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1.
Br J Neurosurg ; 37(5): 1228-1232, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33095069

RESUMO

Gliomas involving the cranial nerves III-XIII are rare. Even rarer are glioblastomas multiforme (GBMs) with only 10 cases previously reported. Oculomotor nerve involvement was described in only 2 patients. The mechanisms proposed so far include an origin from the nerve itself or an extension within the nerve of a midbrain tumor. We report the case of a 69-year-old man who presented with an isolated left oculomotor nerve palsy. He was found to have a left temporal GBM extended to the frontal lobe. Diagnostics and intraoperative and pathological findings clearly demonstrated a massive infiltration of the cisternal portion of the left oculomotor nerve. We suppose this could be the first case of direct oculomotor nerve invasion by exophytic spread of a supratentorial GBM or by subarachnoid seeding from a temporal tumor. Less probably, it could be the first case of an oculomotor nerve GBM with a temporal lobe invasion.


Assuntos
Neoplasias do Tronco Encefálico , Glioblastoma , Glioma , Doenças do Nervo Oculomotor , Masculino , Humanos , Idoso , Nervo Oculomotor/diagnóstico por imagem , Nervo Oculomotor/patologia , Glioblastoma/diagnóstico , Glioblastoma/diagnóstico por imagem , Doenças do Nervo Oculomotor/etiologia , Doenças do Nervo Oculomotor/cirurgia , Glioma/complicações , Neoplasias do Tronco Encefálico/complicações
2.
Brain Spine ; 2: 100909, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248151

RESUMO

•New insight into prognostic factors for recovery of clinical function following posterior decompression for degenerative cervical myelopathy.•An increase of IOM amplitude of at least 50% coupled with preoperative T2-only and diffuse T2 signal changes on MRI is a positive prognostic factors for clinical improvement 6 months after surgery.•Clinical improvement at 6 months follow-up can be expected in patients with T1 hypo intensity if a diffuse border of the lesion on T2 images is present.

3.
Br J Neurosurg ; : 1-5, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33970733

RESUMO

BACKGROUND AND IMPORTANCE: Intramedullary spinal cord metastases (ISCMs) are rare and no cases of ISCM from an adenoid cystic carcinoma (ACC) of the external auditory canal (EAC) have been reported. CLINICAL PRESENTATION: We report a 54-year old man complaining backpain and worsening myelopathy. He had an ACC of the EAC resected years prior. A spinal MRI demonstrated a contrast-enhancing intramedullary lesion within the conus medullaris. The histopathological diagnosis of the patient was consistent with the patient's primary cancer. At 3 months follow-up, the neurological condition of the patient was unchanged. CONCLUSIONS: This is the first reported case of ISCM from a primary ACC of the EAC.

4.
J Biol Chem ; 276(49): 46196-203, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11579086

RESUMO

Acidocalcisomes are acidic calcium storage compartments described initially in trypanosomatid and apicomplexan parasites. In this work, we describe organelles with properties similar to acidocalcisomes in the green alga Chlamydomonas reinhardtii. Nigericin and NH(4)Cl released (45)Ca(2+) from preloaded permeabilized cells, suggesting the incorporation of a significant amount of this cation into an acidic compartment. X-ray microanalysis of the electron-dense vacuoles or polyphosphate bodies of C. reinhardtii showed large amounts of phosphorus, magnesium, calcium, and zinc. Immunofluorescence microscopy, using antisera raised against a peptide sequence of the vacuolar type proton pyrophosphatase (H(+)-PPase) of Arabidopsis thaliana which is conserved in the C. reinhardtii enzyme, indicated localization in the plasma membrane, in intracellular vacuoles, and the contractile vacuole where it colocalized with the vacuolar proton ATPase (V-H(+)-ATPase). Purification of the electron-dense vacuoles using iodixanol density gradients indicated a preferential localization of the H(+)-PPase and the V-H(+)-ATPase activities in addition to high concentrations of PP(i) and short and long chain polyphosphate, but lack of markers for mitochondria and chloroplasts. In isolated electron-dense vacuoles, PP(i)-driven proton translocation was stimulated by potassium ions and inhibited by the PP(i) analog aminomethylenediphosphonate. Potassium fluoride, imidodiphosphate, N,N'-dicyclohexylcarbodiimide, and N-ethylmaleimide also inhibited PP(i) hydrolysis in the isolated organelles in a dose-dependent manner. These results indicate that the electron-dense vacuoles of C. reinhardtii are very similar to acidocalcisomes with regard to their chemical composition and the presence of proton pumps. Polyphosphate was also localized to the contractile vacuole by 4',6-diamidino-2-phenylindole staining, suggesting, with the immunochemical data, a link between these organelles and the acidocalcisomes.


