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We study the real-time dynamics of vortices in a large elongated Bose-Einstein condensate (BEC) of sodium atoms using a stroboscopic technique. Vortices are produced via the Kibble-Zurek mechanism in a quench across the BEC transition and they slowly precess keeping their orientation perpendicular to the long axis of the trap as expected for solitonic vortices in a highly anisotropic condensate. Good agreement with theoretical predictions is found for the precession period as a function of the orbit amplitude and the number of condensed atoms. In configurations with two or more vortices, we see signatures of vortex-vortex interaction in the shape and visibility of the orbits. In addition, when more than two vortices are present, their decay is faster than the thermal decay observed for one or two vortices. The possible role of vortex reconnection processes is discussed.
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INTRODUCTION: Postoperative pulmonary complications (PPCs) vary amongst different surgical techniques. We aim to compare the incidence of PPCs after laparoscopic non-robotic versus laparoscopic robotic abdominal surgery. METHODS AND ANALYSIS: LapRas (Risk Factors for PPCs in Laparoscopic Non-robotic vs Laparoscopic robotic abdominal surgery) incorporates harmonized data from 2 observational studies on abdominal surgery patients and PPCs: 'Local ASsessment of VEntilatory management during General Anaesthesia for Surgery' (LAS VEGAS), and 'Assessment of Ventilation during general AnesThesia for Robotic surgery' (AVATaR). The primary endpoint is the occurrence of one or more PPCs in the first five postoperative days. Secondary endpoints include the occurrence of each individual PPC, hospital length of stay and in-hospital mortality. Logistic regression models will be used to identify risk factors for PPCs in laparoscopic non-robotic versus laparoscopic robotic abdominal surgery. We will investigate whether differences in the occurrence of PPCs between the two groups are driven by differences in duration of anesthesia and/or the intensity of mechanical ventilation. ETHICS AND DISSEMINATION: This analysis will address a clinically relevant research question comparing laparoscopic and robotic assisted surgery. No additional ethical committee approval is required for this metanalysis. Data will be shared with the scientific community by abstracts and original articles submitted to peer-reviewed journals. REGISTRATION: The registration of this post-hoc analysis is pending; individual studies that were merged into the used database were registered at clinicaltrials.gov: LAS VEGAS with identifier NCT01601223, AVATaR with identifier NCT02989415.
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For many years, there has been a debate on the polluting loads affecting the Gulf of Naples, one of Italy's most spectacular and iconic landscape. The wide territory bordering the Gulf includes the Sarno river basin (SRB) managed by the Southern Apennines River Basin District Authority in the framework of Unit of Management Sarno (UoM-Sarno). The paper investigated the anthropogenic pressures and their spatial distribution in the UoM-Sarno, revealing as SRB represents a hotspot of pollution mainly due to the high population density and widespread hydro-demanding activities which are responsible of high organic and eutrophication loads. The pollution sources, variably distributed on the area, and potentially conveyed to the wastewater treatment plants (WWTPs) located into SRB, were estimated considering the WWTPs treatment capacity as well. Results revealed a holistic picture of UoM-Sarno area allowing to establish the priorities of the interventions aimed at safeguarding the coastal marine resources. In particular, 2590 tons BOD/year were directly discharged into the Gulf of Naples due to the missing of sewers, and other 10,600 tons BOD/year are potentially discharged in the Sarno river reaching the sea, considering the contribution of population, industrial activity, and livestock.
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The authors studied the correlation between the prescription of antimalarial drugs and the results of a rapid diagnostic test (RDT) and thick smear during dry and rainy seasons in a regional hospital outpatient clinic in North Cameroon. Clinical diagnosis, essentially based on the presence of fever, has a positive predictive value of 2% when compared with laboratory results during the dry season, against 44% during the rainy season. This study confirms the epidemic nature of malaria in the Sahelian zone of the North Region and challenges the currently available hospital statistics. In this epidemiological context, the authors recommend routine laboratory diagnosis of malaria before any treatment, especially during the dry season. This is justified both therapeutically and economically.
