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1.
Cell ; 159(2): 318-32, 2014 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-25303528

RESUMO

Increased adipose tissue lipogenesis is associated with enhanced insulin sensitivity. Mice overexpressing the Glut4 glucose transporter in adipocytes have elevated lipogenesis and increased glucose tolerance despite being obese with elevated circulating fatty acids. Lipidomic analysis of adipose tissue revealed the existence of branched fatty acid esters of hydroxy fatty acids (FAHFAs) that were elevated 16- to 18-fold in these mice. FAHFA isomers differ by the branched ester position on the hydroxy fatty acid (e.g., palmitic-acid-9-hydroxy-stearic-acid, 9-PAHSA). PAHSAs are synthesized in vivo and regulated by fasting and high-fat feeding. PAHSA levels correlate highly with insulin sensitivity and are reduced in adipose tissue and serum of insulin-resistant humans. PAHSA administration in mice lowers ambient glycemia and improves glucose tolerance while stimulating GLP-1 and insulin secretion. PAHSAs also reduce adipose tissue inflammation. In adipocytes, PAHSAs signal through GPR120 to enhance insulin-stimulated glucose uptake. Thus, FAHFAs are endogenous lipids with the potential to treat type 2 diabetes.


Assuntos
Tecido Adiposo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ésteres/metabolismo , Ácidos Graxos/metabolismo , Adulto , Animais , Diabetes Mellitus Tipo 2/dietoterapia , Dieta , Ésteres/administração & dosagem , Ésteres/análise , Ácidos Graxos/administração & dosagem , Ácidos Graxos/análise , Feminino , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Humanos , Inflamação/dietoterapia , Insulina/metabolismo , Resistência à Insulina , Lipogênese , Masculino , Espectrometria de Massas , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Receptores Acoplados a Proteínas G/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(28): e2318691121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38968121

RESUMO

Dietary lipids play an essential role in regulating the function of the gut microbiota and gastrointestinal tract, and these luminal interactions contribute to mediating host metabolism. Palmitic Acid Hydroxy Stearic Acids (PAHSAs) are a family of lipids with antidiabetic and anti-inflammatory properties, but whether the gut microbiota contributes to their beneficial effects on host metabolism is unknown. Here, we report that treating chow-fed female and male germ-free (GF) mice with PAHSAs improves glucose tolerance, but these effects are lost upon high fat diet (HFD) feeding. However, transfer of feces from PAHSA-treated, but not vehicle-treated, chow-fed conventional mice increases insulin sensitivity in HFD-fed GF mice. Thus, the gut microbiota is necessary for, and can transmit, the insulin-sensitizing effects of PAHSAs in HFD-fed GF male mice. Analyses of the cecal metagenome and lipidome of PAHSA-treated mice identified multiple lipid species that associate with the gut commensal Bacteroides thetaiotaomicron (Bt) and with insulin sensitivity resulting from PAHSA treatment. Supplementing live, and to some degree, heat-killed Bt to HFD-fed female mice prevented weight gain, reduced adiposity, improved glucose tolerance, fortified the colonic mucus barrier and reduced systemic inflammation compared to HFD-fed controls. These effects were not observed in HFD-fed male mice. Furthermore, ovariectomy partially reversed the beneficial Bt effects on host metabolism, indicating a role for sex hormones in mediating the Bt probiotic effects. Altogether, these studies highlight the fact that PAHSAs can modulate the gut microbiota and that the microbiota is necessary for the beneficial metabolic effects of PAHSAs in HFD-fed mice.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal , Resistência à Insulina , Obesidade , Animais , Masculino , Feminino , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Obesidade/metabolismo , Obesidade/microbiologia , Obesidade/etiologia , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Ácidos Esteáricos/metabolismo , Ácido Palmítico/metabolismo , Fezes/microbiologia , Camundongos Obesos
4.
Nucleic Acids Res ; 52(10): 5756-5773, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38587189

RESUMO

Dynamic interaction between BRCA2 and telomeric G-quadruplexes (G4) is crucial for maintaining telomere replication homeostasis. Cells lacking BRCA2 display telomeric damage with a subset of these cells bypassing senescence to initiate break-induced replication (BIR) for telomere synthesis. Here we show that the abnormal stabilization of telomeric G4 following BRCA2 depletion leads to telomeric repeat-containing RNA (TERRA)-R-loop accumulation, triggering liquid-liquid phase separation (LLPS) and the assembly of Alternative Lengthening of Telomeres (ALT)-associated promyelocytic leukemia (PML) bodies (APBs). Disruption of R-loops abolishes LLPS and impairs telomere synthesis. Artificial engineering of telomeric LLPS restores telomere synthesis, underscoring the critical role of LLPS in ALT. TERRA-R-loops also recruit Polycomb Repressive Complex 2 (PRC2), leading to tri-methylation of Lys27 on histone H3 (H3K27me3) at telomeres. Half of paraffin-embedded tissue sections from human breast cancers exhibit APBs and telomere length heterogeneity, suggesting that BRCA2 mutations can predispose individuals to ALT-type tumorigenesis. Overall, BRCA2 abrogation disrupts the dynamicity of telomeric G4, producing TERRA-R-loops, finally leading to the assembly of telomeric liquid condensates crucial for ALT. We propose that modulating the dynamicity of telomeric G4 and targeting TERRA-R-loops in telomeric LLPS maintenance may represent effective therapeutic strategies for treating ALT-like cancers with APBs, including those with BRCA2 disruptions.


