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In this report, the precise alignment of catalyst free InAs nanowires (NWs) on pre-patterned Au microelectrodes by dielectrophoresis (DEP) technique for gas sensing applications is presented. The catalyst free InAs NWs have been grown on Si (111) substrate by molecular beam epitaxy (MBE) technique. The effect of dispersing solvents, electrode geometries and gaps, magnitude, frequency and duration of applied voltage etc, has been studied for aligning the InAs NWs by DEP technique. Current-voltage (I-V) measurements on the aligned NWs show linear behavior at room temperature (300 K), which changes to nonlinear at lower temperatures and higher voltages. The nonlinearity at lower temperatures and higher voltages is well explained by a space charge limited current contribution, which further gives a quantitative estimation of free charge carriers and trap density. The DEP aligned NWs exhibit good sensing response upon exposure to 10 ppm NO2 gas.
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BACKGROUND AND PURPOSE: The objective of our study was to identify neurological factors associated with poor outcome in adult patients with fulminant bacterial meningitis. METHODS: This was a retrospective review of consecutive adult patients with fulminant bacterial meningitis, defined as meningitis causing coma within 24-48 h of hospitalization, at Mayo Clinic Rochester between January 2000 and November 2010. Functional status was assessed at discharge and upon last follow-up using the modified Rankin scale (mRS). The primary end-point was death or new major disability (increase of >2 on the mRS) at last follow-up. RESULTS: Thirty-nine patients were identified. Encephalopathy (44%), coma (28%), focal seizures (3%) or a combination of these (26%) were present on admission. The most common pathogen was Streptococcus pneumoniae (57%). All patients were treated with broad spectrum antibiotics and 51% received steroids. Serious systemic complications were seen in 23 patients. Sixteen patients (41%) died during hospitalization. Median mRS at hospital discharge for surviving patients was 3; four patients had new major disability with a mean follow-up of 11 months. Predictors of death or new major disability included lower Glasgow Coma Scale score at nadir [P = 0.002; age- and sex-adjusted odds ratio (OR) 0.46, 95% confidence interval (CI) 0.28-0.48], longer duration of symptoms before hospitalization (P = 0.045; adjusted OR 2.34, 95% CI 1.02-5.37), abnormal head imaging at presentation (P = 0.008; adjusted OR 9.40, 95% CI 1.78-49.6) and use of intracranial pressure monitoring (P = 0.010, adjusted OR 51.0, 95% CI 2.51-1036). CONCLUSION: Many adult patients who survive hospitalization are able to regain their pre-morbid level of function. Aggressive management of bacterial meningitis is justified even in comatose adult patients.
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Meningites Bacterianas/diagnóstico , Meningites Bacterianas/mortalidade , Meningites Bacterianas/terapia , Resultado do Tratamento , Adulto , Idoso , Antibacterianos/uso terapêutico , Feminino , Escala de Coma de Glasgow , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Meningites Bacterianas/líquido cefalorraquidiano , Pessoa de Meia-Idade , Neuroimagem , Estudos RetrospectivosRESUMO
BACKGROUND AND PURPOSE: There are few clinical studies on the attempted treatments and outcomes in patients with Susac syndrome (SS) (retinocochleocerebral vasculopathy). METHODS: A retrospective review was performed of all patients presenting with SS at the Mayo Clinic in Rochester, Minnesota, USA (1 January 1998-1 October 2011). RESULTS: There were 29 cases of SS (24 women, mean age at presentation, 35 years; range, 19-65; full triad of brain, eye, and ear involvement, n = 16; mean follow-up time, 29 months). Thirty CSF analyses were performed in 27 cases (mean protein 130 mg/dl, range 35-268; mean cell count 14, range 1-86). MRI of the brain showed corpus callosal involvement (79%), T2-weighted hyperintensities (93%), and gadolinium enhancement (50%). Average lowest modified Rankin Scale score was 2.5 (median 2, range 0-5). Most patients (93%) received immunosuppressive treatment, with a mean time to treatment of 2 months following symptomatic onset. Treatments included intravenous methylprednisolone or dexamethasone (n = 23), oral corticosteroids (n = 24), plasma exchange (PLEX) (n = 9), intravenous immunoglobulin (IVIg) (n = 15), cyclophosphamide (n = 6), mycophenolate mofetil (n = 5), azathioprine (n = 2), and rituximab (n = 1). Most patients also received an antiplatelet agent (n = 21). Improvement or stabilization was noted in eight of 11 cases treated with IVIg in the acute period (three experienced at least partial deterioration) and eight of nine cases of PLEX treatment (one lost to follow up). CONCLUSIONS: Susac syndrome may be severe, disabling, and protracted in some patients. PLEX may be an adjunct or alternative therapy for patients who do not experience symptomatic improvement following steroid treatment.
