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1.
Clin Endocrinol (Oxf) ; 95(3): 378-389, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33662155

RESUMEN

BACKGROUND: Many studies have reported that the thyroid-stimulating hormone (TSH) reference interval is susceptible to external factors, such as age, sex, race, region and iodine intake. However, no meta-analysis has comprehensively explored the effect of these factors on the TSH reference interval. METHODS: Articles published from January 1960 to January 2020 were searched in PubMed, Embase, Cochrane, Scopus, Medline English databases and CNKI, WanFang and CQVIP Chinese databases. In total, 19 studies were ultimately included. All data were analysed using Review Manager 5.3, STATA 16.0 software, GraphPad Prism 8.0 and Microsoft Excel 2010 to draw the TSH concentration curve. RESULTS: The TSH reference interval was significantly influenced by sex and age. The mean of TSH concentration in females was 0.27 mIU/L higher than that in males. Reference interval of TSH is divided into 20-59 years old and >60 years old age groups in males, and 20-39 years old and >40 years old age groups in females. Regardless of sex, TSH concentrations all increase with age. In iodine-deficient areas, TSH reference intervals were generally lower than those in iodine-sufficient or iodine-excessive areas. The TSH reference interval in Asia and North American countries was generally higher than that in most European countries. In the subgroup analyses of sample size, region and assay methods and manufacturers, the between-group differences were significant. CONCLUSION: The TSH reference interval was significantly influenced by sex, age, iodine intake, sample size, region, and assay methods and manufacturers, but other factors should not be ignored. Therefore, it is necessary for each laboratory to validate an appropriate TSH reference interval based on local conditions.


Asunto(s)
Yodo , Tirotropina , Adulto , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Valores de Referencia , Adulto Joven
2.
Langmuir ; 37(49): 14483-14490, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-34851638

RESUMEN

Bubble dynamics plays an important role in boiling heat transfer, and surface wettability affects bubble behaviors. In the present work, the effects of surface superhydrophilicity (SHI) and superhydrophobicity (SHO) on bubble dynamics are experimentally studied by observing the formation and motion behaviors of air bubbles and vapor bubbles on varied surfaces. For air bubbles to better mimic vapor bubbles, the air bubbles are introduced in a water pool by injecting airflow from a through hole of the surface. Air bubble tests are first conducted on homogeneous SHO and SHI surfaces, respectively. It is observed that surface wettability significantly affects the bubble size and departure frequency. To discover the dynamic behaviors of a bubble under both SHI and SHO, a biphilic surface with SHI and SHO areas is fabricated, and air bubbles are injected right on the biphilic border between the two areas. It is observed the wettability contrast significantly displaces the air bubbles, which spread only onto the SHO area. The biphilic surface is fabricated for the pool boiling test. Vapor bubbles are observed at different stages of the nucleate boiling, showing surface effects similar to the observations of air bubbles. Not only does this study present the influence of surface wettability on air and vapor bubble behaviors but also it provides useful implications for understanding and optimizing the biphilic surface design for enhancing boiling heat transfer.

3.
Psychiatr Q ; 92(1): 311-320, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32661940

RESUMEN

Nonconvulsive electrotherapy (NET) defined as electrical brain stimulation administered like standard electroconvulsive therapy (ECT), but below seizure threshold, could be effective for patients with treatment-refractory depression (TRD) with fewer adverse neurocognitive outcomes. However, there is a lack of studies in Chinese patients with TRD. Thus, this study was conducted to examine the efficacy and safety of adjunctive NET for Chinese patients with TRD. Twenty TRD patients were enrolled and underwent six NET treatments. Depressive symptoms, response, and remission were assessed with the 17-item Hamilton Depression Rating Scale (HAMD-17) at baseline and after 1, 3, and 6 NET treatments. Neurocognitive function was assessed by the Wisconsin Card Sorting Test (WCST) at baseline and after the completion of six NET treatments. Mean HAMD-17 scores declined significantly from 26.2 to 10.4 (p < 0.001) after post-NET. The rates of response and remission were 60.0% (95% CI: 36.5-83.5) and 10.0% (95% CI: 0-24.4), respectively. Neurocognitive performance improved following a course of NET. No significant association was found between changes in depressive symptoms and baseline neurocognitive function. Adjunctive NET appeared to be effective for patients with TRD, without adverse neurocognitive effects. Randomized controlled studies were warranted to confirm these findings.


