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1.
Artigo em Inglês | MEDLINE | ID: mdl-34591778

RESUMO

BACKGROUND: Contact tracing and intensive testing programmes are essential for COVID-19 control. However, conventional contact tracing is resource intensive and is unable to trace all the cases due to recall bias and anonymity of a number of close contacts. So far, few studies have reported the epidemiological features of cases not identified from contact tracing ("unlinked cases") or described their potential roles in seeding community outbreaks. OBJECTIVE: Here we characterized the role of unlinked cases in the epidemic by comparing their epidemiological profile with the linked cases and estimated their transmission potential across different settings. METHODS: We obtained the government rapid surveillance data containing the line-listing of COVID-19 confirmed cases accounting for the first three waves in Hong Kong. We compared the demographics, history of chronic illnesses, epidemiological characteristics, clinical characteristics, and outcomes between linked and unlinked cases. Transmission potentials at different settings were assessed by fitting a negative binomial distribution to the observed offspring distribution. RESULTS: Time interval from illness onset to hospital admission was longer among unlinked cases than the linked (median: 5.00 vs 3.78 days; P<.001), with a higher proportion experiencing critical or serious conditions (13.0% vs 8.2%; P<.001). The proportion of unlinked cases was associated with the increase of the weekly number of local cases (P=.049). Cluster transmissions from the unlinked cases were most frequently identified in household settings, followed by eateries and workplaces, with the estimated probability of cluster transmissions being around 0.4 for households and 0.1-0.3 for the latter two settings. CONCLUSIONS: The unlinked cases were positively associated with the time to hospital admission, severity of infection, and epidemic size - implying a need to design and implement digital tracing methods to complement current conventional testing and tracing. To minimize the risk of cluster transmissions from unlinked cases, digital tracing approaches should be effectively applied in high-risk socio-economic settings, and risk assessment conducted to review and adjust the policies.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34484618

RESUMO

Background: Severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19) have caused substantial public health burdens and global health threats. Understanding the superspreading potential of a virus is important for characterizing transmission patterns and informing strategic decision-making in disease control. This systematic review aimed to summarize the existing evidence on superspreading features and to compare the heterogeneity in transmission within and among various coronavirus epidemics of SARS, MERS and COVID-19. Methods: PubMed, Medline, and Embase databases were extensively searched for original studies on the transmission heterogeneity of SARS, MERS, and COVID-19 published in English between January 1, 2003, and February 10, 2021. After screening the articles, we extracted data pertaining to the estimated dispersion parameter (k) which has been a commonly-used measurement for transmission heterogeneity and superspreading potential.FindingsWe included a total of 60 estimates of transmission heterogeneity from 26 studies on outbreaks in 22 regions. The majority (90%) of the k estimates were small, with values less than 1, indicating an over-dispersed transmission pattern. The point estimates of k for SARS and MERS ranged from 0.12 to 0.20 and from 0.06 to 2.94, respectively. Among 45 estimates of individual-level transmission heterogeneity for COVID-19 from 17 articles, 91% were derived from Asian regions. The point estimates of k for COVID-19 ranged between 0.1 and 5.0. Conclusions: We detected a substantial over-dispersed transmission pattern in all three coronaviruses, while the k estimates varied by differences in study design and public health capacity. Our findings suggested that even with a reduced R value, the epidemic still has a high resurgence potential due to transmission heterogeneity.

3.
J Theor Biol ; 529: 110861, 2021 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-34390731

RESUMO

One of the key epidemiological characteristics that shape the transmission of coronavirus disease 2019 (COVID-19) is the serial interval (SI). Although SI is commonly considered following a probability distribution at a population scale, recent studies reported a slight shrinkage (or contraction) of the mean of effective SI across transmission generations or over time. Here, we develop a likelihood-based statistical inference framework with truncation to explore the change in SI across transmission generations after adjusting the impacts of case isolation. The COVID-19 contact tracing surveillance data in Hong Kong are used for exemplification. We find that for COVID-19, the mean of individual SI is likely to shrink with a factor at 0.72 per generation (95%CI: 0.54, 0.96) as the transmission generation increases, where a threshold may exist as the lower boundary of this shrinking process. We speculate that one of the probable explanations for the shrinkage in SI might be an outcome due to the competition among multiple candidate infectors within the same case cluster. Thus, the nonpharmaceutical interventive strategies are crucially important to block the transmission chains, and mitigate the COVID-19 epidemic.


