Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 441
Filtrar
1.
J Phys Condens Matter ; 35(28)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37015243

RESUMO

We report the first study of electrical resistivity, magnetization, and specific heat on YbCo2. The measurements on a single-phased sample of YbCo2bring no evidence of magnetic ordering down to 0.3 K in a zero magnetic field. The manifestations of low Kondo temperature are observed. The specific heat value divided by temperature,C/T, keeps increasing logarithmically beyond 7 J/mol K2with decreasing temperature down to 0.3 K without no sign of magnetic ordering, suggesting a very large electronic specific heat. Analysis of the magnetic specific heat indicates that the large portion of the low-temperature specific heat is not explained simply by the low Kondo temperature but is due to the strong intersite magnetic correlation in both the 3dand 4felectrons. Temperature-dependent measurements under static magnetic fields up to 7 T are carried out, which show the evolution of field-induced transition above 2 T. The transition temperature increases with increasing field, pointing to a ferromagnetic character. The extrapolation of the transition temperature to zero field suggests that YbCo2is in the very proximity of the quantum critical point. These results indicate that in the unique case of YbCo2, the itinerant electron magnetism of Co 3d-electrons and the Kondo effect within the vicinity of quantum criticality of Yb 4f-local moments can both play a role.

2.
Neuropathol Appl Neurobiol ; 46(2): 111-124, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31179566

RESUMO

AIMS: Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown. METHODS: We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases. RESULTS: Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%). CONCLUSIONS: The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/imunologia , Linhagem da Célula/imunologia , Germinoma/diagnóstico , Germinoma/imunologia , Neoplasias Encefálicas/metabolismo , Perfilação da Expressão Gênica , Germinoma/metabolismo , Humanos , Prognóstico , Transcriptoma , Microambiente Tumoral/imunologia
3.
Transplant Proc ; 50(9): 2597-2600, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30401358

RESUMO

BACKGROUND: We have introduced and performed laparoscope-assisted surgery in living donor hepatectomy. The objective of this study was to investigate the long-term results of laparoscope-assisted living donor hepatectomy. METHODS: From 2006 to 2016, laparoscope-assisted living donor hepatectomy was performed in 11 patients (laparoscopic group), and conventional open living donor hepatectomy was performed in 40 patients (conventional group). Intraoperative and postoperative complications were evaluated according to the Clavien-Dindo classification and analyzed in the laparoscopic group for comparison with the conventional group. RESULTS: The median postoperative follow-up period was 88 months (range, 58-120 months) in the laparoscopic group. One donor in the conventional group died from a motor vehicle crash 16 months after surgery. All others were alive and returned to their preoperative activity level. Regarding intraoperative and early (≤90 days after surgery) postoperative complications, 1 patient (1/11, 9%) showed biliary fistula (Grade IIIa) in the laparoscopic group. In the conventional group, 6 patients (6/40, 15%) showed surgical complications of Grade I in 2 patients and Grade II in 4 patients. Regarding late (>90 days after surgery) postoperative complications, biliary stricture was observed in 1 patient of the laparoscopic group; this patient developed hepatolithiasis 6 years after surgery, and endoscopic lithotomy and extracorporeal shockwave lithotripsy were performed, resulting in successful treatment. Late complications were not observed in the conventional group. CONCLUSION: One donor in the laparoscopic group showed Grade IIIa late complications. The introduction of laparoscopic surgery to living donor hepatectomy should be performed carefully.