Assuntos
Proteína BRCA2 , Replicação do DNA , Quadruplex G , Homeostase do Telômero , Telômero , Humanos , Telômero/metabolismo , Telômero/genética , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Homeostase do Telômero/genética , Replicação do DNA/genética , Histonas/metabolismo , Histonas/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Estruturas R-Loop , Complexo Repressor Polycomb 2/metabolismo , Complexo Repressor Polycomb 2/genética , Linhagem Celular Tumoral , Feminino , Separação de Fases
5.
Proc Natl Acad Sci U S A ; 120(42): e2313133120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37812697

RESUMO

Water is a ubiquitous and vital component of living systems. Hydration, which is the interaction between water and intracellular biomolecules, plays an important role in cellular processes. However, it is technically challenging to study water structure within cells directly. Here, we demonstrate the utility and power of the water bend-libration combination band as a unique Raman spectral imaging probe of cellular hydration. Hydration maps reveal distinct water environments within subcellular compartments (e.g., nucleolus and lipid droplet) due to the spectral sensitivity of this coupled vibrational band. Spectroscopic studies using the water bend-libration are broadly applicable, offering the potential to capture the chemical complexity of hydration in numerous systems.


Assuntos
Análise Espectral Raman , Água , Água/química , Análise Espectral
6.
Blood ; 142(2): 185-196, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37146247

RESUMO

Pregnancy rates in ß-thalassemia are increasing but the risk of complications is higher; thus, better understanding of maternal and fetal iron homeostasis in this disorder is needed. HbbTh3/+ (Th3/+) mice model human ß-thalassemia. Both the murine and human diseases are characterized by low hepcidin, high iron absorption, and tissue iron overload, with concurrent anemia. We hypothesized that disordered iron metabolism in pregnant Th3/+ mice would negatively affect their unborn offspring. The experimental design included these groups: wild-type (WT) dams carrying WT fetuses (WT1); WT dams carrying WT and Th3/+ fetuses (WT2); Th3/+ dams carrying WT and Th3/+ fetuses (Th3/+); and age-matched, nonpregnant adult females. Serum hepcidin was low, and mobilization of splenic and hepatic storage iron was enhanced in all 3 groups of experimental dams. Intestinal 59Fe absorption was lower in Th3/+ dams (as compared with WT1/2 dams) but splenic 59Fe uptake was higher. Th3/+ dams had hyperferremia, which led to fetal and placenta iron loading, fetal growth restriction, and placentomegaly. Notably, Th3/+ dams loaded Th3/+ and WT fetuses, with the latter situation more closely mirroring human circumstances when mothers with thalassemia have relatively unaffected (thalassemia trait) offspring. Iron-related oxidative stress likely contributed to fetal growth impairment; enhanced placental erythropoiesis is a probable cause of placental enlargement. Moreover, high fetal liver iron transactivated Hamp; fetal hepcidin downregulated placental ferroportin expression, limiting placental iron flux and thus mitigating fetal iron loading. Whether gestational iron loading occurs in human thalassemic pregnancy, when blood transfusion can further elevate serum iron, is worth consideration.


Assuntos
Hepcidinas , Talassemia beta , Camundongos , Feminino , Humanos , Gravidez , Animais , Talassemia beta/metabolismo , Placenta/metabolismo , Ferro/metabolismo , Feto/metabolismo , Homeostase
7.
Proc Natl Acad Sci U S A ; 119(47): e2206923119, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36375063

