Accumulating candidate genes for broad-spectrum resistance to rice blast in a drought-tolerant rice cultivar.

Biotic stresses, including diseases, severely affect rice production, compromising producers' ability to meet increasing global consumption. Understanding quantitative responses for resistance to diverse pathogens can guide development of reliable molecular markers, which, combined with advanced backcross populations, can accelerate the production of more resistant varieties. A candidate gene (CG) approach was used to accumulate different disease QTL from Moroberekan, a blast-resistant rice variety, into Vandana, a drought-tolerant variety. The advanced backcross progeny were evaluated for resistance to blast and tolerance to drought at five sites in India and the Philippines. Gene-based markers were designed to determine introgression of Moroberekan alleles for 11 CGs into the progeny. Six CGs, coding for chitinase, HSP90, oxalate oxidase, germin-like proteins, peroxidase and thaumatin-like protein, and 21 SSR markers were significantly associated with resistance to blast across screening sites. Multiple lines with different combinations, classes and numbers of CGs were associated with significant levels of race non-specific resistance to rice blast and sheath blight. Overall, the level of resistance effective in multiple locations was proportional to the number of CG alleles accumulated in advanced breeding lines. These disease resistant lines maintained tolerance to drought stress at the reproductive stage under blast disease pressure.

DNA barcoding Indian freshwater fishes.

DNA barcoding is a promising technique for species identification using a short mitochondrial DNA sequence of cytochrome c oxidase I (COI) gene. In the present study, DNA barcodes were generated from 72 species of freshwater fish covering the Orders Cypriniformes, Siluriformes, Perciformes, Synbranchiformes, and Osteoglossiformes representing 50 genera and 19 families. All the samples were collected from diverse sites except the species endemic to a particular location. Species were represented by multiple specimens in the great majority of the barcoded species. A total of 284 COI sequences were generated. After amplification and sequencing of 700 base pair fragment of COI, primers were trimmed which invariably generated a 655 base pair barcode sequence. The average Kimura two-parameter (K2P) distances within-species, genera, families, and orders were 0.40%, 9.60%, 13.10%, and 17.16%, respectively. DNA barcode discriminated congeneric species without any confusion. The study strongly validated the efficiency of COI as an ideal marker for DNA barcoding of Indian freshwater fishes.

Model for the interpretation of nuclear magnetic resonance relaxometry of hydrated porous silicate materials.

Nuclear magnetic resonance (NMR) relaxation experimentation is an effective technique for probing the dynamics of proton spins in porous media, but interpretation requires the application of appropriate spin-diffusion models. Molecular dynamics (MD) simulations of porous silicate-based systems containing a quasi-two-dimensional water-filled pore are presented. The MD simulations suggest that the residency time of the water on the pore surface is in the range 0.03-12 ns, typically 2-5 orders of magnitude less than values determined from fits to experimental NMR measurements using the established surface-layer (SL) diffusion models of Korb and co-workers [Phys. Rev. E 56, 1934 (1997)]. Instead, MD identifies four distinct water layers in a tobermorite-based pore containing surface Ca2+ ions. Three highly structured water layers exist within 1 nm of the surface and the central region of the pore contains a homogeneous region of bulklike water. These regions are referred to as layer 1 and 2 (L1, L2), transition layer (TL), and bulk (B), respectively. Guided by the MD simulations, a two-layer (2L) spin-diffusion NMR relaxation model is proposed comprising two two-dimensional layers of slow- and fast-moving water associated with L2 and layers TL+B, respectively. The 2L model provides an improved fit to NMR relaxation times obtained from cementitious material compared to the SL model, yields diffusion correlation times in the range 18-75 ns and 28-40 ps in good agreement with MD, and resolves the surface residency time discrepancy. The 2L model, coupled with NMR relaxation experimentation, provides a simple yet powerful method of characterizing the dynamical properties of proton-bearing porous silicate-based systems such as porous glasses, cementitious materials, and oil-bearing rocks.

Evaluation of pesticide toxicity at their field recommended doses to honeybees, Apis cerana and A. mellifera through laboratory, semi-field and field studies.

A series of experiments were carried out to determine the acute toxicity of pesticides in the laboratory, toxicity through spray on flowering plants of mustard (Tier II evaluation) and field on both Apis cerana and A. mellifera bees. The overall mortality of honey bees through topical (direct contact) were found significantly higher than that of indirect filter paper contamination assays. Insecticides viz., chlorpyriphos, dichlorvos, malathion, profenofos, monocrotophos and deltamethrin when exposed directly or indirectly at their field recommended doses caused very high mortality up to 100% to both the bees at 48 HAT. The insecticides that caused less mortality through filter paper contamination viz., flubendiamide, methyl demeton, imidacloprid and thiamethoxam caused very high morality through direct exposure. Apart from all the fungicides tested, carbendazim, mancozeb, chlorothalonil and propiconazole, insecticides acetamiprid and endosulfan were found safer to both the bees either by direct or indirect exposures. Tier II evaluation by spray of pesticides at their field recommended doses on potted mustard plants showed monocrotophos as the highly toxic insecticide with 100% mortality even with 1h of exposure followed by thiamethoxam, dichlorvos, profenofos and chlorpyriphos which are not to be recommended for use in pollinator attractive flowering plants. Acetamiprid and endosulfan did not cause any repellent effect on honey bees in the field trials endorse the usage of acetamiprid against sucking pest in flowering plants.

