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1.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38829214

RESUMO

A versatile graphene epitaxy (GrapE) furnace has been designed and fabricated for the growth of epitaxial graphene (EG) on silicon carbide (SiC) in diverse growth environments ranging from high vacuum to atmospheric argon pressure. Radio-frequency induction enables heating capabilities up to 2000 °C, with controlled heating ramp rates achievable up to 200 °C/s. The details of critical design aspects and temperature characteristics of the GrapE system are discussed. The GrapE system, being automated, has enabled the growth of high-quality EG monolayers and turbostratic EG on SiC using diverse methodologies, such as confinement-controlled sublimation (CCS), open configuration, polymer-assisted CCS, and rapid thermal annealing. This showcases the versatility of the GrapE system in EG growth. Comprehensive characterizations involving atomic force microscopy, Raman spectroscopy, and low-energy electron diffraction techniques were employed to validate the quality of the produced EG.

2.
Neurotoxicol Teratol ; 100: 107292, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37666366

RESUMO

AIM: To describe the neurodevelopmental phenotype of older children and adults with a diagnosis of Fetal Valproate Spectrum Disorder (FVSD). METHODS: In this cross-sectional study, 90 caregivers were recruited and completed a series of questionnaires regarding the neurodevelopmental outcomes of 146 individuals aged 7-37 years (M = 18.1), including individuals with a formal diagnosis of FVSD (n = 99), individuals exposed to Valproate but without an FVSD diagnosis (n = 24), and individuals not exposed to Valproate (N = 23). The mean dose of valproate exposure for individuals with an FVSD diagnosis was 1470 mg/day. RESULTS: Individuals with a diagnosis of FVSD showed significantly higher levels of moderate (43.4%) and severe (14.4%) cognitive impairment than other groups (p = 0.003), high levels of required formal educational support (77.6%), and poorer academic competence than individuals not exposed to Valproate (p = 0.001). Overall psychosocial problems (p = 0.02), internalising problems (p = 0.05) and attention problems (p = 0.001), but not externalising problems, were elevated in individuals with a diagnosis of FVSD. Rates of neurodevelopmental disorders, particularly autistic spectrum disorders (62.9%) and sensory problems (80.6%) are particularly central to the FVSD phenotype. There was no evidence of a statistical dose-dependent effect, possibly due to the high mean dose of exposure having a uniformly negative impact across the sample. Individuals with FVSD had required a significant number of health and child development services. INTERPRETATION: Children and young adults with a diagnosis of FVSD are at an increased risk of a range of altered neurodevelopmental outcomes, highlighting the need for a multidisciplinary approach to clinical management across the lifespan.


Assuntos
Epilepsia , Ácido Valproico , Adulto Jovem , Humanos , Criança , Adolescente , Ácido Valproico/efeitos adversos , Anticonvulsivantes , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Estudos Transversais
3.
Front Hum Neurosci ; 17: 1125906, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250695

RESUMO

Introduction: Despite known health disparities in cognitive aging, a comprehensive rationale for the increased burden in older minoritized populations including non-Latino Black and Latino adults has yet to be elucidated. While most work has focused on person-specific risk, studies are increasingly assessing neighborhood-level risk. We evaluated multiple aspects of the environmental milieu that may be critical when considering vulnerability to adverse health outcomes. Methods: We investigated associations between a Census-tract derived Social Vulnerability Index (SVI) and level of and change in cognitive and motor functioning in 780 older adults (590 non-Latino Black adults, ∼73 years old at baseline; 190 Latinos, ∼70 years old baseline). Total SVI scores (higher = greater neighborhood-level vulnerability) were combined with annual evaluations of cognitive and motor functioning (follow-up ranged from 2 to 18 years). Demographically-adjusted mixed linear regression models tested for associations between SVI and cognitive and motor outcomes in analyses stratified by ethno-racial group. Results: For non-Latino Black participants, higher SVI scores were associated with lower levels of global cognitive and motor functioning-specifically, episodic memory, motor dexterity and gait-as well as longitudinal change in visuospatial abilities and hand strength. For Latinos, higher SVI scores were associated with lower levels of global motor functioning only-specifically, motor dexterity; there were no significant associations between SVI and change in motor functioning. Discussion: Neighborhood-level social vulnerability is associated with cognitive and motor functioning in non-Latino Black and Latino older adults, although associations appear to contribute to level more so than longitudinal change.

