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1.
Int J Environ Health Res ; : 1-12, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38037746

RESUMEN

Infection with multidrug resistant bacteria is a significant public health concern. Bacteria culture of water samples (n=120) collected in San Cristobal River, Philippines, showed that half (n=60) were positive for Salmonella spp. Screening of all isolates (n=179) for susceptibility to antibiotics showed that most (76.4%; n=113) were positive for class 1 integrons, of which one isolate was also positive for the class 2 integron. The presence of class 1 integrons was associated with resistance to antibiotics (p<0.05). Sequencing of class 1 integron variable regions (VRs) differeciated 11 gene cassettes: dfrA1 or dfrA17; aadA1 or aadA2; blaCTX-M-2 or bla-OXA-1; SmdAB; CmlA1 and aaC 3-Id. However, sequencing of class 2 integron VR differenciated estX, sat2, and aadA1. These results provide insights into evolutionary changes within bacterial multidrug resistant cassettes, more accurately to estimate heath risk associated with the river water. .

2.
Ecotoxicol Environ Saf ; 197: 110612, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32302860

RESUMEN

In this paper, we deciphered the core resistome disseminating from hospital wastewater to the aquatic environment by characterising the resistome, plasmidome, mobilome and virulome using metagenomic analysis. This study also elucidated different environmental resistome risks using shotgun-metagenomic assembly. The results showed that clinically relevant taxa were found in assessed matrices (Salmonella spp., Acinetobacter spp, Escherichia-Shigella spp., Pseudomonas spp., Staphylococcus spp. and Vibrio spp.). For the plasmidome, we found 249 core plasmidome sequences that were shared among all assessed matrices. The core mobilome of 2424 mobile genetic elements shared among all assessed matrices was found. Regarding the virulome, we found 148 core virulence factors shared among all assessed samples, and the core virulome content was consistently shared across the most abundant bacterial genera. Although influent of wastewater showed considerable higher relative bacterial abundance (P = 0.008), hospital wastewater showed significant higher environmental resistome risk scores against all other assessed matrices, with an average of 46.34% (P = 0.001). These results suggest hospital wastewater, effluent and sewage sludge should be subjected to stringent mitigating measures to minimise such dissemination.


Asunto(s)
Bacterias/genética , Bacterias/patogenicidad , Aguas Residuales/microbiología , Contaminantes del Agua/toxicidad , Bacterias/aislamiento & purificación , Farmacorresistencia Bacteriana/genética , Hospitales , Humanos , Secuencias Repetitivas Esparcidas , Metagenómica , Plásmidos/genética , Medición de Riesgo , Aguas del Alcantarillado/microbiología , Factores de Virulencia , Aguas Residuales/toxicidad
3.
Emerg Infect Dis ; 25(7): 1401-1403, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31211680

RESUMEN

We documented a 6-fold increase in the frequency of nontuberculous mycobacteria isolated from clinical samples in Botswana during 2011-2014. Because antituberculosis treatment is often initiated only on the basis of acid-fast bacilli smear-positive microscopy results, some patients with nontuberculous mycobacterial infections might have received inappropriate treatment.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas , Adolescente , Adulto , Factores de Edad , Botswana/epidemiología , Niño , Preescolar , Femenino , Historia del Siglo XXI , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Infecciones por Mycobacterium no Tuberculosas/historia , Vigilancia en Salud Pública , Adulto Joven
4.
Molecules ; 24(11)2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-31167480

RESUMEN

Lauridia tetragona (L.f) R.H. Archer is routinely used in traditional medicine; however, its hepatoprotective property is yet to be scientifically proven. To this effect, the hepatoprotective activity of the polyphenolic-rich fractions (PPRFs) was investigated against acetaminophen (APAP) injured HepG2 cells. The ability of the PPRF to scavenge free radicals was tested against 2,2-diphenyl-1-picrylhydrazyl (DPPH), and [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonicacid)] (ABTS). The ferric ion reducing power (FRAP) was also evaluated as a cell-free antioxidant assay. The hepatoprotective activity was then investigated by observing the effect of PPRFs against APAP-induced reduction in cell viability of HepG2 cells. The concentrations of alanine aminotransferase (AST), aspartate aminotransferase (ALT) and lactate dehydrogenase (LDH) released into the medium were evaluated while the underlying mechanism was further explored through western blot analysis. Thereafter, the isolated PPRFs were identified using UHPLC-QToF-MS. All six fractions of the PPRFs isolated showed significant antioxidant properties that were evident by the effective scavenging of DPPH, ABTS, and higher FRAP. The results indicated that PPRF pretreatments ameliorated APAP-induced hepatocellular injury by significantly inhibiting the leakage of AST, ALT, and LDH into the medium. The most active fractions for hepatoprotection were PPRF4 and PPRF6 with IC50 of 50.243 ± 8.03 and 154.59 ± 1.9 µg/mL, respectively. PPRFs markedly increased activities of liver superoxide dismutase, total antioxidant capacity, and liver glutathione concentration. Both PPRF4 and PPRF6 significantly increased the expression of Nrf2 and translocation. The LC-MS analysis revealed the presence of a wide variety of polyphenolics such as coumarin, ferulic acid, and caffeine among the dominant constituents. In conclusion, this study demonstrates that the isolated PPRFs have potential hepatoprotective activity that may be due to the increased expression of antioxidative genes dependent on Nrf2.


