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S Ganesh

Publications and source records attributed to S Ganesh.

51 records · Page 3Linked to original sources
PubMed1994

Transdermal nicotine for active ulcerative colitis.

BACKGROUND: Ulcerative colitis is largely a disease of nonsmokers. Because anecdotal reports suggest that smoking and nicotine may improve the symptoms of the disease, we examined the effect of nicotine as a supplemental treatment for ulcerative colitis. METHODS: We treated 72 patients with active ulcerative colitis with either transdermal nicotine patches or placebo patches for six weeks in a randomized, double-blind study. Incremental doses of nicotine were given; most patients tolerated doses of 15 to 25 mg per 24 hours. All the patients had been taking mesalamine, and 12 were receiving low doses of glucocorticoids; these medications were continued without change during the study. Clinical, sigmoidoscopic, and histologic assessments were made at base line and at the end of the study; symptoms were recorded daily on a diary card, and the clinician made a global assessment. Side effects and plasma nicotine and cotinine concentrations were monitored throughout the study. RESULTS: Seventeen of the 35 patients in the nicotine group had complete remissions, as compared with 9 of the 37 patients in the placebo group (P = 0.03). The patients in the nicotine group had greater improvement in the global clinical grade of colitis (P < 0.001) and the histologic grade (P = 0.03), lower stool frequency (a difference of 1.6 stools daily; P = 0.008), less abdominal pain (P = 0.05), and less fecal urgency (P = 0.009). More patients in the nicotine group had side effects (23, vs. 11 in the placebo group; P = 0.002), the most common of which were nausea, lightheadedness, headache, and sleep disturbance. Withdrawals due to ineffective therapy were more common in the placebo group (3 vs. 8, P = 0.12). CONCLUSIONS: The addition of transdermal nicotine to conventional maintenance therapy improves symptoms in patients with ulcerative colitis.

Administration, Cutaneous↗
PubMed1994

Inactive urokinase and increased levels of its inhibitor type 1 in colorectal cancer liver metastasis.

BACKGROUND/AIMS: Human colorectal carcinogenesis was previously found to be associated with an increased urokinase-type plasminogen activator expression, both in antigen and activity, accompanied by simultaneously enhanced levels of plasminogen activator inhibitors type 1 and type 2. This increased proteolytic activity may contribute to invasive growth and metastasis of the tumors. METHODS: In the present study, homogenates of liver metastases, primary colorectal carcinomas, and adjacent normal tissues were evaluated regarding the level and composition of urokinase, tissue-type plasminogen activator, and plasminogen activator inhibitors. RESULTS: Concentrations of urokinase were significantly increased in primary carcinomas and liver metastases compared with normal tissues, whereas tissue-type plasminogen activator levels were significantly decreased. Liver metastases showed, in contrast to the carcinomas, hardly any activity of plasminogen activators, which could be attributed to the enhanced presence of the inactive proenzyme form of urokinase in combination with more complexes of plasminogen activators with inhibitors. Furthermore, liver metastases had an eightfold higher content of inhibitor type 1 compared with the primary carcinomas. The excess of inhibitors was confirmed by addition of plasminogen activators to metastasis homogenates, which resulted in increased complex formation. CONCLUSIONS: Colorectal cancer metastasis in the liver is associated with an inactivation of the enhanced urokinase cascade, which might allow tumor cells to settle in the liver.

Colorectal Neoplasms↗
PubMed1994

Tetranectin expression in human colonic neoplasia.

The expression of tetranectin in colonic neoplasia was evaluated by determining the tissue distribution by immunohistological analysis of tissue sections and the antigen levels in tissue homogenates and plasma. In normal colonic mucosa tetranectin staining was predominantly found in the goblet cells whereas in adenocarcinomas this staining was confined to the tumour stroma. Colonic adenomas, benign precursors of adenocarcinomas, showed fewer tetranectin positive goblet cells and in some cases showed tetranectin expression in the stroma. Within the tissue homogenates no differences were found in the tetranectin levels between normal mucosa, adenomas and carcinomas. Patients with colonic cancer were found to have significantly decreased plasma tetranectin levels compared to healthy controls. Thus, colonic neoplasia is associated with a change in the tissue distribution of tetranectin, without an obvious change in the tissue level, and a low plasma tetranectin level.

Adenocarcinoma↗
PubMed1993

Plasminogen activators in normal tissue and carcinomas of the human oesophagus and stomach.