Assuntos
Hepatectomia/métodos , Laparoscopia/métodos , Doadores Vivos , Complicações Pós-Operatórias/epidemiologia , Adulto , Feminino , Seguimentos , Humanos , Laparoscopia/efeitos adversos , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Coleta de Tecidos e Órgãos/efeitos adversos
4.
Eur J Surg Oncol ; 43(4): 780-787, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28132788

RESUMO

BACKGROUND: This study sought to evaluate the prognostic heterogeneity of Stage III (Union for International Cancer Control, seventh edition) gallbladder carcinoma. METHODS: Of 175 patients enrolled with gallbladder carcinoma who underwent radical resection, 22 were classified with Stage IIIA disease (T3N0M0) and 46 with Stage IIIB disease (T2N1M0 [n = 23] and T3N1M0 [n = 23]). The median number of retrieved lymph nodes per patient was 18. RESULTS: This staging system failed to stratify outcomes between Stages IIIA and IIIB; survival after resection was better for patients with Stage IIIB disease than for patients with Stage IIIA disease, with 5-year survival of 54.9% and 41.0%, respectively (p = 0.366). Multivariate analysis for patients with Stage III disease revealed independently better survival for patients with T2N1M0 than for patients with T3N0M0 (p = 0.016) or T3N1M0 (p = 0.001), with 5-year survival of 77.0%, 41.0%, and 31.0%, respectively. When N1 status was subdivided according to the number of positive nodes, 5-year survival in patients with T2M0 with 1-2 positive nodes, T2M0 with ≥3 positive nodes, T3M0 with 1-2 positive nodes, and T3M0 with ≥3 positive nodes was 83.3%, 50.0%, 45.8%, and 0%, respectively (p < 0.001). CONCLUSIONS: The prognosis of T2N1M0 disease was better than that of T3N0/1M0 disease, suggesting that not all node-positive patients will have uniformly poor outcomes after resection of gallbladder carcinoma. T2M0 with 1-2 positive nodes leads to a favorable outcome after resection, whereas T3M0 with ≥3 positive nodes indicates a dismal prognosis.


Assuntos
Carcinoma/cirurgia , Colecistectomia/métodos , Neoplasias da Vesícula Biliar/cirurgia , Linfonodos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/mortalidade , Carcinoma/patologia , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Neoplasias da Vesícula Biliar/patologia , Humanos , Estimativa de Kaplan-Meier , Excisão de Linfonodo/métodos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida
6.
Transplant Proc ; 48(4): 1119-22, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27320570

RESUMO

BACKGROUND: Complete immune tolerance is the chief goal in organ transplantation. This study aimed to evaluate patients who successfully withdrew from immunosuppressive (IS) agents after living donor liver transplantation (LDLT). MATERIALS AND METHODS: A retrospective review of all adult LDLT from July 1999 to March 2012 was conducted. In patients who acquired immune tolerance after LDLT, their background and the course of surgical procedures were evaluated. RESULTS: Of a total of 101 adult LDLT patients, 8 patients were completely free of IS agents. Six of these patients (75%) were female, and the median age at the time of transplantation was 56 years (range, 31-66 years). The primary disease causing liver failure was type C liver cirrhosis (50%), fulminant hepatitis (25%), type B liver cirrhosis (12%), and alcoholic liver cirrhosis (12%). The median Child-Pugh score and MELD score were 13 points (range, 8-15 points) and 19 points (range, 10-18 points), respectively. The living related donor was the recipient's child (75%), sibling (12%), or parent (12%). ABO compatibility was identical in 62%, compatible in 25%, and incompatible in 12%. CONCLUSIONS: In this study, we evaluated the adult patients who successfully withdrew from IS agents after LDLT. In most cases, it took more than 5 years to reduce IS agents. Because monitoring of the serum transaminase level is not adequate to detect chronic liver fibrosis in immune tolerance cases, further study is required to find appropriate protocols for reducing IS agent use after LDLT.


Assuntos
Falência Hepática/imunologia , Falência Hepática/cirurgia , Transplante de Fígado , Tolerância ao Transplante , Adulto , Idoso , Esquema de Medicação , Feminino , Humanos , Imunossupressores/uso terapêutico , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
7.
Transplant Proc ; 48(4): 1212-4, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27320589