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Síndrome de Susac/diagnóstico , Síndrome de Susac/terapia , Adulto , Idoso , Corpo Caloso/patologia , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Imunossupressores/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Troca Plasmática/métodos , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Extraction of the weak electrical activity of the "His Bundle" (HB) by noninvasive methods has not been very successful in the past. The study reassesses the use of signal averaged magnetocardiography (SAMCG), overcoming some of the limitations in earlier studies including in the signal averaging methodology. METHODS: SAMCG on healthy subjects (14 male and 1 female) were performed using R-peak as the fiducial point in all cases and also using QRS-onset as the fiducial point in select cases. RESULTS: A conspicuous feature (H) with a magnitude up to 200 femto Tesla (fT) attributed to the HB activity was observed in the PR segment at several spatial positions on the thorax, with onset at 35-50 ms before the QRS-onset (V) in 15 out of 18 trials constituting 83% of cases studied. The QRS-onset as the fiducial point resolved the feature better compared to the conventionally used R-peak, especially in trials exhibiting spread in heart rate (HR). This is attributed to the fluctuations in Q(on) RD (the time interval between QRS-onset and R-peak) compared to the temporal stability of the H-V duration. conclusions: SAMCG reveals a well-resolved H feature. The double hump morphology of the feature extended at least up to a frequency of 150 Hz. The importance of the choice of QRS-onset as the fiducial point is unequivocally demonstrated, illustrated by measurements on subjects exhibiting considerable heart rate variability. The latter has a general validity and should be applicable to SAECG as well.
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Fascículo Atrioventricular/fisiologia , Sistema de Condução Cardíaco/fisiologia , Magnetocardiografia/métodos , Processamento de Sinais Assistido por Computador , Adulto , Estudos de Coortes , Eletrocardiografia/métodos , Feminino , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos TestesRESUMO
Despite being widely investigated for their memristive behavior, ferroelectrics are barely studied as channel materials in field-effect transistor (FET) configurations. In this work, we use multilayer α-In2Se3 to realize a ferroelectric channel semiconductor FET, i.e., FeS-FET, whose gate-triggered and polarization-induced resistive switching is then exploited to mimic an artificial synapse. The FeS-FET exhibits key signatures of a synapse such as excitatory and inhibitory postsynaptic current, potentiation/depression, and paired pulsed facilitation. Multiple stable conductance states obtained by tuning the device are then used as synaptic weights to demonstrate pattern recognition by invoking a hidden layer perceptron model. Detailed artificial neural network (ANN) simulations are performed on binary scale MNIST data digits, invoking 784 input (28 × 28 pixels) and 10 output neurons which are used in the training of 42 000 MNIST data digits. By updating the synaptic weights with conductance weight values on 18 000 digits, we achieved a successful recognition rate of 93% on the testing data. Introduction of 0.10 variance of noise pixels results in an accuracy of more than 70% showing the strong fault-tolerant nature of the conductance states. These synaptic functionalities, learning rules, and device to system-level simulation results based on α-In2Se3 could facilitate the development of more complex neuromorphic hardware systems based on FeS-FETs.
