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1.
J Microsc ; 278(2): 76-88, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32144777

RESUMEN

The applicability of confocal laser scanning microscopy is limited, e.g. by attenuation of the excitation and the fluorescence emission beam. As a prerequisite for further processing and analysis of the obtained microscopic images, a new method is presented for correcting this attenuation. The correction is based on beam modelling and on a differential form of the modified Beer-Lambert law. It turns out that the intensity decay can be modelled as a double convolution of the microscopic image with the intensities of the excitation semibeam and the emission beam. Under weak assumptions made for the intensities of the fluorescent radiation and the detected signal, formulas for the attenuation correction and the attenuation simulation are derived. The method traces back to that one published by Roerdink which is modified concerning a more realistic beam modelling, avoiding the so-called weak attenuation expansion and considering fluorescence excitation throughout the light cone of the excitation beam. The applicability of the method is demonstrated for synthetic examples as well as microscopic images of chromatographic beads. It is shown that the new method can be successfully applied for reconstructing the true fluorophore distribution in specimens even if the microscopic images are affected by strong attenuation. LAY DESCRIPTION: The applicability of confocal laser scanning microscopy is limited by attenuation of the excitation and the fluorescence emission beam. As a prerequisite for further processing and analysis of the obtained microscopic images, a new method is presented for correcting this attenuation. The correction is based on modeling the excitation as well as the emission beam and on a modified Beer-Lambert law for beam attenuation. The applicability of the method is demonstrated for synthetic examples as well as microscopic images of chromatographic beads. It is shown that the new method can be successfully applied for reconstructing the true fluorophore distribution in specimens even if the microscopic images are affected by strong attenuation.

2.
J Antimicrob Chemother ; 70(10): 2894-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26163402

RESUMEN

OBJECTIVES: Aspergillus fumigatus is the leading cause of invasive aspergillosis. Adequate treatment is complicated by an increase in azole resistance. Here, the incidence of voriconazole, posaconazole and itraconazole resistance in clinical isolates from high-risk patients from either the haematology ward or the ICU of the University Medical Center Utrecht in the period 2011-13 is analysed. Putative clonality of resistant strains was tested through cyp51A and microsatellite typing. METHODS: Primary A. fumigatus isolates from 105 patients were collected by an unbiased routine diagnostic-driven approach and phenotypically tested for azole susceptibility. Of the 105 isolates, 5 were from patients with a proven invasive A. fumigatus infection, 48 were from patients with a probable invasive A. fumigatus infection and 52 were from patients with non-invasive infections. Real-time PCR and cyp51A gene and strain typing were performed. RESULTS: Twenty-one out of 105 (20.0%) isolates were resistant to at least one of the three clinical azoles and 17/105 (16.2%) isolates were resistant (MIC >2 mg/L) to voriconazole, the empirical drug of choice for treatment of aspergillosis. There was a striking difference in the prevalence of triazole resistance, with 15.9% resistant isolates (25.0% in proven/probable patients) in the haematology population and 4.5% (10% in proven/probable) in the ICU. While the majority of isolates with elevated MICs of voriconazole were cyp51A related (17/23), both microsatellite and cyp51A sequence typing argue against clonal spread of resistant strains. CONCLUSIONS: This study reveals a high incidence of voriconazole resistance (16.2%) in A. fumigatus in high-risk patients. Our data stress the need for laboratory detection of azole resistance prior to treatment.


Asunto(s)
Antifúngicos/farmacología , Aspergilosis/epidemiología , Aspergilosis/microbiología , Aspergillus fumigatus/efectos de los fármacos , Azoles/farmacología , Farmacorresistencia Fúngica , Centros Médicos Académicos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aspergilosis/diagnóstico , Aspergilosis/tratamiento farmacológico , Aspergillus fumigatus/genética , Aspergillus fumigatus/aislamiento & purificación , Niño , Preescolar , Infección Hospitalaria , Sistema Enzimático del Citocromo P-450/genética , ADN de Hongos , Femenino , Proteínas Fúngicas/genética , Humanos , Incidencia , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Repeticiones de Microsatélite , Persona de Mediana Edad , Tipificación Molecular , Filogenia , Prevalencia , Adulto Joven
3.
Int J Tuberc Lung Dis ; 27(8): 612-618, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37491746