Carcinogenesis in the human colon is associated with a marked increase of urokinase type plasminogen activator and a decrease of tissue type plasminogen activator. This study was performed to determine the concentrations of urokinase type plasminogen activator and tissue type plasminogen activator in normal tissue and carcinomas along the upper part of the gastrointestinal tract. Activity and antigen levels of both activators were determined in homogenates of endoscopically obtained biopsies from normal and carcinomatous tissues. Although the concentrations of tissue type plasminogen activator and urokinase type plasminogen activator in normal squamous epithelium of the oesophagus were low compared with those in columnar epithelium from the stomach, the urokinase type plasminogen activator/tissue type plasminogen activator antigen ratio of the different locations showed hardly any difference. Significant but heterogeneous increases were found in urokinase type plasminogen activator concentrations of biopsy specimens originating from carcinomas of both epithelial cell types. A decrease in tissue type plasminogen activator concentrations, as found in human colon carcinomas, could only be shown in carcinomas of columnar epithelium origin but not in squamous cell carcinomas of the oesophagus. The increase of urokinase type plasminogen activator and urokinase type plasminogen activator/tissue type plasminogen activator antigen ratio and the decrease of tissue type plasminogen activator in the carcinomas did not show a significant correlation with known prognostic determinants as differentiation grade, TNM classification, intestinal metaplasia, inflammation, and ulceration. The heterogeneous increase of urokinase type plasminogen activator in oesophageal and stomach carcinomas, together with the recently described association of urokinase type plasminogen activator in tissue extracts of breast carcinomas with aggressiveness and prognosis, may be relevance to prognostic studies, may be of relevance to prognostic studies in oesophageal and gastric cancer.

Duodenum↗
PubMed1993

Comparison of bismuth citrate and 5-aminosalicylic acid enemas in distal ulcerative colitis: a controlled trial.

An enema that contained a complex of bismuth citrate and polyacrylate was compared with 5-aminosalicylic acid (5-ASA) enemas for treatment of distal ulcerative colitis. The multicentre trial involving 63 patients was randomised and double blind with enemas given over four weeks; clinical, sigmoidoscopic, and histological assessments were made. Improvements were seen in both treatment groups. Clinical remission was seen in 18 of 32 patients treated with 5-ASA and 12 of 31 patients treated with bismuth citrate-carbomer (chi 2 1.94; p = 0.16). Sigmoidoscopic remission occurred in 20 of 32 patients in the 5-ASA group and 15 of 31 patients given bismuth (chi 2 1.27; p = 0.26). Improvement of rectal biopsy histology by at least one grade was seen in 16 of 32 patients in the 5-ASA group and 14 of 31 patients with bismuth (chi 2 0.15; p = 0.70). Analysis of covariance gave no significant difference between groups, although there was a trend favouring 5-ASA. There was no evidence of bismuth accumulation during the trial. Bismuth enemas may offer a new therapeutic option in distal ulcerative colitis.

Adult↗
PubMed1993

Increased urokinase receptor levels in human gastrointestinal neoplasia and related liver metastases.

Human carcinomas of the oesophagus, stomach, colorectum, and their liver metastases were previously shown to have increased levels of the urokinase-type plasminogen activator (u-PA). The proteolytic activity of u-PA on the surface of tumour cells is thought to play a key role in invasion and metastasis of malignancies. Therefore, in this study we quantitatively determined the presence of specific u-PA receptors in human gastrointestinal carcinomas, premalignant colonic adenomas, liver metastases, and adjacent normal tissues. All carcinomas showed a 2- to 13-fold higher level of u-PA receptor than their corresponding normal tissues at both the antigen level (ELISA) and the mRNA level (Northern blotting). Colonic adenomas also showed enhanced levels of the u-PA receptor protein. The state of occupancy of the u-PA receptors was determined using a specific ligand-binding assay in which free u-PA receptors were cross-linked with 125I-u-PA and visualized by autoradiography. Colonic carcinomas and liver metastases contained higher levels of free u-PA receptor compared to their corresponding normal tissues. Acid treatment of the receptors prior to cross-linking did not enhance the u-PA/u-PA receptor complex formation. The free u-PA receptor levels in colonic adenomas and in oesophageal and stomach carcinomas showed less difference compared with their normal reference tissues. The increased presence of specific receptors for u-PA in gastrointestinal carcinomas, particularly primary colonic carcinomas and their metastatic lesions in the liver, emphasizes the involvement of the urokinase pathway of plasminogen activation in gastrointestinal carcinogenesis and renders it a putative target for clinical intervention.

