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1.
Phys Rev Lett ; 132(23): 235101, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905665

RESUMEN

In this study, we discovered a turbulence transition in a large helical device. The turbulence level and turbulence-driven energy transport decrease to a specific transition density and increase above it. The ruling turbulences below and above the transition density were ion-temperature gradient (ITG) and resistive-interchange (RI) turbulences, consistent with the predictions of gyrokinetic theory and two-fluid MHD model, respectively. Isotope experiments on hydrogen (H) and deuterium (D) clarified the role of transitions. In the ITG regime, turbulence levels and energy transport were comparable in the H and D plasmas. In contrast, in the RI regime, they were clearly suppressed in the D plasma. The results provide crucial knowledge for understanding isotope effects and future optimization of stellarator and heliotron devices.

2.
Phys Rev Lett ; 128(12): 125001, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35394307

RESUMEN

Turbulence spreading into the edge stochastic magnetic layer induced by magnetic fluctuation is observed at the sharp boundary region in the large helical device. The density fluctuation excited at the sharp boundary region with a large pressure gradient does not propagate into the boundary region due to the blocking of turbulence spreading by the large second derivative of the pressure gradient. Once the magnetic fluctuation appears at the boundary, the density fluctuation begins to penetrate the edge stochastic layer and the second derivative of the pressure gradient also decreases. The increase of density fluctuation in this layer results in the broadening and reduction of the peak divertor heat load. It is demonstrated that magnetic fluctuation plays a key role in controlling the turbulence spreading at the boundary of plasma which contributes to the reduction of divertor heat load.

3.
Phys Rev Lett ; 118(12): 125001, 2017 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-28388197

RESUMEN

The resistive interchange mode destabilized by the resonant interaction with the trapped energetic ions is fully suppressed when the injected power of electron cyclotron heating exceeds a certain threshold. It is shown for the first time that the complete stabilization of the energetic-particle-driven mode without relaxing the energetic particle (EP) pressure gradient is possible by reducing the radial width of the eigenmodes δ_{w}, especially when δ_{w} narrows to a small enough value relative to the finite orbit width of EP.

4.
Rev Sci Instrum ; 93(2): 023301, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35232164

RESUMEN

In high-frequency pulsed magnets, such as kickers in particle accelerators, it is essential to reduce eddy currents that could be induced in the magnet core during excitation not to distort and attenuate the magnetic field pulse. A novel iron lamination scheme with additional interlaminar insulation is proposed for the magnet core of such pulsed magnets. A laminated steel sheet core is formed by alternately stacking thin steel and insulation sheets. For application to matched kicker magnets for accelerators, test magnets with the new and conventional iron lamination were designed, assembled, and extensively evaluated. The pulsed magnetic field waveforms of two test magnets with the new lamination successfully matched to below 0.1% over the entire pulse duration, which was significantly better than those with the conventional lamination. Among the applications of the developed high-frequency pulsed magnets, beam injection kickers for the coming next generation light sources and future colliders, where suppression of the transient stored-beam oscillation during beam injection is crucial, are considered to be promising.

5.
Sci Rep ; 12(1): 6979, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35577787

RESUMEN

The preceding propagation of turbulence pulses has been observed for the first time in heat avalanche events during the collapse of the electron internal transport barrier (e-ITB) in the Large Helical Device. The turbulence and heat pulses are generated near the foot of the e-ITB and propagate to the peripheral region within a much shorter time than the diffusion timescale. The propagation speed of the turbulence pulse is approximately 10 km/s, which is faster than that of the heat pulse propagating at a speed of 1.5 km/s. The heat pulse propagates at approximately the same speed as that in the theoretical prediction, whereas the turbulence pulse propagates one order of magnitude faster than that in the prediction, thereby providing important insights into the physics of non-local transport.

