Structure, localization and histone binding properties of nuclear-associated nucleosome assembly protein from Plasmodium falciparum

BACKGROUND

Nucleosome assembly proteins (NAPs) are histone chaperones that are crucial for the shuttling and incorporation of histones into nucleosomes. NAPs participate in the assembly and disassembly of nucleosomes thus contributing to chromatin structure organization. The human malaria parasite Plasmodium falciparum contains two nucleosome assembly proteins termed PfNapL and PfNapS.

METHODS

Three-dimensional crystal structure of PfNapS has been determined and analysed. Gene knockout and localization studies were also performed on PfNapS using transfection studies. Fluorescence spectroscopy was performed to identify histone-binding sites on PfNapS. Extensive sequence and structural comparisons were done with the crystal structures available for NAP/SET family of proteins.

RESULTS

Crystal structure of PfNapS shares structural similarity with previous structures from NAP/SET family. Failed attempts to knock-out the gene for PfNapS from malaria parasite suggest essentiality in the parasite. GFP-fused PfNapS fusion protein targeting indicates cellular localization of PfNapS in the parasite nucleus. Fluorescence spectroscopy data suggest that PfNapS interacts with core histones (tetramer, octamer, H3, H4, H2A and H2B) at a different site from its interaction with linker histone H1. This analysis illustrates two regions on the PfNapS dimer as the possible sites for histone recognition.

CONCLUSIONS

This work presents a thorough analysis of the structural, functional and regulatory attributes of PfNapS from P. falciparum with respect to previously studied histone chaperones.

Cystojejunostomy for non-parasitic hepatic cyst with biliary communication

Non-parasitic hepatic cysts containing bile are rare entities and pose a challenge in surgical management as they cannot be managed by simple de-roofing. The biliary communication to the cyst cavity should either be closed meticulously, or these cysts should be managed by an internal drainage procedure such as cystoenterostomy. We report a 17-year-old Indian girl, in which such a cyst was treated by cystojejunostomy.

M-01ZH09, an oral live attenuated Salmonella enterica serovar Typhi vaccine for the prevention of typhoid fever

Typhoid fever remains a major health problem globally, particularly in the developing world. The increased emergence of several multidrug-resistant strains of Salmonella enterica serovar Typhi has made the management of the disease increasingly difficult. Although vaccines against typhoid fever are available, improvements are desired in dosage, immunogenicity and tolerability. Emergent BioSolutions Inc is developing M-01ZH09, a single-dose oral vaccine against typhoid fever based on an attenuated strain of S enterica serovar Typhi. Several clinical trials have been completed for the vaccine, including large phase II trials in the US and Vietnam. Additionally, a phase IIc clinical trial was ongoing in India at the time of publication. The available data suggest that M-01ZH09 is well tolerated in clinical trials, and is highly immunogenic, provoking broad immune responses. Because M-01ZH09 involves administration as a single oral dose, the vaccine has the potential to be used in a mass immunization program.

CYP11B2 gene haplotypes independently and in concurrence with aldosterone and aldosterone to renin ratio increase the risk of hypertension

OBJECTIVES

Aldosterone synthase produces aldosterone, which regulates electrolytes and thereby blood pressure. Polymorphisms in aldosterone-synthase gene (CYP11B2) may associate with heterogeneous aldosterone production and hypertension. Hence, we investigated -344T/C, Iw/Ic polymorphisms of CYP11B2, plasma renin activity (PRA) and aldosterone concentration (PAC).

DESIGN AND METHODS

Consecutive ethnically-matched 450 hypertensive patients and 360 controls were screened by PCR-RFLP for genotypes and haplotypes; PRA and PAC were measured.

RESULTS

The Iw/Ic polymorphism distribution differed significantly between the two groups (LRT chi(2)=15.8, df=2, P=0.000). The mutant allele-Ic and genotype-Ic/Ic were overrepresented in patients (35% versus 27% and 13% versus 7%). Overrepresentation of T-Ic haplotype in patients was identified as risk haplotype (P=0.000). Patients had significantly higher PAC and aldosterone-to-renin ratio (ARR; P=0.000), which was Ic-allele dependent.

CONCLUSIONS

The haplotype T-Ic associated with hypertension susceptibility. Correlation between Ic-allele and raised ARR likely serve in hypertension management.

Polyelectrolyte coated multilayered liposomes (nanocapsules) for the treatment of Helicobacter pylori infection

Helicobacter pylori infection is one of the major causes of gastric cancers. A number of systems have already been reported, but 100% eradication has never been achieved. The present invention designs a gastro-retentive drug delivery system incorporated with amoxicillin and metronidazole, specifically suited for the eradication of Helicobacter pylori infections due to its mucoadhesiveness in the presence of polyelectrolyte polymers. The system possesses the advantages of both vesicular and particulate carriers, and it was prepared by alternative coating of polyanion (poly(acrylic acid), PAA) and polycation (poly(allylamine hydrochloride), PAH) using liposomes as the core. Compared with the conventional liposomes, the polyelectrolyte based multilayered system (nanocapsules) gave prolonged drug release in simulated gastric fluid, which is well suited for drug delivery against H. pylori infection in the stomach. In vitro growth inhibition study, agglutination assay, and in situ adherence assay in cultured H. pylori suggested the successful in vitro activity and binding propensity of the system. In vivo bacterial clearance study carried out in a H. pylori infected mouse model finally confirmed the success of the developed novel nanocapsule system. Thus, the newly developed composite nanocapsules along with the use of combination therapy proved to have commendable potential in Helicobacter pylori eradication as compared to already existing conventional and novel drug delivery systems.

Emergence of Virulence to Sr25 of Puccinia graminis f. sp. tritici on Wheat in India