Asunto(s)
Trastorno Depresivo Resistente al Tratamiento/terapia , Terapia por Estimulación Eléctrica , Adulto , Femenino , Humanos , Masculino
4.
Small ; 15(2): e1803428, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30450734

RESUMEN

Self-assembled protein nanoparticles have attracted much attention in biomedicine because of their biocompatibility and biodegradability. Protein nanoparticles have become widely utilized as diagnostic or therapeutic agents for various cancers. However, there are no reports that protein nanoparticles can specifically target mitochondria. This targeting is desirable, since mitochondria are critical in the development of cancer cells. In this study, the discovery of a novel self-assembled metal protein nanoparticle, designated GST-MT-3, is reported, which targets the mitochondria of cancer cells within 30 min in vitro and rapidly accumulates in tumors within 1 h in vivo. The nanoparticles chelate cobalt ions [GST-MT-3(Co2+ )], which induces reactive oxygen species (ROS) production and reduces the mitochondrial membrane potential. These effects lead to antitumor activity in vivo. GST-MT-3(Co2+ ) with covalently conjugated paclitaxel synergistically suppress tumors and prolong survival. Importantly, the effective dosage of paclitaxel is 50-fold lower than that utilized in standard chemotherapy (0.2 vs 10 mg kg-1 ). To the best of the authors' knowledge, GST-MT-3 is the first reported protein nanoparticle that targets mitochondria. It has the potential to be an excellent platform for combination therapies.


Asunto(s)
Nanopartículas/química , Nanomedicina Teranóstica/métodos , Animales , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos/métodos , Femenino , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Metalotioneína 3 , Ratones , Ratones Endogámicos BALB C , Neoplasias/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo
5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(3): 344-350, 2019 Jun 30.
Artículo en Zh | MEDLINE | ID: mdl-31282328

RESUMEN

Objective To explore the clinical characteristics of autoimmune disease with dual seropositive antibodies of leucine-rich glioma inactivated 1(LGI1)and contactin-associated protein 2(Caspr2).Methods The clinical data of seven patients with dual seropositive LGI1 and Caspr2 antibodies who were admitted to the Neurology Department of Peking Union Medical College Hospital from July 2014 to December 2017 were retrospectively analyzed.Results Central,peripheral and autonomic nervous systems were all involved in the seven cases;100%(7/7)presented with insomnia,myokymia,neuropahic pain and hyperhydrosis;71%(5/7)showed memory decline or psychiatric and behavioral symptoms;57%(4/7)had urinary hesitation or constipation;and 43%(3/7)had seizure.Electromyography showed 100%(6/6) of the patients had prolonged afterdischarges following normal M waves and/or abnormal spontaneous firing.Electroencephalography revealed slow waves or basic rhythm slowing in 71%(5/7)of patients.Electrocardiography showed sinus tachycardia,axis deviation,and prolonged QT intervals in 71%(5/7)of patients.One patient died from arrhythmia before immunotherapy.One died from pulmonary infection after immunotherapy.Improvement with immunotherapy was documented in the other five cases.No relapse was noted during the 1-2-year follow-up.Conclusions Autoimmune disease with dual seropositive antibodies of LGI1 and Caspr2 can diffusely affect the central,peripheral,and autonomic nervous systems.The possibility of this disease should be considered in patients with acute and subacute onset of neuropsychiatric symptoms,especially in patients with accompanying insomnia,myokymia,and hyperhydrosis.


