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1.
Nature ; 602(7895): 63-67, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35110756

RESUMEN

Electrically charged particles can be created by the decay of strong enough electric fields, a phenomenon known as the Schwinger mechanism1. By electromagnetic duality, a sufficiently strong magnetic field would similarly produce magnetic monopoles, if they exist2. Magnetic monopoles are hypothetical fundamental particles that are predicted by several theories beyond the standard model3-7 but have never been experimentally detected. Searching for the existence of magnetic monopoles via the Schwinger mechanism has not yet been attempted, but it is advantageous, owing to the possibility of calculating its rate through semi-classical techniques without perturbation theory, as well as that the production of the magnetic monopoles should be enhanced by their finite size8,9 and strong coupling to photons2,10. Here we present a search for magnetic monopole production by the Schwinger mechanism in Pb-Pb heavy ion collisions at the Large Hadron Collider, producing the strongest known magnetic fields in the current Universe11. It was conducted by the MoEDAL experiment, whose trapping detectors were exposed to 0.235 per nanobarn, or approximately 1.8 × 109, of Pb-Pb collisions with 5.02-teraelectronvolt center-of-mass energy per collision in November 2018. A superconducting quantum interference device (SQUID) magnetometer scanned the trapping detectors of MoEDAL for the presence of magnetic charge, which would induce a persistent current in the SQUID. Magnetic monopoles with integer Dirac charges of 1, 2 and 3 and masses up to 75 gigaelectronvolts per speed of light squared were excluded by the analysis at the 95% confidence level. This provides a lower mass limit for finite-size magnetic monopoles from a collider search and greatly extends previous mass bounds.

2.
Proc Natl Acad Sci U S A ; 119(49): e2203071119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36442132

RESUMEN

Remodeling of the uterine vasculature by invasive extravillous trophoblasts (EVTs) is a critical aspect of human placentation. Insufficient EVT invasion can lead to severe obstetrical complications like preeclampsia, intrauterine growth restriction, and preterm birth. Glial cells missing-1 (GCM1) is a transcription factor that is crucial for proper placentation in mice, and is highly expressed in human syncytiotrophoblast (ST) and EVTs. GCM1 is classically considered a master regulator of ST formation, but little is known about its contribution to the development and function of EVTs. Therefore, in this study we test the hypothesis that GCM1 is a critical regulator of both EVT and ST development and function. We show that GCM1 is highly expressed in human trophoblast stem (TS) cells differentiated into either ST or EVTs. Knockdown of GCM1 in TS cells hindered differentiation into both ST and EVT pathways. When placed in ST media, GCM1-knockdown cells formed small, unstable clusters; when placed in EVT media, cells had altered morphology and transcript profiles resembling cells trapped in an intermediate state between CT and EVT, and invasive capacity through matrix was reduced. RNA sequencing analysis of GCM1-deficient TS cells revealed downregulation of EVT-associated genes and enrichment in transcripts related to WNT signaling, which was linked to decreased expression of the EVT master regulator ASCL2 and the WNT antagonist NOTUM. Our findings reveal an essential role of GCM1 during ST and EVT development, and suggest that GCM1 regulates differentiation of human TS cells into EVTs by inducing expression of ASCL2 and NOTUM.


Asunto(s)
Nacimiento Prematuro , Trofoblastos , Recién Nacido , Femenino , Embarazo , Humanos , Animales , Ratones , Neuroglía , Diferenciación Celular , Células Madre , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Proteínas de Unión al ADN/genética , Factores de Transcripción/genética
3.
Skeletal Radiol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38653786

RESUMEN

OBJECTIVE: To prospectively evaluate a deep learning-based denoising reconstruction (DLR) for improved resolution and image quality in musculoskeletal (MSK) magnetic resonance imaging (MRI). METHODS: Images from 137 contrast-weighted sequences in 40 MSK patients were evaluated. Each sequence was performed twice, first with the routine parameters and reconstructed with a routine reconstruction filter (REF), then with higher resolution and reconstructed with DLR, and with three conventional reconstruction filters (NL2, GA43, GA53). The five reconstructions (REF, DLR, NL2, GA43, and GA53) were de-identified, randomized, and blindly reviewed by three MSK radiologists using eight scoring criteria and a forced ranking. Quantitative SNR, CNR, and structure's full width at half maximum (FWHM) for resolution assessment were measured and compared. To account for repeated measures, Generalized Estimating Equations (GEE) with Bonferroni adjustment was used to compare the reader's scores, SNR, CNR, and FWHM between DLR vs. NL2, GA43, GA53, and REF. RESULTS: Compared to the routine REF images, the resolution was improved by 47.61% with DLR from 0.39 ± 0.15 mm2 to 0.20 ± 0.06 mm2 (p < 0.001). Per-sequence average scan time was shortened by 7.93% with DLR from 165.58 ± 21.86 s to 152.45 ± 25.65 s (p < 0.001). Based on the average scores, DLR images were rated significantly higher in all image quality criteria and the forced ranking (p < 0.001). CONCLUSION: This prospective clinical evaluation demonstrated that DLR allows approximately two times finer resolution and improved image quality compared to the standard-of-care images.