5.
Ann R Coll Surg Engl ; 104(2): 148-152, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35100843

RESUMO

INTRODUCTION: This is the first study aimed at objectively quantifying the benefit of virtual education using WhatsApp-based discussion groups. METHODS: A prospective, non-randomised interventional study was undertaken in the Department of General Surgery, at a tertiary care centre in Kolkata, India, with 200 undergraduate students over a period of 5 days each for 2 weeks, with the first week acting as a control arm. A WhatsApp group was created consisting of 197 eligible undergraduates, faculty members and the authors of this study. Each day, three questions were posted on this group. The second week involved an hour-long WhatsApp-based discussion between the participants and the faculty. Responses were recorded and compared for improvements between the two weeks. Participant feedback was collected and analysed. RESULTS: Statistically significant improvements were observed in the study group compared with the control group in rates of one in three, two in three and three in three correct responses (p=0.01649, 0.01146 and 0.00946, respectively). A total of 68 (51.92%) feedback respondents were satisfied with the programme. Convenience of use was the principal reason behind satisfaction in 79 respondents (60.31%), whereas 62 participants (47.33%) reported lack of hands-on training as a major drawback. CONCLUSIONS: WhatsApp was found to be a satisfactory supplement to traditional medical teaching. It can be implemented to fill lapses in medical education, especially in light of the COVID-19 pandemic, which has caused great disruption to traditional teaching methods. Research is needed to assess the feasibility of incorporating it into the curriculum.


Assuntos
Instrução por Computador , Educação de Graduação em Medicina , Cirurgia Geral/educação , Aplicativos Móveis , Atitude do Pessoal de Saúde , Avaliação Educacional , Humanos , Índia , Estudos Prospectivos , Estudantes de Medicina
6.
Acute Med ; 21(4): 205-206, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36809453

RESUMO

Overuse of corticosteroids is an important problem not only in asthma but also the management of other airways diseases including bronchiectasis and COPD and results in associated risks of serious side effects and irreversible harm. We report a pilot using an in-reach solution to review patients, optimise their care and facilitate early discharge. We discharged >20% of our patients immediately, which is potentially a significant reduction in hospital bed use and, most importantly, through this approach we were able to establish early diagnosis and reduce inappropriate oral corticosteroid use.


Assuntos
Corticosteroides , Asma , Humanos , Corticosteroides/efeitos adversos , Progressão da Doença , Alta do Paciente , Equipe de Assistência ao Paciente
7.
Ann R Coll Surg Engl ; 104(2): 148-152, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34821522

RESUMO

INTRODUCTION: This is the first study aimed at objectively quantifying the benefit of virtual education using WhatsApp-based discussion groups. METHODS: A prospective, non-randomised interventional study was undertaken in the Department of General Surgery, at a tertiary care centre in Kolkata, India, with 200 undergraduate students over a period of 5 days each for 2 weeks, with the first week acting as a control arm. A WhatsApp group was created consisting of 197 eligible undergraduates, faculty members and the authors of this study. Each day, three questions were posted on this group. The second week involved an hour-long WhatsApp-based discussion between the participants and the faculty. Responses were recorded and compared for improvements between the two weeks. Participant feedback was collected and analysed. RESULTS: Statistically significant improvements were observed in the study group compared with the control group in rates of one in three, two in three and three in three correct responses (p=0.01649, 0.01146 and 0.00946, respectively). A total of 68 (51.92%) feedback respondents were satisfied with the programme. Convenience of use was the principal reason behind satisfaction in 79 respondents (60.31%), whereas 62 participants (47.33%) reported lack of hands-on training as a major drawback. CONCLUSIONS: WhatsApp was found to be a satisfactory supplement to traditional medical teaching. It can be implemented to fill lapses in medical education, especially in light of the COVID-19 pandemic, which has caused great disruption to traditional teaching methods. Research is needed to assess the feasibility of incorporating it into the curriculum.


Assuntos
COVID-19 , Educação de Graduação em Medicina , COVID-19/epidemiologia , COVID-19/prevenção & controle , Currículo , Educação de Graduação em Medicina/métodos , Humanos , Pandemias/prevenção & controle , Estudos Prospectivos
8.
J Neuromuscul Dis ; 8(6): 899-926, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511509

RESUMO

There are growing numbers of adults with Duchenne Muscular Dystrophy living well into their fourth decade. These patients have complex medical needs that to date have not been addressed in the International standards of care. We sought to create a consensus based standard of care through a series of multi-disciplinary workshops with specialists from a wide range of clinical areas: Neurology, Cardiology, Respiratory Medicine, Gastroenterology, Endocrinology, Palliative Care Medicine, Rehabilitation, Renal, Anaesthetics and Clinical Psychology. Detailed reports of evidence reviewed and the consensus building process were produced following each workshop and condensed into this final document which was approved by all members of the Adult North Star Network including service users. The aim of this document is to provide a framework to improve clinical services and multi-disciplinary care for adults living with Duchenne Muscular Dystrophy.