RESUMEN

SETTING: Tertiary level hospital in Lusaka, Zambia.OBJECTIVE: To measure concordance between Xpert® MTB/RIF Ultra (Ultra) results of stool with and without transport media, and compare Ultra results from the two stool processing methods to Ultra and culture results using gastric aspirates (GA).DESIGN: This was a cross-sectional study collecting stool and GA from children 0-5 years presenting with signs and symptoms of TB. Stool was processed for Ultra testing by two methods: the Simple-One-Step (SOS) on an aliquot of stool and PrimeStore® MTM Molecular Transport Medium (PS-MTM) using a stool swab.RESULTS: A total of 114 children (median age: 17 months, IQR 7-30) provided both a stool and a GA sample. Stool Ultra results processed using the PS-MTM method showed high concordance with stool Ultra results processed by the SOS method, with only 1/114 discordant results. Concordance with GA Ultra was high as well, as 9/13 Mycobacterium tuberculosis (MTB) cases detected were identified by all three methods.CONCLUSION: Ultra results from stool swabs collected using PS-MTM were equivalent to results from stool using the SOS method and GA. Given that PS-MTM inactivates MTB and stabilises DNA without cold chain, using it for stool has the potential to increase access to a TB diagnosis for children in underserved areas.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Pulmonar , Humanos , Niño , Lactante , Tuberculosis Pulmonar/diagnóstico , Estudios Transversales , Sensibilidad y Especificidad , Zambia , Esputo/microbiología , Mycobacterium tuberculosis/genética
4.
Int J Tuberc Lung Dis ; 27(1): 19-27, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36853124

RESUMEN

SETTING: In 2020, the National TB Programme (NTP) of Vietnam conducted an implementation pilot of the Simple One-Step (SOS) stool processing method using Xpert® MTB/RIF Ultra (Ultra) among children and people living with HIV (PLHIV) with signs and symptoms of TB.DESIGN and OBJECTIVES: Using data from this pilot and collecting information on healthcare workers´ (HCWs) perceptions, we assessed the feasibility, acceptability and potential impact of routine stool testing for TB.RESULTS: HCWs perceived collection of stools from children as least stressful of all sample types, stool processing as acceptable and the SOS stool method as easy to perform. After a 3-month induction period, the proportion of initial non-determinate Ultra stool tests was less than 5%. Combined Ultra testing of a respiratory sample and stool resulted in an increase in the proportion of bacteriologically confirmed TB among PLHIV and children by respectively 4.1% (95% CI 1.6-6.6) and 3.9% (95% CI 1.6-6.2). Among children, Mycobacterium tuberculosis was more often detected in stool (26.1%) than in respiratory samples (23.4%) (P = 0.06), including one child with rifampicin resistance.CONCLUSION: Stool testing can be feasibly implemented both in adult PLHIV and in children in routine settings, providing a non-invasive alternative sample type for the diagnosis of TB for patients who cannot produce sputum.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Adulto , Niño , Humanos , Heces , Rifampin , Esputo , Tuberculosis/diagnóstico
5.
Knee Surg Sports Traumatol Arthrosc ; 20(2): 223-31, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21750950

RESUMEN

PURPOSE: The purpose of this study was to investigate the influence of continuous perfusion and mechanical stimulation on bone marrow stromal cells seeded on a collagen meniscus implant. METHODS: Bone marrow aspirates from 6 donors were amplified in vitro. 10(6) human BMSC were distributed on a collagen meniscus implant. Scaffolds were cultured under static conditions (control) or placed into a bioreactor system where continuous perfusion (10 ml/min) or perfusion and mechanical stimulation (8 h of 10% cyclic compression at 0.5 Hz) were administered daily. After 24 h, 7 and 14 days, cell proliferation, synthesis of procollagen I and III peptide (PIP, PIIIP), histology, and the equilibrium modulus of the constructs were analyzed. RESULTS: Proliferation demonstrated a significant increase over time in all groups (p < 0.001). PIP synthesis was found to increase from 0.1 ± 0.0 U/ml/g protein after 24 h to 2.0 ± 0.5 (perfusion), 3.8 ± 0.3 (mechanical stimulation), and 1.8 ± 0.2 U/ml/g protein (static control, lower than perfusion and mechanical stimulation, p < 0.05). These differences were also evident after 2 weeks (2.7 ± 0.3, 4.0 ± 0.6, and 1.8 ± 0.2 U/ml/g protein, p < 0.01); PIIIP synthesis was found to increase from 0.1 ± 0.0 U/ml/g protein after 24 h to 2.9 ± 0.7 (perfusion), 3.1 ± 0.9 (mechanical stimulation), and 1.6 ± 0.3 U/ml/g protein (controls) after 1 week and remained significantly elevated under the influence of perfusion and mechanical stimulation (p < 0.01) after 2 weeks. Mechanical stimulation increased the equilibrium modulus more than static culture and perfusion after 2 weeks (24.7 ± 7.6; 12.3 ± 3.7; 15.4 ± 2.6 kPa; p < 0.02). CONCLUSION: Biomechanical stimulation and perfusion have impact on collagen scaffolds seeded with BMSCs. Cell proliferation can be enhanced using continuous perfusion and differentiation is fostered by mechanical stimulation.