6.
Hum Reprod ; 24(12): 3042-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19684045

RESUMEN

BACKGROUND: The aim of this study was to evaluate the impact of post-operative oral contraceptives (OCs) use on the rate of recurrence after laparoscopic excision of ovarian endometrioma. METHODS: In May 2005, we introduced a 'post-operative OC recommendation' for patients treated with laparoscopic excision of endometrioma. That is, at the time of the operation, we provided each patient with information about OC, known and possible benefits and risks and let her decide whether to take OC. A retrospective cohort study included 87 patients who underwent a laparoscopy after May 2005. The endometrioma recurrence rate at 24 months was compared between those who used OC for the entire follow-up period OC (n = 34) and all of the others (n = 53). We also performed logistic regression analysis to identify variables associated with recurrence. A before-after study included another 224 patients who underwent a laparoscopy before May 2005 and compared the recurrence rate before and after introduction of the 'post-operative OC recommendation'. RESULTS: The recurrence rate in those who used OC for the entire period was significantly lower than in the 'others' group (2.9 versus 35.8%, relative risk 0.082, 95% CI 0.012-0.58, P < 0.001). Post-operative OC was determined as an independent variable associated with lower recurrence (OR 0.054, 95% CI 0.007-0.429, P < 0.001). The overall recurrence rate in patients who underwent laparoscopy after the introduction of the 'post-operative OC recommendation' was significantly lower than that in patients who received laparoscopy before the introduction (18.6 versus 33.1%, relative risk 0.56, 95% CI 0.32-0.97, P < 0.05). CONCLUSIONS: Post-operative OC use reduces the risk of ovarian endometrioma recurrence after laparoscopic excision. This information will help in appropriate planning of pre- and post-operative management.


Asunto(s)
Anticonceptivos Orales/uso terapéutico , Endometriosis/tratamiento farmacológico , Laparoscopía , Enfermedades del Ovario/tratamiento farmacológico , Ovariectomía , Adulto , Protocolos Clínicos , Terapia Combinada/estadística & datos numéricos , Endometriosis/prevención & control , Endometriosis/cirugía , Femenino , Humanos , Laparoscopía/estadística & datos numéricos , Enfermedades del Ovario/prevención & control , Enfermedades del Ovario/cirugía , Ovariectomía/estadística & datos numéricos , Cooperación del Paciente , Periodo Posoperatorio , Estudios Retrospectivos , Riesgo , Prevención Secundaria , Estadística como Asunto
7.
Clin Nephrol ; 72(6): 497-500, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19954729

RESUMEN

A case of an adolescent male with renal-coloboma syndrome (RCS) showing developmental delay is described. Birth and perinatal histories were typical. Proteinuria was initially observed at the age of 7 years during an annual mass screening program for school children. His urine was checked periodically at a local hospital. Because of an increase in proteinuria, he was referred to our hospital for further clinical evaluation. Proteinuria was moderate, ranging from 1.0 to 1.5 g/day, and was coupled with mild renal dysfunction. At that time, he was found to have myopia associated with astigmatism. He exhibited mild developmental delay, assessed by a WISC-III test. A renal biopsy sample showed marked glomerular enlargement, collapse of glomerular capillaries, mesangial matrix expansion, and tubulointerstitial change, demonstrating typical histologic features of RCS. Approximately five years after starting follow-up, the patient had severe renal dysfunction. Furthermore, optic nerve coloboma was also evident. Genetic analysis of the patient revealed a novel heterozygous mutation in exon 3 of the PAX2 gene (P130H).


Asunto(s)
Coloboma/genética , ADN/genética , Discapacidad Intelectual/genética , Riñón/anomalías , Mutación , Disco Óptico/anomalías , Factor de Transcripción PAX2/genética , Anomalías Múltiples , Coloboma/diagnóstico , Análisis Mutacional de ADN , Humanos , Discapacidad Intelectual/diagnóstico , Masculino , Síndrome , Adulto Joven
8.
Clin Exp Immunol ; 152(3): 448-55, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18422728

RESUMEN

Ageing leads to immune system dysfunction and the accumulation of autoantibodies. Because the rapid phagocytic clearance of apoptotic cells is required to prevent the development of autoimmunity, we examined the relative clearance of apoptotic material in young and aged mice using two independent assays. First, 2-year-old mice were found to be impaired in their ability to clear apoptotic keratinocytes following ultraviolet irradiation of the skin. Secondly, peritoneal macrophages exposed to apoptotic Jurkat T cells in vivo displayed diminished phagocytic activity in aged mice compared with 8-week-old mice. Consistent with these findings, aged mice exhibited signs of autoimmunity with the appearance of anti-nuclear antibodies and increased kidney glomerular size as well as complement deposits within the glomeruli. In vitro assays revealed that the pretreatment of macrophages with the serum from aged mice led to a reduction in their ability to phagocytose apoptotic bodies compared with macrophages treated with serum from young mice. These data show that the ageing process is accompanied by a diminished ability to clear apoptotic debris. This accumulation of apoptotic debris could contribute to immune system dysfunction that occurs in aged organisms.