Stem (black) rust, caused by Puccinia graminis Pers. f. sp. tritici Eriks. & Henn., is one of the most destructive diseases of wheat. It could be controlled through introgression of race-specific resistance genes. However, such kind of resistance is mostly short lived due to emergence of new virulences. For example, resistance genes Sr11, Sr24, Sr30, and Sr31 are no longer effective (2,4). Detection of new virulences has remained vital in the evaluation and identification of new sources of resistance. We report here the detection of virulence to Sr25, a gene from Thinopyrum elongatum (4), which had been effective or partially effective against stem rust worldwide, including race Ug99 (TTKSK) (4). A stem rust isolate collected in 2006 from Karnataka (southern India) produced susceptible reactions (infection type [IT] 3+ to 4) on the primary leaves of differential genotype 'Agatha' carrying Sr25 and susceptible check 'Agra Local' at 22 ± 2°C. To verify virulence to Sr25, single-pustule isolates from this sample were inoculated onto seedlings of 'Agrus', 'Agatha', 'RL6040' ('Thatcher' + Sr25), 'Superseri#1', 'Wheatear', and 'Morocco' + Sr25 (obtained from CIMMYT), which all carry Sr25. All these accessions were found susceptible (IT 3+ to 4) to this isolate, except Wheatear which expressed resistance (IT ;1), indicating the presence of additional gene(s). These genotypes are resistant (ITs ;1 to 2+) to Sr25-avirulent pathotypes. The new pathotype is avirulent to Sr11, 13, 14, 21, 22, 23, 24, 26, 27, 29, 31, 32, 33, 35, 37, 38, 39, 40, 43, and Tmp and virulent to Sr5, 6, 7a, 7b, 8a, 9a, 9b, 9d, 9e, 9f, 9g, 10, 12, 15, 16, 17, 18, 19, 20, 25, 28, 30, 34, 36, 42, Wld-1, and Gt at 22 ± 2°C. This pathotype has been designated as 58G13-3 and PKTSC according to the Indian nomenclature (1) and the North American system (3), respectively. It represents race 40 based on Stakman's differentials. It may have arisen from race 40 through mutation. The type culture of the pathotype has been added to the culture collection at Flowerdale, Shimla. Interestingly, 'Festiguay' (Sr30) was found resistant to this pathotype, indicating the presence of additional gene(s), whereas 'Webster' (Sr30) was susceptible. Adult plants of Agrus, Agatha, RL6040, Superseri#1, and Morocco+Sr25 also were susceptible, producing 20S to 60S responses. Sr25-avirulent pathotype 62G29 produced a TR (flecking in traces) response on these lines except Morocco + Sr25 that showed 20 to 40MR (moderately resistant) responses. In the same study however, adult plants of Thatcher showed a resistant reaction (10R to MR) at low (16 ± 2°C) and susceptible (20S) at high (22 ± 2°C) temperatures. Agatha and RL6040, having Thatcher as one of the parents, had similar responses. The detection of Sr25 virulence is significant since Sr25 is an important gene to be targeted for breeding wheat cultivars resistant to Ug99. We should use either adult plant resistance and/or pyramiding two or more genes for seedling resistance to enhance the field life of wheat cultivars. References: (1) P. Bahadur et al. Proc. Indian Acad. Sci. 95:29, 1985. (2) S. C. Bhardwaj et al. J. Wheat Res. 1:51, 2007. (3) Y. Jin et al. Plant Dis. 92:923, 2008. (4) R. P. Singh et al. CAB Rev. No. 054:1, 2006.

Molecular variants of HPV-16 associated with cervical cancer in Indian population

Human papilloma virus is a causative factor in the etiology of cervical cancer with HPV16 being the most prevalent genotype associated with it. Intratype variations in oncogenic E6/E7 and capsid L1 proteins of HPV 16 besides being of phylogenetic importance, are associated with risk of viral persistence and progression. The objective of this multicentric study was to identify HPV-16 E6, E7 and L1 variants prevalent in India and their possible biological effects. Squamous cell cervical cancer biopsies were collected from 6 centres in India and examined for the presence of HPV 16. Variants of HPV-16 were characterized by full length sequence analysis of L1, E6 and E7 genes in 412 samples. Similar distribution of the variants was seen from the different centres/regions, with the European variant E350G being the most prevalent (58%), followed by American Asian variant (11.4%). Fifty six changes were seen in E6 region, 31 being nonsynonymous. The most frequent being L83V (72.3%), Q14H (13.1%) and H78Y (12.1%). Twenty-nine alterations were seen in E7 region, with 12 being nonsynonymous. The most frequent being F57V (9%). L1 region showed 204 changes, of which 67 were nonsynonymous. The most frequent being 448insS (100%), and 465delD (100%), H228D (94%), T292A (85%). The identified variants some new and some already reported can disrupt pentamer formation, transcriptional regulation of the virus, L1 protein interface interaction, B and T cell epitopes, p53 degradation, and thus their distribution is important for development of HPV diagnostics, vaccine, and for therapeutic purpose.

Multi-locus interactions of vascular homeostasis genes in essential hypertension: a gender-based study

BACKGROUND

Studies on genes of endothelial and vascular homeostasis are inadequate in females.

METHODS

We investigated the role of 7 variants of ACE, AGT and NOS3 and their correlation with NO(x) levels and ACE activity in hypertension susceptibility in 910 case-controls of both genders.

RESULTS

Prevalence of alleles D of ACE I/D; -6A of AGT -6G/A; -786C, 894T and 4a of NOS3 -786T/C, 894G/T and 4b/4a polymorphisms was observed in patients (P< or =0.05). The 3 genotypes-combinations containing 6+5 wild-type alleles of AGT and NOS3 were significantly less prevalent in patients (P< or =0.0003). The haplotypes 235T/174T/-6A of AGT (P=4E-3) and -786T/894G/4a and -786C/894G/4a of NOS3 (P=2E-3, P=0.011, respectively) were significantly more prevalent in patients. The AGT and NOS3 findings were similar in males. Genotypes-combinations with 6+5 wild-type alleles of AGT correlated with higher NO(x) levels (P=0.03). The NOS3 genotypes-combinations having 6 and 6+5 wild-type alleles correlated with decreased ACE activity (P=0.025, P=0.0015, respectively) and increased NO(x) levels (P=0.001, P=0.0001, respectively) in patients. In gene-gene interactions, ACE D allele associated with < or =4 wild-type alleles containing genotypes-combinations of AGT and NOS3 in patients (P< or =0.04).

CONCLUSION

Within gene and between genes interactions of variants influence ACE activity and NO(x) levels and associate with EH.

Crystal structure of malaria parasite nucleosome assembly protein: distinct modes of protein localization and histone recognition

Nucleosome assembly proteins (NAPs) are histone chaperones that are essential for the transfer and incorporation of histones into nucleosomes. NAPs participate in assembly and disassembly of nucleosomes and in chromatin structure organization. Human malaria parasite Plasmodium falciparum contains two nucleosome assembly proteins termed PfNapL and PfNapS. To gain structural insights into the mechanism of NAPs, we have determined and analyzed the crystal structure of PfNapL at 2.3 A resolution. PfNapL, an ortholog of eukaryotic NAPs, is dimeric in nature and adopts a characteristic fold seen previously for yeast NAP-1 and Vps75 and for human SET/TAF-1b (beta)/INHAT. The PfNapL monomer is comprised of domain I, containing a dimerization alpha-helix, and a domain II, composed of alpha-helices and a beta-subdomain. Structural comparisons reveal that the "accessory domain," which is inserted between the domain I and domain II in yeast NAP-1 and other eukaryotic NAPs, is surprisingly absent in PfNapL. Expression of green fluorescent protein-tagged PfNapL confirmed its exclusive localization to the parasite cytoplasm. Attempts to disrupt the PfNapL gene were not successful, indicating its essential role for the malaria parasite. A detailed analysis of PfNapL structure suggests unique histone binding properties. The crucial structural differences observed between parasite and yeast NAPs shed light on possible new modes of histone recognition by nucleosome assembly proteins.