Asunto(s)
Autoanticuerpos/sangre , Enfermedades Autoinmunes/inmunología , Proteínas de la Membrana/inmunología , Proteínas del Tejido Nervioso/inmunología , Proteínas/inmunología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Estudios Retrospectivos
6.
Lipids Health Dis ; 17(1): 126, 2018 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-29807528

RESUMEN

BACKGROUND: Inconsistencies have existed in research findings on the association between cardiovascular disease (CVD) and single nucleotide polymorphisms (SNPs) of ADIPOQ, triggering this up-to-date meta-analysis. METHODS: We searched for relevant studies in PubMed, EMBASE, Cochrane Library, CNKI, CBM, VIP, and WanFang databases up to 1st July 2017. We included 19,106 cases and 31,629 controls from 65 published articles in this meta-analysis. STATA 12.0 software was used for all statistical analyses. RESULTS: Our results showed that rs266729 polymorphism was associated with the increased risk of CVD in dominant model or in heterozygote model; rs2241766 polymorphism was associated with the increased risk of CVD in the genetic models (allelic, dominant, recessive, heterozygote, and homozygote). In subgroup analysis, significant associations were found in different subgroups with the three SNPs. Meta-regression and subgroup analysis showed that heterogeneity might be explained by other confounding factors. Sensitivity analysis revealed that the results of our meta-analysis were stable and robust. In addition, the results of trial sequential analysis showed that evidences of our results are sufficient to reach concrete conclusions. CONCLUSIONS: In conclusion, our meta-analysis found significant increased CVD risk is associated with rs266729 and rs2241766, but not associated with rs1501299.


Asunto(s)
Adiponectina/genética , Enfermedades Cardiovasculares/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Enfermedades Cardiovasculares/metabolismo , Estudios de Asociación Genética , Humanos
7.
Physiol Plant ; 156(4): 421-43, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26400148

RESUMEN

Plasma membrane NADPH oxidases are major producers of reactive oxygen species (ROS) in plant cells under normal growth and stress conditions. In the present study the total activity of rice NADPH oxidases and the transcription of OsRbohA, which encodes an Oryza sativa plasma membrane NADPH oxidase, were stimulated by drought. OsRbohA was expressed in all tissues examined throughout development. Its mRNA was upregulated by a number of factors, including heat, drought, salt, oxidative stress and methyl jasmonate treatment. Compared with wild-type (WT), the OsRbohA-knockout mutant osrbohA exhibited upregulated expression of other respiratory burst oxidase homolog genes and multiple abnormal agronomic traits, including reduced biomass, low germination rate and decreased pollen viability and seed fertility. However, OsRbohA-overexpressing transgenic plants showed no differences in these traits compared with WT. Although osrbohA leaves and roots produced more ROS than WT, the mutant had lesser intracellular ROS. In contrast, OsRbohA-overexpressing transgenic plants exhibited higher ROS production at the intracellular level and in tissues. Ablation of OsRbohA impaired the tolerance of plants to various water stresses, whereas its overexpression enhanced the tolerance. In addition, a number of genes related to energy supply, substrate transport, stress response and transcriptional regulation were differentially expressed in osrbohA plants even under normal growth conditions, suggesting that OsRbohA has fundamental and broad functions in rice. These results indicate that OsRbohA-mediated processes are governed by complex signaling pathways that function during the developmental regulation and drought-stress response in rice.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , NADPH Oxidasas/metabolismo , Oryza/enzimología , Transducción de Señal , Acetatos/metabolismo , Membrana Celular/enzimología , Ciclopentanos/metabolismo , Sequías , Germinación , Mutación , NADPH Oxidasas/genética , Oryza/citología , Oryza/genética , Oryza/fisiología , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Hojas de la Planta/citología , Hojas de la Planta/enzimología , Hojas de la Planta/genética , Hojas de la Planta/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Raíces de Plantas/fisiología , Plantas Modificadas Genéticamente , Especies Reactivas de Oxígeno/metabolismo , Plantones/citología , Plantones/enzimología , Plantones/genética , Plantones/fisiología , Cloruro de Sodio/farmacología , Estrés Fisiológico
8.
BMC Public Health ; 16: 296, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-27039079