Assuntos
COVID-19 , Busca de Comunicante , Hong Kong , Humanos , Funções Verossimilhança , SARS-CoV-2
4.
Medicine (Baltimore) ; 100(32): e26756, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34397878

RESUMO

BACKGROUND: A rapid lateral flow test (Peptest) to detect pepsin in saliva/sputum has been considered as a valuable method for diagnosing laryngopharyngeal reflux (LPR) and gastroesophageal reflux disease (GERD). The aim of this meta-analysis is to analyze the utility of Peptest for diagnosis of LPR and GERD. METHODS: PubMed, EMBASE, and the Cochran Library (from January 1980 to 26 January 2020) were searched for pepsin in saliva for LPR/GERD diagnosis. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve data were summarized to examine the accuracy. RESULTS: A total of 16 articles that included 2401 patients and 897 controls were analyzed. The pooled sensitivity and specificity for the diagnosis of GERD/LPR with Peptest were 62% (95% confidence interval [CI] 49%-73%) and 74% (95% CI 50%-90%), respectively. The summarized diagnostic odds ratio and area under the curve were 5.0 (95% CI 2-19) and 0.70 (95% CI 0.66-0.74), respectively. CONCLUSION: Peptest shows moderate diagnostic value for LPR and GERD. More studies with standard protocols should be done to verify its usefulness.


Assuntos
Refluxo Gastroesofágico/diagnóstico , Refluxo Laringofaríngeo/diagnóstico , Pepsina A/metabolismo , Saliva/metabolismo , Biomarcadores/metabolismo , Diagnóstico Diferencial , Refluxo Gastroesofágico/metabolismo , Humanos , Refluxo Laringofaríngeo/metabolismo , Curva ROC
5.
Sci Rep ; 11(1): 15076, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301972

RESUMO

Gastroesophageal flap valve (GEFV) grading is a simple and reproducible parameter. There is limited information about the association between GEFV abnormality and novel parameters in patients with gastroesophageal reflux disease(GERD) symptoms by the Lyon Consensus. To investigate the value of GEFV grading in GERD, the clinical data of 320 patients with GERD symptoms who underwent endoscopy, 24-h multichannel intraluminal impedance-pH (MII-pH) monitoring, and high-resolution manometry (HRM) were retrospectively analyzed. The percentage of acid exposure time (AET%)(4.2 [1.5-7.4] vs. 1.3 [0.3-4.2], P < 0.001) and the proportion of abnormal esophagogastric junction (EGJ) morphology (71 [87.7%] vs. 172 [72.0%], P = 0.011) were significantly higher, while the mean nocturnal baseline impedance (MNBI) (2068.3 [1658.4-2432.4] vs. 2228.5 [1794.8-2705.3]Ω, P = 0.012) and post-reflux swallow-induced peristaltic wave index (PSPWI) (19.7 [13.9-29.0] vs. 33.3 [25.0-44.0]%, P < 0.001) were significantly lower in the abnormal GEFV group compared with the normal GEFV group. AET% and EGJ morphology showed positive correlations with GEFV grade, while PSPWI and MNBI showed negative correlations. Patients with an abnormal GEFV had a significantly greater risk of conclusive evidence of GERD compared to those with a normal GEFV (OR 3.035, 95% CI 1.758-5.240, P < 0.001). Further, when identifying patients with conclusive evidence of GERD, abnormal GEFV had a specificity of 80.4% (95% CI 75.3-85.5%). GEFV grading might be regarded as supportive evidence for GERD diagnosis.

6.
ACS Appl Mater Interfaces ; 13(20): 24062-24069, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33977715

RESUMO

Flexible pressure sensors have emerged as an indispensable part of wearable devices due to their application in physiological activity monitoring. To realize long-term on-body service, they are increasingly required for properties of conformability, air permeability, and durability. However, the enhancement of sensitivity remains a challenge for ultrathin capacitive sensors, particularly in the low-pressure region. Here, we introduced a highly sensitive and ultrathin capacitive pressure sensor based on a breathable all-fabric network with a micropatterned nanofiber dielectric layer, an all-fabric capacitive sensor (AFCS). This all-fabric network endows a series of exceptional performances, such as high sensitivity (8.31 kPa-1 under 1 kPa), ultralow detection limit (0.5 Pa), wide detection range (0.5 Pa to 80 kPa), and excellent robustness (10 000 dynamic cycles). Besides, the all-fabric structure provides other properties for the AFCS, e.g., high skin conformability, super thinness (dozens of micrometers), and exceptional air permeability. Our AFCS shows promising potential in breathing track, muscle activity detection, fingertip pressure monitoring, and spatial pressure distribution, paving way for comfortable skinlike epidermal electronics.