4.
Ann Ig ; 35(5): 586-601, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36960886

RESUMEN

Objectives: To standardize a questionnaire about drug dispensers' attitudes and behaviors in dispensing antibiotics without prescription, and to evaluate drug dispensers' attitudes, behaviors, and relevant factors in dispensing antibiotics without prescription at community pharmacies in Can Tho City, Vietnam. Methods: A descriptive cross-sectional study was conducted among community pharmacists in Can Tho City, Vietnam from June to December 2022. A self-administered questionnaire designed according to the Theory of Planned Behavior was used for data collection. The questionnaire was composed of 33 statements scored on the 5-point Likert scale, which was completed by interviews with 180 pharmacy dispensers to Can Tho. Exploratory Factor Analysis was also utilized to uncover major determinants of dispensing antibiotics without prescription. Results: Of the 180 participants, 65% of drug dispensers were female (n=117), 59.4% were university graduates (n= 107), and 80.6% had experience of less than 10 years (n=145). A pharmacy is the first destination people think about when they have a health issue. Unfortunately, dispensing antibiotics without a valid prescription is not in compliance with governmental regulations. In the study, perceived behavioral control factors were found to be the most critical determinants of the behavior, followed by subjective norms. By contrast, attitudinal factors presented no impact on intention to dispensing antibiotics without prescription. Conclusions: The provision of non-prescription is primarily influenced by the perception of the distributors and external factors. Developing interventions is necessary to increase public awareness of the misuse and misunderstanding of antibiotics.


Asunto(s)
Servicios Comunitarios de Farmacia , Farmacias , Humanos , Femenino , Masculino , Estudios Transversales , Antibacterianos , Vietnam , Actitud
5.
N Engl J Med ; 381(11): 1001-1010, 2019 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-31340089

RESUMEN

BACKGROUND: Roxadustat (FG-4592) is an oral inhibitor of hypoxia-inducible factor (HIF) prolyl hydroxylase that stimulates erythropoiesis and regulates iron metabolism. In phase 2 studies involving patients with chronic kidney disease, roxadustat increased levels of endogenous erythropoietin to within or near the physiologic range, along with increasing hemoglobin levels and improving iron homeostasis. Additional data are needed regarding the efficacy and safety of roxadustat for the treatment of anemia in patients with chronic kidney disease who are not undergoing dialysis. METHODS: In this phase 3 trial conducted at 29 sites in China, we randomly assigned 154 patients with chronic kidney disease in a 2:1 ratio to receive roxadustat or placebo three times a week for 8 weeks in a double-blind manner. All the patients had a hemoglobin level of 7.0 to 10.0 g per deciliter at baseline. The randomized phase of the trial was followed by an 18-week open-label period in which all the patients received roxadustat; parenteral iron was withheld. The primary end point was the mean change from baseline in the hemoglobin level, averaged over weeks 7 through 9. RESULTS: During the primary-analysis period, the mean (±SD) change from baseline in the hemoglobin level was an increase of 1.9±1.2 g per deciliter in the roxadustat group and a decrease of 0.4±0.8 g per deciliter in the placebo group (P<0.001). The mean reduction from baseline in the hepcidin level (associated with greater iron availability) was 56.14±63.40 ng per milliliter in the roxadustat group and 15.10±48.06 ng per milliliter in the placebo group. The reduction from baseline in the total cholesterol level was 40.6 mg per deciliter in the roxadustat group and 7.7 mg per deciliter in the placebo group. Hyperkalemia and metabolic acidosis occurred more frequently in the roxadustat group than in the placebo group. The efficacy of roxadustat in hemoglobin correction and maintenance was maintained during the 18-week open-label period. CONCLUSIONS: In Chinese patients with chronic kidney disease who were not undergoing dialysis, those in the roxadustat group had a higher mean hemoglobin level than those in the placebo group after 8 weeks. During the 18-week open-label phase of the trial, roxadustat was associated with continued efficacy. (Funded by FibroGen and FibroGen [China] Medical Technology Development; ClinicalTrials.gov number, NCT02652819.).


