etiologia , Recidiva , Fatores de Risco , Gravação de Videoteipe , Vitamina D/administração & dosagem
18.
Nat Med ; 19(5): 576-85, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23563705

RESUMO

Intestinal microbiota metabolism of choline and phosphatidylcholine produces trimethylamine (TMA), which is further metabolized to a proatherogenic species, trimethylamine-N-oxide (TMAO). We demonstrate here that metabolism by intestinal microbiota of dietary L-carnitine, a trimethylamine abundant in red meat, also produces TMAO and accelerates atherosclerosis in mice. Omnivorous human subjects produced more TMAO than did vegans or vegetarians following ingestion of L-carnitine through a microbiota-dependent mechanism. The presence of specific bacterial taxa in human feces was associated with both plasma TMAO concentration and dietary status. Plasma L-carnitine levels in subjects undergoing cardiac evaluation (n = 2,595) predicted increased risks for both prevalent cardiovascular disease (CVD) and incident major adverse cardiac events (myocardial infarction, stroke or death), but only among subjects with concurrently high TMAO levels. Chronic dietary L-carnitine supplementation in mice altered cecal microbial composition, markedly enhanced synthesis of TMA and TMAO, and increased atherosclerosis, but this did not occur if intestinal microbiota was concurrently suppressed. In mice with an intact intestinal microbiota, dietary supplementation with TMAO or either carnitine or choline reduced in vivo reverse cholesterol transport. Intestinal microbiota may thus contribute to the well-established link between high levels of red meat consumption and CVD risk.


Assuntos
Aterosclerose/etiologia , Carnitina/metabolismo , Intestinos/microbiologia , Metagenoma , Animais , Aterosclerose/microbiologia , Aterosclerose/fisiopatologia , Carnitina/química , Colesterol/metabolismo , Colina/química , Desmosterol/metabolismo , Feminino , Humanos , Macrófagos/metabolismo , Espectrometria de Massas , Carne , Metilaminas/sangue , Metilaminas/metabolismo , Camundongos , Camundongos Knockout , RNA/metabolismo , Fatores de Tempo
19.
J Appl Microbiol ; 114(4): 982-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23294280

RESUMO

AIMS: To identify active phenolic constituents in muscadine grape skin (MGS) extracts and determine interactions among compounds while further exploring their anti-Helicobacter pylori potential in vitro. METHODS AND RESULTS: The inhibitory effects of quercetin and resveratrol, active polyphenols identified in MGS extracts, against H. pylori were investigated. Quercetin and resveratrol significantly (P < 0.05) reduced H. pylori counts regardless of pH with minimal bactericidal concentrations of 256 and 128 µg ml(-1), respectively. MGS extracts displayed the highest efficacy, suggesting additional unidentified compounds not determined in this study. Time-course viability experiments showed a dose-dependent anti-H. pylori response to quercetin and resveratrol. Interestingly, neither quercetin nor resveratrol affected H. pylori outer membrane (OM) integrity as determined by 1-N-phenylnaphthylamine (NPN) uptake assays. However, treatment with MGS extract did increase NPN uptake, indicating OM destabilization possibly by additional unknown components. Furthermore, quercetin was found to enter H. pylori as measured by HPLC supporting intracellular drug accumulation. CONCLUSIONS: Quercetin and resveratrol possess strong anti-H. pylori activity in vitro and are independent of pH. Our results also suggest that these compounds do not affect H. pylori OM integrity as previously hypothesized and that the primary antimicrobial activity of quercetin may be linked to interactions with intracellular components. SIGNIFICANCE AND IMPACT OF THE STUDY: The anti-H. pylori effects of quercetin and resveratrol suggest that these compounds may be useful in the dietary prevention and/or treatment of H. pylori infection.


Assuntos
Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Quercetina/farmacologia , Estilbenos/farmacologia , Vitis/química , 1-Naftilamina/análogos & derivados , Antibacterianos/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Helicobacter pylori/citologia , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Polifenóis/farmacologia , Resveratrol
20.
Opt Express ; 20(14): 16113-28, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22772302

RESUMO

We introduce a new computational approach for femtosecond pulse propagation in the transparency region of gases that permits full resolution in three space dimensions plus time while fully incorporating quantum coherent effects such as high-harmonic generation and strong-field ionization in a holistic fashion. This is achieved by utilizing a one-dimensional model atom with a delta-function potential which allows for a closed-form solution for the nonlinear optical response due to ground-state to continuum transitions. It side-steps evaluation of the wave function, and offers more than one hundred-fold reduction in computation time in comparison to direct solution of the atomic Schrödinger equation. To illustrate the capability of our new computational approach, we apply it to the example of near-threshold harmonic generation in Xenon, and we also present a qualitative comparison between our model and results from an in-house experiment on extreme ultraviolet generation in a femtosecond enhancement cavity.

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