Assuntos
Monitorização Fisiológica/instrumentação , Nanofibras/química , Dispositivos Eletrônicos Vestíveis , Capacitância Elétrica , Desenho de Equipamento , Humanos , Sensibilidade e Especificidade
7.
Chemistry ; 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33830540

RESUMO

Achieving self-assembled nanostructures with ultra-small feature sizes (e. g., below 5 nm) is an important prerequisite for the development of block copolymer lithography. In this work, the preparation and self-assembly of a series of giant molecules composed of vinyl polyhedral oligomeric silsesquioxane (VPOSS) tethered with monodispersed oligo(L-lactide) chains are presented. Small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) results demonstrate that ultra-small domain sizes (down to 3 nm) of phase separated lamellar morphology are achieved in bulk, driven by the strong tendency and fast kinetics for crystallization of VPOSS moieties. Moreover, upon gamma ray radiation, VPOSS cages in the lamellar structure can be crosslinked via polymerization of the vinyl groups. After pyrolysis at high temperature, ultra-thin two-dimensional nano-silica sheets can be obtained.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33823580

RESUMO

Fiber-shaped Zn batteries are promising candidates for wearable electronics owing to their high energy and low cost, but further studies are still required to address the issues related to detrimental Zn dendrite growth and limited low-temperature performances. Here, we report an antifreeze, long-life, and dendrite-free fiber-shaped Zn battery using both nanoporous Zn and polyaniline (PANI) electrodeposited on carbon nanofibers (CFs) as the cathode and anode, respectively. The fiber-shaped Zn anode achieves stable plating/stripping for 1000 mAh cm-2 accumulative capacity with low polarization (30 mV) at a current density of 2 mA cm-2. The dendrite-free Zn electrodes also enable the stable cycling of the fiber battery with 75.1% capacity retention after 1000 cycles. With an antifreeze agent added in the gel electrolyte, the fiber battery maintains excellent performance at temperatures as low as -30 °C. Lastly, by utilizing the doping/dedoping mechanism of Cl- in the PANI electrode, we achieve, for the first time, a Zn battery using human sweat as a harmless electrolyte. Our work provides a long-life and antifreeze fiber-shaped battery that is highly promising for future wearable energy storage devices.

9.
J Int Soc Sports Nutr ; 18(1): 33, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33910582

RESUMO

BACKGROUND: Hong Kong is a densely populated city with a low incidence and mortality of coronavirus disease 2019 (COVID-19). The city imposed different levels of social distancing including, the closure of sports venues and restrictions on eateries. This inevitably affects the eating behaviour and physical activities of the population. We examined the changes in eating behavior and physical activities before and during the COVID-19 pandemic, and identified sociodemographic factors associated with the behavioral changes. METHODS: This was a cross-sectional study via a random telephone survey of Chinese adults conducted in Hong Kong from May to June, 2020 - a period in which social distancing measures were being imposed. We measured the physical activity habits from four aspects and dietary consumption patterns from seven aspects before and during the pandemic based on the World Health Organization's guidelines and previous publications. RESULTS: In total, 724 participants were recruited. Individuals were found to cook more frequently at home (p < 0.001) and order take-out (p < 0.001) during the COVID-19 pandemic. While no significant change in the frequency of fast food consumption was observed, we found significant increases in the frequency of eating fruits (p < 0.001) and vegetables (p = 0.004). The frequencies of walking, moderate-intensive sports, and high-intensity sports were significantly reduced (p < 0.001). We found that healthy lifestyle behaviors during the pandemic were negatively associated with participants' economic status. CONCLUSIONS: Social distancing measures likely provided an opportunity for individuals to stay home and thus eat healthier. However, in a prolonged period of social restrictions, a lower physical activity level poses a risk to public health. Public health officials are thus advised to monitor physical health on a population-wide basis. The findings highlighted the importance of interventions tailored to individuals who have prolonged home stays - particularly for individuals in the low economic group.


