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1.
Clin Infect Dis ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38562001

RESUMO

BACKGROUND: Evaluation of the impact on mother-to-child transmission (MTCT) of a HBV-prevention program that incorporates maternal antiviral prophylaxis is hindered by the limited availability of real-world data. METHODS: This study analyzed data on maternal HBV screening, neonatal immunization, and post-vaccination serologic testing (PVST) for HBsAg among at-risk infants born to HBV carrier mothers from the National Immunization Information System during 01/01/2008-31/12/2022. Through linkage with the National Health Insurance Database, information of maternal antiviral therapy was obtained. Multivariate logistic regression was performed to explore MTCT risk in relation to infant-mother characteristics and prevention strategies. RESULTS: Totally, 2,460,218 deliveries with maternal HBV status were screened. Between 2008 and 2022, the annual HBsAg and HBeAg seropositivity rates among native pregnant women aged 15-49 years decreased from 12.2% to 2.6% and from 2.7% to 0.4%, respectively (p for both trends < 0.0001). Among the 22,859 at-risk infants undergoing PVST, the MTCT rates differed between infants born to HBsAg-positive/HBeAg-negative and HBeAg-positive mothers (0.75% and 6.33%, respectively; p < 0.001). The MTCT rate was 1.72% (11/641) for infants born to HBeAg-positive mothers with antiviral prophylaxis. MTCT risk increased with maternal HBeAg-positivity (OR 9.29, 6.79-12.73) and decreased with maternal antiviral prophylaxis (OR 0.28, 0.16-0.49). For infants with maternal HBeAg-positivity, MTCT risk was associated with mothers born in the immunization era (OR 1.40, 1.17-1.67). CONCLUSIONS: MTCT was related to maternal HBeAg-positivity and effectively prevented by maternal prophylaxis in the immunized population. At-risk infants born to maternal vaccinated cohorts might possibly pose further risk.

2.
Emerg Infect Dis ; 30(3): 478-489, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38295401

RESUMO

Taiwan provided several COVID-19 vaccine platforms: mRNA (BNT162b2, mRNA-1273), adenoviral vector-based (AZD1222), and protein subunit (MVC-COV1901). After Taiwan shifted from its zero-COVID strategy in April 2022, population-based evaluation of vaccine effectiveness (VE) became possible. We conducted an observational cohort study of 21,416,151 persons to examine VE against SARS-CoV-2 infection, moderate and severe illness, and death during March 22, 2021-September 30, 2022. After adjusting for age and sex, we found that persons who completed 3 vaccine doses (2 primary, 1 booster) or received MVC-COV1901 as the primary series had the lowest hospitalization incidence (0.04-0.20 cases/100,000 person-days). We also found 95.8% VE against hospitalization for 3 doses of BNT162b2, 91.0% for MVC-COV1901, 81.8% for mRNA-1273, and 65.7% for AZD1222, which had the lowest overall VE. Our findings indicated that protein subunit vaccines provide similar protection against SARS-CoV-2---associated hospitalization as mRNA vaccines and can inform mix-and-match vaccine selection in other countries.


Assuntos
COVID-19 , Humanos , Vacina de mRNA-1273 contra 2019-nCoV , Vacina BNT162 , ChAdOx1 nCoV-19 , Estudos de Coortes , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , SARS-CoV-2/genética , Taiwan/epidemiologia , Eficácia de Vacinas , Masculino , Feminino
3.
Am J Epidemiol ; 193(3): 548-560, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37939113

RESUMO

In a recent systematic review, Bastos et al. (Ann Intern Med. 2021;174(4):501-510) compared the sensitivities of saliva sampling and nasopharyngeal swabs in the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by assuming a composite reference standard defined as positive if either test is positive and negative if both tests are negative (double negative). Even under a perfect specificity assumption, this approach ignores the double-negative results and risks overestimating the sensitivities due to residual misclassification. In this article, we first illustrate the impact of double-negative results in the estimation of the sensitivities in a single study, and then propose a 2-step latent class meta-analysis method for reevaluating both sensitivities using the same published data set as that used in Bastos et al. by properly including the observed double-negative results. We also conduct extensive simulation studies to compare the performance of the proposed method with Bastos et al.'s method for varied levels of prevalence and between-study heterogeneity. The results demonstrate that the sensitivities are overestimated noticeably using Bastos et al.'s method, and the proposed method provides a more accurate evaluation with nearly no bias and close-to-nominal coverage probability. In conclusion, double-negative results can significantly impact the estimated sensitivities when a gold standard is absent, and thus they should be properly incorporated.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , Resultados Negativos , Saliva , Nasofaringe
4.
Breast Cancer Res Treat ; 199(2): 381-387, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36995492

