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1.
Nature ; 634(8036): 1204-1210, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39385023

RESUMO

Multivesicular bodies are key endosomal compartments implicated in cellular quality control through their degradation of membrane-bound cargo proteins1-3. The ATP-consuming ESCRT protein machinery mediates the capture and engulfment of membrane-bound cargo proteins through invagination and scission of multivesicular-body membranes to form intraluminal vesicles4,5. Here we report that the plant ESCRT component FREE16 forms liquid-like condensates that associate with membranes to drive intraluminal vesicle formation. We use a minimal physical model, reconstitution experiments and in silico simulations to identify the dynamics of this process and describe intermediate morphologies of nascent intraluminal vesicles. Furthermore, we find that condensate-wetting-induced line tension forces and membrane asymmetries are sufficient to mediate scission of the membrane neck without the ESCRT protein machinery or ATP consumption. Genetic manipulation of the ESCRT pathway in several eukaryotes provides additional evidence for condensate-mediated membrane scission in vivo. We find that the interplay between condensate and machinery-mediated scission mechanisms is indispensable for osmotic stress tolerance in plants. We propose that condensate-mediated scission represents a previously undescribed scission mechanism that depends on the physicomolecular properties of the condensate and is involved in a range of trafficking processes. More generally, FREE1 condensate-mediated membrane scission in multivesicular-body biogenesis highlights the fundamental role of wetting in intracellular dynamics and organization.


Assuntos
Arabidopsis , Complexos Endossomais de Distribuição Requeridos para Transporte , Endossomos , Membranas Intracelulares , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/química , Endossomos/metabolismo , Arabidopsis/metabolismo , Membranas Intracelulares/metabolismo , Condensados Biomoleculares/metabolismo , Condensados Biomoleculares/química , Corpos Multivesiculares/metabolismo , Pressão Osmótica , Trifosfato de Adenosina/metabolismo
2.
Inorg Chem ; 63(33): 15340-15347, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39106318

RESUMO

Electrochemical ion exchange has recently been demonstrated to be a unique method for the preparation of novel cathode materials, which cannot be accessible by traditional direct synthesis routes. In this study, the vanadium borophosphate compound K1.33Na0.67[VO(B2O)(PO4)2(HPO4)]·1.63H2O (KNVBP) with zeolitic framework exhibits fast electrochemical Na+/K+ ion exchange when used as cathode material in sodium-ion batteries (SIBs). Ex situ structural analyses and electrochemical measurements confirm that most of the K+ ions in the parent KNVBP can be extracted and exchanged by Na+ ions after the first charge/discharge cycle. The in situ-generated Na-rich phase shows reversible electrochemical activity at approximately 3.9 V versus Na+/Na with a specific capacity of 52.9 mAh g-1, comparable to 96.2% of the theoretical capacity. Moreover, enhanced ionic diffusion kinetics can be achieved after the Na+/K+ exchange. This study provides a valuable insight into the electrochemical ion exchange in polyanion compounds toward application in metal-ion batteries.

3.
Sex Transm Dis ; 50(8): 485-489, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37155638

RESUMO

BACKGROUND: Public release of health data typically requires statistical disclosure limitation (SDL), but scant research demonstrates how real-world SDL affects data usability. Recent changes of federal data re-release policy allow a pseudo-counterfactual comparison of HIV and syphilis data suppression rules. METHODS: Incident counts (2019) of HIV and syphilis infections by county for Black and White populations were downloaded from the US Centers for Disease Control and Prevention. We quantified and compared suppression status by disease and county between Black and White populations and calculated incident rate ratios for counties with statistically reliable counts. RESULTS: Approximately 50% of US counties have incident HIV counts suppressed for Black and White populations compared with only 5% for syphilis, which has an alternative suppression strategy. The county population sizes protected by a numerator disclosure rule (<4) spans several orders of magnitude. Calculations of incident rate ratios, used as a measure of health disparity, were impossible in the 220 counties most susceptible to an HIV outbreak. CONCLUSIONS: Balancing tradeoffs between providing and protecting data are key to health initiatives worldwide. We encourage an increase in empirical research on the impact of SDL, especially in the context of health disparities, and recommend new approaches to avoid the "oppression of data suppression."