Asunto(s)
Anemia/tratamiento farmacológico , Glicina/análogos & derivados , Hemoglobinas/análisis , Prolina Dioxigenasas del Factor Inducible por Hipoxia/antagonistas & inhibidores , Isoquinolinas/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Acidosis/inducido químicamente , Adulto , Anciano , Anemia/etiología , Colesterol/sangre , Método Doble Ciego , Femenino , Glicina/efectos adversos , Glicina/uso terapéutico , Hematínicos/efectos adversos , Hematínicos/uso terapéutico , Humanos , Hiperpotasemia/inducido químicamente , Isoquinolinas/efectos adversos , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/sangre
6.
N Engl J Med ; 381(11): 1011-1022, 2019 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-31340116

RESUMEN

BACKGROUND: Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis and regulates iron metabolism. Additional data are needed regarding the effectiveness and safety of roxadustat as compared with standard therapy (epoetin alfa) for the treatment of anemia in patients undergoing dialysis. METHODS: In a trial conducted in China, we randomly assigned (in a 2:1 ratio) patients who had been undergoing dialysis and erythropoiesis-stimulating agent therapy with epoetin alfa for at least 6 weeks to receive roxadustat or epoetin alfa three times per week for 26 weeks. Parenteral iron was withheld except as rescue therapy. The primary end point was the mean change in hemoglobin level from baseline to the average level during weeks 23 through 27. Noninferiority of roxadustat would be established if the lower boundary of the two-sided 95% confidence interval for the difference between the values in the roxadustat group and epoetin alfa group was greater than or equal to -1.0 g per deciliter. Patients in each group had doses adjusted to reach a hemoglobin level of 10.0 to 12.0 g per deciliter. Safety was assessed by analysis of adverse events and clinical laboratory values. RESULTS: A total of 305 patients underwent randomization (204 in the roxadustat group and 101 in the epoetin alfa group), and 256 patients (162 and 94, respectively) completed the 26-week treatment period. The mean baseline hemoglobin level was 10.4 g per deciliter. Roxadustat led to a numerically greater mean (±SD) change in hemoglobin level from baseline to weeks 23 through 27 (0.7±1.1 g per deciliter) than epoetin alfa (0.5±1.0 g per deciliter) and was statistically noninferior (difference, 0.2±1.2 g per deciliter; 95% confidence interval [CI], -0.02 to 0.5). As compared with epoetin alfa, roxadustat increased the transferrin level (difference, 0.43 g per liter; 95% CI, 0.32 to 0.53), maintained the serum iron level (difference, 25 µg per deciliter; 95% CI, 17 to 33), and attenuated decreases in the transferrin saturation (difference, 4.2 percentage points; 95% CI, 1.5 to 6.9). At week 27, the decrease in total cholesterol was greater with roxadustat than with epoetin alfa (difference, -22 mg per deciliter; 95% CI, -29 to -16), as was the decrease in low-density lipoprotein cholesterol (difference, -18 mg per deciliter; 95% CI, -23 to -13). Roxadustat was associated with a mean reduction in hepcidin of 30.2 ng per milliliter (95% CI, -64.8 to -13.6), as compared with 2.3 ng per milliliter (95% CI, -51.6 to 6.2) in the epoetin alfa group. Hyperkalemia and upper respiratory infection occurred at a higher frequency in the roxadustat group, and hypertension occurred at a higher frequency in the epoetin alfa group. CONCLUSIONS: Oral roxadustat was noninferior to parenteral epoetin alfa as therapy for anemia in Chinese patients undergoing dialysis. (Funded by FibroGen and FibroGen [China] Medical Technology Development; ClinicalTrials.gov number, NCT02652806.).