RESUMO

PURPOSE: Aspirin (ASA) use has been correlated with improved outcomes in high-risk patients at risk for distant metastases. Breast cancer (BC) patients with residual disease, particularly nodal disease (ypN +) after neoadjuvant chemotherapy (NAC), are high-risk patients portending worse outcomes. We hypothesized that ASA use can reduce distant metastases and improve outcomes in these patients. METHODS: Patients at our institutions from 2005 to 2018, with BC who did not achieve complete response (pCR) after NAC were reviewed (IRB protocol STU- 052012-019). Data, including evidence of ASA use, and clinico-pathologic parameters were analyzed. Survival outcomes were obtained (Kaplan Meier analysis) and univariate (UVA) and multivariable (MVA) Cox proportional hazards regression analyses were performed. RESULTS: 637 did not achieve pCR (ypN+ = 422). 138 were ASA users. Median follow-up for the control and ASA group were 3.8 (IQR 2.2-6.3) and 3.8 (IQR 2.5-6.4) years, respectively. Majority were stage II/III. 387 were hormone receptor positive, 191 HER2 +, and 157 triple negative. On UVA, ASA use, PR status, pathologic and clinical stage showed significance for DMFS, and disease-free survival (DFS). On MVA, ASA use associated with improved 5-year DFS (p = .01, 87.0% vs 79.6%, adjusted HR = 0.48) and improved 5-year DMFS (p = .04, 92.8% vs 89.2%, adjusted HR = 0.57). In the ypN + patients, ASA use associated with improved 5-year DMFS (p = .008, 85.7% vs 70.7%, adjusted HR = 0.43) and DFS (p = .02, 86.8% vs 74.3%, adjusted HR = 0.48). CONCLUSION: For non-responders, particularly ypN + patients, ASA use associated with improved outcome. These hypotheses-generating results suggest for development of prospective clinical trials of augmented ASA use in selected very high-risk BC patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Terapia Neoadjuvante/métodos , Estudos Prospectivos , Quimioterapia Adjuvante/métodos , Intervalo Livre de Doença , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Receptor ErbB-2 , Prognóstico
5.
J Lipid Res ; 63(11): 100288, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36162520

RESUMO

In mothers who are nursing their infants, increased clearance of plasma metabolites into the mammary gland may reduce ectopic lipid in the liver. No study to date has investigated the role of lactation on liver lipid synthesis in humans, and we hypothesized that lactation would modify fatty acid and glucose handling to support liver metabolism in a manner synchronized with the demands of milk production. Lactating (n = 18) and formula-feeding women (n = 10) underwent metabolic testing at 6-week postpartum to determine whether lactation modified intrahepatic triacylglycerols (IHTGs), measured by proton magnetic resonance spectroscopy. Subjects ingested oral deuterated water to measure fractional de novo lipogenesis (DNL) in VLDL-TG during fasting and during an isotope-labeled clamp at an insulin infusion rate of 10 mU/m2/min. Compared with formula-feeding women, we found that lactating women exhibited lower plasma VLDL-TG concentrations, similar IHTG content and similar contribution of DNL to total VLDL-TG production. These findings suggest that lactation lowers plasma VLDL-TG concentrations for reasons that are unrelated to IHTG and DNL. Surprisingly, we determined that the rate of appearance of nonesterified fatty acids was not related to IHTG in either group, and the expected positive association between DNL and IHTG was only significant in formula-feeding women. Further, in lactating women only, the higher the prolactin concentration, the lower the IHTG, while greater DNL strongly associated with elevations in VLDL-TG. In conclusion, we suggest that future studies should investigate the role of lactation and prolactin in liver lipid secretion and metabolism.