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Criança Hospitalizada/estatística & dados numéricos , Erros de Diagnóstico/estatística & dados numéricos , Malária/diagnóstico , Malária/epidemiologia , Antimaláricos/economia , Antimaláricos/uso terapêutico , Camarões/epidemiologia , Pré-Escolar , Custos e Análise de Custo , Erros de Diagnóstico/economia , Reações Falso-Positivas , Hospitais , Humanos , Lactente , Recém-Nascido , Malária/tratamento farmacológico , Malária/economia , Valor Preditivo dos Testes , Prevalência , Reprodutibilidade dos Testes , Estações do AnoRESUMO
Single-walled carbon nanotubes (SWNTs) due to their unique structural and physicochemical properties, have been proposed as delivery systems for a variety of diagnostic and therapeutic agents. However, SWNTs have proven difficult to solubilize in aqueous solution, limiting their use in biological applications. In an attempt to improve SWNTs' solubility, biocompatibility, and to increase cell penetration we have thoroughly investigated the construction of carbon scaffolds coated with aliphatic carbon chains and phospholipids to obtain micelle-like structures. At first, oxidized SWNTs (2370 ± 30 nmol mg(-1) of SWNTs) were covalently coupled with an alcoholic chain (stearyl alcohol, C(18)H(37)OH; 816 nmol mg(-1) of SWNTs). Subsequently, SWNTs-COOC(18)H(37) derivatives were coated with phosphatidylethanolamine (PE) or -serine (PS) phospholipids obtaining micelle-like structures. We found that cellular uptake of these constructs by phagocytic cells occurs via an endocytotic mechanism for constructs larger than 400 nm while occurs via diffusion through the cell membrane for constructs up to 400 nm. The material that enters the cell by phagocytosis is actively internalized by macrophages and localizes inside endocytotic vesicles. In contrast the material that enters the cells by diffusion is found in the cell cytosol. In conclusion, we have realized new biomimetic constructs based on alkylated SWNTs coated with phospholipids that are efficiently internalized by different cell types only if their size is lower than 400 nm. These constructs are not toxic to the cells and could now be explored as delivery systems for non-permeant cargoes.
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Membrana Celular/metabolismo , Álcoois Graxos/química , Nanotubos de Carbono/química , Fosfolipídeos/química , Linhagem Celular , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Sobrevivência Celular , Álcoois Graxos/farmacocinética , Humanos , Macrófagos/citologia , Micelas , Nanotubos de Carbono/ultraestrutura , Oxirredução , Fagocitose , Fosfolipídeos/farmacocinética , SolubilidadeRESUMO
A 28-year-old female patient came to our clinic complaining of small central visual field defects in both eyes, without any impairments of visual acuity. She reported recent flu-like symptoms and work-related stress associated with high caffeine intake. Dark reddish cloverleaf-shaped lesions were noted in the macular region with red-free fundoscopy, and alterations of the external retinal layers were observed in spectral domain optical coherence tomography (SD-OCT). The visual field test (Octopus, program 32) revealed small central scotoma on both eyes. The fluorescein angiograms were normal. A suspected diagnosis of acute macular neuroretinopathy (AMNR) was made and the patient was scheduled for follow-up 4 weeks later. The follow-up examination showed persisting central scotoma as well as persistence of the lesions in the external retinal layers in OCT. The best-corrected visual acuity was still 20/20. In OCT angiography (OCT-A), a reduced correlation signal and therefore perfusion was detected in the outer retinal capillary plexus within the area of the fundoscopic macular lesions. Multimodal imaging, including SD-OCT and AOCT, plays a pivotal role in the diagnosis of acute macular neuroretinopathy. Even though no serious impairments of visual acuity are reported, patients should be informed about the possibility of permanent central scotoma.
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Doenças Retinianas , Testes de Campo Visual , Adulto , Feminino , Angiofluoresceinografia , Humanos , Tomografia de Coerência Óptica , Acuidade Visual , Campos VisuaisRESUMO
Drug delivery has been greatly improved over the years by means of chemical and physical agents that increase bioavailability, improve pharmacokinetic and reduce toxicities. At the same time, cell based delivery systems have also been developed. These possesses a number of advantages including prolonged delivery times, targeting of drugs to specialized cell compartments and biocompatibility. Here we'll focus on erythrocyte-based drug delivery. These systems are especially efficient in releasing drugs in circulations for weeks, have a large capacity, can be easily processed and could accommodate traditional and biologic drugs. These carriers have also been used for delivering antigens and/or contrasting agents. Carrier erythrocytes have been evaluated in thousands of drug administration in humans proving safety and efficacy of the treatments. Erythrocyte-based delivery of new and conventional drugs is thus experiencing increasing interests in drug delivery and in managing complex pathologies especially when side effects could become serious issues.