Asunto(s)
Acetaminofén/efectos adversos , Celastraceae/química , Extractos Vegetales/farmacología , Polifenoles/farmacología , Sustancias Protectoras/farmacología , Alanina Transaminasa/metabolismo , Antioxidantes/química , Antioxidantes/farmacología , Aspartato Aminotransferasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas , Relación Dosis-Respuesta a Droga , Antagonismo de Drogas , Activación Enzimática/efectos de los fármacos , Glutatión/metabolismo , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Peroxidación de Lípido/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Polifenoles/química , Sustancias Protectoras/química
5.
Lancet Oncol ; 17(9): 1203-16, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27599138

RESUMEN

BACKGROUND: 30-day mortality might be a useful indicator of avoidable harm to patients from systemic anticancer treatments, but data for this indicator are limited. The Systemic Anti-Cancer Therapy (SACT) dataset collated by Public Health England allows the assessment of factors affecting 30-day mortality in a national patient population. The aim of this first study based on the SACT dataset was to establish national 30-day mortality benchmarks for breast and lung cancer patients receiving SACT in England, and to start to identify where patient care could be improved. METHODS: In this population-based study, we included all women with breast cancer and all men and women with lung cancer residing in England, who were 24 years or older and who started a cycle of SACT in 2014 irrespective of the number of previous treatment cycles or programmes, and irrespective of their position within the disease trajectory. We calculated 30-day mortality after the most recent cycle of SACT for those patients. We did logistic regression analyses, adjusting for relevant factors, to examine whether patient, tumour, or treatment-related factors were associated with the risk of 30-day mortality. For each cancer type and intent, we calculated 30-day mortality rates and patient volume at the hospital trust level, and contrasted these in a funnel plot. FINDINGS: Between Jan 1, and Dec, 31, 2014, we included 23 228 patients with breast cancer and 9634 patients with non-small cell lung cancer (NSCLC) in our regression and trust-level analyses. 30-day mortality increased with age for both patients with breast cancer and patients with NSCLC treated with curative intent, and decreased with age for patients receiving palliative SACT (breast curative: odds ratio [OR] 1·085, 99% CI 1·040-1·132; p<0·0001; NSCLC curative: 1·045, 1·013-1·079; p=0·00033; breast palliative: 0·987, 0·977-0·996; p=0·00034; NSCLC palliative: 0·987, 0·976-0·998; p=0·0015). 30-day mortality was also significantly higher for patients receiving their first reported curative or palliative SACT versus those who received SACT previously (breast palliative: OR 2·326 99% CI 1·634-3·312; p<0·0001; NSCLC curative: 3·371, 1·554-7·316; p<0·0001; NSCLC palliative: 2·667, 2·109-3·373; p<0·0001), and for patients with worse general wellbeing (performance status 2-4) versus those who were generally well (breast curative: 6·057, 1·333-27·513; p=0·0021; breast palliative: 6·241, 4·180-9·319; p<0·0001; NSCLC palliative: 3·384, 2·276-5·032; p<0·0001). We identified trusts with mortality rates in excess of the 95% control limits; this included seven for curative breast cancer, four for palliative breast cancer, five for curative NSCLC, and seven for palliative NSCLC. INTERPRETATION: Our findings show that several factors affect the risk of early mortality of breast and lung cancer patients in England and that some groups are at a substantially increased risk of 30-day mortality. The identification of hospitals with significantly higher 30-day mortality rates should promote review of clinical decision making in these hospitals. Furthermore, our results highlight the importance of collecting routine data beyond clinical trials to better understand the factors placing patients at higher risk of 30-day mortality, and ultimately improve clinical decision making. Our insights into the factors affecting risk of 30-day mortality will help treating clinicians and their patients predict the balance of harms and benefits associated with SACT. FUNDING: Public Health England.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Neoplasias Pulmonares/mortalidad , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/patología , Inglaterra/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia , Factores de Tiempo
6.
Lancet ; 383(9917): 603-13, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24224997

