RESUMO
Intense ultrashort light pulses induce three dimensional localized phase transformation of diamond. Photoinduced amorphous structures have electrical conducting properties of a maximum of 64 S/m based on a localized transition from sp(3) to sp(2) in diamond. The laser parameters of fluence and scanning speed affect the resultant electrical conductivities due to recrystallization and multi-filamentation phenomena. We demonstrate that the laser-processed diamond with the periodic cylinder arrays have the characteristic transmission properties in terahertz region, which are good agreement with theoretical calculations. The fabricated periodic structures act as metallo-dielectric photonic crystal.
Assuntos
Diamante , Condutividade Elétrica , Cristalização , Cristalografia , Cinética , Lasers , Luz , Modelos Teóricos , Nanotubos de Carbono , Distribuição Normal , Óptica e Fotônica , Espalhamento de Radiação , Propriedades de Superfície , Raios XRESUMO
The sonolytic hydrolysis of peptides with addition of phenolic reagents to aqueous solutions is described. Sonolysis of an aqueous solution of peptides to which catechol (o-dihydroxybenzene) had been added resulted in hydrolytic products reflecting the amino acid sequence without any side reactions, while sonolysis without any additives resulted in oxidation analytes and degradation products caused by side reactions. Although the use of additives such as resorcinol (m-dihydroxybenzene), hydroquinone (p-dihydroxybenzene) and phenol was also effective in producing sequence related products, several degradation products were produced by side reactions. A characteristic of the sonolysis of peptides is that the N-terminal side of proline, Xxx-Pro, is more susceptible than other amino acid residues to the process. This characteristic of sonolysis is superior to that of acid hydrolysis in which cleavage at the C-terminal side of proline, Pro-Xxx is difficult, and where dehydration products result due to side reactions.
Assuntos
Catecóis/química , Peptídeos/química , Sonicação , Catecóis/farmacologia , Hidrólise/efeitos dos fármacos , Oxirredução , Soluções , Fatores de Tempo , Água/químicaRESUMO
The pressure (or stress) wave generated by focusing a femtosecond laser pulse inside a glass has been considered one of the important factors in determining structures created in the laser focal region. In this paper, a method of the transient lens (TrL) analysis was proposed to characterize the pressure wave. Experimentally, the TrL signal exhibited damping oscillation within 2 ns. Simulations of the TrL signal showed that the shape of the oscillating signal depended on the width and amplitude of the pressure wave. Comparing the observed TrL signal with the simulated one, we estimated these properties of the pressure wave generated after femtosecond laser focusing inside a soda-lime glass.
RESUMO
To investigate the energy dissipation process after focusing a femtosecond laser pulse inside a zinc borosilicate glass, the time-dependent lens effect in the laser focal region was observed by a transient lens (TrL) method. We found that the TrL signal after 100 ns can be explained clearly by thermal diffusion. By fitting the observed signal, we obtained the phase change due to temperature increase, the initial diameter of the heated volume and the thermal diffusivity. On the basis of the results, the temperature increase and the cooling rate were estimated to be about 1800 K and 1.7X10(8) Ks(-1), respectively. We have also observed the signal change on a 100 ns scale, which can not be explained by the thermal diffusion model. This change was attributed to the relaxation of the heated material.
RESUMO
Negative feedback in the hypothalamic-pituitary-adrenal axis by exogenous glucocorticoids has been well established, but it is still in doubt whether ACTH-releasing factor (CRF) activity in the hypothalamus is inhibited by endogenous glucocorticoids under conditions of stress. In our first experiment, CRF activity in the hypothalamus of rats was significantly increased, 2 min after onset of immobilization, for 2 min; a rapid drop of CRF activity followed immediately. On the other hand, the concentration of plasma corticosterone changed more slowly; it was increased at 5 min, and showed a progressive further increase until 17 min after the administration of the immobilization stress. A high plateau level persisted for the next 8 min, after which the concentration of plasma corticosterone fell, reaching the control level at 40 min. In order to test for negative feedback inhibition by endogenous glucocorticoids in the hypothalamic-pituitary-adrenal axis, a 2nd immunobilization stress was administered to rats 5 or 23 min after the 1st stress, and hypothalamic CRF activity and plasma corticosterone were examined after the 2nd stress. When the 2nd stress was applied 5 min after the start of the 1st stress, during the phase of a gradual increase of endogenous glucocorticoids, CRF activity was not increased 2 min after the 2nd stress. In contrast, an increase of CRF activity and plasma corticosterone was observed when the 2nd stress was administered 23 min after the onset of the 1st stress, during the phase of a high plateau level of endogenous plasma corticosterone. These data suggest that CRF activity in the hypothalamus is governed by a fast feedback, rate-sensitive mechanism.
Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Glucocorticoides/metabolismo , Hipotálamo/metabolismo , Estresse Fisiológico/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Animais , Corticosterona/sangue , Retroalimentação , Masculino , Ratos , Fatores de TempoRESUMO
The response of luteinizing hormone to a single injection of synthetic LRH was established in 6 women and 7 men following an intramuscular dose of 0.2mg or 0.1mg. Significant increases of serum LH were observed in 30 min. Pretreatment with metyrapone for one day (4.5 g/sugject injection of synthetic LRH (0.1 MG/SUBJECT). Seven women, 21-48 years of age who were treated with prednisolone for a least 11/2 months were examined for responsiveness of the anterior pituitary to a single injection of synthetic LRH (0.2 MG). The secretion of LH was markedly suppressed and maximal serum levels of LH WERE OBSERVED 90 MIN FOLLOWING LRH injection.
Assuntos
Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/metabolismo , Metirapona/farmacologia , Hipófise/metabolismo , Prednisolona/farmacologia , Adulto , Feminino , Hormônio Liberador de Gonadotropina/síntese química , Humanos , Hormônio Luteinizante/sangue , Masculino , Hipófise/efeitos dos fármacos , Fatores Sexuais , Fatores de TempoRESUMO
An adult patient had a cranlopharyngloma that involved and displaced the midportion of the midbrain, producing Weber's syndrome. Oculomotor paresis in cranlopharyngloma is not always due to parasellar involvement but may be due to midbrain involvement.
Assuntos
Neoplasias Encefálicas/patologia , Craniofaringioma/patologia , Mesencéfalo , Adulto , Neoplasias Encefálicas/complicações , Neoplasias do Ventrículo Cerebral/complicações , Neoplasias do Ventrículo Cerebral/patologia , Craniofaringioma/complicações , Hemiplegia/etiologia , Humanos , Masculino , Oftalmoplegia/etiologia , SíndromeRESUMO
We describe very uncommon phenotypic and cytogenetic findings in a 40-year-old female with blast phase of Philadelphia chromosome (Ph)-positive CML. In addition to the t(9;22)(q34;q11) that was detected in all metaphases, a t(11;17)(q23;q21) was identified in 15 of 20 metaphases. Reverse transcription-polymerase chain reaction showed the major and minor bcr/abl fusion transcripts in the cells from a bone marrow (BM) sample. Fluorescence in situ hybridization (FISH) analysis also showed that fusion signals of the bcr and abl probes were found in 95% of blastic cells and in 64% of neutrophils. MLL gene rearrangement was also detected in some blastic cells but not in neutrophils by FISH analysis. Phenotypically, blastic cells expressed mixed lineage antigens such as CD34, CD33, CD13, CD19, CD7, and CD41. Immunogenotypically, some population of BM cells showed monoclonal rearrangements of immunoglobulin heavy chain and T-cell receptor gamma chain genes by Southern blot analysis. Clinical course was aggressive, and therapy was poorly tolerated. Such findings seem to support an association between Ph and an abnormality of 11q23 with poor prognosis, and suggest that the expression of both abnormal genes may be related to this mixed lineage antigen-expressing leukemia.