Assuntos
COVID-19/epidemiologia , Exercício Físico , Comportamento Alimentar , Idoso , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Inquéritos e Questionários , Telefone
11.
BMC Med Res Methodol ; 21(1): 30, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33568100

RESUMO

BACKGROUND: In infectious disease transmission dynamics, the high heterogeneity in individual infectiousness indicates that few index cases generate large numbers of secondary cases, which is commonly known as superspreading events. The heterogeneity in transmission can be measured by describing the distribution of the number of secondary cases as a negative binomial (NB) distribution with dispersion parameter, k. However, such inference framework usually neglects the under-ascertainment of sporadic cases, which are those without known epidemiological link and considered as independent clusters of size one, and this may potentially bias the estimates. METHODS: In this study, we adopt a zero-truncated likelihood-based framework to estimate k. We evaluate the estimation performance by using stochastic simulations, and compare it with the baseline non-truncated version. We exemplify the analytical framework with three contact tracing datasets of COVID-19. RESULTS: We demonstrate that the estimation bias exists when the under-ascertainment of index cases with 0 secondary case occurs, and the zero-truncated inference overcomes this problem and yields a less biased estimator of k. We find that the k of COVID-19 is inferred at 0.32 (95%CI: 0.15, 0.64), which appears slightly smaller than many previous estimates. We provide the simulation codes applying the inference framework in this study. CONCLUSIONS: The zero-truncated framework is recommended for less biased transmission heterogeneity estimates. These findings highlight the importance of individual-specific case management strategies to mitigate COVID-19 pandemic by lowering the transmission risks of potential super-spreaders with priority.


Assuntos
Distribuição Binomial , COVID-19/transmissão , Simulação por Computador , Transmissão de Doença Infecciosa/estatística & dados numéricos , Humanos , Infectologia/estatística & dados numéricos , Funções Verossimilhança , Pandemias , Vigilância da População , SARS-CoV-2 , Viés de Seleção
12.
Med Sci Monit ; 26: e927381, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33220027

RESUMO

BACKGROUND The Lyon Consensus classification confirms or rules out gastroesophageal reflux disease (GERD). The refractory symptoms of patients with GERD taking proton pump inhibitors (PPIs) are challenging in clinical practice. Salivary pepsin concentration was proposed as a diagnostic biomarker for GERD. We aimed to determine the diagnostic value of salivary pepsin concentration for patients with conclusive GERD, based on the Lyon classification, and the correlation of salivary pepsin concentration with parameters of high-resolution manometry and 24-h multichannel intraluminal impedance-pH in patients with PPI-refractory symptoms. MATERIAL AND METHODS Saliva samples obtained from 130 patients who were suspicious for GERD and had PPI-refractory symptoms were used for pepsin determination using the enzyme-linked immunosorbent assay. All patients underwent upper gastrointestinal endoscopy, high-resolution manometry, 24-h multichannel intraluminal impedance, and pH recording and were classified as conclusive GERD, inconclusive GERD, and evidence against GERD groups according to Lyon classification. RESULTS Salivary pepsin concentration was 8.2 ng/mL (3.8-17.8 ng/mL), 4.0 ng/mL (2.3-6.1 ng/mL), and 2.4 ng/mL (2.2-3.1 ng/mL) in conclusive GERD, inconclusive GERD, and evidence against GERD groups, respectively (P<0.001), and had a negative correlation with distal mean nocturnal baseline impedance and positive correlations with acid exposure time, total number of reflux events, and esophagogastric junction type. The area under the ROC curve of salivary pepsin for conclusive GERD was 0.76 (0.68-0.84), with a sensitivity of 76.36% and a specificity of 63.41% for conclusive GERD diagnosis at a cut-off value of 4.21 ng/mL. CONCLUSIONS Salivary pepsin test had moderate diagnostic value for conclusive GERD by Lyon classification in patients with PPI-refractory symptoms.


