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1.
Cell ; 177(3): 587-596.e9, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-31002795

RESUMO

Severe obesity is a rapidly growing global health threat. Although often attributed to unhealthy lifestyle choices or environmental factors, obesity is known to be heritable and highly polygenic; the majority of inherited susceptibility is related to the cumulative effect of many common DNA variants. Here we derive and validate a new polygenic predictor comprised of 2.1 million common variants to quantify this susceptibility and test this predictor in more than 300,000 individuals ranging from middle age to birth. Among middle-aged adults, we observe a 13-kg gradient in weight and a 25-fold gradient in risk of severe obesity across polygenic score deciles. In a longitudinal birth cohort, we note minimal differences in birthweight across score deciles, but a significant gradient emerged in early childhood and reached 12 kg by 18 years of age. This new approach to quantify inherited susceptibility to obesity affords new opportunities for clinical prevention and mechanistic assessment.


Assuntos
Peso Corporal , Herança Multifatorial/genética , Obesidade/patologia , Adolescente , Índice de Massa Corporal , Criança , Bases de Dados Factuais , Feminino , Estudo de Associação Genômica Ampla , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/genética , Fatores de Risco , Índice de Gravidade de Doença
2.
Nature ; 612(7940): 528-533, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477538

RESUMO

Sexual reproduction and meiotic sex are deeply rooted in the eukaryotic tree of life, but mechanisms determining sex or mating types are extremely varied and are only well characterized in a few model organisms1. In malaria parasites, sexual reproduction coincides with transmission to the vector host. Sex determination is non-genetic, with each haploid parasite capable of producing either a male or a female gametocyte in the human host2. The hierarchy of events and molecular mechanisms that trigger sex determination and maintenance of sexual identity are yet to be elucidated. Here we show that the male development 1 (md1) gene is both necessary and sufficient for male fate determination in the human malaria parasite Plasmodium falciparum. We show that Md1 has a dual function stemming from two separate domains: in sex determination through its N terminus and in male development from its conserved C-terminal LOTUS/OST-HTH domain. We further identify a bistable switch at the md1 locus, which is coupled with sex determination and ensures that the male-determining gene is not expressed in the female lineage. We describe one of only a few known non-genetic mechanisms of sex determination in a eukaryote and highlight Md1 as a potential target for interventions that block malaria transmission.


Assuntos
Regulação da Expressão Gênica , Malária Falciparum , Malária , Parasitos , Processos de Determinação Sexual , Transcrição Gênica , Animais , Humanos , Malária/parasitologia , Malária Falciparum/parasitologia , Parasitos/genética , Plasmodium falciparum/genética , Reprodução , Masculino , Feminino , Processos de Determinação Sexual/genética , Caracteres Sexuais
3.
Cell ; 149(2): 307-21, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22500798

RESUMO

Kinase inhibitors have limited success in cancer treatment because tumors circumvent their action. Using a quantitative proteomics approach, we assessed kinome activity in response to MEK inhibition in triple-negative breast cancer (TNBC) cells and genetically engineered mice (GEMMs). MEK inhibition caused acute ERK activity loss, resulting in rapid c-Myc degradation that induced expression and activation of several receptor tyrosine kinases (RTKs). RNAi knockdown of ERK or c-Myc mimicked RTK induction by MEK inhibitors, and prevention of proteasomal c-Myc degradation blocked kinome reprogramming. MEK inhibitor-induced RTK stimulation overcame MEK2 inhibition, but not MEK1 inhibition, reactivating ERK and producing drug resistance. The C3Tag GEMM for TNBC similarly induced RTKs in response to MEK inhibition. The inhibitor-induced RTK profile suggested a kinase inhibitor combination therapy that produced GEMM tumor apoptosis and regression where single agents were ineffective. This approach defines mechanisms of drug resistance, allowing rational design of combination therapies for cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , MAP Quinase Quinase 1/antagonistas & inibidores , Proteínas Quinases/genética , Proteoma/análise , Animais , Antineoplásicos/uso terapêutico , Benzenossulfonatos/uso terapêutico , Benzimidazóis/uso terapêutico , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Niacinamida/análogos & derivados , Compostos de Fenilureia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/genética , Sorafenibe
4.
N Engl J Med ; 389(6): 514-526, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37366315