RESUMEN

BACKGROUND: The TARGIT-A trial compared risk-adapted radiotherapy using single-dose targeted intraoperative radiotherapy (TARGIT) versus fractionated external beam radiotherapy (EBRT) for breast cancer. We report 5-year results for local recurrence and the first analysis of overall survival. METHODS: TARGIT-A was a randomised, non-inferiority trial. Women aged 45 years and older with invasive ductal carcinoma were enrolled and randomly assigned in a 1:1 ratio to receive TARGIT or whole-breast EBRT, with blocks stratified by centre and by timing of delivery of targeted intraoperative radiotherapy: randomisation occurred either before lumpectomy (prepathology stratum, TARGIT concurrent with lumpectomy) or after lumpectomy (postpathology stratum, TARGIT given subsequently by reopening the wound). Patients in the TARGIT group received supplemental EBRT (excluding a boost) if unforeseen adverse features were detected on final pathology, thus radiotherapy was risk-adapted. The primary outcome was absolute difference in local recurrence in the conserved breast, with a prespecified non-inferiority margin of 2·5% at 5 years; prespecified analyses included outcomes as per timing of randomisation in relation to lumpectomy. Secondary outcomes included complications and mortality. This study is registered with ClinicalTrials.gov, number NCT00983684. FINDINGS: Patients were enrolled at 33 centres in 11 countries, between March 24, 2000, and June 25, 2012. 1721 patients were randomised to TARGIT and 1730 to EBRT. Supplemental EBRT after TARGIT was necessary in 15·2% [239 of 1571] of patients who received TARGIT (21·6% prepathology, 3·6% postpathology). 3451 patients had a median follow-up of 2 years and 5 months (IQR 12-52 months), 2020 of 4 years, and 1222 of 5 years. The 5-year risk for local recurrence in the conserved breast was 3·3% (95% CI 2·1-5·1) for TARGIT versus 1·3% (0·7-2·5) for EBRT (p=0·042). TARGIT concurrently with lumpectomy (prepathology, n=2298) had much the same results as EBRT: 2·1% (1·1-4·2) versus 1·1% (0·5-2·5; p=0·31). With delayed TARGIT (postpathology, n=1153) the between-group difference was larger than 2·5% (TARGIT 5·4% [3·0-9·7] vs EBRT 1·7% [0·6-4·9]; p=0·069). Overall, breast cancer mortality was much the same between groups (2·6% [1·5-4·3] for TARGIT vs 1·9% [1·1-3·2] for EBRT; p=0·56) but there were significantly fewer non-breast-cancer deaths with TARGIT (1·4% [0·8-2·5] vs 3·5% [2·3-5·2]; p=0·0086), attributable to fewer deaths from cardiovascular causes and other cancers. Overall mortality was 3·9% (2·7-5·8) for TARGIT versus 5·3% (3·9-7·3) for EBRT (p=0·099). Wound-related complications were much the same between groups but grade 3 or 4 skin complications were significantly reduced with TARGIT (four of 1720 vs 13 of 1731, p=0·029). INTERPRETATION: TARGIT concurrent with lumpectomy within a risk-adapted approach should be considered as an option for eligible patients with breast cancer carefully selected as per the TARGIT-A trial protocol, as an alternative to postoperative EBRT. FUNDING: University College London Hospitals (UCLH)/UCL Comprehensive Biomedical Research Centre, UCLH Charities, National Institute for Health Research Health Technology Assessment programme, Ninewells Cancer Campaign, National Health and Medical Research Council, and German Federal Ministry of Education and Research.


Asunto(s)
Neoplasias de la Mama/radioterapia , Carcinoma Ductal de Mama/radioterapia , Anciano , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/mortalidad , Carcinoma Ductal de Mama/cirugía , Femenino , Humanos , Cuidados Intraoperatorios/métodos , Cuidados Intraoperatorios/mortalidad , Estimación de Kaplan-Meier , Mastectomía Segmentaria/métodos , Mastectomía Segmentaria/mortalidad , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/prevención & control , Radioterapia/métodos , Radioterapia/mortalidad , Resultado del Tratamiento
7.
Lancet Oncol ; 14(11): 1086-1094, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24055415

RESUMEN

BACKGROUND: 5-year results of the UK Standardisation of Breast Radiotherapy (START) trials suggested that lower total doses of radiotherapy delivered in fewer, larger doses (fractions) are at least as safe and effective as the historical standard regimen (50 Gy in 25 fractions) for women after primary surgery for early breast cancer. In this prespecified analysis, we report the 10-year follow-up of the START trials testing 13 fraction and 15 fraction regimens. METHODS: From 1999 to 2002, women with completely excised invasive breast cancer (pT1-3a, pN0-1, M0) were enrolled from 35 UK radiotherapy centres. Patients were randomly assigned to a treatment regimen after primary surgery followed by chemotherapy and endocrine treatment (where prescribed). Randomisation was computer-generated and stratified by centre, type of primary surgery (breast-conservation surgery or mastectomy), and tumour bed boost radiotherapy. In START-A, a regimen of 50 Gy in 25 fractions over 5 weeks was compared with 41·6 Gy or 39 Gy in 13 fractions over 5 weeks. In START-B, a regimen of 50 Gy in 25 fractions over 5 weeks was compared with 40 Gy in 15 fractions over 3 weeks. Eligibility criteria included age older than 18 years and no immediate surgical reconstruction. Primary endpoints were local-regional tumour relapse and late normal tissue effects. Analysis was by intention to treat. Follow-up data are still being collected. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN59368779. FINDINGS: START-A enrolled 2236 women. Median follow-up was 9·3 years (IQR 8·0-10·0), after which 139 local-regional relapses had occurred. 10-year rates of local-regional relapse did not differ significantly between the 41·6 Gy and 50 Gy regimen groups (6·3%, 95% CI 4·7-8·5 vs 7·4%, 5·5-10·0; hazard ratio [HR] 0·91, 95% CI 0·59-1·38; p=0·65) or the 39 Gy (8·8%, 95% CI 6·7-11·4) and 50 Gy regimen groups (HR 1·18, 95% CI 0·79-1·76; p=0·41). In START-A, moderate or marked breast induration, telangiectasia, and breast oedema were significantly less common normal tissue effects in the 39 Gy group than in the 50 Gy group. Normal tissue effects did not differ significantly between 41·6 Gy and 50 Gy groups. START-B enrolled 2215 women. Median follow-up was 9·9 years (IQR 7·5-10·1), after which 95 local-regional relapses had occurred. The proportion of patients with local-regional relapse at 10 years did not differ significantly between the 40 Gy group (4·3%, 95% CI 3·2-5·9) and the 50 Gy group (5·5%, 95% CI 4·2-7·2; HR 0·77, 95% CI 0·51-1·16; p=0·21). In START-B, breast shrinkage, telangiectasia, and breast oedema were significantly less common normal tissue effects in the 40 Gy group than in the 50 Gy group. INTERPRETATION: Long-term follow-up confirms that appropriately dosed hypofractionated radiotherapy is safe and effective for patients with early breast cancer. The results support the continued use of 40 Gy in 15 fractions, which has already been adopted by most UK centres as the standard of care for women requiring adjuvant radiotherapy for invasive early breast cancer. FUNDING: Cancer Research UK, UK Medical Research Council, UK Department of Health.


