Magnetic resonance imaging (MRI) of Saccharum officinarum L. (sugarcane) during its growth for sucrose content.

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.

Solar UV irradiance and some biological consequences: Bombay, India.

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.

Studies on C17 brown mice subjected to photochemotherapeutic doses of long wave length ultraviolet (UVA) radiation.

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.

Trace element profiles in oesophageal neoplasms determined by proton-induced X-ray emission.

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.

Role of 'cell type' in proton relaxation in normal and neoplastic lymph nodes characterized by pulsed NMR spectroscopy.

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.

Alteration of macromolecular events and elemental levels in the skin of UVC exposed hairless mice.

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.

Significance of histopathology in pulsed NMR studies on cancer.

Characterization of tissue by pulsed nuclear magnetic resonance spectrometry opened a new area of research. The differences in the NMR parameters T1 and T2 of normal and malignant tissues constitute the basis for their distinction by pulsed NMR spectrometry and also by NMR imaging in vivo. The present studies were undertaken to correlate the role of constituent histological elements encountered in various malignancy-associated changes and T1 variations and are based on evaluation of samples taken from surgically resected specimens of carcinoma of the esophagus, comprising the uninvolved portions of the esophagus and the gastric end on gross examination. The uninvolved and involved regions showed low and high T1 values, respectively. High T1 values were also encountered in the zones of samples of uninvolved esophagus which histologically revealed areas with dysplasia. This feature, viz., dysplasia representing malignancy-associated changes, has been found to recur in many samples. Detailed histological studies provided further evidence confirming that areas with dysplasia contribute to an increase in T1 values whereas in zones at the gastric end metaplasia and hyperplasia are more common. The results are of value for demarcation of tumor area by in vivo NMR imaging.

Iron, zinc, copper, manganese and magnesium in malignant lymphomas.

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.

Major metals in human cancer: calcium, magnesium, sodium and potassium.

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.

Transition metals in human cancer II.

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.