Carcinoma↗
PubMed1992

Does smoking influence the pharmacokinetics and pharmacodynamics of the H2-receptor antagonist famotidine?

Twelve healthy habitual cigarette smokers and eight non-smokers participated in a double-blind placebo controlled study to determine the effect of smoking on the pharmacokinetics and pharmacodynamics of the H2-receptor antagonist famotidine. In smokers, cigarette smoking was standardised and started 1 h before (A), or 2 h after (B) drug administration, or was prohibited (C). Intragastric pH-levels (IGpH) were measured with an ambulatory pH-recorder. Famotidine (40 mg orally) significantly raised median 22 h IGpH in non-smokers and smokers in all study periods. The smoking sequence (A, B, C) did not significantly influence median 22 h IGpH in both placebo-treated and famotidine-treated smokers, and no significant difference in median 22 h IGpH was shown between smokers and non-smokers. Plasma drug concentrations were similar in the various experiments, although famotidine was detected earlier in plasma from non-smokers compared with smokers (P less than 0.05). Smoking did not interfere significantly with the pharmacokinetics and pharmacodynamics of famotidine.

Adult↗
PubMed1992

[Growth-inhibiting effect of colchicine on cultured vascular wall myocytes from arteriosclerotic lesions].

Proliferative, migratory, and secretory activities of vascular smooth muscle cells are currently discussed as determinants of human plaque and restenosis formation. Affecting these determinants with drugs may promise anti-arteriosclerotic effects. Plaque tissue was removed from both coronary and peripheral lesions of a total of 18 patients to cultivate smooth muscle cells (SMC) for subsequent in vitro studies. The antitubulin colchicine (C) caused a concentration-dependent decrease of SMC proliferative activity with an IC50 of 5 x 10(-9) M. Migratory activity was analyzed by a standardized semi-automatic video system. This parameter was reduced by C in a concentration-dependent manner (IC50: 5 x 10(-10) M). As shown by immunofluorescence microscopy, the typical structure of microtubules of C-treated SMCs was distorted, whereas the pattern of alpha-actin filaments remained unaltered. Transmission electron microscopy (TEM) revealed that the number of microtubules was diminished after addition of C, and that a distinct disorganization of cytoplasmic organelles as well as the formation of vacuoles had occurred. In vitro studies of human smooth muscle cells derived from vascular plaques indicate that colchicine may be useful as an anti-arteriosclerotic drug, since a concentration-dependent concordant effect on proliferation, migration, and secretory processes of the SMC could be demonstrated.

Aged↗
PubMed1991

[The migration behavior of human vascular myocytes in culture--the screening potential of anti-arteriosclerosis active endogenous and exogenous substances].

Besides proliferation, migration of smooth muscle cells (SMC) is considered to be an essential cellular mechanism involved in plaque formation. Human SMCs were cultured from 14 arteriosclerotic lesions of coronary (n = 5), femoral (n = 7) and aortic (n = 2) arteries. By a semi-automatic standardized video analysis system SMC migratory activity was quantified to be 21.7 +/- 2.1 microns/h (n = 14; x +/- SD). Addition of drugs, such as calcium antagonists (10(-5) - 10(-7) M), heparin (100 micrograms/ml), SIN-1 (10(-5) M) and colchicine (10(-7) M) resulted in a significant decrease of SMC migratory velocity. Exposure to endogenous extracellular matrix proteins (5 micrograms/cm2) showed no effect for collagen I and a significant reduction of SMC migratory activity for fibronectin, respectively. Our results indicate SMC migratory velocity to be a parameter of potential interest to screen various substances for an anti-arteriosclerotic effect.

Arteriosclerosis↗
PubMed1989

Akathisia in neuroleptic medicated mentally handicapped subjects.

Sixty-six neuroleptic medicated mentally handicapped subjects in a hospital were studied to determine the prevalence of drug-induced akathisia. Tardive dyskinesia was also rated on the AIMS scale. Only motor manifestations of akathisia could be assessed as the subjective component of akathisia was difficult to elicit in this population with difficulties in verbal communication. As all the subjects had been on neuroleptics for at least 3 years, only chronic akathisia could be studied. Five subjects had akathisia. Correlational analysis did not reveal any specific associations with any of the demographic, clinical and pharmacological variables studied. A step-wise multiple regression analysis indicated that younger age could be a predictor. Tardive dyskinesia was associated in two of the subjects. The overall conclusion was that 7% of the subjects had chronic akathisia and no specific risk factors could be identified.