Assuntos
Consenso , Distrofia Muscular de Duchenne/terapia , Padrão de Cuidado , Adulto , Humanos , Inquéritos e Questionários
9.
Resour Conserv Recycl ; 164: 105140, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32921915

RESUMO

The Trans-Atlantic Research and Development Interchange on Sustainability Workshop (TARDIS) is a meeting on scientific topics related to sustainability. The 2019 workshop theme was "On the Role of Uncertainty in Managing the Earth for Global Sustainability." This paper presents the perspectives on this topic derived from talks and discussions at the 2019 TARDIS workshop. There are four kinds of uncertainties encountered in sustainability ranging from clear enough futures to true surprises. The current state-of-the-art in assessing and mitigating these uncertainties is discussed.

11.
Appl Radiat Isot ; 148: 49-59, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30921617

RESUMO

Ore minerals in dolomites and Graphite Mica Schist (GMS) were studied by synchrotron radiation micro-computed tomography (SR-µCT) and optical microscopy. High resolution µCT images of ore minerals were obtained at Imaging Beamline (BL-4), Indus-2 synchrotron radiation source for the comprehensive volume characterization of minerals. Optical microscopy was used for mineral identification, mineral/rock characterization and quantification of ore mineral assemblages was also confirmed by XRD. 3D images from SR-µCT have shown spatial distribution of major minerals and crystals of different minerals in the volume of samples. The results obtained shows that the GMS and dolomitic hosted rocks mined from region near Udaipur, Rajasthan contains sulfide mineral phases. SR-µCT facilitates visualization of the association of the various metallic minerals with the host rock. The presence of economically important metallic minerals galena, sphalerite and pyrite found in the samples through SR-µCT has implications on exploration and processing of ores.

12.
Food Funct ; 10(1): 33-37, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30632580

RESUMO

Lactulose, a non-digestible oligosaccharide and functional food, promotes Bifidobacteria growth. Here we show that lactulose, beyond its prebiotic action, may have direct immunomodulatory effects as well. In synergy with CpG-ODN, a bacterial DNA mimetic, lactulose enhances basolateral concentrations of IFN-γ, IL-10, and galectin-9 in the co-culture model of epithelial and immune cells.


Assuntos
Comunicação Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Lactulose/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Oligodesoxirribonucleotídeos/farmacologia , Sinergismo Farmacológico , Células Epiteliais/citologia , Células Epiteliais/imunologia , Células HT29 , Humanos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Lactulose/química , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Oligodesoxirribonucleotídeos/química
13.
Materials (Basel) ; 12(1)2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30591643

RESUMO

Ca12Al14O33 (C12A7 or Mayenite) is a material whose caged clathrate structure and occluded anionic species leads to significant functionality. The creation of occluded anionic vacancies leads to the injection of localized electrons at the center of the cage, converting the wide band gap insulator to a semi- or metallic conducting material. The conversion to the electride historically requires the synthesis of oxy-C12A7, consolidation, and then reduction to introduce anionic vacancies. This report develops and characterizes an electride formation procedure from three starting points: unconsolidated oxy-C12A7, heterogenous solid-state reactants (CaCO3 and Al2O3), and homogenous non-carbonaceous polymer assisted sol-gel reactants. Electride-C12A7 formation is observed in a vacuum furnace where the reactants are in direct contact with a carbon source. Process time and temperature-dependent structural characterization provides insight into the source of high temperature C12A7 stability, the mechanism of anionic vacancy formation, and the magnitude of ultimate conductivity that cannot be explained by current reduction theories. A new theory is presented where mixed O- and C-occupied cages lead to high temperature stability, oxidation of C species creates anionic vacancies, and an equilibrium between the reducing power of the electride-C12A7 and of the C species leads to the ultimate conductivity achieved by the process. This represents a shift in understanding of the carbonaceous reduction process and the first report of high purity electride-C12A7 formation from heterogenous solid-state reactants and homogenous non-carbonaceous polymer assisted sol-gel reactants.

