Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 191
Filtrar
1.
Environ Monit Assess ; 195(3): 425, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36826723

RESUMO

Coastal upland forests are facing widespread mortality as sea-level rise accelerates and precipitation and storm regimes change. The loss of coastal forests has significant implications for the coastal carbon cycle; yet, predicting mortality likelihood is difficult due to our limited understanding of disturbance impacts on coastal forests. The manipulative, ecosystem-scale Terrestrial Ecosystem Manipulation to Probe the Effects of Storm Treatments (TEMPEST) experiment addresses the potential for freshwater and estuarine-water disturbance events to alter tree function, species composition, and ecosystem processes in a deciduous coastal forest in MD, USA. The experiment uses a large-unit (2000 m2), un-replicated experimental design, with three 50 m × 40 m plots serving as control, freshwater, and estuarine-water treatments. Transient saturation (5 h) of the entire soil rooting zone (0-30 cm) across a 2000 m2 coastal forest was attained by delivering 300 m3 of water through a spatially distributed irrigation network at a rate just above the soil infiltration rate. Our water delivery approach also elevated the water table (typically ~ 2 m belowground) and achieved extensive, low-level inundation (~ 8 cm standing water). A TEMPEST simulation approximated a 15-cm rainfall event and based on historic records, was of comparable intensity to a 10-year storm for the area. This characterization was supported by showing that Hurricane Ida's (~ 5 cm rainfall) hydrologic impacts were shorter (40% lower duration) and less expansive (80% less coverage) than those generated through experimental manipulation. Future work will apply TEMPEST treatments to evaluate coastal forest resilience to changing hydrologic disturbance regimes and identify conditions that initiate ecosystem state transitions.


Assuntos
Ecossistema , Solo , Monitoramento Ambiental , Florestas , Água Doce
2.
RSC Adv ; 12(50): 32684-32692, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36425708

RESUMO

External (in air) PIGE methodology has been optimized for rapid quantification of fluorine, sodium, and phosphorus in fluorapatite waste immobilization matrices for Molten Salt Reactor (MSR). The present methodology addresses the issue of distinguishing hydroxyapatite and fluorapatite phases through XRD patterns. Fluctuations in proton beam current have been monitored by prompt γ-ray from nitrogen (2312 keV) through 14N(p,p'γ)14N nuclear reaction and have successfully been applied as a new method of current normalization, for the first time, in external PIGE method with lower Compton background and negligible spectral interference. The proposed method was also compared with the earlier method of current normalization using 165 keV (181T(p,p'γ)181Ta) from the Tantalum window used for obtaining "in air" beam. For the fluctuation of beam current within 5-10 nA, nitrogen from air can be used as an effective current normalizer. Moreover, the uncertainty (within ±3%) was also improved in the present method of current normalization. Fluorine can be estimated from trace to major concentrations using 197 keV (19F(p,p'γ)19F) γ-ray with highest sensitivity as compared to other prompt γ-rays (110 keV and 1236 keV). The matrix effect in PIGE was also eliminated by diluting the sample in cellulose. The method was validated using the synthetic samples (Ca10(PO4)6F2, Na2Eu2Ca6(PO4)6F2, Na1.5Eu1.5Ca7(PO4)6F2, Na1Eu1Ca8(PO4)6F2, Na0.5Eu0.5Ca9(PO4)6F2, and Sr10(PO4)6F2). The results were found to be satisfactory and in good agreement with stoichiometric amounts. Elements such as Na, P, and Ca were determined in the fluorapatite samples using PIGE and EDXRF, respectively, as a part of chemical quality control. Moreover, in external PIGE, 1266 keV γ-ray (31P(p,p'γ)31P) provides more accurate P concentrations in the samples.

3.
J Laryngol Otol ; 136(6): 479-485, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34588011

RESUMO

OBJECTIVE: This study aimed to formulate a scoring system based on high-resolution computed tomography scans to predict ease of electrode insertion during cochlear implantation via posterior tympanotomy in paediatric patients. METHOD: A scoring system Cochlear Implantation Radiological Assessment Score (CIRAS) was formulated based on six parameters. This score was correlated with intra-operative findings, and receiver operating characteristic analysis was performed to determine the optimal cut-off score to predict difficulty of surgery and to establish the inherent validity of the scoring system by area under curve. RESULTS: Receiver operating characteristic analysis showed that optimal cut-off score was 8 (93.1 per cent specificity and 56.52 per cent sensitivity), and area under the curve was 0.828. Patients with CIRAS of more than 8 had significantly higher time for surgery (p < 0.05). CONCLUSION: CIRAS is an easy to administer tool by utilising classical axial and coronal sections, without any numerical measures. Pre-operative assessment by this score gives a good idea of intra-operative challenges.