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Accessibility of adequate safe and fresh water for human consumption is one of the most significant issues throughout the world and extensive research is being undertaken to resolve it. Nanotechnology is now an outstanding medium for water treatment and remediation from microorganisms and organic dyes, as compared to conventional treatment methods. For this task graphitic carbon nitride (g-C3N4) is a potential nanomaterial for environmental remediation, but its photogenerated charge carrier recombination rate restricts its use in practical applications. Hence, in the current study, we used a simple one-step calcination method to synthesize various ratios of ZnO/g-C3N4 binary nanocomposites. The band gap of g-C3N4 is 2.70 eV, but it is shifted to 2.60 eV by the 0.75 : 1 ZnO/g-C3N4 binary nanocomposite. Moreover, phase structure, morphology, thermal stability, oxidation state, elemental analysis, and surface area were evaluated using XRD, SEM, TEM, TGA, XPS, and BET analysis. The optimal ZnO loading content was determined and the mechanism of enhanced photocatalytic activity was studied in detail. The photocatalytic efficiency of the best catalyst was employed for the degradation of textile effluent followed by phytotoxicity evaluation using methylene blue (MB), and rhodamine B (RhB) as a model substrate was tested. Furthermore, the textile effluent treatment analysis discovered that the 75 mg concentration of 0.75 : 1 ZnO/g-C3N4 catalyst degraded up to 80% within 120 min and significantly reduced the concentrations of different physico-chemical parameters of textile effluents. These treated effluents have no phytotoxic effects on fenugreek plants, according to a pot study. It was found that the mesoporous 0.75 : 1 ZnO/g-C3N4 catalyst can be used as an effective and low-cost technique for the degradation of azo dyes in textile wastewaters.
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INTRODUCTION AND OBJECTIVE: To characterize enamel defects in patients with methylmalonic acidemia (MMA) and cobalamin (cbl) metabolic disorders and to examine salivary methylmalonate levels in MMA. SUBJECTS AND METHODS: Teeth from patients (n = 32) were evaluated for enamel defects and compared with age- and gender-matched controls (n = 55). Complementation class (mut, cblA, cblB and cblC) and serum methylmalonate levels were examined. Primary teeth from two patients were examined by light and scanning electron microscopy and salivary methylmalonate levels from two patients were analyzed. RESULTS: Enamel defects were significantly more prevalent per tooth in the affected group than the control group, across complementation types (P < 0.0001). The mut MMA subgroup had a significantly higher prevalence per individual of severe enamel defects than controls (P = 0.021), and those with enamel defects exhibited higher serum methylmalonate levels than those without (P = 0.017). Salivary methylmalonate levels were extremely elevated and were significantly higher than controls (P = 0.002). Primary teeth were free of enamel defects except for two cblC patients who exhibited severe enamel hypoplasia. One primary tooth from a cblC patient manifested markedly altered crystal microstructure. CONCLUSION: Enamel anomalies represent a phenotypic manifestation of MMA and cbl metabolic disorders. These findings suggest an association between enamel developmental pathology and disordered metabolism.
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Esmalte Dentário/anormalidades , Erros Inatos do Metabolismo/complicações , Ácido Metilmalônico/metabolismo , Anormalidades Dentárias/metabolismo , Vitamina B 12/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Criança , Esmalte Dentário/ultraestrutura , Dentição Permanente , Feminino , Teste de Complementação Genética , Humanos , Masculino , Análise por Pareamento , Erros Inatos do Metabolismo/classificação , Erros Inatos do Metabolismo/metabolismo , Valores de Referência , Saliva/metabolismo , Estatísticas não Paramétricas , Anormalidades Dentárias/complicações , Dente Decíduo , Adulto JovemRESUMO
The physician who sees a newly diagnosed patient with diabetes can adequately fulfill his professional responsibilities by following a systematic approach to clinical diagnosis, investigations, appropriate treatment planning and involvement of the patient in is or her treatment through self-management education. Correct steps taken in the crucial initial period set the pace for optimum future management of this chronic disease.