RESUMO

Endoscopic management of acute necrotic pancreatitis and walled off necrosis is less invasive than surgical treatment and has become the 1st choice for treating pancreatic necrosis and abscess. We treated a case of acute necrotic pancreatitis and walled off necrosis after auxiliary partial orthotopic living-donor liver transplantation (APOLT). A 24-year-old woman was admitted to our university hospital for removal of the internal biliary stent, which had already been placed endoscopically for the treatment of biliary stricture after APOLT. She had been treated for acute liver failure by APOLT 10 years before. After we removed the internal stent with the use of an endoscopic retrograde approach, she presented with severe abdominal pain and a high fever. Her diagnosis was severe acute pancreatitis after endoscopic retrograde cholangiography (ERC). Her symptoms worsened, and she had multiple organ failure. She was transferred to the intensive care unit (ICU). Immunosuppression was discontinued because infection treatment was necessary and the native liver had already recovered sufficiently. After she had been treated for 19 days in the ICU, she recovered from her multiple organ failure. However, abdominal computerized tomography demonstrated the formation of pancreatic walled off necrosis and an abscess on the 20th day after ERC. We performed endoscopic ultrasonography-guided abscess drainage and repeated endoscopic necrosectomy. The walled off necrosis diminished gradually in size, and the symptoms disappeared. The patient was discharged on the 87th day after ERC. This is the 1st report of a case of acute necrotic pancreatitis and walled off necrosis that was successfully treated by endoscopic management after APOLT.


Assuntos
Colangiografia , Remoção de Dispositivo , Endoscopia do Sistema Digestório/métodos , Transplante de Fígado , Pancreatite Necrosante Aguda/cirurgia , Complicações Pós-Operatórias/cirurgia , Stents , Procedimentos Cirúrgicos do Sistema Biliar , Gerenciamento Clínico , Drenagem/métodos , Feminino , Humanos , Insuficiência de Múltiplos Órgãos , Pancreatite Necrosante Aguda/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto Jovem
8.
Transplant Proc ; 48(4): 1215-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27320590

RESUMO

Surgical resection should be considered for isolated locally recurrent retroperitoneal liposarcomas. We experienced a case of successful re-resection for locally recurrent retroperitoneal liposarcomas 4 years after ex vivo tumor resection and autotransplantation of the liver. A 75-year-old man was admitted to our hospital. His diagnosis was local recurrence of liposarcomas. He had previously undergone ex vivo tumor resection and autologous orthotopic liver transplantation for a retroperitoneal tumor 4 years earlier. The resected tumor size was 23.5 × 15.5 × 12.5 cm. The tumor was revealed by means of histopathologic study to be a myxoid liposarcoma. Follow-up computerized tomography showed 2 recurrent tumors in the retropancreatic and para-aortic lesions. Although adhesion was severe within the operative field, we successfully performed complete en bloc re-resection of each recurrent tumor. The operative time was 250 minutes, and blood loss was 300 mL. The resected tumor sizes were 3.9 × 3.2 × 1.5 cm and 4.5 × 3.3 × 3.0 cm. The tumors were revealed by means of histopathologic study to be dedifferentiated liposarcomas. Postoperative complications included intestinal obstruction and colocutaneous fistula formation, both of which were treated surgically. The patient was discharged in an ambulatory state at 80 days after re-resection of the recurrent tumors. At the time of writing, he was alive with no evidence of recurrence, 14 months after re-resection and 62 months after primary ex vivo tumor resection. This is the first case of successful surgical re-resection for locally recurrent liposarcoma after ex vivo tumor resection and autotransplantation of the liver.


Assuntos
Lipossarcoma Mixoide/cirurgia , Lipossarcoma/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Recidiva Local de Neoplasia/cirurgia , Neoplasias Retroperitoneais/cirurgia , Transplante Autólogo/métodos , Idoso , Humanos , Lipossarcoma/diagnóstico por imagem , Lipossarcoma/patologia , Lipossarcoma Mixoide/diagnóstico por imagem , Lipossarcoma Mixoide/patologia , Masculino , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Duração da Cirurgia , Neoplasias Retroperitoneais/diagnóstico por imagem , Neoplasias Retroperitoneais/patologia , Tomografia Computadorizada por Raios X
9.
Transplant Proc ; 48(3): 988-90, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27234786