Asunto(s)
Neoplasias de la Mama/radioterapia , Fraccionamiento de la Dosis de Radiación , Recurrencia Local de Neoplasia/radioterapia , Guías de Práctica Clínica como Asunto/normas , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Mastectomía , Mastectomía Segmentaria , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/terapia , Estadificación de Neoplasias , Pronóstico , Radioterapia Adyuvante , Estándares de Referencia , Tasa de Supervivencia
8.
Gastroenterol Res Pract ; 2023: 1906782, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37663241

RESUMEN

Objective: To estimate gastroenteritis disease and its etiological agents in children under the age of 5 years living in South Africa. Methods: A mini literature review of pertinent articles published in ScienceDirect, PubMed, GoogleScholar, and Scopus was conducted using search terms: "Gastroenteritis in children," "Gastroenteritis in the world," Gastroenteritis in South Africa," "Prevalence of gastroenteritis," "Epidemiological surveillance of gastroenteritis in the world," and "Causes of gastroenteritis". Results: A total of 174 published articles were included in this mini review. In the last 20 years, the mortality rate resulting from diarrhea in children under the age of 5 years has declined and this is influenced by improved hygiene practices, awareness programs, an improved water and sanitation supply, and the availability of vaccines. More modern genomic amplification techniques were used to re-analyze stool specimens collected from children in eight low-resource settings in Asia, South America, and Africa reported improved sensitivity of pathogen detection to about 65%, that viruses were the main etiological agents in patients with diarrhea aged from 0 to 11 months but that Shigella, followed by sapovirus and enterotoxigenic Escherichia coli had a high incidence in children aged 12-24 months. In addition, co-infections were noted in nearly 10% of diarrhea cases, with rotavirus and Shigella being the main co-infecting agents together with adenovirus, enteropathogenic E. coli, Clostridium jejuni, or Clostridium coli. Conclusions: This mini review outlines the epidemiology and trends relating to parasitic, viral, and bacterial agents responsible for gastroenteritis in children in South Africa. An increase in sequence-independent diagnostic approaches will improve the identification of pathogens to resolve undiagnosed cases of gastroenteritis. Emerging state and national surveillance systems should focus on improving the identification of gastrointestinal pathogens in children and the development of further vaccines against gastrointestinal pathogens.

9.
Antibiotics (Basel) ; 12(1)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36671332

RESUMEN

Aeromonas rivipollensis is an emerging pathogen linked to a broad range of infections in humans. Due to the inability to accurately differentiate Aeromonas species using conventional techniques, in-depth comparative genomics analysis is imperative to identify them. This study characterized 4 A. rivipollensis strains that were isolated from river water in Johannesburg, South Africa, by whole-genome sequencing (WGS). WGS was carried out, and taxonomic classification was employed to profile virulence and antibiotic resistance (AR). The AR profiles of the A. rivipollensis genomes consisted of betalactams and cephalosporin-resistance genes, while the tetracycline-resistance gene (tetE) was only determined to be in the G87 strain. A mobile genetic element (MGE), transposons TnC, was determined to be in this strain that mediates tetracycline resistance MFS efflux tetE. A pangenomic investigation revealed the G87 strain's unique characteristic, which included immunoglobulin A-binding proteins, extracellular polysialic acid, and exogenous sialic acid as virulence factors. The identified polysialic acid and sialic acid genes can be associated with antiphagocytic and antibactericidal properties, respectively. MGEs such as transposases introduce virulence and AR genes in the A. rivipollensis G87 genome. This study showed that A. rivipollensis is generally resistant to a class of beta-lactams and cephalosporins. MGEs pose a challenge in some of the Aeromonas species strains and are subjected to antibiotics resistance and the acquisition of virulence genes in the ecosystem.