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Transplante de Células/métodos , Sistemas de Liberação de Medicamentos/métodos , Eritrócitos/citologia , Animais , Portadores de Fármacos , Eritrócitos/química , Eritrócitos/metabolismo , Humanos , Macrófagos/metabolismo , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/metabolismoRESUMO
OBJECTIVE: Ischemic preconditioning (IPC) was developed to diminish ischemia-reperfusion injury (IRI). There are two main ways of performing it: direct ischemic-preconditioning (DIP) and remote ischemic-preconditioning (RIP). The objectives of this study were to investigate local and systemic effects of DIP and RIP in liver IRI. METHODS: Thirty-two weaning rats (50-70 g body weight; 21 days old) were divided into 4 groups: control (C); ischemia followed by reperfusion (IR); DIP followed by ischemia and reperfusion; and RIP followed by ischemia and reperfusion. In the IR group, the vascular pedicles of medial and left lateral liver lobes were clamped for 60 minutes and then unclamped. In the DIP group, a 10-minute cycle of ischemia followed by a 10-minute reperfusion of the same lobes was performed before 60 minutes of ischemia. In the RIP group, three 5-minute cycles of clamping and unclamping of the femoral vessels were performed before liver ischemia. The animals were euthanized 24 hours after the surgical procedures. RESULTS: The serum levels of liver enzymes were significantly lower in the RIP group compared to the control and IR groups and to the DIP group. The scores of histologic hepatic lesions were significantly lower in RIP animals than those of IR animals (P = .002) and similar to the C group animals. The Bax/BCl-xl relation was lower in the DIP group than that in the RIP group (P = .045) and no differences were observed in histologic analyses of kidney, lung, intestine, and heart. CONCLUSION: In young animals, the beneficial effects of RIP are more evident than those of DIP.
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Precondicionamento Isquêmico/métodos , Fígado/irrigação sanguínea , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Fígado/patologia , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologiaRESUMO
BACKGROUND: Inflammatory bowel disease (IBD) present in childhood in 15% to 25% of cases. The aim of therapy in children is not only to guarantee normal growth but also to prevent relapse and to maintain remission. Steroids are effective to induce remission; however, resistance, dependency, and irreversible side effects can develop. The aim of this study was to determine whether treatment with repeated infusions of autologous red blood cells (RBCs) loaded with dexamethasone 21-phosphate (Dex 21-P) is safe and allows maintenance of long-term remission in children with steroid-dependent Crohn disease (CD). PATIENTS AND METHODS: Eighteen consecutive pediatric patients who met the inclusion criteria were admitted to the study. Infusions of autologous RBCs loaded with Dex 21-P were performed every 4 weeks; the mean duration of treatment was 24 months. At the beginning of treatment and after 6, 12, and 24 months, we performed clinical evaluation according to the Pediatric Crohn Disease Activity Index (pCDAI). Assessment of body mass in dexamethasone and bone mineral density by means of computerized bone mineralometry-dual energy x-ray absorptiometry, endoscopic evaluation, and hematic morning cortisol determination were also performed. RESULTS: During treatment, the mean pCDAI significantly decreased (P < 0.05); 78% of patients discontinued steroids. Determination of morning cortisol showed suppression only on the first day after infusion, followed by normalization of values. Endoscopic findings showed remission in 44% of patients. None of the patients experienced serious side effects. CONCLUSIONS: These data suggest that repeated infusions of RBCs loaded with Dex 21-P can be safe and useful to maintain long-term remission in pediatric patients with moderately active CD.
