Benzophenyl urea insecticides – useful and eco-friendly options for insect pest control

Insecticides play a very important role in increasing production by protecting crops from destructive insect pests. But indiscriminate use of conventional and broad spectrum insecticides, leads to development of resistance, resurgence and environmental pollution. Therefore, it is necessary to select new, safe and less persistent products for ecofriendly and sustainable pest management. Benzophenyl urea based insecticides fit well in this aspect. These are basically inhibitors of the chitin synthesis in insects which make them strong candidate for the integrated pest management. Extensive research has been carried out on different aspects to assess the potentiality and environment friendliness of this group of insecticides. Thus, the aim of this review is to gather comprehensive information about benzophenyl urea insecticide related to its development, mode of action, bio-efficacy, environmental fate and eco-toxicity, which may be helpful for the researchers for future endeavour.

A Case Report of Thoracic Outlet Syndrome with Vascular Complications due to Cervical Rib.

Thoracic outlet syndrome (TOS) is recognized in approximately 8% of the population. Its manifestations may be neurologic or vascular or both, depending on the component of the neurovascular bundle predominantly compressed. The diagnosis is suspected from the clinical picture and investigations. Treatment is initially conservative but persistence of significant symptoms, which occurs in approximately 5% of patients with diagnosed TOS, is an indication for cervical rib and or first rib resection.1 We report the case of a young woman having a left sided cervical rib. She had presented with clinical features of both neurogenic and arterial TOS. Surgical resection of the cervical rib was performed uneventfully through a supraclavicular approach which resulted in complete relief of her symptoms.

A Case Report of Middle Aortic Syndrome: A Rare Vascular Disorder.

The middle aortic syndrome (MAS) is rare (about 0.5-2% of all the cases of aortic coarctation) vascular disorder characterized by severe narrowing in the descending thoracic aorta, abdominal aorta, or both. It can be congenital or acquired due to several conditions.MAS may present clinically as uncontrolled hypertension, abdominal angina or lower limb claudication. Surgical treatment is effective in controlling symptom and improves life expectancy.

Evaluation of Pulmonary Function after Off- Pump Coronary Artery Bypass Graft Surgery with Thoracic Epidural Analgesia.

Background: A substantial reduction of lung volumes and pulmonary function follows cardiac surgery. Pain may prevent effective breathing and coughing, as thoracic epidural analgesia may reduce post operative pain and improve early post operative pulmonary function. We tested the effect of thoracic epidural analgesia (TEA) on pulmonary function after off- pump coronary artery bypass (OPCAB) graft surgery. Methods: 60 patients undergoing off- pump coronary artery bypass (OPCAB) graft surgery were nonrandomized in to two groups. Group-I (30 patients) receiving thoracic epidural analgesia along with general anaesthesia (G/A) but Group-II (30 patients) receiving general anaesthesia alone. Total ventilation time, intensive care unit (ICU) stay, spirometric data, arterial blood gas (ABG) and X-ray chest (CXR) were recorded in postoperative follow-up period. Results: Thirty patients were enrolled in each group. The demographics of the groups were similar. Patients in the epidural group had significantly less pain on the operative day and for the next 2 days. Total ventilation time in hours in Group-I was 6.4±1.0 and in group-II was 10.1±1.8 hours respectively. FVC and FEV1 were significantly different in group-I than group-II. On the postoperative period, ABG was done pre and postoperative period in both groups of patients. Significant differences was found in pao2 and paco2, half an hour after extubation, 1st postoperative day, 2nd postoperative day (p<0.05). Postoperative CXR revealed significant pulmonary complication in group-II than group-I, higher in the epidural group on the first and second postoperative days. There were no complications related to epidural hematoma and no permanent neurologic squeal. Conclusion: Thoracic epidural analgesia yields a slight, but significant improvement in pulmonary function most likely due to a more profound postoperative analgesia.

A study on intranatal care practices in a district of West Bengal.

A study was conducted at Birbhum district of West Bengal among mothers who delivered in last one year to generate area-specific community-based data on the proportion of home deliveries, assistance during conduction of delivery and the intranatal care practices followed in the district. A multistage 40 cluster sampling method was used to study 320 mothers in the district. 37.81% deliveries were conducted at home. About 25% deliveries were conducted by untrained birth attendants, unqualified practitioners or relatives and friends. In 85.13% of home deliveries, DDK was not used. 68.6% home deliveries were conducted on the floor without any clean covering sheet. Though a clean instrument was used to cut the cord in 86.78% of home deliveries, a clean cord tie was used in only 24.89% cases. In 36.36% home deliveries, something was applied on the cord stump. High proportion of deliveries assisted by untrained persons and high magnitude of faulty intranatal care practices observed in the study require urgent and appropriate intervention.

Routine primary immunization: status in two district of West Bengal.