RESUMO

Senescence in pancreatic beta cells plays a major role in beta cell dysfunction, which leads to impaired glucose homeostasis and diabetes. Therefore, prevention of beta cell senescence could reduce the risk of diabetes. Treatment of nonobese diabetic (NOD) mice, a model of type 1 autoimmune diabetes (T1D), with palmitic acid hydroxy stearic acids (PAHSAs), a novel class of endogenous lipids with antidiabetic and antiinflammatory effects, delays the onset and reduces the incidence of T1D from 82% with vehicle treatment to 35% with PAHSAs. Here, we show that a major mechanism by which PAHSAs protect islets of the NOD mice is by directly preventing and reversing the initial steps of metabolic stress-induced senescence. In vitro PAHSAs increased Mdm2 expression, which decreases the stability of p53, a key inducer of senescence-related genes. In addition, PAHSAs enhanced expression of protective genes, such as those regulating DNA repair and glutathione metabolism and promoting autophagy. We demonstrate the translational relevance by showing that PAHSAs prevent and reverse early stages of senescence in metabolically stressed human islets by the same Mdm2 mechanism. Thus, a major mechanism for the dramatic effect of PAHSAs in reducing the incidence of type 1 diabetes in NOD mice is decreasing cellular senescence; PAHSAs may have a similar benefit in humans.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Humanos , Camundongos , Animais , Ácido Palmítico/farmacologia , Ácidos Esteáricos , Camundongos Endogâmicos NOD , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/prevenção & controle , Proteína Supressora de Tumor p53/genética , Senescência Celular/genética , Estresse Fisiológico , Proteínas Proto-Oncogênicas c-mdm2/genética
8.
PLoS Med ; 21(3): e1004367, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38498589

RESUMO

BACKGROUND: While national adoption of universal HIV treatment guidelines has led to improved, timely uptake of antiretroviral therapy (ART), longer-term care outcomes are understudied. There is little data from real-world service delivery settings on patient attrition, viral load (VL) monitoring, and viral suppression (VS) at 24 and 36 months after HIV treatment initiation. METHODS AND FINDINGS: For this retrospective cohort analysis, we used observational data from 25 countries in the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium's Asia-Pacific, Central Africa, East Africa, Central/South America, and North America regions for patients who were ART naïve and aged ≥15 years at care enrollment between 24 months before and 12 months after national adoption of universal treatment guidelines, occurring 2012 to 2018. We estimated crude cumulative incidence of loss-to-clinic (CI-LTC) at 12, 24, and 36 months after enrollment among patients enrolling in care before and after guideline adoption using competing risks regression. Guideline change-associated hazard ratios of LTC at each time point after enrollment were estimated via cause-specific Cox proportional hazards regression models. Modified Poisson regression was used to estimate relative risks of retention, VL monitoring, and VS at 12, 24, and 36 months after ART initiation. There were 66,963 patients enrolling in HIV care at 109 clinics with ≥12 months of follow-up time after enrollment (46,484 [69.4%] enrolling before guideline adoption and 20,479 [30.6%] enrolling afterwards). More than half (54.9%) were females, and median age was 34 years (interquartile range [IQR]: 27 to 43). Mean follow-up time was 51 months (standard deviation: 17 months; range: 12, 110 months). Among patients enrolling before guideline adoption, crude CI-LTC was 23.8% (95% confidence interval [95% CI] 23.4, 24.2) at 12 months, 31.0% (95% CI [30.6, 31.5]) at 24 months, and 37.2% (95% [CI 36.8, 37.7]) at 36 months after enrollment. Adjusting for sex, age group, enrollment CD4, clinic location and type, and country income level, enrolling in care and initiating ART after guideline adoption was associated with increased hazard of LTC at 12 months (adjusted hazard ratio [aHR] 1.25 [95% CI 1.08, 1.44]; p = 0.003); 24 months (aHR 1.38 [95% CI 1.19, 1.59]; p < .001); and 36 months (aHR 1.34 [95% CI 1.18, 1.53], p < .001) compared with enrollment before guideline adoption, with no before-after differences among patients with no record of ART initiation by end of follow-up. Among patients retained after ART initiation, VL monitoring was low, with marginal improvements associated with guideline adoption only at 12 months after ART initiation. Among those with VL monitoring, VS was high at each time point among patients enrolling before guideline adoption (86.0% to 88.8%) and afterwards (86.2% to 90.3%), with no substantive difference associated with guideline adoption. Study limitations include lags in and potential underascertainment of care outcomes in real-world service delivery data and potential lack of generalizability beyond IeDEA sites and regions included in this analysis. CONCLUSIONS: In this study, adoption of universal HIV treatment guidelines was associated with lower retention after ART initiation out to 36 months of follow-up, with little change in VL monitoring or VS among retained patients. Monitoring long-term HIV care outcomes remains critical to identify and address causes of attrition and gaps in HIV care quality.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Feminino , Humanos , Masculino , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Estudos de Coortes , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Observação , Adolescente
9.
Biochem Soc Trans ; 52(3): 1121-1130, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38666616