Asunto(s)
Envejecimiento/inmunología , Apoptosis/fisiología , Animales , Líquido Ascítico/inmunología , Autoinmunidad , Senescencia Celular/inmunología , Humanos , Células Jurkat/inmunología , Queratinocitos/inmunología , Macrófagos Peritoneales/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Fagocitosis/fisiología , Piel/inmunología
9.
J Clin Invest ; 50(8): 1758-71, 1971 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4106464

RESUMEN

Thyroxine-binding alpha globulin (TBG) in human serum was isolated from Cohn fractions IV-5,6 and IV-4 by (1) chromatography on carboxymethyl (CM) cellulose, (2) gel filtration on Sephadex G-200, (3) chromatography on diethylaminoethyl-Sephadex, (4) a novel procedure of "double-gel" electrophoresis, and (5) preparative polyacrylamide gel electrophoresis. The protein was homogeneous by analytical disc gel electrophoresis, immunoelectrophoresis, and ultracentrifugal analyses (sedimentation velocity and sedimentation equilibrium), and after addition of thyroxine-(125)I showed a constant specific radioactivity on polyacrylamide electrophoresis. The sedimentation and diffusion coefficients were s(20, w), 3.0 x 10(-13) sec, and D(20, w), 8.05 x 10(-7) cm(2).sec(-1), and the molecular weight obtained by sedimentation equilibrium was 36,500. Gel filtration studies on Sephadex G-200 demonstrated that the protein had the same elution volume as that of native TBG in serum, apparently excluding the possibility of a subunit of the native protein. Chemical composition was ascertained by amino acid and carbohydrate analyses. The maximal thyroxine (T4)-binding capacity measured by reverse flow paper electrophoresis was 15,000 mug per g of protein, representing more than 2100 times that of the starting material, or about 5000 times that of whole serum. Based on the molecular weight obtained, the TBG preparation could bind 0.7 mole T4 per mole of protein, suggesting a single binding site. The association constant for T4 was estimated to be of the order of 10(10) by competitive binding studies employing TBG and T4-binding prealbumin (TBPA).


Asunto(s)
alfa-Globulinas/aislamiento & purificación , Unión Proteica , Tiroxina , alfa-Globulinas/análisis , Aminoácidos/análisis , Sitios de Unión , Electroforesis de las Proteínas Sanguíneas , Carbohidratos/análisis , Fenómenos Químicos , Química , Cromatografía , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Electroforesis Discontinua , Electroforesis en Papel , Humanos , Inmunoelectroforesis , Isótopos de Yodo , Peso Molecular , Albúmina Sérica , Ultracentrifugación
10.
Bone Joint J ; 98-B(3): 359-64, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26920961

RESUMEN

AIMS: This retrospective cohort study compared the results of vascularised and non-vascularised anterior sliding tibial grafts for the treatment of osteoarthritis (OA)of the ankle secondary to osteonecrosis of the talus. PATIENTS AND METHODS: We reviewed the clinical and radiological outcomes of 27 patients who underwent arthrodesis with either vascularised or non-vascularised (conventional) grafts, comparing the outcomes (clinical scores, proportion with successful union and time to union) between the two groups. The clinical outcome was assessed using the Mazur and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores. The mean follow-up was 35 months (24 to 68). RESULTS: The mean outcome scores increased significantly in both groups. In the vascularised graft group, the mean Mazur score improved from 36.9 to 74.6 and the mean AOFAS scale improved from 49.6 to 80.1. In the conventional arthrodesis group, the mean Mazur score improved from 35.5 to 65 and the mean AOFAS scale from 49.2 to 67.6. Complete fusion was achieved in 13 patients (76%) in the vascularised group, but only four (40%) in the conventional group. The clinical outcomes and proportion achieving union were significantly better in the vascularised group compared with the conventional arthrodesis group, although time to union was similar in the two groups. TAKE HOME MESSAGE: Vascularised sliding tibial grafts may be used to achieve arthrodesis in patients with OA of the ankle secondary to osteonecrosis of the talus.