Asunto(s)
Colágeno , Meniscos Tibiales , Perfusión , Ingeniería de Tejidos , Andamios del Tejido , Fenómenos Biomecánicos , Reactores Biológicos , Células de la Médula Ósea/fisiología , Proliferación Celular , Células Cultivadas , Colágeno/metabolismo , Humanos , Meniscos Tibiales/citología , Meniscos Tibiales/metabolismo , Meniscos Tibiales/fisiología , Presión , Procolágeno/metabolismo , Radioinmunoensayo , Células del Estroma/fisiología
6.
Int J Infect Dis ; 118: 256-263, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35306205

RESUMEN

BACKGROUND: We nested a seroprevalence survey within the TREATS (Tuberculosis Reduction through Expanded Antiretroviral Treatment and Screening) project. We aimed to measure the seroprevalence of SARS-CoV-2 infection and investigate associated risk factors in one community (population ∼27,000) with high prevalence of TB/HIV in Zambia. METHODS: The study design was cross-sectional. A random sample of 3592 individuals aged ≥15 years enrolled in the TREATS TB-prevalence survey were selected for antibody testing. Randomly selected blocks of residence were visited between October 2020 and March 2021. Antibodies against SARS-CoV-2 were detected using Abbott- ARCHITECT SARS-CoV-2 IgG assay. RESULTS: A total of 3035/3526 (86.1%) individuals had a blood sample taken. Antibody testing results were available for 2917/3035 (96.1%) participants. Overall, 401/2977 (13.5%) individuals tested positive for IgG antibodies. Seroprevalence was similar by sex (12.7% men vs 14.0% women) and was lowest in the youngest age group 15-19 years (9.7%) and similar in ages 20 years and older (∼15%). We found no evidence of an association between seroprevalence and HIV-status or TB. There was strong evidence (p <0.001) of variation by time of enrollment, with prevalence varying from 2.8% (95% CI 0.8-4.9) among those recruited in December 2020 to 33.7% (95% CI 27.7-39.7) among those recruited in mid-February 2021. CONCLUSION: Seroprevalence was 13.5% but there was substantial variation over time, with a sharp increase to approximately 35% toward the end of the second epidemic wave.


Asunto(s)
COVID-19 , Infecciones por VIH , Anticuerpos Antivirales , COVID-19/epidemiología , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Humanos , Inmunoglobulina G , Masculino , Factores de Riesgo , SARS-CoV-2 , Estudios Seroepidemiológicos , Zambia/epidemiología
7.
Eur J Ophthalmol ; : 11206721211060140, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34812090

RESUMEN

PURPOSE: To evaluate treatment options for candida keratitis and endopthalmitis after corneal transplantation. METHODS: Case reports and literature review. RESULTS: Two patients with keratitis due to Candida glabrata/parapsilosis after corneal transplantation were successfully treated with a combination of topical voriconazole, intracameral voriconazole and amphotericin B, and systemic treatment with flucytosine. CONCLUSIONS: Natamycine and voriconazole topically are preferred therapeutic options for the treatment of fungal keratitis. Systemic flucytosine is a useful alternative additive, particularly for countries where natamycine is not registered as a pharmaceutical agent.

8.
Med Mycol Case Rep ; 30: 39-42, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33145152

RESUMEN

Mucormycosis is a life-threatening invasive fungal infection, most commonly described in severely immunocompromised patients. It is characterized by rapid invasive growth of the fungus and often with fatal outcome. We report a case of a renal transplant recipient diagnosed with a donor-derived invasive mucormycosis. In this patient, we used a step-wise approach of withdrawal of immunosuppressants, antifungal induction therapy, extensive surgical debridement of all (potentially) infected tissue, abdominal irrigation of liposomal amphotericin B and interferon gamma. Due to rapid diagnosis and intensive therapy the patient survived.