Asunto(s)
Anemia/tratamiento farmacológico , Epoetina alfa/uso terapéutico , Glicina/análogos & derivados , Hematínicos/uso terapéutico , Hemoglobinas/análisis , Prolina Dioxigenasas del Factor Inducible por Hipoxia/antagonistas & inhibidores , Isoquinolinas/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Adulto , Anciano , Análisis de Varianza , Anemia/etiología , Colesterol/sangre , Método Doble Ciego , Epoetina alfa/efectos adversos , Femenino , Glicina/efectos adversos , Glicina/uso terapéutico , Hematínicos/efectos adversos , Humanos , Hiperpotasemia/inducido químicamente , Hipertensión/inducido químicamente , Isoquinolinas/efectos adversos , Masculino , Persona de Mediana Edad , Diálisis Renal , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/terapia
7.
Am J Hematol ; 97(2): 174-184, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34724251

RESUMEN

Anemia is the predominant cytopenia in myelodysplastic syndromes (MDS) and treatment options are limited. Roxadustat is a hypoxia-inducible factor prolyl hydroxylase inhibitor approved for the treatment of anemia of chronic kidney disease in the UK, EU, China, Japan, South Korea, and Chile. MATTERHORN is a phase 3, randomized, double-blind, placebo-controlled study to assess the efficacy and safety of roxadustat in anemia of lower risk-MDS. Eligible patients had baseline serum erythropoietin ≤ 400 mIU/mL, and a low packed RBC transfusion burden. In this open-label (OL), dose-selection, lead-in phase, enrolled patients were assigned to 1 of 3 roxadustat starting doses (n = 8 each): 1.5, 2.0, and 2.5 mg/kg. The primary efficacy endpoint of the OL phase was the proportion of patients with transfusion independence (TI) for ≥ 8 consecutive weeks in the first 28 treatment weeks. A secondary efficacy endpoint was the proportion of patients with a ≥ 50% reduction in RBC transfusions over an 8-week period compared with baseline. Adverse events were monitored. Patients were followed for 52 weeks. Of the 24 treated patients, TI was achieved in 9 patients (37.5%) at 28 and 52 weeks; 7 of these patients were receiving 2.5 mg/kg dose when TI was achieved. A ≥ 50% reduction in RBC transfusions was achieved in 54.2% and 58.3% of patients at 28 and 52 weeks, respectively. Oral roxadustat dosed thrice weekly was well tolerated. There were no fatalities or progression to acute myeloid leukemia. Based on these outcomes, 2.5 mg/kg was the chosen starting roxadustat dose for the ongoing double-blind study phase.


Asunto(s)
Anemia/complicaciones , Anemia/tratamiento farmacológico , Glicina/análogos & derivados , Isoquinolinas/uso terapéutico , Síndromes Mielodisplásicos/complicaciones , Anciano , Método Doble Ciego , Femenino , Glicina/administración & dosificación , Glicina/efectos adversos , Glicina/uso terapéutico , Humanos , Isoquinolinas/administración & dosificación , Isoquinolinas/efectos adversos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/tratamiento farmacológico , Efecto Placebo , Resultado del Tratamiento
8.
Nephrol Dial Transplant ; 36(9): 1717-1730, 2021 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-33629100

RESUMEN

BACKGROUND: We evaluated the efficacy and safety of roxadustat versus epoetin alfa for the treatment of chronic kidney disease-related anemia in patients new to dialysis. METHODS: HIMALAYAS was a Phase 3, open-label, epoetin alfa-controlled trial. Eligible adults were incident to hemodialysis/peritoneal dialysis for 2 weeks to ≤4 months prior to randomization and had mean hemoglobin (Hb) ≤10.0 g/dL. Primary endpoints were mean Hb (g/dL) change from baseline averaged over Weeks 28-52 regardless of rescue therapy [non-inferiority criterion: lower limit of 95% confidence interval (CI) for treatment difference >-0.75] and percentage of patients achieving an Hb response between Weeks 1 and 24 censored for rescue therapy (non-inferiority margin for between-group difference -15%). Adverse events were monitored. RESULTS: The intent-to-treat population included patients randomized to roxadustat (n = 522) or epoetin alfa (n = 521). Mean (standard deviation) Hb changes from baseline averaged over Weeks 28-52 were 2.57 (1.27) and 2.36 (1.21) in the roxadustat and epoetin alfa groups. Roxadustat was non-inferior [least squares mean difference: 0.18 (95% CI 0.08, 0.29)] to epoetin alfa. Percentages of patients with an Hb response were 88.2% and 84.4% in the roxadustat and epoetin alfa groups, respectively. Roxadustat was non-inferior to epoetin alfa [treatment-group difference 3.5% (95% CI -0.7%, 7.7%)]. Adverse event rates were comparable between treatment groups. CONCLUSIONS: Roxadustat was efficacious for correcting and maintaining Hb levels compared with epoetin alfa. Roxadustat had an acceptable safety profile.