Asunto(s)
Articulación del Tobillo/cirugía , Artrodesis/métodos , Osteoartritis/cirugía , Osteonecrosis/complicaciones , Tibia/trasplante , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/diagnóstico por imagen , Osteoartritis/etiología , Cuidados Posoperatorios/métodos , Flujo Sanguíneo Regional , Estudios Retrospectivos , Astrágalo/diagnóstico por imagen , Astrágalo/patología , Tibia/irrigación sanguínea , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
11.
Public Health Action ; 6(2): 118-21, 2016 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-27358805

RESUMEN

SETTING: Lusaka, Zambia. OBJECTIVE: To assess the actual treatment outcomes of 'transfer out' (TO) cases at a diagnostic centre in Lusaka, in the third and fourth quarters of 2012, and to see the impact of this cross-check in treatment success rates (TSR) in 2013 and early 2014. DESIGN AND METHOD: In this retrospective cohort study, treatment outcomes for new bacteriologically positive tuberculosis (TB) cases referred from the diagnostic centre were reviewed and compared with those at the receiving treatment units. RESULTS: Of 49 (58%) cases referred to three treatment units, the treatment outcomes of nine had to be updated at the diagnostic centre, which reduced the proportion of TO cases from 17.6% to 11.8% and increased the TSR to 70.6% from 64.7%. CONCLUSION: The review and cross-checking of the TB registers at the diagnostic and treatment units led to a significant reduction in non-assessed cases, suggesting that the TB registers in the diagnostic and treatment units should be cross-checked regularly. There is also need for a complementary intervention to reduce the proportion of TOs associated with high loss to follow-up and non-evaluated TO rates.


Contexte : Lusaka, Zambie.Objectif : Evaluer les vrais résultats du traitement des cas « transférés hors zone ¼ (TO) dans un centre de diagnostic, à Lusaka, pendant les troisième et quatrième trimestres de 2012, et voir l'impact du croisement des informations dans le taux de succès du traitement (TSR) en 2013 et au début de 2014.Schéma et méthode : Dans cette étude rétrospective de cohorte, les résultats du traitement de nouveaux cas de tuberculose (TB) à bactériologie positive qui avaient été référés du centre de diagnostic ont été revus et comparés à ceux de l'unité de traitement.Résultats : Sur 49 cas (58%) qui ont été référés à trois unités de traitement, les résultats du traitement de neuf cas ont dû être mis à jour au centre de diagnostic, ce qui a abouti à la réduction de la proportion de cas « TO ¼ de 17,6% à 11,8% et à l'augmentation du TSR de 64,7% à 70,6%.Conclusion : La revue et le croisement des registres TB des unités des centres de diagnostic et de traitement a abouti à une réduction significative des cas non évalués, ce qui suggère que les registres TB des unités de diagnostic et de traitement devraient être fréquemment croisés. Il y a également un besoin d'interventions complémentaires afin de réduire la proportion de TO, qui est associée à un taux élevé de perdus de vue et de cas non évalués.


Marco de referencia: La ciudad de Lusaka en Zambia.Objetivo: Evaluar los desenlaces terapéuticos reales de los pacientes con tuberculosis (TB) 'transferidos a otro centro' (TO), en una unidad de diagnóstico de Lusaka durante el tercero y cuarto trimestres del 2012 y examinar el efecto de la verificación cruzada de las tasas de éxito terapéutico (TSR) en el 2013 y comienzos del 2014.Método: En el presente estudio retrospectivo de cohortes, se analizaron los desenlaces terapéuticos de los casos nuevos de TB con confirmación bacteriológica de una unidad diagnóstica que se remitieron a otros centros y se compararon con los resultados obtenidos en las unidades de tratamiento que los recibieron.Resultados: Se remitieron 49 pacientes (58%) del centro diagnóstico a tres unidades de tratamiento. Faltaba la actualización del desenlace terapéutico de nueve de estos pacientes en el centro de diagnóstico y tras la verificación cruzada, disminuyó la proporción de casos TO de 17,6% a 11,8% y la TSR aumentó de 64,7% a 70,6%.Conclusión: La revisión y la verificación cruzada de los registros de TB de las unidades de diagnóstico y las unidades de tratamiento dio lugar a una disminución considerable de los casos clasificados como no evaluados, lo cual destaca la necesidad de cotejar con frecuencia los registros de tuberculosis de las diferentes unidades. Se precisan intervenciones complementarias encaminadas a disminuir la proporción de TO, las cuales se asocian con una alta tasa de pérdida durante el seguimiento y de casos TO no evaluados.