RESUMO

BACKGROUND: Retatrutide (LY3437943) is an agonist of the glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and glucagon receptors. Its dose-response relationships with respect to side effects, safety, and efficacy for the treatment of obesity are not known. METHODS: We conducted a phase 2, double-blind, randomized, placebo-controlled trial involving adults who had a body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) of 30 or higher or who had a BMI of 27 to less than 30 plus at least one weight-related condition. Participants were randomly assigned in a 2:1:1:1:1:2:2 ratio to receive subcutaneous retatrutide (1 mg, 4 mg [initial dose, 2 mg], 4 mg [initial dose, 4 mg], 8 mg [initial dose, 2 mg], 8 mg [initial dose, 4 mg], or 12 mg [initial dose, 2 mg]) or placebo once weekly for 48 weeks. The primary end point was the percentage change in body weight from baseline to 24 weeks. Secondary end points included the percentage change in body weight from baseline to 48 weeks and a weight reduction of 5% or more, 10% or more, or 15% or more. Safety was also assessed. RESULTS: We enrolled 338 adults, 51.8% of whom were men. The least-squares mean percentage change in body weight at 24 weeks in the retatrutide groups was -7.2% in the 1-mg group, -12.9% in the combined 4-mg group, -17.3% in the combined 8-mg group, and -17.5% in the 12-mg group, as compared with -1.6% in the placebo group. At 48 weeks, the least-squares mean percentage change in the retatrutide groups was -8.7% in the 1-mg group, -17.1% in the combined 4-mg group, -22.8% in the combined 8-mg group, and -24.2% in the 12-mg group, as compared with -2.1% in the placebo group. At 48 weeks, a weight reduction of 5% or more, 10% or more, and 15% or more had occurred in 92%, 75%, and 60%, respectively, of the participants who received 4 mg of retatrutide; 100%, 91%, and 75% of those who received 8 mg; 100%, 93%, and 83% of those who received 12 mg; and 27%, 9%, and 2% of those who received placebo. The most common adverse events in the retatrutide groups were gastrointestinal; these events were dose-related, were mostly mild to moderate in severity, and were partially mitigated with a lower starting dose (2 mg vs. 4 mg). Dose-dependent increases in heart rate peaked at 24 weeks and declined thereafter. CONCLUSIONS: In adults with obesity, retatrutide treatment for 48 weeks resulted in substantial reductions in body weight. (Funded by Eli Lilly; ClinicalTrials.gov number, NCT04881760.).


Assuntos
Fármacos Antiobesidade , Polipeptídeo Inibidor Gástrico , Peptídeo 1 Semelhante ao Glucagon , Obesidade , Receptores de Glucagon , Adulto , Feminino , Humanos , Masculino , Índice de Massa Corporal , Método Duplo-Cego , Peptídeo 1 Semelhante ao Glucagon/agonistas , Obesidade/complicações , Obesidade/tratamento farmacológico , Resultado do Tratamento , Redução de Peso/efeitos dos fármacos , Polipeptídeo Inibidor Gástrico/agonistas , Receptores de Glucagon/agonistas , Injeções Subcutâneas , Fármacos Antiobesidade/administração & dosagem , Fármacos Antiobesidade/efeitos adversos , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/uso terapêutico
5.
Proc Natl Acad Sci U S A ; 120(1): e2215003120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36577076

RESUMO

We used a transgenic parasite in which Plasmodium falciparum parasites were genetically modified to express Plasmodium vivax apical membrane antigen 1 (PvAMA1) protein in place of PfAMA1 to study PvAMA1-mediated invasion. In P. falciparum, AMA1 interaction with rhoptry neck protein 2 (RON2) is known to be crucial for invasion, and PfRON2 peptides (PfRON2p) blocked the invasion of PfAMA1 wild-type parasites. However, PfRON2p has no effect on the invasion of transgenic parasites expressing PvAMA1 indicating that PfRON2 had no role in the invasion of PvAMA1 transgenic parasites. Interestingly, PvRON2p blocked the invasion of PvAMA1 transgenic parasites in a dose-dependent manner. We found that recombinant PvAMA1 domains 1 and 2 (rPvAMA1) bound to reticulocytes and normocytes indicating that PvAMA1 directly interacts with erythrocytes during the invasion, and invasion blocking of PvRON2p may result from it interfering with PvAMA1 binding to erythrocytes. It was previously shown that the peptide containing Loop1a of PvAMA1 (PvAMA1 Loop1a) is also bound to reticulocytes. We found that the Loop1a peptide blocked the binding of PvAMA1 to erythrocytes. PvAMA1 Loop1a has no polymorphisms in contrast to other PvAMA1 loops and may be an attractive vaccine target. We thus present the evidence that PvAMA1 binds to erythrocytes in addition to interacting with PvRON2 suggesting that the P. vivax merozoites may exploit complex pathways during the invasion process.