9.
Int J Tuberc Lung Dis ; 13(4): 460-5, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19335951

RESUMEN

SETTING: National TB Reference Laboratory, Zambia. OBJECTIVE: To compare four TB culture systems when used in a resource-limited setting. DESIGN: Comparison of four culture systems: automated Mycobacterium Growth Indicator Tube (AMGIT) 960, manual MGIT (MMGIT) and two Löwenstein-Jensen (LJ) culture media-commercial (CLJ) and homemade (HLJ). RESULTS: A total of 1916 sputum specimens were received, of which 261 (13.6%) were positive on microscopy. Mycobacterium tuberculosis complex (MTC) was isolated on at least one of the media in 410 (21.4%) specimens: MMGIT recovered 336 (17.5%) MTC, AMGIT 329 (17.2%), CLJ 192 (10.0%) and HLJ 184 (9.6%). The median time to detection for smear-negative specimens was 14 days for AMGIT, 16 days for MMGIT and 34 days for both LJ. Isolation of non-tuberculous mycobacteria (NTM) was more frequent in both MGIT systems (3.5%) than in CLJ (0.9%) and HLJ (0.8%). Contamination rates were high: 29.6% on AMGIT, 23.8% on MMGIT, 14.9% on CLJ and 12.5% on HLJ. CONCLUSION: Despite high contamination rates, either MGIT system considerably improved both the yield and the time to detection of MTC compared to LJ media. Investments in infrastructure and training are needed if culture is to be scaled up in low-income settings such as this.


Asunto(s)
Técnicas Bacteriológicas , Medios de Cultivo , Mycobacterium tuberculosis/aislamiento & purificación , Técnicas Bacteriológicas/economía , Humanos , Control de Calidad , Esputo/microbiología , Zambia
10.
Int J Food Sci Nutr ; 60 Suppl 6: 1-13, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19306224

RESUMEN

The present work aimed to evaluate the effectiveness of whole grain consumption in preventing colorectal cancer. A systematic review with meta-analysis of 11 cohort studies was carried out. The age group of the population studied (1,719,590 participants) was between 25 and 76 years of age. The review evaluated the relative risks with the Cox proportional hazard model. The period of study varied from 6 to 16 years, where 7,745 persons developed colorectal cancer during the follow-up period. In the multivariate analysis, the highest quintile relative risk was 0.94 (95% confidence interval, 0.85-1.03), whereas that for the lowest quintile was 0.96 (95% confidence interval, 0.88-1.04). The location of tumors was also evaluated, with tumors in the colon demonstrating a relative risk of 0.93 (95% confidence interval, 0.83-1.02) and tumors in the recto a relative risk equal to 0.89 (95% confidence interval, 0.79-1.00). In this multivariate analysis, consumption of whole grains was inversely associated with the risk of developing colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/prevención & control , Fibras de la Dieta/uso terapéutico , Grano Comestible/química , Medicina Basada en la Evidencia , Estudios de Cohortes , Neoplasias Colorrectales/epidemiología , Manipulación de Alimentos , Humanos , Riesgo
11.
Eur J Haematol ; 80(4): 303-9, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18182082

RESUMEN

PURPOSE: In this single-center analysis, we assessed whether lower thalidomide doses are feasible and result in favourable treatment response in multiple myeloma (MM) patients. RESULTS: Between May 2001 and October 2006, 38 consecutive MM patients received thalidomide. Their median age was 62.4 yr, all had stage II/III MM and 31.6% had deletion 13q14 (del13q14). Prior to thalidomide, patients had received a median of two treatment lines. The median thalidomide dose was 100 mg/d (range 50-800) and the median treatment duration was 34 wk. The median cumulative thalidomide dose was 24 g. Sixteen patients received thalidomide as a single agent and 22 in combination (+dexamethasone n = 18; others n = 4). The median time-to-treatment failure (TTF) after thalidomide initiation was 30.4 wk. Analysis of prognostic factors showed a significantly prolonged TTF without del13q14 (38.1 vs. 8.9 wk with del13q14; P = 0.006). Our analysis of TTF between thalidomide given alone vs. in combinations showed a better TTF for the combination (23.6 vs. 30.6 wk), albeit not reaching significance (P = 0.20). Other parameters, such as age, stage, and prior SCT showed no difference in TTF. Peripheral polyneuropathy (PNP) frequencies were increased with longer (>28 wk) and increased cumulative thalidomide doses (>40 g), which emphasizes (a) the need to carefully escalate thalidomide from 50 to 200 mg/d, thereby reducing side effects and increasing patient compliance, and (b) that PNP occurs more frequently with longer and higher thalidomide doses. CONCLUSION: The strategy to lower thalidomide doses seems a feasible and attractive approach in MM patients, this being currently tested in prospective randomized trials.