12.
Sci Rep ; 6: 29792, 2016 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-27465276

RESUMEN

Combined treatment strategies based on magnetic nanoparticles (MNPs) with near infrared ray (NIR) biophotonic possess tremendous potential for non-invasive therapeutic approach. Nonetheless, investigations in this direction have been limited to peripheral body region and little is known about the potential biomedical application of this approach for brain. Here we report that transient NIR exposure is dissipation-free and has no adverse effect on the viability and plasticity of major brain cells in the presence or absence superparamagnetic nanoparticles. The 808 nm NIR laser module with thermocouple was employed for functional studies upon NIR exposure to brain cells. Magnetic nanoparticles were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic laser scattering (DLS), and vibrating sample magnetometer (VSM). Brain cells viability and plasticity were analyzed using electric cell-substrate impedance sensing system, cytotoxicity evaluation, and confocal microscopy. When efficacious non-invasive photobiomodulation and neuro-therapeutical targeting and monitoring to brain remain a formidable task, the discovery of this dissipation-free, transient NIR photonic approach for brain cells possesses remarkable potential to add new dimension.


Asunto(s)
Nanopartículas de Magnetita/toxicidad , Astrocitos/efectos de los fármacos , Encefalopatías/terapia , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Espectroscopía de Resonancia por Spin del Electrón , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestructura , Tamaño de la Partícula , Espectrofotometría Infrarroja
13.
J Clin Pathol ; 58(7): 729-33, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15976341

RESUMEN

BACKGROUND: Excessive use of broad spectrum antibiotics is related to the spread of drug resistant bacterial strains in the community. AIM/METHODS: The effects of immediate testing for C reactive protein (CRP) and white blood cell count (WBC) on physicians' choices of antibiotic was investigated in patients with acute infection. Acutely febrile new outpatients were randomised into two groups: group 1 (147 patients) underwent CRP and WBC testing before initial consultation (advance testing). Prescriptions were compared with those in group 2 (no advance testing; 154 patients). RESULTS: In non-pneumonic acute respiratory tract infections, 61 (58%) and 122 (91%) of group 1 and 2 patients were prescribed antibiotics, respectively. Cefcapene pivoxil (third generation cephalosporin) and amoxicillin were the most frequently chosen drugs for group 1 and 2, respectively. Total prescriptions of newer, extended spectrum antibiotics (cefcapene pivoxil and clarithromycin (advanced macrolide)) were reduced by 25% in group 1, although they increased in rate (41 (67%) v 55 (45%) prescriptions) because of the decreased prescription of amoxicillin. In group 1, cefcapene pivoxil was preferentially selected when WBC values were greater than 9 x 10(9)/litre. Prescription shifted to macrolides (mainly clarithromycin) in patients without leucocytosis. Patient treatment outcome did not significantly differ between the two groups. CONCLUSIONS: The availability of CRP and WBC data during initial consultation greatly reduced prescription of amoxicillin, but had a lesser effect on newer, potent, broad spectrum antibiotics.


Asunto(s)
Antibacterianos/administración & dosificación , Infecciones Bacterianas/diagnóstico , Proteína C-Reactiva/análisis , Fiebre/microbiología , Pautas de la Práctica en Medicina , Enfermedad Aguda , Adulto , Amoxicilina/administración & dosificación , Infecciones Bacterianas/sangre , Infecciones Bacterianas/tratamiento farmacológico , Biomarcadores/sangre , Cefalosporinas/administración & dosificación , Claritromicina/administración & dosificación , Fiebre/sangre , Humanos , Japón , Recuento de Leucocitos , Persona de Mediana Edad , Servicio Ambulatorio en Hospital , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Resultado del Tratamiento
14.
Diabetes Care ; 20(8): 1324-8, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9250463