RESUMO

Neurodegenerative diseases, such as Alzheimer's and Parkinson's, share a common pathological feature of amyloid structure accumulation. However, the structure-function relationship between these well-ordered, ß-sheet-rich, filamentous protein deposits and disease etiology remains to be defined. Recently, an emerging hypothesis has linked phase separation, a process involved in the formation of protein condensates, to amyloid formation, suggesting that liquid protein droplets serve as loci for amyloid initiation. To elucidate how these processes contribute to disease progression, tools that can directly report on protein secondary structural changes are needed. Here, we review recent studies that have demonstrated Raman spectroscopy as a powerful vibrational technique for interrogating amyloid structures; one that offers sensitivity from the global secondary structural level to specific residues. This probe-free technique is further enhanced via coupling to a microscope, which affords structural data with spatial resolution, known as Raman spectral imaging (RSI). In vitro and in cellulo applications of RSI are discussed, highlighting studies of protein droplet aging, cellular internalization of fibrils, and Raman imaging of intracellular water. Collectively, utilization of the myriad Raman spectroscopic methods will contribute to a deeper understanding of protein conformational dynamics in the complex cellular milieu and offer potential clinical diagnostic capabilities for protein misfolding and aggregation processes in disease states.


Assuntos
Amiloide , Análise Espectral Raman , Análise Espectral Raman/métodos , Humanos , Amiloide/química , Amiloide/metabolismo , Doenças Neurodegenerativas/metabolismo , Doença de Alzheimer/metabolismo , Estrutura Secundária de Proteína , Separação de Fases
10.
Genet Med ; 26(5): 101075, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38251460

RESUMO

PURPOSE: This study aims to assess the diagnostic utility and provide reporting recommendations for clinical DNA methylation episignature testing based on the cohort of patients tested through the EpiSign Clinical Testing Network. METHODS: The EpiSign assay utilized unsupervised clustering techniques and a support vector machine-based classification algorithm to compare each patient's genome-wide DNA methylation profile with the EpiSign Knowledge Database, yielding the result that was reported. An international working group, representing distinct EpiSign Clinical Testing Network health jurisdictions, collaborated to establish recommendations for interpretation and reporting of episignature testing. RESULTS: Among 2399 cases analyzed, 1667 cases underwent a comprehensive screen of validated episignatures, imprinting, and promoter regions, resulting in 18.7% (312/1667) positive reports. The remaining 732 referrals underwent targeted episignature analysis for assessment of sequence or copy-number variants (CNVs) of uncertain significance or for assessment of clinical diagnoses without confirmed molecular findings, and 32.4% (237/732) were positive. Cases with detailed clinical information were highlighted to describe various utility scenarios for episignature testing. CONCLUSION: Clinical DNA methylation testing including episignatures, imprinting, and promoter analysis provided by an integrated network of clinical laboratories enables test standardization and demonstrates significant diagnostic yield and clinical utility beyond DNA sequence analysis in rare diseases.


Assuntos
Metilação de DNA , Testes Genéticos , Doenças Raras , Humanos , Metilação de DNA/genética , Doenças Raras/genética , Doenças Raras/diagnóstico , Testes Genéticos/normas , Testes Genéticos/métodos , Feminino , Regiões Promotoras Genéticas/genética , Masculino , Variações do Número de Cópias de DNA/genética , Criança , Adulto , Pré-Escolar , Impressão Genômica/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-38860282

RESUMO

Clinical trials of hypothermia after pediatric cardiac arrest (CA) have not seen robust improvement in functional outcome, possibly because of the long delay in achieving target temperature. Previous work in infant piglets showed that high nasal airflow, which induces evaporative cooling in the nasal mucosa, reduced regional brain temperature uniformly in half the time needed to reduce body temperature. Here, we evaluated whether initiation of hypothermia with high transnasal airflow provides neuroprotection without adverse effects in the setting of asphyxic CA. Anesthetized piglets underwent sham-operated procedures (n=7) or asphyxic CA with normothermic recovery (38.5°C; n=9) or hypothermia initiated by surface cooling at 10 (n=8) or 120 (n=7) minutes or transnasal cooling initiated at 10 (n=7) or 120 (n=7) minutes after resuscitation. Hypothermia was sustained at 34°C with surface cooling until 20 hours followed by 6 hours of rewarming. At four days of recovery, significant neuronal loss occurred in putamen and sensorimotor cortex. Transnasal cooling initiated at 10 minutes significantly rescued the number of viable neurons in putamen, whereas levels in putamen in other hypothermic groups remained less than sham levels. In sensorimotor cortex, neuronal viability in the four hypothermic groups was not significantly different from the sham group. These results demonstrate that early initiation of high transnasal airflow in a pediatric CA model is effective in protecting vulnerable brain regions. Because of its simplicity, portability, and low cost, transnasal cooling potentially could be deployed in the field or emergency room for early initiation of brain cooling after pediatric CA.