Assuntos
Malária Falciparum , Plasmodium vivax , Humanos , Proteínas de Protozoários/química , Antígenos de Protozoários , Eritrócitos/metabolismo , Plasmodium falciparum/metabolismo , Reticulócitos/metabolismo
6.
N Engl J Med ; 387(8): 692-703, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35833805

RESUMO

BACKGROUND: In eyes with diabetic macular edema, the relative efficacy of administering aflibercept monotherapy as compared with bevacizumab first with a switch to aflibercept if the eye condition does not improve sufficiently (a form of step therapy) is unclear. METHODS: At 54 clinical sites, we randomly assigned eyes in adults who had diabetic macular edema involving the macular center and a visual-acuity letter score of 24 to 69 (on a scale from 0 to 100, with higher scores indicating better visual acuity; Snellen equivalent, 20/320 to 20/50) to receive either 2.0 mg of intravitreous aflibercept or 1.25 mg of intravitreous bevacizumab. The drug was administered at randomization and thereafter according to the prespecified retreatment protocol. Beginning at 12 weeks, eyes in the bevacizumab-first group were switched to aflibercept therapy if protocol-specified criteria were met. The primary outcome was the mean change in visual acuity over the 2-year trial period. Retinal central subfield thickness and visual acuity at 2 years and safety were also assessed. RESULTS: A total of 312 eyes (in 270 adults) underwent randomization; 158 eyes were assigned to receive aflibercept monotherapy and 154 to receive bevacizumab first. Over the 2-year period, 70% of the eyes in the bevacizumab-first group were switched to aflibercept therapy. The mean improvement in visual acuity was 15.0 letters in the aflibercept-monotherapy group and 14.0 letters in the bevacizumab-first group (adjusted difference, 0.8 letters; 95% confidence interval, -0.9 to 2.5; P = 0.37). At 2 years, the mean changes in visual acuity and retinal central subfield thickness were similar in the two groups. Serious adverse events (in 52% of the patients in the aflibercept-monotherapy group and in 36% of those in the bevacizumab-first group) and hospitalizations for adverse events (in 48% and 32%, respectively) were more common in the aflibercept-monotherapy group. CONCLUSIONS: In this trial of treatment of moderate vision loss due to diabetic macular edema involving the center of the macula, we found no evidence of a significant difference in visual outcomes over a 2-year period between aflibercept monotherapy and treatment with bevacizumab first with a switch to aflibercept in the case of suboptimal response. (Funded by the National Institutes of Health; Protocol AC ClinicalTrials.gov number, NCT03321513.).


Assuntos
Inibidores da Angiogênese , Bevacizumab , Retinopatia Diabética , Edema Macular , Receptores de Fatores de Crescimento do Endotélio Vascular , Proteínas Recombinantes de Fusão , Adulto , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/uso terapêutico , Bevacizumab/administração & dosagem , Bevacizumab/efeitos adversos , Bevacizumab/uso terapêutico , Diabetes Mellitus/tratamento farmacológico , Retinopatia Diabética/complicações , Retinopatia Diabética/tratamento farmacológico , Humanos , Injeções Intravítreas , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Ranibizumab/efeitos adversos , Receptores de Fatores de Crescimento do Endotélio Vascular/administração & dosagem , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/efeitos adversos , Proteínas Recombinantes de Fusão/uso terapêutico , Fator A de Crescimento do Endotélio Vascular
7.
Physiol Genomics ; 56(7): 457-468, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38738316

RESUMO

Military training provides insight into metabolic responses under unique physiological demands that can be comprehensively characterized by global metabolomic profiling to identify potential strategies for improving performance. This study identified shared changes in metabolomic profiles across three distinct military training exercises, varying in magnitude and type of stress. Blood samples collected before and after three real or simulated military training exercises were analyzed using the same untargeted metabolomic profiling platform. Exercises included a 2-wk survival training course (ST, n = 36), a 4-day cross-country ski march arctic training (AT, n = 24), and a 28-day controlled diet- and exercise-induced energy deficit (CED, n = 26). Log2-fold changes of greater than ±1 in 191, 121, and 64 metabolites were identified in the ST, AT, and CED datasets, respectively. Most metabolite changes were within the lipid (57-63%) and amino acid metabolism (18-19%) pathways and changes in 87 were shared across studies. The largest and most consistent increases in shared metabolites were found in the acylcarnitine, fatty acid, ketone, and glutathione metabolism pathways, whereas the largest decreases were in the diacylglycerol and urea cycle metabolism pathways. Multiple shared metabolites were consistently correlated with biomarkers of inflammation, tissue damage, and anabolic hormones across studies. These three studies of real and simulated military training revealed overlapping alterations in metabolomic profiles despite differences in environment and the stressors involved. Consistent changes in metabolites related to lipid metabolism, ketogenesis, and oxidative stress suggest a potential common metabolomic signature associated with inflammation, tissue damage, and suppression of anabolic signaling that may characterize the unique physiological demands of military training.NEW & NOTEWORTHY The extent to which metabolomic responses are shared across diverse military training environments is unknown. Global metabolomic profiling across three distinct military training exercises identified shared metabolic responses with the largest changes observed for metabolites related to fatty acids, acylcarnitines, ketone metabolism, and oxidative stress. These changes also correlated with alterations in markers of tissue damage, inflammation, and anabolic signaling and comprise a potential common metabolomic signature underlying the unique physiological demands of military training.