Inflammatory response to isocyanates and onset of genomic instability in cultured human lung fibroblasts

Lungs comprise the primary organ exposed to environmental toxic chemicals, resulting in diverse respiratory ailments and other disorders, including carcinogenesis. Carcinogenesis is a multi-stage phenomenon, which involves a series of genetic alterations that begin with genomic instability provoked by certain factors such as inflammation and DNA damage and end with the development of cancer. Isocyanates such as methyl isocyanate are the chief metabolic intermediates in many industrial settings with diverse applications; exposure to them can lead to severe hypersensitive, mutagenic and genotoxic alterations. We examined the molecular mechanisms underlying isocyanate-mediated inflammatory responses and their probable role in the onset of genomic instability in cultured IMR-90 human lung fibroblasts. The isocyanates induced inflammation, resulting in extensive DNA damage, evidenced by increases in ATM, ATR, gammaH2AX, and p53 expression levels. The apoptotic index also increased. Chromosomal anomalies in treated cells included over-expression of centrosome protein and variable amplification of inter-simple sequence repeats, further demonstrating isocyanate-induced genomic instability. This information could be useful in the design of new approaches for risk assessment of potential industrial disasters.

Nitrate removal using Brevundimonas diminuta MTCC 8486 from ground water

Brevundimonas diminuta MTCC 8486, isolated from marine soil of coastal area of Trivandrum, Kerala, was used for biological removal of nitrate from ground water collected from Kar village of Pali district, Rajasthan. The organism was found to be resistance for nitrate up to 10,000 mg L(-1). The optimum growth conditions for biological removal of nitrate were established in batch culture. The effect of carbon sources on nitrate removal was investigated using mineral salt medium (MSM) containing 500 mg L(-1) of nitrate to select the most effective carbon source. Among glucose and starch as carbon source, glucose at 1% concentration increased the growth (182+/-8.24 x 10(4) CFU mL(-1)) and induced maximum nitrate reduction (86.4%) at 72 h. The ground water collected from Kar village, Pali district of Rajasthan containing 460+/-5.92 mg L(-1) of nitrate was subjected to three different treatment processes in pilot scale (T1 to T3). Higher removal of nitrate was observed in T2 process (88%) supplemented with 1% glucose. The system was scaled up to 10 L pilot scale treatment plant. At 72 h the nitrate removal was observed to be 95% in pilot scale plant. The residual nitrate level (23+/-0.41 mg L(-1)) in pilot scale treatment process was found to be below the permissible limit of WHO.

Anti-Salmonella activity of Terminalia belerica: in vitro and in vivo studies

To search for an herbal remedy for protection against and treatment for typhoid fever, a number of plants were screened. Anti-Salmonella activity of Terminalia belerica, an ingredient of Ayurvedic preparation 'triphala' used for treatment of digestive and liver disorders, has been reported. Fruits of T. belerica were extracted with petroleum ether, chloroform, acetone, alcohol and water and efficacy of extracts against Salmonella typhi and Salmonella typhimurium was evaluated. Alcoholic and water extracts of T. belerica showed significant anti-Salmonella activity and MIC was 12.5 mg/ml against S. typhimurium. Aqueous extracts of Picrohiza kurroa and Vitits vinefera also showed low anti-Salmonella activity where as aqueous extracts of Asparagus racemosus and Zingiber officinale showed no anti-Salmonella activity. Extracts of T. belerica, Picrohiza kurroa and Vitits vinefera with other solvents such as chloroform and petroleum ether showed insignificant activity. Results showed that aqueous extract of T. belerica was bactericidal at high concentrations where as low concentrations showed bacteriostatic property. In vitro cellular toxicity studies showed no cyto-toxicity associated with T. belerica extracts. Pretreatment of mice with aqueous extract of T. belerica conferred protection against experimental Salmonellosis and 100% survival of animals has been reported when challenged with lethal doses of S. typhimurium.

Development and Characterization of Mucoadhesive Microspheres Bearing Salbutamol for Nasal Delivery

Mucoadhesive drug delivery systems are those that provide intimate contact of the drug with the mucosa for an extended period of time. In our present work, mucoadhesive chitosan microspheres were prepared by emulsion solvent method. Formulations were characterized for various physicochemical attributes, shape, surface morphology, size, and size distribution, drug payload, swelling ability, and mucoadhesion. The effect of drug, citric acid, and permeation enhancer concentration on the physicochemical properties was studied. Crosslinked chitosan microspheres showed very good mucoadhesion, which was decreased on increasing the drug concentration and citric acid concentration, and slightly improved upon incorporation of permeation enhancer. The in vitro drug release and in vitro drug permeability through mucous membrane were performed, and slow release/permeation was noted with chitosan citrate complexed microspheres compared with noncomplexed chitosan microspheres. The in vivo performance of mucoadhesive microspheres formulations showed prolonged and controlled release of salbutamol as compared with oral administration of conventional dosage form.

Design and Development of Multiparticulate System for Targeted Drug Delivery to Colon

A multiparticulate system combining pH-sensitive property and specific biodegradability for colon-targeted delivery of metronidazole has been investigated. Cross-linked chitosan microspheres were prepared from an emulsion system using liquid paraffin as the external phase and solution of chitosan in acetic acid as the disperse phase. The multiparticulate system was prepared by coating cross-linked chitosan microspheres exploiting Eudragit L-100 and S-100 as pH-sensitive polymers. Morphology and surface characteristics of the formulations were determined by scanning electron microscopy. Particle size of the chitosan microspheres was determined by optical microscopy while that of coated microspheres was determined by particle size analyzer. In vitro drug-release studies were performed in conditions simulating stomach-to-colon transit in presence and absence of rat caecal contents. The size of the microspheres was small and they were efficiently microencapsulated within Eudragit microspheres, forming a multireservoir system. By coating the microspheres with Eudragit pH-dependant release profiles were obtained. No release was observed at acidic pH; however, when it reached the pH where Eudragit starts solublizing there was continuous release of drug from the formulation. Further, the release of drug was found to be higher in the presence of rat caecal contents, indicating the susceptibility of chitosan matrix to colonic enzymes released from rat caecal contents.

Polysaccharides for Colon Targeted Drug Delivery

Colon targeted drug delivery has the potential to deliver bioactive agents for the treatment of a variety of colonic diseases and to deliver proteins and peptides to the colon for their systemic absorption. Various strategies, currently available to target the release of drugs to colon, include formation of prodrug, coating of pH-sensitive polymers, use of colon-specific biodegradable polymers, timed released systems, osmotic systems, and pressure controlled drug delivery systems. Among the different approaches to achieve targeted drug release to the colon, the use of polymers especially biodegradable by colonic bacteria holds great promise. Polysaccharidases are bacterial enzymes that are available in sufficient quantity to be exploited in colon targeting of drugs. Based on this approach, various polysaccharides have been investigated for colon-specific drug release. These polysaccharides include pectin, guar gum, amylose, inulin, dextran, chitosan, and chondroitin sulphate. This family of natural polymers has an appeal to drug delivery as it is comprised of polymers with a large number of derivatizable groups, a wide range of molecular weights, varying chemical compositions, and, for the most part, low toxicity and biodegradability yet high stability. The most favorable property of these materials is their approval as pharmaceutical excipients.