RESUMEN

BACKGROUND: Metabolic syndrome (MS) comprises a set of conditions that are risk factors for cardiovascular diseases and diabetes. Numerous epidemiological studies on MS have been conducted, but there has not been a systematic analysis of the prevalence of MS in the Chinese population. Therefore, the aim of this study was to estimate the pooled prevalence of MS among subjects in Mainland China. METHODS: We performed a systematic review by searching both English and Chinese literature databases. Random or fixed effects models were used to summarize the prevalence of MS according to statistical tests for heterogeneity. Subgroup, sensitivity, and meta-regression analyses were performed to address heterogeneity. Publication bias was evaluated using Egger's test. RESULTS: Thirty-five papers were included in the meta-analysis, with a total population of 226,653 Chinese subjects. Among subjects aged 15 years and older, the pooled prevalence was 24.5% (95% CI: 22.0-26.9%). By sex, the prevalences were 19.2% (95% CI: 16.9-21.6%) in males and 27.0% (95% CI: 23.5-30.5%) in females. The pooled prevalence of MS increased with age (15-39 years: 13.9%; 40-59 years: 26.4%; and 60 years: 32.4%). Individuals living in urban areas (24.9%, 95% CI: 18.5-31.3%) were more likely to suffer from MS than those living in rural areas (19.2%, 95% CI: 14.8-23.7%). Hypertension was the most prevalent component of MS in males (52.8%), while the most prevalent component of MS for females was central obesity (46.1%). CONCLUSIONS: Our systematic review suggested a high prevalence of MS among subjects in Mainland China, indicating that MS is a serious public health problem. Therefore, more attention should be paid to the prevention and control of MS.


Asunto(s)
Síndrome Metabólico/epidemiología , Distribución por Edad , China/epidemiología , Humanos , Prevalencia , Factores de Riesgo , Distribución por Sexo
9.
Micromachines (Basel) ; 15(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38398963

RESUMEN

MXene has emerged as a highly promising two-dimensional (2D) layered material with inherent advantages as an electrode material, such as a high electrical conductivity and spacious layer distances conducive to efficient ion transport. Despite these merits, the practical implementation faces challenges due to MXene's low theoretical capacitance and issues related to restacking. In order to overcome these limitations, we undertook a strategic approach by integrating Ti3C2Tx MXene with cobalt molybdate (CoMoO4) nanoparticles. The CoMoO4 nanoparticles bring to the table rich redox activity, high theoretical capacitance, and exceptional catalytic properties. Employing a facile hydrothermal method, we synthesized CoMoO4/Ti3C2Tx heterostructures, leveraging urea as a size-controlling agent for the CoMoO4 precursors. This innovative heterostructure design utilizes Ti3C2Tx MXene as a spacer, effectively mitigating excessive agglomeration, while CoMoO4 contributes its enhanced redox reaction capabilities. The resulting CoMoO4/Ti3C2Tx MXene hybrid material exhibited 698 F g-1 at a scan rate of 5 mV s-1, surpassing that of the individual pristine Ti3C2Tx MXene (1.7 F g-1) and CoMoO4 materials (501 F g-1). This integration presents a promising avenue for optimizing MXene-based electrode materials, addressing challenges and unlocking their full potential in various applications.