Assuntos
Ácidos/metabolismo , Cálcio/metabolismo , Chlamydomonas reinhardtii/metabolismo , Pirofosfatases/metabolismo , Sequência de Aminoácidos , Animais , Chlamydomonas reinhardtii/enzimologia , Chlamydomonas reinhardtii/ultraestrutura , Microanálise por Sonda Eletrônica , Inibidores Enzimáticos/farmacologia , Microscopia Eletrônica , Microscopia de Fluorescência , Dados de Sequência Molecular , Mutagênese Insercional , Bombas de Próton/metabolismo , Pirofosfatases/antagonistas & inibidores , Pirofosfatases/química , Homologia de Sequência de Aminoácidos
5.
Biochem J ; 347 Pt 1: 243-53, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10727425

RESUMO

Plasmodium berghei trophozoites were loaded with the fluorescent calcium indicator, fura-2 acetoxymethyl ester, to measure their intracellular Ca(2+) concentration ([Ca(2+)](i)). [Ca(2+)](i) was increased in the presence of the sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase inhibitor, thapsigargin. Trophozoites also possess a significant amount of Ca(2+) stored in an acidic compartment. This was indicated by: (1) the increase in [Ca(2+)](i) induced by bafilomycin A(1), nigericin, monensin, or the weak base, NH(4)Cl, in the nominal absence of extracellular Ca(2+), and (2) the effect of ionomycin, which cannot take Ca(2+) out of acidic organelles and was more effective after alkalinization of this compartment by addition of bafilomycin A(1), nigericin, monensin, or NH(4)Cl. Inorganic PP(i) promoted the acidification of a subcellular compartment in cell homogenates of trophozoites. The proton gradient driven by PP(i) collapsed by addition of the K(+)/H(+) exchanger, nigericin, and eliminated by the PP(i) analogue, aminomethylenediphosphonate (AMDP). Both PP(i) hydrolysis and proton transport were dependent upon K(+), and Na(+) caused partial inhibition of these activities. PP(i) hydrolysis was sensitive in a dose-dependent manner to AMDP, imidodiphosphate, sodium fluoride, dicyclohexylcarbodi-imide and to the thiol reagent, N-ethylmaleimide. Immunofluorescence microscopy using antibodies raised against conserved peptide sequences of a plant vacuolar pyrophosphatase (V-H(+)-PPase) suggested that the proton pyrophosphatase is located in intracellular vacuoles and the plasma membrane of trophozoites. AMDP caused an increase in [Ca(2+)](i) in the nominal absence of extracellular Ca(2+). Ionomycin was more effective in releasing Ca(2+) from this acidic intracellular compartment after treatment of the cells with AMDP. Taken together, these results suggest the presence in malaria parasites of acidocalcisomes with similar characteristics to those described in trypanosomatids and Toxoplasma gondii, and the colocalization of the V-H(+)-PPase and V-H(+)-ATPase in these organelles.


Assuntos
Eritrócitos/parasitologia , Macrolídeos , Organelas/enzimologia , Plasmodium berghei/metabolismo , Pirofosfatases/metabolismo , Vacúolos/enzimologia , Cloreto de Amônio/farmacologia , Animais , Antibacterianos/farmacologia , Cálcio/farmacologia , Ácido Egtázico/farmacologia , Pirofosfatase Inorgânica , Ionomicina/farmacologia , Cinética , Malária/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monensin/farmacologia , Nigericina/farmacologia , Plasmodium berghei/efeitos dos fármacos , Bombas de Próton/metabolismo , Tapsigargina/farmacologia
6.
FEBS Lett ; 460(2): 217-20, 1999 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-10544238

RESUMO

Inorganic pyrophosphate promoted the acidification of a subcellular compartment in cell homogenates of Plasmodium falciparum trophozoites. The proton gradient driven by pyrophosphate was collapsed by addition of NH(4)Cl or the K(+)/H(+) exchanger nigericin and eliminated by the pyrophosphate analog aminomethylenediphosphonate. Pyrophosphatase activity was dependent upon K(+), and partially inhibited by Na(+). The presence of a plant-like vacuolar H(+)-translocating pyrophosphatase (V-H(+)-PPase) was confirmed using antibodies raised against conserved peptide sequences of the enzyme, which cross reacted with a protein band of 76.5 kDa. Immunofluorescence microscopy using these antibodies showed a general fluorescence over the whole parasites and intracellular bright spots suggesting a vesicular and plasma membrane localization. Together, these results indicate the presence in P. falciparum of a V-H(+)-PPase of similar characteristics to those of the enzyme from plants.


Assuntos
Plasmodium falciparum/enzimologia , Pirofosfatases/metabolismo , Vacúolos/enzimologia , Animais , Western Blotting , Hidrólise , Pirofosfatase Inorgânica , Microscopia de Fluorescência , Plantas/enzimologia , Prótons
7.
FEBS Lett ; 436(3): 377-81, 1998 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-9801152

RESUMO

This work provides evidence that phosphatidic acid (PA) is metabolized to diacylglycerol pyrophosphate (DGPP) in Trypanosoma cruzi. Also the presence of the enzymatic activities involved in its regulation, phosphatidate kinase (PA-k) and phosphatidate phosphatase, is demonstrated. The increase of DGPP levels in T. cruzi epimastigotes or in its membrane fraction after exogenous PA addition or phospholipase (PLD) pre-treatment suggests that PA-k may be involved in the regulation of PA levels after its stimulation.


