Role of novel insecticides in crop protection and their selectivity to natural enemies: A review

In the present context of pest management in major crops, as the nature of pest pressure evolves, the requirement of new research-based tactics for pest control becomes a continuous process. Insecticide chemistry plays a major, if not dominant role in these developments. In this review, the toxicological aspects of new novel insecticides against crop pests and their selectivity to natural enemies have been discussed.The progress achieved in toxicological research has introduced new insecticides in crop protection during last two decades which are quite different over the existing groups in terms of chemistry and mode of action. It is evident from their mode of action that these chemicals target alternate physiological and biochemical effect. However, it is important to maintain the diversity in chemistry of insecticides for maximizing flexibility, precision and stability in pest management. In recent years, several new insecticide groups viz., neonicotinoids, butenolides, tetronic and tetramic acid derivatives, oxadiazines, diamides, ketoenols, phenylpyrazoles, pyridines, flonicamid, mitochondrial electron transport inhibitor (METI) acaricides, diafenthiuron, tetrazines, oxazolines, and insecticides from soil microorganisms such as avermectins, milbemycins, spinosyns, pyrrole insecticides and insect growth regulators (IGRs) have been discovered and commercialized for agricultural pest management. The ability of these new groups of insecticides to be effective at low rates or doses, high level of selectivity, greater specificity to target pests along with low toxicity to non-target organisms and the environment, replaced many conventional compounds. The conservation of beneficial organisms like natural enemies and pollinators is the fundamental principle of integrated pest management (IPM). Majority of new insecticide groups are safer and fit well into IPM. It is perceived that in the process of entry of new chemical insecticides in crop protection there is a gradual shift from traditional chemicals to selective novel groups which have minimal side-effects on natural enemies of the pests. These selective insecticides have less adverse impact on the conservation and multiplication of bio agents which can be used in a compatible manner with other tools of IPM. The new chemistries are emphasizing to account separately for possible non-target effects on predators, parasitoids, and pathogens. These factors are becoming increasingly important as the agricultural sector moves away from highly persistent broad-spectrum insecticides to more selective rapidly decaying products.

Assessment of salinity tolerance based upon morpho-physiological attributes in white jute (Corchorus capsularis L.)

Aim: A study was conducted to evaluate the salinity tolerance of white jute (C. capsularis) cultivars. Methodology: Five white jute cultivars were assessed for different salinity concentrations (0, 100, 150, 200 and 250 mM NaCl) in a split plot design with three replications per concentration under greenhouse condition. A total of fifteen plants were sampled from each treatment ten days after treatment with NaCl to determine morphological and physiological parameters. Results: Increased NaCl concentrations reduced all the morphological and physiological parameters such as plant height, root length, number of leaves, leaf area, shoot and root dry weight, relative leaf water content (RLWC), chlorophyll, protein, proline content, K+ accumulation in shoot and leaves, but water saturation deficit (WSD) and Na+ contents were increased in the shoot and leaves. Interpretation: The study revealed that among all cultivars assessed JRC-532 and JRC-321 showed relatively better performance against salt stress whereas cultivar JRC-517 was found more susceptible to salt stress.

Role of non-lipid risk factors like hs-CRP, uric acid and thyroid stimulating hormone in metabolic syndrome

