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2.
Tech Coloproctol ; 14(2): 133-9, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20424879

RESUMEN

BACKGROUND: To assess the feasibility of the sentinel lymph node procedure in patients with rectal cancer extending to the anal canal. METHODS: Between January 2005 and April 2008, 15 patients with adenocarcinoma of the rectum with direct invasion of the anal canal and no clinical evidence of inguinal involvement were prospectively enrolled in the study. The sentinel node procedure consisted of a combination of preoperative radiocolloid lymphoscintigraphy and intraoperative detection of the inguinal sentinel node with a gamma probe. Patent blue dye was also used to facilitate direct identification of the blue-stained lymph node. After removal, the sentinel node was studied by hematoxylin-eosin staining and immunohistochemistry. RESULTS: Detection and removal of inguinal sentinel nodes was possible in all patients. Four patients (26.7%) had sentinel nodes identified as positive for metastatic adenocarcinoma. All positive cases also had metastases detected in perirectal lymph nodes; three of them developed hepatic or pulmonary metastases within 6 months after surgery. Of the 11 patients with negative sentinel nodes, only four (36.4%) also presented metastatic perirectal lymph nodes. Although none of the negative cases developed late inguinal metastases, three developed systemic or pelvic recurrence within 12 months after surgery. CONCLUSIONS: The standardized procedure was highly effective in sampling inguinal sentinel nodes in very low rectal cancers, allowing the detection of subclinical metastatic disease. Although this technique can be potentially useful for a subgroup of patients with isolated inguinal metastases, it cannot be routinely recommended for patients with rectal tumors invading the anal canal at this moment.


Asunto(s)
Adenocarcinoma/secundario , Canal Anal , Conducto Inguinal , Neoplasias del Recto/patología , Biopsia del Ganglio Linfático Centinela , Adenocarcinoma/epidemiología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Estudios Prospectivos , Neoplasias del Recto/epidemiología , Neoplasias del Recto/terapia
3.
Environ Monit Assess ; 141(1-3): 227-36, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17876714

RESUMEN

The lichen transplant monitoring methodology has been tested for source apportionment of metal deposition around the Cu smelter and former mining town of Karabash. Transplants of the lichen Hypogymnia physodes (L.) Nyl., collected from a 'control' site in July 2001, were set up at 10 stations along a 60 km NE-SW transect centred on Karabash. Samples were collected after 2 and 3 month monitoring periods and analysed using established wet-chemical techniques. The sources of particulate investigated were the smelter blast furnace and converter, floatation tailings, metallurgical slags, local road dusts, top soils and ambient airborne total suspended particulate. From multi-element least-squares modelling the blast furnace was the main source of particulate in transplants close to the smelter (<10 km). Particulate from the converter, with relatively high Pb and Zn, was found to be more widely dispersed, being finer-grained and so having a longer atmospheric residence time. Ambient airborne particulate, sampled in Karabash town using air-pump apparatus, was almost entirely derived from the converter, very different to the lichen transplants from the same area which mainly contained blast furnace particulate. It is proposed that lichens close to the smelter mainly trapped larger blast furnace-derived particulate as they have a low capture efficiency for smaller (converter) particles. The study demonstrates the utility of lichen transplants for monitoring atmospheric deposition and highlights the caution required in their use to assess ambient air quality in human health studies.


Asunto(s)
Cobre/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Líquenes/metabolismo , Minería , Federación de Rusia
4.
Environ Monit Assess ; 98(1-3): 235-59, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15473539

RESUMEN

Airborne total suspended particulates (TSP), dusts from smelter blast furnace and converter stacks, and filtrates of snow melt waters have been characterised in the Cu smelter and former mining town of Karabash, Russia. TSP was collected at sites up- and downwind of the smelter and large waste and tailings dumps (Oct. 2000 and July 2001). Methods for particle size, mineralogical and elemental determinations have been tested and described, and a new PSD-MicroSOURCE XRD technique developed for the mineralogical analysis of microsamples on filter substrates. TSP in downwind samples has a mean equivalent spherical diameter of 0.5 microm (s.d. = 0.2) and was found to be 100% respirable. The main element of human health/environmental concern, above Russian maximum permitted levels (1 microg m(-3), average over any time period), was Pb which was measured at 16-30 microg m(-3) in downwind samples. Individual particulates mainly consisted of complex mixtures of anglesite (PbSO4), Zn2SnO4 and poorly ordered Zn sulphates. From experimental and theoretical considerations, a high proportion of contained Pb, Zn, Cd and As in this material is considered to be in a readily bioavailable form. Chemical and mineralogical differences between the TSP, stack dusts and snow samples are discussed, as well as the implications for human and regional environmental health.


Asunto(s)
Contaminantes Atmosféricos/análisis , Arsénico/análisis , Cobre/análisis , Polvo/análisis , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Contaminantes Atmosféricos/química , Filtración , Metalurgia , Minería , Tamaño de la Partícula , Federación de Rusia , Nieve/química , Difracción de Rayos X
5.
Environ Sci Technol ; 38(24): 6522-8, 2004 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-15669308

RESUMEN

Transplants of the lichen Hypogymnia physodes, which is relatively tolerant to SO2 and heavy metals, were deployed for 3 months over a 60 km long SW-NE transect centered on a highly polluting Cu smelter and its adjoining town of Karabash, southern Urals, Russia. The abundance of 206Pb, 207Pb, 208Pb, and 204Pb were determined by MC-ICP-MS. The measurement of 204Pb revealed critical features, which would otherwise remain concealed: (i) The precise isotope ratios referenced to 204Pb allowed several different sources to be resolved even within the small area covered: (a) the obvious pollutant source of the Karabash Cu smelter; (b) two dispersed sources, likely to include soil with lower and different contributions of thorogenic and uranogenic lead; and (c) one anthropogenic source with higher contribution of 235U derived Pb. (ii) In part of the transect, the Pb isotope composition changed while the Pb concentrations remained the same. This indicates that the Pb content of the transplantation material from the background site was largely replaced and that the transplants provide a transient record reflecting a continuous accumulation and loss of environmental Pb, probably mainly in the form of extracellular particles. Overall, the method of lichen transplantation coupled with Pb isotope ratio determinations proved effective in assessing the usefulness of lichens in biomonitoring and in resolving different sources of atmospheric deposition.


