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1.
Clin Infect Dis ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38562001

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38295401

RESUMEN

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.


Asunto(s)
COVID-19 , Humanos , Vacuna nCoV-2019 mRNA-1273 , Vacuna BNT162 , ChAdOx1 nCoV-19 , Estudios de Cohortes , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , SARS-CoV-2/genética , Taiwán/epidemiología , Eficacia de las Vacunas , Masculino , Femenino
3.
Am J Epidemiol ; 193(3): 548-560, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-37939113

RESUMEN

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.


Asunto(s)
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , Resultados Negativos , Saliva , Nasofaringe
4.
J Pediatr Endocrinol Metab ; 36(11): 1012-1017, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37795854

RESUMEN

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.


Asunto(s)
Enfermedad de Crohn , Hormona de Crecimiento Humana , Enfermedades Inflamatorias del Intestino , Humanos , Niño , Femenino , Hormona del Crecimiento/uso terapéutico , Estudios Retrospectivos , Hormona de Crecimiento Humana/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico
5.
Respir Physiol Neurobiol ; 318: 104151, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37673304

RESUMEN

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.

6.
Kidney Med ; 5(6): 100634, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37235044

RESUMEN

Rationale and Objective: Serum magnesium levels have been inversely yet inconsistently associated with cardiovascular (CV) outcomes. In this study, we examined the association of serum magnesium levels with CV outcomes in the Systolic Blood Pressure Intervention Trial (SPRINT) participants. Study Design: Case-control post hoc analysis of SPRINT. Setting & Participants: A total of 2,040 SPRINT participants with available serum samples at baseline level were included in this study. Case participants (n = 510) who experienced a CV event during the SPRINT observation period (median follow-up of 3.2 years) and control participants (n = 1,530) without CV events were sampled in a 1:3 ratio for measurements of serum magnesium level at baseline and 2-year follow-up. Predictors: Baseline serum magnesium levels and 2-year percentage change in serum magnesium levels (ΔSMg). Outcome: SPRINT primary composite CV outcome. Analytical Approach: Multivariable conditional logistic regression analysis, accounting for matching factors, was used to evaluate the association of baseline and ΔSMg with CV outcomes. Individual matching of cases and controls was based on the SPRINT treatment arm allocation (standard vs intensive) and prevalence of chronic kidney disease (CKD). Results: The median serum magnesium level at baseline was similar among the case and control groups. In a fully adjusted model, each standard deviation (SD) (0.18 mg/dL) higher of the baseline serum magnesium level was independently associated with a lower risk for composite CV outcomes in all study participants (adjusted odds ratio 95% CI, 0.79 [0.70-0.89]). This association was similar when serum magnesium levels were analyzed in quartiles but dissipated in the standard (vs intensive) arm of SPRINT (0.88 [0.76-1.02] vs 0.65 [0.53-0.79], respectively; Pinteraction = 0.06). The presence or absence of CKD at baseline did not modify this association. ΔSMg was not independently associated with CV outcomes occurring after 2 years. Limitations: ΔSMg was small in magnitude, limiting effect size. Conclusions: Higher baseline serum magnesium levels were independently associated with reduced risk for CV outcomes in all study participants, but ΔSMg was not associated with CV outcomes.

7.
Breast Cancer Res Treat ; 199(2): 381-387, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36995492

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Terapia Neoadyuvante/métodos , Estudios Prospectivos , Quimioterapia Adyuvante/métodos , Supervivencia sin Enfermedad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Receptor ErbB-2 , Pronóstico
8.
Nanoscale ; 15(14): 6581-6587, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36939817

RESUMEN

In this work, we aim to fabricate a highly stable and flexible perovskite paper photodetector based on a Zn-doped MA0.6FA0.4PbI3 perovskite and CNC. The paper photodetector has been successfully synthesized by the vacuum filtration method and deposited with interdigitated electrodes. The paper photodetector exhibits a significant photoresponse with a responsivity of 0.23 A W-1 under 650 nm light irradiation when operated at 5 V. The stability of the paper photodetector has also been tested and it shows high photoresponse after 30 days under ambient conditions. Therefore, this paper photodetector holds promise for developing efficient, stable, and flexible optoelectronic devices in the future.

