Differential transcriptional expression following thidiazuron-induced callus differentiation developmental shifts in rice.

Very little is known about molecular events associated with callus differentiation in indica rice. The genes expressed differentially during shoot meristem initiation were identified on genomic arrays applied to efficiently regenerating rice calli. A thidiazuron (TDZ; N-phenyl-N-thiadiazol-1,2,3-5,ylurea)-dependent regeneration protocol was developed for efficient embryogenesis in indica rice. The regenerating embryogenic calli induced by TDZ for 10 days showed transcriptional modulation of a number of genes associated with photosynthesis, hormone metabolism, plant development, signal transduction, light response, and plant defense. Eighteen candidate miRNAs were predicted to target the genes expressed differentially in the embryogenic calli grown in TDZ-containing medium. The majority of the photosynthesis-related genes up-regulated in differentiating calli were not expressed or were down-regulated in developing seeds and inflorescences. Most of the genes down-regulated in differentiating calli were up-regulated in developing seeds. The transcriptome of differentiating callus most closely resembled that of the germinating whole seed.

Anticonvulsant and neurotoxicity evaluation of some 6-substituted benzothiazolyl-2-thiosemicarbazones.

Various 6-substituted benzothiazolyl-2-thiosemicarbazones were synthesized and screened for anticonvulsant activity in maximal electroshock induced seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) induced seizure models in mice. The neurotoxicity was assessed using the rotorod method. The 6-methyl benzothiazolyl-2-thiosemicarbazones showed anticonvulsant activity in both mice i.p. and rat oral MES screen. The 6-nitro benzothiazolyl thiosemicarbazone derivative 1a emerged as the most promising one with anti-MES activity in mice i.p., rat i.p. and rat p.o. evaluations. All the compounds exhibited lesser or no neurotoxicity compared to phenytoin. The isatinimino derivatives had shown better activity when compared to the benzylidene or acetophenone derivatives.

Diagnosis of microfilaria in gastric brush cytology. A case report.

BACKGROUND: Filariasis due to Wuchereria bancrofti is endemic to southern Asia. While the laboratory diagnosis has been conventionally made by demonstrating microfilariae in peripheral blood smears, these have also been occasionally diagnosed on aspiration cytology of various organs. CASE: A 54-year-old male presented with a burning sensation in the epigastrium of five months' duration. Endoscopic brush biopsy revealed numerous sheathed microfilariae of W bancrofti. The patient had had no symptoms suggestive of filarial infection in the past. Cytology revealed numerous microfilariae among lymphocytes and neutrophils. CONCLUSION: This case illustrates that a thorough examination of gastric brushings can at times reveal unexpected findings and may prove to be a useful supplement to endoscopic biopsy.

Glutathione depletion and oxidative damage in mitochondria following exposure to cadmium in rat liver and kidney.

The dose-dependent effects of cadmium (Cd) on mitochondria and post-mitochondrial supernatant (PMS) of liver and kidney were investigated in adult male albino rats. Two groups of rats were injected intraperitoneally with 0.1 mg Cd/kg body weight and 1 mg/kg body weight, respectively, for a period of 3 months (5 days/week). This resulted in a significant decrease in total glutathione (GSH) levels, irrespective of the doses, in mitochondrial as well as in PMS fractions of liver and kidney. In contrast, end products of lipid and protein were significantly increased in a dose-dependent manner in subcellular fractions of liver and kidney. These results suggest that the depletion of tissue glutathione levels is not a primary reason of the observed oxidative damage in liver and kidney caused by Cd.

Profile of reactive oxygen species generation and antioxidative mechanisms in the maturing rat kidney.

The antioxidative potential and reactive oxygen species generation were assessed in rat kidney during early critical periods of development and maturation. Superoxide anion generation was found to be low in kidney during early postnatal days of development, whereas hydrogen peroxide levels remained unaltered during development. The levels of thiobarbituric acid reactive substances and protein carbonyls in developing kidney were higher during early postnatal days, up to 26 days after birth, compared to the adult levels. Kidney sulphydryl contents were significantly less during early periods (9 days postnatally) of development compared to adults but attain adult value by postnatal day 26. The levels of ascorbic acid and ceruloplasmin were also higher in developing kidney than in adults. Among enzymic antioxidants, the levels of glutathione peroxidase (GPx) enzyme in developing kidney were high during the early developmental period of the study as compared to adults; however, superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) were found to be significantly low at early postnatal days up to 16 days of age, which subsequently attained maturational level by the age of 26 days. The levels of antioxidant enzymes and sulphydryl contents in the developing kidney during early periods after birth are low but they increase subsequently with increasing age. Therefore, the present finding suggests that immature kidneys are in a highly dynamic stage of development during the early period and are equipped with antioxidative defence mechanisms that may have a predominant role in protecting against oxidative challenge.