12.
J Nutr ; 154(1): 213-223, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37984743

RESUMO

BACKGROUND: Manganese (Mn) is an essential micronutrient, but inadequate or excess Mn intake can have a detrimental impact on human health. Despite the essentiality, little is known about the relationship between Mn and sleep. OBJECTIVE: This study aimed to examine the relationship between blood Mn concentrations and sleep outcomes in US adults. METHODS: This cross-sectional study used data on blood Mn and sleep from the 2017-2020 National Health and Nutrition Examination Survey (NHANES) (n = 8356, age ≥18 y). Multivariable logistic regression was used to examine associations between quintiles of blood Mn concentrations and subjective sleep outcomes (short sleep duration, late sleep midpoint, trouble sleeping, and obstructive sleep apnea [OSA] symptoms), adjusting for age, gender, body mass index, race/ethnicity, income, smoking, inflammation-adjusted serum ferritin concentration (iron status), caffeine, and alcohol intake. Gender-stratified models were used due to interactions with gender. RESULTS: The mean (SE) blood Mn concentration was 9.7 (0.1) µg/L in US adults. In males, a nonlinear association was noted in the relationship between blood Mn levels and short sleep duration on weekdays and weekends. The third Mn quintile (Q3) group had lower odds of short sleep duration (<7 h) on weekdays (odds ratio [OR]=0.6, 95% confidence interval [CI]: 0.4, 0.9) than the lowest Mn quintile (Q1, reference) after adjusting for covariates in males. The second Mn quintile (Q2) group had lower odds of late sleep midpoint on weekdays than Q1 (OR=0.6, 95% CI: 0.4, 0.8). In females, Q2 group had lower odds of OSA symptoms than Q1 (OR: 0.6, 95% CI: 0.4, 0.9). No relationship was noted between Mn and trouble sleeping. CONCLUSIONS: Gender differences exist in the association between Mn and sleep in adults. Q1 group had the poorest sleep outcomes, including higher odds of short sleep duration (in males), late sleep midpoint (in males), and OSA symptoms (in females).


Assuntos
Manganês , Apneia Obstrutiva do Sono , Adulto , Masculino , Feminino , Humanos , Estados Unidos/epidemiologia , Inquéritos Nutricionais , Estudos Transversais , Sono
13.
J Rheumatol ; 51(7): 721-727, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38621797

RESUMO

OBJECTIVE: To determine how serologic responses to coronavirus disease 2019 (COVID-19) vaccination and infection in immune-mediated inflammatory disease (IMID) are affected by time since last vaccination and other factors. METHODS: Post-COVID-19 vaccination, data, and dried blood spots or sera were collected from adults with rheumatoid arthritis, inflammatory bowel disease, systemic lupus erythematosus, ankylosing spondylitis and spondylarthritis, and psoriasis and psoriatic arthritis. The first sample was collected at enrollment, then at 2 to 4 weeks and 3, 6, and 12 months after the latest vaccine dose. Multivariate generalized estimating equation regressions (including medications, demographics, and vaccination history) evaluated serologic response, based on log-transformed anti-receptor-binding domain (RBD) IgG titers; we also measured antinucleocapsid (anti-N) IgG. RESULTS: Positive associations for log-transformed anti-RBD titers were seen with female sex, number of doses, and self-reported COVID-19 infections in 2021 to 2023. Negative associations were seen with prednisone, anti-tumor necrosis factor agents, and rituximab. Over the 2021-2023 period, most (94%) of anti-N positivity was associated with a self-reported infection in the 3 months prior to testing. From March 2021 to February 2022, anti-N positivity was present in 5% to 15% of samples and was highest in the post-Omicron era, with antinucleocapsid positivity trending to 30% to 35% or higher as of March 2023. Anti-N positivity in IMID remained lower than Canada's general population seroprevalence (> 50% in 2022 and > 75% in 2023). Time since last vaccination was negatively associated with log-transformed anti-RBD titers, particularly after 210 days. CONCLUSION: Ours is the first pan-Canadian IMID assessment of how vaccine history and other factors affect serologic COVID-19 vaccine responses. These findings may help individuals personalize vaccination decisions, including consideration of additional vaccination when > 6 months has elapsed since last COVID-19 vaccination/infection.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Feminino , Masculino , COVID-19/prevenção & controle , COVID-19/imunologia , COVID-19/epidemiologia , Pessoa de Meia-Idade , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/uso terapêutico , Adulto , Idoso , SARS-CoV-2/imunologia , Anticorpos Antivirais/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Vacinação , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/sangue , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/sangue
14.
Pediatr Res ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009765

