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1.
Lett Appl Microbiol ; 71(1): 86-93, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31829434

RESUMEN

The purpose of this study was to find out the mechanism of quinolone resistance in Shigella sp. isolated from environmental water samples from various parts of Kolkata, India. Out of 196 Shigella sp. isolated from 2014 to 2017, we selected 32 Shigella isolates for antimicrobial susceptibility tests. The minimum inhibitory concentrations (MIC) for quinolones ranged from 30 to 50 µg ml-1 for ofloxacin, 5-20 µg ml-1 for ciprofloxacin and 20-30 µg ml-1 for norfloxacin. A few amino acid changes were found in quinolone resistance determining region (QRDR) of gyrA. Mutations in gyrA lead to a higher increment of MIC of quinolones. Among the plasmid-mediated (PMQR) quinolone resistance genes investigated, qnrB and aac(6')-lb-cr genes were found in all isolates. qnrA and qnrS were found in 25% and 62% of the isolates, respectively. ipaH gene was found in all of the isolates followed by the presence of other virulence genes ial, sen and stx1. Almost all the isolates having high MICs showed efflux pump activity in drug accumulation assay. All the mechanisms may or may not be present in a single strain. Several types of efflux pumps, presence of PMQR genes and mutations in drug target site of QRDR region may play the crucial role for resistance in our isolates.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Proteínas de Transporte de Membrana/genética , Quinolonas/farmacología , Shigella dysenteriae/genética , Shigella flexneri/genética , Ciprofloxacina/farmacología , Humanos , India , Pruebas de Sensibilidad Microbiana , Norfloxacino/farmacología , Ofloxacino/farmacología , Plásmidos/genética , Prevalencia , Shigella dysenteriae/efectos de los fármacos , Shigella dysenteriae/aislamiento & purificación , Shigella flexneri/efectos de los fármacos , Shigella flexneri/aislamiento & purificación , Virulencia
2.
Phys Chem Chem Phys ; 21(1): 260-267, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30519700

RESUMEN

We have synthesized Co3O4 nanoparticles having 40 nm average size, which are anchored on reduced graphene oxide. X-ray diffraction, FESEM, TEM and Raman spectroscopy are performed for the characterization. The temperature dependence of field cooled (FC) and zero field cooled (ZFC) magnetization curves exhibits antiferromagnetic (AFM) transition around ∼30 K, as observed for bulk Co3O4. The exchange bias effect is observed below ∼30 K. A significant change in the exchange bias effect is noted around ∼8 K, which is close to a spin-glass-like transition. The spin-glass-like phase has been confirmed by the memory effects observed by different experimental protocols. The possible origin of exchange bias is discussed in the manuscript.

3.
Ann Oncol ; 27(9): 1712-8, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27287210

RESUMEN

BACKGROUND: ARCHER 1042, a randomized phase II trial, explored the impact of prophylactic treatment on select dermatologic adverse events of interest (SDAEI), diarrhea, and mucositis associated with dacomitinib, an oral irreversible pan-human epidermal growth factor receptor (HER) inhibitor, in development for advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with advanced NSCLC treated with dacomitinib were enrolled in two cohorts. Cohort I patients were randomized 1:1 to receive oral doxycycline or placebo (4 weeks). Cohort II patients received oral VSL#3 probiotic plus topical alclometasone. Primary end points for Cohorts I and II were incidence of all grade and grade ≥2 SDAEI in the first 8 weeks of treatment and quality of life (QoL) assessed by the Skindex-16 survey. Additional primary end points for Cohort II were incidence of all grade and grade ≥2 diarrhea and mucositis in the first 8 weeks of treatment; QoL regarding diarrhea and mucositis incidence was assessed by the modified-Oral Mucositis Daily Questionnaire. RESULTS: Cohort I randomized 114 evaluable patients: 56 in the doxycycline arm, 58 in the placebo arm. Cohort II enrolled 59 evaluable patients. Doxycycline significantly reduced the incidence of grade ≥2 SDAEI by 50% (P = 0.016) compared with placebo. The incidence of all grade SDAEI was lower with doxycycline than with placebo but did not reach statistical significance. Doxycycline was associated with less deterioration in QoL compared with placebo. Alclometasone was associated with less deterioration in QoL compared with placebo but did not statistically significantly reduce the incidence of all grade or grade ≥2 SDAEI. VSL#3 did not reduce the incidence of all grade or grade ≥2 diarrhea and did not impact mucositis scores. CONCLUSIONS: Doxycycline was effective as a prophylactic treatment for dacomitinib-induced grade ≥2 SDAEI. Both doxycycline and alclometasone reduced the negative impact in patient-reported dermatologic AEs. The probiotic was not effective for preventing diarrhea or mucositis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Enfermedades Gastrointestinales/patología , Quinazolinonas/administración & dosificación , Enfermedades de la Piel/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Mutación , Calidad de Vida , Quinazolinonas/efectos adversos , Enfermedades de la Piel/inducido químicamente , Resultado del Tratamiento
4.
Ann Oncol ; 24(3): 761-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23108949

