This study investigated the working hypothesis that two widely used organophosphate pesticides; Nuvan and Dimecron, exert toxic effects in Drosophila. Transgenic D. melanogaster (hsp70-lacZ) was used as a model for assaying stress gene expression and AchE activity as an endpoint for toxicity and also to evaluate whether stress gene expression is sufficient to protect against toxic insult of the chemicals and to prevent tissue damage. The study was extended to investigate the effect of the pesticides on the life cycle and reproduction of the organism. The study showed that Nuvan affected emergence of the exposed flies more drastically than Dimecron and the effect was lethal at the highest tested concentration (0.075 ppm). While Nuvan at 0.0075 and 0.015 ppm concentrations affected reproduction of the flies significantly, the effect of Dimecron was significant only at 0.015 and 0.075 ppm. Nuvan-exposed third-instar larvae exhibited a 1.2-fold to 1.5-fold greater hsp70 expression compared to Dimecron at concentrations ranging from 0.0075 to 0.075 ppm following 12 and 18 h exposure. While maximum expression of hsp70 was observed in Nuvan-exposed third-instar larval tissues following 18 h exposure at 0.075 ppm, Dimecron at the same dietary concentration induced a maximum expression of hsp70 following 24 h exposure. Further, concomitant with a significant induction of hsp70, significant inhibition of AchE was observed following chemical exposure and temperature shock. Concurrent with a significant decline in hsp70 expression in Nuvan-exposed larvae after 48 h at 0.075 ppm, tissue damage was evident. Dimecron-exposed larvae exhibited a plateau in hsp70 induction even after 48 h exposure and moderate tissue damage was observed in these larvae. The present study suggests that Nuvan is more cytotoxic than Dimecron in transgenic Drosophila melanogaster.

Acetylcholinesterase↗

PubMedDate not supplied

Effects of pH and salt concentration on the hydrolysis of a benzo[alpha]pyrene 7,8-diol-9,10-epoxide catalyzed by DNA and polyadenylic acid.

The time-dependent absorbance change that occurs when benzo[alpha]pyrene 7,8-diol-9,10-epoxide is added to solutions of calf thymus DNA has been shown, by an unequivocal chromatographic method, to correspond to DNA-catalyzed hydrolysis of the diol-epoxide. At 25 degrees C and mu = 0.10, the kinetics of the reaction of the diol-epoxide with polyadenylic acid or DNA are consistent with preequilibrium formation of a non-covalent complex between the diol-epoxide and the polynucleotide or DNA, followed by hydrolysis of the bound epoxide by a process that is first-order in hydronium ions. Cacodylic acid also catalyzes the hydrolysis of the epoxide bound to polyadenylic acid. The rate of the DNA-catalyzed hydrolysis exhibits little or no enantiomeric selectivity for the diol-epoxide. DNA catalyzed hydrolysis of the diol-epoxide is extraordinarily sensitive to the salt concentration in the reaction medium: the rate of hydrolysis of the bound epoxide at pH 7 is retarded by a factor of approximately 45 in the presence of 0.1 M sodium chloride compared to a 1 mM buffer containing no added salt. Thus, studies of the interactions of DNA with carcinogenic diol-epoxides must take into account the ionic environment of DNA within the cell.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗

PubMedDate not supplied

Endoscopic and histologic appearance of the gastric mucosa in patients with portal hypertension.

To assess reliability of the endoscopic and histologic appearance of the gastric mucosa for diagnosing portal hypertension, 50 patients with portal hypertension and 1323 controls were studied. Endoscopic evidence of mild gastritis was seen more frequently in patients with portal hypertension than in the control group (42% vs. 13.1%, p less than 0.001). The mosaic sign was also seen more frequently in patients with portal hypertension compared with controls (14% vs. 0.9%, p less than 0.001). However, the mosaic sign was found to be nonspecific, and the sensitivity for diagnosis of portal hypertension was only 14%. Biopsy specimens from the stomach of all patients with portal hypertension and 100 controls with a normal endoscopic appearance revealed mucosal vascular congestion in 72% of patients with portal hypertension compared with 59% of controls (NS). There was no correlation between endoscopic and histologic evidence of congestive gastropathy. Similarly, there was no correlation between the severity of mucosal vascular congestion and the degree of inflammatory changes observed in the biopsy specimens; both in the control (r = 0.1) and in patients with portal hypertension (r = 0.14). It is concluded that endoscopic and histologic features of the gastric mucosa in patients with portal hypertension are of low sensitivity and nonspecific and cannot be used to diagnose portal hypertension.

