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3.
Sci Rep ; 9(1): 13318, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527609

RESUMO

Nitrogen-vacancy (NV) centres in diamond hold promise in quantum sensing applications. A major interest in them is an enhancement of their sensitivity by the extension of the coherence time (T2). In this report, we experimentally generated more than four dressed states in a single NV centre in diamond based on Autler-Townes splitting (ATS). We also observed the extension of the coherence time to T2 ~ 1.5 ms which is more than two orders of magnitude longer than that of the undressed states. As an example of a quantum application using these results we propose a protocol of quantum sensing, which shows more than an order of magnitude enhancement in the sensitivity.

5.
J Phys Condens Matter ; 28(27): 275302, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27214571

RESUMO

Optically detected magnetic resonance (ODMR) is a way to characterize the ensemble of NV-centers. Recently, a remarkably sharp dip was observed in the ODMR with a high-density ensemble of NV centers. The model (Zhu et al 2014 Nat. Commun. 5 3424) indicated that such a dip was due to the spin-1 properties of the NV- centers. Here, we present many more details of the analysis to show how this model can be applied to investigate the properties of the NV- centers. By using our model, we have reproduced the ODMR with and without applied external magnetic fields. Additionally, we investigate how the ODMR is affected by the typical parameters of the ensemble NV- centers such as strain distributions, inhomogeneous magnetic fields, and homogeneous broadening width. Our model provides a way to characterize the NV- center from the ODMR, which would be crucial to realize diamond-based quantum information processing.

6.
Eur J Surg Oncol ; 40(7): 818-23, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24768416

RESUMO

PURPOSE: Upper extremity lymphedema (LE) is a harmful breast cancer complication. It has been reported that patient- or treatment-related risk factors of LE. Axillary reverse mapping (ARM) has been performed to prevent LE during axillary lymph node dissection (ALND) by visualizing the upper extremity lymphatics. We investigated whether ARM related factors included novel predictive risk factors of LE. METHODS: ARM revealed fluorescent axillary nodes (ARM nodes) in 76 patients by fluorescence imaging. Only ARM nodes within the ALND field were removed. Twenty-four (32%) patients developed LE (LE+) and 52 did not (LE-) during a median 24-month post-surgical follow-up period. We retrospectively evaluated the clinical features and ARM factors of LE+ and LE-. RESULTS: The positive ARM node rate among LE+ was 42%, significantly greater frequency than that among LE- (13%: p ≤ 0.05). Cranial collectors (lymphatic ducts along or above the axillary vein) were significantly more frequent in LE- (44%) than in LE+ (21%: p ≤ 0.05). Multivariate analysis revealed postoperative radiation and positive ARM nodes to be positive risk factors and cranial collectors to be a negative risk factor of LE. CONCLUSIONS: ARM factors could predict the incidence of LE post-axillary surgeries in breast cancer patients.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Linfonodos/patologia , Linfedema/etiologia , Mastectomia/efeitos adversos , Idoso , Axila/cirurgia , Biópsia por Agulha , Estudos de Coortes , Feminino , Fluorescência , Humanos , Imuno-Histoquímica , Excisão de Linfonodo/efeitos adversos , Excisão de Linfonodo/métodos , Linfonodos/cirurgia , Linfedema/fisiopatologia , Linfedema/cirurgia , Mastectomia/métodos , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Biópsia de Linfonodo Sentinela/efeitos adversos , Biópsia de Linfonodo Sentinela/métodos , Resultado do Tratamento , Extremidade Superior
7.
Acta Neurochir (Wien) ; 146(4): 329-35; discussion 335, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15057526