Assuntos
Implante Coclear , Implantes Cocleares , Radiologia , Criança , Cóclea/diagnóstico por imagem , Cóclea/cirurgia , Implante Coclear/métodos , Eletrodos Implantados , Humanos , Ventilação da Orelha Média , Tomografia Computadorizada por Raios X
4.
J Laryngol Otol ; 135(1): 39-44, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33487180

RESUMO

OBJECTIVE: To compare endoscopic epitympanic exploration with conventional canal wall up (cortical) mastoidectomy for mucosal chronic otitis media in terms of post-operative outcomes. METHODS: Seventy-six patients diagnosed with chronic otitis media (mucosal variety) were randomly assigned to two treatment groups: endoscopic epitympanic exploration and conventional canal wall up (cortical) mastoidectomy. The groups were compared in terms of: post-operative anatomical outcomes (graft uptake), middle-ear physiological outcomes (post-operative tympanometry), audiological outcomes (air-bone gap), surgical time, post-operative pain, vertigo, and long-term complications such as retraction pocket and re-perforation. RESULTS: There was a statistically significant difference between the groups in terms of mean air-bone gap at 12 months, surgical time, and median post-operative pain measured at 6 hours (p < 0.05). No statistically significant differences were noted in terms of: graft uptake at 1, 3 and 6 months, mean air-bone gap at 3 and 6 months, tympanometry at 3, 6 and 12 months, vertigo at 1 week, or long-term complications. CONCLUSION: Endoscopic epitympanic exploration resulted in significantly better long-term audiological outcomes, shorter operating time and less pain compared with conventional canal wall up (cortical) mastoidectomy.


Assuntos
Endoscopia , Mastoidectomia , Otite Média/patologia , Otite Média/cirurgia , Adulto , Doença Crônica , Endoscopia/métodos , Feminino , Humanos , Masculino , Mucosa/patologia , Membrana Timpânica
5.
Sci Rep ; 11(1): 180, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420179

RESUMO

Nearly a fourth of all enzymatic activities is attributable to oxidoreductases, and the redox reactions supported by this vast catalytic repertoire sustain cellular metabolism. In many biological processes, reduction depends on hydride transfer from either reduced nicotinamide adenine dinucleotide (NADH) or its phosphorylated derivative (NADPH). Despite longstanding efforts to regenerate NADPH by various methods and harness it to support chemoenzymatic synthesis strategies, the lack of product purity has been a major deterrent. Here, we demonstrate that a nanostructured heterolayer Ni-Cu2O-Cu cathode formed by a photoelectrochemical process has unexpected efficiency in direct electrochemical regeneration of NADPH from NADP+. Remarkably, two-thirds of NADP+ was converted to NADPH with no measurable production of the inactive (NADP)2 dimer and at the lowest reported overpotential [- 0.75 V versus Ag/AgCl (3 M NaCl) reference]. Sputtering of nickel on the copper-oxide electrode nucleated an unexpected surface morphology that was critical for high product selectivity. Our results should motivate design of integrated electrolyzer platforms that deploy this heterogeneous catalyst for direct electrochemical regeneration of NADH/NADPH, which is central to design of next-generation biofuel fermentation strategies, biological solar converters, energy-storage devices, and artificial photosynthesis.