Assuntos
Antígenos/imunologia , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 17 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proto-Oncogenes , Fatores de Transcrição , Translocação Genética , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Southern Blotting , Transplante de Medula Óssea , Terapia Combinada , Proteínas de Ligação a DNA/genética , Feminino , Proteínas de Fusão bcr-abl/genética , Genótipo , Histona-Lisina N-Metiltransferase , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Proteína de Leucina Linfoide-Mieloide , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
We measured the plasma levels of thrombin-activatable fibrinolysis inhibitor (TAFI) activity and antigen in patients with disseminated intravascular coagulation (DIC) to examine the relationship between hypofibrinolysis and the pathogenesis of DIC. TAFI activity and antigen levels in the plasma were both significantly low in patients with DIC. TAFI activity in plasma was correlated with TAFI antigen, indicating that activity and antigen correspond well. The decrease of TAFI activity in DIC may be due to enhanced consumption. Since the plasma thrombin-antithrombin III complex (TAT) level was found to be elevated in DIC, increase of thrombomodulin-thrombin complex generation is suggested in this state. TAFI activity and antigen levels were negatively correlated with TAT and D-dimer, suggesting that the plasma levels of TAFI are reduced by thrombin generation. Since TAFI was not correlated with fibrinogen, plasma-alpha(2)plasmin inhibitor complex (PPIC) and tissue type plasminogen activator/plasminogen activator inhibitor-1 (tPA/PAI-1) complex, TAFI might be a secondary modulator of fibrinolysis. The TAFI activity in plasma was significantly low in patients with infection and in those with organ failure, suggesting that TAFI may play an important role in the mechanism of organ failure in DIC-associated sepsis. In brief, TAFI may play an important role in the pathogenesis of DIC and organ failure.
Assuntos
Carboxipeptidase B2/sangue , Coagulação Intravascular Disseminada/etiologia , Antígenos/sangue , Antitrombina III , Biomarcadores/sangue , Carboxipeptidase B2/imunologia , Estudos de Casos e Controles , Coagulação Intravascular Disseminada/sangue , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Hemostasia , Humanos , Peptídeo Hidrolases/sangue , Trombofilia/sangue , Trombofilia/etiologiaRESUMO
Four cases of intracerebral hemorrhage remote from the site of the initial neurosurgical procedure are presented. Two of the four patients had preoperative hypertension. Possible mechanisms are discussed, and labile hypertension and unstable blood pressure during the perisurgical period may be contributory. Clinical awareness of this rare but potential complication is essential to early diagnosis and treatment. Difficulty in awakening from anesthesia and the development of new neurological deficits not attributable to the operative site are the most important keys to early diagnosis. Computed tomography is the diagnostic method of choice.
Assuntos
Encefalopatias/cirurgia , Hemorragia Cerebral/diagnóstico por imagem , Complicações Intraoperatórias/diagnóstico por imagem , Adulto , Hemorragia Cerebral/etiologia , Feminino , Humanos , Hipertensão/complicações , Cuidados Intraoperatórios , Complicações Intraoperatórias/etiologia , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/etiologia , Tomografia Computadorizada por Raios XRESUMO
We report a newborn infant with a chondroma of the spine covered by a large lipoma. The child had no neurological deficit. Presenting as a tumor of the back, the chondroma was successfully excised. A review of the pertinent literature emphasizes the rarity of this lesion.
Assuntos
Condroma/cirurgia , Doenças do Recém-Nascido/cirurgia , Neoplasias da Coluna Vertebral/cirurgia , Condroma/diagnóstico por imagem , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico por imagem , Masculino , Radiografia , Neoplasias da Coluna Vertebral/diagnóstico por imagemRESUMO
The relationship between the occurrence of platelet-activating factor (PAF) and neutrophils in urine from patients with urinary tract infection was examined. PAF was detected in human pyuria, when leukocyte levels reached at least 300 cells/microL (n = 45), but not in normal urine (n = 12). The amount of PAF found in pyuria, measured by platelet aggregation assay, was 0.01 to 13.3 pmol/mL. A close correlation was seen between the amount of PAF present and the number of urinary leukocytes (p less than 0.01, r = 0.70). The leukocytes in pyuria consisted almost entirely of neutrophils (96 +/- 4%, mean +/- S.D.). Our findings suggest that the occurrence of PAF is associated with the accumulation of neutrophils in urine.