Assuntos
Segurança Computacional , Infecções por HIV , Sífilis , Humanos , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Sífilis/epidemiologia , Sífilis/prevenção & controle , Estados Unidos/epidemiologia , Brancos , Negro ou Afro-Americano , Revelação/legislação & jurisprudência
4.
Int J Mol Sci ; 24(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37047424

RESUMO

At present, the development and usage of degradable plastics instead of traditional plastics is an effective way to solve the pollution of marine microplastics. Poly (butylene adipate-co-terephthalate) (PBAT) is known as one of the most promising biodegradable materials. Nevertheless, the degradation rate of PBAT in water environment is slow. In this work, we successfully prepared four kinds of high molecular weight polyester copolyesters (PBATGA) via quaternary copolymerization. The results showed that the intrinsic viscosity of PBATGA copolymers ranged from 0.74 to 1.01 dL/g with a glycolic acid content of 0-40%. PBATGA copolymers had excellent flexibility and thermal stability. The tensile strength was 5~40 MPa, the elongation at break was greater than 460%, especially the elongation at break of PBATGA10 at 1235%, and the thermal decomposition temperature of PBATGA copolyesters was higher than 375 °C. It was found that PBATGA copolyester had a faster hydrolysis rate than PBAT, and the weight loss of PBATGA copolymers showed a tendency of pH = 12 > Lipase ≈ pH = 7 > pH = 2. The quaternary polymerization of PBAT will have the advantage of achieving industrialization, unlike the previous polymerization process. In addition, the polymerization of PBATGA copolyesters not only utilizes the by-products of the coal chemical industry, but also it can be promising in the production of biodegradable packaging to reduce marine plastic pollution.


Assuntos
Plásticos , Poliésteres , Polimerização , Poliésteres/química , Polímeros , Adipatos
5.
Plant Mol Biol ; 110(1-2): 1-12, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35644016

RESUMO

KEY MESSAGE: AtTIP1 physically and genetically interacts with AtCESA3. AtCESA3 undergoes S-acylation, possibly mediated by AtTIP1, suggesting a specific role of AtTIP1 in cellulose biosynthesis and plant development. S-acylation is a reversible post-translational lipid modification of proteins catalyzed by protein S-acyl transferases (PATs). S-acylation is important for various biological molecular mechanisms including cellulose biosynthesis. Cellulose is synthesized by the cellulose synthase A (CESA) complexes (CSCs) at the plasma membrane. However, specific PAT involving in cellulose biosynthesis has not been identified and the precise mechanism by which PAT regulates the CESAs is largely unknown. Here, we report isolation of tip1-5, an allele of Tip Growth Defective1 (AtTIP1/AtPAT24) with a premature stop codon. tip1-5 genetically interacts with ixr1-2, a point mutant of AtCESA3 which encodes a catalytic subunit of CSC synthesizing primary wall cellulose. We show that AtTIP1 physically interacts with AtCESA3. AtCESA3 undergoes S-acylation, which is possibly mediated by AtTIP1, suggesting a functional relationship between AtTIP1 and AtCESA3. Moreover, the interfascicular fiber cells in the primary inflorescence stems of tip1-5 ixr1-2 double mutant contain thinner cell walls and significantly less crystalline cellulose compared to the single mutants. These results highlight the positive regulation of AtTIP1 in cellulose biosynthesis, and a specific role of AtPAT in plant development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Celulose/metabolismo , Glucosiltransferases/metabolismo
6.
Am J Obstet Gynecol ; 227(2): 263.e1-263.e38, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35032444