Assuntos
Lactação , Lipogênese , Feminino , Humanos , Prolactina/metabolismo , Fígado/metabolismo , Triglicerídeos/metabolismo , Período Pós-Parto
6.
Stat Med ; 41(3): 433-448, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-34859902

RESUMO

Diagnostic accuracy, a measure of diagnostic tests for correctly identifying patients with or without a target disease, plays an important role in evidence-based medicine. Diagnostic accuracy of a new test ideally should be evaluated by comparing to a gold standard; however, in many medical applications it may be invasive, costly, or even unethical to obtain a gold standard for particular diseases. When the accuracy of a new candidate test under evaluation is assessed by comparison to an imperfect reference test, bias is expected to occur and result in either overestimates or underestimates of its true accuracy. In addition, diagnostic test studies often involve repeated measurements of the same patient, such as the paired eyes or multiple teeth, and generally lead to correlated and clustered data. Using the conventional statistical methods to estimate diagnostic accuracy can be biased by ignoring the within-cluster correlations. Despite numerous statistical approaches have been proposed to tackle this problem, the methodology to deal with correlated and clustered data in the absence of a gold standard is limited. In this article, we propose a method based on the composite likelihood function to derive simple and intuitive closed-form solutions for estimates of diagnostic accuracy, in terms of sensitivity and specificity. Through simulation studies, we illustrate the relative advantages of the proposed method over the existing methods that simply treat an imperfect reference test as a gold standard in correlated and clustered data. Compared with the existing methods, the proposed method can reduce not only substantial bias, but also the computational burden. Moreover, to demonstrate the utility of this approach, we apply the proposed method to the study of National-Eye-Institute-funded Telemedicine Approaches to Evaluating of Acute-Phase Retinopathy of Prematurity (e-ROP), for estimating accuracies of both the ophthalmologist examination and the image evaluation.


Assuntos
Oftalmopatias , Recém-Nascido Prematuro , Viés , Humanos , Recém-Nascido , Funções Verossimilhança , Sensibilidade e Especificidade
7.
Am J Physiol Regul Integr Comp Physiol ; 320(3): R307-R316, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33438516

RESUMO

Excessive salt intake is considered a risk factor for the development of hypertension. Additionally, aberrant neurocirculatory responses to a cold stimulus are associated with an increased risk of hypertension. This study aimed to determine whether salt loading versus salt reduction would impact hemodynamic and sympathetic neural responses during the cold pressor test (CPT) in premenopausal women with a history of normal pregnancy. Nine healthy premenopausal women [42 ± 3 (SD) yr] were given a standardized isocaloric high-salt (HS; 250 mEq sodium/day) or low-salt (LS; 50 mEq sodium/day) diet for 1-wk each (∼2 mo apart with the order randomized), while water intake was ad libitum. Laboratory testing was performed following each HS and LS period in the mid-luteal phase of the menstrual cycle. Subjects were in the supine position and beat-by-beat blood pressure (BP), heart rate (HR), and muscle sympathetic nerve activity (MSNA) were continuously measured during 1-min baseline followed by 2-min CPT, and 3-min recovery. BP and HR increased during the CPT (both P < 0.001); the responses were similar between HS and LS. MSNA increased during the CPT, but the increment (Δ) was greater during HS than LS (29 ± 6 vs. 15 ± 4 bursts/min; P < 0.001). The transduction of MSNA for vasoconstriction during the CPT was lower in HS (P < 0.05). Thus, salt loading augments sympathetic neural reactivity to the cold stimulus with similar pressor responses compared with salt reduction, which may be attributed to the blunted neurovascular transduction-a compensatory mechanism for hemodynamic homeostasis in premenopausal women with a history of normal pregnancy.


Assuntos
Sistema Cardiovascular/inervação , Temperatura Baixa , Dieta Hipossódica , Hemodinâmica , Músculo Esquelético/inervação , Pré-Menopausa , Cloreto de Sódio na Dieta/administração & dosagem , Sistema Nervoso Simpático/fisiologia , Adulto , Pressão Sanguínea , Feminino , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade , Paridade , Gravidez , Distribuição Aleatória , Fatores de Tempo , Vasoconstrição
8.
Am J Physiol Regul Integr Comp Physiol ; 321(2): R260-R270, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34231375