RESUMEN

OBJECTIVE: To evaluate the peripheral sympathetic function in feet of NIDDM patients by means of laser Doppler flowmetry. RESEARCH DESIGN AND METHODS: After deep inspiration, we measured the vasoconstrictor response in the feet of 51 patients with NIDDM, as compared with those of 20 healthy control subjects, using laser Doppler flowmetry. Subjects whose skin temperature was < 32 degrees C were excluded from our study because a skin temperature of approximately 34 degrees C is the optimal temperature for the evaluation of skin vasomotor reflexes in response to a deep inspiration by laser Doppler flowmetry. RESULTS: The vasoconstrictor response to deep inspiration in the big toe was significantly decreased in NIDDM patients compared with healthy subjects (26.8 +/- 2.0 vs. 48.3 +/- 18.5%, P < 0.0001). In NIDDM patients, the vasoconstrictor response was positively correlated with the duration of diabetes, the median motor and sensory nerve conduction velocities, the coefficient of variation of the R-R interval at rest, and the postural fall in systolic blood pressure. The vasoconstriction was inversely correlated with the vibratory perception threshold. CONCLUSIONS: Vasomotor reflexes in the lower limbs were markedly impaired in NIDDM patients. The measurement of vasoconstrictor responses to deep inspiration by using laser Doppler flowmetry is a novel and useful method for detecting peripheral sympathetic failure in diabetic patients.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Neuropatías Diabéticas/diagnóstico , Flujometría por Láser-Doppler/métodos , Reflejo/fisiología , Respiración/fisiología , Piel/irrigación sanguínea , Velocidad del Flujo Sanguíneo , Neuropatías Diabéticas/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Piel/inervación , Temperatura Cutánea , Sistema Nervioso Simpático/fisiopatología , Dedos del Pie/irrigación sanguínea , Vasoconstricción
15.
Diabetes Care ; 21(7): 1173-7, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9653615

RESUMEN

OBJECTIVE: To evaluate the relationship between diabetic autonomic neuropathy and diabetic neuropathic foot ulceration, we used power spectral analysis (PSA) of heart rate variation, which provides the accurate simultaneous quantification of parasympathetic and sympathetic activities, to assess autonomic function in diabetic patients. RESEARCH DESIGN AND METHODS: We studied 55 NIDDM patients including 10 diabetic patients without neuropathy, 23 diabetic patients with neuropathy and no history of foot ulceration, and 22 diabetic patients with neuropathic foot ulceration. We performed PSA of 100 R-R intervals at rest and analyzed the results by fast Fourier transformation. RESULTS: The low frequency (LF) power, which reflects sympathetic activity, and the high frequency (HF) power, which reflects parasympathetic (vagal) activity, were inversely correlated with the duration of diabetes and the fasting plasma glucose (FPG) levels. By multiple regression analysis, the FPG remained with significant influence on both LF and HF powers. The LF and HF powers were positively correlated with motor nerve conduction velocity (MCV) and sensory nerve conduction velocity (SCV) in the upper and lower limbs and the coefficient of variation of R-R intervals. The LF and HF powers were significantly reduced in patients with neuropathy and patients with foot ulceration compared with patients without neuropathy. Although the median MCV and SCV were similar between diabetic patients with neuropathy and patients with foot ulceration, both the LF and HF powers were significantly decreased in patients with foot ulceration compared with patients with neuropathy. There was no difference in the value of the LF:HF ratio, an index of sympathovagal balance, among three subgroups. We observed a positive correlation between LF and HF power in all subjects; however, the LF and HF powers were not correlated in the subgroups of patients with foot ulceration. CONCLUSIONS: These results showed that diabetic patients with neuropathic foot ulceration have a greater impairment in spectral indexes of autonomic activity obtained by PSA than patients with neuropathy and no history of foot ulceration, whereas no difference was present in nerve conduction velocities.


Asunto(s)
Pie Diabético/fisiopatología , Neuropatías Diabéticas/fisiopatología , Electrocardiografía/métodos , Frecuencia Cardíaca/fisiología , Factores de Edad , Sistema Nervioso Autónomo/fisiopatología , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Pie Diabético/complicaciones , Neuropatías Diabéticas/complicaciones , Ayuno , Femenino , Análisis de Fourier , Hemoglobina Glucada/metabolismo , Corazón/inervación , Corazón/fisiología , Humanos , Masculino , Persona de Mediana Edad , Neuronas Motoras/fisiología , Conducción Nerviosa/fisiología , Análisis de Regresión , Factores de Tiempo
16.
Exp Hematol ; 17(7): 795-9, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2502422