9.
J Microbiol Immunol Infect ; 56(3): 558-565, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36804307

RESUMEN

BACKGROUND: An extended interval between the two primary doses may reduce the risk of myocarditis/pericarditis after COVID-19 mRNA vaccination. Taiwan has implemented a two-dose regimen with a 12-week interval for adolescents. Here we present nationwide data of myocarditis/pericarditis following COVID-19 vaccinations. METHODS: Data on adverse events of myocarditis/pericarditis were from the Taiwan Vaccine Adverse Events Reporting System between March 22, 2021, and February 9, 2022. The reporting rates according to sex, age, and vaccine type were calculated. We investigated the rates among young individuals under different two-dose intervals and among those who received two doses of different vaccines. RESULTS: Among 204 cases who met the case definition of myocarditis/pericarditis, 75 cases occurred after the first dose and 129 after the second. The rate of myocarditis/pericarditis after COVID-19 vaccination varied across sex and age groups and was highest after the second dose in males aged 12-17 years (126.79 cases per million vaccinees) for the BNT162b2 vaccine and in males aged 18-24 years (93.84 cases per million vaccinees) for the mRNA-1273 vaccine. The data did not suggest an association between longer between-dose interval and lower rate of myocarditis/pericarditis among males and females aged 18-24 or 25-29 years who received two doses of the BNT162b2 or mRNA-1273 vaccine. Rates of myocarditis/pericarditis in males and females aged 18-49 years after receiving ChAdOx1-S - mRNA-1273 vaccination was significantly higher than after ChAdOx1-S - ChAdOx1-S vaccination. CONCLUSIONS: Myocarditis and pericarditis are rare following mRNA vaccination, with higher risk occurring in young males after the second dose.


Asunto(s)
COVID-19 , Miocarditis , Pericarditis , Adolescente , Femenino , Humanos , Masculino , Vacuna nCoV-2019 mRNA-1273 , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Miocarditis/epidemiología , Miocarditis/etiología , Pericarditis/epidemiología , Pericarditis/etiología , ARN Mensajero , Vacunación/efectos adversos , Adulto Joven , Adulto
10.
J Breast Cancer ; 26(1): 14-24, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36762783

RESUMEN

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.

11.
J Lipid Res ; 63(11): 100288, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36162520

RESUMEN

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.


Asunto(s)
Lactancia , Lipogénesis , Femenino , Humanos , Prolactina/metabolismo , Hígado/metabolismo , Triglicéridos/metabolismo , Periodo Posparto
12.
IEEE Trans Pattern Anal Mach Intell ; 44(11): 8387-8402, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34506277

RESUMEN

We present a learning-based approach for removing unwanted obstructions, such as window reflections, fence occlusions, or adherent raindrops, from a short sequence of images captured by a moving camera. Our method leverages motion differences between the background and obstructing elements to recover both layers. Specifically, we alternate between estimating dense optical flow fields of the two layers and reconstructing each layer from the flow-warped images via a deep convolutional neural network. This learning-based layer reconstruction module facilitates accommodating potential errors in the flow estimation and brittle assumptions, such as brightness consistency. We show that the proposed approach learned from synthetically generated data performs well to real images. Experimental results on numerous challenging scenarios of reflection and fence removal demonstrate the effectiveness of the proposed method.

13.
Stat Med ; 41(3): 433-448, 2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-34859902

RESUMEN

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.


Asunto(s)
Oftalmopatías , Recien Nacido Prematuro , Sesgo , Humanos , Recién Nacido , Funciones de Verosimilitud , Sensibilidad y Especificidad
14.
Materials (Basel) ; 16(1)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36614436

RESUMEN

GaN nanowires (NWs) grown on silicon via atmospheric pressure chemical vapor deposition were doped with Cobalt (Co) by ion implantation, with a high dose concentration of 4 × 1016 cm-2, corresponding to an average atomic percentage of ~3.85%, and annealed after the implantation. Co-doped GaN showed optimum structural properties when annealed at 700 °C for 6 min in NH3 ambience. From scanning electron microscopy, X-ray diffraction, high resolution transmission electron microscope, and energy dispersive X-ray spectroscopy measurements and analyses, the single crystalline nature of Co-GaN NWs was identified. Slight expansion in the lattice constant of Co-GaN NWs due to the implantation-induced stress effect was observed, which was recovered by thermal annealing. Co-GaN NWs exhibited ferromagnetism as per the superconducting quantum interference device (SQUID) measurement. Hysteretic curves with Hc (coercivity) of 502.5 Oe at 5 K and 201.3 Oe at 300 K were obtained. Applied with a magnetic field of 100 Oe, the transition point between paramagnetic property and ferromagnetic property was determined at 332 K. Interesting structural and conducive magnetic properties show the potential of Co-doped GaN nanowires for the next optoelectronic, electronic, spintronic, sensing, optical, and related applications.