RESUMO

Previous studies have demonstrated that sympathetic baroreflex sensitivity (BRS) increases during orthostatic stress in humans. We recently showed that dietary salt intake affects sympathetic neural control in healthy premenopausal women. This study aimed to determine whether salt loading versus salt reduction would impact sympathetic BRS during orthostasis in premenopausal women with a history of normal pregnancy. Nine healthy women [42 ± 3 (SD) yr] were given a standardized isocaloric high-salt (250 mEq sodium/day) or low-salt (50 mEq sodium/day) diet for 1 wk each (∼2 mo apart with the order randomized), whereas water intake was ad libitum. Laboratory testing was performed following each high- and low-salt period in the midluteal phase of the menstrual cycle. Hemodynamics and muscle sympathetic nerve activity (MSNA) were measured at baseline (supine; 2 min) and during a graded head-up tilt (30° for 5 min and 60° for 20 min). Sympathetic BRS was assessed during baseline and head-up tilt. Hemodynamics were not different between salt conditions during baseline or tilt. Both supine and upright MSNA indices were lower in high salt than low salt (all P < 0.05), however, there was no interaction effect (P = 0.507-0.996). On moving from supine to upright, sympathetic BRS remained unchanged in high salt but increased in low salt (P = 0.028 for interaction). Thus, salt loading diminishes the responsiveness of sympathetic BRS during orthostasis compared with salt reduction in healthy premenopausal women with prior normal pregnancy. Whether this is one underlying mechanism for salt-induced development of hypertension during ambulation remains to be determined.


Assuntos
Barorreflexo , Dieta Hipossódica , Tontura/fisiopatologia , Hemodinâmica , Músculo Esquelético/inervação , Cloreto de Sódio na Dieta/efeitos adversos , Sistema Nervoso Simpático/fisiopatologia , Adulto , Pressão Sanguínea , Estudos Cross-Over , Tontura/diagnóstico , Feminino , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade , Gravidez , Distribuição Aleatória , Texas , Teste da Mesa Inclinada , Fatores de Tempo
9.
Clin Auton Res ; 31(6): 767-773, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34669075

RESUMO

PURPOSE: Fluctuations in ovarian hormones during the menstrual cycle impact muscle sympathetic nerve activity burst frequency and burst incidence at rest. The purpose of this study was to investigate menstrual cycle effects on sympathetic neural burst amplitude distribution during an orthostatic challenge in young women. METHODS: This study included 11 healthy women (33 ± 10 years [mean ± standard deviation]). Muscle sympathetic nerve activity was measured in the supine position as baseline measurement and during 5 min of 60° upright tilting, during the early follicular phase (low estrogen and progesterone) and mid-luteal phase (high estrogen and progesterone) of the menstrual cycle. Relative burst amplitude distribution of muscle sympathetic nerve activity was characterized by the mean, median, skewness, and kurtosis. RESULTS: From the supine to upright position, mean and median values of relative burst amplitude increased (both P < 0.05), regardless of phases of the menstrual cycle (P = 0.5 and P = 0.7, respectively). In comparison, during the early follicular phase, skewness and kurtosis remained unchanged (P = 0.6 and P = 0.3, respectively) and kurtosis decreased (1.25 ± 1.11 supine vs. - 0.03 ± 0.73 upright; P = 0.02); there was no change in skewness during the mid-luteal phase (P = 0.4). CONCLUSIONS: In response to orthostasis, while the symmetry and tailedness/peakness of burst amplitude distribution do not change during the early follicular phase, the distribution during the mid-luteal phase becomes flatter with a lower but broader peak. The latter result suggests that the firing probability of large axon action potentials in response to orthostatic challenge is higher when estrogen and progesterone levels are elevated. The role of changes in sympathetic neural burst amplitude distribution in orthostatic tolerance remains to be determined.