RESUMO

BACKGROUND: Surgery of vertebral artery-posterior inferior cerebellar artery (VA-PICA) aneurysms is not easy because there is a close anatomical relationship between aneurysms and the surrounding neurovascular structures, and bony structures in the lateral foramen magnum. The preoperative evaluation for a circumstantial comprehension of anatomical relationships is very important for the surgical treatment of the VA-PICA aneurysms. Our experience in using three-dimensional CT angiography (3D-CTA) for the surgical management of VA-PICA aneurysms is herein reported. METHODS AND FINDINGS: We successfully performed neck clipping in 5 cases of VA-PICA aneurysm using 3D-CTA. On 3D reconstructed images, we could see the characteristics of the aneurysms such as their relationships to the jugular tubercle and hypoglossal canal, the projecting direction of the dome, and the configuration of the neck in each case. 3D-CTA also provided a clear surgical view as well as the relationships of the aneurysms to the VA and origin of the PICA. Based on such information, we selected the most appropriate surgical approach among the transcondylar fossa approach, the transcondylar approach, or the far lateral approach with a C1 laminectomy. CONCLUSIONS: Since 3D-CTA demonstrates the surgical anatomy of VA-PICA aneurysms in detail, it is very useful for helping surgeons to select the optimal approach.


Assuntos
Angiografia/métodos , Cerebelo/irrigação sanguínea , Cerebelo/diagnóstico por imagem , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/patologia , Adulto , Idoso , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Pescoço/anatomia & histologia , Instrumentos Cirúrgicos , Tomografia Computadorizada por Raios X
8.
Pancreas ; 22(2): 214-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11249080

RESUMO

Pseudocysts and post-necrotic collections of the pancreas are sometimes treated by percutaneous drainage. In cases of post-necrotic collection, intractable pancreatic juice fistula is often formed by disruption of the main pancreatic duct in the necrotized region. We radically treated intractable pancreatic juice fistulae by selective cannulation into the distal pancreatic duct via the route for percutaneous drainage of post-necrotic collections to extinguish the exocrine function of the caudal pancreas. We performed this procedure in two patients in whom the major pancreatic duct was damaged at the body of the pancreas, which was extensively necrotic. Although mild symptoms of acute pancreatitis appeared in both patients after the first procedure, they recovered without severe side effects. Neither recurrence of pancreatic juice fistulae nor reduction of the glucose tolerance was caused by removing the exocrine function of the caudal pancreas in either patient 32 and 24 months after treatment, respectively. This method is an effective treatment modality with which to treat intractable pancreatic juice fistulae with damage of the main pancreatic duct.


Assuntos
Embolização Terapêutica , Ductos Pancreáticos , Fístula Pancreática/terapia , Adulto , Humanos , Masculino , Suco Pancreático
9.
Clin Neuropathol ; 18(2): 87-92, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10192704

RESUMO

We herein report a unique case of cerebral lymphoma which occurred after lymphocytic neuritis of cranial nerves causing Tolosa-Hunt syndrome and demonstrate the histological difference between these two diseases. A 70-year-old woman developed a sensory disturbance in the first and third divisions of the left trigeminal nerve and a left ocular movement disturbance five years before death. Although she was clinically diagnosed to have a schwannoma in the left cavernous sinus, a histologic examination verified a diffuse infiltration of T lymphocytes in the left trigeminal ganglion. Corticosteroid therapy was effective. Thereafter she demonstrated a disturbance of consciousness and dysphasia four years after surgery. A T1-weighted magnetic resonance image (MRI) disclosed high intensity lesions in both the basal ganglia and corpus callosum. She also showed progressive spastic paralysis. At autopsy a diagnosis of primary intracranial B-cell lymphoma was made. Although there was no invasion of the lymphoma cells into the left trigeminal nerves, a mild inflammatory infiltration of T cells still remained.


Assuntos
Neoplasias Encefálicas/patologia , Linfoma de Células B/patologia , Oftalmoplegia/terapia , Idoso , Anti-Inflamatórios/uso terapêutico , Terapia Combinada , Corticosterona/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Oftalmoplegia/patologia
10.
Neuroradiology ; 40(7): 435-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9730342

RESUMO

A 47-year-old woman, who 2.5 years previously had undergone resection of a malignant astrocytoma of the left temporal lobe followed by radiotherapy, was found to have a mass in the left frontal lobe. This showed high uptake of thallium-201 (201Tl) on single-photon emission computed tomography and 11C-methionine on positron-emission tomography, suggesting recurrent tumour. Histological examination of the resected lesion, however, revealed it to be radionecrosis. This case thus illustrates a diagnostic pitfall in the use of these investigations for distinguishing radionecrosis from recurrent malignant glioma.