7.
J Laryngol Otol ; 134(8): 727-731, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32830635

RESUMO

OBJECTIVE: The aim of this study was to assess change in temperature, audiometric outcomes and post-operative complications following exposure to different light sources during endoscopic ear surgery. METHOD: A total of 64 patients diagnosed with chronic otitis media with central perforation and pure conductive hearing loss underwent endoscopic type 1 tympanoplasty. The patients were randomised into two groups based on the light source used: xenon or light-emitting diode. Temperature was measured using a K type thermocouple at the promontory and round window niche. Mean temperature change with respect to operating time, mean audiometric change, incidence of vomiting in the first 24 hours, vertigo and tinnitus at the end of the first week were observed. RESULTS: Mean temperature change showed a statistically significant difference with increasing length of operating time with the xenon light source and when the two light sources were compared for a particular time interval. Mean audiometric change showed statistically significant deterioration at higher frequencies (4, 6 and 8 kHz) with the xenon light source but only at 8 kHz for the light emitting diode source. When the mean audiometric change was compared between light sources for a particular frequency, statistical significance was found at 4, 6 and 8 kHz. Post-operative complications were vomiting, vertigo and tinnitus (p-values of 0.042, 0.099 and 0.147, respectively, between two groups). CONCLUSION: Light emitting diodes are associated with less significant middle-ear temperature rises and audiometric changes at higher frequencies when compared to xenon light sources. Hence, xenon should be replaced with cooler light sources.


Assuntos
Endoscopia/métodos , Otite Média/cirurgia , Procedimentos Cirúrgicos Otológicos/efeitos adversos , Adulto , Audiometria/estatística & dados numéricos , Estudos de Casos e Controles , Doença Crônica , Orelha Média/patologia , Feminino , Perda Auditiva Condutiva/etiologia , Humanos , Masculino , Duração da Cirurgia , Otite Média/complicações , Procedimentos Cirúrgicos Otológicos/tendências , Complicações Pós-Operatórias/epidemiologia , Janela da Cóclea , Temperatura , Zumbido/epidemiologia , Timpanoplastia/métodos , Vertigem/epidemiologia , Vômito/epidemiologia , Xenônio
8.
AJNR Am J Neuroradiol ; 41(3): 449-455, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32079601

RESUMO

BACKGROUND AND PURPOSE: Graph theory uses structural similarity to analyze cortical structural connectivity. We used a voxel-based definition of cortical covariance networks to quantify and assess the relationship of network characteristics to cognition in a cohort of patients with relapsing-remitting MS with and without cognitive impairment. MATERIALS AND METHODS: We compared subject-specific structural gray matter network properties of 18 healthy controls, 25 patients with MS with cognitive impairment, and 55 patients with MS without cognitive impairment. Network parameters were compared, and predictive value for cognition was assessed, adjusting for confounders (sex, education, gray matter volume, network size and degree, and T1 and T2 lesion load). Backward stepwise multivariable regression quantified predictive factors for 5 neurocognitive domain test scores. RESULTS: Greater path length (r = -0.28, P < .0057) and lower normalized path length (r = 0.36, P < .0004) demonstrated a correlation with average cognition when comparing healthy controls with patients with MS. Similarly, MS with cognitive impairment demonstrated a correlation between lower normalized path length (r = 0.40, P < .001) and reduced average cognition. Increased normalized path length was associated with better performance for processing (P < .001), learning (P < .001), and executive domain function (P = .0235), while reduced path length was associated with better executive (P = .0031) and visual domains. Normalized path length improved prediction for processing (R 2 = 43.6%, G2 = 20.9; P < .0001) and learning (R 2 = 40.4%, G2 = 26.1; P < .0001) over a null model comprising confounders. Similarly, higher normalized path length improved prediction of average z scores (G2 = 21.3; P < .0001) and, combined with WM volume, explained 52% of average cognition variance. CONCLUSIONS: Patients with MS and cognitive impairment demonstrate more random network features and reduced global efficiency, impacting multiple cognitive domains. A model of normalized path length with normal-appearing white matter volume improved average cognitive z score prediction, explaining 52% of variance.


Assuntos
Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Adulto , Disfunção Cognitiva/patologia , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/patologia , Substância Branca/patologia
9.
Eur Arch Paediatr Dent ; 21(4): 427, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32016816

RESUMO

In the original publication of the article the fifth author's name "A. Littlewood" was submitted as "A. Littewood" which was left unnoticed in the later stages. The correct name is as published in this erratum.