Assuntos
Fosfolipídeos/urina , Fator de Ativação de Plaquetas/urina , Piúria/urina , Animais , Cromatografia em Camada Fina , Humanos , Cinética , Éteres Fosfolipídicos/farmacologia , Fosfolipídeos/isolamento & purificação , Fosfolipídeos/farmacologia , Fator de Ativação de Plaquetas/antagonistas & inibidores , Fator de Ativação de Plaquetas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Compostos de Piridínio/farmacologia , CoelhosRESUMO
We examined activated partial thromboplastin time, kaolin clotting time, mixing with normal plasma in kaolin clotting time, dilute Russell's viper venom time, dilute Russell's viper venom time at high lipid concentrations, anti-phospholipid antibodies, and anti-cardiolipin-beta2-glycoprotein I complex antibody in 135 patients with prolongation of activated partial thromboplastin time and diagnosed 86 patients positive for lupus anticoagulant. The sensitivity of activated partial thromboplastin time and dilute Russell's viper venom time/dilute Russell's viper venom time-high lipid concentrations ratio for lupus anticoagulant were markedly high, but the specificity of activated partial thromboplastin time for lupus anticoagulant was not markedly high. The specificity, but not the sensitivity, of kaolin clotting time-mixing with normal plasma in kaolin clotting time was markedly high. In summary, dilute Russell's viper venom time to dilute Russell's viper venom time-high lipid concentrations ratio gave high sensitivity as well as specificity, being the only assay to confirm this. Of the patients positive for lupus anticoagulant, 25% were positive for anti-phospholipid antibodies and 17% were positive for anti-cardiolipin-beta2-glycoprotein I complex antibody. Of the lupus anticoagulant-positive patients with thrombosis, 45% were positive for anti-phospholipid antibodies, 35% were positive for anti-cardiolipin-beta2-glycoprotein I complex antibody, 60% were positive for both anti-phospholipid antibodies and anti-cardiolipin-beta2-glycoprotein I complex antibody, and only 17% were negative for anti-phospholipid antibodies and anti-cardiolipin-beta2-glycoprotein I complex antibody. These findings suggest that lupus anticoagulant can be diagnosed by dilute Russell's viper venom time/dilute Russell's viper venom time-high lipid concentrations ratio, and that thrombosis in lupus anticoagulant-positive may be predictable from both anti-phospholipid antibodies and anti-cardiolipin-beta2-glycoprotein I complex antibody. Plasma tissue type plasminogen activator level in lupus anticoagulant patients was significantly increased, and plasma tissue type plasminogen activator and fibrin-D-dimer levels in lupus anticoagulant-positive patients with thrombosis were significantly higher than in those without thrombosis, suggesting that the diagnosis of thrombosis by hemostatic markers might be important in lupus anticoagulant.
Assuntos
Anticorpos Antifosfolipídeos/sangue , Autoanticorpos/sangue , Testes de Coagulação Sanguínea , Inibidor de Coagulação do Lúpus/sangue , Adulto , Idoso , Criança , Transtornos de Proteínas de Coagulação/sangue , Transtornos de Proteínas de Coagulação/imunologia , Feminino , Doenças dos Genitais Femininos/sangue , Doenças dos Genitais Femininos/imunologia , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/imunologia , Tempo de Tromboplastina Parcial , Púrpura Trombocitopênica Idiopática/sangue , Púrpura Trombocitopênica Idiopática/imunologia , Tempo de Coagulação do Sangue TotalRESUMO
In this study, we examined changes in the plasma levels of total plasminogen activator inhibitor-I (PAI-I) and tissue-type plasminogen activator (tPA)/PAI-I complex in patients with disseminated intravascular coagulation (DIC) and in those with thrombotic thrombocytopenic purpura (TTP) to investigate the fibrinolytic function and its relation to organ failure. The plasma levels of total PAI-1 and tPA/PAI-I complex were significantly higher in patients with DIC, pre-DIC, and TTP than in those with non-DIC. The plasma levels of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer, thrombomodulin (TM), total PAI-I, and tPA/PAI-I complex were significantly higher in patients with organ failure than in those without organ failure. The plasma levels of total PAI-I and tPA/PAI-I complex were markedly increased in patients with acute leukemia. The plasma levels of total PAI-I, but not those of tPA/PAI-I complex, were significantly increased in patients with sepsis or with solid cancer. In all cases, total PAI-I or tPA/PAI-I complex was not significantly correlated with any hemostatic marker. Measurement of total PAI-I and tPA/PAI-I complex may be useful in the diagnosis of DIC.