RESUMEN

The effects of recombinant preparations of human interferon-gamma (rIFN-gamma) and tumor necrosis factor (rTNF), alone or in combination, on class I or class II major histocompatibility complex (MHC) antigen induction were studied using K562, a multipotent hematopoietic precursor cell line. Class I antigens were weakly induced by rIFN-gamma; however, rTNF at any concentration examined (1-1000 U/ml) showed no effect on the induction of class I or class II antigens in the cells. rIFN-gamma (600 U/ml) induced approximately 20% of the cells to express class I antigens after 72-h exposure, whereas 81% of the cells demonstrated class I antigens on their cell surfaces when the cells were simultaneously exposed to 600 U/ml of rIFN-gamma and 1000 U/ml of rTNF. The class II MHC antigens were not induced by the treatments with rIFN-gamma or rTNF, alone or in combination. A synergistic increase of mRNA for class I MHC molecules was demonstrated by treatments of the cells with rIFN-gamma and rTNF in combination. rTNF, but not rIFN-gamma, weakly induced granulocyte-monocyte antigens on the cell surface; however, no synergism was observed on the induction of these antigens by the combined treatments with rIFN-gamma and rTNF. These results indicate that class I MHC antigen expression on K562 cells can be induced by IFN-gamma in cooperation with TNF in a manner different from myeloid antigen expression.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/inmunología , Interferón gamma/farmacología , Leucemia Mieloide/patología , Factor de Necrosis Tumoral alfa/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Regulación de la Expresión Génica/efectos de los fármacos , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Técnicas In Vitro , ARN Mensajero/genética , Proteínas Recombinantes , Células Tumorales Cultivadas
17.
Bone Joint J ; 97-B(6): 802-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26033060

RESUMEN

A new method of vascularised tibial grafting has been developed for the treatment of avascular necrosis (AVN) of the talus and secondary osteoarthritis (OA) of the ankle. We used 40 cadavers to identify the vascular anatomy of the distal tibia in order to establish how to elevate a vascularised tibial graft safely. Between 2008 and 2012, eight patients (three male, five female, mean age 50 years; 26 to 68) with isolated AVN of the talus and 12 patients (four male, eight female, mean age 58 years; 23 to 76) with secondary OA underwent vascularised bone grafting from the distal tibia either to revascularise the talus or for arthrodesis. The radiological and clinical outcomes were evaluated at a mean follow-up of 31 months (24 to 62). The peri-malleolar arterial arch was confirmed in the cadaveric study. A vascularised bone graft could be elevated safely using the peri-malleolar pedicle. The clinical outcomes for the group with AVN of the talus assessed with the mean Mazur ankle grading scores, improved significantly from 39 points (21 to 48) pre-operatively to 81 points (73 to 90) at the final follow-up (p = 0.01). In all eight revascularisations, bone healing was obtained without progression to talar collapse, and union was established in 11 of 12 vascularised arthrodeses at a mean follow-up of 34 months (24 to 58). MRI showed revascularisation of the talus in all patients. We conclude that a vascularised tibial graft can be used both for revascularisation of the talus and for the arthrodesis of the ankle in patients with OA secondary to AVN of the talus.


Asunto(s)
Artrodesis/métodos , Trasplante Óseo/métodos , Osteoartritis/cirugía , Osteonecrosis/cirugía , Astrágalo , Tibia/trasplante , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteonecrosis/diagnóstico por imagen , Osteonecrosis/patología , Radiografía , Procedimientos de Cirugía Plástica , Esclerosis , Astrágalo/diagnóstico por imagen , Astrágalo/patología , Tibia/irrigación sanguínea
18.
J Clin Endocrinol Metab ; 80(7): 2173-7, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7608274

RESUMEN

In order to investigate the extrapituitary action of TRH on the thyroid, serum T3, T4, and TSH levels after im administration of TRH were analyzed in 63 patients with untreated hyperthyroid Graves' disease, in 60 euthyroid patients with treated Graves' disease, in 8 patients with subacute thyroiditis, and in 140 healthy subjects. TRH administration in the healthy subjects resulted in a significant increase in serum T3 and T4 levels after 2 h. However, in the patients with untreated hyperthyroid Graves' disease, a significant decrease in serum T3 and T4 levels with undetectable TSH was found 2 h after TRH administration. In the patients with subacute thyroiditis, serum T3 levels also significantly decreased after TRH administration. When a decrease in serum T3 and T4 levels after TRH administration in the patients with hyperthyroid Graves' disease was analyzed in terms of thyroid microsomal antibody and thyroglobulin antibody, a decrease in serum T3 and T4 levels was largest in patients with thyroid microsomal antibody and thyroglobulin antibody. In contrast, an increase in serum T3 and T4 levels in response to TRH in the euthyroid patients with Graves' disease was largest in patients without thyroid autoantibodies. It is concluded that TRH acts directly on the thyroid to suppress the thyroid hormone secreting activity in the absence of circulating TSH and that thyroid autoantibodies affect thyroidal response after TRH administration.


