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1.
Mali Med ; 36(2): 19-22, 2021.
Artículo en Francés | MEDLINE | ID: mdl-37973584

RESUMEN

INTRODUCTION: High blood pressure is a major cardiovascular risk factor. Patients with cardiovascular risk factors are at risk of developing COVID-19. The objective of this study was to determine epidemiology of Covid-19 infected in patients with high blood pressure. PATIENTS AND METHOD: Descriptive cross-sectional study from April 2020 to June 2020 about patients hospitalized for Covid 19 by PCR diagnosis at the Hopital du Mali Bamako and having high blood pressure. Admission registry and patient charts were used to collect data. RESULTS: We collected 78 out of 484 in patients which mean hospital frequency of 16.11%. The mean age was 55.21 +/- 14.61 years. Sex ratio M / F was 1.36. Patients were followed for high blood pressure in 59% of cases. Medical history was ischemic heart disease in 2.6% and dilated cardiomyopathy in 2.6%. Main functional signs were cough in 41.02% and lost of taste in 11.53%. High blood pressure on admission was grade 2 in 37.2% and grade 3 in 3.8%. Treatments received were calcium channel blockers 41.02%, inhibitors of the reninangiotensinaldosterone system 16.66% and combinations 15.38%. Hospital mortality was 10.3%. There was no statistically significant difference in mortality between known hypertensive patients and de novo hypertensive patients. There was also no statistically significant difference in mortality by grade of hypertension. CONCLUSION: High blood pressure can be associated to Covid 19. Treatment is based on calcium channel blockers and reninangiotensinaldosterone system inhibitors. It has an impact on the prognosis of the disease with significant mortality.


INTRODUCTION: L'hypertension artérielle (HTA) est un facteur de risque cardiovasculaire majeur. Dans la littérature elle est fréquemment retrouvée chez les patients atteints de la COVID-19.L'objectif de cette étude est de décrire l'épidémiologie de cette association chez les patients hospitalisés pour Covid-19. PATIENTS ET MÉTHODE: L'Etude est transversale et descriptive ; elle a été réalisée sur la période du 1erAvril 2020 au 30 Juin 2020. Elle a concerné les patients hospitalisés pour Covid 19 avec un test PCR positif à l'hôpital du Mali de Bamako et ayant une HTA. Les registres d'admission et les dossiers des patients ont servi pour la collecte des données. RÉSULTATS: Nous avons colligé 78 sur 484 patients hospitalisés soit une fréquence de 16,11%. L'âge moyen était de 55,21 +/- 14,61 ans. Le sex ratio H/F était de 1,36.Les patients étaient suivis pour HTA dans 59% des cas. Les antécédents médicaux étaient la cardiopathie ischémique chez 2,6% et la cardiomyopathie dilatée chez 2,6%. Les principaux signes fonctionnels étaient la toux chez 41,02% et l'agueusie chez 11,53%. L'HTA à l'admission était de grade 2 dans 37,2% des cas et de grade 3 dans 3,8% des cas. Les traitements reçus étaient les inhibiteurs calciques 41,02%, les inhibiteurs du système rénine angiotensine aldostérone 16,66% et les associations 15,38%. La mortalité hospitalière était de 10,3%. Il n'y avait pas de différence statistiquement significative concernant la mortalité entre les patients connus hypertendus et les patients hypertendus de novo. Il n'y avait pas non plus de différence statistiquement significative concernant la mortalité selon le grade de l'HTA. CONCLUSION: l'HTA peut être associée au Covid 19. Le traitement est basé sur les inhibiteurs calciques et sur les inhibiteurs du système rénine angiotensine aldostérone. Elle a un impact sur le pronostic de la maladie avec une mortalité importante.

2.
Phys Rev Lett ; 125(25): 252501, 2020 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-33416401

RESUMEN

The formation of a dineutron in the ^{11}Li nucleus is found to be localized to the surface region. The experiment measured the intrinsic momentum of the struck neutron in ^{11}Li via the (p,pn) knockout reaction at 246 MeV/nucleon. The correlation angle between the two neutrons is, for the first time, measured as a function of the intrinsic neutron momentum. A comparison with reaction calculations reveals the localization of the dineutron at r∼3.6 fm. The results also support the density dependence of dineutron formation as deduced from Hartree-Fock-Bogoliubov calculations for nuclear matter.