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Anti-Inflamatórios/administração & dosagem , Doença de Crohn/terapia , Dexametasona/análogos & derivados , Transfusão de Eritrócitos/métodos , Adolescente , Transfusão de Sangue Autóloga , Criança , Pré-Escolar , Dexametasona/administração & dosagem , Feminino , Humanos , Masculino , Projetos Piloto , Indução de RemissãoRESUMO
Homo- and heterodimers of nucleoside/nucleotide analogues as reverse transcriptase inhibitors are effective on HIV-1-infected human monocyte-derived macrophages (M/M) compared to the single drugs or their combination. Since the combined treatment of lamivudine (3TC) and tenofovir ((R)PMPA) has an antiretroviral efficacy and a synergic effect respect to separate drugs, the heterodinucleotide 3TCpPMPA was synthesized. A single administration of the dimer as free drug or 3TCpPMPA-loaded RBC selectively targeted to M/M was able to almost completely protect macrophages from "de novo" infection.
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Adenina/análogos & derivados , Fármacos Anti-HIV/administração & dosagem , Lamivudina/análogos & derivados , Organofosfonatos/administração & dosagem , Adenina/administração & dosagem , Adenina/síntese química , Adenina/química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Eritrócitos/metabolismo , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Técnicas In Vitro , Lamivudina/administração & dosagem , Lamivudina/síntese química , Lamivudina/química , Macrófagos/efeitos dos fármacos , Macrófagos/virologia , Organofosfonatos/síntese química , Organofosfonatos/química , Tenofovir , Replicação Viral/efeitos dos fármacosRESUMO
BACKGROUND: We have recently demonstrated that low doses of Dexamethasone 21-P (Dex 21-P), loaded in autologous erythrocytes and administered at monthly intervals, have been able to maintain steroid-dependent patients with Crohn's disease (CD) and ulcerative colitis (UC) in clinical remission with a progressive and complete tapering of systemic steroids. AIM: Since multi-drug resistance 1 gene (MDR1) has a potential influence on Dexamethasone (Dex) bioavailability, we designed this study to investigate the correlation between MDR1 genotype and Dex pharmacokinetic after its delivery in patients with inflammatory bowel disease (IBD). MATERIALS AND METHODS: Seventeen steroid-dependent consecutive patients with IBD (10 UC mean age 36 +/- 12, and 7 Crohn's disease mean age 31 +/- 5) were consecutively recruited. The C3435T polymorphism of MDR1 gene was studied by Denaturing High Performance Liquid Chromatography (DHPLC). Serum level of Dex were determined at the end of the infusion and after 15 days by high performance liquid chromatography electrospray mass spectrometry. RESULTS: The mean dose of Dex 21-P administered was 9.9 mg +/- 4 (range 2.7-20.3), while the mean levels of Dex at the end of the infusion and after 15 days were 0.66 +/- 0.23 mM and 0.06 +/- 0.06 mM, respectively. Concerning the C3435T genotype, two patients were wild-type, eleven heterozygotes, and four homozygotes. No correlation between basal or 15-days plasma level of Dex and MDR1 genotype was found (r = 0.19 and r = 0.21, respectively). CONCLUSION: Our findings demonstrated that Dex plasma level, after infusion of autologous erythrocytes loaded with Dex 21-P are completely independent by the MDR 1 gene polymorphism. This could be another potential advantage of this modality of drug delivering.
