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S Mondal

Publications and source records attributed to S Mondal.

66 records · Page 4Linked to original sources

Two-stage chemical oncogenesis in cultures of C3H/10T1/2 cells.

The initiation and promotion stages of chemical oncogenesis have been demonstrated in cultured C3H/10T1/2 mouse embryo cells. Treatment of the cells with a subeffective concentration of 3-methylcholanthrene, benzo(a)pyrene, or 7,12-dimethylbenz(a)anthracene, followed 4 days later by a nontransforming amount of tetradecanoylphorbol acetate (TPA), phorbol didecanoate, or 4-alpha-phorbol didecanoate, produced transformation. Phorbol was ineffective. TPA did not select for transformed cells. When TPA treatment preceded 3-methylcholanthrene, no enhancement of transformation was observed. When TPA was added immediately after hydrocarbon treatment, there was a significant inhibition of transformation. TPA did not exert promoting activity when the hydrocarbons were in high enough concentrations to produce appreciable transformation. The promoting action of TPA cannot be attributed only to a stimulation of cell division.

9,10-Dimethyl-1,2-benzanthracene↗

In vitro malignant transformation by methylcholanthrene of the progeny of single cells derived from C3H mouse prostate.

Cell lines derived from C3H mouse ventral prostate grow to a monolayer, do not pile up, and do not give tumors on inoculation into isologous mice. When treated with carcinogenic hydrocarbons, these cells produce piledup colonies that give rise to fibrosarcomas in mice; these colonies are termed transformed. Individual single cells were treated with 0.5 per cent dimethyl sulfoxide (DMSO), and 2 per cent of them gave rise to clones containing transformed colonies. Under optimal conditions, treatment of individual single cells with 3-methylcholanthrene (MCA) led to the formation of transformed colonies in 100 per cent of the clones. From recloning experiments, it appears probable that all the progeny of the MCA-treated cells were potentially transformed, although the time required for the transformation to be scored was variable. It is concluded that in this system the carcinogen does not select for pre-existing malignant cells.

Animals↗

Co-expression of nestin and vimentin intermediate filaments in invasive human astrocytoma cells.

Intermediate filaments (IFs) are highly diverse intracytoplasmic proteins within the cytoskeleton which exhibit cell type specificity of expression. A growing body of evidence suggests that IFs may be involved as collaborators in complex cellular processes controlling astrocytoma cell morphology, adhesion and proliferation. As the co-expression of different IF subtypes has been linked to enhanced motility and invasion in a number of different cancer subtypes, we undertook the present study to examine the expression of vimentin and nestin in a panel of human astrocytoma cell lines whose tumorigenicity, invasiveness and cytoskeletal protein profiles are well known. Astrocytoma cells were examined for IF protein expression by immunofluorescence confocal and immunoelectron microscopy. The motility of all cell lines was determined by computerized time-lapse videomicroscopy. Invasive potential of astrocytoma cells was determined using Matrigel as a barrier to astrocytoma cell invasion in vitro. Vimentin was expressed by all astrocytoma cell lines. On the other hand, nestin was variably expressed among the different cell lines. The most motile and invasive astrocytoma cell line in our study was antisense GFAP-transfected U251 (asU251) astrocytoma cells which showed marked up-regulation of nestin expression compared to the U251 parental cell line and controls. The U87 astrocytoma cell line also demonstrated high nestin expression levels and was associated with an increased basal motility rate and a high degree of invasiveness through Matrigel. U343 astrocytoma cells did not express nestin, but had high levels of GFAP. It had the lowest motility rate and invasiveness of all the astrocytoma cell lines examined. Taken together, these data suggest that for the astrocytoma cell lines examined in this study, nestin and vimentin co-expression may serve as a marker for an astrocytoma cell type with enhanced motility and invasive potential. Further studies are required to determine the mechanism by which dual-IF protein expression alters other cytoskeletal or cell surface receptor protein components important in the process of astrocytoma invasion.

Astrocytoma↗

Effect of Sahaj Yoga on depressive disorders.

Sahaj Yoga is a meditative technique that has been found to have beneficial effects in some psycho-somatic illnesses. The study was carried out on 30 cases (19 Males, 11 females, age 18-45 years) of major depression diagnosed on the basis of DSM IV criteria. The patients were then randomly divided into two groups: Group 1: (10 Males & 5 Females) Patients who were practising Sahaj Yoga and also received conventional anti-depressants. Group 2: (9 Males & 6 Females) Patients who were only receiving conventional anti-depressants. Training in Sahaj yoga was conducted under the supervision of a trained Sahaj Yogi for 8 weeks. At start of the study, all the patients were subjected to Hamilton Rating Scale for Depression (HAM-D) and Hamilton Rating Scale for Anxiety (HAM-A). Above scales were again assessed after two months of treatment. There was significant improvement in HAM-D as well as HAM-A scores in both Group 1 and Group 2 patients (P<0.001). However, percentage improvement in HAM-D scores and HAM-A scores in patients receiving Sahaj Yoga was significantly higher than in Group 2 patients. The number of patients who went into remission after two months of intervention were also significantly higher in Group 1 patients (P=0.02). The present study demonstrates that Sahaj Yoga has got a potential role as a component in the management of depressive disorders.

Adolescent↗

Implementation of ORT: some problems encountered in training of health workers during an operational research programme.

During an operational research study on implementation of oral rehydration therapy in a block of West Bengal, India, amongst a population of 2, 16,805, a total of 171 Community Health Guides and 152 Anganwadi Workers were initially trained for one working day by lectures and slides about diarrhoea case management at the community level. The training was evaluated after two months and found to be inadequate. The workers were then retrained with modern approach using a module (prepared in local language) as suggested by World Health Organisation. The level of retention of the imparted knowledge of Health Workers for different items 2-3 months after training with lectures and slides ranged between 5-25% except preparation of ORS which was 80%. With the use of modules, 47-98% of health workers could retain the same knowledge 3 months after the training. The knowledge thus acquired were sustained even after 12 months of training to a level which was still much better than that retained 2 months after training with slides and lectures. However some of the items like indication of use of Home Available Fluids, dosage of ORS and when to refer a diarrhoea case to health facility were more difficult to recall after one year. This possibly indicates need for in-service training of grassroot level health workers at suiTable interval.

Community Health Workers↗