Assuntos
Metaboloma , Metabolômica , Militares , Humanos , Metabolômica/métodos , Masculino , Adulto Jovem , Estresse Fisiológico/fisiologia , Adulto , Exercício Físico/fisiologia , Carnitina/análogos & derivados , Carnitina/sangue
8.
Clin Infect Dis ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801746

RESUMO

BACKGROUND: The optimal timing of vaccination with SARS-CoV-2 vaccines after cellular therapy is incompletely understood. The objectives of this study are to determine whether humoral and cellular responses after SARS-CoV-2 vaccination differ if initiated <4 months versus 4-12 months after cellular therapy. METHODS: We conducted a multicenter prospective observational study at 30 cancer centers in the United States. SARS-CoV-2 vaccination was administered as part of routine care. We obtained blood prior to and after vaccinations at up to five time points and tested for SARS-CoV-2 spike (anti-S) IgG in all participants and neutralizing antibodies for Wuhan D614G, Delta B.1.617.2, and Omicron B.1.1.529 strains, as well as SARS-CoV-2-specific T cell receptors (TCRs), in a subgroup. RESULTS: We enrolled 466 allogeneic hematopoietic cell transplant (HCT; n=231), autologous HCT (n=170), and chimeric antigen receptor T cell (CAR-T cell) therapy (n=65) recipients between April 2021 and June 2022. Humoral and cellular responses did not significantly differ among participants initiating vaccinations <4 months vs 4-12 months after cellular therapy. Anti-S IgG ≥2,500 U/mL was correlated with high neutralizing antibody titers and attained by the last time point in 70%, 69%, and 34% of allogeneic HCT, autologous HCT, and CAR-T cell recipients, respectively. SARS-CoV-2-specific T cell responses were attained in 57%, 83%, and 58%, respectively. Pre-cellular therapy SARS-CoV-2 infection or vaccination were key predictors of post-cellular therapy immunity. CONCLUSIONS: These data support mRNA SARS-CoV-2 vaccination prior to, and reinitiation three to four months after, cellular therapies with allogeneic HCT, autologous HCT, and CAR-T cell therapy.

9.
Am J Physiol Endocrinol Metab ; 326(3): E258-E267, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38170166

RESUMO

Sodium glucose cotransporter 2 inhibitors (SGLT2is) improved major adverse cardiovascular events (MACE), heart failure, and renal outcomes in large trials; however, a thorough understanding of the vascular physiological changes contributing to these responses is lacking. We hypothesized that SGLT2i therapy would diminish vascular insulin resistance and improve hemodynamic function, which could improve clinical outcomes. To test this, we treated 11 persons with type 2 diabetes for 12 wk with 10 mg/day empagliflozin and measured vascular stiffness, endothelial function, peripheral and central arterial pressures, skeletal and cardiac muscle perfusion, and vascular biomarkers before and at 120 min of a euglycemic hyperinsulinemic clamp at weeks 0 and 12. We found that before empagliflozin treatment, insulin infusion lowered peripheral and central aortic systolic pressure (P < 0.05) and muscle microvascular blood flow (P < 0.01), but showed no effect on other vascular measures. Following empagliflozin, insulin infusion improved endothelial function (P = 0.02), lowered peripheral and aortic systolic (each P < 0.01), diastolic (each P < 0.05), mean arterial (each P < 0.01), and pulse pressures (each P < 0.02), altered endothelial biomarker expression, and decreased radial artery forward and backward pressure amplitude (each P = 0.02). Empagliflozin also improved insulin-mediated skeletal and cardiac muscle microvascular perfusion (each P < 0.05). We conclude that empagliflozin enhances insulin's vascular actions, which could contribute to the improved cardiorenal outcomes seen with SGLT2i therapy.NEW & NOTEWORTHY The physiological underpinnings of the cardiovascular benefits of SGLT2 inhibitors remain uncertain. We tested whether empagliflozin mitigates vascular insulin resistance in patients with type 2 diabetes. Aortic and peripheral systolic, diastolic, mean and pulse pressures, endothelial function, vascular stiffness, and heart and muscle microvascular perfusion were measured before and during an insulin infusion at baseline and after 12 wk of empagliflozin. After empagliflozin, vascular responses to insulin improved dramatically.