Some critical aspects of FT-IR, TGA, powder XRD, EDAX and SEM studies of calcium oxalate urinary calculi.

Urinary calculi constitute one of the oldest afflictions of humans as well as animals, which are occurring globally. The calculi vary in shape, size and composition, which influence their clinical course. They are usually of the mixed-type with varying percentages of the ingredients. In medical management of urinary calculi, either the nature of calculi is to be known or the exact composition of calculi is required. In the present study, two selected calculi were recovered after surgery from two different patients for detailed examination and investigated by using Fourier-Transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis (TGA), powder X-ray diffraction (XRD), scanning electron microscopy and energy dispersive analysis of X-rays (EDAX) techniques. The study demonstrated that the nature of urinary calculi and presence of major phase in mixed calculi could be identified by FT-IR, TGA and powder XRD, however, the exact content of various elements could be found by EDAX only.

Pre-treatment neutrophil-to-lymphocyte ratio as predictor of adverse outcomes in patients undergoing radical cystectomy for urothelial carcinoma of the bladder.

BACKGROUND: An elevated neutrophil-to-lymphocyte ratio (NLR) is associated with poor outcome in various tumours. Its prognostic utility in patients with urothelial carcinoma of the bladder (UCB) undergoing radical cystectomy (RC) is yet to be fully elucidated. METHODS: A cohort of patients undergoing RC for UCB in a tertiary referral centre between 1992 and 2012 was analysed. Neutrophil-to-lymphocyte ratio was computed using complete blood counts performed pre-RC, or before neo-adjuvant chemotherapy where applicable. Time-dependent receiver operating characteristic curves were used to determine the optimal cutoff point for predicting recurrence-free survival (RFS), cancer-specific survival (CSS) and overall survival (OS). The predictive ability of NLR was assessed using Kaplan-Meier analyses and multivariable Cox proportional hazards models. The likelihood-ratio test was used to determine whether multivariable models were improved by including NLR. RESULTS: The cohort included 424 patients followed for a median of 58.4 months. An NLR of 3 was determined as the optimal cutoff value. Patients with an NLR⩾3.0 had significantly worse survival outcomes (5y-RFS: 53% vs 64%, log-rank P=0.013; 5y-CSS: 57% vs 75%, log-rank P<0.001; 5y-OS: 43% vs 64%, log-rank P<0.001). After adjusting for disease-specific predictors, an NLR ⩾3.0 was significantly associated with worse RFS (HR=1.49; 95% CI=1.12-2.0, P=0.007), CSS (HR=1.88; 95% CI=1.39-2.54, P<0.001) and OS (average HR=1.67; 95% CI=1.17-2.39, P=0.005). The likelihood-ratio test confirmed that prognostic models were improved by including NLR. CONCLUSIONS: Neutrophil-to-lymphocyte ratio is an inexpensive prognostic biomarker for patients undergoing RC for UCB. It offers pre-treatment prognostic value in addition to established prognosticators and may be helpful in guiding treatment decisions.

Development and characterization of a new cell line CF from caudal fin of knifefish, Chitala chitala (Hamilton-Buchanan).

A new cell line was successfully obtained from caudal fin tissue of the economically important freshwater fish Chitala chitala. The cell line was optimally maintained at 28°C in Leibovitz's L-15 supplemented with 20% fetal bovine serum (FBS). The effects of temperature and concentration of FBS on the growth of CF cells were examined. The CF cell line consisted predominantly of fibroblastic-like cells. Moderately low plating efficiencies 8%, 11%, and 17% were observed, with CF cell line in L-15 Medium with 20% FBS. Chromosomal analysis of the cell line revealed a diploid number of 42 chromosomes in C. chitala. Molecular characterization of mitochondrial 16S rRNA and cytochrome oxidase subunit I confirmed the origin of the cell line. The cells were successfully cryopreserved in liquid nitrogen (-196°C) for 6 mo, and more than 85-90% of CF cells were revived.

Nuclear magnetic resonance relaxometry of water in two and quasi-two dimensions.