10.
Breast Cancer Res Treat ; 136(2): 503-11, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23065000

RESUMEN

Fulvestrant fIRst-line Study comparing endocrine Treatments is a phase II, randomized, open-label study comparing fulvestrant 500 mg with anastrozole 1 mg as first-line endocrine therapy for postmenopausal women with hormone receptor-positive (HR+) advanced breast cancer. At data cut-off, only 36 % of patients had progressed and the median time to progression (TTP) had not been reached for fulvestrant. Here, we report follow-up data for TTP for fulvestrant 500 mg versus anastrozole 1 mg. Key inclusion criteria were postmenopausal women with estrogen receptor-positive and/or progesterone receptor-positive locally advanced or metastatic breast cancer and no prior endocrine therapy. Key exclusion criteria were presence of life-threatening metastases and prior treatment with a non-approved drug. Fulvestrant was administered 500 mg/month plus 500 mg on day 14 of month 1; anastrozole was administered 1 mg/day. TTP was defined by modified Response Evaluation Criteria in Solid Tumors v1.0 before data cut-off for the primary analysis, and investigator opinion after data cut-off. Best overall response to subsequent therapy and serious adverse events are also reported. In total, 205 patients received fulvestrant 500 mg (n = 102) or anastrozole (n = 103). Follow-up analysis was performed when 79.5 % of patients had discontinued study treatment. Median TTP was 23.4 months for fulvestrant versus 13.1 months for anastrozole; a 34 % reduction in risk of progression (hazard ratio 0.66; 95 % confidence interval: 0.47, 0.92; P = 0.01). Best overall response to subsequent therapy and clinical benefit rate for subsequent endocrine therapy was similar between the treatment groups. No new safety concerns for fulvestrant 500 mg were documented. These longer-term, follow-up results confirm efficacy benefit for fulvestrant 500 mg versus anastrozole as first-line endocrine therapy for HR+ advanced breast cancer in terms of TTP, and, importantly, show similar best overall response rates to subsequent endocrine therapy.


Asunto(s)
Antineoplásicos Hormonales/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Estradiol/análogos & derivados , Nitrilos/administración & dosificación , Triazoles/administración & dosificación , Anastrozol , Antineoplásicos Hormonales/efectos adversos , Estradiol/administración & dosificación , Estradiol/efectos adversos , Femenino , Estudios de Seguimiento , Fulvestrant , Humanos , Estadificación de Neoplasias , Nitrilos/efectos adversos , Resultado del Tratamiento , Triazoles/efectos adversos
11.
Mutagenesis ; 27(6): 737-41, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22935224

RESUMEN

Previous studies from our laboratory have identified a link between intracellular topoisomerase IIα (topo IIα) levels and chromosomal radiosensitivity, as measured by the frequencies of chromatid breaks in the so-called G2-assay. Lower topo IIα levels were associated with reduced chromosomal radiosensitivity in cultured human cells. These findings supported a model, in which it is proposed that such chromatid breaks are the result of radiation-induced errors made by topoisomerase IIα during decatenation of chromatids. Studies from our and other laboratories, using the G2-assay, have shown that phytohaemagglutinin (PHA)-stimulated peripheral blood T-lymphocytes from 40% of female breast cancer cases show elevated chromatid break frequencies when exposed to a small standard dose of ionizing radiation, i.e. elevated above the 90th percentile of a group of female control samples. In the present study we have used a modified G2-assay to test whether elevated frequency of chromatid breaks in breast cancer cases is linked with elevated intracellular topo IIα level in PHA-stimulated T-lymphocytes, and also whether there is a general correlation between chromosomal radiosensitivity and topo IIα level. Our results confirm previous studies that 40% of breast cancer cases show elevated radiosensitivity as compared with controls. Also, the mean chromatid break frequency in breast cancer cases was significantly higher than in controls (P = 0.0001). We found that the mean topo IIα level in the cohort of breast cancer cases studied was significantly raised, as compared with controls (P = 0.0016), which could indicate a genetic propensity towards a raised intracellular production of topo IIα in these individuals. There was no direct correlation between chromosomal radiosensitivity and topo IIα level for individual samples either in the breast cancer cohort or in controls. However, a comparison between control and breast cancer samples shows a higher mean topo IIα level in breast cancer samples that correlates with the elevated mean chromatid break frequency seen in these patient samples. We found no meaningful correlations between either chromatid break frequency or topo IIα level and either tumour grade or hormone status. We conclude that elevated intracellular topo IIα level is likely to be a significant factor in determining the chromosomal response of stimulated T-lymphocytes from certain breast cancer cases.


Asunto(s)
Antígenos de Neoplasias/análisis , Neoplasias de la Mama/genética , Daño del ADN , ADN-Topoisomerasas de Tipo II/análisis , Proteínas de Unión al ADN/análisis , Tolerancia a Radiación/genética , Linfocitos T/efectos de la radiación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Estudios de Casos y Controles , Línea Celular Tumoral , Cromátides/genética , Cromosomas Humanos , Femenino , Humanos , Persona de Mediana Edad , Radiación Ionizante , Linfocitos T/metabolismo
12.
Lancet ; 376(9735): 91-102, 2010 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-20570343