Asunto(s)
Anemia , Eritropoyetina , Hematínicos , Fallo Renal Crónico , Anemia/tratamiento farmacológico , Anemia/etiología , Epoetina alfa/uso terapéutico , Eritropoyetina/uso terapéutico , Glicina/análogos & derivados , Hematínicos/uso terapéutico , Hemoglobinas , Humanos , Isoquinolinas , Proteínas Recombinantes , Diálisis Renal
9.
Int Endod J ; 54(8): 1317-1327, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33711171

RESUMEN

AIM: To explore the proliferation, adhesion and differentiation response and the underlying mechanisms that occur in lipopolysaccharide (LPS)-induced inflamed dental pulp cells (DPCs) in contact with Biodentine and mineral trioxide aggregate (MTA). METHODOLOGY: The DPCs were isolated from three healthy donors and named DPC-H1 to DPC-H3. The DPCs were pre-cultured with 2 or 5 µg mL-1 LPS for 24 h to induce inflammation. The expression of inflammation marker miR-146a was detected by q-PCR. The normal and LPS-induced DPCs were further treated with 0.14 mg mL-1 Biodentine or 0.13 mg mL-1 MTA for 24 h. MTT assay and adhesion assay were used to analyse the changes of cell phenotypes. DSPP, AKT and ERK expressions were detected by Western blotting. The data were analysed by Mann-Whitney test or two-way anova. Differences were considered statistically significant when P < 0.05. RESULTS: In LPS-induced DPCs, Biodentine and MTA treatment neither induced nor aggravated LPS-induced inflammation, but their presence did increase the expression of the odontogenic differentiation marker DSPP. Under 2 or 5 µg mL-1 LPS-induced inflammation, Biodentine and MTA promoted the proliferation of DPC cells, and significantly in DPC-H2 (P < 0.0001 for both reagents). With the treatment of 2 µg mL-1 LPS, the cell adhesion of DPCs on the fibronectin-coated culture plates was increased significantly by Biodentine (P = 0.0413) and MTA (P < 0.0001). Biodentine and MTA regulated cell adhesion on the fibronectin-coated culture plates (P < 0.0001 for both reagents) and proliferation (P < 0.0001 for both reagents) via the AKT pathway. However, the AKT pathway was not involved in the expression of DSPP induced by Biodentine and MTA. CONCLUSION: Biodentine and MTA enhanced the proliferation, adhesion and differentiation of LPS-induced DPCs. The proliferation and adhesion process induced by Biodentine and MTA was via the AKT pathway. However, the cellular differentiation process might not use the same pathway, and this needs to be explored in future studies.


Asunto(s)
Pulpa Dental , Lipopolisacáridos , Compuestos de Aluminio/farmacología , Compuestos de Calcio/farmacología , Combinación de Medicamentos , Lipopolisacáridos/farmacología , Óxidos/farmacología , Silicatos/farmacología
10.
Magn Reson Med ; 83(5): 1863-1874, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31729078

RESUMEN

PURPOSE: To apply deep convolution neural network to the segmentation task in myocardial arterial spin labeled perfusion imaging and to develop methods that measure uncertainty and that adapt the convolution neural network model to a specific false-positive versus false-negative tradeoff. METHODS: The Monte Carlo dropout U-Net was trained on data from 22 subjects and tested on data from 6 heart transplant recipients. Manual segmentation and regional myocardial blood flow were available for comparison. We consider 2 global uncertainty measures, named "Dice uncertainty" and "Monte Carlo dropout uncertainty," which were calculated with and without the use of manual segmentation, respectively. Tversky loss function with a hyperparameter ß was used to adapt the model to a specific false-positive versus false-negative tradeoff. RESULTS: The Monte Carlo dropout U-Net achieved a Dice coefficient of 0.91 ± 0.04 on the test set. Myocardial blood flow measured using automatic segmentations was highly correlated to that measured using the manual segmentation (R2 = 0.96). Dice uncertainty and Monte Carlo dropout uncertainty were in good agreement (R2 = 0.64). As ß increased, the false-positive rate systematically decreased and false-negative rate systematically increased. CONCLUSION: We demonstrate the feasibility of deep convolution neural network for automatic segmentation of myocardial arterial spin labeling, with good accuracy. We also introduce 2 simple methods for assessing model uncertainty. Finally, we demonstrate the ability to adapt the convolution neural network model to a specific false-positive versus false-negative tradeoff. These findings are directly relevant to automatic segmentation in quantitative cardiac MRI and are broadly applicable to automatic segmentation problems in diagnostic imaging.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Humanos , Imagen por Resonancia Magnética , Miocardio , Incertidumbre
11.
Public Health ; 185: 31-33, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32526560