Assuntos
Coagulação Intravascular Disseminada/sangue , Inibidor 1 de Ativador de Plasminogênio/análise , Púrpura Trombocitopênica Trombótica/sangue , Ativador de Plasminogênio Tecidual/análise , Antifibrinolíticos/análise , Antitrombina III/análise , Biomarcadores , Coagulação Intravascular Disseminada/complicações , Coagulação Intravascular Disseminada/diagnóstico , Endotélio Vascular/patologia , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinolisina/análise , Fibrinólise , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/complicações , Humanos , Substâncias Macromoleculares , Insuficiência de Múltiplos Órgãos/sangue , Insuficiência de Múltiplos Órgãos/etiologia , Neoplasias/sangue , Neoplasias/complicações , Peptídeo Hidrolases/análise , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ligação Proteica , Púrpura Trombocitopênica Trombótica/complicações , Sepse/sangue , Sepse/complicações , Trombomodulina/sangue , Ativador de Plasminogênio Tecidual/metabolismo , alfa 2-Antiplasmina/análiseRESUMO
A 71-year-old patient with asymptomatic calcified subdural hematoma is presented. Review of the pertinent literature indicates that the lesion should be left untreated when incidentally found or not associated with progressive neurological symptoms and signs.
Assuntos
Calcinose/cirurgia , Hematoma Subdural/cirurgia , Fatores Etários , Idoso , Humanos , MasculinoRESUMO
The case of a 12-year-old girl with fibrous dysplasia involving the cranial vault is presented. The external carotid angiogram demonstrated a dilated and beaded zygomatico-orbital branch of the superficial temporal artery, a faint tumor stain, and an early filling vein. The mass was moderately vascular at the operation and histological examination demonstrated no malignancy.
Assuntos
Displasia Fibrosa Óssea/diagnóstico por imagem , Crânio/diagnóstico por imagem , Angiografia Cerebral , Criança , Feminino , Humanos , Artérias Temporais/anormalidades , Artérias Temporais/diagnóstico por imagemRESUMO
Diencephalic syndrome of emaciation (Russell's syndrome) characteristically presents with the symptoms of marked emaciation in spite of normal linear growth and marked increased of serum growth hormone in infancy and early childhood. It is usually caused by a low-grade glioma, most often an astrocytoma, of the anterior third ventricle including the optic nerve and chiasm. Usually it is not associated with von Recklinghausen's neurofibromatosis. We describe two unusual cases of diencephalic syndrome; one case was caused by a low-grade astrocytoma involving the anterior third ventricle associated with neurofibromatosis, and the other by a malignant astrocytoma of the anterior third ventricle.
Assuntos
Emaciação/etiologia , Astrocitoma/complicações , Neoplasias Encefálicas/complicações , Ventrículos Cerebrais , Pré-Escolar , Emaciação/sangue , Emaciação/fisiopatologia , Humanos , Lactente , Masculino , Neurofibromatose 1/complicações , SíndromeRESUMO
Development of acute massive cerebral swelling within 30 minutes after closed head injury is documented by computed tomography. The swelling was rapidly resolved by steroid treatment. Detection and treatment of acute traumatic cerebral swelling are discussed briefly.
Assuntos
Edema Encefálico/diagnóstico por imagem , Lesões Encefálicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Traumatismos em Atletas/diagnóstico por imagem , Betametasona/uso terapêutico , Edema Encefálico/tratamento farmacológico , Humanos , Masculino , Fatores de TempoRESUMO
A massive hemorrhage originating in a giant celled astrocytoma of tuberous sclerosis is reported and pertinent literature is reviewed. No such association has been reported previously.
Assuntos
Astrocitoma/complicações , Neoplasias Encefálicas/complicações , Hemorragia Cerebral/etiologia , Esclerose Tuberosa/complicações , Criança , Humanos , MasculinoRESUMO
A 34-year-old female presented with a rare chronic encapsulated intracerebral hematoma associated with an angiographically occult arteriovenous malformation. A neovascularized fibrous capsule containing various stages of intracerebral hematoma formation was removed. These unusual entities mimic brain tumors or abscesses because of gradual growth and slowly progressive neurological deficits. Repeated bleeding or exudation from the capillaries of the capsule may allow expansion of the chronic encapsulated intracerebral hematoma.