15.
Clin Auton Res ; 31(6): 767-773, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34669075

RESUMEN

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.


Asunto(s)
Mareo , Ciclo Menstrual , Femenino , Humanos , Fase Luteínica , Progesterona , Sistema Nervioso Simpático
16.
Am J Physiol Regul Integr Comp Physiol ; 321(2): R260-R270, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34231375

RESUMEN

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.


Asunto(s)
Barorreflejo , Dieta Hiposódica , Mareo/fisiopatología , Hemodinámica , Músculo Esquelético/inervación , Cloruro de Sodio Dietético/efectos adversos , Sistema Nervioso Simpático/fisiopatología , Adulto , Presión Sanguínea , Estudios Cruzados , Mareo/diagnóstico , Femenino , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad , Embarazo , Distribución Aleatoria , Texas , Pruebas de Mesa Inclinada , Factores de Tiempo
17.
Am J Physiol Regul Integr Comp Physiol ; 320(3): R307-R316, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33438516

RESUMEN

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.


Asunto(s)
Sistema Cardiovascular/inervación , Frío , Dieta Hiposódica , Hemodinámica , Músculo Esquelético/inervación , Premenopausia , Cloruro de Sodio Dietético/administración & dosificación , Sistema Nervioso Simpático/fisiología , Adulto , Presión Sanguínea , Femenino , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad , Paridad , Embarazo , Distribución Aleatoria , Factores de Tiempo , Vasoconstricción
18.
Kidney360 ; 2(10): 1553-1559, 2021 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-35372968

RESUMEN

Background: Various causes of hypokalemia (HK) from renal potassium wasting, including distal renal tubular acidosis (RTA), have been described in lupus nephritis (LN). We report a phenomenon of otherwise unexplained HK among a population with LN. Methods: From our population of 403 patients with LN, we identified a cohort of 20 patients with idiopathic HK, defined by serum potassium <3.5 mmol/L without any apparent explanation. This cohort is compared with 90 LN controls (CON) and ten patients with LN with distal RTA from the same population. Results: The patients with HK had lower median serum potassium compared with CON and RTA subjects (3.26 versus 4.00 versus 3.75 mmol/L, respectively; P<0.001). The median serum bicarbonate was normal in HK and CON, but low in RTA (26.0 versus 25.0 versus 19.4 mmol/L; P<0.001). The median urine pH was abnormally high only in the RTA group (6.00 versus 6.25 versus 6.67; P=0.012). The median serum magnesium was modestly lower in HK compared with the CON and RTA groups (1.73 versus 2.00 versus 1.85 mg/dl; P=0.002). Although both HK and RTA showed a higher rate of seropositivity than CON for anti-Ro/SSA (79% and 80% versus 37%, respectively; P<0.001), only HK revealed a higher rate of seropositivity than CON for anti-RNP (84% versus 42%; P=0.003) and only RTA showed a higher rate of seropositivity than CON for anti-La/SSB (40% versus 12%; P=0.05). Conclusions: A syndrome of idiopathic HK was revealed in 20 out of 403 (5%) of patients within our LN population, and proved to be distinct from the RTA that occurs in LN. Furthermore, it was associated with a distinct pattern of autoantibodies. We speculate that idiopathic HK is the result of a novel target of autoimmunity in LN, affecting renal tubular potassium transport.


Asunto(s)
Acidosis Tubular Renal , Hipopotasemia , Nefritis Lúpica , Acidosis Tubular Renal/complicaciones , Bicarbonatos , Humanos , Hipopotasemia/etiología , Nefritis Lúpica/complicaciones , Potasio
19.
J Med Internet Res ; 22(8): e15394, 2020 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-32755888

RESUMEN

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.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Gripe Humana/epidemiología , Aprendizaje Automático/normas , Predicción , Humanos , Taiwán
20.
Emerg Infect Dis ; 26(7): 1567-1570, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32197059

RESUMEN

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.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , COVID-19 , Infecciones por Coronavirus/transmisión , Europa (Continente)/epidemiología , Humanos , Pandemias , Neumonía Viral/transmisión , SARS-CoV-2 , Viaje
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