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1.
J Comput Chem ; 45(18): 1576-1586, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38516839

RESUMO

Lead-free double perovskites are unique materials for transport and optoelectronic applications that use clean resources to generate energy. Using first-principle computations, this study thoroughly investigates the structural, thermoelectric, and optical attributes of A2TlAgF6 (A = Rb, Cs). Tolerance factor and formation energy estimates are used to verify that these materials exist in the cubic phase. Elastic constants with high melting temperature values are ductile when evaluated for mechanical stability using the Born stability criterion. The optical absorption band is adjusted from 2 to 4 eV via band gaps of 1.88 and 1.99 eV, as indicated by band structures. Analysis of optical properties reveals perfect absorption in the visible spectrum, whole polarization, and low optical loss. Furthermore, thermoelectric properties are assessed at 300, 500, and 700 K in the range of -0.5 to 3 eV for chemical potential (µ). The materials exhibit significant improvements in the Figure of Merit scale due to their elevated electrical conductivity, Seebeck coefficient, and extremely low thermal conductivity values.

2.
J Mol Recognit ; 37(1): e3066, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37916582

RESUMO

Hepatitis C virus infection causes chronic diseases such as cirrhosis and hepatocellular carcinoma. Metabolomics research has been shown to be linked to pathophysiologic pathways in liver illnesses. The aim of this study was to investigate the serum metabolic profile of patients with chronic hepatitis C (CHC) infection and to identify underlying mechanisms as well as potential biomarkers associated with the disease. Nuclear magnetic resonance (NMR) was used to evaluate the sera of 83 patients with CHC virus and 52 healthy control volunteers (NMR). Then, multivariate statistical analysis was used to find distinguishing metabolites between the two groups. Sixteen out of 40 metabolites including include 3-HB, betaine, carnitine, creatinine, fucose, glutamine, glycerol, isopropanol, lysine, mannose, methanol, methionine, ornithine, proline, serine, and valine-were shown to be significantly different between the CHC and normal control (NC) groups (variable importance in projection >1 and p < 0.05). All the metabolic perturbations in this disease are associated with pathways of Glycine, serine, and threonine metabolism, glycerolipid metabolism, arginine and proline metabolism, aminoacyl-tRNA biosynthesis, cysteine and methionine metabolism, alanine, aspartate, and glutamate metabolism. Multivariate statistical analysis constructed using these expressed metabolites showed CHC patients can be discriminated from NCs with high sensitivity (90%) and specificity (99%). The metabolomics approach may expand the diagnostic armamentarium for patients with CHC while contributing to a comprehensive understanding of disease mechanisms.


Assuntos
Hepatite C Crônica , Humanos , Hepatite C Crônica/diagnóstico , Metaboloma , Metionina , Prolina , Serina
3.
Muscle Nerve ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056231

RESUMO

INTRODUCTION/AIMS: Corneal confocal microscopy (CCM) detects small nerve fiber loss and correlates with skin biopsy findings in diabetic neuropathy. In chronic idiopathic axonal polyneuropathy (CIAP) this correlation is unknown. Therefore, we compared CCM and skin biopsy in patients with CIAP to healthy controls, patients with painful diabetic neuropathy (PDN) and diabetics without overt neuropathy (DM). METHODS: Participants with CIAP and suspected small fiber neuropathy (n = 15), PDN (n = 16), DM (n = 15), and healthy controls (n = 16) underwent skin biopsy and CCM testing. Inter-center intraclass correlation coefficients (ICC) were calculated for CCM parameters. RESULTS: Compared with healthy controls, patients with CIAP and PDN had significantly fewer nerve fibers in the skin (IENFD: 5.7 ± 2.3, 3.0 ± 1.8, 3.9 ± 1.5 fibers/mm, all p < .05). Corneal nerve parameters in CIAP (fiber density 23.8 ± 4.9 no./mm2, branch density 16.0 ± 8.8 no./mm2, fiber length 13.1 ± 2.6 mm/mm2) were not different from healthy controls (24.0 ± 6.8 no./mm2, 22.1 ± 9.7 no./mm2, 13.5 ± 3.5 mm/mm2, all p > .05). In patients with PDN, corneal nerve fiber density (17.8 ± 5.7 no./mm2) and fiber length (10.5 ± 2.7 mm/mm2) were reduced compared with healthy controls (p < .05). CCM results did not correlate with IENFD in CIAP patients. Inter-center ICC was 0.77 for fiber density and 0.87 for fiber length. DISCUSSION: In contrast to patients with PDN, corneal nerve parameters were not decreased in patients with CIAP and small nerve fiber damage. Therefore, CCM is not a good biomarker for small nerve fiber loss in CIAP patients.

