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1.
Mol Biol Evol ; 39(1)2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34662416

RESUMEN

The soil bacterium Burkholderia pseudomallei is the causative agent of melioidosis and a significant cause of human morbidity and mortality in many tropical and subtropical countries. The species notoriously survives harsh environmental conditions but the genetic architecture for these adaptations remains unclear. Here we employed a powerful combination of genome-wide epistasis and co-selection studies (2,011 genomes), condition-wide transcriptome analyses (82 diverse conditions), and a gene knockout assay to uncover signals of "co-selection"-that is a combination of genetic markers that have been repeatedly selected together through B. pseudomallei evolution. These enabled us to identify 13,061 mutation pairs under co-selection in distinct genes and noncoding RNA. Genes under co-selection displayed marked expression correlation when B. pseudomallei was subjected to physical stress conditions, highlighting the conditions as one of the major evolutionary driving forces for this bacterium. We identified a putative adhesin (BPSL1661) as a hub of co-selection signals, experimentally confirmed a BPSL1661 role under nutrient deprivation, and explored the functional basis of co-selection gene network surrounding BPSL1661 in facilitating the bacterial survival under nutrient depletion. Our findings suggest that nutrient-limited conditions have been the common selection pressure acting on this species, and allelic variation of BPSL1661 may have promoted B. pseudomallei survival during harsh environmental conditions by facilitating bacterial adherence to different surfaces, cells, or living hosts.


Asunto(s)
Evolución Biológica , Burkholderia pseudomallei , Adhesinas Bacterianas , Alelos , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/fisiología , Selección Genética , Estrés Fisiológico
2.
BMC Med ; 21(1): 320, 2023 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-37620809

RESUMEN

BACKGROUND: Severe malaria in pregnancy causes maternal mortality, morbidity, and adverse foetal outcomes. The factors contributing to adverse maternal and foetal outcomes are not well defined. We aimed to identify the factors predicting higher maternal mortality and to describe the foetal mortality and morbidity associated with severe falciparum malaria in pregnancy. METHODS: A retrospective cohort study was conducted of severe falciparum malaria in pregnancy, as defined by the World Health Organization severe malaria criteria. The patients were managed prospectively by the Shoklo Malaria Research Unit (SMRU) on the Thailand-Myanmar border or were included in hospital-based clinical trials in six Southeast Asian countries. Fixed-effects multivariable penalised logistic regression was used for analysing maternal mortality. RESULTS: We included 213 (123 SMRU and 90 hospital-based) episodes of severe falciparum malaria in pregnancy managed between 1980 and 2020. The mean maternal age was 25.7 (SD 6.8) years, and the mean gestational age was 25.6 (SD 8.9) weeks. The overall maternal mortality was 12.2% (26/213). Coma (adjusted odds ratio [aOR], 7.18, 95% CI 2.01-25.57, p = 0.0002), hypotension (aOR 11.21, 95%CI 1.27-98.92, p = 0.03) and respiratory failure (aOR 4.98, 95%CI 1.13-22.01, p = 0.03) were associated with maternal mortality. Pregnant women with one or more of these three criteria had a mortality of 29.1% (25/86) (95%CI 19.5 to 38.7%) whereas there were no deaths in 88 pregnant women with hyperparasitaemia (> 10% parasitised erythrocytes) only or severe anaemia (haematocrit < 20%) only. In the SMRU prospective cohort, in which the pregnant women were followed up until delivery, the risks of foetal loss (23.3% by Kaplan-Meier estimator, 25/117) and small-for-gestational-age (38.3%, 23/60) after severe malaria were high. Maternal death, foetal loss and preterm birth occurred commonly within a week of diagnosis of severe malaria. CONCLUSIONS: Vital organ dysfunction in pregnant women with severe malaria was associated with a very high maternal and foetal mortality whereas severe anaemia or hyperparasitaemia alone were not associated with poor prognosis, which may explain the variation of reported mortality from severe malaria in pregnancy. Access to antenatal care must be promoted to reduce barriers to early diagnosis and treatment of both malaria and anaemia.