Assuntos
Diabetes Mellitus Tipo 2 , Glucosídeos , Resistência à Insulina , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Compostos Benzidrílicos/farmacologia , Compostos Benzidrílicos/uso terapêutico , Miocárdio/metabolismo , Insulina/metabolismo , Biomarcadores , Perfusão
10.
Immunol Cell Biol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629880

RESUMO

The significance of metabolites in orchestrating immune cells is now recognized to be on par with other key immune modulators, such as cytokines or chemokines. Seminal discoveries have now been built upon with discoveries that have acted to take the discipline to new heights, particularly in T-cell immunity. This accelerated progress has uncovered a plethora of opportunities for pharmacological intervention, with the aim of harnessing immunometabolism for refined immune modulation across several pathologies. This Research Highlight focuses on the latest breakthroughs during 2023 from the preceding year that provide mechanistic insight, as well as viable translational opportunities, in the field of T-cell immunometabolism.

11.
Immunol Cell Biol ; 102(5): 331-335, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38111272

RESUMO

As part of the Monash Sensory Science Exhibition, our team guided participants through a multisensory journey unraveling coeliac disease development and pathology. Through tactile and sensory exhibits, we showed how benign dietary gluten can be transformed into a harmful entity for the 1 in 70 Australians with this illness. In contrast to the common misconception of coeliac disease as a food allergy, our exhibits revealed its closer association with autoimmune diseases such as type 1 diabetes, involving genetic susceptibility linked to specific human leukocyte antigens, crucial antigen-specific T- and B-cell responses and autoantibody production. Tactile models underscored the severe consequences of the proinflammatory immune response to gluten on patient health and quality of life. This educational event affirmed to us the value and importance of fostering inclusivity in science education.


Assuntos
Doença Celíaca , Glutens , Doença Celíaca/imunologia , Doença Celíaca/etiologia , Humanos , Glutens/imunologia , Tato , Austrália , Diabetes Mellitus Tipo 1/imunologia , Autoanticorpos/imunologia
12.
Am J Physiol Regul Integr Comp Physiol ; 327(1): R25-R34, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38682243

RESUMO

Insulin insensitivity decreases exogenous glucose oxidation and metabolic clearance rate (MCR) during aerobic exercise in unacclimatized lowlanders at high altitude (HA). Whether use of an oral insulin sensitizer before acute HA exposure enhances exogenous glucose oxidation is unclear. This study investigated the impact of pioglitazone (PIO) on exogenous glucose oxidation and glucose turnover compared with placebo (PLA) during aerobic exercise at HA. With the use of a randomized crossover design, native lowlanders (n = 7 males, means ± SD, age: 23 ± 6 yr, body mass: 84 ± 11 kg) consumed 145 g (1.8 g/min) of glucose while performing 80 min of steady-state (1.43 ± 0.16 V̇o2 L/min) treadmill exercise at HA (460 mmHg; [Formula: see text] 96.6 mmHg) following short-term (5 days) use of PIO (15 mg oral dose per day) or PLA (microcrystalline cellulose pill). Substrate oxidation and glucose turnover were determined using indirect calorimetry and stable isotopes ([13C]glucose and 6,6-[2H2]glucose). Exogenous glucose oxidation was not different between PIO (0.31 ± 0.03 g/min) and PLA (0.32 ± 0.09 g/min). Total carbohydrate oxidation (PIO: 1.65 ± 0.22 g/min, PLA: 1.68 ± 0.32 g/min) or fat oxidation (PIO: 0.10 ± 0.0.08 g/min, PLA: 0.09 ± 0.07 g/min) was not different between treatments. There was no treatment effect on glucose rate of appearance (PIO: 2.46 ± 0.27, PLA: 2.43 ± 0.27 mg/kg/min), disappearance (PIO: 2.19 ± 0.17, PLA: 2.20 ± 0.22 mg/kg/min), or MCR (PIO: 1.63 ± 0.37, PLA: 1.73 ± 0.40 mL/kg/min). Results from this study indicate that PIO is not an effective intervention to enhance exogenous glucose oxidation or MCR during acute HA exposure. Lack of effect with PIO suggests that the etiology of glucose metabolism dysregulation during acute HA exposure may not result from insulin resistance in peripheral tissues.NEW & NOTEWORTHY Short-term (5 days) use of the oral insulin sensitizer pioglitazone does not alter circulating glucose or insulin responses to enhance exogenous glucose oxidation during steady-state aerobic exercise in young healthy men under simulated acute (8 h) high-altitude (460 mmHg) conditions. These results indicate that dysregulations in glucose metabolism in native lowlanders sojourning at high altitude may not be due to insulin resistance at peripheral tissue.