3.
Pharmazie ; 74(5): 286-289, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-31109398

RESUMEN

Various types of fluorescent lights are found in the dispensing rooms of medical facilities, such as hospitals and pharmacies, in Japan. However, to reduce electric power consumption, it was necessary to evaluate the substitution of fluorescent lighting with light emitting diode (LED) lighting, which has become widespread in recent years. We subjectively evaluated several types of medicines stored under various light sources and found that different color changes were induced in tablets. In this study, we focused on Perlodel ® tablets, containing 2.5 mg bromocriptine mesylate, as an example for the objective evaluation of the differences in the color change of tablets when stored under LED lighting and fluorescent lighting. High-performance liquid chromatography (HPLC) analysis of part of the tablet surface area revealed a change from white to light brown or dark brown after 28 days of irradiation, with a residual concentration of bromocriptine mesylate of 85.5 % under fluorescent lighting, 85.6 % under daylight-color LED lighting, 90.3 % under bulb-color LED lighting, and 99.2 % in the dark. In addition, the ultraviolet (UV)-visible spectral study of the absorbance of a photo-product at 400-550 nm indicated that the color change of the Perlodel® 2.5 mg tablet was caused by photochemical degradation of bromocriptine mesylate. Thus, this analysis of the photochemical changes in drugs stored under different light sources demonstrated the potency of LED lights. Through the objective evaluation of the color change, the cause of the color change was determined; this will allow us to develop a strategy that minimizes possible disadvantages to patients, such as a decrease in treatment efficacy owing to decomposition of the main component or adverse caused by decomposed matter.


Asunto(s)
Bromocriptina/química , Bromocriptina/efectos de la radiación , Cromatografía Líquida de Alta Presión , Color , Estabilidad de Medicamentos , Iluminación , Fotólisis , Comprimidos/química , Comprimidos/efectos de la radiación , Temperatura
4.
Phys Rev Lett ; 121(13): 132501, 2018 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-30312098

RESUMEN

The key parameter to discuss the possibility of the pion condensation in nuclear matter, i.e., the so-called Landau-Migdal parameter g^{'}, was extracted by measuring the double-differential cross sections for the (p,n) reaction at 216 MeV/u on a neutron-rich doubly magic unstable nucleus, ^{132}Sn with the quality comparable to data taken with stable nuclei. The extracted strengths for Gamow-Teller (GT) transitions from ^{132}Sn leading to ^{132}Sb exhibit the GT giant resonance (GTR) at the excitation energy of 16.3±0.4(stat)±0.4(syst) MeV with the width of Γ=4.7±0.8 MeV. The integrated GT strength up to E_{x}=25 MeV is S_{GT}^{-}=53±5(stat)_{-10}^{+11}(syst), corresponding to 56% of Ikeda's sum rule of 3(N-Z)=96. The present result accurately constrains the Landau-Migdal parameter as g^{'}=0.68±0.07, thanks to the high sensitivity of the GTR energy to g^{'}. In combination with previous studies on the GTR for ^{90}Zr and ^{208}Pb, the result of this work shows the constancy of this parameter in the nuclear chart region with (N-Z)/A=0.11 to 0.24 and A=90 to 208.

6.
J Med Genet ; 45(12): 802-7, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18611981

RESUMEN

OBJECTIVE: Severe congenital neutropenia (SCN), also known as Kostmann syndrome (SCN3, OMIM 610738), includes a variety of haematological disorders caused by different genetic abnormalities. Mutations in ELA2 are most often the cause in autosomal dominant or sporadic forms. Recently, mutations in HAX1 have been identified as the cause of some autosomal recessive forms of SCN, including those present in the original pedigree first reported by Kostmann. We sought to determine the relationship between HAX1 gene mutations and the clinical characteristics of Japanese cases of SCN. METHODS: The genes implicated in SCN (ELA2, HAX1, Gfi-1, WAS, and P14) were analysed in 18 Japanese patients with SCN. The clinical features of these patients were obtained from medical records. Immunoblotting of HAX1 was performed on cell extracts from peripheral blood leucocytes from patients and/or their parents. RESULTS: We found five patients with HAX1 deficiency and 11 patients with mutations in the ELA2 gene. In HAX1 deficiency, a homozygous single base pair substitution (256C>T), which causes the nonsense change R86X, was identified in three affected individuals. Two sibling patients showed a compound heterozygous mutation consisting of a single base pair substitution (256C>T) and a 59 bp deletion at nucleotides 376-434. There was no detectable phenotype in any heterozygous carrier. All patients with HAX1 deficiency had experienced developmental delay. Three patients carrying R86X also suffered from epileptic seizures. In contrast, no SCN patient with heterozygous mutations in the ELA2 gene suffered from any neurodevelopmental abnormality. CONCLUSIONS: These findings suggest that the R86X mutation in the HAX1 gene is an abnormality in Japanese SCN patients with HAX1 deficiency and may lead to neurodevelopmental abnormalities and severe myelopoietic defects.


