A interrelação entre memória operacional e apraxia de fala

The present study aimed to verify the relationship between working memory (WM) and apraxia of speech and explored which WM components were involved in the motor planning of speech. A total of 22 patients and 22 healthy adults were studied. These patients were selected according to the following inclusion criteria: a single brain lesion in the left hemisphere, presence of apraxia of speech and sufficient oral comprehension. This study involved assessment of apraxia of speech and evaluation of working memory capacity. The performance of apraxic patients was significantly poorer than that of controls, where this reached statistical significance. The study concluded that participants with apraxia of speech presented a working memory deficit and that this was probably related to the articulatory process of the phonoarticulatory loop. Furthermore, all apraxic patients presented a compromise in working memory.O objetivo do presente estudo foi verificar a interrelação entre memória operacional e apraxia verbal e explorar quais os componentes desta memória estariam envolvidos na programação motora da fala. Foram avaliados 22 pacientes apráxicos e 22 controles. Todos os participantes foram submetidos a avaliação da apraxia de fala. Para investigar a memória operacional, foram aplicados o teste de span de dígitos na ordem direta e inversa, um teste de repetição de palavras longas e curtas e o Rey Auditory Verbal Learning Test, que investiga, além da alça articulatória, o buffer episódico. O desempenho dos apráxicos em todos os testes de memória foi estatisticamente significante mais baixo que o desempenho dos controles. Concluímos que indivíduos com apraxia apresentam um déficit na memória operacional e que este déficit está mais relacionado ao processo articulatório da alça fonoarticulatória.Universidade Federal de São Paulo (UNIFESP) Department of Speech PathologyUNIFESP, Department of Speech PathologySciEL

Unstructured MEL modelling of non linear 3D Ship hydrodynamics

In the present work the investigations of non linear effects, in the context of potential flow theory, are investigated. These effects are caused by three main reasons, namely: the changes of the wetted geometry of the floating body, the water line dynamics and the fully non linear nature of the free surface boundary conditions. In order to understand the importance of tackling the non linear effects, a three dimensional frequency study of the S175 conteinership is carried out, at different Froude numbers, using linear frequency domain methods and a partly non linear time domain method.A time domain analysis, with the aid of an unstructured mixed Eulerian Lagrangian (MEL) description of the fluid flow, is implemented aiming in exploring potential low non linear effects. In this framework, the mixed boundary value problem of the Eulerian phase of the MEL scheme is tackled by means of a Boundary Element Method using constant elements (or a direct Rankine panel method). At given time step, on Neumann boundaries the impervious boundary condition is specified whereas, on Dirichlet boundaries, the potential on the free surface is prescribed. The solution of the Boundary Value problem yields the potential on the Neumann boundaries and its normal derivative on Dirichlet boundaries. In the Lagrangian phase, the free surface boundary conditions are then integrated in time. This method was used to solve the linear time domain radiation, i.e by applying linearized free surface boundary conditions on the exact free surface and solving the mixed boundary value problem on the mean undisturbed free surface, for the case of forced motions of a hemisphere and a Wigley hull. In addition, the linear time domain method is also extended to the unified hydroelastic analysis in time domain for the cases of 2 and 3 nodes bending. Results are presented for the Wigley hull, undergoing prescribed forced oscillations for both rigid and flexible mode shapes.The extension of the MEL scheme to a numerical tool capable of addressing several degrees of non linearities (from body nonlinear to fully nonlinear) is also discussed. In this context, two numerical formulations to calculate the time derivative of the velocity potential are implemented, namely: a backward finite scheme and an exact calculation based in the time harmonic property of the velocity potential. In latter case, a second boundary value problem is constructed and solved for the time derivative of the potential on Neumann boundaries and for the normal acceleration on Dirichlet boundaries. Results of both approaches are compared for the case of a sphere undergoing force oscillations in heave are compared to results obtained by other time domain methods. Moreover, after the boundary value problem is solved, a radial basis function representation of the velocity potential and free surface elevation is constructed, this approach allows for the estimation of the gradient of the velocity potential (body nonlinear and fully nonlinear simulations) and free surface steepness (fully nonlinear simulations). The results of the body non linear analysis, for large amplitude of oscillation in heave, are presented for the both the sphere and Wigley hull. For the latter, body non linear results of the coupling between heave into the first distortion mode (2-node) are also presented. The results of the fully non linear simulations are presented for the case of a sphere.An investigation of the suitability of two unstructured meshing libraries is also performed in the context of the MEL simulation scheme. Practical issues related to (re)meshing at each time step, the representation of ship like geometries, free surface evolution and numerical stability are highlighted for both libraries

Effect of an antiandrogenic H<inf>2</inf> receptor antagonist on hepatic regeneration in rats