Asunto(s)
Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Talidomida/efectos adversos , Talidomida/uso terapéutico , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/clasificación , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento
12.
Vasa ; 37(4): 299-310, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19003739

RESUMEN

Due to increased long-distance travelling, travel-related thrombosis and its prevention are frequently discussed between patients and their doctors. There is now well accepted evidence that thromboembolic events can occur during or after long journeys, but despite a plethora of studies on the subject, still very little is known about the height of the absolute risk, the underlying triggering factors and, especially, about the efficacy of specific prophylactic methods. Therefore the recommendations for the prevention of travel-related thrombosis, developed and published by experts in this field, are necessarily based on the risk assessment of the individual traveller and the methods of prevention supported by the experience in medical patients.


Asunto(s)
Embolia Pulmonar , Viaje , Tromboembolia Venosa , Trombosis de la Vena , Medicina Basada en la Evidencia , Humanos , Guías de Práctica Clínica como Asunto , Embolia Pulmonar/etiología , Embolia Pulmonar/prevención & control , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control , Trombosis de la Vena/etiología , Trombosis de la Vena/prevención & control
13.
Curr Biol ; 10(13): 785-8, 2000 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-10898980

RESUMEN

BLyS (also called TALL-1, THANK, or BAFF) [1] [2] [3] [4] is a member of the tumor necrosis factor (TNF) gene family that stimulates proliferation and immunoglobulin production by B cells. BLyS interacts with the TNF receptor (TNFR) homologue TACI (transmembrane activator and CAML-interactor) [5], and treatment of mice with a TACI-Fc fusion protein abolishes germinal center formation after antigenic challenge [6]. Here we report a novel interaction between BLyS and another TNFR homologue, BCMA (B cell maturation antigen) [7] [8]. Further, the TNF homologue APRIL [9], a close relative of BLyS, also bound to BCMA and TACI. BLyS or APRIL activated nuclear factor-kappaB (NF-kappaB) through TACI and BCMA, and each ligand stimulated immunoglobulin M (IgM) production by peripheral blood B cells. These results define a dual ligand-receptor system that may play an important role in humoral immunity.


Asunto(s)
Proteínas de la Membrana/metabolismo , Receptores del Factor de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Secuencia de Aminoácidos , Animales , Factor Activador de Células B , Antígeno de Maduración de Linfocitos B , Células CHO , Línea Celular , Cricetinae , Humanos , Inmunoglobulina M/metabolismo , Leucocitos/citología , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , FN-kappa B/metabolismo , Unión Proteica , Receptores del Factor de Necrosis Tumoral/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Homología de Secuencia de Aminoácido , Proteína Activadora Transmembrana y Interactiva del CAML , Miembro 13 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/genética
14.
Int J Biometeorol ; 52(2): 127-37, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17587065

RESUMEN

This study assesses the impact of a changing climate on fish fauna by comparing the past mean state of fish assemblage to a possible future mean state. It is based on (1) local scale observations along an Inner-Alpine river called Mur, (2) an IPCC emission scenario (IS92a), implemented by atmosphere-ocean global circulation model (AOGCM) ECHAM4/OPYC3, and (3) a model-chain that links climate research to hydrobiology. The Mur River is still in a near-natural condition and water temperature in summer is the most important aquatic ecological constraint for fish distribution. The methodological strategy is (1) to use downscaled air temperature and precipitation scenarios for the first half of the twenty-first century, (2) to establish a model that simulates water temperature by means of air temperature and flow rate in order to generate water temperature scenarios, and (3) to evaluate the impact on fish communities using an ecological model that is driven by water temperature. This methodology links the response of fish fauna to an IPCC emission scenario and is to our knowledge an unprecedented approach. The downscaled IS92a scenarios show increased mean air temperatures during the whole year and increased precipitation totals during summer, but reduced totals for the rest of the annual cycle. These changes result in scenarios of increased water temperatures, an altered annual cycle of flow rate, and, in turn, a 70 m displacement in elevation of fish communities towards the river's head. This would enhance stress on species that rely on low water temperatures and coerce cyprinid species into advancing against retreating salmonids. Hyporhithral river sectors would turn into epipotamal sectors. Grayling (Thymallus thymallus) and Danube salmon (Hucho hucho), presently characteristic for the Mur River, would be superceded by other species. Native brown trout (Salmo trutta), already now under pressure of competition, may be at risk of losing its habitat in favour of invaders like the exotic rainbow trout (Oncorhynchus mykiss), which are better adapted to higher water temperatures. Projected changes in fish communities suggest an adverse influence on salmonid sport fishing and a loss in its high economic value.