RESUMEN

BACKGROUND: An open-label, multicenter, single-arm phase II trial was conducted to investigate the clinical activity of dacomitinib in recurrent/metastatic squamous-cell carcinoma of the head and neck (RM-SCCHN). PATIENTS AND METHODS: Eligible patients were administered dacomitinib at 45 mg orally daily, in 21-day cycles. Primary end point was objective response rate. RESULTS: Sixty-nine patients were enrolled with a median age of 62 years. Among response-evaluable patients, 8 [12.7%, 95% confidence interval (CI) 5.6% to 23.5%] achieved a partial response and 36 (57.1%) had stable disease, lasting ≥24 weeks in 9 patients (14.3%). The median progression-free survival (PFS) was 12.1 weeks and the median overall survival (OS) was 34.6 weeks. Most adverse events (AEs) were tolerable. The most common grade 3 or higher treatment-related AEs were diarrhea (15.9%), acneiform dermatitis (8.7%), and fatigue (8.7%). Treatment-related AEs led to at least one dose interruption in 28 (40.6%) patients and dose reductions in 26 (37.7%). Permanent treatment discontinuation occurred in 8 (11.6%) patients due to treatment-related AEs. CONCLUSIONS: Dacomitinib demonstrated clinical activity in RM-SCCHN, and the primary end point of this study was met. The toxicity profile of this agent was generally manageable with dose interruptions and adjustments.


Asunto(s)
Antineoplásicos/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Receptores ErbB/antagonistas & inhibidores , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Quinazolinonas/administración & dosificación , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/secundario , Diarrea/inducido químicamente , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Humanos , Quimioterapia de Inducción , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Quinazolinonas/efectos adversos , Quinazolinonas/farmacocinética , Resultado del Tratamiento
5.
Oral Dis ; 14(5): 419-27, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18938267

RESUMEN

Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome that is characterized by lacey reticular hyperpigmentation of the skin, dystrophic nails, mucous membrane leukoplakia and pancytopenia. Diagnosis may be delayed until clinical signs are apparent. Severe pancytopenia frequently causes early mortality of DC patients, who have an increased risk of developing oropharyngeal squamous cell carcinoma. Several case reports have described oral changes in DC, which include oral leukoplakia, increased dental caries, hypodontia, thin enamel structure, aggressive periodontitis, intraoral brown pigmentation, tooth loss, taurodontism and blunted roots. We determined the prevalence of these previously reported findings in a cohort of 17 patients with DC and 23 family members. The most common oral changes in DC patients were oral leukoplakia (65% of the entire DC population), decreased root/crown ratio (75% with sufficient tooth development) and mild taurodontism (57% with sufficient tooth development). From the clinical perspective, a diagnosis of DC or other inherited bone marrow failure syndrome should be considered in young persons with oral leukoplakia, particularly those with no history of smoking. Multiple permanent teeth with decreased root/crown ratios further suggest DC.


Asunto(s)
Disqueratosis Congénita/complicaciones , Leucoplasia Bucal/complicaciones , Enfermedades de la Boca/complicaciones , Anomalías Dentarias/complicaciones , Adolescente , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Estudios Transversales , Índice CPO , Cavidad Pulpar/anomalías , Dentición Permanente , Familia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Odontometría , Valores de Referencia , Corona del Diente/anomalías , Raíz del Diente/anomalías
6.
Hum Gene Ther ; 12(13): 1663-72, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11535169

RESUMEN

Many nonmalignant hematologic disorders could potentially be treated by genetic correction of as few as 5-10% of target lineage cells. However, immune system clearance of cells expressing gene products perceived as foreign could be limiting. There is evidence that tolerance to foreign proteins can result when myeloablative conditioning is used, but this limits the overall applicability of such techniques. Therefore, we sought to evaluate the engraftment of hematopoietic stem cells carrying a foreign transgene after low-dose irradiation by comparing in vivo survival of murine long-term repopulating cells (LTRC) transduced with either a retroviral vector expressing the bacterial neomycin phosphotransferase gene (neo) or a vector containing neo gene sequences but modified to prevent protein expression (nonexpression). First, marrow cells from congenic donors were transduced with either vector and transplanted into recipients treated with standard dose irradiation of 800 rads. High-level engraftment and gene marking resulted, without differences in the marking levels or pattern of persistence of the cells between cells transduced with either vector. Low-dose irradiation at 100 rads was tested using higher cell doses. Marking levels as high as 10% overall were obtained, again with no differences between mice receiving cells transduced with the neo versus the nonexpression vectors. To investigate a potentially more immunogenic protein, marrow cells were transduced with a vector containing the green fluorescent protein (GFP) gene, and their persistence was studied in recipient mice receiving 100 rads. Stable GFP expression in 5-10% of circulating cells was observed long term. We conclude that even with very low dose conditioning, engraftment by genetically modified LTRC cells at clinically significant levels can be achieved without evidence for clearance of cells known to be expressing immunogenic proteins.