Development of Matrix-Membrane Transdermal Drug Delivery System for Atenolol

A polymer matrix system for transdermal delivery of Atenolol was developed for its prolonged and controlled release systemic availability. To achieve the desired and controlled release rate, different combinations of Eudragit RL with polyvinyl pyrrolidone and polyethylene glycol 4000 were used in the preparations of polymeric matrix system. These preparations were evaluated for in vitro release and permeation of the drug across pig skin. The desired systems exhibited linear relationship between drug release (Q) versus ne0.8(hr0.8). The product exhibiting required skin permeation 64 mcg/h/cm2 to achieve an effective plasma concentration was selected for the in vivo performance evaluation. The drug plasma profile was compared with the plasma profile obtained following the administration of a conventional oral dose of Atenolol. The study revealed that the designed polymeric matrix transdermal drug delivery system of Atenolol could be successful with improved performance.

Methotrexate bearing calcium pectinate microspheres: a platform to achieve colon-specific drug release

In the present work calcium pectinate (Ca-pectinate) microspheres were prepared to deliver methotrexate in the environment of colon. Calcium pectinate microspheres were prepared by modified emulsification method using calcium chloride as cross linker. All the formulations were evaluated for various physicochemical parameters. Particle size of the microspheres was determined using laser diffraction particle size analyzer. Encapsulation efficiency was determined by digesting with enzyme pectinase for 24 hours and swellability by equilibrium swelling in simulated gastrointestinal fluid. The in vitro drug release studies were performed in simulated gastric fluid for 2 hours and simulated intestinal fluid for 3 hours. In vitro release rate studies were also carried out in simulated colonic fluid in presence of rat caecal contents. Moreover, release rate studies were also carried out after enzyme induction by treating the rats with 1 ml of 1% w/v aqueous dispersion of pectin for 7 days. Mean particle size of the microspheres was found to be in the range of 20.82+/-1.34 to 32.26+/-1.59 microm whereas the entrapment efficiency varied from 52.28+/-0.32 to 74.01+/-3.32%. The in vitro drug release studies in simulated gastric fluid and simulated intestinal fluid showed that only 8.15+/-0.49% drug was released in 5 hours whereas most of the loaded drug was released in simulated colonic fluid containing pectinase. In vitro release rate study showed release of 69.94+/-3.46% of drug in presence of 3% rat caecal contents, which was further increased to 94.43+/-4.48% when enzyme induction was carried out for 7 days. Thus, it is concluded that calcium pectinate microspheres can be used to effectively localize the release of drug in the physiological environment of colon.

Transdermal atenolol releasing system: An approach towards its development

A polymer matrix system for transdermal delivery of atenolol was developed for its prolonged and controlled release using different ratios of ethylcellulose and hydroxypropyl methylcellulose. These polymeric matrix films were characterized for thickness, tensile strength, moisture content and drug content. They were also studied for in vitro drug release and in vitro drug skin permeation. The drug release from the films was found to be Fickian diffusion type and exhibiting linear relationship between drug release (Q) vs. square root of time (t0.5). The in vitro skin permeation of drug from transdermal drug delivery system (TDDS) was evaluated using dermatomed pig skin. The product which shows in vitro drug skin permeation near to 64 mcg/h/ml was selected for in vivo studies. The in vivo studies revealed that Ma EC HPMC 46 is most effective among the other polymeric matrix TDDS. The AUC0-28 with Ma EC HPMC 46 was better than orally administered conventional doses at twelve hours interval (AUC0-28 1587 ng h/ml) as well as no trough and peaks in drug plasma level was recorded with TDDS. Hence, it could be concluded that the designed polymeric matrix TDDS of atenolol could be used successfully for effective and prolonged delivery of atenolol. However, it further demands exploration in clinic, an insight vision towards the development of TDDS for commercial use.

Transferrin coupled liposomes as drug delivery carriers for brain targeting of 5-florouracil

Diseases and disorders of the brain are extremely difficult to treat pharmacologically because most drugs are unable to pass across the blood--brain barriers. Complex multi-strand tight junctions between adjacent cerebral endothelial cells and between choroid plexus epithelial cells form a physical barrier and prevent the passage of water soluble drugs from the blood into the brain, whereas the inward passage of lipid soluble drugs is restricted by drug efflux pumps which act as a functional barrier. In the present work, a transferrin-coupled liposomal system for brain delivery of 5-florouracil has been investigated.5-florouracil and (99m)Tc-DTPA bearing non-coupled liposomes were prepared by cast film method, which were coupled with the transferrin by incubating these liposomes with transferrin in the presence of the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride in saline phosphate buffer (pH 7.4). These liposomal systems were characterized for vesicle size, percent drug entrapment, and in vitro drug release. The size of the liposomes was increased on coupling with transferrin while percent drug entrapment reduced. The results of the in vitro release profile demonstrated that non-coupled liposomal formulation releases a comparatively higher percent (i.e. 74.8+/-3.21%) of drug than coupled liposomes. Results of in vivo study suggested a selective uptake of the transferrin-coupled liposomes from the brain capillary endothelial cells. In case of coupled liposomes, the level of radioactivity was 17-fold more as compared to the free radioactive agent and 13 times more with the non-coupled liposomes. Therefore, it could be concluded that using transferrin coupled liposomes the brain uptake of the drug could be enhanced.

Potential of Guar Gum Microspheres for Target Specific Drug Release to Colon

Various approaches for colon targeted drug delivery have been studied over the last decade including, pro-drugs, timed-released systems, coating of pH-dependant polymer and the use of polysaccharides. In the present work, a novel formulation consisting of cross-linked microspheres of guar gum has been investigated for colon-targeted delivery of metronidazole. An emulsification method involving the dispersion of aqueous solution of guar gum in castor oil was used to prepare spherical microspheres. Process parameters were analyzed in order to optimize the formulation. Shape and surface morphology of the microspheres were examined using scanning electron microscopy. Placebo microspheres exhibited a smooth surface while the incorporation of drug imparted a slight roughness to the surface texture. Particle size of the microspheres was determined using laser diffraction particle size analyzer. The in vitro drug release studies were performed in simulated gastric fluid for 2 h and intestinal fluid for 3 h, which revealed that the drug was retained comfortably inside the microspheres and that only 15.27+/-0.56% of the drug was released in 5 h. In vitro release rate studies were also carried out in simulated colonic fluid (SCF) in the presence of rat cecal contents, which showed improved drug release. Moreover, to induce the enzymes that specifically act on guar gum, the rats were treated with 1 ml of 1% w/v dispersion of guar gum for 2, 4 and 6 days and release rate studies were repeated in SCF in the presence of 2 and 4% w/v of cecal matter. A marked improvement in the drug release was observed in presence of cecal matter obtained after induction when compared to those without induction. In vitro release studies exhibited 31.23+/-1.49% drug release in 24 h in dissolution medium without rat cecal matter. However, the incorporation of 4% w/v cecal matter obtained after 6 days of enzymes induction increased the drug release to 96.24+/-4.77%.