Asunto(s)
Aclimatación/fisiología , Conducta Animal/fisiología , Clima , Ecosistema , Ambiente , Peces/fisiología , Modelos Biológicos , Ríos , Animales , Simulación por Computador , Alemania
15.
Bone Marrow Transplant ; 38(6): 437-44, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16892071

RESUMEN

Combinations of HLA and killer immunoglobulin-like receptors (KIR) may affect outcome in T-cell depleted haematopoietic stem cell transplantation (HSCT). The KIR gene family includes inhibitory (KIR2DL and 3DL) and activating receptors (KIR2DS). Ligands are HLA-C (KIR2D) and HLA-Bw4 (KIR3DL1) for inhibitory KIR and are still unknown for activating KIR. The impact of activating KIR genotypes from donor and recipient is poorly documented in HSCT outcome. Here, HLA and KIR genotypes were determined in 131 pairs from non-T-cell depleted HLA-identical sibling HSCT. No effect of 'missing KIR ligand' was detected on acute graft-versus-host disease (GVHD), relapse, survival or infections even in myeloid malignancies. However, additional activating KIR genes in the donor compared to the recipient's genotype or an identity between donor and recipient activating KIR genotypes was associated with a lower transplant-related mortality (TRM) (P=0.005) and in a multivariate analysis with a better survival (P=0.02, HR=0.28; P=0.013, HR=0.29) and a lower incidence of cytomegalovirus (CMV) reactivation (P=0.009, HR=0.36). These data highlight the impact of donor-activating KIR genes on TRM, overall survival and CMV reactivation in HLA-identical sibling HSCT.


Asunto(s)
Donantes de Sangre , Trasplante de Médula Ósea , Infecciones por Citomegalovirus/genética , Antígenos HLA , Neoplasias/genética , Receptores Inmunológicos/genética , Linfocitos T , Activación Viral/genética , Adolescente , Adulto , Trasplante de Médula Ósea/efectos adversos , Trasplante de Médula Ósea/mortalidad , Niño , Preescolar , Citomegalovirus/genética , Infecciones por Citomegalovirus/etiología , Infecciones por Citomegalovirus/mortalidad , Supervivencia sin Enfermedad , Femenino , Genotipo , Humanos , Depleción Linfocítica , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/mortalidad , Neoplasias/terapia , Neoplasias/virología , Receptores KIR , Receptores KIR3DL1 , Estudios Retrospectivos , Hermanos , Tasa de Supervivencia , Trasplante Homólogo
16.
Clin Microbiol Infect ; 12(8): 769-75, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16842572

RESUMEN

A previous limited study demonstrated that Mycobacterium tuberculosis isolates with a mutation at amino-acid position 315 of katG (Delta315) exhibited high-level resistance to isoniazid and were more frequently resistant to streptomycin. In the present study, isoniazid-resistant M. tuberculosis isolates from 8,332 patients in The Netherlands (1993-2002) were screened for the Delta315 mutation. Isoniazid resistance was found in 592 (7%) isolates, of which 323 (55%) carried Delta315. IS6110 restriction fragment length polymorphism analysis showed that Delta315 isolates occurred in clusters, suggesting recent transmission, at the same frequency as isoniazid-susceptible isolates. In contrast, other isoniazid-resistant isolates clustered significantly less frequently. Delta315 isolates were high-level isoniazid-resistant, streptomycin-resistant and multidrug-resistant significantly more often, and may have a greater impact on public health, than other isoniazid-resistant isolates.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/genética , Catalasa/genética , Isoniazida/farmacología , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Adolescente , Adulto , Anciano , Farmacorresistencia Bacteriana Múltiple , Humanos , Persona de Mediana Edad , Mycobacterium tuberculosis/genética , Salud Pública
17.
J Natl Cancer Inst ; 92(15): 1252-9, 2000 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-10922410