Assuntos
Tontura , Ciclo Menstrual , Feminino , Humanos , Fase Luteal , Progesterona , Sistema Nervoso Simpático
10.
Emerg Infect Dis ; 26(7): 1567-1570, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32197059

RESUMO

Early infections with severe acute respiratory syndrome coronavirus 2 in Europe were detected in travelers from Wuhan, China, in January 2020. In 1 tour group, 5 of 30 members were ill; 3 cases were laboratory confirmed. In addition, a healthcare worker was infected. This event documents early importation and subsequent spread of the virus in Europe.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , COVID-19 , Infecções por Coronavirus/transmissão , Europa (Continente)/epidemiologia , Humanos , Pandemias , Pneumonia Viral/transmissão , SARS-CoV-2 , Viagem
11.
J Med Internet Res ; 22(8): e15394, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32755888

RESUMO

BACKGROUND: Changeful seasonal influenza activity in subtropical areas such as Taiwan causes problems in epidemic preparedness. The Taiwan Centers for Disease Control has maintained real-time national influenza surveillance systems since 2004. Except for timely monitoring, epidemic forecasting using the national influenza surveillance data can provide pivotal information for public health response. OBJECTIVE: We aimed to develop predictive models using machine learning to provide real-time influenza-like illness forecasts. METHODS: Using surveillance data of influenza-like illness visits from emergency departments (from the Real-Time Outbreak and Disease Surveillance System), outpatient departments (from the National Health Insurance database), and the records of patients with severe influenza with complications (from the National Notifiable Disease Surveillance System), we developed 4 machine learning models (autoregressive integrated moving average, random forest, support vector regression, and extreme gradient boosting) to produce weekly influenza-like illness predictions for a given week and 3 subsequent weeks. We established a framework of the machine learning models and used an ensemble approach called stacking to integrate these predictions. We trained the models using historical data from 2008-2014. We evaluated their predictive ability during 2015-2017 for each of the 4-week time periods using Pearson correlation, mean absolute percentage error (MAPE), and hit rate of trend prediction. A dashboard website was built to visualize the forecasts, and the results of real-world implementation of this forecasting framework in 2018 were evaluated using the same metrics. RESULTS: All models could accurately predict the timing and magnitudes of the seasonal peaks in the then-current week (nowcast) (ρ=0.802-0.965; MAPE: 5.2%-9.2%; hit rate: 0.577-0.756), 1-week (ρ=0.803-0.918; MAPE: 8.3%-11.8%; hit rate: 0.643-0.747), 2-week (ρ=0.783-0.867; MAPE: 10.1%-15.3%; hit rate: 0.669-0.734), and 3-week forecasts (ρ=0.676-0.801; MAPE: 12.0%-18.9%; hit rate: 0.643-0.786), especially the ensemble model. In real-world implementation in 2018, the forecasting performance was still accurate in nowcasts (ρ=0.875-0.969; MAPE: 5.3%-8.0%; hit rate: 0.582-0.782) and remained satisfactory in 3-week forecasts (ρ=0.721-0.908; MAPE: 7.6%-13.5%; hit rate: 0.596-0.904). CONCLUSIONS: This machine learning and ensemble approach can make accurate, real-time influenza-like illness forecasts for a 4-week period, and thus, facilitate decision making.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Influenza Humana/epidemiologia , Aprendizado de Máquina/normas , Previsões , Humanos , Taiwan
12.
Proc Natl Acad Sci U S A ; 112(42): 13069-74, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26438851

RESUMO

Dengue is a mosquito-transmitted virus infection that causes epidemics of febrile illness and hemorrhagic fever across the tropics and subtropics worldwide. Annual epidemics are commonly observed, but there is substantial spatiotemporal heterogeneity in intensity. A better understanding of this heterogeneity in dengue transmission could lead to improved epidemic prediction and disease control. Time series decomposition methods enable the isolation and study of temporal epidemic dynamics with a specific periodicity (e.g., annual cycles related to climatic drivers and multiannual cycles caused by dynamics in population immunity). We collected and analyzed up to 18 y of monthly dengue surveillance reports on a total of 3.5 million reported dengue cases from 273 provinces in eight countries in Southeast Asia, covering ∼ 10(7) km(2). We detected strong patterns of synchronous dengue transmission across the entire region, most markedly during a period of high incidence in 1997-1998, which was followed by a period of extremely low incidence in 2001-2002. This synchrony in dengue incidence coincided with elevated temperatures throughout the region in 1997-1998 and the strongest El Niño episode of the century. Multiannual dengue cycles (2-5 y) were highly coherent with the Oceanic Niño Index, and synchrony of these cycles increased with temperature. We also detected localized traveling waves of multiannual dengue epidemic cycles in Thailand, Laos, and the Philippines that were dependent on temperature. This study reveals forcing mechanisms that drive synchronization of dengue epidemics on a continental scale across Southeast Asia.