RESUMO

BACKGROUND: Long-term graft survival of partial pancreas auto-transplantation after total pancreatectomy has not been clarified. The clinical implications of repeat completion pancreatectomy for locally recurrent pancreatic carcinoma in the remnant pancreas after initial pancreatectomy also have not been clarified. METHODS: We have previously reported a 61-year-old woman presenting with re-sectable carcinoma of the remnant pancreas at 3 years after undergoing a pylorus-preserving pancreaticoduodenectomy for invasive ductal carcinoma of the pancreas head. We also performed distal pancreas auto-transplantation with the use of a part of the resected pancreas to preserve endocrine function. RESULTS: The patient was discharged at 20 days after surgery without any complications. She had been followed regularly in our outpatient clinic. She had been treated with S-1 as adjuvant chemotherapy; 72 months after the completion total pancreatectomy with distal partial pancreas auto-transplantation, the patient was alive without any evidence of the pancreatic carcinoma recurrence. The pancreas graft was still functioning with a blood glucose level of 112 mg/dL, HbA1C of 6.7%, and serum C-peptide of 1.2 ng/mL; and urinary C-peptide was 11.6 µg/d. CONCLUSIONS: Our patient demonstrated that repeated pancreatectomies can provide a chance for survival after a locally recurrent pancreatic carcinoma if the disease is limited to the remnant pancreas. An additional partial pancreas auto-transplantation was successfully performed to preserve endocrine function. However, the indications for pancreas auto-transplantation should be decided carefully in the context of pancreatic carcinoma recurrence.


Assuntos
Sobrevivência de Enxerto , Transplante de Pâncreas , Neoplasias Pancreáticas/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Transplante Heterotópico , Neoplasias Pancreáticas
10.
Urolithiasis ; 44(4): 299-310, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26721697

RESUMO

Several experimental and animal studies have demonstrated that substances rich in antioxidants can reduce the physicochemical and peroxidative risk factors for calcium oxalate (CaOx) renal stone formation in urine and blood. However, there are very few such investigations in humans. In the present pilot study, two varieties of tea, a green one from Japan (JGT) and a herbal one from South Africa (Rooibos) (RT), both rich in antioxidants, were administered to a group of CaOx stone formers (SF) (n = 8) for 30 days. Both teas were analysed for polyphenols by high-performance liquid chromatography and for minerals by plasma atomic and optical emission spectroscopy. 24 h urines (baseline and day 30) were analysed for lithogenic factors. CaOx metastable limits and crystal nucleation and growth kinetics were also determined in each urine sample. Deposited crystals were inspected by scanning electron microscopy. Blood samples were collected (baseline and day 30). Biomarkers of oxidative stress including plasma and urinary thiobarbituric acid reactive substances (TBARS) and urinary N-acetyl-ß-D-glucosaminidase (NAG) were also determined. Urinary physicochemical risk factors were also investigated after ingestion of RT for 30 days in two control groups (CG1 and CG2), the latter one of which consisted of habitual JGT drinkers. Statistical analyses were performed using Wilcoxon signed rank tests and Mann-Whitney tests for paired and independent measurements, respectively. Several flavonoids and catechins were quantified in RT and JGT, respectively, confirming that both teas are rich sources of antioxidants. Mineral content was found to be far below dietary reference intakes. There were no significant changes in any of the urinary physicochemical or peroxidative risk factors in the control groups or in SF, except for the supersaturation (SS) of brushite (Bru) which decreased in the latter group after ingestion of JGT. Crystal morphology showed a tendency to change from mixed CaOx mono- and di-hydrate to monohydrate after ingestion of each tea. Since the latter form has a stronger binding affinity for epithelial cells, this effect is not protective. Analysis of the physicochemical and peroxidative risk factors in CG1 and CG2 did not reveal any evidence of a synergistic effect between the two teas. Paradoxically, baseline risk factors in the habitual JGT control group were significantly raised relative to those in CG1. Our preliminary results suggest that ingestion of RT and JGT does not reduce the risk factors for CaOx stone formation in humans, but these findings need to be tested in further studies involving much larger sample sizes.