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Colite Ulcerativa/genética , Doença de Crohn/genética , Dexametasona/análogos & derivados , Genes MDR/genética , Pró-Fármacos/farmacocinética , Adulto , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Doença de Crohn/tratamento farmacológico , Doença de Crohn/metabolismo , Dexametasona/administração & dosagem , Dexametasona/sangue , Dexametasona/farmacocinética , Portadores de Fármacos , Eritrócitos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Pró-Fármacos/administração & dosagemRESUMO
PURPOSE: To compare the cost effectiveness of low-molecular-weight heparin with that of oral anticoagulants in preventing recurrences after an episode of venous thromboembolism. METHODS: A decision tree was used to assess the cost and the expected quality-adjusted years of life (QALY) after treatment with either low-molecular-weight heparin or warfarin, based on pooled data from six published trials. Preferences were elicited with a modified time trade-off method in a sample of patients attending an anticoagulation clinic. RESULTS: Compared with warfarin, low-molecular-weight heparin significantly decreased the rate of minor bleeding (odds ratio [OR] = 0.24; 95% confidence interval [CI]: 0.14 to 0.43) but not recurrent deep vein thromboses (OR = 0.77; 95% CI: 0.43 to 1.35). Patients' preference for warfarin (0.988, on a 0 to 1 scale) was lower than that for low-molecular-weight heparin (0.992), but the difference was not statistically significant. A Monte Carlo analysis estimated that low-molecular-weight heparin saved an average of 13 quality-adjusted days compared with warfarin, at a cost of $6,583 per QALY (95% CI: $5,525 to $7,625) based on costs in Italy and $28,231 per QALY (95% CI: $20,872 to $36,773) based on costs in the United States. When we included rebound recurrences after interruption of therapy, which were more common with low-molecular-weight heparin, treatment with low-molecular-weight heparin cost $53,166 per QALY in Italy and $177,166 per QALY in the United States. CONCLUSIONS: Low-molecular-weight heparin might be a cost-effective drug for secondary prophylaxis of venous thromboembolism, especially in patients at high risk of recurrence and where the drug's cost is lower. The apparent increase in recurrence after interruption of therapy needs to be investigated more thoroughly before low-molecular-weight heparin can be recommended routinely.
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Anticoagulantes/economia , Heparina de Baixo Peso Molecular/economia , Tromboembolia/economia , Tromboembolia/prevenção & controle , Varfarina/economia , Administração Oral , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Análise Custo-Benefício , Árvores de Decisões , Hemorragia/induzido quimicamente , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/efeitos adversos , Humanos , Itália , Razão de Chances , Satisfação do Paciente , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Prevenção Secundária , Estados Unidos , Varfarina/administração & dosagem , Varfarina/efeitos adversosRESUMO
During fMRI, dyslexic and control boys completed auditory language tasks (judging whether pairs of real and/or pseudo words rhymed or were real words) in 30 s 'on' conditions alternating with a 30 s 'off' condition (judging whether tone pairs were same). During phonological judgment, dyslexics had more activity than controls in right than left inferior temporal gyrus and in left precentral gyrus. During lexical judgment, dyslexics were less active than controls in bilateral middle frontal gyrus and more active than controls in left orbital frontal cortex. Individual dyslexics were reliably less active than controls in left insula and left inferior temporal gyrus. Dyslexic and control children differ in brain activation during auditory language processing skills that do not require reading.
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Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Dislexia/fisiopatologia , Leitura , Estimulação Acústica/métodos , Adolescente , Análise de Variância , Percepção Auditiva/fisiologia , Córtex Cerebral/fisiopatologia , Criança , Humanos , Imageamento por Ressonância Magnética/métodos , MasculinoRESUMO
Monocyte-derived macrophages (M/M) are considered important in vivo reservoirs for different kinds of viruses, including HIV. Hence, therapeutic strategies are urgently needed to protect these cells from virus infection or to control viral replication. In this paper, we report the synthesis, target delivery and in vitro efficacy of a new heterodinucleotide (AZTpPMPA), able to inhibit HIV-1 production in human macrophages. AZTpPMPA consists of two established anti-HIV drugs [zidovudine (AZT) and tenofovir (PMPA)] chemically coupled together by a phosphate bridge. This drug is not able to prevent p24 production when administered for 18 h to M/M experimentally infected with HIV-1 Bal (inhibition 27%), but can almost completely suppress virus production when given encapsulated into autologous erythrocytes (inhibition of p24 production 97%). AZTpPMPA is slowly converted to PMPA, AZT monophosphate and AZT (36 h half-life at 37 degrees C) by cell-resident enzymes. Thus AZTpPMPA should be considered a new prodrug of AZT and PMPA that is able to provide stechiometric amounts of both nucleoside analogues to macrophage cells and to overcome the low phosphorylating activity of M/M for AZT and the modest permeability of PMPA.