RESUMO

BACKGROUND: Prevention of prenatal exposures to teratogenic drugs is a significant clinical and public health concern. With the enactment of the US Food and Drug Administration Amendments Act in 2007, the US Food and Drug Administration has begun to require manufacturers to implement Risk Evaluation and Mitigation Strategies to prevent prenatal exposures. Among 12 risk evaluation and mitigation strategy drugs, several had predecessor risk mitigation plans (eg, isotretinoin) and some were newly required (eg, mycophenolate). Only a small proportion of teratogenic drugs are currently subject to Risk Evaluation and Mitigation Strategies, and the extent of prenatal exposure to the universe of teratogenic drugs compared with drugs subject to Risk Evaluation and Mitigation Strategies is unknown. Moreover, the effectiveness of such advanced risk mitigation programs in preventing prenatal exposure is not clear. OBJECTIVE: This study aimed to characterize the epidemiology of prenatal exposures to definite and potential teratogens during the risk evaluation and mitigation strategy era. STUDY DESIGN: We constructed a time-series of pregnancies identified from a national private insurance claims database (IBM MarketScan) to estimate prenatal exposures to teratogenic drugs (2006-2017). Pregnancy outcomes, gestational age, and the onset of pregnancy were determined with previously validated algorithms. The Teratology Information Service and Clinical Pharmacology databases were used to identify drugs with definite (n=141) or potential (n=65) teratogenic effects, and drugs with debatable risks such as benzodiazepines, statins, tetracyclines, sex hormones, infertility treatments, and gonadotropin-releasing hormone analogs were excluded. We defined prenatal exposure as ≥1 prescription fill or medical encounter involving administration of drugs with a definite teratogenic risk (including 12 for which there is a "current or discontinued" risk evaluation and mitigation strategy) or a potential teratogenic risk. We evaluated secular trends and modeled the effects of age, preconception exposure, and state healthcare quality rankings on prenatal exposure, adjusting for demographic factors and clinical conditions. RESULTS: The cohort included 3,445,612 pregnancies (2,532,444 live deliveries). Prenatal exposures to definite teratogens decreased slightly during the study years from 1.86 to 1.24 per 100 pregnancies between 2006 and 2017, whereas exposure increased for potential teratogens from 3.40% to 5.33%. Prenatal exposure prevalences were higher during the first trimester and for pregnancies that ended in nonlive outcomes. Drugs subject to Risk Evaluation and Mitigation Strategies had low background utilization and contributed to a small proportion of prenatal exposures (15.1 per 100,000 pregnancies). We also observed fewer prenatal exposures to risk evaluation and mitigation strategy drugs among women of childbearing age who used these treatments (0.14% vs 0.36% for any definite teratogen). Age extremes and low state-level healthcare quality rankings were independent predictors of prenatal exposure. CONCLUSION: Fetuses in more than 1 in 16 pregnancies continued to be exposed to teratogenic drugs during the past decade. Drugs with Risk Evaluation and Mitigation Strategies imposed a small burden of prenatal exposure because of the low background utilization rates and lower pregnancy prevalence among women of childbearing age who used these drugs. Although the declining exposure rates to teratogenic drugs with definite risk are encouraging, the rising prenatal exposure to drugs with potential risk calls for more assessments. Future research is needed to elucidate the health outcomes of fetuses exposed to potential risk drugs, understand the effectiveness of risk evaluation and mitigation strategy programs, and prioritize teratogenic drugs for advanced risk mitigation.


Assuntos
Anormalidades Induzidas por Medicamentos , Efeitos Tardios da Exposição Pré-Natal , Teratogênese , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Induzidas por Medicamentos/etiologia , Anormalidades Induzidas por Medicamentos/prevenção & controle , Feminino , Humanos , Gravidez , Resultado da Gravidez , Avaliação de Risco e Mitigação , Teratogênicos
7.
Pain Med ; 23(7): 1323-1332, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34931686

RESUMO

BACKGROUND: "Doctor shopping" typically refers to patients that seek controlled substance prescriptions from multiple providers with the presumed intent to obtain these medications for non-medical use and/or diversion. The purpose of this scoping review is to document and examine the criteria used to identify "doctor shopping" from dispensing data in the United States. METHODS: A scoping review was conducted on "doctor shopping" or analogous terminology from January 1, 2000, through December 31, 2020, using the Web of Science Core Collection (seven citation indexes). Our search was limited to the United States only, English-language, peer-reviewed and US federal government studies. Studies without explicit "doctor shopping" criteria were excluded. Key components of these criteria included the number of prescribers and dispensers, dispensing period, and drug class (e.g., opioids). RESULTS: Of 9,845 records identified, 95 articles met the inclusion criteria and our pool of studies ranged from years 2003 to 2020. The most common threshold-based or count definition was (≥4 Prescribers [P] AND ≥4 Dispensers [D]) (n = 12). Thirty-three studies used a 365-day detection window. Opioids alone were studied most commonly (n = 69), followed by benzodiazepines and stimulants (n = 5 and n = 2, respectively). Only 39 (41%) studies provided specific drug lists with active ingredients. CONCLUSION: Relatively simple P x D criteria for identifying "doctor shopping" are still the dominant paradigm with the need for ongoing validation. The value of P x D criteria may change through time with more diverse methods applied to dispensing data emerging.