RESUMEN

BACKGROUND: Studies by comparative genomic hybridization (CGH) have shown that chromosomal region 17q23 is amplified in up to 20% of primary breast cancers. We used microarray analyses to measure the expression levels of genes in this region and to explore their prognostic importance. METHODS: A microarray that contained 4209 complementary DNA (cDNA) clones was used to identify genes that are overexpressed in the MCF-7 breast cancer cell line as compared with normal mammary tissue. Fluorescence in situ hybridization was used to analyze the copy number of one overexpressed gene, ribosomal protein S6 kinase (S6K), and to localize it to the 17q23 region. Northern and western blot analyses were used to measure S6K gene and protein expression, and an enzymatic assay was used to measure S6K activity. Tumor tissue microarray analysis was used to study amplification of S6K and the HER-2 oncogene, another 17q-linked gene, and the relationship between amplification and prognosis was analyzed. The Kaplan-Meier method was used for data analysis, and the log-rank test was used for statistical analysis. All P values are two-sided. RESULTS: S6K was amplified and highly overexpressed in MCF-7 cells relative to normal mammary epithelium, and protein expression and enzyme activity were increased. S6K was amplified in 59 (8.8%) of 668 primary breast tumors, and a statistically significant association between amplification and poor prognosis (P =.0021) was observed. Amplification of both S6K and HER-2 implied particularly poor survival (P =.0001). CONCLUSIONS: The combination of CGH information with cDNA and tissue microarray analyses can be used to identify amplified and overexpressed genes and to evaluate the clinical implications of such genes and genomic rearrangements. S6K is likely to be one of the genes at 17q23 that is amplified during oncogenesis and may adversely affect the prognosis of patients with this amplification.


Asunto(s)
Neoplasias de la Mama/enzimología , Neoplasias de la Mama/genética , Cromosomas Humanos Par 17/genética , ADN de Neoplasias/análisis , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Quinasas S6 Ribosómicas/metabolismo , Northern Blotting , Western Blotting , Mama/enzimología , ADN Complementario , Activación Enzimática , Femenino , Regulación Neoplásica de la Expresión Génica , Genes erbB-2/genética , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Pronóstico , Proteínas Quinasas S6 Ribosómicas/genética , Análisis de Supervivencia , Células Tumorales Cultivadas , Regulación hacia Arriba
18.
Biochim Biophys Acta ; 1030(1): 176-81, 1990 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-2265188

RESUMEN

Regeneration of bacteriorhodopsin from bacterioopsin and all-trans-retinal was studied in a mixed micelle system consisting of dodecyl sulfate, CHAPS and a water-soluble phospholipid dihexanoylphosphatidylcholine (hex2-PhosChol). Regeneration to approximately 40,000 M-1.cm-1 extinction at 550 nm (epsilon 550) was obtained with either 2.3 mM or 6.5 mM CHAPS along with 6.9 mM dodecyl sulfate and 4.5 mM hex2-PhosChol in 0.16 M NaCl and 40 mM phosphate (pH 6.0). Without CHAPS, the regeneration in 4.5 mM Hex2-PhosChol gave epsilon 555 = 27,800; without PhosChol, the 1:3 CHAPS/dodecyl sulfate mixture gave epsilon 550 approximately 20,000; and without PhosChol the nearly equimolar CHAPS/dodecyl sulfate mixture gave epsilon 550 approximately 10,000. The composition of the mixed micelles was estimated from fluorescence spectroscopy using pyrene butyryl hydrazine. The molecular weight was estimated by molecular seive chromatography to be 87,100 for 2.3 mM CHAPS, 6.9 mM dodecyl sulfate and 0.67 mM hex2-PhosChol; and 83,200 for 7.0 mM CHAPS, 6.9 mM dodecyl sulfate, and 1.1 mM hex2-PhosChol. These results are consistent with the idea that at low concentrations of CHAPS and dodecyl sulfate, CHAPS organizes the dodecyl sulfate into disk shaped bilayer micelles that are favorable for bacterioopsin refolding. However, a high concentration of either detergent inhibits regeneration. Added hex2-PhosChol can overcome the inhibitory effects of high concentrations of either CHAPS or dodecyl sulfate.