RESUMEN

OBJECTIVES: Families are a transmission route for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) because of the close contact. Monitoring of the viral load will be a valuable method to reduce the optimal number of quarantine days, especially in presymptomatic and symptomatic carriers of their households. The traditional three-generation families living together are seen frequently in East Asia, including in Taiwan. STUDY DESIGN: We report on a family cluster with six individuals infected with coronavirus disease in Taiwan. METHODS: The current public policy in Taiwan is quarantine for at least 14 days, based on the incubation period, or until the patient has tested negative three days in a row using the SARS-CoV-2 reverse transcription polymerase chain reaction. Details on the onset date of clinical symptoms, throat swab conversion, and course of disease were collected from medical records retrospectively. RESULTS: In the household of this three-generation Taiwanese family, the infection rate was 60%. The ratio of males to females was 4:2, and the age range was 11-85 years. The prevalence of asymptomatic disease was 33.3% (2/6). The longest throat swab conversion time was 37 days, and the estimated course of disease from symptoms to first conversion of throat swab was 59 days. CONCLUSIONS: Large families, including three-generation families in a single dwelling, should be monitored when the index case is found. Presymptomatic and symptomatic family members could be quarantined for an appropriate duration which, in our experience, is 2 months.


Asunto(s)
Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Familia , Pandemias/prevención & control , Neumonía Viral/prevención & control , Neumonía Viral/transmisión , Cuarentena/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19 , Niño , Infecciones por Coronavirus/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neumonía Viral/epidemiología , Estudios Retrospectivos , Taiwán/epidemiología , Factores de Tiempo , Adulto Joven
12.
J Cardiovasc Magn Reson ; 20(1): 45, 2018 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-29961424

RESUMEN

BACKGROUND: Following acute myocardial infarction (AMI), microvascular integrity and function may be compromised as a result of microvascular obstruction (MVO) and vasodilator dysfunction. It has been observed that both infarcted and remote myocardial territories may exhibit impaired myocardial blood flow (MBF) patterns associated with an abnormal vasodilator response. Arterial spin labeled (ASL) CMR is a novel non-contrast technique that can quantitatively measure MBF. This study investigates the feasibility of ASL-CMR to assess MVO and vasodilator response in swine. METHODS: Thirty-one swine were included in this study. Resting ASL-CMR was performed on 24 healthy swine (baseline group). A subset of 13 swine from the baseline group underwent stress ASL-CMR to assess vasodilator response. Fifteen swine were subjected to a 90-min left anterior descending (LAD) coronary artery occlusion followed by reperfusion. Resting ASL-CMR was performed post-AMI at 1-2 days (N = 9, of which 6 were from the baseline group), 1-2 weeks (N = 8, of which 4 were from the day 1-2 group), and 4 weeks (N = 4, of which 2 were from the week 1-2 group). Resting first-pass CMR and late gadolinium enhancement (LGE) were performed post-AMI for reference. RESULTS: At rest, regional MBF and physiological noise measured from ASL-CMR were 1.08 ± 0.62 and 0.15 ± 0.10 ml/g/min, respectively. Regional MBF increased to 1.47 ± 0.62 ml/g/min with dipyridamole vasodilation (P < 0.001). Significant reduction in MBF was found in the infarcted region 1-2 days, 1-2 weeks, and 4 weeks post-AMI compared to baseline (P < 0.03). This was consistent with perfusion deficit seen on first-pass CMR and with MVO seen on LGE. There were no significant differences between measured MBF in the remote regions pre and post-AMI (P > 0.60). CONCLUSIONS: ASL-CMR can assess vasodilator response in healthy swine and detect significant reduction in regional MBF at rest following AMI. ASL-CMR is an alternative to gadolinium-based techniques for assessment of MVO and microvascular integrity within infarcted, as well as salvageable and remote myocardium. This has the potential to provide early indications of adverse remodeling processes post-ischemia.


