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1.
RSC Adv ; 13(19): 12917-12924, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37114016

RESUMO

In this study, the crystallization behavior of polyvinylidene fluoride (PVDF) in NMP/DMF solvent at 9 to 67 weight percent (wt%) was analyzed by molecular dynamics (MD) simulation. The PVDF phase did not gradually change with the incremental increase in PVDF wt%, but displayed rapid shifts at 34 and 50 wt% in both solvents. The solvation behavior between the two solvents was quite identical from the similar radial distribution functions. However, PVDFs in DMF solvent showed a higher ratio of ß phase crystalline structures than those in NMP solvent. It was found that DMF solvents were more tightly packed near trans state PVDF fluorine compared to NMP solvents. Also, NMP oxygen atoms interacted more favorably with gauche state PVDF hydrogen atoms over DMF oxygen atoms. The evaluation of properties observed in atomic scale interactions, such as trans state inhibition and gauche state preference, can be used as indicators in future solvent research.

2.
J Spinal Cord Med ; 43(4): 548-551, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-29350608

RESUMO

Context: Scrub typhus is an acute febrile disease caused by Orientia tsutsugamushi. The disease can usually involve the lungs, heart, liver, spleen and brain through hematogenous dissemination. However, very rarely, acute transverse myelitis in the spinal cord develops from scrub typhus. We present a case of acute transverse myelitis following scrub typhus with a review of the literature. Findings: A 66-year-old male visited a hospital for general myalgia, mild headache, and fever in October. He was noted to have thick, black papule skin on his abdomen, which was highly suggestive of scrub typhus. To confirm the diagnosis, O. tsutsugamushi antibody titers were examined and detected highly in serum by an indirect fluorescence antibody assay. Doxycycline, the standard treatment for scrub typhus, was administered. However, after seven days of treatment, he rapidly developed weakness in the right leg, paresthesia in both lower limbs, and voiding difficulty. Spinal magnetic resonance imaging (MRI) revealed lesions with high signal intensity involving the spinal cord at the thoracolumbar junction. Paraparesis gradually improved following steroid pulse therapy for five days. At one-year follow-up, he could walk without cane. Conclusions:Orientia tsutsugamushi causes scrub typhus, which can affect not only the brain, but also the spinal cord. Although acute transverse myelitis develops rarely from scrub typhus, this should be considered as differential diagnosis in patients of fever with neurological deficit in endemic areas.


Assuntos
Mielite Transversa , Orientia tsutsugamushi , Tifo por Ácaros , Traumatismos da Medula Espinal , Idoso , Humanos , Imageamento por Ressonância Magnética , Masculino , Mielite Transversa/diagnóstico , Mielite Transversa/etiologia , Tifo por Ácaros/complicações , Tifo por Ácaros/diagnóstico
3.
J Clin Neurosci ; 53: 48-54, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29685417

RESUMO

OBJECTIVE: To investigate the surgical results of percutaneous pedicle screw fixation (PPSF) after spinal canal decompression via a small laminectomy for the treatment of thoracolumbar burst fractures. METHOD: Twenty-seven patients underwent PPSF after spinal canal decompression via small laminectomies between April 2009 and April 2015. Inclusion criteria consisted of a single-level, closed, thoracolumbar burst fracture and neurological symptoms. Decompression was performed via a small laminectomy, followed by PPSF, including at the level of the fractured vertebra. Cobb angle, vertebral wedge angle, and vertebral body index were each measured from lateral radiographs before and after surgery, and at last follow-up. Neurological assessment was made using the Frankel grading system. RESULTS: The average follow-up period was 26 months. The preoperative average Cobb angle was 15.8°â€¯±â€¯6.6°, and significantly decreased to 6.5°â€¯±â€¯6.2° postoperatively (p < 0.001). Average Cobb angle at last follow-up increased slightly to 8.9°â€¯±â€¯6.9°, but this was not significant (p = 0.112). The preoperative average vertebral wedge angle was 20.6°â€¯±â€¯6.3°, and decreased significantly to 12.2°â€¯±â€¯6.2° postoperatively (p < 0.001). The vertebral body index significantly decreased from 0.58 ±â€¯0.11 to a postoperative value of 0.78 ±â€¯0.10 (p < 0.001). Clinically, no patient deteriorated subsequent to surgery. CONCLUSION: Percutaneous pedicle screw fixation after spinal canal decompression via small laminectomy provides significant kyphotic correction and improved neurological outcome while offering decreased surgical morbidity. This may be applied as an effective primary surgery in select patients with TLBFs with neurologic symptoms.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas da Coluna Vertebral/cirurgia , Adulto , Idoso , Descompressão Cirúrgica/métodos , Feminino , Fixação Interna de Fraturas/instrumentação , Humanos , Laminectomia/métodos , Vértebras Lombares/cirurgia , Pessoa de Meia-Idade , Parafusos Pediculares , Estudos Retrospectivos , Vértebras Torácicas/cirurgia
4.
Medicine (Baltimore) ; 97(10): e0009, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29517657