Assuntos
Analgésicos Opioides , Médicos , Analgésicos Opioides/uso terapêutico , Benzodiazepinas , Substâncias Controladas , Humanos , Prescrições , Estados Unidos
8.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232379

RESUMO

The main problem of manufacturing with traditional biodegradable plastics is that it is more expensive than manufacturing with polymers derived from petroleum, and the application scope is currently limited due to poor comprehensive performance. In this study, a novel biodegradable poly(butylene adipic acid/terephthalate-co-glycolic acid) (PBATGA) copolyester with 25-60% glycolic acid units was successfully synthesized by esterification and polycondensation using cheap coal chemical byproduct methyl glycolate instead of expensive glycolic acid. The structure of the copolyester was characterized by ATR-FTIR, 1H NMR, DSC, and XRD; and its barrier property, water contact angle, heat resistance, and mechanical properties were tested. According to the experiment result, the PBATGA copolyesters showed improved oxygen (O2) and water vapor barrier character, and better hydrophilicity when compared with PBAT. The crystallization peaks of PBATGAs were elevated from 64 °C to 77 °C when the content of the GA unit was 25 mol %, meanwhile, the elongation at the break of PBATGA25 was more than 1300%. These results indicate that PBATGA copolyesters have good potentiality in high O2 and water vapor barrier and degradable packaging material.


Assuntos
Plásticos Biodegradáveis , Petróleo , Adipatos , Alcenos , Carvão Mineral , Glicolatos , Oxigênio , Ácidos Ftálicos , Poliésteres/química , Polímeros/química , Vapor
9.
Plant J ; 104(6): 1617-1634, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058303

RESUMO

The highly conserved endosomal sorting complex required for transport (ESCRT) pathway plays critical roles in endosomal sorting of ubiquitinated plasma membrane proteins for degradation. However, the functions of many components of the ESCRT machinery in plants remain unsolved. Here we show that the ESCRT-I subunits VPS28A and VPS28B are functionally redundant and required for embryonic development in Arabidopsis. We conducted a screen for genetic enhancers of pid, which is defective in auxin signaling and transport. We isolated a no--cotyledon in pid 104 (ncp104) mutant, which failed to develop cotyledons in a pid background. We discovered that ncp104 was a unique recessive gain-of-function allele of vps28a. VPS28A and VPS28B were expressed during embryogenesis and the proteins were localized to the trans-Golgi network/early endosome and post-Golgi/endosomal compartments, consistent with their functions in endosomal sorting and embryogenesis. The single vps28a and vps28b loss-of-function mutants did not display obvious developmental defects, but their double mutants showed abnormal cell division patterns and were arrested at the globular embryo stage. The vps28a vps28b double mutants showed altered auxin responses, disrupted PIN1-GFP expression patterns, and abnormal PIN1-GFP accumulation in small aberrant vacuoles. The ncp104 mutation may cause the VPS28A protein to become unstable and/or toxic. Taken together, our findings demonstrate that the ESCRT-I components VPS28A and VPS28B redundantly play essential roles in vacuole formation, endosomal sorting of plasma membrane proteins, and auxin-mediated plant development.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Complexos Endossomais de Distribuição Requeridos para Transporte/fisiologia , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/fisiologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Cotilédone/crescimento & desenvolvimento , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Mutação com Perda de Função , Reguladores de Crescimento de Plantas/metabolismo , Sementes/crescimento & desenvolvimento
10.
BMC Plant Biol ; 21(1): 542, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800993