Asunto(s)
Circulación Coronaria , Vasos Coronarios/diagnóstico por imagen , Imagen por Resonancia Cinemagnética/métodos , Microcirculación , Microvasos/diagnóstico por imagen , Infarto del Miocardio/diagnóstico por imagen , Marcadores de Spin , Vasodilatación , Animales , Circulación Coronaria/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/fisiopatología , Dipiridamol/administración & dosificación , Modelos Animales de Enfermedad , Estudios de Factibilidad , Femenino , Microcirculación/efectos de los fármacos , Microvasos/efectos de los fármacos , Microvasos/fisiopatología , Infarto del Miocardio/fisiopatología , Valor Predictivo de las Pruebas , Sus scrofa , Vasodilatación/efectos de los fármacos , Vasodilatadores/administración & dosificación
13.
Indoor Air ; 2018 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-29855107

RESUMEN

This study determines the relative survival (RS) of Bacillus subtilis spores loaded on an N95 filtering facepiece respirator (FFR) after decontamination by five methods under worst-case conditions. Relative survival was obtained by testing after decontamination and after storing the FFRs at 37°C and 95% relative humidity for 24 hours. The decontamination methods involved ethanol, bleach, ultraviolet irradiation (UVA 365 nm, UVC 254 nm), an autoclave, and a traditional electric rice cooker (TERC) that was made in Taiwan. Without decontamination, 59 ± 8% of the loaded spores survived for 24 hours. When 70% ethanol was added to the N95 FFR at a packing density of 0.23, the RS was 73 ± 5% initially and decayed to 22 ± 8% in 24 hours. Relative survival remained above 20% after 20 minutes of UVA irradiation. The other four decontamination measures achieved 99%-100% biocidal efficacy, as measured immediately after the methods were applied to the test FFRs. Relative survival is a useful parameter for measuring sterilization or degree of disinfection. Bleach, UVC, an autoclave, and a TERC provide better biocidal efficacy than ethanol and UVA. Not only a higher filter quality but also a lower value of RS produced the most decontaminated FFR.

14.
J Neuroeng Rehabil ; 12: 36, 2015 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-25885438

RESUMEN

BACKGROUND: Recently, much attention has been given to the use of inertial sensors for remote monitoring of individuals with limited mobility. However, the focus has been mostly on the detection of symptoms, not specific activities. The objective of the present study was to develop an automated recognition and segmentation algorithm based on inertial sensor data to identify common gross motor patterns during activity of daily living. METHOD: A modified Time-Up-And-Go (TUG) task was used since it is comprised of four common daily living activities; Standing, Walking, Turning, and Sitting, all performed in a continuous fashion resulting in six different segments during the task. Sixteen healthy older adults performed two trials of a 5 and 10 meter TUG task. They were outfitted with 17 inertial motion sensors covering each body segment. Data from the 10 meter TUG were used to identify pertinent sensors on the trunk, head, hip, knee, and thigh that provided suitable data for detecting and segmenting activities associated with the TUG. Raw data from sensors were detrended to remove sensor drift, normalized, and band pass filtered with optimal frequencies to reveal kinematic peaks that corresponded to different activities. Segmentation was accomplished by identifying the time stamps of the first minimum or maximum to the right and the left of these peaks. Segmentation time stamps were compared to results from two examiners visually segmenting the activities of the TUG. RESULTS: We were able to detect these activities in a TUG with 100% sensitivity and specificity (n = 192) during the 10 meter TUG. The rate of success was subsequently confirmed in the 5 meter TUG (n = 192) without altering the parameters of the algorithm. When applying the segmentation algorithms to the 10 meter TUG, we were able to parse 100% of the transition points (n = 224) between different segments that were as reliable and less variable than visual segmentation performed by two independent examiners. CONCLUSIONS: The present study lays the foundation for the development of a comprehensive algorithm to detect and segment naturalistic activities using inertial sensors, in hope of evaluating automatically motor performance within the detected tasks.


Asunto(s)
Acelerometría/instrumentación , Algoritmos , Actividad Motora/fisiología , Actividades Cotidianas , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Sensibilidad y Especificidad
15.
Nano Lett ; 14(11): 6275-80, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-25310177

RESUMEN

Low-resistivity metal-semiconductor (M-S) contact is one of the urgent challenges in the research of 2D transition metal dichalcogenides (TMDs). Here, we report a chloride molecular doping technique which greatly reduces the contact resistance (Rc) in the few-layer WS2 and MoS2. After doping, the Rc of WS2 and MoS2 have been decreased to 0.7 kΩ·µm and 0.5 kΩ·µm, respectively. The significant reduction of the Rc is attributed to the achieved high electron-doping density, thus a significant reduction of Schottky barrier width. As a proof-of-concept, high-performance few-layer WS2 field-effect transistors (FETs) are demonstrated, exhibiting a high drain current of 380 µA/µm, an on/off ratio of 4 × 10(6), and a peak field-effect mobility of 60 cm(2)/(V·s). This doping technique provides a highly viable route to diminish the Rc in TMDs, paving the way for high-performance 2D nanoelectronic devices.