Effect of pyrethroid-based liquid mosquito repellent inhalation on the blood-brain barrier function and oxidative damage in selected organs of developing rats.

Pesticides have been implicated in various neurological disorders in humans and experimental animals. Our earlier studies have demonstrated a high vulnerability of developing blood-brain barrier (BBB) towards very low level exposure of quinalphos, cypermethrin and lindane. Earlier it has been observed that a cypermethrin-induced increase in the BBB permeability of neonatal rats was found to be persistent, requiring a longer period of withdrawal for complete recovery. These observations lead us to investigate the effect of a commonly available liquid mosquito repellent (MR) containing a pyrethroid compound, allethrin (3.6% w/v), on the functional integrity of the developing BBB and on certain parameters of oxidative damage in brain, liver and kidney. Two-day-old rat pups were allowed to inhale the MR (18 h per day) for 8 days (postnatal days (PND) 2-9). Rats exposed to MR were further withdrawn from the exposure for 8 days (PND 10-17) to study whether the changes induced following inhalation are reversible. Results of the study have shown a significant increase in the BBB permeability (45%) of the MR-exposed rat pups to a micromolecular tracer, sodium fluorescein (mol. wt. 376), used for the quantitative assessment of the BBB permeability, suggesting a delayed maturity of the BBB system. Brain glutathione (GSH) levels were also decreased (17%) in the exposed individuals. The oxidatively damaged end-products of lipids, measured as lipid hydroperoxides and conjugated dienes, were found to be increased in brain (42%, 16%), liver (34%, 20%) and kidney (68%, 29%), respectively. The oxidative product of protein, measured as protein carbonyls, was also increased significantly in liver (43%) and kidney (16%) of the MR-exposed rat pups as compared to age-matched controls. The biochemical changes that occurred in the BBB permeability and the oxidatively damaged end-products following MR inhalation in neonatal rats were, however, found to be completely recovered except for an increase in brain GSH (28%) level. The results suggest the possibility of health risk due to exposure to pesticide-based mosquito repellents, especially when exposure takes place in individuals at an early age.

A community-based study on the effect of hexachlorocyclo-hexane (HCH) exposure in spraymen and general population.

The study was carried out in Allahabad district, (Uttar Pradesh) with 260 spraymen as test subjects and 50 persons as controls from a sprayed and unsprayed village respectively. Majority of the spraymen (44%) had worked for 3-4 years (seasons) and 31% had worked in the programme for 5-10 years. The spraymen were relatively healthy with no complaints in 77% whereas the figures were 76% for the Community living in the sprayed village, and 50% for the Community in the unsprayed village. A comparison of the biochemical parameters revealed lowered Cholesterol more than 150 mg % in 38% of the spraymen and 58% had altered A:G ratio. Other biochemical estimations were not significantly different from the control population. The mean residue of Alpha, Beta and Gamma Isomers and the total Alpha, Beta and Gamma isomers were 0.0317, 0.2254, 0.0288 and 0.2859 mg/1 respectively; the corresponding mean values in the control population were 0.0211, 0.1112, 0.0197 and 0.1520 mg/1 respectively. The values in spraymen were twice those of the general population. A significant association (p < .05) was observed between their length of exposure and the levels of Cholesterol and HCH isomers in blood of spraymen. No significant morbidity was evident in spraymen due to HCH exposure.

Proximal versus distal carcinoma of the stomach. A clinicoendoscopic study.

During the period 1978 to 1988, 4619 upper gastrointestinal fibreoptic panendoscopies were carried out. There were 106 (2.2%) histologically confirmed cases of carcinoma of the stomach. The annual incidence was 9.6. The peak incidence was in the fifth decade. The mean age of these patients was 49.4 years and the male: female ratio was 3.6:1. The most frequent symptoms were weight loss (81%) and anorexia (72.9%). Dysphagia was present in 30% of patients. Thirty two percent of patients had proximal carcinoma, 63.2% had distal carcinoma and in 4.7% the whole stomach was involved. Patients with distal carcinoma had a longer history (P less than 0.01) and were more likely to present with weight loss (P less than 0.001), anorexia (P less than 0.005), abdominal pain (P less than 0.05) and abdominal lump (P less than 0.05), compared to proximal carcinomas. Dysphagia was, however, more likely to be present in patients with proximal carcinomas (P less than 0.001).