Asunto(s)
Nacimiento Prematuro , Recién Nacido , Embarazo , Humanos , Femenino , Adulto , Lactante , Estudios Prospectivos , Estudios Retrospectivos , Mianmar , Feto
3.
Artículo en Inglés | MEDLINE | ID: mdl-33526485

RESUMEN

When severe malaria is suspected in children, the WHO recommends pretreatment with a single rectal dose of artesunate before referral to an appropriate facility. This was an individually randomized, open-label, 2-arm, crossover clinical trial in 82 Congolese children with severe falciparum malaria to characterize the pharmacokinetics of rectal artesunate. At admission, children received a single dose of rectal artesunate (10 mg/kg of body weight) followed 12 h later by intravenous artesunate (2.4 mg/kg) or the reverse order. All children also received standard doses of intravenous quinine. Artesunate and dihydroartemisinin were measured at 11 fixed intervals, following 0- and 12-h drug administrations. Clinical, laboratory, and parasitological parameters were measured. After rectal artesunate, artesunate and dihydroartemisinin showed large interindividual variability (peak concentrations of dihydroartemisinin ranged from 5.63 to 8,090 nM). The majority of patients, however, reached previously suggested in vivo IC50 and IC90 values (98.7% and 92.5%, respectively) of combined concentrations of artesunate and dihydroartemisinin between 15 and 30 min after drug administration. The median (interquartile range [IQR]) time above IC50 and IC90 was 5.68 h (2.90 to 6.08) and 2.74 h (1.52 to 3.75), respectively. The absolute rectal bioavailability (IQR) was 25.6% (11.7 to 54.5) for artesunate and 19.8% (10.3 to 35.3) for dihydroartemisinin. The initial 12-h parasite reduction ratio was comparable between rectal and intravenous artesunate: median (IQR), 84.3% (50.0 to 95.4) versus 69.2% (45.7 to 93.6), respectively (P = 0.49). Despite large interindividual variability, rectal artesunate can initiate and sustain rapid parasiticidal activity in most children with severe falciparum malaria while they are transferred to a facility where parenteral artesunate is available. (This study has been registered at ClinicalTrials.gov under identifier NCT02492178.).


Asunto(s)
Antimaláricos , Malaria Falciparum , Malaria , África , Antimaláricos/uso terapéutico , Artesunato/uso terapéutico , Niño , Humanos , Malaria/tratamiento farmacológico , Malaria Falciparum/tratamiento farmacológico , Quinina
4.
BMC Infect Dis ; 15: 98, 2015 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-25887604

RESUMEN

BACKGROUND: Tuberculosis (TB) is an important cause of morbidity and mortality worldwide. Toll-like-receptors (TLRs) are important for the recognition of the causative agent Mycobacterium tuberculosis. Negative regulation of TLRs is necessary to control deleterious inflammatory damage, but could provide a means of immune evasion by M. tuberculosis as well. METHODS: To obtain insight in the extent of expression of inhibitory regulators of immunity in patients with active TB, peripheral-blood-mononuclear-cells (PBMCs) and plasma were obtained from 54 TB patients and 29 healthy blood donors from Chittagong, Bangladesh. Bilateral alveolar macrophages were obtained from an infected versus a contralateral normal lung segment of 9 patients. Statistical analyses were performed using Mann-Whitney U and Wilcoxon matched pairs testing. Correlations were calculated using the Spearman rho test. RESULTS: PBMCs harvested from TB patients demonstrated increased mRNA expression of IL-1-receptor-associated-kinase-M, suppressor-of-cytokine-signalling-3 and Toll-interacting-protein. Flow cytometry revealed enhanced expression of IL-1-receptor-like-1 (ST2) on lymphocytes. Plasma soluble ST2 was elevated in patients with TB and correlated with established TB biomarkers, most strongly with soluble interleukin-2 receptor subunit α and interleukin-8. Alveolar macrophage mRNA expression of negative TLR regulators did not differ between the infected and contralateral lung side. CONCLUSION: These results show enhanced expression of distinct negative regulators of innate immunity in PBMCs of patients with TB and identify plasma soluble ST2 as a potential novel biomarker for TB disease activity.


Asunto(s)
Inmunidad Innata/inmunología , Tuberculosis Pulmonar/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bangladesh/epidemiología , Femenino , Citometría de Flujo , Humanos , Interleucina-8/inmunología , Leucocitos Mononucleares/inmunología , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/inmunología , Receptores Toll-Like/inmunología , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/epidemiología , Adulto Joven
5.
Am J Trop Med Hyg ; 104(3): 1022-1033, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33432906