Asunto(s)
Supervivencia de Injerto , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/citología , Células Mieloides/efectos de la radiación , Retroviridae/genética , Transducción Genética , Transgenes/genética , Animales , Animales Congénicos , Línea Celular , Supervivencia Celular , Femenino , Citometría de Flujo , Expresión Génica , Vectores Genéticos/genética , Supervivencia de Injerto/genética , Supervivencia de Injerto/inmunología , Proteínas Fluorescentes Verdes , Células Madre Hematopoyéticas/inmunología , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/efectos de la radiación , Humanos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/inmunología , Ratones , Ratones Endogámicos C57BL , Quimera por Radiación/genética , Quimera por Radiación/inmunología , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
7.
Exp Hematol ; 29(6): 779-85, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11378274

RESUMEN

OBJECTIVE: Previous studies have shown improved engraftment in a murine model when granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF) were administered for 5 days prior to irradiation, with significant levels of engraftment in the growth factor-preconditioned group even at very low radiation doses. We sought to explore the mechanisms behind this effect. METHODS: The radiation sensitivity of mice with or without 5 days of prestimulation with G-CSF (200 microg/kg/d) and SCF (50 microg/kg/d) was compared. To further evaluate whether growth factor prestimulation enhances engraftment by mobilization of hematopoietic progenitors into peripheral blood, thus creating less endogenous competition within the marrow compartment, female mice were pretreated with 5 days of G-CSF/SCF or control diluent. Engraftment of 40 x 10(6) peripheral blood stem cells (PBSCs) harvested from G-CSF/SCF-mobilized male mice was compared in the two recipient groups. RESULTS: There was no difference in survival between the pretreated and control mice at the radiation doses tested. Additionally, there was no significant difference in the recovery of blood counts, bone marrow cellularity, colony-forming unit (CFU) content, or stem cell numbers assessed 4 months later in a competitive repopulation model. Engraftment levels of male cells did not differ between G-CSF/SCF-pretreated and control recipients, and could be detected in 30% of recipients at 20-24 weeks (4/12 in each group) at overall levels of 0.1-1%. CONCLUSIONS: The enhanced engraftment in cytokine pretreated recipients is unlikely to be due to increased endogenous stem-cell killing or to the creation of endogenous marrow "space" by egress of endogenous stem cells after cytokine prestimulation.


Asunto(s)
Células de la Médula Ósea/citología , Factor Estimulante de Colonias de Granulocitos/farmacología , Células Madre Hematopoyéticas/citología , Factor de Células Madre/farmacología , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Femenino , Movilización de Célula Madre Hematopoyética , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/efectos de la radiación , Humanos , Recuento de Leucocitos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos , Ratas , Proteínas Recombinantes/farmacología , Irradiación Corporal Total
8.
Mol Ther ; 1(6): 533-44, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10933978

RESUMEN

Host immune responses against foreign transgenes may be a major obstacle to successful gene therapy. To clarify the impact of an immune response to foreign transgene products on the survival of genetically modified cells, we studied the in vivo persistence of cells transduced with a vector expressing a foreign transgene compared to cells transduced with a nonexpressing vector in the clinically predictive rhesus macaque model. We constructed retroviral vectors containing the neomycin phosphotransferase gene (neo) sequences modified to prevent protein expression (nonexpressing vectors). Rhesus monkey lymphocytes or hematopoietic stem cells (HSCs) were transduced with nonexpressing and neo-expressing vectors followed by reinfusion, and their in vivo persistence was studied. While lymphocytes transduced with a nonexpressing vector could be detected for more than 1 year, lymphocytes transduced with a neo-expressing vector were no longer detectable within several weeks of infusion. However, five of six animals transplanted with HSCs transduced with nonexpression or neo-expression vectors, and progeny lymphocytes marked with either vector persisted for more than 2 years. Furthermore, in recipients of transduced HSCs, infusion of mature lymphocytes transduced with a second neo-expressing vector did not result in elimination of the transduced lymphocytes. Our data show that introduction of a xenogeneic gene via HSCs induces tolerance to the foreign gene products. HSC gene therapy is therefore suitable for clinical applications where long-term expression of a therapeutic or foreign gene is required.