10.
Eur Arch Paediatr Dent ; 21(4): 407-426, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31858481

RESUMO

PURPOSE: To determine in which clinical situations it is indicated or contra-indicated to prescribe cone beam computed tomography (CBCT) for paediatric patients. METHODS: Systematic review of in vivo paediatric research studies of diagnostic efficacy using CBCT, with supplementary searches for guideline documents on CBCT and for systematic reviews permitting inclusion of ex vivo and adult studies. RESULTS: After screening, 190 publications were included, mostly case studies. No systematic reviews were found of in vivo paediatric research. Fourteen studies of diagnostic efficacy were identified. The supplementary searches found 18 guideline documents relevant to the review and 26 systematic reviews. The diagnostic efficacy evidence on CBCT was diverse and often of limited quality. There was ex vivo evidence for diagnostic accuracy being greater using CBCT than radiographs for root fractures. The multiplanar capabilities of CBCT are advantageous when localising dental structures for surgical planning. Patient movement during scanning is more common in children which could reduce diagnostic efficacy. CONCLUSIONS: No strong recommendations on CBCT are possible, except that it should not be used as a primary diagnostic tool for caries. Guidelines on use of CBCT in the paediatric age group should be developed cautiously, taking into account the greater radiation risk and the higher economic costs compared with radiography. CBCT should only be used when adequate conventional radiographic examination has not answered the question for which imaging was required. Clinical research in paediatric patients is required at the higher levels of diagnostic efficacy of CBCT.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Odontopediatria , Criança , Humanos
11.
J Laryngol Otol ; 133(12): 1033-1037, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31718728

RESUMO

OBJECTIVE: To assess the effect of tranexamic acid on intra-operative bleeding and surgical field visualisation. METHODS: Fifty patients undergoing various endoscopic ear surgical procedures, including endoscopic tympanoplasty, endoscopic atticotomy or mastoidectomy, endoscopic ossiculoplasty, and endoscopic stapedotomy, were randomly assigned to: a study group that received tranexamic acid or a control group which received normal saline. The intra-operative bleeding and operative field visualisation was graded using the Das and Mitra endoscopic ear surgery bleeding and field visibility score, which was separately analysed for the external auditory canal and the middle ear. RESULTS: The Das and Mitra score was better (p < 0.05) in the group that received tranexamic acid as a haemostat when working in the external auditory canal; with respect to the middle ear, no statistically significant difference was found between the two agents. Mean values for mean arterial pressure, heart rate and surgical time were comparable in both groups, with no statistically significant differences. CONCLUSION: Tranexamic acid appears to be an effective haemostat in endoscopic ear surgery, thus improving surgical field visualisation, especially during manipulation of the external auditory canal soft tissues.


Assuntos
Antifibrinolíticos/uso terapêutico , Meato Acústico Externo/cirurgia , Endoscopia/métodos , Procedimentos Cirúrgicos Otológicos/métodos , Ácido Tranexâmico/uso terapêutico , Adolescente , Adulto , Pontos de Referência Anatômicos/cirurgia , Perda Sanguínea Cirúrgica/prevenção & controle , Método Duplo-Cego , Meato Acústico Externo/anatomia & histologia , Feminino , Hemostasia Cirúrgica/métodos , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
J Crohns Colitis ; 13(9): 1111-1120, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30768123

RESUMO

BACKGROUND & AIMS: Vedolizumab is an anti-a4b7 monoclonal antibody that is licensed for the treatment of moderate to severe Crohn's disease and ulcerative colitis. The aims of this study were to establish the real-world effectiveness and safety of vedolizumab for the treatment of inflammatory bowel disease. METHODS: This was a retrospective study involving seven NHS health boards in Scotland between June 2015 and November 2017. Inclusion criteria included: a diagnosis of ulcerative colitis or Crohn's disease with objective evidence of active inflammation at baseline (Harvey-Bradshaw Index[HBI] ≥5/Partial Mayo ≥2 plus C-reactive protein [CRP] >5 mg/L or faecal calprotectin ≥250 µg/g or inflammation on endoscopy/magnetic resonance imaging [MRI]); completion of induction; and at least one clinical follow-up by 12 months. Kaplan-Meier survival analysis was used to establish 12-month cumulative rates of clinical remission, mucosal healing, and deep remission [clinical remission plus mucosal healing]. Rates of serious adverse events were described quantitatively. RESULTS: Our cohort consisted of 180 patients with ulcerative colitis and 260 with Crohn's disease. Combined median follow-up was 52 weeks (interquartile range [IQR] 26-52 weeks). In ulcerative colitis, 12-month cumulative rates of clinical remission, mucosal healing, and deep remission were 57.4%, 47.3%, and 38.5%, respectively. In Crohn's disease, 12-month cumulative rates of clinical remission, mucosal healing, and deep remission were 58.4%, 38.9%, and 28.3% respectively. The serious adverse event rate was 15.6 per 100 patient-years of follow-up. CONCLUSIONS: Vedolizumab is a safe and effective treatment for achieving both clinical remission and mucosal healing in ulcerative colitis and Crohn's disease.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fármacos Gastrointestinais/uso terapêutico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Proteína C-Reativa/análise , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Fezes/química , Feminino , Fármacos Gastrointestinais/efeitos adversos , Humanos , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Estimativa de Kaplan-Meier , Complexo Antígeno L1 Leucocitário/análise , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Escócia , Resultado do Tratamento
13.
Int Endod J ; 51 Suppl 3: e238-e249, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28881396