The study was conducted at Birbhum and Purba Medinipur districts of West Bengal to assess the routine primary immunization coverage following 40 cluster sampling technique was used to study 320 children in each of the districts. BCG coverage was found to be 79.69% at Birbhum and 84.38% at Purba Medinipur. Only 62.81% children at Birbhum and 67.81% children at Purba Medinipur received all the three primary doses of DPT. Regarding OPV, coverage with three primary doses were only 65% and 66.88% at Birbhum and Purba Medinipur respectively. Measles vaccine coverage was very poor at both the districts, 55.94% at Birbhum and 62.5% at Purba Medinipur. Full primary immunization was observed 53.13% and 61.56% in Birbhum and Purba Medinipur respectively. High drop-out rate was identified as a major deficiency in both the districts. Of the children who received at least one routine vaccine, more than 1/3rd at Birbhum and more than 1/4 th at Purba Medinipur did not turn up later for completion of their primary vaccine doses. It is evident that routine immunization coverage was poor in both the districts and it seems there has been no improvement in situation for last few years. It will influence not only the child morbidity and mortality situation but also will jeopardize the paralytic polio eradication programme. Urgent intervention should be undertaken to address the large number of non-immunized children as well as high proportion of drop-outs.

A study on arsenical dermatosis in rural community of West Bengal.

The spatial distribution of chronic arsenicosis due to consumption of arsenic contaminated tube well water in different districts of West Bengal was gradually unfolding since 1983. Arsenical dermatosis was found to be the commonest and earliest manifestation of chronic arsenic toxicity. This study was conduct in Baruipur block of South 24 Parganas district of West Bengal. Total 313 people selected from three randomly selected villages with reported arsenic contamination in tube well water and 342 people living three randomly selected villages without such evidence of contamination were examined as control population. 5.97% of exposed population and 2.05% of unexposed population showed melanosis (p < 0.01). Moreover, 5.11% of exposed population and 0.88% of unexposed population showed keratosis (p < 0.01). The prevalence of dermatosis among exposed population was also seen to have increased with increasing age, from 7.19% in 0-19 year age group to 37.50% in above 40 year group (p < 0.001). Prevalence was also found to be more with increase in level of contamination. The prevalence rate of dermatosis among unexposedgroup was 2.92%. But age adjusted prevalence rate among exposed group was 19.08% at arsenic contamination level of 0.487 ppm. Mean arsenic concentration in nail and hair samples of exposed group was also found higher than the prescribed limit.

An epidemiological study of the risk factors of occupational diseases in coal handling plant of a thermal power station.

Anthropometry and morbidity profile of fifty randomly selected workers of coal handling plant at a thermal power station of West Bengal having at least five years experience were studied. The mean value of their age, duration of present job and Body Mass Index (BMI) were 34.8 years, 7.86 years and 19.24 respectively. As they were exposed to coal dust (Av. concentration 300-350 mg/M3 of air), warmth (Ambient temperature 40 +/- 5 degrees C), humidity (Relative humidity 80 +/- 5%) and noise [Av. 80 dB(A)], respiratory system was most commonly (72%) effected followed by greying of hair (5.6%), Cloth dusters used by some could not render any discernable protective effect. Addiction was also prevent (62%). Use of proper protective equipments (PPE) supplemented by adequate preplacement and periodic medical examination followed by successful rehabilitation were suggested.

Declining trend in routine UIP coverage.

Routine UIP coverage status in the state of West Bengal and three selected Municipal Corporation areas (Calcutta, Howrah and Siliguri) were studied during 1997-98 and 1998-99. Also, UIP coverage status in the 'high risk' areas of the State (areas which reported Polio cases during 1998) was studied during 1998-99. UIP coverage in the state of West Bengal was only 54.3% in 1997-98, which further declined to 48.1% in 1998-99. In the three urban areas, UIP coverage ranged between 57.3%-70.9% in 1997-98, which further declined to 29.6%-47.1% in 1998-99. Antigenwise coverage revealed very poor performance with DPT3, OPV3, and Measles in 1997-98 and further decline in 1998-99. Dropout rate was also very high. In 1998-99 drop-out rate ranged between 30.1% to 54.2% in different studied areas. Some other studies suggested that PPI activities, which are very visible and targetted programme, may adversely affect routine UIP services. There is urgent need for further probing to identify the reasons for such poor state of affairs, keeping PPI angle in mind and to initiate remedial measure urgently.

A four year follow up study of filaria specific IgE response in individuals with hydrocele.