Asunto(s)
Células Madre Hematopoyéticas/inmunología , Células Madre Hematopoyéticas/metabolismo , Tolerancia Inmunológica , Animales , Secuencia de Bases , Transfusión de Sangre Autóloga , Cartilla de ADN/genética , Expresión Génica , Terapia Genética/métodos , Vectores Genéticos , Trasplante de Células Madre Hematopoyéticas , Kanamicina Quinasa/genética , Kanamicina Quinasa/inmunología , Transfusión de Linfocitos , Linfocitos/inmunología , Linfocitos/metabolismo , Macaca mulatta , Modelos Biológicos , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Transducción Genética , Trasplante Autólogo
9.
J Infect Dis ; 182(1): 274-82, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10882607

RESUMEN

The central nervous system (CNS) distribution and antifungal efficacy of all 4 approved formulations of amphotericin B (AmB) were investigated in a rabbit model of hematogenous Candida albicans meningoencephalitis. Treatment with AmB deoxycholate (1 mg/kg/day) or liposomal AmB (5 mg/kg/day) yielded the highest peak plasma concentration (C(max)), area under concentration versus time curve from zero to 24 h (AUC(0-24)), and time during dosing level tau Ttau>minimum inhibitory complex (MIC) values and led to complete eradication of C. albicans from brain tissue (P<.05 vs. untreated controls). By comparison, AmB colloidal dispersion and AmB lipid complex (5 mg/kg/day each) were only partially effective (not significant vs. untreated controls). There was a strong correlation of C(max), AUC(0-24), C(max)/MIC, AUC(0-24)/MIC, and Ttau>MIC with clearance of C. albicans from brain tissue (P

Asunto(s)
Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Candida albicans/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Infecciones Fúngicas del Sistema Nervioso Central/tratamiento farmacológico , Anfotericina B/administración & dosificación , Anfotericina B/sangre , Animales , Antifúngicos/administración & dosificación , Antifúngicos/sangre , Candidiasis/sangre , Candidiasis/metabolismo , Infecciones Fúngicas del Sistema Nervioso Central/sangre , Infecciones Fúngicas del Sistema Nervioso Central/microbiología , Química Farmacéutica , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Femenino , Lípidos/química , Pruebas de Sensibilidad Microbiana , Conejos , Resultado del Tratamiento
10.
Br J Haematol ; 108(1): 167-75, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10651740

RESUMEN

Diamond-Blackfan anaemia (DBA) is a constitutional pure red cell aplasia presenting in early childhood. In some patients, neutropenia and/or thrombocytopenia have also been observed during the course of the disease. We have followed 28 patients with steroid-refractory DBA for up to 13 years with serial peripheral blood counts and bone marrow (BM) aspirates and biopsies. In 21/28 (75%) patients, moderate to severe generalized BM hypoplasia developed, with overall cellularities ranging from 0% to 30%. Marrow hypoplasia correlated with the development of neutropenia (9/21; 43%) and/or thrombocytopenia (6/21; 29%) in many patients. No patient had either cytogenetic abnormalities or progressed to acute leukaemia, although one 13-year-old developed marked marrow fibrosis and trilineage dysplasia. We used the in vitro long-term culture-initiating cell (LTC-IC) assay to quantify multilineage, primitive haematopoietic progenitors in a representative subset of these patients. LTC-IC assays showed equivalent frequencies of cobblestone area-forming cells (CAFCs) with a mean of 5.42/10(5) cells +/- 1.9 SD and 6.13/10(5) cells +/- 2.6 SD in nine patients and six normal controls respectively. The average clonogenic cell output per LTC-IC, however, was significantly lower in DBA patients (mean 2.16 +/- 1.2 SD vs. 7. 36 +/- 2.7 SD in normal controls, P = 0.0008). Our results suggest that the underlying defect in patients with severe refractory DBA may not be limited to the erythroid lineage, as was evidenced by the development of pancytopenia, bone marrow hypoplasia and reduced clonogenic cell output in LTC-IC assays.


Asunto(s)
Anemia de Fanconi/patología , Adolescente , Adulto , Células de la Médula Ósea/patología , Células Cultivadas , Niño , Preescolar , Enfermedad Crónica , Anemia de Fanconi/terapia , Femenino , Hematopoyesis/fisiología , Humanos , Lactante , Recién Nacido , Masculino , Neutropenia/etiología , Neutropenia/patología , Trombocitopenia/etiología , Trombocitopenia/patología
11.
J Antimicrob Chemother ; 43(1): 95-103, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10381106