RESUMO

BACKGROUND: Diastolic blood pressure (DBP) is suggested as a surrogate for coronary perfusion pressure (CPP) during cardiopulmonary resuscitation. We examined the correlation between DBP and CPP and hypothesized that both would be associated with survival in a pediatric swine model of asphyxial cardiac arrest. METHODS: We performed a retrospective, secondary analysis of 102 pediatric swine resuscitations. DBP and CPP were recorded every 30 s during resuscitation. Values were compared between survivors and non-survivors. RESULTS: DBP mirrored CPP in survivors and non-survivors throughout resuscitation and both were associated with survival. Improvements in DBP and CPP after the first epinephrine administration were greater in survivors (DBP: 25.1 ± 3.0 vs. 5.4 ± 0.8 mmHg, p < 0.01; CPP: 24.9 ± 3.2 vs. 4.8 ± 0.9 mmHg, p < 0.01). DBP and CPP after epinephrine administration were highly predictive of survival, with an area under the curve of 0.95 (0.89-1.00) for DBP and 0.90 (0.81-0.99) for CPP. The optimal threshold for DBP was 22.5 mmHg, whereas that for CPP was 14.5 mmHg. CONCLUSIONS: DBP and CPP were associated with survival throughout resuscitation, and the response of both to the first epinephrine administration was highly predictive of survival in this model. Clinically, the availability of DBP makes it useful as a target for physiologic feedback during resuscitation. IMPACT: Diastolic blood pressure (DBP) mirrored coronary perfusion pressure (CPP) throughout prolonged resuscitation in a pediatric model of asphyxial cardiac arrest. Mean DBP and CPP were significantly greater in survivors than in non-survivors both before and after administration of epinephrine. The response of both DBP and CPP to the first dose of epinephrine was highly predictive of return of spontaneous circulation. Given the clinical availability of DBP, these findings support its use as a surrogate for CPP to guide high-quality cardiopulmonary resuscitation in this pediatric swine model.

15.
BMC Gastroenterol ; 24(1): 189, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816836

RESUMO

BACKGROUND AND AIMS: There is an incomplete understanding of the full safety profiles of repeated COVID-19 vaccinations in patients with inflammatory bowel disease (IBD). Among individuals with IBD, we assessed whether COVID-19 vaccines were associated with serious adverse events of special interest (AESI) and health care utilization [all-cause hospitalizations, Emergency Department (ED) visits, gastroenterology visits, IBD-related visits]. METHODS: Using comprehensive administrative health data from Ontario, Canada, adults with IBD who received at least one COVID-19 vaccine from December 2020-January 2022 were included. Self-controlled case series analyses were conducted to evaluate the relative incidence rates of AESI and health care utilization outcomes across post-vaccination risk and control periods. RESULTS: Among 88,407 IBD patients, 99.7% received mRNA vaccines and 75.9% received ≥ 3 doses. Relative to control periods, we did not detect an increase in AESI. IBD patients had fewer all-cause hospitalizations during post-vaccination risk periods. Patients experienced more all-cause ED visits after dose 2 [Relative Incidence (RI):1.08(95%CI:1.04-1.12)] but fewer visits after doses 3 [RI:0.85 (95%CI:0.81-0.90)] and 4 [RI:0.73 (95%CI:0.57-0.92)]. There was no increase in gastroenterologist visits or IBD-related health care utilization post-vaccination. There were fewer IBD-related hospitalizations after dose 1 [RI:0.84 (95%CI:0.72-0.98)] and 3 [RI:0.63 (95%CI:0.52-0.76)], fewer IBD-related ED visits after dose 3 [RI:0.81 (95%CI:0.71-0.91)] and 4 [RI:0.55 (95%CI:0.32-0.96)], and fewer outpatient visits after dose 2 [RI:0.91 (95%CI:0.90-0.93)] and 3 [RI:0.87 (95%CI:0.86-0.89)]. CONCLUSION: This population-based study did not detect increased AESI, all-cause or IBD-related health care utilization following COVID-19 vaccination, suggesting a lack of association between vaccination and increased disease activity.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Hospitalização , Doenças Inflamatórias Intestinais , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , COVID-19/prevenção & controle , COVID-19/epidemiologia , Vacinas contra COVID-19/efeitos adversos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Incidência , Ontário/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , SARS-CoV-2 , Vacinação/estatística & dados numéricos , Vacinação/efeitos adversos
16.
Chem Rev ; 122(9): 8758-8808, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35254051