RESUMO

AIM: To identify guidelines on endodontics which make recommendations relating to post-root canal treatment radiological review imaging, to make an objective assessment of their quality using the AGREE tool and to examine the evidence cited in support of their recommendations. METHODOLOGY: The primary sources to identify published guidelines were MEDLINE (Ovid® ) and EMBASE. The search aim was to identify guidelines pertaining to the post-root canal treatment follow-up recommendations published from 1946 with the final search date being 26 June 2016. The primary search was supplemented by searching Internet search engines and several websites that might have guidelines. The guidelines obtained from the search end-result were assessed for quality and scientific evidence using the AGREE II instrument. Similarities and differences in the recommendations were identified. RESULTS: Thirty guidelines were identified, seven of which met the inclusion criteria. Two guidelines used and clearly described the methods for obtaining scientific evidence from which the recommendations were set. The recommendations varied, particularly as regards the timing of the first review radiograph. Some guidelines lacked supporting evidence. CONCLUSIONS: The recommendations for post-root canal treatment radiographic follow-up varied amongst the identified guidelines. However, the methodology for obtaining the scientific evidence was poorly described in most of the guidelines. Guideline development groups should use the AGREE II instrument as a guide to produce higher quality guidelines.


Assuntos
Cavidade Pulpar/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Tratamento do Canal Radicular , Humanos
14.
Sci Rep ; 7(1): 3354, 2017 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-28611374

RESUMO

Prolonged treatment of tuberculosis (TB) often leads to poor compliance, default and relapse, converting primary TB patients into category II TB (Cat IITB) cases, many of whom may convert to multi-drug resistant TB (MDR-TB). We have evaluated the immunotherapeutic potential of Mycobacterium indicus pranii (MIP) as an adjunct to Anti-Tubercular Treatment (ATT) in Cat II pulmonary TB (PTB) patients in a prospective, randomized, double blind, placebo controlled, multicentric clinical trial. 890 sputum smear positive Cat II PTB patients were randomized to receive either six intra-dermal injections (2 + 4) of heat-killed MIP at a dose of 5 × 108 bacilli or placebo once in 2 weeks for 2 months. Sputum smear and culture examinations were performed at different time points. MIP was safe with no adverse effects. While sputum smear conversion did not show any statistically significant difference, significantly higher number of patients (67.1%) in the MIP group achieved sputum culture conversion at fourth week compared to the placebo (57%) group (p = 0.0002), suggesting a role of MIP in clearance of the bacilli. Since live bacteria are the major contributors for sustained incidence of TB, the potential of MIP in clearance of the bacilli has far reaching implications in controlling the spread of the disease.


Assuntos
Vacinas contra a Tuberculose/efeitos adversos , Tuberculose Pulmonar/terapia , Vacinação/métodos , Vacinas de Produtos Inativados/efeitos adversos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium/imunologia , Vacinas contra a Tuberculose/uso terapêutico , Vacinação/efeitos adversos , Vacinas de Produtos Inativados/uso terapêutico
15.
J Phys Condens Matter ; 28(7): 075001, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26809017

RESUMO

We present the effect of different stacking orders on carrier transport properties of multi-layer black phosphorous. We consider three different stacking orders AAA, ABA and ACA, with increasing number of layers (from 2 to 6 layers). We employ a hierarchical approach in density functional theory (DFT), with structural simulations performed with generalized gradient approximation (GGA) and the bandstructure, carrier effective masses and optical properties evaluated with the meta-generalized gradient approximation (MGGA). The carrier transmission in the various black phosphorous sheets was carried out with the non-equilibrium green's function (NEGF) approach. The results show that ACA stacking has the highest electron and hole transmission probabilities. The results show tunability for a wide range of band-gaps, carrier effective masses and transmission with a great promise for lattice engineering (stacking order and layers) in black phosphorous.