RESUMO

BACKGROUND: Rice is a crop that is very sensitive to low temperature, and its morphological development and production are greatly affected by low temperature. Therefore, understanding the genetic basis of cold tolerance in rice is of great significance for mining favorable genes and cultivating excellent rice varieties. However, there have been limited studies focusing on cold tolerance at the bud burst stage; therefore, considerable attention should be given to the genetic basis of cold tolerance at this stage. RESULTS: In this study, a natural population consisting of 211 rice landraces collected from 15 provinces in China and other countries was used for the first time to evaluate cold tolerance at the bud burst stage. Population structure analysis showed that this population was divided into two groups and was rich in genetic diversity. Our evaluation results confirmed that japonica rice was more tolerant to cold at the bud burst stage than indica rice. A genome-wide association study (GWAS) was performed with the phenotypic data of 211 rice landraces and a 36,727 SNP dataset under a mixed linear model. Twelve QTLs (P < 0.0001) were identified for the seedling survival rate (SR) after treatment at 4 °C, in which there were five QTLs (qSR2-2, qSR3-1, qSR3-2, qSR3-3 and qSR9) that were colocalized with those from previous studies and seven QTLs (qSR2-1, qSR3-4, qSR3-5, qSR3-6, qSR3-7, qSR4 and qSR7) that were reported for the first time. Among these QTLs, qSR9, harboring the most significant SNP, explained the most phenotypic variation. Through bioinformatics analysis, five genes (LOC_Os09g12440, LOC_Os09g12470, LOC_Os09g12520, LOC_Os09g12580 and LOC_Os09g12720) were identified as candidates for qSR9. CONCLUSION: This natural population consisting of 211 rice landraces combined with high-density SNPs will serve as a better choice for identifying rice QTLs/genes in the future, and the detected QTLs associated with cold tolerance at the bud burst stage in rice will be conducive to further mining favorable genes and breeding rice varieties under cold stress.


Assuntos
Temperatura Baixa , Resposta ao Choque Frio/genética , Flores/crescimento & desenvolvimento , Flores/genética , Oryza/crescimento & desenvolvimento , Oryza/genética , Locos de Características Quantitativas/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo
11.
New Phytol ; 231(2): 713-725, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33876422

RESUMO

Phosphoinositides play important roles in plant growth and development. Several SAC domain phosphoinositide phosphatases have been reported to be important for plant development. Here, we show functional analysis of SUPPRESSOR OF ACTIN 6 (SAC6) to SAC8 in Arabidopsis, a subfamily of phosphoinositide phosphatases containing SAC-domain and two transmembrane motifs. We isolated an Arabidopsis mutant ncp2 that lacked cotyledons in seedling and embryo in pid, a background defective in auxin signaling and transport. NCP2 encodes RHD4/SAC7 phosphoinositide phosphatase. SAC6, SAC7 and SAC8 exhibit overlapping and specific expression patterns in seedling and embryo. The sac6 sac7 embryos either fail to develop into seeds, or have three or four cotyledons. The embryo development of sac7 sac8 and sac6 sac7 sac8 mutants is significantly delayed or lethal, and the seedlings are arrested at early stages. Auxin maxima are decreased in double and triple sac mutants. The contents of PtdIns4P and PtdIns(4,5)P2 in sac6 sac7 and sac7 sac8 mutants are dramatically increased. Protein trafficking of the plasma membrane (PM)-localized protein PIN1 and PIN2 from trans-Golgi network/early endosome back to PM is delayed in sac7 sac8 mutants. These results indicate that SAC6-SAC8 are essential for maintaining homeostasis of PtdIns4P and PtdIns(4,5)P2, and auxin-mediated development in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Homeostase , Fosfatidilinositol 4,5-Difosfato , Fosfatos de Fosfatidilinositol , Fosfatidilinositóis , Fosfatases de Fosfoinositídeos
12.
MMWR Morb Mortal Wkly Rep ; 69(5): 125-129, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32027630