10.
Microbiol Spectr ; : e0409723, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101823

RESUMEN

Infection control measures to prevent viral and bacterial infection spread are critical to maintaining a healthy environment. Pathogens such as viruses and pyogenic bacteria can cause infectious complications. Viruses such as SARS-CoV-2 are known to spread through the aerosol route and on fomite surfaces, lasting for a prolonged time in the environment. Developing technologies to mitigate the spread of pathogens through airborne routes and on surfaces is critical, especially for patients at high risk for infectious complications. Multifunctional coatings with a broad capacity to bind pathogens that result in inactivation can disrupt infectious spread through aerosol and inanimate surface spread. This study uses C-POLAR, a proprietary cationic, polyamine, organic polymer with a charged, dielectric property coated onto air filtration material and textiles. Using both SARS-CoV-2 live viral particles and bovine coronavirus models, C-POLAR-treated material shows a dramatic 2-log reduction in circulating viral inoculum. This reduction is consistent in a static room model, indicating simple airflow through a static C-POLAR hanging can capture significant airborne particles. Finally, Gram-positive and Gram-negative bacteria are applied to C-POLAR textiles using a viability indicator to demonstrate eradication on fomite surfaces. These data suggest that a cationic polymer surface can capture and eradicate human pathogens, potentially interrupting the infectious spread for a more resilient environment. IMPORTANCE: Infection control is critical for maintaining a healthy home, work, and hospital environment. We test a cationic polymer capable of capturing and eradicating viral and bacterial pathogens by applying the polymer to the air filtration material and textiles. The data suggest that the simple addition of cationic material can result in the improvement of an infectious resilient environment against viral and bacterial pathogens.

11.
J Periodontol ; 94(2): 193-203, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35942553

RESUMEN

BACKGROUND: Severe periodontitis is one of the most prevalent diseases and a global public health problem due to its high incidence and prevalence. However, there are few studies on the burden of periodontitis in different regions of the world. METHODS: We extracted data on the incidence, prevalence, and disability-adjusted life years (DALYs) from the Global Burden of Disease study as severe periodontitis burden measures. We also explored the global burden of severe periodontitis according to 21 world regions and Socio-Demographic Index (SDI) quintiles. The joinpoint model was used to analyze temporal trends of major regions from 1990 to 2019, and the age-period-cohort model was used to estimate age, period, and cohort trends in severe periodontitis. RESULTS: Globally, the age-standardized incidence rate (ASIR), age-standardized prevalence rate (ASPR), and disability-adjusted life years (DALYs) rate increased from 1990 to 2019 (percentage change: 5.77%, 7.78%, and 8.01%, respectively), with average annual percent changes of 0.2%, 0.3%, and 0.3%, respectively. The region with the highest DALY rate was western sub-Saharan Africa with a value of 142.5 (95% uncertainty interval: 56.3, 303.7) per 100,000 in 2019. For the ASIR, ASPR, and DALY, the age effect of severe periodontitis showed an increase followed by a decrease, the period effect showed an upward trend, the cohort effect showed an overall decreasing trend, and the cohort relative risk for incidence for some SDI quintiles showed a slight increase in recent years. CONCLUSIONS: Oral health varies significantly across regions, and it is essential to address inequalities in oral health between countries. Effective measures to prevent severe periodontitis risk factors should also be taken in regions with low SDI.


Asunto(s)
Años de Vida Ajustados por Discapacidad , Carga Global de Enfermedades , Humanos , Incidencia , Prevalencia , Años de Vida Ajustados por Calidad de Vida
12.
Front Med (Lausanne) ; 10: 1154411, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37089613

RESUMEN

Background and study aims: In recent years, cold snare polypectomy (CSP) has been increasingly used for small polyps (<10 mm) instead of hot snare polypectomy (HSP). However, evidence-based research regarding the effectiveness and safety of CSP and HSP are still lacking. Additionally, for 4-10 -mm non-pedunculated polyps, the polyp removal method is still controversial. Therefore, it is clinically significant to conduct pair-wise and network meta-analyses to assess such resection methods. Methods: We searched PubMed, Embase, and the Cochrane library for randomized controlled trials (RCTs). Only studies that involved the resection of polyps <10 mm were included. Outcomes included the complete resection rate, polyp retrieval rate, procedure-related complications, and procedure times. Results: Overall, 23 RCTs (5,352 patients) were identified. In meta-analysis compared CSP versus HSP for polyps <10 mm, CSP showed lower complete resection rate than HSP although with no statistically significant difference [odds ratio (OR): 0.77, 95% confidence interval (CI): 0.56-1.06]. CSP showed a lower risk of major post-polypectomy complications compared to HSP (OR: 0.28, 95% CI: 0.11-0.73). In the network meta-analysis for 4-10 mm non-pedunculated polyps, HSP, and endoscopic mucosal resection (EMR) showed a higher complete resection rate than CSP (OR: 2.7, 95% CI: 1.3-9.2 vs. OR: 2.6, 95% CI: 1.0-10) but a significantly longer time than CSP (WMD: 16.55 s, 95% CI [7.48 s, 25.25 s], p < 0.001), (WMD: 48.00 s, 95% CI [16.54 s, 79.46 s], p = 0.003). Underwater CSP ranked third for complete resection with no complications. Conclusion: For <10 mm polyps, CSP is safer than HSP, especially for patients taking antithrombotic drugs. For 4-10 mm non-pedunculated polyps, HSP, and EMR have higher complete resection rates than CSP. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022315575.