16.
J Occup Environ Hyg ; 12(11): 795-803, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26023811

RESUMEN

The southwest region of the United States is expected to experience an expansion of commercial solar photovoltaic generation facilities over the next 25 years. A solar facility converts direct current generated by the solar panels to three-phase 60-Hz power that is fed to the grid. This conversion involves sequential processing of the direct current through an inverter that produces low-voltage three-phase power, which is stepped up to distribution voltage (∼12 kV) through a transformer. This study characterized magnetic and electric fields between the frequencies of 0 Hz and 3 GHz at two facilities operated by the Southern California Edison Company in Porterville, CA and San Bernardino, CA. Static magnetic fields were very small compared to exposure limits established by IEEE and ICNIRP. The highest 60-Hz magnetic fields were measured adjacent to transformers and inverters, and radiofrequency fields from 5-100 kHz were associated with the inverters. The fields measured complied in every case with IEEE controlled and ICNIRP occupational exposure limits. In all cases, electric fields were negligible compared to IEEE and ICNIRP limits across the spectrum measured and when compared to the FCC limits (≥0.3 MHz).


Asunto(s)
Campos Electromagnéticos , Centrales Eléctricas , Ondas de Radio , Energía Solar , California , Exposición a Riesgos Ambientales , Exposición Profesional , Dosis de Radiación
17.
Phys Chem Chem Phys ; 16(14): 6539-43, 2014 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-24569809

RESUMEN

We present a Raman spectroscopy study of electron-phonon coupling in In0.53Ga0.47As epilayers doped via the sulfur-monolayer doping method. A high-frequency coupled mode (HFCM) detected above 400 cm(-1) shifts with increasing charge carrier density and allows for extraction of the activated dopant concentrations.

18.
Microbiol Resour Announc ; : e0014724, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916300

RESUMEN

Reported here are the sequences for 11 Escherichia coli and four Enterococcus strains isolated from post-menopausal women with a recurrent urinary tract infection. Each of the Enterococcus strains were isolated along with an E. coli strain. This provides a resource of high-quality complete genomes from polymicrobial infections.

19.
World J Pediatr Congenit Heart Surg ; 15(3): 287-297, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38263638

RESUMEN

BACKGROUND: This article aims to demonstrate the morphology of 261 total anomalous pulmonary venous connection (TAPVC) cases operated at Children's Hospital 1 with in-hospital mortality of 19.5% (51/261). METHODS: All the surgical protocols of TAPVC cases repaired between 2008 and June 2023 were reviewed. The descriptions of TAPVC were based on operative findings by surgeons. RESULTS: A total of 261 TAPVC patients were operated, including 124 (47.5%) supra, 83 (31.8%) intra, 41 (15.7%) infra, and 13 (5%) mixed cases. The in-hospital mortality was 19.5% (51/261). Fifteen cases are associated with other anomalies of the heart. Four subtypes of 124 supra TAPVC were found, with 42 (33.9%) obstructed cases. The standard was all pulmonary veins (PVs) forming a common vein (CV) and draining into the innominate veins, then going to the superior vena cava (SVC) (100/124, 80.6%). Eleven supra TAPVC cases were vascular vise type. Ten cases had the vertical vein running from the right of the CV and draining directly into the SVC. Of 83 intracardiac TAPVCs with 9 (10.8%) obstructed cases, the most common was all PVs draining directly into the coronary sinus (60/83, 72.3%). The second was all PVs draining directly into the right atrium (RA) via separated ostia or forming a CV before entering the RA (17/83, 20.5%). Also, there were three cases with rare variants and 100% obstruction when the diagnosis was explored. The in-hospital mortality of intracardiac type was 13.3% (11/83) 41 infra TAPVC with obstructed rate of 61% (25/41) and in-hospital mortality of 29.3% (12/41). Thirteen mixed TAPVCs were repaired, with most cases having three PVs forming a CV. CONCLUSION: This article provides valuable information about the morphology of TAPVC types in Asian patients.


Asunto(s)
Mortalidad Hospitalaria , Venas Pulmonares , Síndrome de Cimitarra , Humanos , Femenino , Masculino , Síndrome de Cimitarra/cirugía , Síndrome de Cimitarra/mortalidad , Vietnam/epidemiología , Estudios Retrospectivos , Venas Pulmonares/anomalías , Venas Pulmonares/cirugía , Lactante , Recién Nacido , Preescolar , Procedimientos Quirúrgicos Cardíacos/métodos , Niño
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