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1.
Magn Reson Imaging ; 1(1): 23-8, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6965035

RESUMEN

Pulsed nuclear magnetic resonance studies have been carried out on bone marrow of normal human subjects and patients with leukemia: chronic myeloid leukemia (CML) and acute myeloid leukemia (AML). It was observed that the proton spin-lattice relaxation time (T1) value was discriminatory in the normal and leukemic cases with a statistical significance of (p less than 0.01). Ouabain treatment of cells did not show any perceptible change of T1 value when compared with the nontreated cells, indicating that the concomitant cation effluxes do not affect spin-lattice relaxation time. The water contents of normal, leukemic, and ouabain treated cells were in the range 60%-80%. Higher Fe levels were encountered in the normal than the leukemic samples, while levels of Zn, Cu, Mn, Co, and Ni were elevated in the leukemic samples compared with the normals. Despite the T1 differences observed, the multiparameter studies do not uniquely pinpoint factors responsible for the elevation of T1 in the malignant state.


Asunto(s)
Médula Ósea/patología , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide/diagnóstico , Espectroscopía de Resonancia Magnética , Médula Ósea/análisis , Médula Ósea/efectos de los fármacos , Humanos , Ouabaína/farmacología
2.
Sci Total Environ ; 40: 245-57, 1984 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6523132

RESUMEN

Many of the trace metals are associated with enzymes involved in vital physiological roles. It would therefore seem reasonable to expect alterations in the levels of certain elements to be associated with cancer. Secondly, their levels would indicate whether or not they have a direct influence on the proton spin-lattice relaxation time (T1), as determined by pulsed nuclear magnetic resonance spectrometry (NMR). The results obtained on leukaemic bone marrow and oesophageal cancer were reported earlier. In the present work is reported the data obtained for the levels of the transition elements Fe, Zn, Mn and Cu in human cancers of other regions of the body. The role of trace metals has been discussed from the point of view both of their value as markers of malignancy, and of the elevation of proton spin-lattice relaxation times.


Asunto(s)
Metales/metabolismo , Neoplasias/metabolismo , Cobre/metabolismo , Femenino , Humanos , Hierro/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Manganeso/metabolismo , Especificidad de Órganos , Zinc/metabolismo
3.
Sci Total Environ ; 41(1): 79-89, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3969548

RESUMEN

Major elements calcium, magnesium, sodium and potassium in normal and neoplastic tissues were determined by atomic absorption spectrophotometry. Samples of neoplastic tissues were taken from surgically resected materials from different regions; oral, respiratory, gastro-intestinal, breast, reproductive regions and bone marrow and diverse types of neoplasms. Samples from areas which, on gross examination, looked normal were designated as uninvolved and were also analysed together with controls from normal Indian subjects. In neoplastic tissues concentrations of magnesium, sodium and potassium were found to be enhanced, while variability was noted for the distribution of calcium in the normal and malignant state.


Asunto(s)
Calcio/análisis , Magnesio/análisis , Neoplasias/análisis , Potasio/análisis , Sodio/análisis , Calcio/metabolismo , Femenino , Humanos , Magnesio/metabolismo , Masculino , Neoplasias/metabolismo , Potasio/metabolismo , Sodio/metabolismo , Espectrofotometría Atómica , Distribución Tisular
4.
Sci Total Environ ; 42(3): 237-43, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-4001919

RESUMEN

Lymph node and spleen tissues involved in malignant lymphomas were analysed for iron, manganese, copper, zinc and magnesium by atomic absorption spectrophotometry. The levels of iron are found to be significantly lower in the case of Hodgkin's lymphoma compared with non-Hodgkin's lymphoma and normal lymph nodes. However, they are elevated in Hodgkin's lymphoma when compared with the normal value for spleen tissues. Magnesium is significantly higher in lymph nodes of non-Hodgkin's lymphoma compared with Hodgkin's lymphoma and normal values, but is not altered significantly in spleen tissues. The distribution of the other elements examined is not altered significantly in malignant lymphomas. The importance of the in situ levels of these elements to NMR imaging is discussed.