Asunto(s)
Bacteriorodopsinas/metabolismo , Halobacterium/análisis , Micelas , Ácidos Cólicos/administración & dosificación , Ácidos Cólicos/farmacología , Cromatografía en Gel , Colorantes Fluorescentes , Hidrazinas , Peso Molecular , Fosfatidilcolinas , Conformación Proteica , Dodecil Sulfato de Sodio/administración & dosificación , Dodecil Sulfato de Sodio/farmacología , Espectrometría de Fluorescencia
19.
Ann Hematol ; 84 Suppl 1: 25-31, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16292666

RESUMEN

Intravenous low-dose 5-aza-2'-deoxycytidine (decitabine) in patients with advanced myelodysplastic syndrome (MDS) yields an approximately 50% overall response rate, including 20-25% complete remission. Decitabine-treated MDS patients can be managed as outpatients after completion of a 3-day infusion schedule. In-hospital nights (IHNs), overall survival (OS), and remaining life spent in hospital were evaluated and compared to a matched control group receiving different standard treatments. Between July 1992 and September 2001, 99 high-risk MDS patients, median age 70 years (range 49-86), were treated with low-dose decitabine. Durations of all hospitalizations were recorded. For matched-pair analysis, 44 decitabine-treated patients were matched to 44 MDS patients according to International Prognostic Scoring System classification, period of diagnosis, age, French-American-British classification, and gender. Median number of IHN across all patients was 56 and survival was 481 days, resulting in 84% of remaining life spent at home. In the matched-pair analysis, the median number of IHN was 57 in the decitabine group vs. 50 in the control group. Median survival was 400 vs. 371 days for the decitabine and control groups, respectively. Median number of remaining life spent at home was identical (83% for both groups). Matched patients who received only best supportive care (n=12) had a shorter median survival than the decitabine patients (234 vs. 400 days), and the proportion of remaining life spent at home was slightly greater (82 vs. 77%). Interestingly, matched patients with induction therapy showed comparable IHN, OS, and remaining life spent at home. In conclusion, high-risk MDS patients treated with low-dose decitabine have better survival, and spend comparable time in hospital than patients treated with supportive treatment.


Asunto(s)
Atención Ambulatoria/métodos , Antineoplásicos/administración & dosificación , Azacitidina/análogos & derivados , Síndromes Mielodisplásicos/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Azacitidina/administración & dosificación , Estudios de Casos y Controles , Metilasas de Modificación del ADN/antagonistas & inhibidores , Decitabina , Femenino , Humanos , Tiempo de Internación , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Síndromes Mielodisplásicos/rehabilitación , Calidad de Vida , Estudios Retrospectivos , Análisis de Supervivencia
20.
Parasite ; 12(3): 271-5, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16218216

RESUMEN

Leishmaniosis caused by Leishmania infantum is an endemic zoonosis present in the Mediterranean area. Canidae (dog and fox) constitute the main reservoir hosts for the parasite, whilst wild rodents or the cat can be carriers of the protozoan and are considered as secondary potential reservoirs. This paper describes a case of disseminated feline leishmaniosis with cutaneous (ulcerative), visceral (spleen and lymph nodes) and blood involvement in a FIV-FelV positive cat. The microscopic identification of the Leishmania infection was initially made on a skin biopsy of the temporal area, where a squamous cell carcinoma was diagnosed. The diagnosis of the disease was achieved by several serological techniques (ELISA, IFAT and Western-blot). The strain was obtained by blood culture, characterized by electrophoresis of isoenzymes and identified as Leishmania infantum zymodeme MON-1. Since the infection due to L. infantum is a zoonosis, the potential feline reservoir should be more investigated. Serological analysis by Western blot on domestic cats provides a useful tool. In veterinary practice, feline leishmaniosis should be systematically included in the differential diagnosis when compatible cutaneous lesions are present, especially in the endemic areas of canine leishmaniosis.


Asunto(s)
Carcinoma de Células Escamosas/veterinaria , Enfermedades de los Gatos/parasitología , Leishmania infantum , Leishmaniasis Visceral/veterinaria , Leucemia Felina/complicaciones , Animales , Carcinoma de Células Escamosas/complicaciones , Gatos , Síndrome de Inmunodeficiencia Adquirida del Felino/complicaciones , Femenino , Leishmaniasis Visceral/complicaciones , Macrófagos/parasitología , Macrófagos/patología
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