Asunto(s)
Enfermedad de Graves/sangre , Metimazol/uso terapéutico , Tiroiditis Subaguda/sangre , Hormona Liberadora de Tirotropina/farmacología , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre , Adolescente , Adulto , Anciano , Autoanticuerpos/sangre , Niño , Femenino , Enfermedad de Graves/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Glándula Tiroides/inmunología
19.
J Clin Endocrinol Metab ; 84(10): 3602-5, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10523002

RESUMEN

To investigate the possible participation of immunoglobulin E (IgE) in the autoimmune process of Graves' disease, incidence of elevation of serum IgE level, TSH receptor antibody (TRAb), and thyroid status were studied in 66 patients with hyperthyroid Graves' disease, 54 patients with Hashimoto's thyroiditis, 19 patients with bronchial asthma, and 15 patients with pollen allergy. In hyperthyroid Graves' patients, elevation of serum IgE levels (> or = 170 U/mL) was found in 19 of 66 patients (29%), 11 of whom had hereditary and/or allergic conditions. Elevations of serum IgE levels were found in 63% of patients with bronchial asthma and in 40% of patients with pollen allergy. Mean values of serum IgE were the same in patients with hyperthyroid Graves' disease and with bronchial asthma. During methimazole treatment TRAb decreased without fluctuation of IgE levels in both groups. The decrease in TRAb was significantly greater in patients with normal IgE than in patients with IgE elevation. After prednisone administration, reduction in TRAb was greater in patients with normal IgE than that in patients with IgE elevation. High incidence of IgE elevation in hyperthyroid Graves' disease and slower reduction in TRAb in association with IgE elevation suggest a difference in the autoimmune processes in Graves' disease with and without elevation of IgE.


Asunto(s)
Enfermedad de Graves/fisiopatología , Inmunoglobulina E/fisiología , Adolescente , Adulto , Anciano , Antitiroideos/uso terapéutico , Asma/sangre , Asma/tratamiento farmacológico , Femenino , Glucocorticoides/uso terapéutico , Enfermedad de Graves/sangre , Enfermedad de Graves/tratamiento farmacológico , Humanos , Hipersensibilidad/sangre , Hipersensibilidad/tratamiento farmacológico , Inmunoglobulina E/sangre , Masculino , Metimazol/uso terapéutico , Persona de Mediana Edad , Polen/inmunología , Prednisona/uso terapéutico , Enfermedades de la Tiroides/sangre , Enfermedades de la Tiroides/tratamiento farmacológico , Enfermedades de la Tiroides/fisiopatología , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/fisiopatología
20.
FEBS Lett ; 410(2-3): 493-8, 1997 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-9237690

RESUMEN

Protein kinase B (PKB, also named as Akt or RAC-protein kinase), that is activated by cellular stress such as heat shock and hyperosmotic treatment, was revealed to be activated by oxidative stress and by chemical stressors of CdCl2 and NaAsO2 by measuring the activity of the enzyme immunoprecipitated from the transfected COS-7 cells. Upon stress treatment, a 30-kDa phosphoprotein was co-immunoprecipitated with PKB from the cells metabolic labeled with [32P]orthophosphate. The phosphoprotein was identified as Hsp27, a small heat shock protein, by immunoblot analysis and co-immunoprecipitation. The association of Hsp27 was specific to PKB as the heat shock protein was not co-immunoprecipitated with other protein kinases such as protein kinase C and PKN. When the cells were treated with H2O2, PKB was activated gradually and the association of Hsp27 with PKB increased concurrently with the enhancement of PKB activity. In heat-shocked cells, activation of PKB and the association of Hsp27 were detected immediately after the treatment, and the association of the heat shock protein decreased while PKB kept stimulated activity when the cells were further incubated at 37 degrees C. These results suggest that Hsp27 is involved in the activation process of PKB in the signal transduction pathway of various forms of stress.


Asunto(s)
Estrés Oxidativo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Animales , Arseniatos/farmacología , Células COS , Cloruro de Cadmio/farmacología , Activación Enzimática , Humanos , Peróxido de Hidrógeno/farmacología , Péptidos y Proteínas de Señalización Intracelular , Fosforilación , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-akt , Estimulación Química
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