RESUMEN

Epidemiology, ventilator management, and outcome in patients receiving invasive ventilation in intensive care units (ICUs) in middle-income countries are largely unknown. PRactice of VENTilation in Middle-income Countries is an international multicenter 4-week observational study of invasively ventilated adult patients in 54 ICUs from 10 Asian countries conducted in 2017/18. Study outcomes included major ventilator settings (including tidal volume [V T ] and positive end-expiratory pressure [PEEP]); the proportion of patients at risk for acute respiratory distress syndrome (ARDS), according to the lung injury prediction score (LIPS), or with ARDS; the incidence of pulmonary complications; and ICU mortality. In 1,315 patients included, median V T was similar in patients with LIPS < 4 and patients with LIPS ≥ 4, but lower in patients with ARDS (7.90 [6.8-8.9], 8.0 [6.8-9.2], and 7.0 [5.8-8.4] mL/kg Predicted body weight; P = 0.0001). Median PEEP was similar in patients with LIPS < 4 and LIPS ≥ 4, but higher in patients with ARDS (five [5-7], five [5-8], and 10 [5-12] cmH2O; P < 0.0001). The proportions of patients with LIPS ≥ 4 or with ARDS were 68% (95% CI: 66-71) and 7% (95% CI: 6-8), respectively. Pulmonary complications increased stepwise from patients with LIPS < 4 to patients with LIPS ≥ 4 and patients with ARDS (19%, 21%, and 38% respectively; P = 0.0002), with a similar trend in ICU mortality (17%, 34%, and 45% respectively; P < 0.0001). The capacity of the LIPS to predict development of ARDS was poor (receiver operating characteristic [ROC] area under the curve [AUC] of 0.62, 95% CI: 0.54-0.70). In Asian middle-income countries, where two-thirds of ventilated patients are at risk for ARDS according to the LIPS and pulmonary complications are frequent, setting of V T is globally in line with current recommendations.


Asunto(s)
Países en Desarrollo/estadística & datos numéricos , Monitoreo Epidemiológico , Unidades de Cuidados Intensivos/estadística & datos numéricos , Respiración Artificial/métodos , Respiración Artificial/estadística & datos numéricos , Síndrome de Dificultad Respiratoria/terapia , Adulto , Anciano , Asia/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Síndrome de Dificultad Respiratoria/epidemiología , Resultado del Tratamiento
6.
J Phys Chem A ; 114(43): 11825-32, 2010 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-20923209

RESUMEN

This work presents thermochemical data for possible gas phase intermediate species in an industrial rutile chlorinator. An algorithm developed for previous work is employed to ensure that all possible species are considered, reducing the number of important species neglected. Thermochemical data and enthalpies of formation are calculated for 22 new species using density functional theory, post Hartree-Fock coupled cluster calculations, and statistical mechanics. Equilibrium calculations are performed to identify whether any Ti/C intermediates are likely to be important to the high temperature industrial process. These new species are not present at high concentration in the exit stream. It is therefore likely that the two chemical processes do not interact. Rather, the Cl2 rapidly reacts with the solid TiO2 to form TiCl4 and O2. The latter then reacts with the solid C to form CO and CO2 and provide the heat. Data for all the new species is provided as Supporting Information. Finally, a new methodology for data collaboration is investigated in which the data is made openly accessible using the resource description framework. Example scripts are provided to demonstrate how to query and retrieve the data automatically.


Asunto(s)
Cloruros/química , Teoría Cuántica , Termodinámica , Algoritmos , Gases/química , Oxígeno/química , Titanio/química
7.
Malar J ; 8: 152, 2009 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-19589177

RESUMEN

BACKGROUND: In Vietnam the blackwater fever syndrome (BWF) has been associated with malaria infection, quinine ingestion and G6PD deficiency. The G6PD variants within the Vietnamese Kinh contributing to the disease risk in this population, and more generally to haemoglobinuria, are currently unknown. METHOD: Eighty-two haemoglobinuria patients and 524 healthy controls were screened for G6PD deficiency using either the methylene blue reduction test, the G-6-PDH kit or the micro-methaemoglobin reduction test. The G6PD gene variants were screened using SSCP combined with DNA sequencing in 82 patients with haemoglobinuria, and in 59 healthy controls found to be G6PD deficient. RESULTS: This study confirmed that G6PD deficiency is strongly associated with haemoglobinuria (OR = 15, 95% CI [7.7 to 28.9], P < 0.0001). Six G6PD variants were identified in the Vietnamese population, of which two are novel (Vietnam1 [Glu3Lys] and Vietnam2 [Phe66Cys]). G6PD Viangchan [Val291Met], common throughout south-east Asia, accounted for 77% of the variants detected and was significantly associated with haemoglobinuria within G6PD-deficient ethnic Kinh Vietnamese (OR = 5.8 95% CI [114-55.4], P = 0.022). CONCLUSION: The primary frequency of several G6PD mutations, including novel mutations, in the Vietnamese Kinh population are reported and the contribution of G6PD mutations to the development of haemoglobinuria are investigated.