Assuntos
Altitude , Estudos Cross-Over , Exercício Físico , Glucose , Hipoglicemiantes , Oxirredução , Pioglitazona , Humanos , Pioglitazona/administração & dosagem , Pioglitazona/farmacologia , Masculino , Adulto Jovem , Exercício Físico/fisiologia , Adulto , Glucose/metabolismo , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Hipoglicemiantes/farmacocinética , Taxa de Depuração Metabólica , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Insulina/sangue , Insulina/metabolismo
13.
Hepatology ; 77(2): 530-545, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36069569

RESUMO

BACKGROUND AND AIMS: Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis. APPROACH AND RESULTS: A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS. CONCLUSIONS: Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.


Assuntos
Síndrome de Alagille , Colestase , Técnicas de Imagem por Elasticidade , Hepatopatias , Humanos , Criança , Fígado/patologia , Metaloproteinase 7 da Matriz , Endoglina , Interleucina-8 , Colestase/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Hepatopatias/patologia , Biomarcadores , Síndrome de Alagille/patologia
14.
Ann Surg Oncol ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700800

RESUMO

BACKGROUND: Centralization of hepatopancreatobiliary procedures to more experienced centers has been recommended but remains controversial. Hospital volume and risk-stratified mortality rates (RSMR) are metrics for interhospital comparison. We compared facility operative volume with facility RSMR as a proxy for hospital quality. PATIENTS AND METHODS: Patients who underwent surgery for liver (LC), biliary tract (BTC), and pancreatic (PDAC) cancer were identified in the National Cancer Database (2004-2018). Hierarchical logistic regression was used to create facility-specific models for RSMR. Volume (high versus low) was determined by quintile. Performance (high versus low) was determined by RSMR tercile. Primary outcomes included median facility RSMR and RSMR distributions. Volume- and RSMR-based redistribution was simulated and compared for reductions in 90-day mortality. RESULTS: A total of 106,217 patients treated at 1282 facilities were included; 17,695 had LC, 23,075 had BTC, and 65,447 had PDAC. High-volume centers (HVC) had lower RSMR compared with medium-volume centers and low-volume centers for LC, BTC, and PDAC (all p < 0.001). High-performance centers (HPC) had lower RSMR compared with medium-performance centers and low-performance centers for LC, BTC, and PDAC (all p < 0.001). Volume-based redistribution required 16.0 patients for LC, 11.2 for BTC, and 14.9 for PDAC reassigned to 15, 22, and 20 centers, respectively, per life saved within each US census region. RSMR-based redistribution required 4.7 patients for LC, 4.2 for BTC, and 4.9 for PDAC reassigned to 316, 403, and 418 centers, respectively, per life saved within each US census region. CONCLUSIONS: HVC and HPC have the lowest overall and risk-standardized 90-day mortality after oncologic hepatopancreatobiliary procedures, but RSMR may outperform volume as a measure of hospital quality.

15.
Ann Surg Oncol ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896228

RESUMO

BACKGROUND: The study determined the proportion of patients with pancreatic adenocarcinoma (PDAC) who had margin-positive disease and no other adverse pathologic findings (APF) using institutional and administrative datasets. METHODS: Patients with clinical stage I or II PDAC in the National Cancer Database (NCDB 2010-2020) and those who underwent pancreatectomy at the authors' institution (2010-2021) were identified. Isolated margin positivity (IMP) was defined as a positive surgical margin with no APF (negative nodes, no lymphovascular/perineural invasion). RESULTS: The study included 225 patients from the authors' institution and 23,598 patients from the NCDB. The margin-positive rates were 21.8% and 20.3%, and the IMP rates were 0.4% and 0.5%, respectively. In the institutional cohort, 68.4% of the patients had recurrence, and most of the patients (65.6%) had distant recurrences. The median recurrence-free survival (RFS) was 63.3 months for no APF, not reached for IMP, 14.8 months for negative margins & 1 APF, 20.3 months for positive margins & 2 APFs, and 12.9 months with all APF positive. The patients in the NCDB with IMP had a lower median OS than the patients with no APF (20.5 vs 390 months), but a higher median OS than those with margin positivity plus 1 APF (20.5 vs 18.0 months) or all those with APF positivity (20.5 vs 15.4 months). Based on institutional rates of IMP, any margin positivity, neck margin positivity (NMP), and no APF, the fraction of patients who might benefit from neck margin revision was 1 in 100,000, and those likely to benefit from any margin revision was 1 in 18,500. In the NCDB, those estimated to derive potential benefit from margin revision was 1 in 25,000. CONCLUSIONS: Isolated margin positivity in resected PDAC is rare, and most patients experience distant recurrence. Revision of IMP appears unlikely to confer benefit to most patients.