RESUMO

The development of new catalyst materials for energy-efficient chemical synthesis is critical as over 80% of industrial processes rely on catalysts, with many of the most energy-intensive processes specifically using heterogeneous catalysis. Catalytic performance is a complex interplay of phenomena involving temperature, pressure, gas composition, surface composition, and structure over multiple length and time scales. In response to this complexity, the integrated approach to heterogeneous dilute alloy catalysis reviewed here brings together materials synthesis, mechanistic surface chemistry, reaction kinetics, in situ and operando characterization, and theoretical calculations in a coordinated effort to develop design principles to predict and improve catalytic selectivity. Dilute alloy catalysts─in which isolated atoms or small ensembles of the minority metal on the host metal lead to enhanced reactivity while retaining selectivity─are particularly promising as selective catalysts. Several dilute alloy materials using Au, Ag, and Cu as the majority host element, including more recently introduced support-free nanoporous metals and oxide-supported nanoparticle "raspberry colloid templated (RCT)" materials, are reviewed for selective oxidation and hydrogenation reactions. Progress in understanding how such dilute alloy catalysts can be used to enhance selectivity of key synthetic reactions is reviewed, including quantitative scaling from model studies to catalytic conditions. The dynamic evolution of catalyst structure and composition studied in surface science and catalytic conditions and their relationship to catalytic function are also discussed, followed by advanced characterization and theoretical modeling that have been developed to determine the distribution of minority metal atoms at or near the surface. The integrated approach demonstrates the success of bridging the divide between fundamental knowledge and design of catalytic processes in complex catalytic systems, which can accelerate the development of new and efficient catalytic processes.


Assuntos
Ligas , Óxidos , Catálise , Domínio Catalítico , Metais , Oxirredução , Óxidos/química
17.
Gastric Cancer ; 27(2): 375-386, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38281295

RESUMO

BACKGROUND: Rivoceranib is an oral, selective tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2. ANGEL (NCT03042611) was a global, randomized, double-blinded, placebo-controlled, phase 3 study evaluating rivoceranib as 3rd-line or ≥4th-line therapy in patients with advanced/metastatic gastric or gastroesophageal junction (GEJ) cancer. METHODS: Patients had failed ≥2 lines of chemotherapy and were randomized 2:1 to rivoceranib 700 mg once daily or placebo with best supportive care. PRIMARY ENDPOINT: overall survival (OS) in the intention-to-treat population. Secondary endpoints: progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR) by blinded independent central review (BICR). RESULTS: In total, 460 patients (rivoceranib n = 308, placebo n = 152) were enrolled. OS was not statistically different for rivoceranib versus placebo (median 5.78 vs. 5.13 months; hazard ratio [HR] 0.93, 95% CI 0.74-1.15; p = 0.4724). PFS by BICR (median 2.83 vs. 1.77 months; HR 0.58, 95% CI 0.47-0.71; p < 0.0001), ORR (6.5% vs. 1.3%; p = 0.0119), and DCR (40.3 vs. 13.2%; p < 0.0001) were improved with rivoceranib versus placebo. In patients receiving ≥4th-line therapy, OS (median 6.34 vs. 4.73 months; p = 0.0192) and PFS by BICR (median 3.52 vs. 1.71 months; p < 0.0001) were improved with rivoceranib versus placebo. The most common grade ≥ 3 treatment-emergent adverse events with rivoceranib were hypertension (17.9%), anemia (10.4%), aspartate aminotransferase increased (9.4%), asthenia (8.5%), and proteinuria (7.5%). CONCLUSIONS: This study did not meet its primary OS endpoint. Compared to placebo, rivoceranib improved PFS, ORR, and DCR. Rivoceranib also improved OS in a prespecified patient subgroup receiving ≥4th-line therapy.


Assuntos
Piridinas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Junção Esofagogástrica/patologia , Método Duplo-Cego
18.
Curr Psychiatry Rep ; 26(5): 229-239, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38700836

RESUMO

PURPOSE OF REVIEW: The goal of this paper was to highlight the degree to which sleep, behavioral health, and leader involvement were interrelated using data from militaries in five English-speaking countries: Australia, Canada, New Zealand, the UK, and the United States. RECENT FINDINGS: Many service members reported sleeping fewer than the recommended 7 h/night: 34.9%, 67.2%, and 77.2% of respondents from New Zealand, Canada, and the United States, respectively. Countries reporting shorter sleep duration also reported fewer insomnia-related difficulties, likely reflecting higher sleep pressure from chronic sleep loss. Across all countries, sleep problems were positively correlated with behavioral health symptoms. Importantly, leader promotion of healthy sleep was positively correlated with more sleep and negatively correlated with sleep problems and behavioral health symptoms. Insufficient sleep in the military is ubiquitous, with serious implications for the behavioral health and functioning of service members. Leaders should attend to these risks and examine ways to promote healthy sleep in service members.