Assuntos
Impedância Elétrica , Monitoramento do pH Esofágico , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/fisiopatologia , Manometria , Pepsina A/metabolismo , Saliva/enzimologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
13.
Exp Cell Res ; 397(1): 112341, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33191205

RESUMO

Nonalcoholic fatty liver disease (NAFLD), which is characterized by aberrant accumulation of intrahepatic triglycerides and lipid droplets (LDs) in the liver cells, is becoming increasingly prevalent at an alarming rate worldwide. LDs can be consumed by either hydrolysis or autophagy, which is shown to be of importance in the regulation of hepatic lipid metabolism. We have shown that deficiency of pleckstrin homology domain-containing casein kinase 2 interacting protein-1 (CKIP-1), a scaffold protein that interacts with various proteins in multiple signal pathways, in mice aggravates high-fat diet induced fatty liver. However, its underlying mechanisms remain largely unknown. In this study, we found that the mRNA and protein levels of CKIP-1 decreased dramatically in steatotic HepG2 cells induced by oleic acid (OA) treatment. Coincidently, hepatic autophagy was also dynamically regulated in steatotic HepG2 cells. In addition, overexpression of CKIP-1 activated autophagy by suppression of Akt/mTOR signaling, which in turn reduced lipid accumulation. Moreover, these phenomena were reversed in CKIP-1-shRNA transfected steatotic hepatocytes. To further evaluate the potential role of CKIP-1 in autophagy, we determined the level of autophagy related proteins in CKIP-1 knockout mice. These results supported our findings in vitro. In summary, we found CKIP-1 to be a positive regulator of hepatic autophagy and a promising therapeutic target for treatment of NAFLD.


Assuntos
Autofagia , Proteínas de Transporte/fisiologia , Fígado Gorduroso/patologia , Hepatócitos/patologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
14.
Sci Rep ; 10(1): 9001, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32488023

RESUMO

To increase the available land area, a large-scale land remediation campaign was carried out in the loess hilly and gully area. A large number of high and steep slopes have been produced in the construction of road engineering and water conservancy engineering, and these slopes will cause serious soil erosion under rainfall conditions. Because rainfall runoff is simultaneously affected by slope, bed surface and rainfall, the runoff movement characteristics are complex. It is difficult to consider all influencing factors in the existing models, especially for steep slopes. In this study, artificial rainfall experiments were conducted to study the rainfall-runoff hydraulic processes under different rainfall intensities and slope gradients, and a modified method was proposed to model the key hydraulic parameters (i.e., equilibrium time, water surface line, and runoff processes) on steep slopes. The results showed that (1) For steep slopes (a 70° slope compared to a 5° slope), the runoff generation time, confluence time and equilibrium time of the slope decreased significantly. At the same time, the single width runoff of the steep slope had a power function relationship with the rainfall intensity and gradient. (2) The runoff patterns of steep slopes were different from those on gentle slopes and runoff patterns were more likely to change. The Reynolds number and Froude number for slope flow changed slowly when the slope was less than the critical gradient and increased significantly when the slope exceeded the critical gradient. (3) Based on the analysis of the "double turbulent model theory of thin-layer flow on a high-steep slope", combined with the dispersed motion wave model, a modified method for calculating the hydrodynamic factors of rainfall runoff was proposed. Then, this method was verified with indoor and outdoor experiments. The research results not only have theoretical significance, but also provide a more accurate calculation method for the design of high and steep slopes involved in land treatment engineering, road engineering and water conservancy engineering.

15.
J Agric Food Chem ; 68(28): 7498-7508, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32543187

RESUMO

To obtain natural protein gels as delivery systems loading with probiotics and protect the probiotics from heat treatment, we fabricated casein-based gels using micellar casein concentrates (MCC) via microfiltration and then embedded with Lactobacillus Rhamnosus GG (LGG). Rheological analysis indicated that MCC with a protein concentration of 12% would form gels greatly. The results of SDS-polyacrylamide gel electrophoresis showed that the contents of macromolecule in the gels increased as the heat treatment time is prolonged. After heat treatment, a fibrillated structure and a more stable structure were obtained in MCC-LGG gels by scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. The different changes of rheological behavior and texture of the gels were evaluated using a rheometer and texture analyzer, respectively. Similarly, centrifugation could reduce the property modified by heat inducing and contribute to LGG embedding completely. Importantly, LGG with a survival rate of 7.12% was in the gels after heat treatment at 75 °C for 10 min. Results showed that MCC could offer a protecting circumstance for living LGG cells from heat treatment. Therefore, MCC-LGG gels would be a potential healthy food for improving intestinal microflora in the dairy industry.