RESUMEN

BACKGROUND: After breast-conserving surgery, 90% of local recurrences occur within the index quadrant despite the presence of multicentric cancers elsewhere in the breast. Thus, restriction of radiation therapy to the tumour bed during surgery might be adequate for selected patients. We compared targeted intraoperative radiotherapy with the conventional policy of whole breast external beam radiotherapy. METHODS: Having safely piloted the new technique of single-dose targeted intraoperative radiotherapy with Intrabeam, we launched the TARGIT-A trial on March 24, 2000. In this prospective, randomised, non-inferiority trial, women aged 45 years or older with invasive ductal breast carcinoma undergoing breast-conserving surgery were enrolled from 28 centres in nine countries. Patients were randomly assigned in a 1:1 ratio to receive targeted intraoperative radiotherapy or whole breast external beam radiotherapy, with blocks stratified by centre and by timing of delivery of targeted intraoperative radiotherapy. Neither patients nor investigators or their teams were masked to treatment assignment. Postoperative discovery of predefined factors (eg, lobular carcinoma) could trigger addition of external beam radiotherapy to targeted intraoperative radiotherapy (in an expected 15% of patients). The primary outcome was local recurrence in the conserved breast. The predefined non-inferiority margin was an absolute difference of 2.5% in the primary endpoint. All randomised patients were included in the intention-to-treat analysis. This trial is registered with ClinicalTrials.gov, number NCT00983684. FINDINGS: 1113 patients were randomly allocated to targeted intraoperative radiotherapy and 1119 were allocated to external beam radiotherapy. Of 996 patients who received the allocated treatment in the targeted intraoperative radiotherapy group, 854 (86%) received targeted intraoperative radiotherapy only and 142 (14%) received targeted intraoperative radiotherapy plus external beam radiotherapy. 1025 (92%) patients in the external beam radiotherapy group received the allocated treatment. At 4 years, there were six local recurrences in the intraoperative radiotherapy group and five in the external beam radiotherapy group. The Kaplan-Meier estimate of local recurrence in the conserved breast at 4 years was 1.20% (95% CI 0.53-2.71) in the targeted intraoperative radiotherapy and 0.95% (0.39-2.31) in the external beam radiotherapy group (difference between groups 0.25%, -1.04 to 1.54; p=0.41). The frequency of any complications and major toxicity was similar in the two groups (for major toxicity, targeted intraoperative radiotherapy, 37 [3.3%] of 1113 vs external beam radiotherapy, 44 [3.9%] of 1119; p=0.44). Radiotherapy toxicity (Radiation Therapy Oncology Group grade 3) was lower in the targeted intraoperative radiotherapy group (six patients [0.5%]) than in the external beam radiotherapy group (23 patients [2.1%]; p=0.002). INTERPRETATION: For selected patients with early breast cancer, a single dose of radiotherapy delivered at the time of surgery by use of targeted intraoperative radiotherapy should be considered as an alternative to external beam radiotherapy delivered over several weeks. FUNDING: University College London Hospitals (UCLH)/UCL Comprehensive Biomedical Research Centre, UCLH Charities, National Institute for Health Research Health Technology Assessment programme, Ninewells Cancer Campaign, National Health and Medical Research Council, and German Federal Ministry of Education and Research (BMBF).


Asunto(s)
Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/radioterapia , Carcinoma Ductal de Mama/cirugía , Cuidados Intraoperatorios , Mastectomía Segmentaria , Anciano , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Dosificación Radioterapéutica , Radioterapia Adyuvante
13.
Breast Cancer Res Treat ; 128(3): 783-94, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21655990

RESUMEN

Metformin may reduce the incidence of breast cancer and enhance response to neoadjuvant chemotherapy in diabetic women. This trial examined the effects of metformin on Ki67 and gene expression in primary breast cancer. Non-diabetic women with operable invasive breast cancer received pre-operative metformin. A pilot cohort of eight patients had core biopsy of the cancer at presentation, a week later (without treatment; internal control), then following metformin 500-mg o.d. for 1 week increased to 1-g b.d. for a further week continued to surgery. A further 47 patients had core biopsy at diagnosis were randomized to metformin (the same dose regimen) or no drug, and 2 weeks later had core biopsy at surgery. Ki67 immunohistochemistry, transcriptome analysis on formalin-fixed paraffin-embedded cores and serum insulin determination were performed blinded to treatment. Seven patients (7/32, 21.9%) receiving metformin withdrew because of gastrointestinal upset. The mean percentage of cells staining for Ki67 fell significantly following metformin treatment in both the pilot cohort (P = 0.041, paired t-test) and in the metformin arm (P = 0.027, Wilcoxon rank test) but was unchanged in the internal control or metformin control arms. Messenger RNA expression was significantly downregulated by metformin for PDE3B (phosphodiesterase 3B, cGMP-inhibited; a critical regulator of cAMP levels that affect activation of AMP-activated protein kinase, AMPK), confirmed by immunohistochemistry, SSR3, TP53 and CCDC14. By ingenuity pathway analysis, the tumour necrosis factor receptor 1 (TNFR1) signaling pathway was most affected by metformin: TGFB and MEKK were upregulated and cdc42 downregulated; mTOR and AMPK pathways were also affected. Gene set analysis additionally revealed that p53, BRCA1 and cell cycle pathways also had reduced expression following metformin. Mean serum insulin remained stable in patients receiving metformin but rose in control patients. This trial presents biomarker evidence for anti-proliferative effects of metformin in women with breast cancer and provides support for therapeutic trials of metformin.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Metformina/farmacología , Metformina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 3/genética , Femenino , Perfilación de la Expresión Génica , Humanos , Insulina/sangre , Antígeno Ki-67/metabolismo , Persona de Mediana Edad , Reproducibilidad de los Resultados , Transducción de Señal/genética , Proteína p53 Supresora de Tumor/genética
14.
J Infect Dis ; 202 Suppl: S131-8, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20684693