Assuntos
Militares , Humanos , Militares/estatística & dados numéricos , Militares/psicologia , Nova Zelândia , Estados Unidos/epidemiologia , Austrália/epidemiologia , Canadá/epidemiologia , Reino Unido/epidemiologia , Privação do Sono , Liderança
19.
Anesth Analg ; 138(5): 1020-1030, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37115722

RESUMO

BACKGROUND: Increasing clinical demands can adversely impact academic advancement, including the ability to deliver lectures and disseminate scholarly work. The virtual lecture platform became mainstream during the height of the coronavirus-19 pandemic. Lessons learned from this period may offer insight into supporting academic productivity among physicians who must balance multiple demands, including high clinical workloads and family care responsibilities. We evaluated perceptions on delivering virtual lectures to determine whether virtual venues merit continuation beyond the pandemic's initial phase and whether these perceptions differ by gender and rank. METHODS: In a survey study, faculty who spoke in 1 of 3 virtual lecture programs in the Departments of Anesthesiology and Critical Care Medicine, Otolaryngology, and Radiology at a university hospital in 2020 to 2022 were queried about their experience. Speakers' motivations to lecture virtually and the perceived advantages and disadvantages of virtual and in-person lectures were analyzed using descriptive statistics and qualitative analyses. RESULTS: Seventy-two of 95 (76%) faculty members responded (40% women, 38% men, and 22% gender undisclosed). Virtual lectures supported the speakers "a lot" to "extremely" with the following goals: enhancing one's reputation and credibility (76%), networking (70%), receiving feedback (63%), and advancing prospects for promotion (59%). Virtual programs also increased the speakers' sense of accomplishment (70%) and professional optimism (61%) by at least "a lot," including instructors and assistant professors who previously had difficulty obtaining invitations to speak outside their institution. Many respondents had declined prior invitations to speak in-person due to clinical workload (66%) and family care responsibilities (58%). Previous opportunities to lecture in-person were also refused due to finances (39%), teaching (26%), and research (19%) requirements, personal medical conditions or disabilities (9%), and religious obligations (5%). Promotion was a stronger motivating factor to lecture virtually for instructors and assistant professors than for associate and full professors. By contrast, disseminating work and ideas was a stronger motivator for associate and full professors. Associate and full professors also reported greater improvement in work-related well-being than earlier career faculty from the virtual lecture experience. Very few differences were found by gender. CONCLUSIONS: Virtual lecture programs support faculty who might not otherwise have the opportunity to lecture in-person due to multiple constraints. To increase the dissemination of scholarly work and expand opportunities to all faculty, virtual lectures should continue even as in-person venues are reestablished.


Assuntos
Anestesiologia , Médicos , Masculino , Humanos , Feminino , Docentes de Medicina , Inquéritos e Questionários , Mobilidade Ocupacional
20.
Pediatr Crit Care Med ; 25(4): e193-e204, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38059739

RESUMO

OBJECTIVES: Sedation and analgesia for infants and children requiring mechanical ventilation in the PICU is uniquely challenging due to the wide spectrum of ages, developmental stages, and pathophysiological processes encountered. Studies evaluating the safety and efficacy of sedative and analgesic management in pediatric patients have used heterogeneous methodologies. The Sedation Consortium on Endpoints and Procedures for Treatment, Education, and Research (SCEPTER) IV hosted a series of multidisciplinary meetings to establish consensus statements for future clinical study design and implementation as a guide for investigators studying PICU sedation and analgesia. DESIGN: Twenty-five key elements framed as consensus statements were developed in five domains: study design, enrollment, protocol, outcomes and measurement instruments, and future directions. SETTING: A virtual meeting was held on March 2-3, 2022, followed by an in-person meeting in Washington, DC, on June 15-16, 2022. Subsequent iterative online meetings were held to achieve consensus. SUBJECTS: Fifty-one multidisciplinary, international participants from academia, industry, the U.S. Food and Drug Administration, and family members of PICU patients attended the virtual and in-person meetings. Participants were invited based on their background and experience. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Common themes throughout the SCEPTER IV consensus statements included using coordinated multidisciplinary and interprofessional teams to ensure culturally appropriate study design and diverse patient enrollment, obtaining input from PICU survivors and their families, engaging community members, and using developmentally appropriate and validated instruments for assessments of sedation, pain, iatrogenic withdrawal, and ICU delirium. CONCLUSIONS: These SCEPTER IV consensus statements are comprehensive and may assist investigators in the design, enrollment, implementation, and dissemination of studies involving sedation and analgesia of PICU patients requiring mechanical ventilation. Implementation may strengthen the rigor and reproducibility of research studies on PICU sedation and analgesia and facilitate the synthesis of evidence across studies to improve the safety and quality of care for PICU patients.


Assuntos
Analgesia , Estado Terminal , Lactente , Criança , Humanos , Estado Terminal/terapia , Reprodutibilidade dos Testes , Analgesia/métodos , Dor , Respiração Artificial , Hipnóticos e Sedativos/uso terapêutico
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