Asunto(s)
Discapacidades del Desarrollo/genética , Mutación , Neutropenia/congénito , Neutropenia/genética , Proteínas/genética , Proteínas Adaptadoras Transductoras de Señales , Secuencia de Bases , Femenino , Homocigoto , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , Linaje
7.
Bone Marrow Transplant ; 40(3): 251-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17549054

RESUMEN

We initially conducted a multicenter, randomized trial (n=43), and subsequently a questionnaire study (n=209) of participating hospitals, to evaluate whether infused fresh frozen plasma (FFP) could prevent the occurrence of hepatic veno-occlusive disease (VOD) after stem cell transplantation (SCT). Forty-three patients were divided into two groups: 23 receiving FFP infusions and 20 not receiving it. VOD developed in three patients not receiving FFP. Plasma von Willebrand factor (VWF) antigen levels were lower at days 0, 7 and 28 after SCT in patients receiving FFP than in those not receiving it, whereas plasma ADAMTS13 activity (ADAMTS13:AC) did not differ between them. Plasma VWF multimer (VWFM) was demonstrated to be defective in the high approximately intermediate VWFM during the early post-SCT phase, but there was a significant increase in high VWFM just before VOD onset. This suggests that a relative enzyme-to-substrate (ADAMTS13/high-VWFM) imbalance is involved in the pathogenesis of VOD. To strengthen this hypothesis, the incidence of VOD was apparently lower in patients receiving FFP infusions than in those not receiving it (0/23 vs 3/20) in the randomized trial. Further, the results combined with the subsequent questionnaire study (0/36 vs 11/173) clearly showed the incidence to be statistically significant (0/59 vs 14/193, P=0.033).


Asunto(s)
Proteínas ADAM/sangre , Enfermedad Veno-Oclusiva Hepática/prevención & control , Plasma , Trasplante de Células Madre , Factor de von Willebrand/análisis , Proteína ADAMTS13 , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Neoplasias Hematológicas/sangre , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/patología , Neoplasias Hematológicas/terapia , Enfermedad Veno-Oclusiva Hepática/sangre , Enfermedad Veno-Oclusiva Hepática/etiología , Enfermedad Veno-Oclusiva Hepática/patología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Plasma/enzimología
8.
J Thromb Haemost ; 3(2): 361-8, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15670045

RESUMEN

WAVE isoforms, which consist of WAVE-1, WAVE-2 and WAVE-3, are members of the Wiskott-Aldrich syndrome protein (WASP) family. They are implicated in the regulation of actin-cytoskeletal reorganization downsteam of the small GTPase, Rac. Since platelet attachment to extracellular matrices leads to filopodial and lamellipodial extension, we examined the expression and subcellular localization of WAVEs in platelets. Employing primary megakaryocytic cells derived from cord blood as well as megakaryocytic cell lines, we also examined their expression during megakaryocytic differentiation. Immunoblotting and immunohistochemical analysis revealed that platelets expressed WAVE-1 and WAVE-2, whereas WAVE-3 expression was hardly to be detected. WAVE-1 expression was associated with megakaryocytic differentiation, whereas WAVE-2 and WAVE-3 expression was not changed by the differentiation. In adhered platelets both WAVE-1 and WAVE-2 were localized at the edge of the lamellipodia and at the tips of filopodia. In WASP-deficient platelets we found normal lamellipodial formation and localization of WAVE-1 and WAVE-2 at the edges of lamellipodia. Furthermore, we demonstrated that WAVE-1 and WAVE-2 moved from a detergent-soluble cytosolic fraction to insoluble cytoskeleton fraction after platelet aggregation. These results suggest that WAVE-1 and WAVE-2 regulate actin reorganization during platelet spreading and aggregate formation.