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Diabetes Mellitus , Administração dos Cuidados ao Paciente , Diabetes Mellitus/classificação , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/etiologia , Monitoramento de Medicamentos , Teste de Tolerância a Glucose , Hospitalização , Humanos , Insulina/administração & dosagem , Anamnese , Exame Físico , AutocuidadoRESUMO
This case report describes a 9-year-old male who presented to the emergency department with 2 days' history of left painful red eye. On initial examination, his outside medical records indicated that he had bilateral subluxated lenses and had undergone left eye lensectomy with glued intrascleral fixation of an intraocular lens 8 weeks earlier. Vision in left eye was poor from first postoperative day but with no undue pain or redness, and poor vision was attributed to possible vitreous bleed. Subsequent postoperative course was uneventful. He was discharged from ophthalmic care on topical steroids and antibiotic drops, one week postsurgery. The eye was healing well until he developed pain, for which ophthalmic care was sought. He underwent anterior chamber tap with intravitreal injections. Aqueous samples were positive for Staphylococcus aureus DNA by polymerase chain reaction. Post vitrectomy and implant removal, his recovery was good and vision improved to 0.50 LogMar with aphakic correction.
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The effect of swift heavy ion (SHI) irradiation on InGaAs/GaAs heterostructures is studied using Raman spectroscopy and atomic force microscopy (AFM). The structures consist of molecular beam epitaxy (MBE) grown InGaAs layers on GaAs(001), having layer thicknesses of 12, 36, 60 and 96 nm. After irradiation, the GaAs type longitudinal optical (LO) mode blue shifted to higher frequency in thin samples and red shifted towards lower frequency in thick samples. These results are discussed invoking the penetration depth of the probe radiation (λ = 514.5 nm) in InGaAs. Deconvoluting the Raman spectra of thin samples indicates a compressive strain developed in the substrate, close to the interface upon irradiation. This modification and diffusion of indium across the interface results in an increase of strain and reduction of the defect densities in the InGaAs layer. The variations in FWHM of the Raman modes are discussed in detail. The surface morphology of these heterostructures has been studied by AFM before and after SHI irradiation. These studies, combined with Raman results, help to identify different relaxation regimes.
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The CXCR4 chemokine receptor has an important role in cancer cell metastasis. The CXCR4 antagonist, AMD3100, has limited efficacy in controlling metastasis. HuR, an RNA-binding protein, regulates CXCR4 in cancer cells. We therefore investigated whether targeting HuR using a siRNA-based nanoparticle plus AMD3100 would suppress CXCR4 and inhibit lung cancer metastasis. We treated human H1299 lung cancer cells with HuR-specific siRNA contained in a folate-targeted lipid nanoparticle (HuR-FNP) plus AMD3100, and compared this with AMD3100 alone, HuR-FNP alone and no treatment. HuR-FNP plus AMD3100 treatment produced a G1 phase cell cycle arrest and reduced cell viability above and beyond the effects of AMD3100 alone. HuR and CXCR4 mRNA and protein expression levels were markedly reduced in all treatment groups. Phosphorylated (p) AKT(S473) protein was also reduced. P27 protein expression increased with HuR-FNP and combination treatment. Promoter-based reporter studies showed that the combination inhibited CXCR4 promoter activity more than did either treatment alone. Cell migration and invasion was significantly reduced with all treatments; the combination provided the most inhibition. Reduced matrix metalloprotease (MMP)-2 and -9 expression was associated with reduced invasion in all treatment groups. Thus, we found that combined HuR and CXCR4 targeting effectively controlled lung cancer metastasis.