Assuntos
Antioxidantes/análise , Antioxidantes/uso terapêutico , Nefrolitíase/epidemiologia , Nefrolitíase/prevenção & controle , Chá/química , Chás de Ervas/análise , Adolescente , Adulto , Fenômenos Químicos , Humanos , Masculino , Oxirredução , Projetos Piloto , Fatores de Risco , Adulto Jovem
11.
Neuroscience ; 284: 217-224, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25286384

RESUMO

Orexins are bioactive peptides, which have been shown to play a pivotal role in vigilance state transitions: the loss of orexin-producing neurons (orexin neurons) leads to narcolepsy with cataplexy in the human. However, the effect of the need for sleep (i.e., sleep pressure) on orexin neurons remains largely unknown. Here, we found that immunostaining intensities of the α1 subunit of the GABAA receptor and neuroligin 2, which is involved in inhibitory synapse specialization, on orexin neurons of mouse brain were significantly increased by 6-h sleep deprivation. In contrast, we noted that immunostaining intensities of the α2, γ2, and ß2/3 subunits of the GABAA receptor and Huntingtin-associated protein 1, which is involved in GABAAR trafficking, were not changed by 6-h sleep deprivation. Using a slice patch recording, orexin neurons demonstrated increased sensitivity to a GABAA receptor agonist together with synaptic plasticity changes after sleep deprivation when compared with an ad lib sleep condition. In summary, the GABAergic input property of orexin neurons responds rapidly to sleep deprivation. This molecular response of orexin neurons may thus play a role in the changes that accompany the need for sleep following prolonged wakefulness, in particular the decreased probability of a transition to wakefulness once recovery sleep has begun.


Assuntos
Encéfalo/patologia , Regulação da Expressão Gênica/fisiologia , Neurônios/fisiologia , Orexinas/metabolismo , Receptores de GABA-A/metabolismo , Privação do Sono/patologia , Animais , Moléculas de Adesão Celular Neuronais/metabolismo , Relação Dose-Resposta a Droga , GABAérgicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Técnicas In Vitro , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/genética , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Orexinas/genética , Técnicas de Patch-Clamp , Privação do Sono/fisiopatologia , Vigília/fisiologia
12.
J Clin Neurosci ; 22(1): 69-72, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25443084

RESUMO

We present our experience with elective microsurgical clipping of unruptured intracranial aneurysms (UIA) and analyze this management. A total of 150 patients with UIA were reviewed and data were collected with regard to age, sex, presence of symptoms, location and size of the aneurysms, surgical complications and postoperative 1 year outcomes. Aneurysm size was assessed either by three-dimensional CT angiography or digital subtraction angiogram. Glasgow Outcome Scale was used to assess clinical outcomes. One hundred and fifty patients with 165 aneurysms were treated in this series. The mean size of the UIA was 5.6mm. Eighty aneurysms (48.5%) were less than 5mm in size, and 73 (44.2%) were from 5 to 10mm. Ten (6.1%) of the aneurysms were large and two (1.2%) were giant. One hundred and forty-three were asymptomatic and seven were symptomatic before surgery. The outcome was good in 147 patients (98%), and only three patients (2%) had a treatment-related unfavorable outcome. Five patients experienced transient neurological deficits and one patient experienced permanent neurological deficits. Overall 98.7% of the treated aneurysms were satisfactorily obliterated. Wound complications were seen only in three patients. In conclusion, UIA pose a significant challenge for neurosurgeons, where a delicate balance between benefits and possible risks must be weighed. If the requisite expertise is available, they can be treated surgically with low morbidity and a good outcome at specialized neurovascular centers.