Asunto(s)
Plaquetas/química , Megacariocitos/química , Proteínas de Microfilamentos/metabolismo , Plaquetas/citología , Diferenciación Celular , Linaje de la Célula , Citoesqueleto/metabolismo , Citosol/metabolismo , Humanos , Megacariocitos/citología , Proteínas de Microfilamentos/análisis , Adhesividad Plaquetaria , Transporte de Proteínas , Proteínas , Seudópodos/química , Familia de Proteínas del Síndrome de Wiskott-Aldrich
10.
Tissue Antigens ; 64(5): 611-5, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15496206

RESUMEN

Mediation of Epstein-Barr virus (EBV)-specific cytotoxicity in T lymphocyte via the perforin/granzyme pathway has been demonstrated; therefore, a study involving cytolytic molecules was essential for the clarification of hemophagocytic lymphohistiocytosis (HLH) pathogenesis. This investigation, which analysed the frequency of three allelic mutations of granzyme-B (55Q/R, 95P/A and 247Y/H) in patients with EBV-HLH and infectious mononucleosis, identified the high prevalence of the QPY haplotype in EBV-HLH patients in comparison with healthy controls. A > G polymorphism was also detected in intron 5; furthermore, nearly complete linkage disequilibrium was observed among these polymorphisms. The recessive role of the QPY haplotype of granzyme-B might be responsible for the pathogenesis of EBV-HLH. Cytotoxicity and DNA fragmentation of cytotoxic T lymphocytes did not differ among patients characterized by the QPY/QPY, RAH/RAH and QPY/RAH genotypes. This finding suggested that DNA fragmentation in target cells is mediated not only by granzyme-B but also by other molecules, including other granzymes or Fas.


Asunto(s)
Predisposición Genética a la Enfermedad , Histiocitosis de Células no Langerhans/genética , Desequilibrio de Ligamiento , Serina Endopeptidasas/genética , Granzimas , Herpesvirus Humano 4/metabolismo , Histiocitosis de Células no Langerhans/inmunología , Histiocitosis de Células no Langerhans/virología , Mutación Puntual , Linfocitos T/inmunología
11.
J Med Genet ; 41(10): 763-7, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15466010

RESUMEN

BACKGROUND: Familial haemophagocytic lymphohistiocytosis (FHL) has an autosomal recessive mode of inheritance and consists of at least three subtypes. FHL2 subtype with perforin (PRF1) mutation accounts for 30% of all FHL cases, while FHL with MUNC13-4 mutation was recently identified and designated as FHL3 subtype. OBJECTIVE: To examine MUNC13-4 mutations and the cytotoxic function of MUNC13-4 deficient T lymphocytes in Japanese FHL patients METHODS: Mutations of MUNC13-4 and the cytotoxicity of MUNC13-4-deficient cytotoxic T lymphocytes (CTL) were analysed in 16 Japanese families with non-FHL2 subtype. RESULTS: Five new mutations of the MUNC13-4 gene were identified in six families. The mutations were in the introns 4, 9, and 18, and exons 8 and 19. Two families had homozygous mutations, while the remaining four had compound heterozygous mutations. Cytotoxicity of MUNC13-4 deficient CTL was low compared with control CTL, but was still present. Clinically, the onset of disease tended to occur late; moreover, natural killer cell activity was not deficient in some FHL3 patients. CONCLUSIONS: MUNC13-4 mutations play a role in the development of FHL3 through a defective cytotoxic pathway.


Asunto(s)
Histiocitosis de Células no Langerhans/genética , Mutación/genética , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/genética , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismo , Edad de Inicio , Análisis Mutacional de ADN , Exones/genética , Femenino , Histiocitosis de Células no Langerhans/inmunología , Histiocitosis de Células no Langerhans/fisiopatología , Humanos , Lactante , Intrones/genética , Japón , Masculino , Datos de Secuencia Molecular , Linaje
12.
Nature ; 430(7000): 648-50, 2004 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-15295592