Biopsy↗

PubMedDate not supplied

An experimental study of different contrast media in the epidural space.

In the experimental study of different contrast media, metrizamide has been found to be very safe for epidurography as no clinical, radiologic, or histologic changes after epidural injection were seen. Next in order was meglumine iothalmate. However, sodium containing salts like sodium acetrazoate and sodium iothalmate were found to be very irritating to the nerve roots and the spinal cord and, therefore, should not be used for epidurographic studies.

Animals↗

PubMedDate not supplied

Suitable bases for patch testing in tropical countries.

Patients suspected of having contact dermatitis due to topical medicaments were patch tested with various bases to evaluate the most suitable base for tropical countries. Plastibase and polyethylene glycol 400 produced the least positive reactions. Both were therefore found to be suitable bases, although polyethylene glycol had more positive results than plastibase.

Dermatitis, Contact↗

PubMedDate not supplied

Plastibase: a new base for patch testing of metal antigens.

Explore the source record for details and available documents.

Drug Hypersensitivity↗

PubMedDate not supplied

The Loeffler's methylene blue stain: an inexpensive and rapid method for detection of Helicobacter pylori.

Loeffler's methylene blue, commonly used as a counter-stain for acid fast bacilli, was used to detect Helicobacter pylori in paraffin sections and touch smears of gastric mucosal biopsies from 15 patients with duodenal ulcer and 35 with non-ulcer dyspepsia, and the results were compared with the modified Giemsa stain. The time taken to stain smears by Loeffler's methylene blue was approximately 10 min and the results correlated well with those stained by the modified Giemsa stain. However, the Loeffler's methylene blue method was found to be simpler, quicker and cheaper than the modified Giemsa stain.

Azure Stains↗

PubMedDate not supplied

Diagnosing ascites: value of ascitic fluid total protein, albumin, cholesterol, their ratios, serum-ascites albumin and cholesterol gradient.

Ascitic fluid total protein, albumin, cholesterol, their ascites/serum ratios, serum-ascites albumin and cholesterol gradients were measured for their ability to differentiate cirrhotic, malignant and tuberculous ascites in 76 patients. The mean +/- s.d. ascitic fluid total protein, albumin, cholesterol, their respective ascitic fluid/serum ratios in cirrhotic ascites were lower than malignant and tuberculous groups (P < 0.001 for each). The difference between malignant and tuberculous groups was significant for ascitic fluid/serum total protein (P < 0.05) and ascitic fluid/serum albumin (P < 0.01) only. Mean serum-ascites albumin gradient in cirrhotics was higher than in the malignant and tuberculous groups (P < 0.001 for each). The difference between malignant and tuberculous groups was significant (P < 0.01). Mean +/- s.d. serum-ascites cholesterol gradient in cirrhotics was higher than that in malignant and tuberculous groups (P < 0.001 for each). The difference between malignant and tuberculous groups was also significant (P < 0.01). Both serum/ascitic fluid total protein less than 0.5 and ascitic fluid cholesterol less than 55 mg/dL had 94% diagnostic accuracy for differentiating cirrhotic from malignant and tuberculous differentiating cirrhotic from malignant and tuberculous ascites. Serum ascitic fluid albumin gradient greater than 1.1 g/dL, ascitic fluid/serum albumin less than 0.65 and ascitic fluid albumin less than 2 g/dL had diagnostic accuracy of 92, 92 and 91%, respectively. Ascitic fluid total protein had diagnostic accuracy of 88%. None of the tests was able to differentiate between malignant and tuberculous ascites. Measurement of ascitic fluid cholesterol concentration is a simple method of differentiating cirrhotic from non-cirrhotic ascites.