Background: Metabolic syndrome is the cluster of diseases which arises due to excess of plasma glucose, cholesterol, fatty acids, blood pressure and obesity. The role of lipids in the development of MetS had been extensively studied. Though some non-lipid factors like hsCRP, uric acid and TSH level also remain elevated in the serum of the MetS patients, the role of these non-lipid risk factors remain incompletely understood. The objective of this study was to investigate which of these factors better predicts Mets, in order to help prevention and early detection of MetS and its associated type 2 diabetes mellitus and cardiovascular diseases. Aim and objectives was to study the significance of serum highly sensitive C-reactive protein (hs-CRP), serum uric acid (SUA) and thyroid stimulating hormone (TSH) levels in metabolic syndrome.Methods: A total of four hundred and fifty subjects (211 men and 239 women) aged ≥35 years attending the hospital were divided into three groups based on the components level of MetS as control (CS), normal (MS) and severe (SMS) MetS groups. Their fasting blood sample were taken and analyzed for the serum hs-CRP, uric acid and TSH levels. The result showed that the mean hs-CRP and uric acid levels were significantly higher in Metabolic Syndrome group (MS) and in Severe Metabolic Syndrome group (SMS) when compared to control group. But the mean TSH levels were more in MS group and in SMS group than the control which was statistically not significant. The analysis of relative significance of these risk factors showed that serum hs-CRP level had a positive linear correlation with the severity of MetS whereas, the TSH level was significantly high only in SMS and the uric acid level was not correlated with the MetS.Results: Our study revealed that type II (absence of sutural bones) was commoner than type I (presence of type I) asterion. The asterion was 4.82±0.58 cm from tip of the mastoid process on the right side and 4.70±0.70 cm on the left. It was greater in males than in females, p value being statistically significant (P = 0.00 and P = 0.02 for right and left sides respectively). The distance of asterion from supramastoid crest was 4.22±0.73 cm on the right and 4.23±0.58 cm on the left. The distance in males was more than in females. The P value 0.00 was statistically significant on the right side. Regarding the position of the asterion in relation to transverse sinus, it was on the transverse sinus in 62% cases, below it in 32% and above in 6%.Conclusions: In the present study, there was higher mean serum hs-CRP level in patients with metabolic syndrome which showed a linear increase with increasing number of components of the metabolic syndrome. Though available literature indicated that hyperuricemia adult subjects tend to develop MetS more frequently our findings showed this increase was not dependent on the severity of MetS. Also, significantly high TSH levels were found only in severe MetS suggest that as per this study the serum hs-CRP values may be consider as the diagnostic criteria for metabolic syndrome and helps to improve future prediction of development of type 2 DM and cardiovascular diseases.

Hepatoprotective activity of methanolic extract of rhyncosia beddomei baker leaves against carbon tetrachloride induced hepatotoxicity.

Rhyncosia beddomei Baker commonly known as Adavi-kandi, Vendiaku in Telugu belongs to the family Fabaceae.In the present study, the methanolic extract of Rhyncosia beddomei leaves was evaluated for its hepatoprotective effect against CCl4 induced hepatic injury in rats. Alteration in the levels of biochemical markers of hepatic damage like SGOT, SGPT, ALP, triglycerides, bilirubin, total proteins and liver weight were tested in both treated and untreated groups. CCl4 (1ml/kg) enhanced the SGPT, SGOT, ALP, triglycerides, liver weight and reduced total proteins significantly. Treatment with methanolic extract of Rhyncosia beddomei leaves (200mg/kg and 400mg/kg) has brought back the altered levels of altered levels of biochemical markers significantly to the near normal levels in the dose dependant manner. Histopathological studies supported the hepatoprotective activity of Rhyncosia beddomei Baker.

Formulation and evaluation of sustained releasematrix tablets of glimepiride based on combinationof hydrophilic and hydrophobic polymers.

The objective of this study was to develop sustained release tablets of glimepiride by wet granulation method based on combination of hydrophilic (HPMC15cps, HPC) and hydrophobic (Ethyl cellulose) polymers. The drug excipient mixtures were subjected to preformulation studies. The tablets were subjected to physicochemical studies, in- vitro drug release, kinetic studies and stability studies. FTIR and DSC studies shown there was no interaction between drug and polymers. The physicochemical properties of tablets were found within the limits. Glimepiride is a first third generation sulphonyl urea agent for the treatment type II diabetes mellitus. The drug release from the optimized formulation was extended for a period of 12 hrs. The kinetic treatment showed that the release of drug follows first order models. The optimized formulations were subjected to stability studies and shown there were no significant changes in drug content, physicochemical parameters and release pattern. Results of the present study indicated the suitability of the above mentioned polymers in the preparation of sustained release formulation of glimepiride.

Ostema of Mandible - A Case Report.

Osteoma is an slow growing asymptomatic lesion. It is an benign tumour composed of mature compact or cancellous bone. It can be central, peripheral or extraskeletal.The central osteoma arises from the endosteum, the peripheral osteoma from the periosteum and the extra-skeletal soft tissue osteoma usually develops within the muscle [1] . Here a case report of osteoma in the lower border of the angle of the mandible in a 14 year old patient is presented. The osteoma was surgically excised.

Chromosomal breakage in myelodysplatic syndrome.

The myelodysplastic syndrome (MDS) represents a group of clonal hematological disorders characterized by progressive cytopenia reflecting defects in erythroid, myeloid and mega karyocytic maturation. The incidence of MDS is greter in older age groups. Detailed studies on MDS from India are not available. Cytogenetic study using GTG-banding and FISH revealed 54.5% clonal chromosomal abnormalities. We have carried out chromosomal breakage study from peripheral blood cultures induced with mitomycin C, in karyotypically normal MDS (49) and 15 (30.6%) showed significant (p < 0.001) increase in chromosome damage compared to controls. Among 22 occupationally exposed MDS, 6 (27.3%) showed a high frequency of chromosome breakage while in the non-exposure (n=27) group, high chromosome breakage was noted in 9 (33.3% ) MDS patients. Our results suggest that the high chromosome damage may be due to acquired Fanconi anemia which leads to multiple defects in chromosomes and clonal chromosome anomalies.