Assuntos
Dengue/epidemiologia , Sudeste Asiático/epidemiologia , Clima , Dengue/transmissão , Surtos de Doenças , Humanos , Incidência
13.
J Clin Microbiol ; 54(6): 1528-1535, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27030492

RESUMO

Dengue virus (DENV) infection is considered a major public health problem in developing tropical countries where the virus is endemic and continues to cause major disease outbreaks every year. Here, we describe the development of a novel, inexpensive, and user-friendly diagnostic assay based on a reverse transcription-insulated isothermal PCR (RT-iiPCR) method for the detection of all four serotypes of DENV in clinical samples. The diagnostic performance of the newly established pan-DENV RT-iiPCR assay targeting a conserved 3' untranslated region of the viral genome was evaluated. The limit of detection with a 95% confidence was estimated to be 10 copies of in vitro-transcribed (IVT) RNA. Sensitivity analysis using RNA prepared from 10-fold serial dilutions of tissue culture fluid containing DENVs suggested that the RT-iiPCR assay was comparable to the multiplex real-time quantitative RT-PCR (qRT-PCR) assay for DENV-1, -3, and -4 detection but 10-fold less sensitive for DENV-2 detection. Subsequently, plasma collected from patients suspected of dengue virus infection (n = 220) and individuals not suspected of dengue virus infection (n = 45) were tested by the RT-iiPCR and compared to original test results using a DENV NS1 antigen rapid test and the qRT-PCR. The diagnostic agreement of the pan-DENV RT-iiPCR, NS1 antigen rapid test, and qRT-PCR tests was 93.9%, 84.5%, and 97.4%, respectively, compared to the composite reference results. This new RT-iiPCR assay along with the portable POCKIT nucleic acid analyzer could provide a highly reliable, sensitive, and specific point-of-need diagnostic assay for the diagnosis of DENV in clinics and hospitals in developing countries.


Assuntos
Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Vírus da Dengue/genética , Humanos , Sensibilidade e Especificidade
14.
Anal Chem ; 86(15): 7192-9, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25019532

RESUMO

We demonstrate an inspection technique, based on only one ellipsometric parameter, Ψ, of spectroscopic ellipsometry (SE), for the rapid, simultaneous identification of both the structural quality and thicknesses of large-area graphene films. The measured Ψ spectra are strongly affected by changes in the out-of-plane absorption coefficients (αTM); they are also correlated to the ratio of the intensities of the D and G bands in Raman spectra of graphene films. In addition, the electronic transition state of graphene within the UV regime assists the characterization of the structural quality. We also demonstrated that the intensities and shifts of the signals in Ψ spectra allow clear identification of the structural qualities and thicknesses, respectively, of graphene films. Moreover, this Ψ-based method can be further applied to graphene films coated on various substrates. In addition, mapping of the values of Ψ is a very convenient and useful means of rapidly characterizing both the structural quality and thickness of 2D materials at local areas. Therefore, this Ψ-based characterization method has great potential for application in the mass production of devices based on large-area graphene.

15.
Foodborne Pathog Dis ; 11(3): 230-3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24313786

RESUMO

Food sold over the internet is an emerging business that also presents a concern with regard to food safety. A nationwide foodborne disease outbreak associated with sandwiches purchased from an online shop in July 2010 is reported. Consumers were telephone interviewed with a structured questionnaire and specimens were collected for etiological examination. A total of 886 consumers were successfully contacted and completed the questionnaires; 36.6% had become ill, with a median incubation period of 18 h (range, 6-66 h). The major symptoms included diarrhea (89.2%), abdominal pain (69.8%), fever (47.5%), headache (32.7%), and vomiting (17.3%). Microbiological laboratories isolated Salmonella enterica serovar Enteritidis, Salmonella Virchow, Staphylococcus aureus, Bacillus cereus, and enterotoxigenic Escherichia coli from the contaminated sandwiches, Salmonella Enteritidis and Salmonella Virchow from the patients, and Salmonella Enteritidis and Staphylococcus aureus from food handlers. Pulsed-field gel electrophoresis genotyping suggested a common origin of Salmonella bacteria recovered from the patients, food, and a food handler. Among the pathogens detected, the symptoms and incubation period indicated that Salmonella, likely of egg origin, was the probable causative agent of the outbreak. This outbreak illustrates the importance of meticulous hygiene practices during food preparation and temperature control during food shipment and the food safety challenges posed by online food-shopping services.