RESUMO

RATIONALE: In the treatment of noncontiguous lumbar burst fractures, there still remains controversy over proper surgical procedures. PATIENT CONCERNS: A 19-year-old female patient visited our hospital after fall down from 3 m high. DIAGNOSES: Initial neurologic examination revealed an incomplete spinal cord injury characterized by hypoesthesia and motor grade of 2 below the L2 segment. Lumbar computed tomography and magnetic resonance imaging demonstrated L2 and L5 burst fractures severely obliterating the spinal canal. INTERVENTIONS: She underwent emergent PSSPSF at L1-2-3 and L4-5-S1 following bilateral L1 and L4 laminotomy with reduction of bony fragments by tapping method. OUTCOMES: She was gradually recovered and able to walk with assistance two weeks after surgery. Removal of implants was performed at 12 months after surgery. Follow-up radiography showed well-preserved segmental motion and adequate decompressed spinal canal with fused fractured bony fragment. She returned to her normal daily activities without any neurologic deficits and pain. LESSONS: Noncontiguous burst fracture of the lumbar spine is an unusual injury. For the adequate management in patient with neurologic deficit, reduction of the fractured body and stabilization of vertebral column is necessary. It is also important to preserve the segmental motion in young age patients. From that point of view, temporary PSSPSF with spinal canal decompression is considered as minimal invasive surgery with significant low morbidity, providing stability with motion saving and good clinical outcome.


Assuntos
Descompressão Cirúrgica/métodos , Fixação Interna de Fraturas/métodos , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fraturas da Coluna Vertebral/cirurgia , Acidentes por Quedas , Parafusos Ósseos/efeitos adversos , Feminino , Humanos , Laminectomia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adulto Jovem
5.
J Clin Neurosci ; 47: 341-346, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29050891

RESUMO

INTRODUCTION: This study was designed to evaluate the clinical and radiologic results of stand-alone synthetic polyetheretherketone (PEEK) cages for two- or three-level anterior cervical discectomy and fusion (ACDF), with a focus on subsidence. MATERIALS AND METHODS: We retrospectively reviewed a total of 68 patients who underwent two- or three-level ACDF with a stand-alone PEEK cage between April 2005 and August 2016. Radiologic parameters were assessed on lateral radiographs, and fusion was assessed on computed tomography scans. For the evaluation of clinical outcomes, visual analogue scale, neck disability index, and modified Japanese Orthopedic Association scores were measured. RESULTS: Among the total of 68 patients with a total of 144 segments, ACDF at two and three levels was performed in 60 and 8 patients, respectively, with a mean follow-up duration of 27.6 months. The overall fusion rate was 81.3% (117 of 144 segments), and subsidence occurred in 63 segments (43.8%) at the last follow-up. There was no statistically significant difference between the subsidence group and the nonsubsidence group in terms of fusion rate, radiologic outcomes, and clinical outcomes (p > .05). CONCLUSION: Subsidence might be an inevitable course and only a radiologic phenomenon with no effect on the clinical and radiologic outcomes of the use of stand-alone cages.


Assuntos
Discotomia/instrumentação , Fusão Vertebral/instrumentação , Adulto , Idoso , Benzofenonas , Vértebras Cervicais/cirurgia , Discotomia/efeitos adversos , Discotomia/métodos , Feminino , Seguimentos , Humanos , Cetonas , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , Polímeros , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Resultado do Tratamento , Adulto Jovem
6.
J Clin Neurosci ; 44: 236-239, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28694042

RESUMO

Distal peripheral artery aneurysms in moyamoya disease (MMD) remain difficult to treat given their deep location, small size, and fragility. Here, we report two cases of choroidal artery aneurysms associated with MMD who were treated through direct clipping and coil embolization. Timing of aneurysm formation remains unclear, however, annual follow-up DSA for surveillance of hemodynamic status is necessary and prompt treatment of aneurysm should be performed when diagnosed. Moreover, choroidal artery aneurysms may benefit from endovascular coil embolization due to their characteristics.