16.
Neuroscience ; 305: 36-48, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26208845

RESUMO

Identifying novel biomarkers of resilience or vulnerability to stress could provide valuable information for the prevention and treatment of stress-related psychiatric disorders. To investigate the utility of blood microRNAs as biomarkers of resilience or vulnerability to stress, microRNAs were assessed before and after 7days of chronic social defeat in rats. Additionally, microRNA profiles of two important stress-regulatory brain regions, the medial prefrontal cortex (mPFC) and basolateral amygdala (BLA), were assessed. Rats that displayed vulnerability to subsequent chronic stress exhibited reductions in circulating miR-24-2-5p, miR-27a-3p, miR-30e-5p, miR-3590-3p, miR-362-3p, and miR-532-5p levels. In contrast, rats that became resilient to stress displayed reduced levels of miR-139-5p, miR-28-3p, miR-326-3p, and miR-99b-5p compared to controls. In the mPFC, miR-126a-3p and miR-708-5p levels were higher in vulnerability compared to resilient rats. In the BLA, 77 microRNAs were significantly altered by stress but none were significantly different between resilient and vulnerable animals. These results provide proof-of-principle that assessment of circulating microRNAs is useful in identifying individuals who are vulnerable to the effects of future stress or individuals who have become resilient to the effects of stress. Furthermore, these data suggest that microRNAs in the mPFC but not in the BLA are regulators of resilience/vulnerability to stress.


Assuntos
Tonsila do Cerebelo/metabolismo , MicroRNAs/metabolismo , Córtex Pré-Frontal/metabolismo , Recuperação de Função Fisiológica/fisiologia , Estresse Psicológico/metabolismo , Estresse Psicológico/patologia , Análise de Variância , Animais , Biomarcadores/metabolismo , Masculino , MicroRNAs/genética , Análise em Microsséries , RNA Mensageiro/metabolismo , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Tempo de Reação/fisiologia , Predomínio Social , Fatores de Tempo
17.
Water Environ Res ; 86(6): 524-31, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25109198

RESUMO

This study describes the potential use of steel-making slag as an arsenic-removal medium. Systematic analysis of slag material revealed a composition of oxides of calcium, iron, silicon, and phosphorous. Under the experimental conditions of this study, the equilibrium time was shown to be 2 hours, and the removal capacity to be 99%, with an adsorbent loading capacity of 1.25g/l. The adsorption kinetics were shown to follow a pseudo-second-order rate equation, and the adsorption isotherm closely followed both the Langmuir and Freundlich isothermic models. Variations in solution pH levels demonstrated that with a decrease in the initial solution pH, the adsorption capacity decreases. This is attributed to the leaching of silica and phosphate from the slag to the solution, which imparted a competing effect for adsorption sites. However, with an alkaline pH, such leaching was reduced, and due to formation of calcium carbonate from the leached calcium from the slag material, the arsenic removal efficiency increased as it was co-precipitated with calcium carbonate.


Assuntos
Arsênio/química , Resíduos Industriais/análise , Aço/química , Poluentes Químicos da Água/química , Adsorção , Cinética , Microscopia Eletrônica de Varredura , Água/química
18.
J Perinatol ; 34(8): 640-1, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25073495

RESUMO

We describe a newborn infant with massive congenital hydrocephalus, presenting with hypomagnesemia secondary to magnesium losses through cerebrospinal fluid (CSF) aspirations. Hypomagnesemia due to CSF losses has not been described in pediatric literature.


