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1.
Dalton Trans ; 46(45): 15736-15745, 2017 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-29095448

RESUMO

Zinc borates are very important industrial materials with applications that include fire retardants and preservatives in wood. In this work, we report the preparation of three novel zinc borates: [Zn(NH3)3B4O5(OH)4]·H2O (ZB1), Zn3(H2B3O7)2·2NH3·4H2O (ZB2), and [Zn(NH3)4][B4O5(OH)4]·4H2O (ZB3). The solid phases were characterized by elemental analysis, X-ray diffraction, infrared and Raman spectroscopy, scanning electron microscopy and thermal analysis. The crystal structures of ZB1 (monoclinic, Cc, a = 12.1972(8), b = 7.8314(5), c = 12.1441(8) Å and ß = 107.404(5)°) and ZB3 (orthorhombic, Pbca, a = 15.0796(9), b = 11.8853(5) and c = 16.7606(8) Å) were determined. They are novel neutral Zn-polyborate complexes [Zn(NH3)3B4O5(OH)4] hydrate and [Zn(NH3)4][B4O5(OH)4] tetrahydrate salt, respectively. The complete assignment of infrared and Raman spectra was performed theoretically using DFT calculations. For ZB2 (obtained as a polycrystalline phase), powder X-ray diffraction confirmed a single phase and allowed the determination of the unit cell parameters and lattice type (rhombohedral, a = 36.78076 (6), c = 12.20052 (3) Å) with an expected formula Zn3(H2B3O7)2·2NH3·4H2O suggesting that this compound is a complex triborate. Furthermore, a low-cost scalable synthetic procedure for ZB1 starting from zinc oxide and boric acid in ammonia solution with a high yield is also reported.

2.
J Clin Neurosci ; 20(11): 1564-70, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23928039

RESUMO

Mesial temporal sclerosis (MTS) is the most frequent cause of drug resistant symptomatic partial epilepsy. The mechanism and genetic background of this unique pathology are not well understood. Aquaporins (AQP) are regulators of water homeostasis in the brain and are expressed in the human hippocampus. We explored the role of AQP genes in the pathogenetic mechanisms of MTS through an evaluation of gene expression in surgically removed human brain tissue. We analyzed AQP1 and 4 mRNA levels by quantitative real-time polymerase chain reaction and normalized to ABL and cyclophilin genes, followed by immunohistochemistry for AQP4. Relative expressions were calculated according to the delta Ct method and the results were compared using the Mann-Whitney U test. Brain specimens of 23 patients with epilepsy who had undergone surgery for MTS and seven control autopsy specimens were investigated. Clinical findings were concordant with previous studies and 61% of the patients were seizure-free in the postoperative period. AQP1 and 4 gene expression levels did not differ between MTS patients and control groups. Immunofluorescence analysis of AQP4 supported the expression results, showing no difference. Previous studies have reported contradictory results about the expression levels of AQP in MTS. To our knowledge, only one study has suggested upregulation whereas the other indicated downregulation of perivascular AQP4. Our study did not support these findings and may rule out the involvement of AQP in human MTS.


Assuntos
Aquaporina 1/biossíntese , Aquaporina 4/biossíntese , Epilepsia do Lobo Temporal/genética , Hipocampo/metabolismo , Adolescente , Adulto , Idade de Início , Aquaporina 1/análise , Aquaporina 1/genética , Aquaporina 4/análise , Aquaporina 4/genética , Criança , Pré-Escolar , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/patologia , Feminino , Hipocampo/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Esclerose/metabolismo , Esclerose/patologia , Transcriptoma , Adulto Jovem
3.
Clin Neuropathol ; 30(6): 318-23, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22011738

RESUMO

CONTEXT: Lymphocytic anterior hypophysitis in association with a pituitary adenoma was reported previously. In rare instance, inflammatory infiltration was confined to adenoma tissue itself, excluding anterior pituitary. CASE: The patient - a 27-year-old male - presented with visual field defect. Further examination revealed a pituitary mass with suprasellar extension. Hormonal evaluation indicated mild hyperprolactinemia (42 ng/ml, normal < 19). After transsphenoidal resection, a pituitary adenoma showing cytoplasmic immunoreactivity to prolactin was identified. Dense and diffuse lymphocytic infiltration was seen within the tumor. At 15th month, a second transsphenoidal operation was necessary because of rapid development of visual compromise and headache. Excised surgical specimen consistent with previously resected adenoma showed diffuse lymphocytic infiltration composed of B and T cells within the adenoma tissue again. CONCLUSION: Presence of dense, hypophysitis-like lymphocytic infiltration within pituitary adenoma tissue obtained by two consecutive operations may reflect an host-mediated immune reaction to tumor. This rare finding could be challenging in terms of differential diagnosis and follow-up course.