Asunto(s)
Linfoma/análisis , Oligoelementos/análisis , Cobre/análisis , Humanos , Hierro/análisis , Ganglios Linfáticos/análisis , Magnesio/análisis , Manganeso/análisis , Bazo/análisis , Zinc/análisis
5.
Sci Total Environ ; 121: 195-201, 1992 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-1439726

RESUMEN

Measurements of solar UV radiation (UVR) at Bombay, India, lattitude 18.5 North and longitude 72.5 East were recorded using Eppley UV radiometer for a 2-year period. The UV irradiance is calculated and presented. The annual and diurual trends in the quantitation of UVR are examined. The consequences of solar UVR and its projected increase are discussed with special reference to its biological effects and results of UVR on experimental animal systems vis a vis and epidemiological data in the Indian context.


Asunto(s)
Neoplasias Inducidas por Radiación/etiología , Neoplasias Cutáneas/etiología , Luz Solar , Rayos Ultravioleta , Animales , Bovinos , Enfermedades de los Bovinos , Ritmo Circadiano , Humanos , India , Neoplasias Inducidas por Radiación/epidemiología , Neoplasias Inducidas por Radiación/veterinaria , Factores de Riesgo , Estaciones del Año , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/veterinaria , Tiempo
6.
Sci Total Environ ; 78: 167-72, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2717919

RESUMEN

Trace element concentrations were determined in surgically resected, cancerous human oesophageal tissue by proton-induced X-ray emission (PIXE) analysis. Each sample was divided into six zones, E3 and E4 formed the central tumour region, E1 and E2 were proximal to the oesophagus and E5 and E6 distal to the oesophagus. Malignancy was confirmed histopathologically in all cases. Samples were dissolved in NaOH solution and pipetted onto a thin mylar film for analysis by a proton beam from a Van de Graaff accelerator. Titanium, Fe, Cu, Zn, As, Rb, Br and Pb were detected in varying concentrations. Of these, Ti, Fe, Cu, Zn and As showed specific behaviour in the six zones.


Asunto(s)
Neoplasias Esofágicas/análisis , Oligoelementos/análisis , Carcinoma/análisis , Carcinoma/cirugía , Neoplasias Esofágicas/cirugía , Humanos , Espectrometría por Rayos X/métodos
7.
Tumori ; 65(2): 157-62, 1979 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-462567

RESUMEN

The pulsed nuclear magnetic resonance technique was explored for its potential diagnostic value in human cancer. Measurements of proton spin-lattice relaxation times (T1) of cellular water protons of normal and malignant esophageal tissues showed elevated T1 values in the latter. In some cases, tissues which appeared normal on gross examination assumed as uninvolved tissues had T1 values higher than the other grossly uninvolved tissues and often closer to the T1 of the corresponding tumor tissue. A histopathological study of the assumed uninvolved areas also studied for the T1 values was therefore undertaken. A preliminary study demonstrated the presence of malignant cell groups or clusters in some of the uninvolved samples with higher T1 compared to the true uninvolved tissues, which had a normal histological picture and low T1 values. This observation has brought out the importance of histopathological studies in addition to relaxation studies to comprehend contributory factors to relaxation. Secondly, it lends support to the thesis of elevated T1 values being characteristics of the malignant state.


Asunto(s)
Neoplasias Esofágicas/diagnóstico , Espectroscopía de Resonancia Magnética/métodos , Biopsia , Neoplasias Esofágicas/patología , Humanos , Técnicas In Vitro
8.
Indian J Exp Biol ; 38(10): 1062-5, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11324162

RESUMEN

Magnetic Resonance Imaging (MRI) was employed to monitor changes in image intensities in stems of sugarcane which reflect on the increase in sucrose concentration. Contrast in images originates in the increase of sucrose concentration in the aqueous phase of the predominant parenchyma cells and physiological changes. In matured stems mixed MR intensity patterns were observed in transverse planes. We associate this due to the reflection of vascular bundles in ground parenchyma cells which constitute 80% sucrose storage.