Assuntos
Surtos de Doenças , Ovos/microbiologia , Microbiologia de Alimentos , Serviços de Alimentação , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacillus cereus/genética , Bacillus cereus/isolamento & purificação , Criança , Pré-Escolar , Escherichia coli Enterotoxigênica/genética , Escherichia coli Enterotoxigênica/isolamento & purificação , Feminino , Serviços de Alimentação/normas , Serviços de Alimentação/tendências , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Genótipo , Humanos , Lactente , Internet , Masculino , Pessoa de Meia-Idade , Salmonella/genética , Intoxicação Alimentar por Salmonella/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Taiwan/epidemiologia , Adulto Jovem
16.
medRxiv ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38947001

RESUMO

Network meta-analysis, also known as mixed treatments comparison meta-analysis or multiple treatments meta-analysis, extends conventional pairwise meta-analysis by simultaneously synthesizing multiple interventions in a single integrated analysis. Despite the growing popularity of network meta-analysis within comparative effectiveness research, it comes with potential challenges. For example, within-study correlations among treatment comparisons are rarely reported in the published literature. Yet, these correlations are pivotal for valid statistical inference. As demonstrated in earlier studies, ignoring these correlations can inflate mean squared errors of the resulting point estimates and lead to inaccurate standard error estimates. This paper introduces a composite likelihood-based approach that ensures accurate statistical inference without requiring knowledge of the within-study correlations. The proposed method is computationally robust and efficient, with substantially reduced computational time compared to the state-of-the-science methods implemented in R packages. The proposed method was evaluated through extensive simulations and applied to two important applications including a network meta-analysis comparing interventions for primary open-angle glaucoma, and another comparing treatments for chronic prostatitis and chronic pelvic pain syndrome. Highlights: What is already known?: Network meta-analysis extends conventional pairwise meta-analysis by simultaneously synthesizing multiple interventions in a single integrated analysis.A significant challenge in network meta-analysis is the lack of reported within-study correlations among treatment comparisons in the published studies.What is new?: We propose a new method for network meta-analysis that ensures vaild statistical inference without the need for knowledge of within-study correlations.The proposed method employs a composite likelihood and a sandwich-type robust variance estimator, offering a computationally efficient and scalable solution, particularly for network meta-analysis with a large number of treatments and studies.Potential impact for Research Synthesis Methods readers: The proposed method can be easily applied to any univariate network meta-analysis project without requiring knowledge of within-study correlations among treatment comparisons.

17.
Anal Chem ; 85(3): 1605-14, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23323974

RESUMO

In this study, we find that the optical anisotropy of graphene films could be used as an alternative quality factor for the rapid characterization of large-area graphene films prepared through chemical vapor deposition. We develop an angle-variable spectroscopic method to rapidly determine the optical anisotropy of graphene films. Unlike approaches using Raman scattering spectroscopy, this optical anisotropy method allows ready characterization of the structural quality of large-area graphene samples without the application of high-intensity laser irradiation or complicated optical setups. Measurements of optical anisotropy also allow us to distinguish graphene samples with different extents of structural imperfections; the results are consistent with those obtained from using Raman scattering spectroscopy. In addition, we also study the properties of graphene-based transparent conductive films at wide incident angles because of the advantage of the optical anisotropic properties of graphene. The transmittance of graphene is much higher than that of indium tin oxide films, especially at large incident angles.

18.
Respir Physiol Neurobiol ; 318: 104151, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37673304

RESUMO

We investigated whether older adults (OA) with obesity are more likely to have dyspnea compared with OA without obesity, and whether OA with obesity are at a greater risk of having dyspnea compared with middle-aged (MA) and younger adults (YA) with obesity. We obtained de-identified data from the TriNetX UT Southwestern Medical Center database. We identified obesity and dyspnea using ICD-10-CM codes E66 and R06.0, respectively. Patients were separated into three age groups: OA, (65-75 y.o.), MA (45-55 y.o.), and YA (25-35 y.o). Within these groups, those with and without obesity or dyspnea were identified for analysis. The risk of dyspnea was greater in OA (risk ratio: 3.64), MA (risk ratio: 3.52), and YA (risk ratio: 2.76) with obesity compared with age-matched patients without obesity (all p < 0.01). The risk of dyspnea was greater in OA and MA with obesity compared with YA with obesity (both p < 0.001 vs. YA). These findings suggest that clinicians should consider obesity as an independent risk factor for dyspnea.