Albumins↗

PubMedDate not supplied

Herbicide banding and tillage system interactions on runoff losses of alachlor and cyanazine.

Herbicides transported to surface waters by agricultural runoff are partitioned between solution and solid phases. Conservation tillage that reduces upland erosion will also reduce transport of herbicides associated with the solid phase. However, transport of many herbicides occurs predominantly in solution. Conservation tillage practices may or may not reduce transport of solution-phase herbicides, as this depends on the runoff volume. Reducing herbicide application rate is another approach to minimize off-site transport. Herbicide banding can reduce herbicide application rates and costs by one-half or more. Our objective was to compare herbicide losses in runoff from different tillage practices and with band- or broadcast-applied herbicides. The herbicides alachlor [2-chloro-2',6'-diethyl-N-(methoxymethyl)acetanilide] and cyanazine [2-[[4-chloro-6-(ethylamino)-1,3,5-triazin-2-yl]amino]-2-methylpropionitrile] were broadcast- or band-applied to plots managed in a moldboard plow, chisel plow, or ridge till system. Herbicide concentration in runoff was largest for the first runoff event occurring after application and then decreased in subsequent events proportional to the cumulative rain since the herbicide application. When herbicides were broadcast-applied, losses of alachlor and cyanazine in runoff followed the order: moldboard plow > chisel plow > ridge till. Conservation tillage systems reduced runoff loss of herbicides by reducing runoff volume and not the herbicide concentration in runoff. Herbicide banding reduced the concentration and loss of herbicides in runoff compared with the broadcast application. Herbicide losses in the water phase averaged 88 and 97% of the total loss for alachlor and cyanazine, respectively. Cyanazine was more persistent than alachlor in the soil.

Acetamides↗

PubMedDate not supplied

Tillage and nutrient source effects on surface and subsurface water quality at corn planting.

This study quantified the effects of tillage (moldboard plowing [MP], ridge tillage [RT]) and nutrient source (manure and commercial fertilizer [urea and triple superphosphate]) on sediment, NH4+ -N, NO3- -N, total P, particulate P, and soluble P losses in surface runoff and subsurface tile drainage from a clay loam soil. Treatment effects were evaluated using simulated rainfall immediately after corn (Zea mays L.) planting, the most vulnerable period for soil erosion and water quality degradation. Sediment, total P, soluble P, and NH4+ -N losses mainly occurred in surface runoff. The NO3- -N losses primarily occurred in subsurface tile drainage. In combined (surface and subsurface) flow, the MP treatment resulted in nearly two times greater sediment loss than RT (P < 0.01). Ridge tillage with urea lost at least 11 times more NH4+ -N than any other treatment (P < 0.01). Ridge tillage with manure also had the most total and soluble P losses of all treatments (P < 0.01). If all water quality parameters were equally important, then moldboard plow with manure would result in least water quality degradation of the combined flow followed by moldboard plow with urea or ridge tillage with urea (equivalent losses) and ridge tillage with manure. Tillage systems that do not incorporate surface residue and amendments appear to be more vulnerable to soluble nutrient losses mainly in surface runoff but also in subsurface drainage (due to macropore flow). Tillage systems that thoroughly mix residue and amendments in surface soil appear to be more prone to sediment and sediment-associated nutrient (particulate P) losses via surface runoff.

Agriculture↗

PubMedDate not supplied

Time series analysis of out patients at Urban Health Centre, Suraj Kund, Meerut.

Time series analysis of out-patients at Urban Health Centre, Suraj Kund, Meerut, was done using the out-patient attendance of last five years, with the aim to find out the values to help in coping up with the problem of health administration and management. The least square method and ratio-to-trend method were adopted for calculating the secular trend and seasonal variations respectively. There was an increasing trend in out-patients attendance indicating the increasing popularity of the Urban Health Centre. It was found that in second and third quarter of the year the out-patient attendance increased extraordinarily due to various reasons. The two more aspects of time series, i.e. cyclical trend and irregular flactuation could not be analysed due to their insignificant impact over the health management system.

Analysis of Variance↗