Asunto(s)
Pueblo Asiatico/genética , Deficiencia de Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/genética , Hemoglobinuria/genética , Mutación/genética , Asia Sudoriental , Estudios de Casos y Controles , Femenino , Variación Genética , Glucosafosfato Deshidrogenasa/metabolismo , Deficiencia de Glucosafosfato Deshidrogenasa/epidemiología , Deficiencia de Glucosafosfato Deshidrogenasa/etnología , Hemoglobinuria/epidemiología , Humanos , Masculino , Azul de Metileno , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Síndrome , Vietnam/epidemiología
8.
Cancer Epidemiol Biomarkers Prev ; 17(5): 1074-81, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18483328

RESUMEN

Breast density is a well-known breast cancer risk factor. Most current methods of measuring breast density are area based and subjective. Standard mammogram form (SMF) is a computer program using a volumetric approach to estimate the percent density in the breast. The aim of this study is to evaluate the current implementation of SMF as a predictor of breast cancer risk by comparing it with other widely used density measurement methods. The case-control study comprised 634 cancers with 1,880 age-matched controls combined from the Cambridge and Norwich Breast Screening Programs. Data collection involved assessing the films based both on Wolfe's parenchymal patterns and on visual estimation of percent density and then digitizing the films for computer analysis (interactive threshold technique and SMF). Logistic regression was used to produce odds ratios associated with increasing categories of breast density. Density measures from all four methods were strongly associated with breast cancer risk in the overall population. The stepwise rises in risk associated with increasing density as measured by the threshold method were 1.37 [95% confidence interval (95% CI), 1.03-1.82], 1.80 (95% CI, 1.36-2.37), and 2.45 (95% CI, 1.86-3.23). For each increasing quartile of SMF density measures, the risks were 1.11 (95% CI, 0.85-1.46), 1.31 (95% CI, 1.00-1.71), and 1.92 (95% CI, 1.47-2.51). After the model was adjusted for SMF results, the threshold readings maintained the same strong stepwise increase in density-risk relationship. On the contrary, once the model was adjusted for threshold readings, SMF outcome was no longer related to cancer risk. The available implementation of SMF is not a better cancer risk predictor compared with the thresholding method.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mamografía/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Programas Informáticos
9.
Trans R Soc Trop Med Hyg ; 101(7): 633-4, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17434195

RESUMEN

In the SEAQUAMAT trial, parenteral artesunate was shown to be associated with a considerably lower mortality than quinine, and is now the recommended treatment for severe malaria in low-transmission areas and in the second and third trimesters of pregnancy. A trial is underway to establish its role in African children. The development of artesunate suppositories may provide the means to treat patients with severe disease in remote rural settings, potentially buying the time needed to reach a health care facility. The increasing availability of basic intensive care facilities in developing countries also has the potential to further reduce mortality.


Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Sesquiterpenos/uso terapéutico , Adulto , África/epidemiología , Artesunato , Asia/epidemiología , Niño , Preescolar , Femenino , Humanos , Malaria Falciparum/mortalidad , Embarazo , Quinina/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Supositorios
10.
Lancet ; 366(9487): 717-25, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16125588

RESUMEN

BACKGROUND: In the treatment of severe malaria, intravenous artesunate is more rapidly acting than intravenous quinine in terms of parasite clearance, is safer, and is simpler to administer, but whether it can reduce mortality is uncertain. METHODS: We did an open-label randomised controlled trial in patients admitted to hospital with severe falciparum malaria in Bangladesh, India, Indonesia, and Myanmar. We assigned individuals intravenous artesunate 2.4 mg/kg bodyweight given as a bolus (n=730) at 0, 12, and 24 h, and then daily, or intravenous quinine (20 mg salt per kg loading dose infused over 4 h then 10 mg/kg infused over 2-8 h three times a day; n=731). Oral medication was substituted when possible to complete treatment. Our primary endpoint was death from severe malaria, and analysis was by intention to treat. FINDINGS: We assessed all patients randomised for the primary endpoint. Mortality in artesunate recipients was 15% (107 of 730) compared with 22% (164 of 731) in quinine recipients; an absolute reduction of 34.7% (95% CI 18.5-47.6%; p=0.0002). Treatment with artesunate was well tolerated, whereas quinine was associated with hypoglycaemia (relative risk 3.2, 1.3-7.8; p=0.009). INTERPRETATION: Artesunate should become the treatment of choice for severe falciparum malaria in adults.