Assuntos
Aneurisma Roto/diagnóstico , Embolização Terapêutica , Aneurisma Intracraniano/diagnóstico , Doença de Moyamoya/complicações , Adulto , Aneurisma Roto/etiologia , Aneurisma Roto/terapia , Feminino , Humanos , Aneurisma Intracraniano/etiologia , Aneurisma Intracraniano/terapia , Masculino
7.
World Neurosurg ; 102: 56-64, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28263930

RESUMO

OBJECTIVE: In patients with intracerebral hematoma (ICH), it is well known that brain atrophy occurs in the hemisphere ipsilateral to the hematoma. The present study aimed to investigate contralateral hemispheric volume changes in patients with ICH as well as related factors. METHODS: Of 112 patients with ICH who were surgically treated at our hospital between January 2011 and December 2015, 44 were included in the present study. We measured contralateral hemispheric brain areas in 3 planes of axial brain computed tomography images. We obtained the proportion of contralateral hemispheric parenchyma to the hemispheric intracranial area to adjust for individual differences in head size. We analyzed the relationship between various factors and volume changes in the contralateral hemisphere. RESULTS: The average volume percentages of preoperative and follow-up contralateral hemispheric parenchyma were 92.3% versus 88.8%, 90.3% versus 85.3%, and 86.9% versus 82.5% in the level of foramen of Monro, septum pellucidum, and lateral ventricle, respectively. These decreases were all statistically significant (paired t-test; P < 0.001). As far as the causes of these decreases, the presence of intraventricular hematoma was the most significant factor for a decrease (P = 0.006). Glasgow coma scale score on arrival, as well as, smoking were independent factors in a multivariate analysis (P = 0.016, 0.039). CONCLUSIONS: Contralateral parenchymal volumes were significantly decreased at the 3-month follow-up brain computed tomography scan. These findings may offer important clinical information on the remote brain injury of ICH.


Assuntos
Encéfalo/patologia , Hemorragia Cerebral/complicações , Lateralidade Funcional , Adulto , Fatores Etários , Idoso , Atrofia/etiologia , Encéfalo/diagnóstico por imagem , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
8.
Springerplus ; 5(1): 1398, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27610317

RESUMO

INTRODUCTION: Langerhans cell histiocytosis (LCH) occurs rarely in the spine of adults. The radiological findings usually resemble vertebral tumors. Etiology of LCH has not been clearly established yet. Therapeutic approaches are still controversial. We describe a case of LCH in an adult spine. CASE DESCRIPTION: A patient who presented with low back pain had an osteolytic lesion in the L1 vertebral body without neurological deficits, and fluoroscopy-guided needle biopsy of the L1 vertebral body was performed. The immunohistochemical diagnosis confirmed LCH. The patient was successfully treated with conservative methods. DISCUSSION: The choice of appropriate therapy is very important, with treatment options varying from watch-and to aggressive treatment. CONCLUSION: LCH is considered as a pediatric disease that is extremely rare in the spine of adults and should be include in the differential diagnosis of osteolytic vertebral lesions. Conservative treatment is best choice for a patient with LCH without neurological deficit or spinal instability.

9.
J Nanosci Nanotechnol ; 15(11): 8472-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26726537

RESUMO

Ruthenium (Ru) thin films were grown on thermally-grown SiO2 substrates by plasma enhanced atomic layer deposition (PEALD) using a sequential supply of a new betadiketonate Ru metallorganic precursor, dicarbonyl-bis(5-methyl-2,4-hexanediketonato) Ru(II) (C16H22O6Ru) with a high vapor pressure and NH3 plasma as a reactant at the substrate temperature ranging from 175 and 310 degrees C. A self-limited film growth was confirmed at the deposition temperature of 225 degrees C and the growth rate was 0.063 nm/cycle on the SiO2 substrate with very short number of incubation cycles (approximately 10 cycles). The resistivity of PEALD-Ru films was dependent on the microstructural features characterized by grain size and crystallinity, which could be controlled by varying the deposition temperature. Ru film with the resistivity of -20 µΩ-cm and high density of 11.5 g/cm3 was obtained at the deposition temperature as low as 225 degrees C. It formed polycrystalline structure with hexagonal-close-packed phase that was confirmed by X-ray diffractometry and transmission electronic microscopy analysis. Step coverage of PEALD-Ru film deposited with the optimum condition was good (-75%) at the very small-sized trench (aspect ratio: -4.5 and the top opening size of 25 nm).