Assuntos
Doenças da Hipófise , Neoplasias Hipofisárias , Adenoma , Diagnóstico Diferencial , Humanos , Hipopituitarismo , Masculino
4.
J Nephrol ; 14(4): 304-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11506255

RESUMO

We report a case of a 35-year-old man with nocardiosis infection involving soft tissue and the central nervous system who had received a cadaveric donor kidney. The patient was admitted with fever, malaise and right shoulder pain. Soft tissue abscess was seen on ultrasound examination. It was presumed due to gram (+) microorganisms, so 4 g day (IV) ampicillin/sulbactam was started empirically once the abscess was drained. Nocardia asteroides was found in the pus specimen. On the second day in hospital, severe headache, ataxia and signs of meningeal irritation appeared. The cranial CT showed two intracranial abscesses in the frontal lobe and cerebellum. We assumed Nocardia asteroides was the infective agent for the cerebral abscesses, so antibiotic therapy was switched to trimethoprim-sulphamethox-asole (3x160/800 mg/d). Nausea and vomiting occurred on the fifth day of therapy, improving after drainage from the frontal abscess. However, these complaints recurred five days later. CT showed cerebellar abscess had become bigger. The patient's complaints improved after the second surgical drainage. N. asteroides was again grown in the aspiration fluids of both cerebral abscesses. Complete regression of the abscesses was seen in the CT after two months. Co-trimoxazole was continued for six months then withdrawn. Graft dysfunction was not observed. Early medical and surgical interventions may be life-saving in this potentially lethal disease.


Assuntos
Abscesso Encefálico/terapia , Doenças Cerebelares/terapia , Lobo Frontal , Transplante de Rim/efeitos adversos , Nocardiose/terapia , Infecções dos Tecidos Moles/terapia , Adulto , Terapia Combinada , Humanos , Masculino , Indução de Remissão , Índice de Gravidade de Doença
5.
Mov Disord ; 16(2): 306-10, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11295786

RESUMO

We report the safety results in nine patients with advanced idiopathic Parkinson's disease (PD) who underwent ablative surgery of unilateral subthalamic nucleus (STN). In eight patients, surgical objectives were attained without induction of abnormal involuntary movements or other adverse effects. One patient developed transient hemiballistic movements which improved within 2 weeks after surgery. Assessment at 2 weeks to 20 months postoperatively revealed no long-term adverse effects. We conclude that hemiballism following unilateral ablation of STN in patients with PD is a rare phenomenon, and unilateral ablative lesions of STN can be performed safely.


Assuntos
Discinesias/diagnóstico , Lateralidade Funcional/fisiologia , Doença de Parkinson/cirurgia , Complicações Pós-Operatórias , Núcleo Subtalâmico/cirurgia , Adulto , Idoso , Discinesias/epidemiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Doença de Parkinson/diagnóstico , Técnicas Estereotáxicas , Núcleo Subtalâmico/patologia , Tempo
6.
Minim Invasive Neurosurg ; 43(3): 163-70, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11108118

RESUMO

The results of a non-resective treatment approach for pineoblastoma comprising stereotactic biopsy, cerebrospinal fluid diversion, and fractionated radiotherapy in six patients over a period of six years are presented. There were three male and three female patients, with a median age at diagnosis of 20 years. Magnetic resonance imaging of the spine, ventricular cerebrospinal fluid cytology, and tumour markers in cerebrospinal fluid were negative. Tumour response to initial radiotherapy was complete in three patients and partial in three patients. Recurrences were treated with interstitial irradiation with iodine-125 seeds in four instances, repeat radiotherapy when time elapsed was more than five years in one instance, with surgical resection in two instances, and chemotherapy in two instances. The diagnostic and therapeutic effectiveness of this management strategy is assessed. There were no complications related to surgical procedures. The median follow-up time was 48 months (range 14-70 months). Five patients were alive at 14, 45, 51, 57, and 70 months of follow-up. One patient died of disease at 28 months following diagnosis. The overall survival rate was 80 % +/- 17.89 % at 28 months. The results of this study suggest that this non-resective treatment approach is acceptable as an initial treatment alternative to radical surgical resection of pineoblastomas.