Assuntos
Caseínas/química , Lactobacillus rhamnosus/química , Probióticos/química , Sistemas de Liberação de Medicamentos , Filtração , Géis/química , Temperatura Alta , Micelas , Reologia
16.
Eur J Pharmacol ; 880: 173162, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32423868

RESUMO

Na+-K+-2Cl- cotransporter (NKCC) is expressed at exceptionally high levels in gastric parietal cells. Bumetanide, a potent loop diuretic that blocks NKCC, usually causes a decrease in gastric acid secretion. Endotoxaemia causes hypochlorhydria in vivo, in which lipopolysaccharide (LPS) plays an important role. This study aimed to investigate the effect of NKCC2 on gastric acid secretion and its alteration in LPS-treated mice. The scanning ion-selective electrode technique and real-time pH titration combined with RNA interference were used to determine the effects of bumetanide on gastric acid secretion. Immunochemistry and Western blotting were performed to investigate the changes in NKCC2 expression in LPS-treated mice. Immunoreactivity of NKCC1 and NKCC2 was mainly observed near the basolateral and apical membranes of parietal cells, respectively. Pretreatment with bumetanide reduced the histamine-stimulated H+ flux in the mouse gastric mucosa. The apical, but not the basolateral, addition of bumetanide inhibited forskolin- or histamine/3-isobutyl-1-methylxanthine(IBMX)-induced gastric acid secretion. In vivo treatment with NKCC2 siRNA inhibited forskolin-induced acid secretion. Upon histamine stimulation, the majority of NKCC2 was targeted to the apical membrane in the gastric mucosa and in primary cultured parietal cells. The expression of NKCC2 and vesicle-associated membrane protein-2 (VAMP2), but not that of H+/K+-ATPase, was decreased in the gastric mucosa of LPS-treated mice. Blocking apical NKCC2, but not basolateral NKCC1, by bumetanide inhibited secretagogue-induced gastric acid secretion, during which the membrane trafficking of NKCC2 may be necessary. The downregulation of NKCC2 and VAMP2 may be related to the reduced gastric acid secretion induced by LPS.


Assuntos
Bumetanida/farmacologia , Ácido Gástrico/metabolismo , Células Parietais Gástricas/efeitos dos fármacos , Secretagogos/farmacologia , Membro 1 da Família 12 de Carreador de Soluto/metabolismo , Animais , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Camundongos Endogâmicos C57BL , Células Parietais Gástricas/metabolismo , Ratos Sprague-Dawley , Proteína 2 Associada à Membrana da Vesícula/metabolismo
17.
ACS Nano ; 14(5): 5590-5599, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32369343

RESUMO

The integration between energy-harvesting and energy-storage devices into a self-charging power unit is an effective approach to address the energy bottleneck of wearable/portable/wireless smart devices. Herein, we demonstrate a stretchable coplanar self-charging power textile (SCPT) with triboelectric nanogenerators (TENGs) and microsupercapacitors (MSCs) both fabricated through a resist-dyeing-analogous method. The textile electrodes maintain excellent conductivity at 600% and 200% tensile strain along course and wale directions, respectively. The fabric in-plane MSC with reduced graphene oxides as active materials reaches a maximum areal capacitance of 50.6 mF cm-2 at 0.01 V s-1 and shows no significant degradation at 50% of tensile strain. The stretchable fabric-based TENG can output 49 V open-circuit voltage and 94.5 mW m-2 peak power density. Finally, a stretchable coplanar SCPT with one-batch resist-dyeing fabrication is demonstrated for powering small electronics intermittently without extra recharging. Our approach is also compatible with conventional textile processing and suggests great potential in electronic textiles and wearable electronics.