Assuntos
Aneurisma Intracraniano/cirurgia , Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Resultado do Tratamento
13.
Clin Neuroradiol ; 24(2): 145-50, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23913018

RESUMO

PURPOSE: Many epidemiological studies on unruptured cerebral aneurysms have reported that the larger the aneurysm, the higher the risk of rupture. However, many ruptured aneurysms are not large. Electrocardiography (ECG)-gated 3D-computed tomography angiography (4D-CTA) was used to detect pulsation in unruptured cerebral aneurysms. The differences in the clinical course of patients in whom pulsation was or was not detected were then evaluated. METHODS: Forty-two patients with 62 unruptured cystiform cerebral aneurysms who underwent 4D-CTA and follow-up 3D-CTA more than 120 days later were studied. The tube voltage, tube current, and rotation speed were 120 kV, 270 mA, and 0.35 s/rot., respectively. ECG-gated reconstruction was performed, with the cardiac cycle divided into 20 phases. Patients with heart rates higher than 80 bpm were excluded, so 37 patients with 56 aneurysms were analyzed. RESULTS: Pulsation was detected in 20 of the 56 unruptured aneurysms. Of these 20 aneurysms, 6 showed a change in shape at the time of follow-up. Of the 36 aneurysms in which pulsation was not detected, 2 showed a change in shape at follow-up. There was no significant difference in the follow-up interval between the two groups. The aneurysms in which pulsation was detected were significantly more likely to show a change in shape (P = 0.04), with a higher odds ratio of 7.286. CONCLUSION: Unruptured aneurysms in which pulsation was detected by 4D-CTA were more likely to show a change in shape at follow-up, suggesting that 4D-CTA may be useful for identifying aneurysms with a higher risk of rupture.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/métodos , Angiografia Cerebral/métodos , Tomografia Computadorizada Quadridimensional/métodos , Frequência Cardíaca , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Fluxo Pulsátil , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma Roto/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Prognóstico , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade
14.
Rev Sci Instrum ; 83(8): 083112, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22938279

RESUMO

We have developed a quick-scanning x-ray absorption fine structure (QXAFS) system and installed it at the recently constructed synchrotron radiation beamline BL33XU at the SPring-8. Rapid acquisition of high-quality QXAFS data was realized by combining a servo-motor-driven Si channel-cut monochromator with a tapered undulator. Two tandemly aligned monochromators with channel-cut Si(111) and Si(220) crystals covered energy ranges of 4.0-28.2 keV and 6.6-46.0 keV, respectively. The system allows the users to adjust instantly the energy ranges of scans, the starting angles of oscillations, and the frequencies. The channel-cut crystals are cooled with liquid nitrogen to enable them to withstand the high heat load from the undulator radiation. Deformation of the reflecting planes is reduced by clamping each crystal with two cooling blocks. Performance tests at the Cu K-edge demonstrated sufficiently high data quality for x-ray absorption near-edge structure and extended x-ray absorption fine-structure analyses with temporal resolutions of up to 10 and 25 ms, respectively.

15.
J Clin Neurosci ; 18(8): 1097-100, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21715173

RESUMO

We present our preliminary experience with intraoperative near-infrared indocyanine green-videoangiography (ICG-VA) and analysis of blood flow dynamics using fluorescence intensity assessment in cerebral aneurysm clipping surgery. Thirty-nine patients with 43 intracranial aneurysms underwent microsurgical clipping. Intraoperative ICG-VA was performed before and after clip application. An infrared fluorescence module integrated into a surgical microscope was used to visualize fluorescence in the surgical field and we recorded the emitted fluorescent light. An integrated analytical visualization tool simultaneously analyzed the video sequence and converted it into an intensity diagram, which allowed an objective evaluation of the results rather than the subjective assessment of fluorescence using ICG-VA. Overall, ICG-VA was performed 137 times. Incomplete clipping was detected in four patients, which allowed suitable adjustment to completely obliterate the aneurysm. In 12 patients, perforators arising close to, or from, the aneurysmal neck were identified in the surgical field. In three patients, the ICG-VA intensity diagram provided valuable information leading to modification of the primary surgical maneuver. ICG-VA provides high resolution images allowing real-time assessment of the blood flow in the parent artery and arterial branches, including the perforators. The intensity diagram is useful for providing a more objective record of the hemodynamics than the traditional ICG-VA, which relies more on subjective assessment and may allow interobserver variability. We conclude that ICG-VA, combined with the intensity diagram, can reduce the morbidity and complications associated with aneurysm clipping and improve patient outcomes.