14.
Ann R Coll Surg Engl ; : 1-7, 2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30112955

RESUMO

Over the past three decades, management of blunt splenic trauma has changed radically. Use of improved diagnostic techniques and proper understanding of disease pathology has led to nonoperative management being chosen as the standard of care in patients who are haemodynamically stable. This review was undertaken to assess available literature regarding changing trends of management of blunt splenic trauma, and to identify the existing lacunae in nonoperative management. The PubMed database was searched for studies published between January 1987 and August 2017, using the keywords 'blunt splenic trauma' and 'nonoperative management'. One hundred and fifty-three articles were reviewed, of which 82 free full texts and free abstracts were used in the current review. There is clear evidence in published literature of the greater success of nonoperative over operative management in patients who are haemodynamically stable and the increasing utility of adjunctive therapies like angiography with embolisation. However, the review revealed a lack of universal guidelines for patient selection criteria and diagnostic and grading procedures needed for nonoperative management. Indications for splenic artery embolisation, the current role of splenectomy and spleen-preserving surgeries, together with the place of minimal access surgery in blunt splenic trauma remain grey areas. Moreover, parameters affecting the outcomes of nonoperative management and its failure and management need to be defined. This shows a need for future studies focused on these shortcomings with the ultimate aim being the formulation and implementation of universally accepted guidelines for safe and efficient management of blunt splenic trauma.

15.
Pancreatology ; 18(5): 513-515, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29784598

RESUMO

BACKGROUND/OBJECTIVES: Respiratory dysfunction and/or failure from acute lung injury (ALI) are common in acute pancreatitis (AP), but assessment of ALI in experimental AP has lacked standardisation. METHODS: A range of experimental AP models induced in C57BL/6 mice with corresponding controls (n = 6/group). Full double lung or right lung specimens were taken for histopathological assessment and slides analysed by a pre-set pipeline using Aperio Scanner (Leica), ImageJ software and CellProfiler software. Findings were compared to other routinely assessed parameters. RESULTS: Overall histopathological changes were similar between both lungs. Mean lung field occupancy was significantly different between moderate and severe CER-AP (21.9% v 27.5%, p < 0.05) and corresponded with lung MPO and local injury severity parameters and was mirrored for all models tested. CONCLUSION: We have developed a novel, simple method for assessment of ALI to improve measurement of systemic organ injury in experimental AP and contribute to preclinical drug development.

17.
Trop Anim Health Prod ; 49(7): 1517-1522, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28752213

RESUMO

Porcine rotavirus type A (RVA) is a major cause of neonatal piglet mortality in India. The effect of the disease on haemogram and serum biochemical profile is not well established in piglets. Accordingly, we assessed the haemogram and serum biochemical profile in the neonatal piglet diarrhoea with RVA infection (n = 17). The diagnosis of RVA was confirmed using RNA-polyacrylamide gel electrophoresis (RNA-PAGE), commercially available enzyme-linked immunosorbent assay (ELISA) kit and reverse transcription-polymerase chain reaction (RT-PCR). Non-infected healthy piglets (n = 6) served as control. The concentrations of total protein, albumin, alanine amino transaminase (ALT), aspartate amino transaminase (AST), blood urea nitrogen (BUN) and creatinine in serum were measured by spectrophotometric method. Haemogram was done in the blood using sodium ethylenediaminetetraacetic acid (Na2 EDTA) as anticoagulant. The mean values of total protein, albumin and globulin concentrations were significantly (P < 0.001) decreased and concentrations of ALT, AST, BUN and creatinine were significantly increased (P < 0.001) in the RVA-infected piglets. Haemogram showed marked haemoconcentration (P < 0.001), leukopenia (P < 0.01) and neutropenia (P < 0.01) in the presence of RVA infection than healthy piglets. The results indicated a possible extra-intestinal spread of RVA in piglets during neonatal diarrhoea. The finding might be helpful to clinicians and while treating such type of clinical cases, incorporation of organ protective drugs will be helpful for better response in the treatment schedule.


Assuntos
Contagem de Células Sanguíneas/veterinária , Diarreia/veterinária , Infecções por Rotavirus/veterinária , Rotavirus/fisiologia , Doenças dos Suínos/sangue , Animais , Animais Recém-Nascidos , Diarreia/sangue , Diarreia/virologia , Feminino , Índia , Masculino , Infecções por Rotavirus/sangue , Infecções por Rotavirus/virologia , Sus scrofa , Suínos , Doenças dos Suínos/virologia
18.
Neurotoxicology ; 62: 100-110, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28587808