Asunto(s)
Antimaláricos/uso terapéutico , Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Quinina/uso terapéutico , Sesquiterpenos/uso terapéutico , Adolescente , Artesunato , Preescolar , Femenino , Humanos , Malaria Falciparum/mortalidad , Masculino , Tasa de Supervivencia
11.
Malar J ; 5: 71, 2006 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-16907979

RESUMEN

BACKGROUND: Plasmodium vivax malaria accounts for approximately 60% of malaria cases in Kolkata, India. There has been limited information on the genotypic polymorphism of P. vivax in this malaria endemic area. Three highly polymorphic and single copy genes were selected for a study of genetic diversity in Kolkata strains. METHODS: Blood from 151 patients with P. vivax infection diagnosed in Kolkata between April 2003 and September 2004 was genotyped at three polymorphic loci: the P. vivax circumsporozoite protein (pvcs), the merozoite surface protein 1 (pvmsp1) and the merozoite surface protein 3-alpha (pvmsp3-alpha). RESULTS: Analysis of these three genetic markers revealed that P. vivax populations in Kolkata are highly diverse. A large number of distinguishable alleles were found from three genetic markers: 11 for pvcs, 35 for pvmsp1 and 37 for pvmsp3-alpha. These were, in general, randomly distributed amongst the isolates. Among the 151 isolates, 142 unique genotypes were detected the commonest genotype at a frequency of less than 2% (3/151). The overall rate of mixed genotype infections was 10.6%. CONCLUSION: These results indicate that the P. vivax parasite population is highly diverse in Kolkata, despite the low level of transmission. The genotyping protocols used in this study may be useful for differentiating re-infection from relapse and recrudescence in studies assessing of malarial drug efficacy in vivax malaria.


Asunto(s)
Antígenos de Protozoos/genética , Frecuencia de los Genes , Plasmodium vivax/genética , Polimorfismo Genético/genética , Animales , Marcadores Genéticos , Genotipo , Humanos , India , Proteína 1 de Superficie de Merozoito/genética , Filogenia , Plasmodium vivax/clasificación , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción
12.
Breast Cancer Res ; 7(2): R204-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15743501

RESUMEN

INTRODUCTION: About two-thirds of the excess familial risk associated with breast cancer is still unaccounted for and may be explained by multiple weakly predisposing alleles. A gene thought to be involved in low-level predisposition to the disease is ERBB2 (HER2). This gene is involved in cell division, differentiation, and apoptosis and is frequently amplified in breast tumours. Its amplification correlates with poor prognosis. Moreover, the coding polymorphism I655V has previously been associated with an increased risk of breast cancer. METHODS: We aimed to determine if common polymorphisms (frequency >or= 5%) in ERBB2 were associated with breast cancer risk in a white British population. Five single-nucleotide polymorphisms (SNPs) were selected for study: SNP 1 near the promoter, SNP 2 in intron 1, SNP 3 in intron 4, SNP 4 in exon 17 (I655V), and SNP 5 in exon 27 (A1170P). We tested their association with breast cancer in a large case-control study (n = 2192 cases and 2257 controls). RESULTS: There were no differences in genotype frequencies between cases and controls for any of the SNPs examined. To investigate the possibility that a common polymorphism not included in our study might be involved in breast cancer predisposition, we also constructed multilocus haplotypes. Our set of SNPs generated all existing (n = 6) common haplotypes and no differences were seen in haplotype frequencies between cases and controls (P = 0.44). CONCLUSIONS: In our population, common ERBB2 polymorphisms are not involved in predisposition to breast cancer.


Asunto(s)
Predisposición Genética a la Enfermedad , Receptor ErbB-2/genética , Población Blanca/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Inglaterra , Exones , Femenino , Genotipo , Haplotipos , Humanos , Intrones , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Receptor ErbB-2/fisiología , Factores de Riesgo
13.
Cancer Epidemiol Biomarkers Prev ; 14(1): 213-20, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15668497