Assuntos
Angiografia Cerebral/métodos , Verde de Indocianina , Aneurisma Intracraniano/diagnóstico , Monitorização Intraoperatória/métodos , Adulto , Idoso , Feminino , Humanos , Raios Infravermelhos , Aneurisma Intracraniano/cirurgia , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/patologia , Artéria Cerebral Média/cirurgia , Estudos Retrospectivos , Gravação de Videodisco/métodos
16.
Interv Neuroradiol ; 17(2): 154-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21696652

RESUMO

This study compared digital measurement of aneurysm volume by 3D rotational angiography (3D-RA) with an approximation technique using three diameters of an aneurysm to re-interpret previously reported optimal packing densities (volume embolization ratio, VER) in coil embolization of intracranial aneurysms. Estimation of the volume of saccular aneurysms is important for calculation of the VER, which is in turn reported to be useful for prediction of coil compaction. The conventional formula for the volume estimation is V=4/3 π(A/2) (B/2) (C/2), where A, B, and C are the aneurysmal height, length, and width measured on 3D-RA image respectively. Using 3D rotational angiography data from 74 aneurysms, the approximated volume generated using the conventional formula was directly compared with the digitally measured volume. The digitally measured volume varied from 0.003 ml to 7.935 ml, and the dome-to-neck ratio (D/N) from 0.79 up to 4.62. We found that the conventional formula almost systematically underestimated the volume by up to 50 %, particularly when the neck was large relative to the dome (D/N<2). On average, digitally measured volume was 1.26~1.29 times larger than the approximated volume obtained using the conventional formula.Conventional 2D angiography based aneurysm volume calculation tends to underestimate an aneurysm volume, so the so-called VER (volume embolization ratio) could be overestimated.


Assuntos
Angiografia Cerebral/métodos , Imageamento Tridimensional/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Modelos Cardiovasculares , Índice de Gravidade de Doença , Humanos
17.
Surg Neurol Int ; 2: 42, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21541008

RESUMO

OBJECTIVE: To evaluate the usefulness and limitations of the intraoperative near-infrared (NIR) indocyanine green videoangiography (ICG-VA) and analysis of fluorescence intensity in cerebrovascular surgery. METHODS: Forty-eight patients received ICG-VA during various surgical procedures from May 2010 to August 2010. Included among them were 45 cases of cerebral aneurysms and 3 cases of cerebral arteriovenous malformations (AVMs). The infrared fluorescence module integrated into the surgical microscope was used to visualize fluorescent areas in the surgical field. An integrated analytical visualization tool constantly analyzed the fluorescence video sequence and generated it in the form of an intensity diagram for objective interpretation. RESULTS: Overall, the procedure of ICG VA was done 158 times in 48 patients. There was no adverse effect of ICG dye. In cerebral aneurysm cases, the images obtained were of high resolution. In 4 cases, incomplete clipping was detected by ICG-VA and allowed suitable adjustment to completely obliterate the aneurysm. In 3 aneurysm cases, the intensity diagram of ICG VA provided valuable information. ICG-VA identified the feeding arteries, the draining veins, and nidus in all 3 AVM cases, which was confirmed by an immediate analysis of fluorescence intensity. CONCLUSIONS: ICG-VA provides high resolution images allowing real-time assessment of the blood flow in surgical field. The intensity analysis function, in addition, is a useful adjunct to improve the accuracy of the clipping and decrease the complication rates in cerebral aneurysm cases. In cerebral AVM cases, with the help of color map and intensity diagram function, the superficial feeders, drainers, and nidus can be identified easily.