4.
Pediatr Surg Int ; 40(1): 163, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935193

RESUMO

The aim of this study was to compare the operative parameters and complication rates between the umbilical (UMB) and right upper quadrant (RUQ) skin incisions for Ramstedt's pyloromyotomy for the treatment of infantile hypertrophic pyloric stenosis (IHPS). PubMed, EMBASE, Web of Science and Scopus databases were systematically searched. The studies where any one of the main outcomes of interest, i.e., operative time, wound infection rate, mucosal perforation rate were reported were eligible for inclusion. The statistical analysis was performed using a random-effects model. The methodological quality of the studies was assessed utilizing the Newcastle-Ottawa Scale. Fifteen studies comprising 2964 infants were included. As compared to the UMB group, the RUQ group showed a significantly lower mean operative time (p = 0.0004), wound infection rate (p < 0.0001) and mucosal perforation rate (p = 0.02). Although UMB incision produces an almost undetectable scar, this approach results in significantly more complications. Therefore, the risks and benefits must be weighed and discussed with the caregivers in deciding the surgical approach in patients with IHPS. However, due to a poor methodological quality of nine out of fifteen studies, further studies need to be conducted for an optimal comparison between the two groups.


Assuntos
Estenose Pilórica Hipertrófica , Piloromiotomia , Umbigo , Humanos , Estenose Pilórica Hipertrófica/cirurgia , Piloromiotomia/métodos , Umbigo/cirurgia , Lactente , Complicações Pós-Operatórias/epidemiologia , Infecção da Ferida Cirúrgica/epidemiologia , Duração da Cirurgia , Recém-Nascido
5.
Pediatr Surg Int ; 40(1): 152, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847871

RESUMO

The aim of this study was to analyze the role of thiol/disulfide homeostasis (TDH) parameters as an indicator of oxidative stress in acute appendicitis (AA). PubMed, EMBASE, Web of Science, and Scopus databases were systematically searched. Studies reporting on TDH in AA (both complicated and uncomplicated cases) were included. The comparator group were healthy controls. The TDH domain was compared between the groups using anti-oxidant parameters, namely native thiol and total thiol levels, and native thiol/total thiol ratio; and oxidant parameters, namely disulfide level, disulfide/native thiol ratio, and disulfide/total thiol ratio. The statistical analysis was performed using a random-effects model. The methodological quality of the studies was assessed utilizing the Newcastle-Ottawa scale. Eleven studies with a total of 926 subjects, comprising 457 patients with uncomplicated appendicitis, 147 with complicated appendicitis, and 322 healthy controls were included. Our study demonstrated significantly increased oxidative stress in AA as compared to healthy controls in all TDH parameters and significantly lower total thiol levels in complicated AA as compared to uncomplicated AA. Due to a poor methodological quality in five out of eleven studies, future prospective studies with adequate power are essential to validate these observations and refine the diagnostic approaches to AA.


Assuntos
Apendicite , Biomarcadores , Dissulfetos , Homeostase , Estresse Oxidativo , Compostos de Sulfidrila , Apendicite/sangue , Apendicite/diagnóstico , Humanos , Compostos de Sulfidrila/sangue , Homeostase/fisiologia , Dissulfetos/sangue , Biomarcadores/sangue , Estresse Oxidativo/fisiologia , Doença Aguda
6.
Alzheimers Dement ; 20(2): 1421-1435, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37897797

RESUMO

This editorial summarizes advances from the Clearance of Interstitial Fluid and Cerebrospinal Fluid (CLIC) group, within the Vascular Professional Interest Area (PIA) of the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART). The overarching objectives of the CLIC group are to: (1) understand the age-related physiology changes that underlie impaired clearance of interstitial fluid (ISF) and cerebrospinal fluid (CSF) (CLIC); (2) understand the cellular and molecular mechanisms underlying intramural periarterial drainage (IPAD) in the brain; (3) establish novel diagnostic tests for Alzheimer's disease (AD), cerebral amyloid angiopathy (CAA), retinal amyloid vasculopathy, amyloid-related imaging abnormalities (ARIA) of spontaneous and iatrogenic CAA-related inflammation (CAA-ri), and vasomotion; and (4) establish novel therapies that facilitate IPAD to eliminate amyloid ß (Aß) from the aging brain and retina, to prevent or reduce AD and CAA pathology and ARIA side events associated with AD immunotherapy.


Assuntos
Doença de Alzheimer , Angiopatia Amiloide Cerebral , Transtornos Cerebrovasculares , Humanos , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Líquido Extracelular , Angiopatia Amiloide Cerebral/terapia , Angiopatia Amiloide Cerebral/patologia , Encéfalo/metabolismo , Transtornos Cerebrovasculares/complicações
7.
BMC Oral Health ; 24(1): 81, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38221633

RESUMO

BACKGROUND: In the classification of bruxism patients based on electroencephalogram (EEG), feature extraction is essential. The method of using multi-channel EEG fusing electrocardiogram (ECG) and Electromyography (EMG) signal features has been proved to have good performance in bruxism classification, but the classification performance based on single channel EEG signal is still understudied. We investigate the efficacy of single EEG channel in bruxism classification. METHODS: We have extracted time-domain, frequency-domain, and nonlinear features from single EEG channel to classify bruxism. Five common bipolar EEG recordings from 2 bruxism patients and 4 healthy controls during REM sleep were analyzed. The time domain (mean, standard deviation, root mean squared value), frequency domain (absolute, relative and ratios power spectral density (PSD)), and non-linear features (sample entropy) of different EEG frequency bands were analyzed from five EEG channels of each participant. Fine tree algorithm was trained and tested for classifying sleep bruxism with healthy controls using five-fold cross-validation. RESULTS: Our results demonstrate that the C4P4 EEG channel was most effective for classification of sleep bruxism that yielded 95.59% sensitivity, 98.44% specificity, 97.84% accuracy, and 94.20% positive predictive value (PPV). CONCLUSIONS: Our results illustrate the feasibility of sleep bruxism classification using single EEG channel and provides an experimental foundation for the development of a future portable automatic sleep bruxism detection system.