RESUMEN

Over the six years since the discovery of the gamma-ray burst GRB 980425, which was associated with the nearby (distance approximately 40 Mpc) supernova 1998bw, astronomers have debated fiercely the nature of this event. Relative to bursts located at cosmological distance (redshift z approximately 1), GRB 980425 was under-luminous in gamma-rays by three orders of magnitude. Radio calorimetry showed that the explosion was sub-energetic by a factor of 10. Here we report observations of the radio and X-ray afterglow of the recent GRB 031203 (refs 5-7), which has a redshift of z = 0.105. We demonstrate that it too is sub-energetic which, when taken together with the low gamma-ray luminosity, suggests that GRB 031203 is the first cosmic analogue to GRB 980425. We find no evidence that this event was a highly collimated explosion viewed off-axis. Like GRB 980425, GRB 031203 appears to be an intrinsically sub-energetic gamma-ray burst. Such sub-energetic events have faint afterglows. We expect intensive follow-up of faint bursts with smooth gamma-ray light curves (common to both GRB 031203 and 980425) to reveal a large population of such events.

13.
Phytomedicine ; 11(4): 331-7, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15185847

RESUMEN

A new isoflavonoid, together with four known isoflavonoids, was isolated from the roots of Erythrina poeppigiana. The chemical structure was determined by extensive spectroscopic studies, and then its antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) was investigated. The new isoflavonoid was identified as 3,9-dihyroxy-10-gamma,gamma-dimethylallyl-6a,11a-dehydropterocarpan (compound 1). Compound 1 inhibited bacterial growth most potently of the five isolates, and had a minimum inhibitory concentration (MIC) of 125 microg/ml against thirteen MRSA strains. Inhibitory activity was based on bactericidal action and viable cell number reduced by approximately 1/10,000 after 4 h incubation with compound 1. Despite intense bactericidal action against MRSA, compound 1 never resulted in leakage of 260 nm-absorbing substances from bacterial cells. Compound 1 (12.5 microg/ml) completely inhibited incorporation of radio-labeled thymidine, uridine and leucine into MRSA cells. Although glucose incorporation was also markedly inhibited by the compound, the amount of glucose incorporated by bacterial cells increased gradually with incubation time. These findings suggest that compound 1 exhibits anti-MRSA activity by interfering with incorporation of metabolites and nutrients into bacterial cells or by affecting the nucleic acids of MRSA cells. Furthermore, this new compound could be a potent phytotherapeutic agent for treating MRSA infections.


Asunto(s)
Antibacterianos/farmacología , Erythrina , Isoflavonas/farmacología , Resistencia a la Meticilina , Fitoterapia , Extractos Vegetales/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Glucosa/metabolismo , Humanos , Isoflavonas/administración & dosificación , Isoflavonas/uso terapéutico , Leucina/metabolismo , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Staphylococcus aureus/metabolismo , Timidina/metabolismo , Uridina/metabolismo
14.
Exp Brain Res ; 158(1): 18-27, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15024541

RESUMEN

Sitting down and squatting are routine activities in daily living that lower the body mass by flexing the trunk and legs, but they obviously require different motor strategies for each goal posture. The former action must transfer the supporting surface onto a seat, whereas the latter must maintain the center of mass within the same base of both feet. By comparing the performance of both maneuvers, the mechanisms involved in initiating the downward-oriented movements and the process of optimizing the performance during their repetitions were studied. Twelve healthy subjects were asked to perform sitting-down and squatting actions immediately when a light cue was given, but at a natural speed. Electromyograms, angular movements of the joints of the right leg, and center of pressure (COP) displacement were recorded before and during each task. The initial mechanisms to initiate the break from the upright posture and the changes of postural adjustments during repetitive movements were analyzed separately. The sitting-down movement was achieved by a stereotyped motor strategy characterized by a gastrocnemius muscle burst coupled with deactivation of the erector spinae muscle. The former produced a transient COP displacement in the forward direction, and simultaneous unlocking of the trunk prevented a fall backward. By contrast, because of the absence of any need to produce momentum in a given direction, a variety of motor strategies were available to initiate squatting. The direction of initial COP displacement to initiate squatting varied with the muscles involved in unlocking the upright posture. During repetition of sitting down, the average COP position of the initial standing posture in the preparatory period was immediately shifted forward after the second trial. Simultaneously, the erector spinae muscle was deactivated earlier in the later trials. These resulted in a decreased momentum in the backward direction while the subjects were transferring themselves onto the seat. In the squatting task, however, these changes could not be identified, except for a slight flexed position of the knee during standing in the first trial. These findings suggest that in the case of transferring the body-mass to another supporting base the central nervous system immediately adjusts the size of the initial impetus to optimize the performance.