RESUMEN

Cross-sectional studies investigating the relationship between phytoestrogens in diet, urine, or blood with plasma estradiol and sex hormone binding globulin (SHBG) have been inconclusive. We investigated the relationship among phytoestrogen exposure, polymorphisms in the ESR1, COMT, CYP19, and SHBG genes, and plasma estradiol and SHBG levels in 125 free-living postmenopausal women taking part in a cohort study (European Prospective Investigation of Cancer and Nutrition-Norfolk) using three different markers: dietary, urinary, and serum phytoestrogens. Phytoestrogen levels (daidzein, genistein, glycitein, O-desmethylangolensin, equol, enterodiol, and enterolactone) in spot urine and serum were analyzed by gas chromatography/mass spectrometry and liquid chromatography/tandem mass spectrometry, respectively. Plasma estradiol and SHBG were measured by immunoassays. Adjusting for age and body mass index, urinary daidzein, genistein, glycitein, and serum daidzein and glycitein were negatively correlated with plasma estradiol (R = -0.199 to -0.277, P <0.03), with particularly strong associations found in the 18 women with CC genotype for ESR1 PvuII polymorphism (R = -0.597 to -0.834, P < 0.03). The negative correlations observed between isoflavones and estradiol in women as a whole became no longer significant when we excluded women with ESR1 PvuII CC genotype, indicating that the correlations observed were due mainly to this group of women. There was no relationship between dietary isoflavones and plasma estradiol and no association was found between any of the dietary, urinary, and serum phytoestrogen and plasma SHBG or between these factors and polymorphisms in CYP19, SHBG, and COMT. We conclude that higher isoflavone exposure is associated with lower plasma estradiol in postmenopausal women and that this preliminary study is suggestive of the involvement of diet-gene interactions.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Dieta , Estradiol/sangre , Fitoestrógenos/metabolismo , Anciano , Análisis de Varianza , Biomarcadores de Tumor/sangre , Cromatografía de Gases , Estudios Transversales , Europa (Continente) , Femenino , Genotipo , Humanos , Espectrometría de Masas , Persona de Mediana Edad , Fitoestrógenos/administración & dosificación , Polimorfismo Genético , Posmenopausia , Estudios Prospectivos , Globulina de Unión a Hormona Sexual/metabolismo , Estadísticas no Paramétricas
14.
Cancer Epidemiol Biomarkers Prev ; 14(7): 1828-31, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16030124

RESUMEN

A substantial proportion of the familial risk of breast cancer may be due to genetic variants, each contributing a small effect. The protein encoded by ERCC2 is a key enzyme involved in nucleotide excision repair, in which gene defects could lead to cancer prone syndromes such as Xeroderma pigmentosum D. We have examined the association between single nucleotide polymorphisms in the ERCC2 gene and the incidence of invasive breast cancer in three case-control series, with a maximum of 3,634 patients and of 3,340 controls. None of the three single nucleotide polymorphisms were significantly associated with the incidence of breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Polimorfismo de Nucleótido Simple/genética , Vigilancia de la Población/métodos , Factores de Transcripción/genética , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Proteína de la Xerodermia Pigmentosa del Grupo D
15.
Cell Signal ; 16(2): 145-56, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14636885

RESUMEN

Bcr-Abl protein tyrosine kinase (PTK) activity is a feature of chronic myeloid leukaemia and confers a survival advantage on haemopoietic progenitor cells. We have expressed conditional mutant of the Bcr-Abl PTK in the FDCP-Mix A4 multipotent haematopoietic cell line in order to examine the molecular mechanisms whereby Bcr-Abl PTK leads to enhanced cell survival under conditions in which normal cells die. Activation of Bcr-Abl PTK does not phosphorylate or activate either ERK-1/2 or JAK-2/STAT-5b, suggesting that these signal transduction pathways are not involved in Abl PTK-mediated suppression of apoptosis in FDCP-Mix cells. However, protein kinase C (PKC) does have a role to play. Inhibition of PKC results in a reversal of Bcr-Abl PTK-mediated survival in the absence of growth factor and Bcr-Abl stimulates translocation of the PKCbetaII isoform to the nucleus. Furthermore, expression of a constitutively activated PKCbetaII in haemopoietic progenitor FDCP-Mix cells stimulates enhanced cell survival when IL-3 is withdrawn. However, expression of this constitutively activated PKC isoform does not suppress cytotoxic drug-induced apoptosis. Thus Bcr-Abl PTK has pleiotropic effects which can suppress cell death induced by a number of stimuli.


Asunto(s)
Apoptosis/fisiología , Supervivencia Celular/fisiología , Células Madre Hematopoyéticas/metabolismo , Proteínas de la Leche , Células Madre Multipotentes/metabolismo , Proteína Quinasa C/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas , Técnicas de Cocultivo , Proteínas de Unión al ADN/metabolismo , Proteínas de Fusión bcr-abl , Humanos , Interleucina-3/deficiencia , Interleucina-3/metabolismo , Janus Quinasa 2 , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Mutación , Fosforilación , Proteína Quinasa C beta , Factor de Transcripción STAT5 , Transducción de Señal , Transactivadores/metabolismo
16.
Vasc Health Risk Manag ; 1(2): 149-53, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-17315401