16.
Ann Surg Oncol ; 31(7): 4413-4426, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38502296

RESUMO

BACKGROUND: Treatment of unresectable colorectal liver metastases (UCRLM) includes locoregional and systemic therapy. A comprehensive analysis capturing long-term outcomes of these treatment options has not been performed. OBJECTIVE: A systematic review and meta-analysis was performed to calculate pooled outcomes of hepatic artery infusion with systemic chemotherapy (HAI-S), transarterial chemoembolization with systemic chemotherapy (TACE-S), transarterial radioembolization with systemic chemotherapy (TARE-S), doublet (FOLFOX, FOLFIRI), and triplet chemotherapy (FOLFOXIRI). METHODS: Outcomes included overall survival (OS), progression-free survival (PFS), rate of conversion to resection (CTR), and response rate (RR). RESULTS: A total of 32, 7, 9, and 14 publications were included in the HAI-S, TACE-S, and TARE-S chemotherapy arms. The 6/12/24/36-month OS estimates for HAI-S, TACE-S, TARE-S, FOLFOX, FOLFIRI, and FOLFOXIRI were 97%/80%/54%/35%, 100%/83%/40%/14%, 82%/61%/34%/21%, 96%/83%/53%/36%, and 96%/93%/72%/55%. Similarly, the 6/12/24/36-month PFS estimates were 74%/44%/19%/14%, 66%/20%/9%/3%, 57%/23%/10%/3%, 69%/30%/12%/7%, and 88%/55%/18%/11%. The corresponding CTR and RR rates were 31, 20%, unmeasurable (TARE-S), 35, 53; and 49, 45, 45, 50, 80%, respectively. The majority of chemotherapy studies included first-line therapy and liver-only metastases, whereas most HAI-S studies were pretreated. On subgroup analysis in first-line setting with liver-only metastases, the HAI-S arm had comparable outcomes to FOLFOXIRI and outperformed doublet chemotherapy regimens. Although triplet chemotherapy appeared to outperform other arms, high toxicity and inclusion of potentially resectable patients must be considered while interpreting results. CONCLUSIONS: HAI-S and multiagent chemotherapy are effective therapies for UCRLM. To make definitive conclusions, a randomized trial with comparable patient characteristics and line of therapy will be required. The upcoming EA2222 PUMP trial may help to address this question.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Quimioembolização Terapêutica , Neoplasias Colorretais , Artéria Hepática , Infusões Intra-Arteriais , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Neoplasias Colorretais/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioembolização Terapêutica/métodos , Taxa de Sobrevida , Prognóstico , Fluoruracila/administração & dosagem , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico
17.
Ophthalmology ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38336282

RESUMO

PURPOSE: To identify factors for meeting prespecified criteria for switching from bevacizumab to aflibercept in eyes with center-involved diabetic macular edema (CI-DME) and moderate vision loss initially treated with bevacizumab in DRCR Retina Network protocol AC. DESIGN: Post hoc analysis of data from a randomized clinical trial. PARTICIPANTS: Two hundred seventy participants with one or both eyes harboring CI-DME with visual acuity (VA) letter score of 69 to 24 (Snellen equivalent, 20/50-20/320). METHODS: Eligible eyes were assigned to receive intravitreal aflibercept monotherapy (n = 158) or bevacizumab followed by aflibercept if prespecified criteria for switching were met between 12 weeks and 2 years (n = 154). MAIN OUTCOME MEASURES: Meeting switching criteria: (1) at any time, (2) at 12 weeks, and (3) after 12 weeks. Associations between meeting the criteria for switching and factors measured at baseline and 12 weeks were evaluated in univariable analyses. Stepwise procedures were used to select variables for multivariable models. RESULTS: In the group receiving bevacizumab first, older participants showed a higher risk of meeting the switching criteria at any time, with a hazard ratio (HR) for a 10-year increase in age of 1.32 (95% confidence interval [CI], 1.11-1.58). Male participants or eyes with worse baseline VA were more likely to switch at 12 weeks (for male vs. female: odds ratio [OR], 4.84 [95% CI, 1.32-17.81]; 5-letter lower baseline VA: OR, 1.30 [95% CI, 1.03-1.63]). Worse 12-week central subfield thickness (CST; 10-µm greater: HR, 1.06 [95% CI, 1.04-1.07]) was associated with increased risk of switching after 12 weeks. The mean ± standard deviation improvement in visual acuity after completing the switch to aflibercept was 3.7 ± 4.9 letters compared with the day of switching. CONCLUSIONS: The identified factors can be used to refine expectations regarding the likelihood that an eye will meet protocol criteria to switch to aflibercept when treatment is initiated with bevacizumab. Older patients are more likely to be switched. At 12 weeks, thicker CST was predictive of eyes most likely to be switched in the future. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