RESUMO

Increased prevalence of illicitly manufactured fentanyl and fentanyl analogs has contributed substantially to overdose deaths in the United States (1-3). On October 26, 2015, CDC issued a Health Advisory regarding rapid increases in deaths involving fentanyl. This CDC Health Advisory has been updated twice to address increases in fentanyl and fentanyl analog overdoses and their co-occurrence with nonopioids (4). Deaths involving carfentanil, an analog reportedly 10,000 times more potent than morphine and 100 times more potent than fentanyl, were first reported in Florida, Michigan, and Ohio in 2016 and described in an August 2016 CDC Health Advisory (1,5). Carfentanil is used to rapidly immobilize large animals in veterinary medicine and has no U.S. approved therapeutic use in humans. Carfentanil's street price per dose is likely lower than that of heroin. During 2016 and 2017, an outbreak of carfentanil-involved fatal overdoses in Florida emerged, and the Medical Examiner jurisdiction serving Sarasota, Manatee, and DeSoto counties (the Sarasota area) was the outbreak epicenter. This report describes toxicology profiles, sociodemographic information, and geographic distributions of carfentanil-involved fatal overdoses (carfentanil deaths) in the Sarasota area compared with those in the rest of Florida (i.e., all Florida counties excluding Sarasota area) from January 2016 to December 2017. The Sarasota area accounted for 19.0% of 1,181 statewide carfentanil deaths that occurred during this time and experienced a peak in carfentanil deaths preceding the larger Florida outbreak. The report of a single carfentanil death from August to December 2017 (compared with 73 reported deaths during the same period in 2016) appeared to mark the end of the outbreak in the area. The threat of such rapid, intense fatal overdose outbreaks highlights the need for accelerated reporting, reliable data sharing systems, and novel proactive surveillance to support targeted prevention and response efforts by public health and safety organizations (6).


Assuntos
Surtos de Doenças , Overdose de Drogas/mortalidade , Fentanila/análogos & derivados , Adulto , Feminino , Fentanila/intoxicação , Florida/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade
13.
Biometrics ; 75(2): 603-612, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30430541

RESUMO

In recent years, there has been increased interest in symbolic data analysis, including for exploratory analysis, supervised and unsupervised learning, time series analysis, etc. Traditional statistical approaches that are designed to analyze single-valued data are not suitable because they cannot incorporate the additional information on data structure available in symbolic data, and thus new techniques have been proposed for symbolic data to bridge this gap. In this article, we develop a regularized convex clustering approach for grouping histogram-valued data. The convex clustering is a relaxation of hierarchical clustering methods, where prototypes are grouped by having exactly the same value in each group via penalization of parameters. We apply two different distance metrics to measure (dis)similarity between histograms. Various numerical examples confirm that the proposed method shows better performance than other competitors.


Assuntos
Análise por Conglomerados , Gráficos por Computador , Interpretação Estatística de Dados , Inteligência Artificial
14.
Blood Press ; 28(3): 191-198, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30896317

RESUMO

PURPOSE: Since the publication of the 2017 ACC/AHA hypertension guideline, few studies have analyzed the epidemiology and management of hypertension across many heterogeneous subgroups in the US. MATERIALS AND METHODS: We analyzed the data collected by the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2016. Participants greater than 20 years of age, who had valid blood pressure measurements, were included in the study. A comprehensive analysis of 14 population subgroups was done to systematically examine how hypertension awareness, treatment, and control varied by subpopulations. RESULTS: Our study included 45,557 participants with a mean age of 47.1 years, 48.3% were male and 51.7% were female. 47.8% participants had hypertension, of which 59.9% were aware of their diagnosis. Among the participants who were aware of their hypertension, 90.3% were prescribed medication(s) to lower blood pressure, of which 39.2% had achieved control. Multivariate analysis showed age, gender, Race/ethnicity, annual family income, education level, BMI, waist to height ratio, diabetes, and previous cardiovascular events to be independent risk factors for hypertension. Lower likelihoods of awareness and treatment were associated with male sex, younger age, Mexican ethnicity, participants without health insurance, absence of previous cardiovascular events, diabetes, obesity, or smoking. Overall, hypertension control rate was suboptimal across most of subgroups (<40%). CONCLUSION: Based on the 2017 ACC/AHA guideline, almost half of the US adult population has hypertension. The suboptimal number of people with controlled blood pressure is pervasive in all subgroups and warrants greater efforts in prevention, as well as more effective treatment.