RESUMEN

BACKGROUND: Rotavirus is considered to be the most common cause of serious acute dehydrating diarrhea worldwide. However, there is a scarcity of information on rotavirus disease burden in sub-Saharan Africa. METHODS: We conducted prospective, hospital-based surveillance for rotavirus diarrhea among children <5 years of age at the tertiary care Dr. George Mukhari Hospital (DGM) and at the Brits district Hospital (BH) in the Gauteng and North West Provinces in South Africa; we estimated that up to 80% of children <5 years of age in their catchment areas who are hospitalized for diarrhea are admitted to one of these hospitals. RESULTS: At DGM, 2553 children <5 years of age were admitted for diarrhea from January 2003 through December 2005, and 852 children <5 years of age were treated for diarrhea at BH during 2004-2005. We examined stool specimens from 450 children (53%) at BH and from 1870 children (73%) admitted to DGM. An estimated 22.8% (95% confidence interval [CI], 21.2%-24.5%) of the children hospitalized with diarrhea at DGM were rotavirus positive, and the corresponding figure at BH was 18.2% (95% CI, 14.9%-22.1%). Among children <5 years of age admitted to DGM for any reason, an estimated 5.5% (95% CI, 5.1%-6.0%) had rotavirus diarrhea. Our incidence estimates suggest that 1 in 43-62 children in the area is likely to be hospitalized with rotavirus diarrhea by 2 years of age. CONCLUSIONS: Prevention of serious rotavirus illness by vaccination will substantially reduce not only the disease burden among young children but also the case load in South African health care facilities.


Asunto(s)
Diarrea/epidemiología , Infecciones por Rotavirus/epidemiología , Preescolar , Diarrea/virología , Heces/virología , Hospitalización/estadística & datos numéricos , Hospitales/estadística & datos numéricos , Humanos , Incidencia , Lactante , Recién Nacido , Vigilancia de la Población , Estudios Prospectivos , Estaciones del Año , Sudáfrica/epidemiología , Factores de Tiempo
15.
J Infect Dis ; 202 Suppl: S258-62, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20684713

RESUMEN

Limited genotyping data are available for rotavirus strains in the Middle East. In this study, we investigated the molecular epidemiology of human rotavirus strains circulating in the Sultanate of Oman during 2005. Rotavirus was detected in 178 (57.4%) of 310 of the diarrheal stools of young children <5 years admitted to hospitals and outpatients clinics. Polyacrylamide gel electrophoresis demonstrated the cocirculation of 8 strains, although 2 strains predominated across the Sultanate. Genotyping revealed the presence of human rotavirus strains of types G1P[8], G2P[4], and G3P[8]. Several strains exhibited unusual combinations of G and P genotypes and RNA electropherotypes, indicating the likelihood of natural reassortment events occurring with a high frequency. In addition, the unusual P[10] genotype was identified among the rotavirus strains, in combination with the G1 type.


Asunto(s)
Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/virología , Rotavirus/genética , Preescolar , Electroforesis en Gel de Poliacrilamida , Genotipo , Humanos , Lactante , Omán/epidemiología , Rotavirus/clasificación
16.
J Infect Dis ; 202 Suppl: S49-54, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20684717

RESUMEN

A total of 215 nontypeable rotavirus samples collected from children <5 years of age by members of the African Rotavirus Network were characterized using reverse-transcription polymerase chain reaction analysis and sequencing. The most predominant strain identified was P[8]G1 (46.9%). Genotypes P[8]G10, P[8]G8, P[6]G8, and P[7]G5 were also detected at frequencies varying from 0.5% to 2.3%. This study suggests that reassortment of unusual G types into a background of globally common genotype P[8] strains may be a major mechanism of generating rotavirus diversity. Nucleotide substitutions at the P[8], P[6], and G1 primer binding sites accounted for the failure to type these strains initially. Hence, these findings highlight the need for regular evaluation of rotavirus genotyping methods.


Asunto(s)
Rotavirus/clasificación , Rotavirus/genética , Proteínas Virales/genética , África/epidemiología , Regulación Viral de la Expresión Génica/fisiología , Variación Genética , Genotipo , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/virología , Serotipificación , Proteínas Virales/metabolismo
17.
Antibiotics (Basel) ; 10(9)2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34572619