Because biochemical 'feminization' of the liver in males is observed with hepatic regeneration and because the hepatic regenerative response in females is greater than that in males, the posibility that antiandrogens might potentiate liver regeneration was investigated. Before 70% hepatectomy, adult male Wistar rats were treated with cimetidine, and antiandrogenic H2 antagonist, at doses up to 10 times greater than those used clinically. Control animals received either the saline vehicle or ranitidine, an H2 antagonist without antiandrogenic properties. Treatment with cimetidine reduced the hepatic cytosolic androgen receptor content compared with ranitidine treatment. Hepatectomy caused a further reduction in androgen receptor activity in all groups. Hepatic cytosolic estrogen receptor activity was comparable in all groups throughout the study. Moreover, the rate of liver growth and the levels of ornithine decarboxylase and thymidine kinase activity induced as part of the regenerative response were similar in all groups. Thus, cimetidine, despite its ability to bind to androgen receptors, and ranitidine, an H2 receptor antagonist without antiandrogen action, do not modulate the hepatic regenerative response to a 70% partial hepatectomy

Orthotopic liver transplantation for massive hepatic lymphangiomatosis

Lymphangiomatosis is a rare malformation of the lymphatic system that causes severe symptoms secondary to progressive growth into or close to vital structures. A case report of liver failure related to this space-occupying intrahepatic mechanism is taken as a starting point for a discussion of the problems of liver transplantation related to large hepatomegalies. © 1988

Liver transplantation for arteriohepatic dysplasia (Alagille's syndrome)

Thirteen out of 268 children (<18 years old) underwent hepatic transplantation (OLT) for end-stage liver disease (ESLD) associated with arteriohepatic dysplasia (AHD). Seven children are alive and well with normal liver function. Six children died, four within 11 days of the operation and the other two at 4 and 10 months after the OLT. Vascular complications with associated septicemia were responsible for the deaths of three children. Two died of heart failure and circulatory collapse, secondary to pulmonary hypertension and congenital heart disease. The remaining patient died of overwhelming sepsis not associated with technical complications. Seven patients had a portoenterostomy or portocholecystostomy early in life; five of these died after the OLT. Severe cardiovascular abnormalities in some of our patients suggest that complete hemodynamic monitoring with invasive studies should be performed in all patients with AHD, especially in cases of documented hypertrophy of the right ventricle. The improved quality of life in our surviving patients confirms the validity of OLT as a treatment of choice in cases of ESLD due to AHD. © 1992 Springer-Verlag

Amelioration of normothermic canine liver ischemia with prostacyclin.

A model of hepatic ischemia was developed in dogs using a pump-driven splanchnic-to-jugular vein bypass during crossclamping of the portal triad. An LD50 was established with three hours of ischemia. PGI2 given for one hour before the ischemic insult ameliorated the ischemic injury and increased survival

Orthotopic liver transplantation in dogs receiving FK-506.

Ten dogs that survived the perioperative events of liver transplantation were treated with 1 mg/kg/d oral FK. Eight of the recipients lived for at least 1 month postoperatively, and seven are still alive with normal hepatic function after 35 to 65 days. The consistency and good quality of results with this difficult transplant preparation using FK, in spite of its rumored great toxicity in dogs, have highlighted the importance of further developing the drug

Effect of FK506 in experimental organ transplantation.

FK506 is the most potent immunosuppressive agent known. Its toxicity is substantial in dogs, minor in rats, and unknown in subhuman primates. In small doses that are nontoxic even in dogs, it can be used in synergistic combination with cyclosporine, steroids, and presumably in other drugs

Spinocerebellar ataxia: perceptual and acoustic analysis of speech in three cases

BACKGROUND: dysarthrias are commonly found in patients with spinocerebellar ataxias (SCA). AIM: to characterize perceptual and acoustic features of speech in three patients with spinocerebellar ataxia and to verify the presence of similar features among these patients. METHOD: speech samples of two males with SCA3 and one male with SCA2 were obtained. Both perceptual and acoustic analyses were done. RESULTS: It was observed strain-strangled and breathiness phonation, vocal instability, increased noise-to-harmonics ratio and low alternate motion rate (AMR) and speech rate in all three patients. Deviated resonance and s/z ratio were also observed. CONCLUSION: phonatory disorders and altered temporal patterns of speech seem to be typical in dysarthric patients with spinocerebellar ataxia.TEMA: a disartria é freqüentemente descrita como característica marcante dentre as diversas manifestações clínicas das ataxias espinocerebelares (AEC). OBJETIVO: caracterizar as alterações perceptivo-auditivas e acústicas da fala de três pacientes com ataxia espinocerebelar e verificar a presença de manifestações comuns entre os casos. MÉTODO: amostras de fala de dois homens com AEC-3 e de um com AEC-2 foram coletadas e analisadas acústica e perceptivamente. RESULTADOS: foi identificada voz tensa e soprosa, instabilidade vocal, aumento da proporção ruído-harmônico, redução da diadococinesia oral de sílabas alternadas e redução da velocidade da fala nos três indivíduos, além de desvios ressonantais e da relação s/z. CONCLUSÃO: manifestações fonatórias e dos padrões temporais da fala parecem ser características de pacientes disártricos com ataxia espinocerebelar.Universidade Federal de São Paulo (UNIFESP) Prefeitura do Rio de JaneiroUNIFESP Atenção Básica à SaúdeRede Sarah Hospitais de ReabilitaçãoUNIFESP Departamento de FonoaudiologiaUNIFESP, Prefeitura do Rio de JaneiroUNIFESP, Atenção Básica à SaúdeUNIFESP, Depto. de FonoaudiologiaSciEL