Assuntos
Encefalopatias/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Lesões por Radiação/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão , Adulto , Astrocitoma/radioterapia , Encéfalo/efeitos da radiação , Encefalopatias/etiologia , Neoplasias Encefálicas/radioterapia , Radioisótopos de Carbono , Feminino , Humanos , Metionina , Compostos Radiofarmacêuticos , Lobo Temporal , Radioisótopos de Tálio , Fatores de Tempo
11.
Chem Pharm Bull (Tokyo) ; 45(11): 1805-13, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9396157

RESUMO

Several polyenylidene thiazolidine or 2-thioxo-4-thiazolidinone derivatives were synthesized and their retinoidal activities were examined in terms of the differentiation-inducing ability towards human promyelocytic leukemia HL-60 cells and inhibitory effect on interleukin (IL)-1 alpha-induced IL-6 production in MC3T3-E1 cells. Compounds containing a trimethylcyclohexenyl ring induced HL-60 cell differentiation with weaker activity than retinoic acid (1a) by one or two orders of magnitude. The thiazolidinedione derivatives (2, 5, 7) showed stronger activity than the corresponding 2-thioxo-4-thiazolidinone derivatives (3, 6, 8). The effects of a retinoid antagonist (LE540) and synergists (retinoid X receptor (RXR) agonists, HX600 or HX630) on the activities of thiazolidine derivatives indicate that these compounds elicit their activities through the nuclear retinoic acid receptors (RARs). All the thiazolidines examined also inhibited IL-1 alpha-induced IL-6 production with IC50 values of 10 nM order. The retinoidal activities of the thiazolidines are significant, considering that replacement of the carboxylic acid in retinoid structures with bioisosteric functional groups is generally ineffective, as seen in the structure-activity relationships of retinoidal benzoic acids.


Assuntos
Receptores do Ácido Retinoico/efeitos dos fármacos , Retinoides/síntese química , Tiadiazóis/síntese química , Diferenciação Celular/efeitos dos fármacos , Células HL-60 , Humanos , Interleucina-6/biossíntese , Espectroscopia de Ressonância Magnética , Retinoides/farmacologia , Relação Estrutura-Atividade , Tiadiazóis/farmacologia
12.
No Shinkei Geka ; 23(11): 985-9, 1995 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-7477721

RESUMO

The authors report a case of bacterial intracranial aneurysm associated with infective endocarditis. A 48-year-old male was admitted on March 26, 1994, with complaints of difficulty in speaking and mild swelling of the right leg following mild fever. On examination he showed motor aphasia and mild weakness of the right upper and lower limbs. Cardiac auscultation revealed a grade 3/6 holosystolic murmur. Laboratory data revealed signs of infection through white blood cell count and CRP. Enterococcus faecalis was isolated from the blood culture at the time of admission. A computerized tomographic (CT) scan and magnetic resonance (MR) imaging showed a round mass with perifocal edema. Angiography revealed an aneurysm from the precentral artery of the left middle cerebral artery. A mycotic aneurysm due to bacterial endocarditis was diagnosed. The patient was treated with high doses of antibiotics. However, angiography 2 weeks after the initial study demonstrated the enlargement of the aneurysm and severe narrowing of the angular artery. On April 19, excision of the aneurysm was performed. Operative findings showed degeneration and thickening of the walls of the aneurysm. After the operation, antibiotic therapy was continued. The patient was asymptomatic upon discharge and has continued to do well. Repeated angiography on September 12 showed no further aneurysm. There is a danger of rupture in mycotic aneurysm due to bacterial endocarditis. It is important to repeat angiography and to manage the primary disease. If an aneurysm enlarges with serial angiography, it should be treated surgically without further delay.