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Adenina/farmacologia , Fármacos Anti-HIV/farmacologia , Sistemas de Liberação de Medicamentos , Eritrócitos/metabolismo , HIV-1/efeitos dos fármacos , Macrófagos/virologia , Zidovudina/farmacologia , Adenina/análogos & derivados , Adenina/química , Adenina/metabolismo , Fármacos Anti-HIV/química , Fármacos Anti-HIV/metabolismo , Adesão Celular , Cromatografia Líquida de Alta Pressão , Didesoxinucleotídeos , Estabilidade de Medicamentos , Humanos , Técnicas In Vitro , Macrófagos/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Zidovudina/análogos & derivados , Zidovudina/química , Zidovudina/metabolismoRESUMO
PURPOSE: To use MR spectroscopy to study the biochemical changes produced by auditory stimuli in patients with sudden sensorineural hearing loss and to compare these findings with the biochemical changes seen in healthy volunteers. METHODS: Single-voxel MR spectroscopy was used to study biochemical changes in the auditory cortex in 11 control subjects and 19 patients with sudden sensorineural hearing loss. MR spectroscopic signals were measured during three different sound conditions (scanner noise, music, and sirens). RESULTS: A lower MR spectroscopic lactate signal was observed in control subjects during the music stimulus than during the other sound conditions. This music-induced lactate change was not observed in patients with hearing loss. The other proton metabolites (choline, creatine, N-acetylaspartate [NAA]) remained stable during the different auditory stimuli. However, the NAA/creatine ratio was higher in the auditory cortex of patients than in the control subjects, and was not dependent on the sound condition. CONCLUSION: The detection of stimulus-induced and stable biochemical MR spectroscopic changes in patients with hearing loss may be useful in assessing disease activity.
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Córtex Auditivo/metabolismo , Perda Auditiva Súbita/metabolismo , Espectroscopia de Ressonância Magnética , Estimulação Acústica , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Audiometria de Resposta Evocada , Córtex Auditivo/fisiologia , Percepção Auditiva , Colina/metabolismo , Creatina/metabolismo , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Seguimentos , Audição , Perda Auditiva Neurossensorial/metabolismo , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/fisiopatologia , Humanos , Lactatos/metabolismo , Masculino , Música , RuídoRESUMO
PURPOSE: Our purpose was to compare cerebral proton MR metabolite changes in patients with multiple sclerosis (MS) and abnormal visual evoked potentials (VEPs) with those in MS patients with normal VEPs. METHODS: Seventeen subjects with clinically definite MS were studied with VEPs and MR spectroscopic imaging. Proton MR metabolites were measured using a fast spectroscopic imaging technique called proton echo-planar spectroscopic imaging (PEPSI). Kurtzke's Expanded Disability Status Scale (EDSS) score was also ascertained for each subject to obtain a clinical rating. Twelve regions of interest within the visual pathway of the cerebrum were evaluated for levels of N-acetylaspartate (NAA), choline, creatine, and the presence or absence of MR-detectable lesions. RESULTS: PEPSI NAA values (water-normalized, CSF-corrected) were significantly lower in MS subjects with abnormal VEPs than in subjects with normal VEPs. MR-detectable lesion fractions and EDSS scores were also significantly different between the two VEP groups, but NAA comparison had a P value 100 times less than either of these measures. CONCLUSION: In patients with MS, NAA measurements in the optic pathways of the brain were sensitive to VEP abnormalities. NAA was more sensitive to VEP changes than were choline, creatine, MR-detectable lesions, and EDSS score.