13.
World J Psychiatry ; 13(11): 967-972, 2023 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-38073893

RESUMEN

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive lipid-storage disorder caused by mutations in CYP27A1. Psychiatric manifestations in CTX are rare and nonspecific, and they often lead to considerable diagnostic and treatment delay. CASE SUMMARY: A 33-year-old female patient admitted to the psychiatric ward for presentation of delusions, hallucinations, and behavioral disturbance is reported. The patient presented with cholestasis, cataract, Achilles tendon xanthoma, and cerebellar signs in adulthood and with intellectual disability and learning difficulties in childhood. After the characteristic CTX findings on imaging were obtained, a pathological examination of the Achilles tendon xanthoma was refined. Re-placement therapy was then initiated after the diagnosis was clarified by genetic analysis. During hospitalization in the psychiatric ward, the nonspecific psychiatric manifestations of the patient posed difficulty in diagnosis. After the patient's history of CTX was identified, the patient was diagnosed with organic schizophrenia-like disorder, and psychotic symptoms were controlled by replacement therapy combined with antipsychotic medication. CONCLUSION: Psychiatrists should be aware of CTX, its psychiatric manifestations, and clinical features and avoid misdiagnosis of CTX for timely intervention.

14.
Redox Biol ; 65: 102829, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37527604

RESUMEN

Gut health is important for nutrition absorption, reproduction, and lactation in perinatal and early weaned mammals. Although melatonin functions in maintaining circadian rhythms and preventing obesity, neurodegenerative diseases, and viral infections, its impact on the gut microbiome and its function in mediating gut health through gut microbiota remain largely unexplored. In the present study, the microbiome of rats was monitoring after fecal microbiota transplantation (FMT) and foster care (FC). The results showed that FMT and FC increased intestinal villus height/crypt depth in perinatal rats. Mechanistically, the melatonin-mediated remodeling of gut microbiota inhibited oxidative stress, which led to attenuation of autophagy and inflammation. In addition, FMT and FC encouraged the growth of more beneficial intestinal bacteria, such as Allobaculum, Bifidobacterium, and Faecalibaculum, which produce more short-chain fatty acids to strengthen intestinal anti-oxidation. These findings suggest that melatonin-treated gut microbiota increase the production of SCFAs, which improve gut health by reducing oxidative stress, autophagy and inflammation. The transfer of melatonin-treated gut microbiota may be a new and effective method by which to ameliorate gut health in perinatal and weaned mammals.


Asunto(s)
Microbioma Gastrointestinal , Melatonina , Femenino , Ratas , Animales , Melatonina/farmacología , Trasplante de Microbiota Fecal/métodos , Inflamación , Mamíferos
15.
Langmuir ; 28(44): 15624-8, 2012 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-23066985

RESUMEN

This theoretical study was motivated by recent experiments and theoretical work that had suggested the dependence of the static contact angle on the local wetting at the triple-phase contact line. We revisit this topic because the static contact angle as a local wetting parameter is still not widely understood and clearly known. To further clarify the relationship of the static contact angle with wetting, two approaches are applied to derive a general equation for the static contact angle of a droplet on a composite surface composed of heterogeneous components. A global approach based on the free surface energy of a thermodynamic system containing the droplet and solid surface shows the static contact angle as a function of local surface chemistry and local wetting state at the contact line. A local approach, in which only local forces acting on the contact line are considered, results in the same equation. The fact that the local approach agrees with the global approach further demonstrates the static contact angle as a local wetting parameter. Additionally, the study also suggests that the wetting described by the Wenzel and Cassie equations is also the local wetting of the contact line rather than the global wetting of the droplet.