Assuntos
Aneurisma Infectado/etiologia , Endocardite Bacteriana/complicações , Enterococcus faecalis , Infecções por Bactérias Gram-Positivas/complicações , Aneurisma Intracraniano/etiologia , Aneurisma Infectado/diagnóstico por imagem , Aneurisma Infectado/patologia , Angiografia Cerebral , Enterococcus faecalis/isolamento & purificação , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade
14.
Surg Neurol ; 42(2): 117-20, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8091287

RESUMO

We describe two cases with malignant lymphoma presented as scalp tumors. Both patients had slowly growing subcutaneous lymphoma masses in the scalp after head trauma. In the first case, the scalp lymphoma presented as a recurrent disease during complete remission of her systemic lymphoma after chemotherapy. In the second case, the tumor involved the scalp, subjacent skull, and intracranial space without systemic manifestation. These cases represent examples of a possible relationship between head trauma and the development of between head trauma and the development of tumors involving the brain and its coverings.


Assuntos
Traumatismos Cranianos Fechados/complicações , Linfoma/etiologia , Couro Cabeludo , Neoplasias Cutâneas/etiologia , Idoso , Feminino , Humanos , Linfoma/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/patologia
15.
Masui ; 42(8): 1171-6, 1993 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-8366557

RESUMO

We have developed transdermally applicable 10% lidocaine aqueous gel containing an absorption promoter and applied it for 15 patients suffering from severe pain in acute or subacute phase of herpes zoster. The patients, consisting of 7 males and 8 females with a mean age 58.5 +/- 13.0 (SD) yrs, had skin eruptions of herpes zoster for the past 2 months. Lidocaine-gel was applied locally to the diseased skin with or without an occlusive dressing. In 14 of the 15 patients (93%), a remarkable reduction of pain (below 10% of pretreatment level) was obtained after 9.9 +/- 5.6 (SD) times of lidocaine-gel treatments. There was no adverse systemic reactions or local skin damages. None of them developed post-herpetic neuralgia. The lidocaine-gel treatment appears to be very useful for reduction of pain associated with acute or subacute phase of herpes zoster.


Assuntos
Herpes Zoster/fisiopatologia , Lidocaína/administração & dosagem , Dor/tratamento farmacológico , Administração Cutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Curativos Oclusivos , Absorção Cutânea
16.
Neurol Med Chir (Tokyo) ; 33(4): 205-11, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7685850

RESUMO

The expression of the B-chain of platelet-derived growth factor (PDGF) was analyzed in 29 human brain tumors (4 astrocytomas, 7 glioblastomas, 3 medulloblastomas, 3 oligodendrogliomas, 7 meningiomas, and others) using monoclonal antibody after digestion with alkaline phosphatase, and compared with proliferative activities measured by in vivo uptake of bromodeoxyuridine. Medulloblastomas contained the highest amounts of PDGF B-chain, some four to eight times more than that in control brain tissue. The most predominant PDGF molecule of the medulloblastoma was 17 kd. Astrocytomas, glioblastomas, oligodendrogliomas, and meningiomas contained predominantly 30 and/or 22-24 kd molecules. Glioblastoma and meningioma proliferative activities correlated closely to PDGF concentrations, with only a few exceptions. Tumors that contained a high level of PDGF B-chain showed high proliferative activity, while tumors with high proliferative activity did not always contain a high level of PDGF B-chain. Tumors that contain many PDGF B-chains may thus indicate malignancy.


Assuntos
Neoplasias Encefálicas/genética , Divisão Celular/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Fator de Crescimento Derivado de Plaquetas/genética , Proteínas Proto-Oncogênicas/genética , Adolescente , Adulto , Idoso , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Divisão Celular/fisiologia , Criança , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas c-sis
17.
Microbiol Immunol ; 35(2): 163-6, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1909414

RESUMO

Chemical inactivation of pathogen of Creutzfeldt-Jakob disease (CJD) was examined using the mouse-adapted CJD strain. A high concentration of formic acid, guanidine compounds, trichloroacetate and phenol prevented CJD transmission. NaOH between 0.25 and 2 N lengthened the incubation periods. Sodium dodecyl sulfate (SDS) in a concentration between 1 and 3% did not alter incubation at room temperature but did completely block the transmission after boiling for 3 min in 3% SDS. This method is recommended for practical disinfection.