Asunto(s)
Contaminantes Ambientales/análisis , Plomo/análisis , Líquenes/química , Cobre , Monitoreo del Ambiente , Industrias , Isótopos , Metalurgia , Federación de Rusia
6.
Sci Total Environ ; 310(1-3): 179-89, 2003 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-12812742

RESUMEN

SO(2) is no longer the principal factor influencing the vitality and composition of lichen assemblages in London. We provide direct evidence for an impact on lichen growth during episodic high exhaust emissions coupled with unusual climatic conditions. This suggests a combination of particles and nitrogen plays a major role in influencing lichen growth. Nitrogen from traffic emissions may be at least as important as agriculture in influencing the composition of lichen assemblages.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Líquenes , Nitrógeno/efectos adversos , Dióxido de Azufre/efectos adversos , Agricultura , Londres , Dinámica Poblacional , Emisiones de Vehículos
8.
Nucl Med Commun ; 22(10): 1109-17, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11567184

RESUMEN

The status of the homolateral axillary lymph nodes is still the most important prognostic factor in early stage breast cancer. The information obtained from the pathological examination of the lymph nodes guides is of critical importance in the decision process regarding the use of postoperative adjuvant therapy. However, lymph node axillary dissection can be followed by significant locoregional morbidity. The sentinel lymph node (SLN) technique was developed as a means of avoiding the full exploration of the axilla and consists in the identification of the first lymph node in the lymphatic drainage system of the breast tumour in the homolateral axilla. It has been demonstrated that the status of the SLN is highly predictive for the presence or absence of tumour involvement in the remaining lymph nodes in the axilla. In this study we evaluated the SLN technique using both 99mTc labelled dextran 500 and patent blue V dye in relation to the classical lymph node resection a series of 56 women with early breast cancer who attended the Breast Unit of the Academic Hospital of the Federal University of Rio Grande do Sul, Brazil. To our knowledge this is the first report in the literature of the utilization of 99mTc dextran 500 for the SLN technique. As there are no similar commercially available dedicated radiopharmaceuticals labelled for use in lymphoscintigraphy studies, we report on an effective method to label dextran 500 with 99mTc which proved to be simple, inexpensive and yielded similar results for SLN identification compared with those given in the literature. The median age of the patients was 57 years (range 32-82 years). Seventeen patients were age 50 years or less, and 39 patients were older than 50 years. The median tumour size was 2.0 cm (range 0.8-7.0 cm). The mapping of the SLN was possible in all cases during the transoperative period by using a hand-guided gamma probe and a blue dye. A median of 2.0 (range 1-5) SLN were excised per patient. The median of axillary lymph nodes excised per patient was 21 (range 10-36). The calculated sensitivity and specificity of the method were 95.6% and 100%, respectively. The negative predictive value and overall accuracy were 97% and 98.2%, respectively. In conclusion, the SLN technique was feasible and produced similar positive results as previously reported in the literature.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Colorantes , Dextranos , Femenino , Humanos , Persona de Mediana Edad , Compuestos de Organotecnecio , Valor Predictivo de las Pruebas , Estudios Prospectivos , Cintigrafía , Radiofármacos , Colorantes de Rosanilina
9.
Rapid Commun Mass Spectrom ; 14(15): 1332-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10920351

RESUMEN

The numerous stable isotope studies of scleractinian photosynthetic reef-building corals in tropical seas have demonstrated the complexity of the biological and environmental factors that give rise to their isotopic composition. Scleractinian non-photosynthetic corals of the deep cold water environment might be expected to reflect the more stable physical environment in the deep sea. However, in comparison, little is known about their isotope systematics. The present study concentrates on specimens of Lophelia pertusa from the north-eastern Atlantic, the Norwegian Shelf and Fjord. Aliquots taken from the theca represent time series and show variations in delta(13)C and delta(18)O of up to 4.7 and 2.4 per thousand, respectively. The variations seem to be related to morphological features of branching. The tendency of higher values near the tip of the polyps reported previously was detected only in some samples. The delta(18)O of the corals are in all cases more negative than the equilibrium values. There is a strong correlation between delta(13)C and delta(18)O forming linear arrays. The difference between these arrays is more pronounced in delta(13)C. The covariation of delta(13)C and delta(18)O indicates an overruling 'kinetic isotope effect'. This is in line with the behaviour of some trace elements. This isotope effect should be regarded as one manifestation of variations in partition coefficients dictated by a biological control on mineralisation (such as food or reproduction) rather than changes in the relative contribution of metabolic carbon affecting delta(13)C, and changes in temperature affecting delta(18)O.


Asunto(s)
Cnidarios/química , Animales , Océano Atlántico , Isótopos de Carbono , Espectrometría de Masas , Isótopos de Oxígeno , Oligoelementos/análisis
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