Assuntos
Guias como Assunto , Hipertensão/epidemiologia , Inquéritos Nutricionais , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Estados Unidos
15.
Ann Allergy Asthma Immunol ; 120(3): 272-277.e1, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29398244

RESUMO

BACKGROUND: Race and ethnicity have been shown to influence fractional exhaled nitric oxide (FeNO). There is a need to investigate cutoff points for different races and ethnicities to improve clinical application. OBJECTIVE: To investigate cutoff points for different races and ethnicities by analyzing the FeNO data collected by the National Health and Nutrition Examination Survey from 2007 to 2012. METHODS: This study included 23,433 participants. After excluding participants with confounding factors, 11,084 participants were eligible for data analysis. Based on age and the probability of having allergic airway inflammation, participants were divided into 4 groups. The geometric mean and 5th, 50th, and 95th percentiles of FeNO in Hispanic, white, black, and other races were analyzed in all groups. RESULTS: Compared with white participants, the geometric mean for FeNO in black participants was 36% to 41% higher in children and 5% to 8% higher in adults. Hispanic children had significantly higher FeNO values (14% to 19%) compared with non-Hispanic white children; however, those differences were not significant in adults. Other races had significantly higher FeNO values in children (24-54%) and adults (9-29%) compared with white participants. Further, for normal healthy black children, the 95th percentile was 40.2 parts per billion (ppb), which is significantly higher than the cutoff point recommended by current guidelines. CONCLUSION: Although there are significant differences in FeNO values among races and ethnicities, the current cutoff point at 50 ppb is sufficient to separate healthy from asthmatic populations in adults. However, for black children, we suggest increasing the cutoff point from 35 to 40 ppb to avoid unnecessary diagnosis and treatment.


Assuntos
Asma/etnologia , Asma/metabolismo , Óxido Nítrico/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Etnicidade , Expiração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Grupos Raciais , Estados Unidos , Adulto Jovem
16.
Water Sci Technol ; 77(1-2): 204-210, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29339619

RESUMO

The dewaterability of excess sludge significantly improved upon pretreatment with Fenton's reagent in this study. After 0.9 g/L of Fe2+ and 5.0 g/L of H2O2 were added to the sludge, and reacted for 2 h at pH = 4, the specific resistance to filtration (SRF) of the excess sludge decreased from an initial value of 29.74 × 1012 m/kg to 6.49 × 1012 m/kg. The factors that affected this improvement in sludge dewaterability as evaluated by SRF reduction showed the following order: H2O2 > pH > Fe2+ > reaction time. Furthermore, the hydrolysis performance of the sludge under the optimal reaction conditions was investigated. The results indicated that the concentration of soluble chemical oxygen demand in the supernatant increased almost 14 times compared to raw sludge, and the contents of soluble protein and soluble polysaccharide were more than 8 and 17 times higher, respectively, than for the untreated situation. However, the amounts of ammonia nitrogen (NH4+-N) and phosphate (PO43--P) released from the sludge showed different trends: NH4+-N increased by 200%, while PO43--P decreased by 82%. The production of volatile fatty acids (VFAs) from the treated sludge showed that total VFAs increased by 66%, and iso-butylacetic acid was the dominant product among the total VFAs.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Esgotos/química , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , China , Dessecação , Filtração , Concentração de Íons de Hidrogênio , Hidrólise
17.
Am J Public Health ; 107(5): 812-814, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28323460

RESUMO

OBJECTIVES: To investigate the effects of precursor chemical regulation aimed at reducing cocaine production on cocaine-related maternal and newborn hospital stays in the United States. METHODS: We analyzed monthly counts of maternal and neonatal stays from January 2002 through December 2013 by using a quasi-experimental interrupted time series design. We estimated the preregulation linear trend, postregulation change in linear trend, and abrupt change in level. RESULTS: The number of monthly cocaine-related maternal and neonatal stays decreased by 221 and 128 stays, respectively, following the cocaine precursor regulation change. We also observed a further decline in per-month maternal and neonatal stays of 18 and 8 stays, respectively. CONCLUSIONS: A supply-side disruption in the United States cocaine market was associated with reduced hospital stays for 2 vulnerable populations: pregnant women and newborns. Results support findings that federal precursor regulation can positively reduce cocaine availability in the United States.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/prevenção & controle , Cocaína/provisão & distribuição , Tempo de Internação/legislação & jurisprudência , Tempo de Internação/estatística & dados numéricos , Complicações na Gravidez/prevenção & controle , Adulto , Saúde da Criança , Transtornos Relacionados ao Uso de Cocaína/epidemiologia , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações na Gravidez/epidemiologia , Estados Unidos/epidemiologia
18.
Arterioscler Thromb Vasc Biol ; 36(5): 810-816, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26988589