Assuntos
Fosfatidato Fosfatase/metabolismo , Ácidos Fosfatídicos/metabolismo , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Trypanosoma cruzi/metabolismo , Animais , Membrana Celular/metabolismo , Cinética
8.
Acta Gastroenterol Latinoam ; 27(5): 331-4, 1997.
Artigo em Espanhol | MEDLINE | ID: mdl-9460514

RESUMO

UNLABELLED: The severity and/or the prognostic of infections with the hepatitis A virus (HAV) is related to the age at which the infection occurs. Since transmission of the virus occurs by the fecal-oral route, the prevalence and age-relate incidence of infection is determined by the adequacy of sanitation hygienic measures and the socio economic level of exposed populations. Thus, the disease is having an increasing impact in developing countries with improving sanitary standards whereas inhabitants of industrialized countries are particularly at risk while visiting under-developed countries. We have established a cooperative group for the serologic study of children range between six months to ten years old, without sintomatology of acute hepatitis. The patients live in Buenos Aires, San Justo, Trelew, Rosario and Tucumán cities. We studied 3699 children. The specific Ab-antiHAV IgG were measured by enzyme immunoassay with commercial available kits (Organon and-or Abbott). The variable of study were age, sex and water quality. RESULTS: 45.19% were of San Justo, 26.15% of Rosario, 13% of Buenos Aires, 8.37% of Trelew and 7.29% of Tucumán. We observed the highest of possibility percentage (%POS) in Tucumán (81.4%), followed by San Justo (57.8%), Rosario (46.5%), Trelew (41.99%) and Buenos Aires (29.4%). In all the cities the lowest %POS was found in children under three years old. Between three and six years old the results were variable and an increase in %POS was observed related to the growth. The global %POS was 51.56%. CONCLUSIONS: This study confirms Argentina as a high endemic country for HAV infection. A global vaccination program is the only strategy that has the potential to prevent recurrent epidemics of hepatitis A and its erradication.


Assuntos
Doenças Endêmicas , Hepatite A/epidemiologia , Fatores Etários , Argentina/epidemiologia , Criança , Pré-Escolar , Doenças Endêmicas/prevenção & controle , Fatores Epidemiológicos , Feminino , Hepatite A/prevenção & controle , Humanos , Incidência , Lactente , Masculino , Projetos Piloto , Prevalência , Vacinas contra Hepatite Viral , Abastecimento de Água
9.
Acta gastroenterol. latinoam ; 27(5): 331-4, 1997. tab, graf
Artigo em Espanhol | LILACS | ID: lil-205080

RESUMO

Objetivos: Determinar la curva de infección del HAV en niños menores de diez años. Establecer estrategias de vacunación en la Argentina. Material y Métodos: se etableció un grupo cooperativo para el rastreo serológico de niños entre los seis meses y los diez años de edad, sin sintomatología y/o cuadro clínico de hepatitis aguda, tomando como grupo inicial de trabajo a Centros de las ciudades de Bs. As., San Justo (Pcia, de Bs. As.), Trelew (Chubut), Rosario (Santa Fe) y Tucumán. Se estudiaran 3699 niños para Anti-HAV-IgG por ELISA (Oragnon y Abbott). Las variables de inclusión fueron: edad, sexo y calidad de agua. Resultados: 45.19 por ciento de las muestras fueron de San Justo, 26.15 por ciento de Rosario, 13 por ciento de Buenos Aires, 7.29 por ciento de Tucumán y 8.37 por ciento de Trelew. 1) Se observó el mayor porcentaje de positividad (porcentajePOS) en Tucuman (81.4 por ciento) seguido por San Justo (57.8 por ciento) y Rosario (44.3 por ciento). 2) En todas las ciudades los menores porcentajePOS correspondieron a menores de tres años. 3) La mayor dispersión del porcentajePOS ocurre entre los tres y seis años de edad. 4) en todo el muestreo se observó un valor creciente de porcentajePOS con pendientes similares, excepto para Trelew, donde aparece un pico a los cuatro años atribuíble a las características de la muestra. 5) El porcentajePOS global para la muestra fue de 51.56 por ciento. Conclusiones: 1) Este trabajo demuestra que nuestro país es de alta endemicidad para la infección por HAV. 2) La vacunación a corta edad sería la estrategia más adecuada para el control de la hepatitis A y la erradicación de la infección por el HAV.


Assuntos
Feminino , Humanos , Lactente , Pré-Escolar , Criança , Doenças Endêmicas , Hepatite A , Fatores Etários , Argentina , Doenças Endêmicas , Fatores Epidemiológicos , Anticorpos Anti-Hepatite , Incidência , Projetos Piloto , Prevalência , Vacinas contra Hepatite Viral , Abastecimento de Água
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