RESUMEN

The activity of liposomal nystatin against invasive pulmonary aspergillosis was investigated in persistently neutropenic rabbits. Treatment groups included liposomal nystatin at dosages of 1, 2 and 4 mg/kg/day intravenously, or amphotericin B deoxycholate 1 mg/kg/day administered intravenously after normal saline loading. As compared with untreated controls, liposomal nystatin administered at 2 and 4 mg/kg/day prolonged survival and reduced fungus-mediated tissue injury and excess lung weight at post-mortem in a similar manner to amphotericin B. Although amphotericin B was superior in clearing infected lung tissue, treatment with all regimens of liposomal nystatin led to a significant reduction in pulmonary fungal tissue burden. During treatment, ultrafast CT-scan demonstrated ongoing resolution of pulmonary lesions at 2 and 4 mg/kg/day, but not at 1 mg/kg/day. With the exception of mild increases in blood urea nitrogen (BUN) and serum creatinine values during treatment at 2 and 4 mg/kg/day, which were similar to those found in amphotericin B-treated rabbits, liposomal nystatin was well tolerated. Preliminary pharmacokinetic studies in non-infected animals established linear drug disposition of liposomal nystatin in plasma over the investigated dosage range and peak plasma levels above the MIC for the test strain after multiple daily dosing for 7 days. Liposomal nystatin increased survival and provided reduced tissue injury, effective microbiological clearance and tolerable side effects in experimental pulmonary aspergillosis in persistently neutropenic rabbits, thus providing a rational basis for further investigations in clinical trials.


Asunto(s)
Antifúngicos/farmacología , Aspergilosis/tratamiento farmacológico , Enfermedades Pulmonares Fúngicas/tratamiento farmacológico , Neutropenia/complicaciones , Nistatina/farmacología , Anfotericina B/farmacología , Animales , Antifúngicos/sangre , Antifúngicos/toxicidad , Área Bajo la Curva , Aspergilosis/microbiología , Aspergilosis/mortalidad , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Portadores de Fármacos , Femenino , Semivida , Liposomas , Pulmón/diagnóstico por imagen , Pulmón/microbiología , Pulmón/patología , Enfermedades Pulmonares Fúngicas/microbiología , Enfermedades Pulmonares Fúngicas/mortalidad , Nistatina/sangre , Nistatina/toxicidad , Tamaño de los Órganos/efectos de los fármacos , Conejos , Radiografía , Tasa de Supervivencia
12.
Antimicrob Agents Chemother ; 42(10): 2700-5, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9756780

RESUMEN

The pharmacokinetics of the antifungal pradimicin derivative BMS 181184 in plasma of normal, catheterized rabbits were characterized after single and multiple daily intravenous administrations of dosages of 10, 25, 50, or 150 mg/kg of body weight, and drug levels in tissues were assessed after multiple dosing. Concentrations of BMS 181184 were determined by a validated high-performance liquid chromatography method, and plasma data were modeled into a two-compartment open model. Across the investigated dosage range, BMS 181184 demonstrated nonlinear, dose-dependent kinetics with enhanced clearance, reciprocal shortening of elimination half-life, and an apparently expanding volume of distribution with increasing dosage. After single-dose administration, the mean peak plasma BMS 181184 concentration (Cmax) ranged from 120 microg/ml at 10 mg/kg to 648 microg/ml at 150 mg/kg; the area under the concentration-time curve from 0 to 24 h (AUC0-24) ranged from 726 to 2,130 microg . h/ml, the volume of distribution ranged from 0.397 to 0.799 liter/kg, and the terminal half-life ranged from 4.99 to 2.31 h, respectively (P < 0.005 to P < 0.001). No drug accumulation in plasma occurred after multiple daily dosing at 10, 25, or 50 mg/kg over 15 days, although mean elimination half-lives were slightly longer. Multiple daily dosing at 150 mg/kg was associated with enhanced total clearance and a significant decrease in AUC0-24 below the values obtained at 50 mg/kg (P < 0.01) and after single-dose administration of the same dosage (P < 0.05). Assessment of tissue BMS 181184 concentrations after multiple dosing over 16 days revealed substantial uptake in the lungs, liver, and spleen and, most notably, dose-dependent accumulation of the drug within the kidneys. These findings are indicative of dose- and time-dependent elimination of BMS 181184 from plasma and renal accumulation of the compound after multiple dosing.