16.
Langmuir ; 28(6): 3180-6, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22235939

RESUMEN

Prevention of ice accretion and adhesion on surfaces is relevant to many applications, leading to improved operation safety, increased energy efficiency, and cost reduction. Development of passive nonicing coatings is highly desirable, since current antiicing strategies are energy and cost intensive. Superhydrophobicity has been proposed as a lead passive nonicing strategy, yet the exact mechanism of delayed icing on these surfaces is not clearly understood. In this work, we present an in-depth analysis of ice formation dynamics upon water droplet impact on surfaces with different wettabilities. We experimentally demonstrate that ice nucleation under low-humidity conditions can be delayed through control of surface chemistry and texture. Combining infrared (IR) thermometry and high-speed photography, we observe that the reduction of water-surface contact area on superhydrophobic surfaces plays a dual role in delaying nucleation: first by reducing heat transfer and second by reducing the probability of heterogeneous nucleation at the water-substrate interface. This work also includes an analysis (based on classical nucleation theory) to estimate various homogeneous and heterogeneous nucleation rates in icing situations. The key finding is that ice nucleation delay on superhydrophobic surfaces is more prominent at moderate degrees of supercooling, while closer to the homogeneous nucleation temperature, bulk and air-water interface nucleation effects become equally important. The study presented here offers a comprehensive perspective on the efficacy of textured surfaces for nonicing applications.

17.
Org Biomol Chem ; 10(31): 6279-86, 2012 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-22722482

RESUMEN

Three fluorescent probes CdABA', CdABA and ZnABA', which are structural isomers of ZnABA, have been designed with N,N-bis(2-pyridylmethyl) ethylenediamine (BPEA) as chelator and 2-aminobenzamide as fluorophore. These probes can be divided into two groups: CdABA, CdABA' for Cd(2+) and ZnABA, ZnABA' for Zn(2+). Although there is little difference in their chemical structures, the two groups of probes exhibit totally different fluorescence properties for preference of Zn(2+) or Cd(2+). In the group of Zn(2+) probes, ZnABA/ZnABA' distinguish Zn(2+) from Cd(2+) with F(Zn)(2+)-F(Cd)(2+) = 1.87-2.00. Upon interchanging the BPEA and carbamoyl groups on the aromatic ring of the fluorophore, the structures of ZnABA/ZnABA' are converted into CdABA/CdABA'. Interestingly, the metal ions selectivity of CdABA/CdABA' was switched to discriminate Cd(2+) from Zn(2+) with F(Cd)(2+)-F(Zn)(2+) = 2.27-2.36, indicating that a small structural modification could lead to a remarkable change of the metal ion selectivity. (1)H NMR titration and ESI mass experiments demonstrated that these fluorescent probers exhibited different coordination modes for Zn(2+) and Cd(2+). With CdABA' as an example, generally, upon addition of Cd(2+), the fluorescence response possesses PET pathway to display no obvious shift of maximum λ(em) in the absence or presence of Cd(2+). However, an ICT pathway could be employed after adding Zn(2+) into the CdABA' solution, resulting in a distinct red-shift of maximal λ(em).