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Ácido Aspártico/análogos & derivados , Potenciais Evocados Visuais/fisiologia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Esclerose Múltipla/diagnóstico , Neuromielite Óptica/diagnóstico , Adulto , Ácido Aspártico/metabolismo , Mapeamento Encefálico , Colina/metabolismo , Creatina/metabolismo , Avaliação da Deficiência , Imagem Ecoplanar , Eletroencefalografia , Feminino , Humanos , Masculino , Esclerose Múltipla/fisiopatologia , Exame Neurológico , Neuromielite Óptica/fisiopatologia , Lobo Occipital/patologia , Lobo Occipital/fisiopatologia , Processamento de Sinais Assistido por Computador , Vias Visuais/patologia , Vias Visuais/fisiopatologiaRESUMO
BACKGROUND AND PURPOSE: Dyslexia is a language disorder in which reading ability is compromised because of poor phonologic skills. The purpose of this study was to measure the effect of a phonologically driven treatment for dyslexia on brain lactate response to language stimulation as measured by proton MR spectroscopic imaging. METHODS: Brain lactate metabolism was measured at two different time points (1 year apart) during four different cognitive tasks (three language tasks and one nonlanguage task) in dyslexic participants (n = 8) and in control participants (n = 7) by using a fast MR spectroscopic imaging technique called proton echo-planar spectroscopic imaging (1 cm3 voxel resolution). The age range for both dyslexic and control participants was 10 to 13 years. Between the first and second imaging sessions, the dyslexic boys participated in an instructional intervention, which was a reading/science workshop. RESULTS: Before treatment, the dyslexic boys showed significantly greater lactate elevation compared with a control group in the left anterior quadrant (analysis of variance, P = .05) of the brain during a phonologic task. After treatment, however, brain lactate elevation was not significantly different from that of the control group in the left anterior quadrant during the same phonologic task. Behaviorally, the dyslexic participants improved in the phonologic aspects of reading. CONCLUSION: Instructional intervention that improved phonologic performance in dyslexic boys was associated with changes in brain lactate levels as measured by proton echo-planar spectroscopic imaging.
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Dislexia/terapia , Ácido Láctico/metabolismo , Espectroscopia de Ressonância Magnética , Fonética , Encéfalo/fisiopatologia , Criança , Dislexia/diagnóstico , Dislexia/fisiopatologia , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Ensino de Recuperação , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: Children with dyslexia have difficulty learning to recognize written words owing to subtle deficits in oral language related to processing sounds and accessing words automatically. The purpose of this study was to compare regional changes in brain lactate between dyslexic children and control subjects during oral language activation. METHODS: Brain lactate metabolism was measured during four different cognitive tasks (three language tasks and one nonlanguage task) in six dyslexic boys and in seven control subjects (age- and IQ-matched right-handed boys who are good readers) using a fast MR spectroscopic imaging technique called proton echo-planar spectroscopic imaging (1-cm3 voxel resolution). The area under the N-acetylaspartate (NAA) and lactate peaks was measured to calculate the lactate/NAA ratio in each voxel. RESULTS: Dyslexic boys showed a greater area of brain lactate elevation (2.33+/-SE 0.843 voxels) as compared with the control group (0.57+/-SE 0.30 voxels) during a phonological task in the left anterior quadrant. No significant differences were observed in the nonlanguage tasks. CONCLUSION: Dyslexic and control children differ in brain lactate metabolism when performing language tasks, but do not differ in nonlanguage auditory tasks.
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Encéfalo/fisiopatologia , Dislexia/fisiopatologia , Imagem Ecoplanar , Ácido Láctico/metabolismo , Espectroscopia de Ressonância Magnética , Aprendizagem Verbal/fisiologia , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Percepção Auditiva/fisiologia , Mapeamento Encefálico , Criança , Humanos , Masculino , Valores de Referência , Percepção da Fala/fisiologiaRESUMO
Endothelin-1,2 urinary excretion, has been determined in control and streptozotocin diabetic rats at different times after diabetes induction. Diabetic rats showed increased urinary excretion of endothelins as compared to control rats, already three days after diabetes induction and up to 20 weeks.
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Diabetes Mellitus Experimental/urina , Endotelinas/urina , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Endotelinas/metabolismo , Endotélio Vascular/metabolismo , Masculino , Ratos , Ratos Brattleboro , EstreptozocinaRESUMO
Exposure of 4-methoxy-2-(3-phenyl-2-propynyl)phenol (CO/1828) to air and light (accelerated by temperature) yields 1-(2-hydroxy-5- methoxyphenyl)-3-phenylpropynone as the major degradation product. With extraction, this product rapidly degrades to 5-methoxyaurone and 6-methoxyflavone. In addition, a mixture of dimeric and heterodimeric compounds that are not fully identified was observed. These results indicate the formation of a reactive ortho-quinone methide as an unstable intermediate. This hypothesis is supported by evidence that the aurone slowly isomerizes into the flavone in control samples. Identification of compounds was accomplished with mass spectrometry, nuclear magnetic resonance spectrometry, UV-high-performance liquid chromatography, and comparison with authentic samples.