Asunto(s)
Sistema Nervioso Central/fisiología , Movimiento/fisiología , Músculo Esquelético/fisiología , Postura/fisiología , Rango del Movimiento Articular/fisiología , Potenciales de Acción/fisiología , Adulto , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos , Electromiografía , Articulación de la Cadera/fisiología , Humanos , Articulación de la Rodilla/fisiología , Pierna/inervación , Pierna/fisiología , Masculino , Contracción Muscular/fisiología , Músculo Esquelético/inervación , Orientación/fisiología , Propiocepción/fisiología
15.
Bone Marrow Transplant ; 32(4): 451-3, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12900786

RESUMEN

We report a 19-year-old man with extranodal natural killer (NK)/T cell lymphoma, nasal type treated by allogeneic peripheral blood stem cell transplantation (allo-PBSCT). His lymphoma was chemoresistant, and disseminated during local radiotherapy. The patient received allo-PBSCT from his HLA-1 locus mismatched sister using busulfan (BU), cyclophosphamide (CY) and VP-16 as the conditioning regimen. His course was complicated by esophageal actinomycosis 9 months after transplantation, which resulted in the rupture of the right common carotid artery. These observations suggest that actinomycosis should be monitored carefully after transplantation in patients who have received local radiation therapy before the procedure.


Asunto(s)
Actinomicosis/patología , Enfermedades del Esófago/patología , Linfoma de Células T/terapia , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Trasplante Homólogo/efectos adversos , Actinomicosis/etiología , Adulto , Busulfano/farmacología , Ciclofosfamida/farmacología , Etopósido/farmacología , Humanos , Inmunosupresores/farmacología , Células Asesinas Naturales/citología , Masculino , Factores de Tiempo , Acondicionamiento Pretrasplante , Trasplante Homólogo/patología
16.
Nature ; 422(6929): 284-6, 2003 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-12646914

RESUMEN

Observations of the long-lived emission--or 'afterglow'--of long-duration gamma-ray bursts place them at cosmological distances, but the origin of these energetic explosions remains a mystery. Observations of optical emission contemporaneous with the burst of gamma-rays should provide insight into the details of the explosion, as well as into the structure of the surrounding environment. One bright optical flash was detected during a burst, but other efforts have produced negative results. Here we report the discovery of the optical counterpart of GRB021004 only 193 seconds after the event. The initial decline is unexpectedly slow and requires varying energy content in the gamma-ray burst blastwave over the course of the first hour. Further analysis of the X-ray and optical afterglow suggests additional energy variations over the first few days.

17.
Bone Marrow Transplant ; 31(2): 105-11, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12621491

RESUMEN

Epstein-Barr virus (EBV)-associated T/NK-cell lymphoproliferative disease (LPD) has been linked to several different disorders, including chronic active EBV infection, EBV-associated hemophagocytic syndrome, hypersensitivity to mosquito bites, hydroa vacciniforme, aggressive NK-cell leukemia, and nasal/nasal-type NK-cell lymphoma. In most instances, these disorders are refractory to conventional treatments and have a poor prognosis. Here, we report a new treatment strategy for EBV-associated T/NK-cell LPD, consisting of immunochemotherapy, intensive combination chemotherapy, and stem cell transplantation. The five patients studied, two with T-cell and three with NK-cell LPD, lacked a human leukocyte antigen-matched, related donor, and therefore received bone marrow grafts from HLA-matched, unrelated donors. The preconditioning regimen consisted of total-body irradiation (12 Gy), etoposide (900 mg/m(2)), and cyclophosphamide (120 mg/kg) or melphalan (210 mg/m(2)). All patients had residual LPD by a quantitative PCR technique prior to transplantation. After unrelated bone marrow transplantation (UBMT), four of the five patients remain in continuous complete remission at a median of 19 months, without detectable EBV-DNA in peripheral blood. Thus, UBMT appears to be a reasonable option for the treatment of patients with EBV-associated T/NK-cell LPD. Detection of EBV-DNA by PCR offers an important tool for assessing minimal residual disease in patients with EBV-associated T/NK-cell LPD.