18.
Minim Invasive Neurosurg ; 53(5-6): 243-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21302192

RESUMO

OBJECTIVE: There are various options for the treatment of vertebral artery dissection aneurysms (VADA). Treatment with stents may be an effective method to treat VADA involving the posterior inferior cerebellar artery (PICA) and dissection of the dominant vertebral artery (VA). In this article, our personal experience of the treatment of VADAs by using stents and coils is reported. METHODS: Since 1998, 26 cases of VADA have been treated by endovascular surgery by the first author. Of these cases, 6 cases were treated using stents, 3 of which were treated using stent and coils, 2 patients were treated using double overlapping stents, and the remaining one patient was treated using a single stent. RESULTS: In all patients, dissection aneurysms were successfully covered by stents. There was one complication: an intraprocedural rupture during additional coil insertion without neurological deterioration. Follow-up angiography was performed in all 5 surviving patients except for one patient who died due to the severity of his original subarachnoid hemorrhage (mean duration of follow-up angiography 22.8 months, range 15-57 months). Total or subtotal disappearance of the VADA was achieved in all 5 cases. At one year after the treatment, all 5 surviving patients remained clinically stable without any neurological deficit. CONCLUSIONS: Treatment using stents is an effective alternative for the treatment of VA dissecting aneurysms, especially for lesions of the dominant VA or involving the PICA. However, additional coil insertion should be performed very carefully and may be avoided if stagnation of contrast material is achieved after overlapping stenting.


Assuntos
Embolização Terapêutica/instrumentação , Procedimentos Endovasculares/instrumentação , Dissecação da Artéria Vertebral/cirurgia , Artéria Vertebral/cirurgia , Adulto , Idoso , Angiografia Cerebral , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Resultado do Tratamento , Artéria Vertebral/diagnóstico por imagem , Dissecação da Artéria Vertebral/diagnóstico por imagem
19.
AJNR Am J Neuroradiol ; 30(7): 1451-3, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19279278

RESUMO

SUMMARY: We present 3 cases of extracranial head and neck schwannomas exhibiting fluid-fluid levels. In the described cases, CT and MR imaging showed predominantly cystic components, intermixed with cellular components. Histopathologic examinations of excised specimens revealed hemosiderin deposition, reflecting intratumoral hemorrhages, which was presumably a cause of fluid-fluid levels. Although fluid-fluid levels are nonspecific findings, schwannoma should be considered when radiologic images demonstrate marked cystic formation with fluid-fluid levels in extracranial head and neck tumors.


Assuntos
Líquido Cístico/citologia , Líquido Cístico/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico , Imageamento por Ressonância Magnética/métodos , Neurilemoma/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Regul Toxicol Pharmacol ; 54(3): 214-20, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19328216

RESUMO

The safety of LP20 and its prototype, a powder, with potential use in food, produced from a mixture of dextrin and heat-killed Lactobacillus plantarum L-137, was assessed in an acute study in mice, and in an in vitro bacterial reverse mutation assay, an in vitro chromosome aberration assay, and an in vivo mouse micronucleus assay. LP20 prototype was not acutely toxic when administered to male and female Slc:ICR mice by single gavage at 2000mg/kg bw. Dosing was not associated with mortality, clinical signs, changes in bodyweight, or macroscopic abnormalities. The LD(50) in mice was greater than 2000mg/kg bw. There was no evidence of genotoxicity of LP20 in the Ames assay (0-5000microg/plate) or in the in vitro chromosome aberration assay with Chinese hamster lung fibroblasts (0-5000microg/mL). Administration of two consecutive daily doses of 500, 1000, or 2000mg/kg bw by gavage to male Crlj:CD-1 mice was not associated with an increased incidence of micronuclei and did not alter the ratio of polychromatic to normochromatic erythrocytes. These studies show that LP20 powder is not acutely toxic and is without genotoxic activity both in vitro and in vivo.


Assuntos
Aditivos Alimentares/toxicidade , Lactobacillus plantarum , Animais , Cricetinae , Feminino , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Mutagenicidade , Testes de Toxicidade Aguda
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...