18.
Blood ; 140(13): 1482-1495, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-35820055

RESUMO

Molecular programs initiating cell fate divergence (CFD) are difficult to identify. Current approaches usually compare cells long after CFD initiation, therefore missing molecular changes at its start. Ideally, single cells that differ in their CFD molecular program but are otherwise identical are compared early in CFD. This is possible in diverging sister cells, which were identical until their mother's division and thus differ mainly in CFD properties. In asymmetrically dividing cells, divergent daughter fates are prospectively committed during division, and diverging sisters can thus be identified at the start of CFD. Using asymmetrically dividing blood stem cells, we developed a pipeline (ie, trackSeq) for imaging, tracking, isolating, and transcriptome sequencing of single cells. Their identities, kinship, and histories are maintained throughout, massively improving molecular noise filtering and candidate identification. In addition to many identified blood stem CFD regulators, we offer here this pipeline for use in CFDs other than asymmetric division.


Assuntos
Rastreamento de Células , Células-Tronco , Diferenciação Celular , Divisão Celular
19.
Phys Rev Lett ; 132(13): 131001, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613296

RESUMO

We searched for antideuterons (d[over ¯]'s) in the 4.7×10^{9} cosmic-ray events observed during the BESS-Polar II flight at solar minimum in 2007-2008 but found no candidates. The resulting 95% C.L. upper limit on the d[over ¯] flux is 6.7×10^{-5} (m^{2} s sr GeV/n)^{-1} in an energy range from 0.163 to 1.100 GeV/n. The result has improved by more than a factor of 14 from the upper limit of BESS97, which had a potential comparable to that of BESS-Polar II in the search for cosmic-origin d[over ¯]'s and was conducted during the former solar minimum. The upper limit of d[over ¯] flux from BESS-Polar II is the first result achieving the sensitivity to constrain the latest theoretical predictions.

20.
J Nutr ; 154(6): 1758-1765, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677478

RESUMO

BACKGROUND: Considerable controversy exists surrounding the consumption of red meat and its impacts on cardiometabolic health and if it may further impact risk factors at the molecular level. OBJECTIVE: The purpose of this study was to examine the acute effects of dietary patterns, varying in red meat quantity, on the expression of circulating microRNAs (miRNAs), which are emerging biomarkers of metabolic dysfunction and chronic disease severity. METHODS: Secondary analyses were performed on plasma samples collected within a randomized, crossover design study in 16 women with overweight (mean ± standard deviation, age = 33 ± 9.89 y; body mass index = 27.9 ± 1.66 kg/m2). Participants were provided with eucaloric, isonitrogenous diets (15% of daily intake as protein) containing either 2 servings of fresh, lean beef/day (BEEF) or 0 servings of fresh, lean beef/day (PLANT) for 7 d/pattern. Fasting blood samples were collected at the end of each dietary pattern for the assessment of 12 circulating metabolic miRNA expression levels (determined a priori by quantitative reverse transcriptase-polymerase chain reaction), plasma glucose, insulin, interleukin-6, tumor necrosis factor-α, C-reactive protein (CRP), adiponectin, glucagon-like peptide-1, and branched-chain amino acids. RESULTS: Of the 12 miRNAs, miR-15b-5p expression was higher following BEEF versus PLANT (P = 0.024). Increased miR-15b-5p expression correlated with decreased fasting CRP (r = -0.494; P = 0.086) and insulin concentrations (r = -0.670; P = 0.017). miR-15b-5p was inversely correlated with insulin resistance (r = -0.642; P = 0.024) and ß cell function (r = -0.646; P = 0.023) and positively correlated with markers of insulin sensitivity (r = 0.520; P = 0.083). However, the correlations were only observed following BEEF, not PLANT. CONCLUSIONS: These data indicate that the short-term intake of fresh, lean beef as part of a healthy dietary pattern impacts potential biomarkers of cardiometabolic health that are associated with cardiometabolic risk factors in women with overweight. This study was registered at clinicaltrials.gov as NCT02614729.


Assuntos
Biomarcadores , Estudos Cross-Over , MicroRNAs , Carne Vermelha , MicroRNAs/sangue , Feminino , Humanos , Adulto , Biomarcadores/sangue , Bovinos , Animais , Doenças Cardiovasculares , Fatores de Risco Cardiometabólico , Dieta Saudável , Dieta , Fatores de Risco , Padrões Dietéticos
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