Assuntos
Bruxismo do Sono , Fases do Sono , Humanos , Bruxismo do Sono/diagnóstico , Valor Preditivo dos Testes , Eletroencefalografia/métodos , Algoritmos
8.
J Indian Assoc Pediatr Surg ; 29(1): 23-27, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38405247

RESUMO

Aim: The aim is to study intrahepatic biliary architecture in patients following Kasai's portoenterostomy for extrahepatic biliary atresia using magnetic resonance cholangiopancreatography (MRCP). Materials and Methods: It is a prospective observational study in a cohort of patients who have survived with a complete jaundice-free period for at least 1 year. MRCP was done to look for various intrahepatic architectural changes during their last visit. Findings were correlated with liver functions and growth and development. Results: Twenty-one patients were included in the study. The male-to-female sex ratio was 1.6:1, the median age at surgery was 75 days (18-140 days), and the median age at magnetic resonance imaging (MRI) was 4 years (18 months-18 years). More than 2 years of follow-up was in seven patients. Left lobe hypertrophy was observed in six patients, right lobe hypertrophy was in three patients, intrahepatic biliary tract dilatation was in five patients, and altered signal intensity between intrahepatic ducts was seen in five patients. In addition, hypointense foci in the spleen were seen in one patient. Twelve children had normal weight for their age, ten children had the normal height for their age, and gamma-glutamyl transferase was elevated in all children. Only four children had a history of fever and jaundice. Conclusions: The patients who survive after successful surgical intervention have near-normal liver gross architecture as on MRI/MRCP. Occasional findings of dilatation and lobar atrophy/hypertrophy are possible, especially in those with a history of cholangitis. The survivors also have acceptable growth parameters and normal liver functions.

9.
Angew Chem Int Ed Engl ; : e202411960, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39166719

RESUMO

Porous materials perform molecular sorting, separation and transformation by interaction between their framework structures and the substrates. Proteins also interact with molecules to effect chemical transformations, but rely on the precise sequence of the amino acid building units along a common polypeptide backbone to maximise their performance. Design strategies that positionally order sidechains over a defined porous framework to diversify the internal surface chemistry would enhance control of substrate processing. Here we show that different sidechains can be ordered over a metal-organic framework through recognition of their distinct chemistries during synthesis. The sidechains are recognised because each one forces the common building unit that defines the backbone of the framework into a different conformation in order to form the extended structure. The resulting sidechain ordering affords hexane isomer separation performance superior to that of the same framework decorated only with sidechains of a single kind. The separated molecules adopt distinct arrangements within the resulting modified pore geometry, reflecting their strongly differentiated environments precisely created by the ordered sidechains. The development of frameworks that recognise  and  order multiple sidechain functionality by conformational control offers tailoring of the internal surfaces within families of porous materials to direct interactions at the molecular level.

10.
Neurobiol Dis ; 176: 105963, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521781

RESUMO

Excessive daytime sleepiness is a recognized non-motor symptom that adversely impacts the quality of life of people with Parkinson's disease (PD), yet effective treatment options remain limited. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective treatment for PD motor signs. Reliable daytime sleep-wake classification using local field potentials (LFPs) recorded from DBS leads implanted in STN can inform the development of closed-loop DBS approaches for prompt detection and disruption of sleep-related neural oscillations. We performed STN DBS lead recordings in three nonhuman primates rendered parkinsonian by administrating neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Reference sleep-wake states were determined on a second-by-second basis by video monitoring of eyes (eyes-open, wake and eyes-closed, sleep). The spectral power in delta (1-4 Hz), theta (4-8 Hz), low-beta (8-20 Hz), high-beta (20-35 Hz), gamma (35-90 Hz), and high-frequency (200-400 Hz) bands were extracted from each wake and sleep epochs for training (70% data) and testing (30% data) a support vector machines classifier for each subject independently. The spectral features yielded reasonable daytime sleep-wake classification (sensitivity: 90.68 ± 1.28; specificity: 88.16 ± 1.08; accuracy: 89.42 ± 0.68; positive predictive value; 88.70 ± 0.89, n = 3). Our findings support the plausibility of monitoring daytime sleep-wake states using DBS lead recordings. These results could have future clinical implications in informing the development of closed-loop DBS approaches for automatic detection and disruption of sleep-related neural oscillations in people with PD to promote wakefulness.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Animais , Estimulação Encefálica Profunda/métodos , Qualidade de Vida , Núcleo Subtalâmico/fisiologia , Sono/fisiologia , Doença de Parkinson/terapia
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