10.
Br J Neurosurg ; 27(1): 74-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22827635

RESUMO

Anaplastic astrocytoma (AA) sometimes shows a rapid poor course like glioblastoma. In this study, we investigated the prognosis of AA with radiologic necrosis which is the representative radiologic finding of glioblastoma. From 1995 to 2010, we operated on 26 patients who were confirmed to have AA. The male:female ratio was 13:13, and the median age was 47.23 years. The mean follow-up period was 3 years. We analyzed the prognostic significance of radiologic necrosis with age, sex, KPS, tumour location, radiologic findings, extent of removal and radiation therapy oncology group recursive partitioning analysis (RTOG-RPA) classification. The median progression-free survival (PFS) was 0.5 (± 0.17) years and the median overall survival (OS) was 1.6 (± 0.40) years. In univariate analysis, the clinical variables of younger age (p = 0.030) and RTOG-RPA class III (p = 0.043) correlated with longer PFS, and KPS (p = 0.038), radiologic necrosis (p = 0.013) and the extent of removal (p = 0.041) correlated with OS. The median OS was 1.0 (± 0.21) year in AA with radiologic necrosis compared to AA without radiologic necrosis, which showed 2.1 (± 0.29) years median OS. On multivariate analysis, there was no statistically significant prognostic factor. However, Cox's regression model revealed that gross total removal was associated with a longer OS (hazard ratio = 0.136; 95% CI, 0.018 to 1.046; p = 0.055) compared to partial removal or biopsy. Gross total resection was associated with good prognosis, and AA with radiologic necrosis had poor prognosis like glioblastoma.


Assuntos
Astrocitoma/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/patologia , Glioblastoma/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Diagnóstico Diferencial , Intervalo Livre de Doença , Feminino , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/diagnóstico por imagem , Prognóstico , Radiografia , Resultado do Tratamento , Adulto Jovem
11.
J Korean Neurosurg Soc ; 49(1): 68-70, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21494368

RESUMO

Neuroblastoma is a common tumor of children. We report a patient with extensive calvarial metastases of a neuroblastoma as an initial presentation. A 2-year-old girl presented with a history of gradually increasing head size and fever. A brain CT showed a multilobulated, large, extra-axial tumor involving both frontotemporoparietal areas with a sunray-spiculated hyperostosis of the skull and marked contrast enhancement. A brain MRI demonstrated extensive calvarial lesions with simultaneous involvement of the orbits. A biopsy was performed and a ganglioneuroblastoma was diagnosed. On systemic evaluation, an enlarged abdominal mass was detected. After neo-adjuvant chemotherapy, most of the tumors disappeared except for a tumor in the left parietal area; there was a corresponding decrease in the circumference of the head. We performed surgery for the remnant mass. Intensive chemotherapy was administered and a bone marrow transplantation was performed. Adequate neo-adjuvant chemotherapy followed by surgery to the neuroblatoma with extensive metastases to the skull and orbit may be helpful.

12.
Immunopharmacol Immunotoxicol ; 25(3): 377-84, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19180800

RESUMO

Purple bamboo salt is a specially processed salt according to the traditional recipe using normal salt and bamboo. It has been used for the purpose of prevention and treatment of various diseases in Korea. We investigated the anti-inflammatory activity of purple bamboo salt by using human mast cell line (HMC-1). Purple bamboo salt (1 mg/mL) inhibited phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187-stimulated tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 secretion, by 67.04% +/- 0.08%, 68.01% +/- 1.85%, and 69.48% +/- 0.54%, respectively. In addition, the expression of TNF-alpha mRNA in HMC-1 cells was inhibited by purple bamboo salt under the same condition. When NaCl (1 mg/mL) was added, the secretion of TNF-alpha and IL-6 was also inhibited but the effect was markedly lower than purple bamboo salt. Our results suggest that purple bamboo salt importantly contributes to the prevention or treatment of inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Mastócitos/efeitos dos fármacos , Medicina Tradicional Coreana , Extratos Vegetais/farmacologia , Sasa , Cloreto de Sódio/farmacologia , Calcimicina/farmacologia , Cálcio/metabolismo , Linhagem Celular , Citocinas/genética , Relação Dose-Resposta a Droga , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Ionóforos/farmacologia , Mastócitos/imunologia , RNA Mensageiro/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
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