Asunto(s)
Antraciclinas , Antibióticos Antineoplásicos/farmacocinética , Antifúngicos/farmacocinética , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/toxicidad , Femenino , Conejos , Distribución Tisular
13.
Antimicrob Agents Chemother ; 42(9): 2399-404, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9736570

RESUMEN

The activity of the pradimicin derivative BMS 181184 was evaluated in a model of invasive pulmonary aspergillosis in persistently neutropenic rabbits and compared with that of amphotericin B deoxycholate. BMS 181184 at total daily doses of 50 and 150 mg/kg of body weight was at least as effective as amphotericin B at 1 mg/kg once a day in conferring survival and had comparable activity in reducing organism-mediated tissue injury and excess lung weight. Although treatment at all dosing regimens of BMS 181184 resulted in significant reductions in fungal tissue burden compared to untreated controls, equivalence to amphotericin B occurred only at the higher dosage level. Similar observations were made in bronchoalveolar lavage fluid cultures obtained postmortem. Monitoring of the animals through ultrafast computerized tomography scan revealed a marked resolution of pulmonary lesions during treatment with BMS 181184. The compound was well tolerated at all dosing regimens, and no toxicity was noted. Pharmacokinetic studies revealed nonlinear drug disposition with increased clearance at higher dosages and some evidence for extravascular drug accumulation. BMS 181184 had excellent activity in the treatment of experimental invasive pulmonary aspergillosis in persistently neutropenic rabbits, thus underscoring the potential of pradimicin derivatives in therapy of invasive aspergillosis in the neutropenic host.


Asunto(s)
Antraciclinas , Antibióticos Antineoplásicos/uso terapéutico , Antifúngicos/uso terapéutico , Aspergilosis/tratamiento farmacológico , Enfermedades Pulmonares Fúngicas/tratamiento farmacológico , Animales , Antibióticos Antineoplásicos/efectos adversos , Antibióticos Antineoplásicos/farmacocinética , Aspergilosis/microbiología , Aspergilosis/patología , Enfermedades Pulmonares Fúngicas/microbiología , Enfermedades Pulmonares Fúngicas/patología , Conejos
14.
Pediatr Infect Dis J ; 16(2): 216-21, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9041604

RESUMEN

BACKGROUND: Aspergillosis is an uncommon yet serious opportunistic infection in patients with AIDS. It has been extensively reported in HIV-infected adult patients. To our knowledge there are no studies that describe the epidemiology, clinical manifestations and outcome of aspergillosis in a large HIV-infected pediatric population. METHODS: We reviewed the records of all 473 HIV-infected children followed in the Pediatric Branch of the National Cancer Institute for 9 years from 1987 through 1995 for the presence of Aspergillus infection. RESULTS: Seven (1.5%) patients developed invasive aspergillosis during the study period. All patients had low CD4 counts reflecting severe immunosuppression. Sustained neutropenia (> 7 days) or corticosteroid therapy as a predisposing factor for invasive aspergillosis was encountered in only two patients (28%). Invasive pulmonary aspergillosis developed in five patients and cutaneous aspergillosis in two. The most common presenting features in patients with pulmonary aspergillosis were fever, cough and dyspnea. Patients with cutaneous aspergillosis were diagnosed during life and successfully treated with amphotericin B and surgery, whereas diagnosis of pulmonary aspergillosis was made clinically in only one patient. CONCLUSIONS: Aspergillosis is an uncommon but highly lethal opportunistic infection in HIV-infected children. Invasive pulmonary aspergillosis should be considered in the differential diagnosis in febrile, HIV-infected children with persistent pulmonary infiltrates.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA , Aspergilosis , Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/fisiopatología , Adolescente , Antifúngicos/uso terapéutico , Aspergilosis/diagnóstico , Aspergilosis/tratamiento farmacológico , Aspergilosis/epidemiología , Aspergilosis/fisiopatología , Recuento de Linfocito CD4 , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/microbiología , Humanos , Lactante , Masculino , Neutropenia , Estudios Retrospectivos
15.
Pediatr Hematol Oncol ; 14(1): 73-7, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9021816

RESUMEN

Thirteen children older than 3 years of age with beta-thalassemia major underwent allogeneic bone marrow transplantation (BMT) from a full human leukocyte antigen (HLA) matched sibling donor in a single institution. These patients received busulfan (Bu). 16 mg/kg followed by cyclophosphamide (Cy) 200 mg/kg for conditioning. Eight of the 13 patients (Group 1) engrafted and have a median age of 13 years (range 5-15 years). The five patients (Group 2) who failed to engraft have a median age of 6 years (range 3-8 years). The association with the following factors was found to be statistically significant: age (older in Group 1), duration of nadir of white blood count (WBC) of < or = .1 x 10(9)/L (longer in Group 1), and the dose of Bu administered to each patient calculated on the basis of body surface area (higher dose in Group 1). The high rate of engraftment failure (5 out of 13) may be related to the suboptimal systemic exposure of Bu in younger children leading to inadequate bone marrow ablation when the standard dose of 16 mg/kg is used.