RESUMO

In this study, we examined the effects of alcohol exposure during gastrulation on zebrafish embryos, specifically focusing on excitatory synaptic activity associated with neurons (Mauthner cells) that are born during gastrulation. Furthermore, we determined whether co-treatment of alcohol and retinoic acid (RA) could prevent the effects of alcohol exposure during gastrulation. We exposed zebrafish embryos to ethanol (150mM), RA (1nM), or a combination of RA (1nM) plus ethanol (150mM) for 5.5h from 5.25h post fertilization (hpf) to 10.75 hpf (gastrulation). Ethanol treatment resulted in altered hatching rates, survivability and body lengths. Immunohistochemical analysis of Mauthner cells (M-cells) suggested that ethanol treatment resulted in smaller M-cell bodies and thinner axons, while electrophysiological recordings of AMPA miniature excitatory postsynaptic currents (mEPSCs) associated with M-cells showed that ethanol treated animals had a significantly reduced mEPSC frequency. Other mEPSC parameters such as amplitude, rise times and decay kinetics were not altered by exposure to alcohol. Locomotor studies showed that ethanol treatment resulted in altered C-bend escape responses. For instance, the C-bends of alcohol-treated fish were larger than control embryos. Thus, ethanol treatment during gastrulation altered a range of features in embryonic zebrafish. Importantly, co-treatment with RA prevented all of the effects of ethanol including survivability, body length, M-cell morphology, AMPA mEPSC frequency and escape response movements. Together these findings show that ethanol exposure during the brief period of gastrulation has a significant effect on neuronal morphology and activity, and that this can be prevented with RA co-treatment.


Assuntos
Encéfalo/citologia , Etanol/toxicidade , Gastrulação/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Tretinoína/farmacologia , Fatores Etários , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Depressores do Sistema Nervoso Central/toxicidade , Edema/induzido quimicamente , Embrião não Mamífero , Reação de Fuga/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Masculino , Movimento/efeitos dos fármacos , Neurotransmissores/farmacologia , Peixe-Zebra , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia
19.
Clin Exp Immunol ; 187(3): 490-506, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27936497

RESUMO

Coeliac disease (CD) is an autoimmune enteropathy triggered by gluten and characterized by a strong T helper type 1 (Th1)/Th17 immune response in the small intestine. Regulatory T cells (Treg ) are CD4+ CD25++ forkhead box protein 3 (FoxP3+ ) cells that regulate the immune response. Conversely to its counterpart, FoxP3 full length (FL), the alternatively spliced isoform FoxP3 Δ2, cannot properly down-regulate the Th17-driven immune response. As the active state of CD has been associated with impairments in Treg cell function, we aimed at determining whether imbalances between FoxP3 isoforms may be associated with the disease. Intestinal biopsies from patients with active CD showed increased expression of FOXP3 Δ2 isoform over FL, while both isoforms were expressed similarly in non-coeliac control subjects (HC). Conversely to what we saw in the intestine, peripheral blood mononuclear cells (PBMC) from HC subjects did not show the same balance between isoforms. We therefore hypothesized that the intestinal microenvironment may play a role in modulating alternative splicing. The proinflammatory intestinal microenvironment of active patients has been reported to be enriched in butyrate-producing bacteria, while high concentrations of lactate have been shown to characterize the preclinical stage of the disease. We show that the combination of interferon (IFN)-γ and butyrate triggers the balance between FoxP3 isoforms in HC subjects, while the same does not occur in CD patients. Furthermore, we report that lactate increases both isoforms in CD patients. Collectively, these findings highlight the importance of the ratio between FoxP3 isoforms in CD and, for the first time, associate the alternative splicing process mechanistically with microbial-derived metabolites.


Assuntos
Doença Celíaca/metabolismo , Citocinas/metabolismo , Epigênese Genética/genética , Fatores de Transcrição Forkhead/metabolismo , Inflamação/metabolismo , Interferon gama/metabolismo , Microbiota/fisiologia , Adolescente , Adulto , Idoso , Antígenos CD4/metabolismo , Doença Celíaca/genética , Regulação para Baixo/genética , Feminino , Humanos , Inflamação/genética , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/metabolismo , Linfócitos T Reguladores/metabolismo , Células Th17/metabolismo , Adulto Jovem
20.
Phys Rev Lett ; 117(23): 235701, 2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27982606

RESUMO

The structural properties of LaCu_{6-x}Au_{x} are studied using neutron diffraction, x-ray diffraction, and heat capacity measurements. The continuous orthorhombic-monoclinic structural phase transition in LaCu_{6} is suppressed linearly with Au substitution until a complete suppression of the structural phase transition occurs at the critical composition x_{c}=0.3. Heat capacity measurements at low temperatures indicate residual structural instability at x_{c}. The instability is ferroelastic in nature, with density functional theory calculations showing negligible coupling to electronic states near the Fermi level. The data and calculations presented here are consistent with the zero temperature termination of a continuous structural phase transition suggesting that the LaCu_{6-x}Au_{x} series hosts an elastic quantum critical point.

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