Assuntos
Derivações do Líquido Cefalorraquidiano/efeitos adversos , Hidrocefalia/sangue , Hidrocefalia/terapia , Magnésio/sangue , Papiloma do Plexo Corióideo/patologia , Humanos , Hidrocefalia/patologia , Recém-Nascido , Magnésio/líquido cefalorraquidiano , Masculino , Papiloma do Plexo Corióideo/complicações , Papiloma do Plexo Corióideo/cirurgia
19.
Neuroscience ; 264: 88-98, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-23370319

RESUMO

Chronic exposure to stress is associated with a number of psychiatric disorders, but little is known about the epigenetic mechanisms that underlie the stress response or resilience to chronic stress. We investigated histone acetylation in seven different brain regions of rats exposed to chronic social defeat stress: the dorsal hippocampus (dHPC), ventral hippocampus (vHPC), medial prefrontal cortex (mPFC), basolateral amygdala (BLA), locus coeruleus (LC), paraventricular thalamus (PVT), and dorsal raphe (DR) nucleus. This stress paradigm was unique in that it allowed rats to display resilience in the form of an active coping mechanism. We found that there was an increase in acetylation of H3K9/14 (H3K9/14ac) and bulk acetylation of H4K5,8,12,16 (H4K5,8,12,16ac) in the DR nucleus of rats that were less resilient. Less resilient rats also displayed increased levels of H3K18 acetylation (H3K18ac) in the mPFC when compared to non-stressed controls. In the vHPC, there was an increase in H3K18ac and H4K12 (H4K12ac) in rats that were less resilient when compared to non-stressed control rats. In addition, there was a decrease in levels of H4K8 acetylation (H4K8ac) in both resilient and non-resilient rats as compared to controls. We assessed expression of histone modifying enzymes in the vHPC and the mPFC using quantitative real-time polymerase chain reaction (PCR) and found changes in expression of a number of targets. These included changes in Sirt1 and Sirt2 in the vHPC and changes in Kat5 in the mPFC. Overall, these results suggest that changes in histone acetylation and expression of histone modifying enzymes in these regions correlate with the behavioral response to stress in socially defeated rats.


Assuntos
Hipocampo/metabolismo , Histona Acetiltransferases/metabolismo , Histonas/metabolismo , Córtex Pré-Frontal/metabolismo , Núcleos da Rafe/metabolismo , Estresse Psicológico/enzimologia , Acetilação , Animais , Hipocampo/enzimologia , Histona Acetiltransferases/genética , Masculino , Córtex Pré-Frontal/enzimologia , Núcleos da Rafe/enzimologia , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/genética
20.
Physiol Behav ; 130: 182-90, 2014 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-24140988

RESUMO

Maladaptation to stress is associated with psychopathology. However, our understanding of the underlying neural circuitry involved in adaptations to stress is limited. Previous work from our lab indicated the paraventricular hypothalamic neuropeptides orexins/hypocretins regulate behavioral and neuroendocrine responses to stress. To further elucidate the role of orexins in adaptation to stress, we employed optogenetic techniques to specifically examine the effects of orexin cell activation on behavior in the social interaction test and in the home cage as well as orexin receptor 1 internalization and ERK phosphorylation in brain regions receiving orexin inputs. In the social interaction test, optogenetic stimulation of orexin neurons decreased time spent in the interaction zone while increasing the frequency of entries into the interaction zone. In addition, optogenetic stimulation of orexin neurons increased the total distance traveled in the social interaction arena but had no effect on their home cage behavior. Together, these results suggest that orexin release increases anxiety in the social interaction test while increasing the salience of novel but not familiar environmental stimuli. Consistent with activation of orexin neurons, optogenetic stimulation increased orexin receptor1 internalization and ERK phosphorylation in the paraventricular thalamus (PVT) and locus coeruleus (LC), two regions heavily innervated by orexin neurons. Together these results show for the first time that elevation of orexin activity, possibly in the PVT and LC, is associated with increased anxiety, activity, and arousal in a context-specific manner.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Nível de Alerta/fisiologia , Encéfalo/fisiopatologia , Comportamento Exploratório/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neurônios/fisiologia , Neuropeptídeos/metabolismo , Animais , Meio Ambiente , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Locus Cerúleo/fisiopatologia , Masculino , Núcleos da Linha Média do Tálamo/fisiopatologia , Atividade Motora/fisiologia , Testes Neuropsicológicos , Optogenética , Receptores de Orexina/metabolismo , Orexinas , Fosforilação , Córtex Pré-Frontal/fisiopatologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos Sprague-Dawley , Comportamento Social
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...