Asunto(s)
Trasplante de Médula Ósea/métodos , Herpesvirus Humano 4/aislamiento & purificación , Células Asesinas Naturales/inmunología , Trastornos Linfoproliferativos/terapia , Linfocitos T/inmunología , Adolescente , Niño , Preescolar , Terapia Combinada , ADN Viral/genética , ADN Viral/aislamiento & purificación , Quimioterapia Combinada , Femenino , Herpesvirus Humano 4/patogenicidad , Humanos , Células Asesinas Naturales/virología , Trastornos Linfoproliferativos/virología , Masculino , Reacción en Cadena de la Polimerasa , Linfocitos T/virología , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo , Resultado del Tratamiento
19.
Leukemia ; 16(4): 645-9, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11960345

RESUMEN

Prognostic factors of juvenile myelomonocytic leukemia (JMML) have not been clarified because of its very low incidence and inaccuracy in the diagnosis. The purpose of this study was to evaluate children with JMML given an allogeneic hematopoietic stem cell transplantation (SCT) and the role of different variables potentially influencing outcome in a nationwide survey in Japan based on the newly proposed criteria by the International JMML Working Group. The study patients were 27 children who underwent SCT among 55 JMML patients retrospectively collected in the survey. The source of grafts was HLA-identical siblings in 12 cases, HLA-matched unrelated individuals in 10 and others in five. Total body irradiation was used in 18 cases. Event-free and overall survival (OS) at 4 years after SCT were 54.2 +/- 11.2% (s.e.) and 57.9 +/- 11.0% (s.e.), respectively. Six patients died of relapse and three of complications. Patients with abnormal karyotypes showed a significantly lower OS than those with normal karyotypes (P < 0.001). Patients below 1 year of age showed a significantly higher OS than those of 1 year of age or more (P = 0.02). Patients with grade 0-1 acute graft-versus-host disease (GVHD) or chronic GVHD had a more favorable OS than those without them, although they were not statistically significant (P > 0.05). Other variables studied were not associated with OS. A multivariate analysis of these factors yielded the abnormal karyotype as the only significant risk factor for lower OS (risk ratio: 11.0; 95% CI: 2.7-45.1).


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mielomonocítica Crónica/terapia , Adolescente , Médula Ósea/patología , Niño , Preescolar , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Antígenos HLA-A/inmunología , Antígenos HLA-A/metabolismo , Humanos , Inmunosupresores/uso terapéutico , Lactante , Recién Nacido , Cariotipificación , Leucemia Mielomonocítica Crónica/diagnóstico , Leucemia Mielomonocítica Crónica/mortalidad , Masculino , Metotrexato/uso terapéutico , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Trasplante Homólogo
20.
J Immunol Methods ; 260(1-2): 195-205, 2002 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11792389

RESUMEN

We have produced a novel monoclonal antibody (mAb) directed against Wiskott-Aldrich syndrome protein (WASP) by immunizing mice with the recombinant protein. The mAb designated 5A5 is highly specific to WASP and suitable for Western blot analysis and immunoprecipitation. A flow cytometric assay using the 5A5 mAb identifies expression of intracytoplasmic WASP in lymphocytes from normal individuals. Double staining analysis with cell surface CD3, CD19, and CD56, and intracytoplasmic molecules revealed WASP expression in each subpopulation. With regard to WASP expression in patients with Wiskott-Aldrich syndrome (WAS) and X-linked thrombocytopenia (XLT), peripheral blood mononuclear cells (PBMCs) from nine patients and Epstein-Barr virus-transformed B-lymphoblastoid cell lines from seven patients examined did not show WASP expression by flow cytometric analysis. These results were confirmed by Western blot analysis. We conclude that WASP expression in lymphocyte subpopulations from patients with WAS and XLT can be more precisely evaluated by flow cytometry as compared with Western blot analysis. This flow cytometry method is important as a supplement to Western blots, but even more important as an alternative and powerful assay that can contribute to research on WASP as well as diagnosis in a clinical setting.


Asunto(s)
Citometría de Flujo/métodos , Linfocitos/metabolismo , Proteínas/análisis , Trombocitopenia/sangre , Síndrome de Wiskott-Aldrich/sangre , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/aislamiento & purificación , Línea Celular Transformada , Citoplasma/metabolismo , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Proteínas/inmunología , Proteína del Síndrome de Wiskott-Aldrich
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