Pericentric inversion of chromosome 9[inv(9)(p12q13)]: Its association with genetic diseases.

Background: The chromosomal polymorphism of short arms of acrocentric chromosomes and heterochromatin variation of Chromosomes 1, 9, 16 and Y have been reported in humans. The pericentric inversion of Chromosome 9 is commonly seen in normal humans and the frequency estimated to be 1 to 3% in general population and inherited in mendalian fashion or might occur spontaneously without any clinical significance. Aim: The aim of the study was to study the frequency of inv(9) and its clinical correlation with human genetic diseases. Materials and Methods:0 The chromosomal analysis using GTG-banding was carried out in 3,392 cases suspected with genetic diseases. Results: The pericentric inversion frequency of different chromosomes in our study was 1.24% and frequency of inv(9)(p12q13) was high (64.29%) compared to other pericentric inversions in our study. A high frequency (9.33%) of inv(9)(p12q13) was detected in children with dysmorphic features and congenital anomalies. Conclusion: As a high frequency of inv(9)(p12q13) detected in children with dysmorphic features, the inv(9) definitely have a role in the abnormal phenotype development. During inversion event there might be loss or suppression of euchromatin chromosome region and hence detailed chromosomal break point study is important to understand the clinical significance of the pericentric inversion of Chromosome 9.

Pharyngeal airway changes following mandibular setback surgery.

Treatment of dentofacial deformities with jaw osteotomies has an effect on airway anatomy and therefore mandibular setback surgery has the potential to diminish airway size. The purpose of this study was to evaluate the effect of mandibular setback surgery on airway size. 8 consecutive patients were examined prospectively. All patients underwent mandibular setback surgery. Cephalometric analysis was performed preoperatively and 3 months post operatively with particular attention to pharyngeal airway changes. Pharyngeal airway size decreased considerably in all, patients thus predisposing to development of obstructive sleep apnea. Therefore, large anteroposterior discrepancies should be corrected by combined maxillary and mandibular osteotomies.

Nucleolar organising region evaluation using new NOR FISH probe.

We have carried out chromosomal analysis in a couple with repeated spontaneous abortions (RSA). The chromosomal analysis of male revealed 15ps+ and the chromosome 15 appeared as submetacentric, C- group chromosome. First time we have attempted fluorescence in situ hybridization (FISH) using NOR probe (dJ1174 A5) and FISH analysis revealed NOR duplication on chromosome 15 which was also quantitated using Q-FISH software. The identical NOR duplication also detected in chromosome preparations from products of conception. However, NOR studies in large group of patients is necessary to understand the role of NORs in RSA.

Increase in minimum inhibitory concentration to quinolones and ceftriaxone in salmonellae causing enteric fever.

Multidrug resistance among Salmonella typhi is well known. Reports of treatment failure in enteric fever with Ciprofloxacin made us undertake this study to determine the antibiotic susceptibility pattern of S. typhi and S. paratyphi A isolated from typhoid bacteremia cases, by disc diffusion and MIC by broth dilution method. A total of 50 strains were tested, 48 of Salmonella typhi and 2 of S. paratyphi A. The disc diffusion method was done using ampicillin, chloramphenicol, cotrimoxazole, tetracycline, ciprofloxacin, ofloxacin, cefuroxime and ceftriaxone as antibiotics. The MIC was performed using ciproloxacin, ofloxacin and ceftriaxone based on standard procedure. ACCOT resistance as determined by disc diffusion method was seen in 68% of isolates. All the strains remained susceptible to flouroquinolones cephalosporins and aminoglycosides. The MIC of ciprofloxacin, ofloxacin and ceftriaxone were in the recommended range of susceptibility as given by NCCLS, 14 (28%) strains had MIC of ciprofloxacin greater than 0.5 ug/ml with 4 strains having an MIC of 1.56 ug/ml; 25 (50%) strains had MIC of ofloxacin greater than 0.5 ug/ml and 20 (40%) strains had MIC of ceftriaxone greater than 0.5 ug/ml. The high levels of MIC of ciprofloxacin may account for treatment failure cases. The rising levels of MIC of ofloxacin and ceftriaxone in S. typhi and S. paratyphi is also of concern. We document here the emergence of high levels of MIC not only to ciprofloxacin, but also ofloxacin and ceftriaxone in S. typhi and S. paratyphi A. We recommend that MIC levels of ofloxacin and ceftriaxone should be monitored along with ciprofloxacin in treatment failure cases of enteric fever.