18.
Adv Mater ; 32(1): e1904988, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746041

RESUMO

Triboelectrification-enabled self-powered flexible electronic/optical systems have aroused a new surge of interest in recent years. All-in-one integration of such a system, which could significantly improve its adaptability, operability, and portability, still remains a challenge due to the absence of suitable architectures and integration schemes. Herein, a previously reported self-powered optical switch (OS) is thoroughly remolded and upgraded to a fully integrated contact-sliding-triboelectrification-driven dynamic optical transmittance modulator (OTM). The OTM is constructed with a multilayered structure, comprising a transparent triboelectrification top layer, a SiO2 -spaced polymer dispersed liquid crystal (PDLC) intermediate layer, and a flexible transparent conductive substrate. The working mechanism is that an alternating electric field can be induced once contact-sliding occurs upon the OTM, rendering the PDLC layer immediately switching its initial translucent state to an instantaneous transparent state. As such, a decent dimming range with the relative transmitted light intensity from 0.17 to 0.72 can be achieved at low mechanical thresholds of contact pressure (≈20 kPa) and sliding velocity (≈0.3 m s-1 ). Moreover, for practical applications, demonstrations of information covering and selective visualization are successfully implemented without any extra optical elements nor external power supplies, explicitly showing great potential for the OTM in various self-powered optical interactive applications.

19.
Medicine (Baltimore) ; 98(23): e15965, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31169725

RESUMO

BACKGROUND: Acid exposure time (AET) prolongation plays an important role in the pathogenesis of gastroesophageal reflux disease (GERD). Gastric inhibitory polypeptide (GIP) and pancreatic polypeptide (PP) participate in the regulation of gastric acid secretion, blood glucose and lipid levels, and food intake. In this study, we evaluated the serum GIP and PP levels in refractory GERD patients and analyzed their metabolic and motility characteristics. METHODS: Seventy-three refractory GERD patients were enrolled in this study from September 2015 to September 2017. We investigated the clinical characteristics, severity, and duration of GERD symptoms. High-resolution manometry and 24 hours impedance-pH monitoring were performed to assess esophageal motility and reflux parameters. The patients were divided into the AET- group (AET <4.2%) and AET+ group (AET >4.2%). GIP and PP levels were determined in all subjects and their associations with other parameters evaluated. RESULTS: Age and GERDQ score were significantly higher (P < .05) and acid reflux and heartburn more frequent in the AET+ group than in the AET- group. The contraction front velocity was increased in the AET- group, while there was no significant difference in the distal contraction integral, peristalsis interruption, distal latency, or resting pressures of the lower and upper esophageal sphincters between the 2 groups (P > .05). The serum levels of GIP (P = .003) and PP (P = .012) were significantly increased in the AET+ group. Increased GIP and PP levels were associated with abnormal upright AET (correlation coefficients 0.307 and 0.233, P = .008 and P = .047). There was a positive correlation between GIP and triglyceride levels (correlation coefficient 0.279, P = .017). CONCLUSION: The serum levels of GIP and PP in refractory GERD patients with prolongation of AET are significantly elevated, mainly in the upright position.


Assuntos
Ácido Gástrico/metabolismo , Polipeptídeo Inibidor Gástrico/sangue , Refluxo Gastroesofágico/sangue , Polipeptídeo Pancreático/sangue , Fatores de Tempo , Idoso , Impedância Elétrica , Monitoramento do pH Esofágico , Esôfago/fisiopatologia , Feminino , Refluxo Gastroesofágico/fisiopatologia , Humanos , Masculino , Manometria , Pessoa de Meia-Idade
20.
Am J Transl Res ; 11(1): 257-268, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30787984

RESUMO

Angiogenesis is an important step in skin wound repair. Angiogenesis is affected by the functions of many types of cells, especially endothelial cells. Cdc42 plays a vital role in endothelial cell function and vascular development; however, the role of Cdc42 in skin microvascular permeability and skin wound healing is unclear. This study investigated the involvement of Cdc42 in skin wound-healing processes based on its known roles in angiogenesis. Full-thickness skin wounds were created on wild-type and inducible vascular-endothelial-specific Cdc42-/- mice. Cdc42 deletion in endothelium affected wound healing in following ways. Reepithelialization of wounds in Cdc42-/- mice was delayed compared with that of wounds in wild-type mice. The degree of angiogenesis of wound granulation tissue was significantly lower in Cdc42-/- mice than in wild-type mice. Infiltration of F4/80+ macrophages and the expression of MCP-1, IL-1ß, and TNF-α were increased in the wound bed of Cdc42-/- mice compared with wild-type mice. These results confirm that Cdc42 in endothelium is required for angiogenesis and is an essential regulator of key skin wound-healing processes.

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