Adult↗
PubMedDate not supplied

Hypoglycemic hemiplegia in an adolescent with insulin-dependent diabetes mellitus: a case report and a review of the literature.

A case of hypoglycemic hemiparesis in a fifteen-year-old girl with insulin dependent diabetes mellitus (IDDM) is described. The initial presentation included left facial paresis and muscular weakness of the left upper and lower extremities, associated with a blood glucose level of 31 mg/dL. The patient recovered completely after a glucose infusion. Her neurological examination became normal within 24 hours and remained so for a follow-up period of 6 months. Hypoglycemic hemiparesis is rarely described in children and adolescents.

Adolescent↗
PubMedDate not supplied

Prognostic value of plasminogen activators and their inhibitors in colorectal cancer.

Colorectal tumorigenesis is associated with remarkable changes in the plasminogen activation system at the tissue level. The sequence of normal mucosa-adenomatous polyp-adenocarcinoma-metastasis is accompanied by an increase in the urokinase-type of plasminogen activator, the urokinase receptor and the inhibitors type-1 and type-2, with a concurrent decrease in the tissue-type plasminogen activator. Overall survival analysis of colorectal cancer patients, with a follow-up of more than 5 years, revealed that several of these components, in both the carcinomas and their corresponding normal mucosa, are of prognostic value independent of major clinicopathological parameters. Therefore, the plasminogen activation cascade not only contributes to the invasive and metastatic growth of colorectal tumours, but might also have a clinical impact with respect to adjuvant and intervention therapy.

Biomarkers, Tumor↗
PubMedDate not supplied

[Juvenile myoclonic epilepsy in chromosome 6p12: clinical and genetic advances].

Amongst idiopathic generalized epilepsies, juvenile myoclonic epilepsy (JME) is the most common, accounting for 12% to 30% of all epilepsies in the Western world. Classic JME consists of awakening myoclonias, grand mal convulsions and EEG 4 to 6 Hz polyspike waves that appear in adolescence. Probands and affected family members do not have pyknoleptic 3Hz spike and wave absences. However, in 10 to 30% of patients, rare or spanioleptic polyspike wave absences appear. In 1988,1995,1996,we mapped classic JME to a 7 cM locus in chromosome 6p12 11, called EJM1, using families from Los Angeles and Belize. In 2001,we studied one large family from Belize and 21 new families from Los Angeles and Mexico Cities, aided by a BAC/PAC based physical map and 6 new dinucleotide repeats, to narrow EJM1 to an interval between D6S272 and D6S1573. In 2002, we found myoclonin, the putative gene for typical JME in 6p12. At the congress, we will reveal the identity of the myoclonin gene, its putative function and discuss the significance of this discovery in the JME population at large.

Belize↗
PubMedDate not supplied

Drug delivery to the central nervous system: a review.

The brain is a delicate organ, and evolution built very efficient ways to protect it. Unfortunately, the same mechanisms that protect it against intrusive chemicals can also frustrate therapeutic interventions. Many existing pharmaceuticals are rendered ineffective in the treatment of cerebral diseases due to our inability to effectively deliver and sustain them within the brain. General methods that can enhance drug delivery to the brain are, therefore, of great interest. Despite aggressive research, patients suffering from fatal and/or debilitating central nervous system (CNS) diseases, such as brain tumors, HIV encephalopathy, epilepsy, cerebrovascular diseases and neurodegenerative disorders, far outnumber those dying of all types of systemic cancer or heart disease. The clinical failure of much potentially effective therapeutics is often not due to a lack of drug potency but rather to shortcomings in the method by which the drug is delivered. Treating CNS diseases is particularly challenging because a variety of formidable obstacles often impede drug delivery to the brain and spinal cord. By localizing drugs at their desired site of action one can reduce toxicity and increase treatment efficiency. In response to the insufficiency in conventional delivery mechanisms, aggressive research efforts have recently focused on the development of new strategies to more effectively deliver drug molecules to the CNS. This review intends to detail the recent advances in the field of brain-targeting, rational drug design approach and drug delivery to CNS. To illustrate the complexity of the problems that have to be overcome for successful brain targeting, a brief intercellular characterization of the blood-brain barrier (BBB) is also included.

Biological Transport↗