Hormonal Studies In Primary Amenorrhea.

Values of serium Tri ido Thyronine (T3), Thyroxine (T4) thyroid stimulating hormone (TSH) Follicle stimulating hormones (FSH) are established in 70 primary amenorrhea cases. In chromosomally abnormal cases, the follicle stimulating values are elevated and it is further interesting to note that all these cases have mossaicism 45,X/46,XX. In 4 chromosomally abnormal cases Tri ido thyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH) have shown abnormal values. Out of these 4 cases, 2 cases were with 45,X and 2 cases with 45,X/46,XX chromosome complement. All these cases have gonadal dysgenesis, with short stature and underweight.

Synthetic peptides related to laminin pentapeptide (YIGSR) fragment.

The synthetic laminin pentapeptide amide fragment (LF), Tyr-Ile-Gly-Ser-Arg-NH2 corresponding to a part of B1 chain of the glycoprotein, laminin, and six of its analogues having structural modifications at positions 1, 3 and 4 were synthesized by solid phase method employing mainly 9-fluorenylmethoxycarbonyl-amino acid trichlorophenyl esters as coupling agents and Merrifield resin as the solid support. Their biological activities were studied in vivo by lung tumor colonization assay and in vitro by cell adhesion assay. The activity of synthetic LF was found to correlate with the earlier reported results in both in vivo and in vitro assays. Among the analogues made, [Tyr4] LF and [Thr4]LF were found to inhibit the lung tumor colonies more efficiently than LF itself in the in vivo assay whereas [D- Ser4]LF exhibited almost the same inhibition as LF.

Synthetic peptides related to the delta-receptor agonist, dermorphin gene associated peptide.

The delta-receptor selective dermorphin gen associated peptide (DGAP) and five of its analogues having structural modifications at positions 2, 4 and 5 were synthesized by the solid phase method using 9-fluorenylmethoxycarbonyl amino acid trichlorophenyl esters as coupling agents and rho-benzyloxybenzyl alcohol resin as the solid support. The delta-receptor selectivity of these peptides was determined by guinea pig ileum and mouse vas deferens assays. The latter assay was carried out using modified Kreb's solution aerated with pure oxygen instead of carbogen. All the synthetic peptides were found to be delta-receptor selective.

Tryptophan as an endogenous photosensitizer to elicit harmful effects of ultraviolet B.

Owing to stratospheric ozone depletion (SOD) the natural flux of ultraviolet B (UVB) radiation (290-320 nm) is likely to increase on the earth surface. In our efforts to identify endogenous chromophores which may absorb significantly in the UVB range and subsequently induce phototoxic reactions, we have observed that tryptophan (Trp) was quite photoreactive under UVB. It enhanced considerably the oxygen-dependent photooxidation of tyrosine (Tyr) to dopachrome, a precursor of melanin. Our data suggest that UVB-sensitized Trp produces singlet oxygen (1O2) and superoxide radicals (O2-.), and these reactive forms of oxygen may contribute to membrane-, cytoplasm- and DNA-damaging effects. In the event of an increasing SOD level, other UVB chromophores may also exhibit similar phototoxic properties to lead to a definitive imbalance between cell life, injury and death.

Improved solid phase synthesis of luteinizing hormone releasing hormone analogues using 9-fluorenylmethyloxycarbonyl amino acid active esters and catalytic transfer hydrogenation with minimal sidechain protection and their biological activities.

Using mainly 9-fluorenylmethyloxycarbonyl amino acid 2, 4, 5-trichlorophenyl esters in the presence of 1-hydroxybenzotriazole and the solid support p-alkoxybenzyl alcohol resin, synthesis of luteinizing hormone releasing hormone analogues was carried out with minimal side-chain protection. Catalytic transfer hydrogenation was employed for removal of NO2 and Z-groups from Arg and < Glu respectively avoiding the use of HF and this led to good yields. An aromatic, hydrophilic amino acid, D-(p-hydroxyphenyl) glycine was incorporated into luteinizing hormone releasing hormone molecule along with other modifications. The agonistic as well as antagonistic activities of all the peptides have been studied.