RESUMO

OBJECTIVE: Increased plasma concentrations of angiotensin II (Ang II) have been implicated in many cardiovascular diseases, such as atherosclerosis, aortic aneurysms, and myocardial infarction, in humans. However, it is not known whether high levels of plasma Ang II affect coronary plaque stability and subsequent myocardial infarction. This study was designed to examine whether elevated plasma Ang II can directly induce coronary events, such as acute coronary syndrome. APPROACH AND RESULTS: To examine the above hypothesis, we infused Ang II (100 ng/min per kg [low group] and 200 ng/min per kg [high group]) or saline vehicle via osmotic minipumps into Watanabe heritable hyperlipidemic rabbits, a model of human familial hypercholesterolemia and atherosclerosis. Infusion of Ang II resulted in mortality rates of 50% and 92% in the low- and high-Ang II groups, respectively, whereas there were no deaths in the vehicle group. Pathological analysis revealed that Ang II-infused Watanabe heritable hyperlipidemic rabbits that died showed myocardial infarction. Furthermore, Ang II-infused Watanabe heritable hyperlipidemic rabbits exhibited coronary plaque erosion and rupture that were associated with thrombosis. CONCLUSIONS: These findings suggest that increased blood levels of Ang II can destabilize coronary plaques and trigger the thrombosis, which possibly induces myocardial infarction. The model described in this study provides a novel means for the study of human acute coronary syndrome.


Assuntos
Angiotensina II/toxicidade , Doença da Artéria Coronariana/patologia , Vasos Coronários/efeitos dos fármacos , Hiperlipoproteinemia Tipo II/complicações , Infarto do Miocárdio/induzido quimicamente , Placa Aterosclerótica , Angiotensina II/administração & dosagem , Angiotensina II/sangue , Animais , Doença da Artéria Coronariana/genética , Vasos Coronários/patologia , Modelos Animais de Doenças , Predisposição Genética para Doença , Hereditariedade , Hiperlipoproteinemia Tipo II/genética , Bombas de Infusão Implantáveis , Infusões Subcutâneas , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Fenótipo , Coelhos , Fatores de Tempo
19.
MMWR Morb Mortal Wkly Rep ; 65(33): 844-9, 2016 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-27560948

RESUMO

In March and October 2015, the Drug Enforcement Administration (DEA) and CDC issued nationwide alerts identifying fentanyl, particularly illicitly manufactured fentanyl (IMF), as a threat to public health and safety (1,2). IMF is pharmacologically similar to pharmaceutical fentanyl (PF), but is unlawfully produced in clandestine laboratories, obtained via illicit drug markets, and includes fentanyl analogs. Fentanyl is a synthetic opioid 50-100 times more potent than morphine and approved for the management of surgical/postoperative pain, severe chronic pain, and breakthrough cancer pain.* DEA's National Forensic Laboratory Information System (NFLIS) collects drug identification results from drug cases analyzed by federal, state, and local forensic laboratories throughout the United States.(†) In 2014, 80% of fentanyl submissions (i.e., drug products obtained by law enforcement that tested positive for fentanyl) in NFLIS were identified from 10 states, including Florida and Ohio (2), and seven of these 10 states reported sharp increases in fentanyl-related overdose deaths (fentanyl deaths) (3). This report presents findings of increased fentanyl deaths during 2013-2015 from investigations conducted by the University of Florida and the Ohio Department of Public Health, in collaboration with CDC. Analyses examined the association between trends in fentanyl-related law enforcement submissions and fentanyl deaths and describes groups at risk for fentanyl death using medical examiner and coroner reports. The marked increases in fentanyl death in Florida and Ohio during 2013-2015 were closely associated with parallel increases in fentanyl submissions, with the largest impact on persons who use heroin, consistent with reports that IMF is commonly mixed with or sold as heroin (1,4). In Ohio, circumstances associated with fentanyl deaths included a current diagnosed mental health disorder(§) and recent release from an institution such as a jail, rehabilitation facility, or hospital.


Assuntos
Overdose de Drogas/mortalidade , Fentanila/intoxicação , Adolescente , Adulto , Feminino , Florida/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Ohio/epidemiologia , Adulto Jovem
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