RESUMEN

BACKGROUND: Human-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) has mainly been reported in South African pig and chicken farms. The prevalence of antibiotic-resistant genes (ARGs), virulence factors (VFs), and multilocus sequence types (MLSTs) associated with HA-MRSA in cattle farms has not been reported. Consequently, this study characterised LA-MRSA and its spread from cattle farms into the environment. METHOD: Husbandry soil (HS), nearby river water (NRW), animal manure (AM) and animal drinking water (ADW) were collected on and around a cattle farm. Presumptive MRSA isolates were identified from these samples using CHROMagar media and genotyped as MRSA sequence types (STs), selected ARGs, and VFs, using polymerase chain reaction. An MLST-based dendrogram was generated to link the farm MRSA strains with those in a nearby river. RESULTS: The prevalence of MRSA was 30.61% for HS, 28.57% for ADW, 22.44% for NRW, and 10.20% for AM. Isolates from HS harboured the highest number of resistant genes, with 100% for mecA, 91.66% for ermA, and 58.33% for blaZ. However, no ermC or tetM genes were detected. MRSA isolates from AM harboured the lowest number of resistant genes. Only sec and seq enterotoxins were found in all the assessed MRSA isolates. MRSA from the farm revealed six STs (ST80, ST728, ST1931, ST2030, ST3247, and ST5440); all of STs belonged to clonal complex 80 (CC80). An MLST-based dendrogram based on the concatenated sequences of MLST genes under the maximum likelihood criterion revealed four clades of amalgamated MRSA isolates from various livestock environmental matrices, including the NRW. CONCLUSION: The results suggest that livestock environmental matrices might be reservoirs of MRSA that could subsequently disseminate through runoff to pollute water resources. Therefore, continued surveillance of HA-MRSA in livestock environments is warranted.

18.
Nat Prod Res ; 35(12): 1968-1976, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31393174

RESUMEN

A novel cycloartanol (1) and an acylated Sutherlandioside D (2) together with two known cycloartane derivatives, Sutherlandioside B (3) and Sutherlandioside A (4), were isolated from the aerial parts of Sutherlandia frutescens. The structures of these compounds were established by a combination of 1- and 2-D NMR techniques and further confirmed by high resolution ToF mass spectrometry (HRToFMS). Preliminary biological studies were also conducted to assess the activity of different plant extracts, fractions and compounds on cytokine expression. Compounds 1 and 2 prompted an increase in IL-6 expression while compound 4 showed a reduced IL-6 expression compared to the controls. Compound 1 is an effective suppressor of IL-10 expression. The plant compounds inhibited the expression of the two cytokines, IL-10 and TNFα. The results of the assays suggested that some components in the plant extract influence the immune system by suppressing the expression of IL-6, IL-10 and TNFα.


Asunto(s)
Citocinas/metabolismo , Fabaceae/química , Factores Inmunológicos/química , Factores Inmunológicos/farmacología , Evaluación Preclínica de Medicamentos , Fabaceae/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Plantas Medicinales/química , Triterpenos/química
19.
Breast Cancer Res ; 12(3): 106, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20497617

RESUMEN

Holliday junction recognition protein (HJURP) levels in breast cancer associate with both poor prognosis and an increased sensitivity to irradiation. Whilst, in part, this could be explained in relation to proliferation, it would not entirely account for the association with sensitivity to radiation. Thus, HJURP may have clinical potential as a marker of prognosis and radiation sensitivity; further validation with tissues from randomised controlled trials is needed. HJURP may represent the first in a class of proteins with roles in chromosome segregation and DNA repair that act as predictive biomarkers.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/radioterapia , Proteínas de Unión al ADN/genética , Tolerancia a Radiación/genética , Neoplasias de la Mama/diagnóstico , Reparación del ADN , Femenino , Humanos , Pronóstico
20.
Breast Cancer Res ; 12(6): R92, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21059212

RESUMEN

INTRODUCTION: Immunohistochemistry of primary breast cancer is routinely used to guide changes in therapy at the time of relapse. Retrospective reviews suggest that the estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor type 2 (HER2) receptor may differ between the primary and loco-regional recurrence or distant metastases. The Breast Recurrence In Tissues Study (BRITS) was a large, multicentre, prospective study to examine changes in ER, PR and HER2. METHODS: Matched primary and recurrent breast cancer tissue samples were prospectively collected from 205 women attending 20 institutions. Central laboratory immunohistochemical analysis of core biopsies and tissue microarrays of ER and PR using the Allred and Quickscore methods and HER2 (confirmed by fluorescence in situ hybridisation (FISH) for HER2 2+) were performed. RESULTS: From 205 consenting women, 18 (8.8%) did not have recurrent disease on biopsy, 35 were ineligible, 13 had insufficient paired tissue and 2 were excluded for safety reasons. Paired samples from 137 women, mean age 62.6 years (range 27-87 years), 83/137 (60.6%) postmenopausal with a median 92.2 months (range 5-327 months) from primary to recurrence and 88 (64.2%) as locoregional recurrence were successfully analysed. A switch in receptor status, in either direction, by Allred score, was identified for ER in 14 patients (10.2%; P = 0.983 Wilcoxon sign rank test), PR in 34 (24.8%; P = 0.003 Wilcoxon sign rank test) and HER2 in 4 (2.9%; P = 0.074 Wilcoxon sign rank test). There was no difference between locoregional or distant recurrence in the proportion who switched. The switch in receptor status led to a change in the subsequent treatment plan for 24 patients (17.5%). CONCLUSIONS: This prospective study confirms retrospective evidence that the management of relapsed breast cancer should include confirmatory tissue sampling and identify switches of ER, PR or HER2 which change therapeutic management for one in six patients.


Asunto(s)
Neoplasias de la Mama , Recurrencia Local de Neoplasia , Receptor ErbB-2/análisis , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Femenino , Expresión Génica , Humanos , Hibridación Fluorescente in Situ , Persona de Mediana Edad , Posmenopausia , Estudios Prospectivos , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/genética , Receptores de Progesterona/genética , Estadísticas no Paramétricas
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