Asunto(s)
Cadmio/química , Quelantes/química , Colorantes Fluorescentes/química , Indazoles/química , Zinc/química , ortoaminobenzoatos/química , Cristalografía por Rayos X , Etilenodiaminas/química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Espectrometría de Fluorescencia
18.
Front Neurosci ; 16: 814684, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35221904

RESUMEN

BACKGROUND: Traumatic brain injury (TBI) is considered a risk factor for the development of stroke (Hemorrhagic Stroke and Ischemic Stroke). We performed this systemic review and meta-analysis to determine the association of prior TBI with the subsequent diagnosis of stroke. METHODS: We systematically searched PubMed, EMBASE, and the Cochrane Library for cohort studies involving TBI patients who subsequently developed stroke. Study selection, data extraction, and quality assessment were performed by two separate researchers. Data were analyzed with random-effects models, and a secondary analysis stratified by the type of stroke was performed. RESULTS: Of the 741 identified studies, 6 studies were eligible for inclusion, with more than 2,200,000 participants. TBI predicted the occurrence of stroke in the random-effect model, with a relative risk of 2.14 (95% CI 1.97-2.32, P < 0.001). Furthermore, in the analysis of each type of stroke, TBI was associated with the incidence of ischemic stroke (RR 1.351 95% CI 1.212-1.506, P < 0.001), and TBI was associated with an even greater increase in the incidence of hemorrhagic stroke (RR 6.118 95% CI 5.265-7.108, P < 0.001). CONCLUSION: Our meta-analysis showed that TBI was associated with a more than two-fold increase in the risk of stroke. However, owing to the high degree of heterogeneity, decisions should be made on a patient-by-patient basis. The occurrence of TBI is associated with the development of both hemorrhagic and ischemic stroke, and the risk of hemorrhagic stroke is much higher than that of ischemic stroke in TBI patients.

19.
Prim Care Diabetes ; 16(6): 736-744, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36184528

RESUMEN

AIM: To assess the impact of the obesity epidemic on type 2 diabetes (T2D), prediabetes and glycometabolic indices in children and adolescents. METHODS: We searched four electronic databases (PubMed, Embase, Cochrane and Web of Science). Cross-sectional or cohort studies that reported on obesity and the prevalence of T2D or prediabetes in children and adolescents were reviewed. The study design, sample size and clinical outcomes were extracted from each study. The prevalence of T2D and prediabetes from the studies were pooled using meta-analysis methods. RESULTS: Meta-analysis of 228184 participants showed that the prevalence of T2D was 1.3% (95% confidence interval (CI), 0.6-2.1%) in obese subjects, which was 13 times that in normal weight subjects (0.1%, 95% CI, 0.01-0.2%). The prevalence of prediabetes in obese subjects was 3 times that in normal subjects at 17.0% (13.0-22.0%) vs. 6.0% (0.01-11.0%). Moreover, BMI was positively correlated with the prevalence of T2D, prediabetes and glycometabolic indices in obese children and adolescents. CONCLUSION: The pooled results confirm that obesity in children and adolescents leads to statistically significant increases in the prevalence of T2D and prediabetes and in glycometabolic indicator levels.


Asunto(s)
Diabetes Mellitus Tipo 2 , Obesidad Infantil , Estado Prediabético , Adolescente , Niño , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Estado Prediabético/diagnóstico , Estado Prediabético/epidemiología , Glucemia/análisis , Obesidad Infantil/diagnóstico , Obesidad Infantil/epidemiología , Estudios Transversales
20.
Materials (Basel) ; 15(16)2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-36013923

RESUMEN

Thermophysiological comfort is known to play a primary role in maintaining thermal balance, which corresponds to a person's satisfaction with their immediate thermal environment. Among the existing test methods, sweating torsos are one of the best tools to provide a combined measurement of heat and moisture transfer using non-isothermal conditions. This study presents a preliminary numerical model of a single sector sweating torso to predict the thermophysiological comfort properties of fabric systems. The model has been developed using COMSOL Multiphysics, based on the ISO 18640-1 standard test method and a single layer fabric system used in sportswear. A good agreement was observed between the experimental and numeral results over different exposure phases simulated by the torso test (R2 = 0.72 to 0.99). The model enables a systematic investigation of the effect of fabric properties (thickness, porosity, thermal resistance, and evaporative resistance), environmental conditions (relative humidity, air and radiant temperature, and wind speed), and physiological parameters (sweating rate) to gain an enhanced understanding of the thermophysiological comfort properties of the fabric system.

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