BACKGROUND & OBJECTIVES: Hydrocele is the most common clinical manifestation in males infected with Wuchereria bancrofti. IgE response to a filarial allergen Sd30 was evaluated in hydrocele patients living in a W. bancrofti endemic region of Orissa, India. METHODS: IgE levels to Sd30, an antigenic fraction isolated from Setaria digitata, were determined by ELISA in sera from patients of filariasis (n = 93). IgG and IgM levels were also determined. RESULTS: It was observed that microfilaraemic patients with hydrocele (n = 16) exhibited considerably reduced (P < 0.01) IgE levels in comparison to hydrocele patients without microfilariae (n = 27) and to other filarial groups (elephantiasis, asymptomatic microfilaraemics). The reduced IgE response in microfilariae positive patients with hydrocele persisted even after a gap of four years in the majority of patients. INTERPRETATION & CONCLUSIONS: The results show low IgE levels in microfilaraemic patients with hydrocele in comparison to other groups in filaria endemic regions. The exact mechanism of this reduction in IgE is not known but these patients make a distinct group in filaria endemic regions and should be considered separately for immunological evaluation.

Laryngeal changes following long-term stenting with polyvinyl chloride tubes.

BACKGROUND. To treat tracheal stenosis and permit wound healing to occur an inert stent is required which resists the contraction process and prevents re-stenosis. The newer stents of polyvinyl chloride are not readily available in India and endotracheal tubes are used in many centres. In our centre polyvinyl chloride tubes are used nasotracheally for prolonged periods. We prospectively studied the pattern of laryngeal changes that occur because of prolonged nasotracheal stenting with polyvinyl chloride tubes. METHODS. The incidence and pattern of laryngeal changes due to stents was prospectively studied at the time of removal of stents, using an operating microscope. Twenty-nine patients underwent tracheal reconstructive surgery for tracheal stenosis (post-intubation or post-tracheostomy) and tracheal injuries. RESULTS. Twelve different lesions were noted and their pattern was related to the period of stenting. Fibrosis, fibrous band formation and webs were noted after four weeks. A high incidence of laryngeal changes was seen in all age groups with an overall incidence of 79% (males 79%; females 88%; adults 82%, children 75%). The mean (SD) duration of stenting was 50 (33) days. Patients with laryngeal changes had a significantly (p < 0.05) longer duration of stenting [56 (34) days] compared to those without any lesion [29 (15) days]. CONCLUSIONS. After four weeks of stenting the severity and incidence of laryngeal changes increase. We recommend restriction of the use of polyvinyl chloride stents to less than four weeks to prevent permanent laryngeal damage.

Induction of metachromasia and circular dichroism in the dye 1,9-dimethyl methylene blue by ATP.

The theoretical prediction of induction of metachromasia [V Czikkely, H D Foersterling & H Kuhn (1970), Chem Phys Lett, 6,207] in a dye by a polyanion having only four to six anionic sites is proved experimentally, for the first time, in ATP--1.9-dimethyl methylene blue system. The findings show that ATP induces metachromasia in the dye at neutral pH, when ATP molecule remains fully charged providing four anionic sites to the dye cations. Conductometric titration shows that the dye molecules bind stoichiometrically to ATP (four dyes/ATP). However ATP at acidic pH and ADP and AMP at any pH fail to induce metachromasia. This is also the first report of induction of circular dichroism in bound dyes by ATP. Though the chiral moiety of ribose sugar in ATP may induce dichroism in the bound achiral dyes, the observed high molar ellipticity values indicate aggregation of bound dyes with twist in one sense initiated by the twisted conformation of the triphosphate chain in ATP. This inference on the state of conformation of ATP in its native environment is in agreement with that derived from PMR and spin lattice relaxation technique. It is thus interesting that the conformation of crystalline disodium ATP, as concluded from X-ray crystallography, is maintained by tetrasodium ATP in dilute aqueous solution--the native environment of ATP.

Enzymes of carbohydrate metabolism in fast-growing Rhizobium grown on hexoses or succinate.

Enzymatic evidence supports that succinate mediates repression of hexose-catabolising enzymes in fast-growing Rhizobium sp. (Cicer arietinum). Enzymes of the Embden-Myerhof-Parnas, Entner-Doudoroff and pentose phosphate pathways were found present in hexose-grown cells but not in succinate-grown cells. These however could be induced by the presence of hexoses.

Role of S gene product of bacteriophage lambda in host cell lysis.

Studies with the induced lysogens of λ S+R+, λS–R+, λS+R– and λS–R– phages have shown that while the S gene product is essential for the action of intracellular R gene product to release the periplasmic alkaline phosphatase in the presence of EDTA, the latter gene product can bring about this effect while acting on Escherichia coli cells from outside, in the absence of functional S gene product; chloroform, could help the intracellular R gene product in effecting bacterial lysis in the absence of S gene product. These result support the premise that the S gene product facilitates the R gene product in crossing the cytoplasmic membrane into the periplasmic space such that the latter can act on the peptidoglycan layer of the host cell thus causing both the release of alkaline phosphatase and cell lysis.