The role of antibiotic prophylaxis in mesh repair of primary inguinal hernias using prolene hernia system: a randomized prospective double-blind control trial

Antibiotic prophylaxis is being commonly used in mesh repair of inguinal hernia but its role has been questioned in a recent Cochrane analysis performed in 2003. Routine use of antibiotic prophylaxis in mesh repair of inguinal hernia can lead to bacterial resistance and increase in cost. In a present double-blind placebo controlled trial involving 120 patients undergoing inguinal hernia repair using prolene hernia system, we did not find any benefit of the routine use of antibiotic prophylaxis in terms of wound infection rate.

Transferrin-conjugated liposomal system for improved delivery of 5-fluorouracil to brain

The objective of this study is to achieve the enhanced delivery of 5-fluorouracil to brain through transferrin-coupled liposomes. 5-Fluorouracil-loaded liposomes were prepared by cast film method and characterized for particle size, shape, percent encapsulation efficiency and in vitro drug release. Biodistribution studies were carried out with the help of radiolabelled 5-fluorouracil. 5-Fluorouracil was labelled with (99m)Tc-DTPA by oxidation-reduction method using stannous chloride and optimized for labelling parameters to get a high labelling efficiency. The in vitro stability was determined to check the efficiency of a system to find out the suitability of the radiolabelled system for in vivo studies. (99m)Tc-DTPA-labelled 5-fluorouracil bearing non-coupled and coupled liposomes were administered intravenously and biodistribution studies were performed. The distribution of 5-fluorouracil via non-coupled and coupled liposomes was determined in various organs, such as lungs, liver, kidneys, spleen and brain, by measuring the radioactivity using a gamma scintillation unit. The results of in vivo studies confirmed a selective uptake of the transferrin-coupled liposomes from the brain capillary endothelial cells. An average of 10-fold increase in the brain uptake of the drug was observed after the liposomal delivery of 5-fluorouracil, while the transferrin-coupled liposomes caused a 17-fold increase in the brain uptake of 5-fluorouracil. Therefore, it can be concluded that transferrin-coupled liposomes enhance the brain uptake of the drug, like 5-fluorouracil.

Role of cyanoacrylate in the management of low fistula in ano: a prospective study

BACKGROUND AND AIMS

Fistulotomy has remained the gold standard in the management of fistula in ano, especially low fistula in ano. Although highly effective in the management of fistula in ano, fistulotomy is associated with considerable discomfort and incontinence. This study was designed to evaluate the role of cyanoacrylate in the management of low fistula in ano. We present our short-term results with a 6-month follow-up.

MATERIALS AND METHODS

Twenty patients were enrolled in the study as day cases. Patients were analyzed clinically and then subjected to trans-anal ultrasound, as diagnosis of internal opening was not palpable on per rectal examination. The fistula tracks were probed and washed with saline, and granulation tissue at external opening was debrided. The glue was then injected into the fistulous track from a syringe nozzle through an infant feeding tube. Patients were further examined in the outpatient department until 6 months.

RESULTS

Seventeen patients got healed with primary injection with stoppage of any discharge from the fistulous track. The other two patients required one more injection and showed no signs of discharge thereafter. One patient who had two external openings continued to discharge from one opening even after two injections.

CONCLUSIONS

Cyanoacrylate glue can be offered as an effective alternative to surgery in patients suffering from fistula in ano as it is easy, safe, non-invasive, and effective.

Optimized conditions for high-level expression and purification of recombinant human interleukin-2 in E. coli

Interleukin-2 (IL-2), a potent cytokine has been used in anti-cancer therapy for over a decade now. IL-2, originally identified as a growth factor for T lymphocytes is a 15 kDa hydrophobic glycoprotein that induces the activation, clonal proliferation and differentiation of T and B-lymphocytes and enhances the cytotoxicity of monocytes and natural killer (NK) cells. Here, we report a simple method for the cloning, high-level expression and purification of IL-2 protein, which can be easily extended to other bioactive therapeutic proteins. The IL-2 gene was amplified from human spleen cDNA and cloned in a prokaryotic (E. coli) expression system. An optimal expression of the IL-2 protein was determined by varying the expression conditions like temperature, inducer concentration and duration of induction. The protein was expressed as inclusion bodies and a panel of reagents including detergents, urea and guanidine hydrochloride were used to solubilize it. After solubilization, the protein was renatured and subjected to a single step gel-filtration chromatography to yield immunobioactive IL-2 protein with > 99% purity.

Design and development of a mucoadhesive buccal film bearing progesterone

The purpose of this research was to develop and evaluate mucoadhesive films for buccal administration of progesterone using film-forming and mucoadhesive polymers. Buccal films of chitosan bearing progesterone were prepared by solvent casting technique. The films have been evaluated in terms of film weight, thickness, density, surface pH, FT-IR, X-ray diffraction analysis, bioadhesion, swelling properties, in vitro drug release and in vivo studies. It was found that the film formulations of 2 cm2 size having weight in the range of 239 +/- 0.32 to 290 +/- 3.23 mg and film thickness were in the range of 0.49 +/- 0.21 to 0.60 +/- 0.26 mm. Density of the films was found to be 0.108 to 0.139 g/mL. Drug content was found to be uniform in a range of 9.21 +/- 0.051 to 9.67 +/- 0.086 mg/cm2 for formulation F1 to F4. Maximum bioadhesion force was recorded for PVP buccal films (formulation F2) i.e. 0.45 +/- 0.53 N as compared to other films. In vitro residence time was in range of 1.85 +/- 0.08 to 8.94 +/- 0.08 h. The drug release studies revealed that formulations follows non-fickian diffusion. In vivo residence time data confirmed that none of the polymers detached from the oral mucosa over the study period, which indicated that the bioadhesion values of all polymers were satisfactory to retain the film on the buccal mucosa. These mucoadhesive formulations could offer many advantages in comparison to traditional treatments and their efficacy as an effective contraception is assessed.

Bellary, India achieves negligible case fatality due to Japanese encephalitis despite no vaccination: an outbreak investigation in 2004

OBJECTIVE

To confirm the existence of the outbreak of suspected Japanese encephalitis, identify the source, to understand the circumstances due to which the outbreak was taking place and to suggest measures for its control.

METHODS

The team visited Bellary from 4th to 10th Sept, 2004. The team interviewed the key persons and analyzed the records at District Surveillance Unit and Entomological Surveillance Unit and case records of suspected JE cases admitted in Encephalitis ward in Vijay Nagar Institute of Medical Sciences (VIMS). Eco-entomological survey was done in houses and surroundings of 3 randomly selected cases of Encephalitis in rural and urban areas of District Bellary. Their family members and neighbors were also asked for the awareness and presence of disease. Data was analyzed for epidemiological and clinical profiles.

RESULTS

The suspected JE cases were being reported from end of June 2004. The cases were sporadic and out of 34 cases reported to VIMS (till 10th of September), 32 were from Bellary district and 2 were from adjoining Andhra Pradesh. Among these 32, 22 were from Bellary Taluk, which in turn were mainly concentrated (10 were reported) in urban Bellary. The case fatality rate was zero as no death was reported. Entomological surveillance (done by District Surveillance Unit) revealed a high outdoor presence of Culex tritaeniorhynchus as well as an indoor rising density of this mosquito from 2 per man hour catch in January to 22 in the month of August in the affected villages. On the contrary, the investigations on 7th and 8th September revealed high densities of An.subpictus and An. peditaenatus and nil of Culex species in the urban areas. Amplifier host of pigs and water birds were occasionally sighted in the area.