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Antineoplásicos/uso terapêutico , Proteína Semelhante a ELAV 1/antagonistas & inibidores , Compostos Heterocíclicos/uso terapêutico , Neoplasias Pulmonares/terapia , Nanopartículas/uso terapêutico , Receptores CXCR4/antagonistas & inibidores , Benzilaminas , Movimento Celular , Proliferação de Células , Terapia Combinada , Ciclamos , Regulação para Baixo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Nanopartículas/metabolismo , Invasividade Neoplásica , RNA Interferente Pequeno , Receptores CXCR4/genéticaRESUMO
Drug induced effects on the various endocrine and metabolic processes constitute a very common differential diagnostic possibility in investigating endocrine disorders. Knowledge of drug-effect is of paramount importance to avoid unnecessary and expensive investigations and treatment. Since most of the effects are type A effects and hence predictable, reduction of dose or modification of therapy is sufficient to reverse the adverse effects.
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Glândulas Endócrinas/efeitos dos fármacos , Glândulas Suprarrenais/efeitos dos fármacos , Osso e Ossos/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Glucose/metabolismo , Humanos , Masculino , Hormônios Hipofisários/metabolismo , Reprodução/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacosRESUMO
Growth hormone therapy with rhGH (recombinant human growth hormone) has been recommended for treatment of GH deficient short stature in children, repeated hypoglycemias in infancy and early childhood due to GH deficiency, short stature accompanying chronic renal failure prior to renal transplantation and Turner's syndrome. It is now increasingly recommended to adults with GH deficiency following pituitary tumour surgery or irradiation or idiopathic hypopituitarism. There are other indications for its use where evidence for protein catabolism is very strong such as burns injury. The end points of GH therapy in children include achievement of desirable adult height or a growth rate velocity of < 2.5 cm/year. In adults GH deficiency, GH therapy is intended for improvement of general well being, body composition and metabolic markers of GH function.
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Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Adulto , Estatura/efeitos dos fármacos , Criança , Interações Medicamentosas , Feminino , Transtornos do Crescimento/diagnóstico , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/deficiência , Humanos , Hipoglicemia/tratamento farmacológico , Hipoglicemia/etiologia , Hipopituitarismo/complicações , Fator de Crescimento Insulin-Like I/uso terapêutico , Masculino , Síndrome de Turner/tratamento farmacológicoRESUMO
BACKGROUND: Thyroid stimulating hormone (TSH) levels vary with the time of the day and probably in relation to food. In this study, we addressed the question of whether a fasting or non-fasting sample would make a clinically significant difference in the interpretation of thyroid function tests. MATERIALS AND METHODS: Fifty seven adult ambulatory patients were selected from our laboratory database and were divided into Group A [Normal free thyroxine (T4) and TSH], Group B (subclinical hypothyroid with increased TSH and normal free T4) and Group C (overt hypothyroid with low free T4 and high TSH). Thyroid functions (free T4 and TSH) were done in fasting state and 2 hours postprandially. RESULTS: TSH was suppressed in all subjects after food irrespective of the fasting levels. Free T4 values did not change significantly. This resulted in reclassification of 15 out of 20 (75%) subjects as subclinical hypothyroidism (SCH) based on fasting values whose TSH values were otherwise within range in the postprandial sample. This may have an impact on the diagnosis and management of hypothyroidism especially where even marginal changes in TSH may be clinically relevant as in SCH and in pregnancy. CONCLUSION: TSH levels showed a statistically significant decline postprandially in comparison to fasting values. This may have clinical implications in the diagnosis and management of hypothyroidism, especially SCH.
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A 7-month-old child presented with a 6-day history of right eyelid swelling and redness. She was being treated with chloramphenicol ointment and oral flucloxacillin by the general practitioner. Clinical examination revealed features of preseptal cellulitis. There was no evidence of orbital involvement and the child was generally well otherwise. Her oral antibiotics were changed and she was adviced to attend for a review in 2 days time. However, the child did not return for a review. Three weeks later following resolution of the eyelid swelling, the child represented with a divergent squint in the right eye. Clinical and orthoptic investigations suggested occlusion amblyopia. The child is currently receiving patching treatment for the amblyopia and is awaiting surgery for squint eye.