Asunto(s)
Trasplante de Médula Ósea , Busulfano/uso terapéutico , Ciclofosfamida/uso terapéutico , Rechazo de Injerto , Inmunosupresores/uso terapéutico , Acondicionamiento Pretrasplante/métodos , Talasemia beta/terapia , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios Retrospectivos , Estadísticas no Paramétricas
16.
Eur J Clin Microbiol Infect Dis ; 16(1): 93-7, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9063679

RESUMEN

Pradimicins are a new class of antifungal compounds currently undergoing preclinical and early phase I clinical trials. The pradimicin structure is characterized by an aglycone of dihydrobenzo (alpha) naphthacenequinone with substitutions by a D-amino acid and hexose sugar. Pradimicins possess a novel mechanism of action consisting of a specific binding recognition to terminal D-mannosides of the cell wall of Candida albicans, resulting in the formation of a ternary complex consisting of D-mannoside, pradimicin, and calcium that leads to disruption of the integrity of the fungal cell membrane. Pradimicin in the form of BMS-181184 has broad-spectrum in vitro antifungal activity against Candida spp., Cryptococcus neoformans, Aspergillus spp., dematiaceous molds, and the Zygomycetes. Fusarium spp. are comparatively resistant to high concentrations of pradimicin. Initial vivo studies indicate that pradimicins have antifungal activity against experimental murine disseminated candidiasis and disseminated aspergillosis. Early studies indicate an excellent therapeutic index with no major end-organ toxicity. Pradimicins warrant further investigation for treatment of opportunistic mycoses in immuno-compromised hosts.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Antifúngicos/uso terapéutico , Antibióticos Antineoplásicos/uso terapéutico , Antifúngicos/efectos adversos , Antifúngicos/farmacología , Fenómenos Químicos , Química , Humanos , Micosis/tratamiento farmacológico , Relación Estructura-Actividad
17.
Bone Marrow Transplant ; 18(3): 489-94, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8879607

RESUMEN

Children with acute lymphoblastic leukemia (ALL) undergoing allogeneic bone marrow transplantation (BMT) using total body irradiation (TBI)-containing conditioning regimens are at risk of substantial late sequelae affecting growth and endocrine functions. This has lead to the use of non-TBI or chemotherapy conditioning regimens for ALL patients in many centers. However, it is unknown whether chemotherapy conditioning results in improved antileukemic efficacy or reduced transplant-related toxicity. We report our experience using a chemotherapy conditioning regimen (busulfan (Bu), cyclophosphamide (CY) and melphalan (Mel)) in 26 consecutively enrolled children with ALL (group I). At a median follow-up of 58 months, event-free survival (EFS) for Bu/CY/Mel-treated patients was 27% (+/- 8.7), while the leukemic relapse rate was 49% (+/- 13). Regimen-related toxicity was severe in these patients: overall treatment-related mortality was 42%, while 50% of patients had interstitial pneumonitis and 35% of patients had severe hemorrhagic cystitis. A historical control group of 25 consecutively enrolled patients, mostly treated with TBI-containing regimens (group II), had an EFS of 36% (+/- 9.6%) and a leukaemic relapse rate of 45% (+/- 11) at a median follow-up of 117 months. We conclude that the Bu/CY/Mel conditioning regimen leads to severe transplant-related toxicity and did not significantly improve leukemic relapse rates.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Acondicionamiento Pretrasplante , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Busulfano/administración & dosificación , Niño , Preescolar , Ciclofosfamida/administración & dosificación , Humanos , Lactante , Melfalán/administración & dosificación , Trasplante Homólogo
18.
J Pediatr Hematol Oncol ; 17(4): 350-5, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7583393

RESUMEN

PURPOSE: Most patients diagnosed with malignant osteopetrosis die during infancy or early childhood from hemorrhage and infection due to bone marrow failure. Allogeneic bone marrow transplantation (BMT) has been reported to provide curative therapy for this disorder. We report our experience with eight patients with malignant osteopetrosis who underwent BMT. PATIENTS AND METHODS: Between May 1987 and August 1992, eight children with malignant osteopetrosis underwent allogeneic BMT. Median age at BMT was 9 months (range, 2-36 months). Six patients received marrow from HLA-identical sibling donors, one from phenotypically matched father, and one from a one antigen mismatched father. BMT conditioning for all patients was busulfan 16 mg/kg and cyclophosphamide 200 mg/kg each administered over 4 days. Graft versus host disease (GVHD) prophylaxis included cyclosporin A in six patients or cyclosporin A and methotrexate in two patients. RESULTS: Six patients, including those who received bone marrow from their father's, engrafted as documented by bone marrow biopsy showing an increase in osteoclasts in all cases and by chromosomal analysis in four patients. Two patients died without engraftment. Three out of six patients engrafted are alive and well at the follow-up of 48, 63, and 81 months. Serum calcium, alkaline, and acid phosphatase levels normalized within 2 months. These patients have full bone marrow reconstitution. Serial radiologic studies revealed bone marrow remodelling and a new nonsclerotic bone formation. Vision improved dramatically in the youngest patient. CONCLUSION: BMT offers cure to patients with malignant osteopetrosis with reconstitution of bone marrow and correction of metabolic disturbances. In our experience, reversibility in neurosensory deficit is possible when BMT is done at an early age.