CONCLUSION

A good community awareness of encephalitis, a prompt referral system and a good supportive treatment for the patients and a good surveillance system and response were observed. Very close proximity with amplifying hosts of pigs was avoided by the community, though piggeries were still not very far away (1-3 Km). These may explain the reduction in cases, deaths and disabilities due to this disease in this district over the years. Possibilities of mutant strain which is less virulent and/or a better immune status of at risk population may also need to be explored. The impact of the mass vaccination with SA 14-14-2, imported from China in Bellary during July, 2006 remains to be evaluated. This will further decrease the case load.

Immunological, cellular and molecular events in typhoid fever

Salmonella, a facultative intracellular Gram-negative bacterium infects a wide range of hosts causing several gastrointestinal diseases and enteric fever in humans and certain animal species. Typhoid caused by Salmonella typhi remains a major health concern in India and worldwide. Also, with emergence of multidrug resistant strains, Salmonella has acquired increased virulence, communicability and survivability, resulting in increased morbidity and mortality. Though a number of vaccines for typhoid are available against S. typhi (or also against S. typhimurium), these have certain undesirable side effects and the search for new immunogens suitable for vaccine formulation is still continuing. The immune response to primary Salmonella infection involves both humoral and cell-mediated responses. The protective immunity against Salmonella depends on host- parasite interaction, however; the detailed mechanism of virulence, innate resistance and susceptibility of host remains unclear. This review focuses on the molecular, immunological and cellular mechanisms of pathogenesis of Salmonella infection to provide an insight to counteract bacterial infections and allow a better understanding of its clinical manifestations. It also reviews better technological possibilities combined with increased knowledge in related fields such as immunology and molecular biology and allow for new vaccination strategies. Some new approaches such as subunit and nucleic acid vaccines and recombinant antigen which are becoming increasingly important for the development of potential vaccines have also been discussed. A significant progress has been made in our understanding of Salmonella pathogenesis. Despite these efforts, however, many challenges exist, especially for investigators who aim to understand how the pathogenic mechanisms operating in vitro apply to in vivo model systems. However, unyielding work and collaborations between Salmonella researchers and clinicians worldwide have made significant contributions to understanding the interaction between virulence determinants and immunity required to stop the spread of this pathogen.

Small amplitude ion-acoustic double layers in multicomponent plasma with positrons

Ion-acoustic double layers has been studied in multicomponent plasma with positrons. Using the reductive perturbation method, the modified Korteweg-de Vries (mKdV) equation is derived for the system. The double-layer solution of the mKdV equation is discussed in detail. It is found that there exist two critical concentrations of positrons, alphaR and alphaQ, which decide the existence and nature of the ion-acoustic double layers. It is also found that the system supports ion-acoustic double layers only when the positron concentration (alpha) is less than the critical concentration alphaR (i.e., alpha<alphaR). It is also investigated that for the given set of parameter values, if alphaR<alphaQ, the system supports only rarefactive double layers for the values of alpha lying in the range 0<alpha<alphaR. However, for the given set of parameter values alphaR>alphaQ, the system supports rarefactive double layers for alpha<alphaQ, and for alpha>alphaQ, compressive double layers exist. The present theory also predicts that for a given set of parameter values on increasing the positron concentration, the amplitude of the rarefactive (compressive) double layer decreases (increases), whereas as positron concentration is increased, the width of the rarefactive (compressive) double layer increases (decreases). The effects of positron concentration and temperature ratio on the characteristics of the double layers (namely amplitude and width) are discussed in detail.

Crossed ectopia of ureters with single ectopic ureteric opening--a rare anomaly

Crossed ectopic position of ureters with a single ectopic ureteric opening is an extremely rare condition with no reported case in indexed publications so far. Embryological explanation of this condition can be by agenesis of the left-side mesonephric duct and ureteric bud due to outpouching from the right ureteric bud joining the left mesonephric blastema at an early stage of development.

Epidemiological investigation of an outbreak of chikungunya in hyderabad and nalgonda districts of andhra pradesh, India

After about three decades, Chikungunya infection has re-emerged in India and the first cases were reported in December, 2005. The outbreak has currently affected about 8 states in the country. Although known to be commonly non fatal, since the present outbreak involved a large population, it has been raised as an issue of public health concern and also attracted wide media attention. The clinico-epidemiological and entomological review of the Chikungunya outbreak situation in Hyderabad and Nalgonda Districts of Andhra Pradesh, which started in December 2005, revealed that it is under control. However, preventive efforts need to continue and disease surveillance for early detection of potential outbreaks further strengthening. Given the significantly high House Index, all the three study areas remain at significant risk of outbreaks in the future if appropriate control measures are not put in place. Community support and participation is also crucial for the prevention of future outbreaks and improving the health and well being of population in the districts.

An evaluation of diarrheal diseases and acute respiratory infections control programmes in a Delhi slum

OBJECTIVE

Effective early management at home level and health seeking behavior in case of appearance of danger signs are key strategies in Acute respiratory Infections (ARI) and Acute Diarrheal Diseases (ADD) where majority of episodes are self-limiting and viral in origin. Integrated Management of Childhood illnesses (IMNCI) also envisages that family and community health practices especially health care seeking behaviors are to be improved to reduce childhood morbidity, mortality and cost of admissions to hospitals. Thus, a study was undertaken at an urban slum area--'Gokul Puri' in Delhi, among under-5 children with the aim to assess the magnitudes of ARI and ADD.

METHODS

A Cross-sectional survey was conducted in this urban slum of Trans-Yamuna, covering 1307 under-5 children for five days starting from 9th of August, 2004. Survey team consisted of 14 FETP Participants (WHO Fellows) from India, Nepal, Myanmar, Bhutan and Sri Lanka. A pre-tested, house-hold tally marking form was used to interview the caretakers/mothers. History of episodes of ARI and/or ADD in the last two weeks was asked. Health care practices including use of ORS &home available fluids in diarrhea, continued feeding during diarrhea, awareness of danger signs of ARI &ADD and medical advice sought were asked of those mothers whose children had such an episode.

RESULTS

191 (14.6 %) of 1307 children surveyed, had an attack of ARI in the preceding two wk. The common symptoms of ARI cases were mild running nose (78%), cough (76.4%) and/or fever (45.5%). Only 8 (4%) had fast breathing. One or more danger signs were known to 80% (152/191) of mothers and an equal number (80%) of mothers had sought treatment. ARIs are mostly mild or self limiting but only 16% of caretakers perceived so and doctors also prescribed medicines. The attack rate of Acute Diarrheal Diseases was 7.73% in the study and ADD's annual adjusted morbidity rate was 1.69 episodes per child per year. Though nearly three-fourth of mothers (71.3%) had reported to be seeking medical advice (which is not needed in mild episodes of diarrhea) the ORS use was 38.6%, use of Home available fluids (HAF) was 42% and continued feeding was 50% during the ADD episode and awareness of at least two danger signs was present in 34%.

