Technetium-99m-labeled deoxynivalenol from Fusarium mycotoxin alters organ toxicity in BALB/c mice by oral and intravenous route

The toxicity of deoxynivalenol, both intravenously and orally, was investigated in male and female BALB/c mice. Technetium-99m (99m Tc)-labeled deoxynivalenol was administered to mice by tail vein injection and orally dosed. Distribution of labeled deoxynivalenol at 26 hours was monitored by gamma-scintigraphy. In the evaluated organs, the accumulation of radioactive deoxynivalenol was correlated with the amount of radioactivity. In addition, the toxicity of deoxynivalenol was measured by biochemical assays followed by histopathological findings. Kidney and hepatic marker enzymes were significantly increased in intravenously administered deoxynivalenol as compared to orally treated mice. Intravenously treated mice showed severe damage in liver and kidney when compared to those orally exposed. Biodistribution of 99mTc-labeled deoxynivalenol differed between oral and intravenous treatment. In intravenously exposed mice, deoxynivalenol was distributed primarily in the liver and kidney whereas in oral exposure, it was found in the stomach and intestines after 26 hours. Deoxynivalenol toxicity, associated with its biodistribution and organ toxicity, was greatest where it had accumulated. The results show that the toxicity of deoxynivalenol is associated with organ accumulation.(AU)

Reactive oxygen species in health and disease.

With the advent of the use of oxygen as the terminal electron acceptor in aerobic respiration, came the curse in the form of reactive oxygen species (ROS). However, the evolving organism had developed elaborate defence machinery to escape from these reactive byproducts of its own metabolism, and also developed a mechanism for the utilization of these species in physiological processes to gain a survival advantage. ROS have been increasingly implicated in the ageing process and in different diseases such as cancer, Alzheimer's disease, Parkinson's disease, reperfusion injury, etc. They are also important in cellular phenomenon such as signal transduction pathways. We review the mechanisms of production of ROS in the cell, their interaction with cellular macromolecules, pathways of ROS-induced cell death, the mechanisms for protection from ROS-induced damage as well as the key biological and disease processes where ROS play an important role.

Observations on hepatic structure and function in fibro-calculous pancreatic diabetes (FCPD) vis-a-vis other diabetic subtypes.

Investigations of liver function and histology were undertaken in thirty four patients with Fibrocalculous Pancreatic Diabetes (FCPD). The data obtained were compared with those of similarly aged members of a diabetic control group comprising twelve patients with Protein Deficient Diabetes Mellitus (PDDM), twelve with Type 1 diabetes or Insulin Dependent Diabetes Mellitus (IDDM) and four young patients with Type 2 Diabetes of Non-Insulin Dependent Diabetes Mellitus (NIDDM). None of them had apparent past or present liver disease. Elevations of serum ALT (SGPT) and alkaline phosphatase levels were fairly common and was often associated with mild fatty changes and occasionally with focal necrosis and inflammatory changes. Cirrhosis and inflammatory changes per se were infrequent and fatty changes per se did not occur. In contrast patients belonging to the other diabetic subsets were very occasionally afflicted with hepatic abnormalities or not afflicted at all. We propose that loss of hepatotrophic actions mediated by insulin and glucagon could initiate and/or enhance hepatic abnormalities in FCPD where deficiencies of insulin and glucagon coexist.

Isolation and identification of alkaline thermostable lipase producing microorganism and some properties of crude enzyme.

A bacterial strain isolated from soil and identified as Enterococcus faecalis was found capable of producing alkaline thermostable lipase. Optimum pH, temperature and time for enzyme substrate reaction were found to be 8.0, 60 degrees C and 10 min respectively. Phosphates and common surfactants have no or very little inhibitory effects on the activity of the enzyme, whereas bile salts are inhibitory to the enzyme activity. Maximum activity of the enzyme obtained so far is 54.6 IU/ml.

Adaptation of a chemiluminescent DNA detection system to strongly positively charged nylon membranes: single copy gene detection in human genome.

Nonradioactive methods for detection of genes by Southern hybridization are limited to neutral or positively charged membranes which are supplied or explicitly recommended by the manufacturers of the chemiluminescent detection systems. The results of such kits with a known strongly positively charged nylon membrane (Genescreen plus) are disappointing. The adaption of a chemiluminescent detection system to such a strongly positively charged nylon membrane is demonstrated in this communication. The modifications include a blocking step (1% SDS) before prehybridization, use of 5% SDS during hybridization, and 5% SDS and 1% BSA during detection. The increased sensitivity of such a highly positively charged nylon membrane enabled us to detect 2.5 pg of target DNA. The detection of both the alleles of a single copy polymorphic target (YNZ22) in the human genome is also shown.

N-acetyltransferase activity--a susceptibility factor in human bladder carcinogenesis.

A higher proportion of slow acetylator phenotypes has previously been found among bladder cancer patients. In the present study carried out among 77 male bladder cancer patients and 80 non-cancer controls, 59.74% of the patients and 35% of the controls were slow acetylator phenotypes (p < 0.01). The odds of developing bladder cancer was also observed to be significantly higher among smokers than non-smokers (p < 0.01). The findings suggest that slow N-acetyl phenotype is a susceptibility factor in bladder carcinogenesis.

Kwashiorkor and marasmus: changing hospital incidence of syndromic presentation (1957-88).

This clinico-epidemiological study was undertaken to substantiate the impression that the pattern of clinical presentation of protein-energy malnutrition causing kwashiorkor-marasmus syndrome (KMS) is changing over time. An analysis of data for the period 1964-88, obtained from the specialised Pediatric Clinic of the Calcutta School of Tropical Medicine serving mostly the city slums showed decrease (p less than 0.01) in the incidence of chronic edematous forms of severe KMS, less decrease (p less than 0.05) in the incidence of mild-moderate KMS and increase (p less than 0.01) in the incidence of nutritional marasmus and of chronic very severe forms of KMS characterised by extreme retardation in growth and development. Incidentally, a rising incidence of rickets was observed. In the hospitalised cases (1957-88) these observations were corroborated. Data for 1985-88 of NRS Medical College Hospital, Calcutta, a general hospital serving the city as well as the neighbouring rural areas, showed that among the hospitalised city children edematous KMS was proportionately fewer than marasmus. The situation was reverse in the children from the rural areas. The observations suggested that the syndromic presentation of KMS is changing over the last three decades with some rural-urban differences for which only some recent data could be available.