RESUMEN

OBJECTIVES: Nonsteroidal antiinflammatory drugs (NSAIDS) have been shown to retard aneurysm growth in animal models. In vitro studies have shown an inhibitory effect of NSAIDS on matrix metalloproteinase-9, interleukin-1beta, and IL-6 mediated arterial wall elastolysis. The aim of this study was to investigate the effects of NSAIDs on arterial stiffness, a surrogate marker of elastolysis. METHODS: 447 subjects enrolled in a community-based abdominal aortic aneurysm (AAA) screening program were assessed for age, blood pressure, smoking status, and drug history. Aortic diameter and stiffness were measured by M-Mode ultrasound. The concentration of the amino-terminal propeptide of type III procollagen was used as a proxy measurement of type III collagen turnover. RESULTS: NSAID ingestion was significantly (p = 0.006) associated with increased aortic wall stiffness after adjusting for age, aortic diameter, blood pressure, and smoking status. No such effect was seen for beta-blockers, calcium channel antagonists, nitrates, angiotensin-converting enzyme inhibitors, diuretics, or antiplatelet agents. DISCUSSION: These novel data show that NSAIDS are associated with increased aortic stiffness, possibly through the effects of cytokine mediated elastolysis. This in turn may prevent aortic expansion and the development of AAA.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Aorta Abdominal/efectos de los fármacos , Aneurisma de la Aorta Abdominal/patología , Anciano , Antiinflamatorios no Esteroideos/uso terapéutico , Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/patología , Aneurisma de la Aorta Abdominal/sangre , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/prevención & control , Estudios de Casos y Controles , Adaptabilidad/efectos de los fármacos , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/sangre , Procolágeno/sangre , Estudios Prospectivos , Ultrasonografía
17.
Am J Trop Med Hyg ; 92(4): 875-878, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25667056

RESUMEN

Undifferentiated febrile illnesses (UFIs) are common in low- and middle-income countries. We prospectively investigated the causes of UFIs in 627 patients presenting to a tertiary referral hospital in Kathmandu, Nepal. Patients with microbiologically confirmed enteric fever (218 of 627; 34.8%) randomized to gatifloxacin or ofloxacin treatment were previously reported. We randomly selected 125 of 627 (20%) of these UFI patients, consisting of 96 of 409 (23%) cases with sterile blood cultures and 29 of 218 (13%) cases with enteric fever, for additional diagnostic investigations. We found serological evidence of acute murine typhus in 21 of 125 (17%) patients, with 12 of 21 (57%) patients polymerase chain reaction (PCR)-positive for Rickettsia typhi. Three UFI cases were quantitative PCR-positive for Rickettsia spp., two UFI cases were seropositive for Hantavirus, and one UFI case was seropositive for Q fever. Fever clearance time (FCT) for rickettsial infection was 44.5 hours (interquartile range = 26-66 hours), and there was no difference in FCT between ofloxacin or gatifloxacin. Murine typhus represents an important cause of predominantly urban UFIs in Nepal, and fluoroquinolones seem to be an effective empirical treatment.


Asunto(s)
Antibacterianos/uso terapéutico , Fiebre Q/epidemiología , Infecciones por Rickettsia/epidemiología , Fiebre Tifoidea/epidemiología , Tifus Endémico Transmitido por Pulgas/epidemiología , Fiebre , Fluoroquinolonas/uso terapéutico , Gatifloxacina , Humanos , Nepal/epidemiología , Ofloxacino/uso terapéutico , Estudios Prospectivos , Fiebre Q/tratamiento farmacológico , Infecciones por Rickettsia/tratamiento farmacológico , Fiebre Tifoidea/tratamiento farmacológico , Tifus Endémico Transmitido por Pulgas/tratamiento farmacológico
18.
Tuberculosis (Edinb) ; 95(5): 575-80, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26156785

RESUMEN

Tuberculosis (TB) is an important cause of morbidity and mortality worldwide. Granzymes (gzms) are proteases mainly found in cytotoxic lymphocytes, but also extracellularly. While the role of gzms in target cell death has been widely characterized, considerable evidence points towards broader roles related to infectious and inflammatory responses. To investigate the expression of the gzms in TB, intracellular gzms A, B and K were measured by flow cytometry in lymphocyte populations from peripheral blood mononuclear cells from 18 TB patients and 12 healthy donors from Bangladesh, and extracellular levels of gzmA and B were measured in serum from 58 TB patients and 31 healthy controls. TB patients showed increased expression of gzmA in CD8(+) T, CD4(+) T and CD56(+) T, but not NK, cells, and of gzmB in CD8(+) T cells, when compared to controls. GzmK expression was not altered in TB patients in any lymphocyte subset. The extracellular levels of gzmA and, to a lesser extent, of gzmB, were increased in TB patients, but did not correlate with intracellular gzm expression in lymphocyte subsets. Our results reveal enhanced intra- and extracellular expression of gzmA and B in patients with pulmonary TB, suggesting that gzms are part of the host response to tuberculosis.