CONCLUSION

Though aware of danger signs of ARI, care takers were still seeking medical advice for mild cases of ARI and doctors were prescribing drugs. Correct home based management e.g. use of ORS, continued feeding etc. was deficient in the community. Knowledge of danger symptoms was low and medical advice was being sought and drugs were being prescribed for ADD, too.

Characterization of plasma parameters, first beam results, and status of electron cyclotron resonance source

Electron cyclotron resonance (ECR) plasma source at 50 keV, 30 mA proton current has been designed, fabricated, and assembled. Its plasma study has been done. Plasma chamber was excited with 350 W of microwave power at 2450 MHz, along with nitrogen and hydrogen gases. Microwave power was fed to the plasma chamber through waveguide. Plasma density and electron temperature were studied under various operating conditions, such as magnetic field, gas pressure, and transversal distance. Langmuir probe was used for plasma characterization using current-voltage variation. The nitrogen plasma density calculated was approximately 4.5 x 10(11) cm(-3), and electron temperatures of 3-10 eV (cold) and 45-85 eV (hot) were obtained. The total ion beam current of 2.5 mA was extracted, with two-electrode extraction geometry, at 15 keV beam energy. The optimization of the source is under progress to extract 30 mA proton beam current at 50 keV beam energy, using three-electrode extraction geometry. This source will be used as an injector to continuous wave radio frequency quadrupole, a part of 100 MeV proton linac. The required root-mean-square normalized beam emittance is less than 0.2pi mm mrad. This article presents the study of plasma parameters, first beam results, and status of ECR proton source.

Chikungunya viral disease in district Bhilwara (Rajasthan) India

An investigation of chikungunya outbreak cases was carried out in Bhilwara District, Rajasthan during Aug-Sep 2006. Fever with multiple joint pains was the first presenting feature. Aedes larval surveys indicate high Breteau index (78.6 to 200), House index (48.0 to 83.3) & Container index (41.1 to 73.6) above the critical index. Out of 40 sera samples tested, 12 showed HI antibodies for chikungunya virus in high titres and another five were positive for IgM antibodies against chikungunya. The clinico-epidemiological, laboratory and entomological investigations confirm that this episode of fever was due to chikungunya fever. Strengthening and intensification of surveillance along with educating the community were recommended for control of outbreak.

Freezing of fluids confined in a disordered nanoporous structure

Freezing of a simple fluid in a disordered nanoporous carbon is studied using molecular simulations. Only partial crystallization occurs, and the confined phase is composed of crystalline and amorphous nanodomains. This freezing behavior departs strongly from that for nanopores of simple geometry. We present a method for analyzing the freezing in such disordered materials in terms of a transition in the average size and number of crystalline clusters. The results provide a basis for the interpretation of experiments on freezing in such materials, particularly 1H-NMR and scattering experiments.

Demonstration of uterine receptivity in vitro by co-culture of rat epithelial cells and blastocyst

Uterine receptivity is prerequisite for the attachment of the embryo to the uterine epithelium and involves a specialized polarity-dependent property of uterine epithelial (UE) cells. These UE cells, when polarized in culture, behave like cells in utero by exhibiting apico-basal polarity. In order to develop an implantation model in vitro, UE cells were polarized on extracellular matrix (ECM), and polarity was validated by response to estradiol-17beta administered exogenously. UE cells of pregnant rats at day-3 and day-4 post-coitum (p.c.) and of non-pregnant rats were cultured on bare and extracellular-matrix-coated petri dishes until confluency. Hatched blastocysts were transferred to the cultures, and adhesion was monitored every 24 h. Although blastocysts attached to UE cells that were taken from non-pregnant rats and from rats of day-3 p.c. and cultured on bare plastic, they failed to attach to these cells polarized on ECM. However, blastocysts attached firmly to UE cells that had been taken from rats of day-4 p.c. and polarized on ECM. Receptivity of UE cells taken from non-pregnant and pregnant (day-4 p.c.) rats was quantitated by flow cytometric estimation of cellular levels of beta3 integrin. The expression of beta3 integrin in UE cells from rats of day-4 p.c. was highly significant (P<0.01) when compared with its expression in UE cells from non-pregnant rats. The expression of beta3 integrin in UE cells of day-4 p.c. confirmed the receptivity of these cells to blastocyst implantation. Uterine receptivity was also validated in vivo by inducing the decidual cell reaction in rats ovariectomized on day-3 and day-4 p.c. Whereas remarkable deciduoma was noticed in the animals of day-4 p.c., it was absent in the animals of day-3 p.c., thereby indicating that the uterus was receptive on day-4 p.c. only. Thus, blastocysts do not attach to polarized UE cells that have been obtained from a non-receptive uterus. Attachment will occur only if the cells are obtained from a receptive uterus. UE cell receptivity is therefore essential for mimicking the process of implantation in vitro.

A novel recombinant multiepitope protein as a hepatitis C diagnostic intermediate of high sensitivity and specificity

A novel recombinant multiepitope protein has been designed that consists of six linear, immunodominant, and phylogenetically conserved epitopes from hepatitis C virus. Five of these antigens (core, NS3, NS4I, NS4II, and NS5) are being used in many of the third-generation kits while sixth epitope (core3g) is an additional sequence from a newly identified Indian isolate. The genes for these epitopes have been joined together to code for a single multiepitope protein that has been evaluated for its diagnostic potential for the detection of anti-HCV antibodies in human plasma. Two separate synthetic genes have been designed, both encoding the same six epitopes in a single open reading frame along with spacers having additional amino acids to function as flexible (r-HCV-F-MEP) or rigid (r-HCV-R-MEP) linkers. High-level expression of hepatitis C multiepitope protein in Escherichia coli has been achieved. The protein has been purified using a single affinity step yielding >25 mg pure protein/liter culture and used as the coating antigen in anti-HCV EIA. The use of this multiepitope protein eliminates the requirement for multiple diagnostic intermediates for the development of anti-HCV diagnostic kit. The sensitivity and specificity of the HCV multiepitope protein was evaluated by Boston Biomedica Worldwide Performance Panels, HCV Seroconversion Panels and Viral Co-infection Panels, and was found to be comparable with commercially available anti-HCV EIA kits. This analysis indicated its unequivocal performance as capture antigen in anti-HCV EIA. The high epitope density, careful choice of epitopes and use of E. coli system for expression, coupled with simple purification protocol provides the potential for the development of an inexpensive diagnostic test with high degree of sensitivity and specificity.

Child survival and safe motherhood program in Rajasthan

OBJECTIVE

This study was planned to evaluate the MCH services, particularly immunization in rural areas of the poor-performing state of Rajasthan.

METHODS

A community-based, cross-sectional survey using the WHO 30 cluster technique was carried out as a field exercise by participants of 9th Field Epidemiology Training Programme (FETP) course by National Institute of Communicable Diseases (NICD) in rural areas of Alwar district of Rajasthan.