19.
J Pediatr Endocrinol Metab ; 36(11): 1012-1017, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37795854

RESUMO

OBJECTIVES: Impaired linear growth is a known complication of pediatric inflammatory bowel disease (IBD), but the use of growth hormone (GH) in this population is not well-described. The primary aim of this study is to determine whether growth hormone use in pediatric IBD leads to improved height outcomes. METHODS: This was a retrospective chart review of patients with IBD aged 0-21 years followed at a single center between 2018 and 2021 treated with at least 1 year of GH. Records collected included demographics, IBD phenotype, IBD disease activity scores, medications, weight z-score, height z-score, bone age, and details of GH therapy including testing for GH deficiency. The primary outcome measure was change in height z-score after 1 year of GH treatment. RESULTS: Forty-six patients were identified and 18 were excluded. Of the 28 patients included (7 female; 25.0 %), 26 (92.9 %) had a diagnosis of Crohn's disease (CD) and 2 (7.1 %) had ulcerative colitis (UC). The mean (SD) age at GH initiation was 9.6 (3.4) years. Among all participants, there was a significant mean difference in height z-score from baseline to 1 year on therapy (-2.25 vs. -1.50, respectively; difference, 0.75; 95 % CI, 0.56 to 0.94; p<0.001). Among the 19 subjects that completed GH therapy there was a significant mean difference between baseline and final height z-scores (-2.41 vs. -0.77, respectively; difference, 1.64; 95 % CI, 1.30 to 1.98; p<0.001). CONCLUSIONS: GH use was associated with improved height outcomes. The pediatric IBD patients in this cohort had significant improvements in height z-scores both after one year on therapy and at completion of GH therapy.


Assuntos
Doença de Crohn , Hormônio do Crescimento Humano , Doenças Inflamatórias Intestinais , Humanos , Criança , Feminino , Hormônio do Crescimento/uso terapêutico , Estudos Retrospectivos , Hormônio do Crescimento Humano/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doença de Crohn/tratamento farmacológico
20.
J Breast Cancer ; 26(1): 14-24, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36762783

RESUMO

PURPOSE: Inflammatory breast cancer (IBC) is the most aggressive form of breast cancer and has a high propensity for distant metastases. Our previous data suggested that aspirin (acetylsalicylic acid, ASA) use may be associated with reduced risk of distant metastases in aggressive breast cancer; however, there are no reported studies on the potential benefit of ASA use in patients with IBC. METHODS: Data from patients with non-metastatic IBC treated between 2000-2017 at two institutions, were reviewed. Overall survival (OS), disease-free survival (DFS), and distant metastasis-free survival (DMFS) were performed using Kaplan-Meier analysis. Univariate and multivariable logistic regression models were used to identify significant associated factors. RESULTS: Of 59 patients meeting the criteria for analysis and available for review, 14 ASA users were identified. ASA users demonstrated increased OS (p = 0.03) and DMFS (p = 0.02), with 5-year OS and DMFS of 92% (p = 0.01) and 85% (p = 0.01) compared to 51% and 43%, respectively, for non-ASA users. In univariate analysis, pT stage, pN stage, and ASA use were significantly correlated (p < 0.05) with OS and DFS. On multivariable analysis, ASA use (hazard ratio [HR], 0.11; 95% confidence interval [CI], 0.01-0.8) and lymph node stage (HR, 5.9; 95% CI, 1.4-25.9) remained significant for OS and DFS ASA use (HR, 0.13; 95% CI, 0.03-0.56) and lymph node stage (HR, 5.6; 95% CI, 1.9-16.4). CONCLUSION: ASA use during remission was associated with significantly improved OS and DMFS in patients with IBC. These results suggest that ASA may provide survival benefits to patients with IBC. Prospective clinical trials of ASA use in patients with high-risk IBC in remission should be considered.

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