Asunto(s)
Poaceae/química , Sacarosa/análisis , Imagen por Resonancia Magnética , Poaceae/crecimiento & desarrollo
9.
Physiol Chem Phys Med NMR ; 18(3): 197-205, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3588697

RESUMEN

Swiss mice (S/RV/Cri-ba) were exposed to a spectral range of UV light emitting predominantly lambda 253.7 nm. Following a cumulative dose of 22.5 X 10(3) KJ/m2 tumours were induced. The tumour development occurred after 52 weeks, relatively a longer time interval following exposure, compared with shorter time intervals required for production of tumours in mice by spectral range UVA and UVB as observed by other workers. A study of biochemical events viz. levels of protein, DNA, zinc, iron, sodium and potassium has been made in the skin samples of control and irradiated animals following ultraviolet irradiation with a dose of 22.5 X 10(3) KJ/m2. Study of macromolecular events in the skin of control and irradiated mice, showed fluctuations in the levels of DNA. A particularly notable event is the occurrence of increased levels of DNA and zinc and their persistence during the 9-39 weeks post UV interval prior to tumour production. No such variation was observed in the control group in any of the intervals. Increased levels were also seen in case of iron, sodium and potassium at different intervals in the post UV periods. These fluctuations in various biochemical events are deemed to be indicative of UV initiated biochemical changes.


Asunto(s)
Piel/efectos de la radiación , Rayos Ultravioleta , Animales , ADN/biosíntesis , Elementos Químicos/análisis , Hierro/metabolismo , Ratones , Ratones Pelados , Potasio/metabolismo , Biosíntesis de Proteínas , Piel/metabolismo , Sodio/metabolismo , Zinc/metabolismo
10.
Physiol Chem Phys Med NMR ; 20(1): 79-86, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3406142

RESUMEN

Pulsed NMR studies have been undertaken on malignant lymphomas. It has been observed that water proton spin-lattice relaxation times of lymph node tissues show increase in lymphnodes of Hodgkin's and Non-Hodgkin's lymphoma as compared to those in normal subjects. The T1 values of normal lymphnodes showed a range of 200-300 msec, while the metastatic lymphnodes showed a range of 400-600 msec at 20 MHz. These studies have brought out the importance of histopathological significance and the role of 'cell type' and biomolecules as a factor influencing water proton relaxation times. Further the relevance of the present in vitro studies to Magnetic Resonance Imaging of ex vivo images of normal and metastatic lymphnodes has become evident from some recent studies reported in normal and afflicted lymphnodes.


Asunto(s)
Ganglios Linfáticos/patología , Linfoma no Hodgkin/patología , Linfoma/patología , Adenocarcinoma/patología , Humanos , Ganglios Linfáticos/citología , Metástasis Linfática , Espectroscopía de Resonancia Magnética/métodos , Valores de Referencia
11.
Physiol Chem Phys Med NMR ; 22(2): 73-80, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2100007

RESUMEN

In this study the risk of photochemotherapeutic dose levels of long wave ultraviolet radiation (UVA) was assessed by employing a laboratory animal system, C17 brown mice. The experimental group was subjected to three UVA dose levels, 1000, 2000 and 3500 J/cm2. The dose regimen 50 J/cm2 per day for five days a week was completed in 4, 8 and 14 weeks respectively. The UVA exposed animals were examined until 52 weeks post UVA exposure periods for morphological lesions. Estimations of DNA, protein levels and dermal, epidermal thickness were made. There were no lesions observed with the highest UVA dose employed. Alterations in the DNA and protein levels in the skin of animals in the exposed groups were observed in the post UVA periods. A notable increase in the DNA level was observed 47 weeks post UVA period. The significance of alterations in DNA and protein levels needs to be studied further for evaluation of long term risk following UVA exposure. The data presented however led to a conclusion that the photochemotherapeutic doses of UVA do not pose any risk of cancer to pigmented mouse strains.


Asunto(s)
Piel/efectos de la radiación , Rayos Ultravioleta , Animales , ADN/análisis , ADN/efectos de los fármacos , ADN/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Femenino , Metoxaleno/farmacología , Ratones , Ratones Endogámicos , Fotoquimioterapia , Proteínas/análisis , Proteínas/efectos de la radiación , Valores de Referencia , Piel/citología , Piel/efectos de los fármacos , Factores de Tiempo
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