Assuntos
Síndrome de Creutzfeldt-Jakob/microbiologia , Príons , Ativação Viral , Ácidos , Álcoois , Álcalis , Animais , Encéfalo/microbiologia , Modelos Animais de Doenças , Desinfecção , Feminino , Camundongos , Virulência
18.
Acta Neurochir Suppl (Wien) ; 53: 127-36, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1803869

RESUMO

We have experienced 29 cases of tumour in the pineal region and posterior third ventricle in the CT and MR eras (from 1976 to 1989). An aggressive surgical removal was performed except for germinomas and suspected germinomas. The aggressive surgical cases were 5 teratomas including one inclusion foetus, one yolk sac tumour, 3 astrocytomas, one neurocytoma, one cavernous haemangioma and one telangiectasia. The surgery was performed by either the infratentorial supracerebellar approach or the occipital transtentorial approach. There was no surgical death and the quality of postoperative survival was good in patients with benign tumours. The cases of a typical teratoma, teratoma with an arterio-venous shunt, inclusion foetus, haemorrhagic nodule of telangiectasia etc. are briefly presented. A remarkable progress in the diagnosis and surgical treatment of tumours in the pineal region in the CT and MR eras is noted in our results.


Assuntos
Neoplasias Encefálicas/cirurgia , Neoplasias do Ventrículo Cerebral/cirurgia , Imageamento por Ressonância Magnética , Glândula Pineal/cirurgia , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Neoplasias Encefálicas/diagnóstico , Angiografia Cerebral , Neoplasias do Ventrículo Cerebral/diagnóstico , Criança , Pré-Escolar , Terapia Combinada , Irradiação Craniana , Craniotomia/métodos , Feminino , Seguimentos , Humanos , Lactente , Masculino , Microcirurgia/métodos , Exame Neurológico , Glândula Pineal/patologia , Doenças Talâmicas/diagnóstico , Doenças Talâmicas/cirurgia
19.
Neurosurgery ; 27(2): 224-30, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2385340

RESUMO

The clinical and histopathological features of 19 patients with tumors involving the septum pellucidum are presented. These tumors predominantly affected young adults, and the clinical manifestations were usually the results of raised intracranial pressure related to obstructive hydrocephalus, mental abnormality, epileptic seizures, or a combination of these. Seventeen of the tumors grew mainly in the lateral and third ventricles, and the other 2 grew both into the lateral ventricle and the cerebral parenchyma. The direction of cellular differentiation of the tumor cells varied from patient to patient and consisted of 8 neurocytomas, 1 mature neuronal tumor with ganglionic and small round neuronal cells, 3 subependymomas, 3 subependymal giant cell astrocytomas, 2 pilocytic astrocytomas, 1 malignant astrocytoma, and 1 teratoma with embryonal carcinoma. These tumors were considered to have arisen from the multipotential cells in the subependymal plate or germ cell rests in the lateral ventricular wall, especially in the septum pellucidum. Because of the relatively inert biological behavior and histological features of most of these tumors, we favor the malformative theory of their origin. Either total or an extensive excision of the tumors in this series, which had developed mainly in the ventricular system, provided long-term survival in many cases.


Assuntos
Neoplasias Encefálicas/patologia , Septo Pelúcido/patologia , Adolescente , Adulto , Astrocitoma/patologia , Astrocitoma/terapia , Neoplasias Encefálicas/terapia , Criança , Feminino , Glioma/patologia , Glioma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Neuroblastoma/patologia , Neuroblastoma/terapia
20.
Neurosurgery ; 26(2): 332-5, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2308684

RESUMO

We report a case of aspergillosis in the subdural space and frontal lobe in an 83-year-old man. The clinical course simulated that of a brain tumor. The source for the infection was considered to be the previous burr-hole surgery for chronic subdural hematoma, which was performed 2.5 years before the onset of symptoms. The patient was treated by removal of the abscess and granuloma. The clinical features and treatment of aspergillosis after neurosurgical procedures are discussed.


Assuntos
Aspergilose/etiologia , Encefalopatias/microbiologia , Hematoma Subdural/cirurgia , Complicações Pós-Operatórias , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Flucitosina/uso terapêutico , Hematoma Subdural/complicações , Humanos , Masculino
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