Assuntos
Neoplasias Encefálicas/terapia , Glândula Pineal , Pinealoma/terapia , Adolescente , Adulto , Biópsia , Neoplasias Encefálicas/radioterapia , Derivações do Líquido Cefalorraquidiano , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Recidiva Local de Neoplasia , Pinealoma/radioterapia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ventriculostomia
7.
Acta Neurochir (Wien) ; 140(12): 1303-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9932133

RESUMO

Extraneural scarring is one of the factors negatively influencing the result of peripheral nerve surgery. Many organic materials have been used to prevent fibrosis. The effect of aprotinin on peripheral nerve scarring in rats was investigated in this study. Three types of surgical intervention were carried out; namely external neurolysis (I), abrasive injury (II), and anastomosis (III). The coded samples which consisted of pure collagen fibers soaked with aprotinin or phosphate-buffered saline were applied around the left sciatic nerves of rats whereas only sham operations were performed on the right sciatic nerves. Animals were sacrificed after 4 or 6 weeks. Neurological examination, gross evaluation of extraneural fibrosis, and histological study were undertaken. The results have demonstrated that aprotinin is a promising agent in the prevention of extraneural scarring.


Assuntos
Aprotinina/farmacologia , Cicatriz/prevenção & controle , Nervo Tibial/cirurgia , Animais , Fibrose , Masculino , Ratos , Ratos Sprague-Dawley , Valores de Referência , Nervo Tibial/patologia , Nervo Tibial/fisiopatologia
8.
Acta Neurochir (Wien) ; 138(10): 1246-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8955446

RESUMO

Modification of a type of end-to-side anastomosis that has been described before is studied. The recipient artery is occluded for only 3-4 minutes to complete the anastomosis by using only the running suture. The anastomotic site was studied by inspection and Scanning Electron Microscope (SEM) at different times after the operation on 30 rats.


Assuntos
Anastomose Cirúrgica/métodos , Artérias Carótidas/cirurgia , Revascularização Cerebral/métodos , Técnicas de Sutura , Animais , Artérias Carótidas/patologia , Masculino , Microscopia Eletrônica de Varredura , Ratos , Ratos Wistar , Cicatrização/fisiologia
9.
Surg Neurol ; 44(5): 479-81; discussion 481-2, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8629234

RESUMO

A left-sided L5-S1 lumbar disc herniation operation was performed on a 36-year-old woman in 1987. After a 6-year period, the same patient came back to the clinic with the problem of severe sciatic pain on the same side as before. Upon diagnosis, it was seen that the left S1 radix was compressed with a piece of free autofat graft in the foramen, which was used in the first operation. As far as the writers are informed, this is the first report about a later complication of epidural autofat graft in lumbar spine disc surgery.


Assuntos
Tecido Adiposo/transplante , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Complicações Pós-Operatórias/etiologia , Ciática/etiologia , Adulto , Feminino , Humanos
10.
J Neurosurg ; 76(2): 303-6, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1730961

RESUMO

A mass lesion of amyloid involving the central nervous system is a rare finding. A 64-year-old woman presented with a large amyloidoma at the skull base causing neural tissue compression. The only accompanying disease was an asymptomatic renal cyst. The mass had caused destruction of the bone elements and pathological calcification as seen on x-ray films, computerized tomography (CT) scans, and magnetic resonance (MR) images, and was enhanced after injection of contrast medium on both CT scans and MR imaging.


Assuntos
Amiloidose/complicações , Encefalopatias/etiologia , Síndromes de Compressão Nervosa/etiologia , Nervo Óptico , Crânio , Amiloidose/diagnóstico , Doenças Ósseas/complicações , Doenças Ósseas/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
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