Asunto(s)
Granzimas/sangre , Linfocitos T/enzimología , Tuberculosis/sangre , Tuberculosis/enzimología , Adulto , Bangladesh , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Citometría de Flujo , Interacciones Huésped-Patógeno , Humanos , Masculino , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/patogenicidad , Linfocitos T/inmunología , Linfocitos T/microbiología , Tuberculosis/diagnóstico , Tuberculosis/inmunología , Tuberculosis/microbiología , Regulación hacia Arriba , Adulto Joven
19.
Cancer Epidemiol Biomarkers Prev ; 13(5): 698-708, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15159299

RESUMEN

Subjects of this study consisted of 333 women (aged 45-75 years) drawn from a large United Kingdom prospective study of diet and cancer, the European Prospective Investigation of Cancer and Nutrition-Norfolk study. Using newly developed gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry methods incorporating triply (13)C-labeled standards, seven phytoestrogens (daidzein, genistein, glycitein, O-desmethylangolensin, equol, enterodiol, and enterolactone) were measured in 114 spot urines and 97 available serum samples from women who later developed breast cancer. Results were compared with those from 219 urines and 187 serum samples from healthy controls matched by age and date of recruitment. Dietary levels were low, but even so, mean serum levels of phytoestrogens were up to 600 times greater than postmenopausal estradiol levels. Phytoestrogen concentrations in spot urine (adjusted for urinary creatinine) correlated strongly with that in serum, with Pearson correlation coefficients > 0.8. There were significant relationships (P < 0.02) between both urinary and serum concentrations of isoflavones across increasing tertiles of dietary intakes. Urinary enterodiol and enterolactone and serum enterolactone were significantly correlated with dietary fiber intake (r = 0.13-0.29). Exposure to all isoflavones was associated with increased breast cancer risk, significantly so for equol and daidzein. For a doubling of levels, odds ratios increased by 20-45% [log(2) odds ratio = 1.34 (1.06-1.70; P = 0.013) for urine equol, 1.46 (1.05-2.02; P = 0.024) for serum equol, and 1.22 (1.01-1.48; P = 0.044) for serum daidzein]. These estimates of risk are similar to those established for estrogens and androgens in postmenopausal breast cancer but need confirmation in larger studies.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Suplementos Dietéticos , Isoflavonas/metabolismo , Preparaciones de Plantas/metabolismo , Adulto , Anciano , Análisis de Varianza , Estudios de Casos y Controles , Dieta , Humanos , Incidencia , Isoflavonas/sangre , Isoflavonas/orina , Persona de Mediana Edad , Oportunidad Relativa , Fitoestrógenos , Preparaciones de Plantas/sangre , Preparaciones de Plantas/orina , Probabilidad , Pronóstico , Estudios Prospectivos , Valores de Referencia , Sistema de Registros , Medición de Riesgo , Sensibilidad y Especificidad , Reino Unido/epidemiología
20.
Am J Trop Med Hyg ; 67(1): 102-6, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12363051

RESUMEN

Dengue is an increasingly important cause of morbidity and mortality in the tropics, with more than a billion people at risk each year. Immunologic enhancement is thought to contribute to disease pathogenesis. Only a very small proportion of infected individuals develop life-threatening dengue hemorrhagic fever (DHF). In a large case-control study with 400 DHF patients and 300 matched controls, we have assessed five polymorphic non-HLA host genetic factors that might influence susceptibility to DHF. The less frequent t allele of a variant at position 352 of the vitamin D receptor (VDR) gene was associated with resistance to severe dengue (P = 0.03). Homozygotes for the arginine variant at position 131 of the Fc gammaRIIA gene, who have less capacity to opsonize IgG2 antibodies, may also be protected from DHF (one-tailed P = 0.03). No associations were found with polymorphisms in the mannose binding lectin, interleukin-1 (IL-4), and IL-1 receptor antagonist genes. Further studies to confirm these associations are warranted.


Asunto(s)
Dengue/genética , Predisposición Genética a la Enfermedad , Receptores de Calcitriol/genética , Receptores de IgG/genética , Secuencia de Bases , Estudios de Casos y Controles , Niño , Cartilla de ADN , Dengue/epidemiología , Genotipo , Humanos , Polimorfismo Genético , Vietnam/epidemiología
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