RESULTS

Less than one third (28.9%) of children, aged 12-23 months, were fully immunized with BCG, 3 DPT, 3 OPV and Measles vaccines; around a quarter (26.5%) had not received even a single vaccine (non immunized), and little less than half (44.5%) were found partially immunized. Around half of the eligible children were vaccinated for BCG (55.9%) and Measles (43.6%). Though nearly two-third (66.8%) were covered with first dose of DPT and OPV, but about one third of these children dropped out of third dose of DPT and OPV for various reasons. National Family Health Survey (NFHS) data also had revealed that BCG coverage was 64.3%; measles was 36.2%; and coverage by DPT 1, 2, 3 and Polio 1,2 and 3 were 64.4%, 57.0%, 46.6% and 77.5%, 71.1% and 54.4% respectively in rural areas. The main reasons for drop-out or non-immunization was "lack of information about the immunization programme" (41.3%). Though nearly all (more than 96%) of the children were immunized through Government established centers, but immunization cards/documents were made available only to 27.6% of children.

CONCLUSION

The problem of low coverage and high drop-out rate of immunization could be overcome by creating awareness of the program and relevance of 2nd and 3rd doses of DPT and polio vaccines. Increasing community participation through intensive and extensive health education campaign should also be undertaken. Since most of the deliveries were done at home under the supervision of untrained midwives, training programme as well as involving them in IEC activities should be contemplated.

An outbreak of dengue fever in Veerannapet village, Cherial Mandal, of Warangal district, Andhra Pradesh

An epidemiological and entomological investigation was carried out in Veerannapet village, Cherial Mandal of Warangal district, Andhra Pradesh. The study showed that all age groups and both the sexes were affected with the disease. Fever and bodyache was the first presenting feature, which was self-limiting and lasted for 4-5 days. Of the 19 Serum Samples tested, 17 showed high titre to Dengue antigen with 10 showing diagnostic titre. Five samples were positive for IgM antibodies to dengue virus. Larval surveys indicates high Breteau index (30.40%), House index (23.20%) and Container index (9.17%). The clinico-epidemiological and entomological investigation indicates present episode of fever outbreak is due to dengue fever. Strengthening and intensification of surveillance along with educating the community is recommended for prevention of outbreak.

Lr19 Resistance in Wheat Becomes Susceptible to Puccinia triticina in India

Lr19, a resistance gene originally transferred from Agropyron elongatum to wheat (Triticum aestivum L.), has remained effective worldwide against leaf rust (Puccinia triticina Eriks.) except in Mexico (1). This report records a new pathotype of P. triticina virulent on Lr19 from India. From 2003 to 2004, 622 wheat leaf rust samples from 14 states were subjected to pathotype analysis. Samples were established on susceptible wheat cv. Agra Local, and pathotypes were identified on three sets of differentials following binomial nomenclature (3). Virulence on Lr19 (Agatha T4 line) was observed in approximately 2% of samples. These samples were picked from Lr19 (NIL), cvs. Ajit, Lal Bahadur, Local Red, Lok1, and Nirbhay from Karnataka and Gujarat states. All Lr19 virulent isolates were identical. The reference culture is being maintained on susceptible wheat cv. Agra Local and has also been put under long-term storage in a national repository at Flowerdale. From 2004 to 2005, this pathotype was detected in 6.3% of samples from central and peninsular India. There is no wheat variety with Lr19 under cultivation in India, however, it is being used in wheat breeding programs targeted at building resistance against leaf and stem rusts. NIL's Lr19/Sr25 (LC25) and Lr19/Sr25 (82.2711) were also susceptible to this isolate, whereas Lr19/Sr25 (spring accession) was resistant. The new isolate, designated as 253R31 (77-8), appears to be close to the pathotype 109R31 (4) with additional virulence for Lr19. The avirulence/virulence formula of pathotype 253R31 is Lr9, 23, 24, 25, 26, 27+31, 28, 29, 32, 36, 39, 41, 42, 43, 45/Lr1, 2a, 2b, 2c, 3, 10, 11, 12, 13, 14a, 14b, 14ab, 15, 16, 17, 18, 20, 21, 22a, 22b, 30, 33, 34, 35, 37, 38, 40, 44, 48, and 49. To our knowledge, this is the first report of virulence on Lr19 from two states of India. On international rust differentials, it is designated as TGTTQ (2), and is different from CBJ/QQ (1), the other isolate reported virulent on Lr19 from Mexico. The Mexican isolate is avirulent on Lr1, 2a, 2b, 2c, 3ka, 16, 21, and 30 to which the Indian isolate is virulent. However, both isolates are avirulent on Lr9, 24, 26, 36, and Lr42. Among the wheat cultivars identified during the last 6 years, HD2824, HD2833, HD2864, HI1500, HS375, HUW 510, HW 2044, HW 5001, Lok 45, MACS 6145, MP4010, NW 2036, PBW 443, PBW 498, PBW 502, PBW 524, Raj 4037, UP 2565, VL 804, VL 829, and VL 832 and lines of wheat possessing Lr9, Lr23, Lr24, and Lr26 showed resistance to this pathotype. PBW 343, which occupies more than 5 million ha in India, is also resistant to this pathotype along with PBW 373. An integrated strategy using a combination of diverse resistance genes, deployment of cultivars by using pathotype distribution data, slow rusting, and adult plant resistance is in place to curtail selection of new pathotypes and prevent rust epiphytotics. References: (1) J. Huerta-Espino and R. P. Singh. Plant Dis. 78:640,1994. (2) D. V. Mc Vey et al. Plant Dis. 88:271, 2004. (3) S. Nagarajan et al. Curr. Sci. 52:413, 1983. (4) S. K. Nayar et al. Curr. Sci. 44:742, 1975.

Skew flap technique in trans-tibial amputation

The long posterior flap technique is an established technique for trans-tibial amputation in ischaemic limbs. Despite its success, it has a few drawbacks. It may be time-consuming and requires considerable planning, and at times the dog-ears cannot be avoided. The suture line passes over the distal end of the stump, which is usually a problem during prosthetic use. The skew flap technique retains the advantages of the long posterior flap technique and eliminates the difficulties of prosthetic fitting. The equal skin flaps are skewed so that the flaps become anteromedial and posterolateral, whereas the calf muscle flap remains long underneath the skewed skin flaps. The posterior muscles are brought anteriorly covering the cut ends of the bones and are buried in between the tibia and its anterior periosteum, by suturing their margins with the periosteum. The skew flap procedure was perceived in 1980 and was started at the Artificial Limb Centre, Pune in 1983 by the author. This procedure underwent many changes during the initial 5 years and by the end of April 1992, 85 trans-tibial amputations were performed using this technique. A 9-year follow-up of these patients, who had been using prostheses with ease and without any discomfort or problem, had been exceptionally good. Encouraged by the results, this technique is now being practised as routinely. By March 1998, a total of 125 such trans-tibial amputations had been performed in 119 patients, with excellent results.