Asunto(s)
Trasplante de Médula Ósea , Osteopetrosis/terapia , Huesos/diagnóstico por imagen , Huesos/patología , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Osteopetrosis/diagnóstico por imagen , Osteopetrosis/patología , Radiografía
19.
Aust N Z J Med ; 24(1): 26-30, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8002854

RESUMEN

BACKGROUND: Bone marrow transplantation (BMT) is usually the only procedure offering cure for children with life-threatening immune deficiency disorders, but compatible sibling donors are frequently unavailable. AIMS AND METHODS: To examine the outcome of HLA non-identical T-cell-depleted BMT carried out between April 1985 and May 1992 in 11 patients with primary immunodeficiency diseases and to seek prognostic factors. RESULTS: Eight patients achieved sustained engraftment, one after a second BMT. One further patient engrafted transiently, but rejected the graft five months later. Acute graft-versus-host disease (GVHD) grade II was seen in one and chronic GVHD was seen in three children. Seven patients survived beyond six months, six with donor T cell and five with donor B cell engraftment. At present, five patients (46%) are alive with immune reconstitution at a median follow-up of 14 months (range 6 to 78 months). The major factor associated with outcome was the presence of any infection within one week of BMT (p = 0.01). The presence of lung infection also tended to be a poor prognostic factor (p = 0.06) but did not reach significance, presumably because of the small sample size. HLA non-identical (parental) T-cell depleted BMT plays an important role in the cure of children with immunodeficiencies who do not have an identical sibling donor. Survival can be further improved if the diagnosis of immunodeficiency disease is made early and BMT undertaken before significant infections occur. CONCLUSIONS: The availability of T-cell depleted haploidentical parental bone marrow transplant can be anticipated to improve outcome significantly for children with severe immunodeficiency, especially when diagnosed early.


Asunto(s)
Trasplante de Médula Ósea , Antígenos HLA/análisis , Depleción Linfocítica , Inmunodeficiencia Combinada Grave/terapia , Linfocitos T , Niño , Preescolar , Femenino , Estudios de Seguimiento , Enfermedad Injerto contra Huésped/epidemiología , Humanos , Lactante , Masculino , Pronóstico , Estudios Retrospectivos , Inmunodeficiencia Combinada Grave/mortalidad , Factores de Tiempo , Quimera por Trasplante
20.
Bone Marrow Transplant ; 12(4): 347-50, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8275033

RESUMEN

Permanent alopecia after BMT has been reported as a side-effect associated with GVHD or after busulphan conditioning therapy, primarily in adults. We have reviewed children undergoing BMT to document the frequency of incomplete hair regrowth and to evaluate factors associated with this problem. Hair regrowth was studied in 74 children who survived > 6 months following BMT undertaken for malignant and non-malignant diseases. Alopecia was categorised as severe (< 50% of pre-transplant status), moderate (50-75%) or mild (> 75% but less than normal). Overall, 18 (24.3%) of 74 patients had mild (n = 5), moderate (n = 4) or severe (n = 9) alopecia. Risk factors for alopecia were presence of chronic GVHD (67%; p < 0.001), older age (p < 0.001) and prior cranial irradiation (42%; p = 0.03). Alopecia occurred in children receiving either busulphan (31%) or total body irradiation (16%; p = 0.15) as conditioning therapy. The highest frequency was seen in patients conditioned with busulphan with or without melphalan and who received prior cranial irradiation and/or developed chronic GVHD (75%). These data indicate that alopecia after BMT in children is a significant problem and confirm, in children, the previously noted association between alopecia and chronic GVHD and busulphan. Further risk factors of older age and prior cranial irradiation are identified. Consideration needs to be given to the use of an alternative to busulphan in children who are of older age, have received prior cranial irradiation and/or are at increased risk of GVHD.


Asunto(s)
Alopecia/fisiopatología , Purgación de la Médula Ósea/efectos adversos , Trasplante de Médula Ósea , Busulfano/efectos adversos , Enfermedad Injerto contra Huésped/complicaciones , Cabello/fisiopatología , Irradiación Corporal Total , Adolescente , Adulto , Factores de Edad , Alopecia/inducido químicamente , Alopecia/etiología , Trasplante de Médula Ósea/efectos adversos , Preescolar , Enfermedad Crónica , Irradiación Craneana/efectos adversos , Femenino , Humanos , Lactante , Leucemia/cirugía , Masculino , Melfalán , Traumatismos por Radiación/fisiopatología , Factores de Riesgo
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