Molecular dynamics (MD) and Monte Carlo (MC) methods are used to determine the spin-pair correlation function G(*)(t) for the diffusion of bulk water in three dimensions (3D) and pore water in two dimensions (2D) and quasi-two dimensions (Q2D). The correlation function is required for the determination of the nuclear magnetic resonance spin-lattice and spin-spin relaxation times T(1) and T(2). It is shown that the analytic form of the powder-average correlation function, introduced by Sholl [Sholl, J. Phys. C: Solid State Phys. 7, 3378 (1974)] for the diffusion of spins on a 3D lattice, is of general validity. An analytic expression for G(*)(t) for a uniform spin fluid is derived in 2D. An analytic expression for the long-time behavior of G(*)(t) is derived for spins diffusing on 3D, 2D, and Q2D lattices. An analytic correction term, which accounts for spin pairs outside the scope of the numerical simulations, is derived for 3D and 2D and shown to improve the accuracy of the simulations. The contributions to T(1) due to translational and rotational motion obtained from the MD simulation of bulk water at 300 K are 7.4 s and 10±1 s, respectively, at 150 MHz, leading to an overall time of 4.3±0.4 s compared to the experimental value of 3.8 s. In Q2D systems, in which water is confined by alpha-quartz surfaces to thicknesses of 1-5 nm, T(1) for both translational and rotational relaxation is reduced due to the orientation and adsorption of spins at the surfaces. A method of parametrizing the MC lattice-diffusion simulations in 3D, 2D, and Q2D systems is presented. MC results for G(*)(t) for 3D and 2D systems are found to be consistent with an analytic uniform fluid model for t~/>40 ps. The value of TT(1) for translational diffusion obtained from the MC simulation of bulk water is found to be 4.8 s at 15 MHz. G(*)(t) obtained from MC simulations of Q2D systems, where water is confined by hard walls, is found to execute a distinct transition from 3D to 2D behavior. The T(1) is found to be similar to the 3D bulk water result at all pore thicknesses.

Antioxidant properties of different edible mushroom species and increased bioconversion efficiency of Pleurotus eryngii using locally available casing materials.

Total phenolics, radical scavenging activity (RSA) on DPPH, ascorbic acid content and chelating activity on Fe(2+) of Pleurotus citrinopileatus, Pleurotus djamor, Pleurotus eryngii, Pleurotus flabellatus, Pleurotus florida, Pleurotus ostreatus, Pleurotus sajor-caju and Hypsizygus ulmarius have been evaluated. The assayed mushrooms contained 3.94-21.67 mg TAE of phenolics, 13.63-69.67% DPPH scavenging activity, 3.76-6.76 mg ascorbic acid and 60.25-82.7% chelating activity. Principal Component Analysis (PCA) revealed that significantly higher total phenolics, RSA on DPPH and growth/day was present in P. eryngii whereas P. citrinopileatus showed higher ascorbic acid and chelating activity. Agglomerative hierarchical clustering analysis revealed that studied mushroom species fall into two clusters; Cluster I included P. djamor, P. eryngii and P. flabellatus, while Cluster II included H. ulmarius, P. sajor-caju, P. citrinopileatus, P. ostreatus and P. florida. Enhanced yield of P. eryngii was achieved on spent compost casing material. Use of casing materials enhanced yield by 21-107% over non-cased substrate.

Population structure of Tor tor inferred from mitochondrial gene cytochrome b.

Tor tor, commonly called as Tor mahseer, is a high-valued food and game fish endemic to trans-Himalayan region. Mitochondrial cytochrome b (cyt b) gene region of 967 bp was used to estimate the population structure of T. tor. Three populations of T. tor were collected from Narmada (Hosangabad), Ken (Madla), and Parbati river (Sheopur) in Madhya Pradesh, India. The sequence analysis revealed that the nucleotide diversity (π) was low, ranging from 0.000 to 0.0150. Haplotype diversity (h) ranged from 0.000 to 1.000. The analysis of molecular variance analysis indicated significant genetic divergence among the three populations of T. tor. Neighboring-joining tree also showed that all individuals from three populations clustered into three distinct clades. The data generated by cyt b marker revealed interesting insight about population structure of T. tor, which would serve as baseline data for conservation and management of mahseer fishery.

Genetic characterization of two hill stream fish species Barilius bendelisis (Ham.1807) and Barilius barna (Ham.1822) using RAPD markers.

Genetic structure of four wild populations of two hill stream fishes Barilius bendelisis (Ham.1807) and B. barna (Ham. 1822) from Uttarakhand, India, was studied using RAPD markers. Eight selective primers provided distinct and consistent RAPD profiles in both the species, producing a total of 47 and 35 scorable bands in B. bendelisis and B. barna respectively. The bands in the range 666-4,830 bp were scored for consistent results. The RAPD profiles generated by all the eight primers revealed varying degrees of polymorphism (25.00-50.00 %). The average genetic diversity (h) was estimated as 0.1661 and 0.1606 among the four populations of B. bendelisis and B. barna respectively.

Results of antibiotic susceptibility testing do not influence clinical outcome in children with cystic fibrosis.

INTRODUCTION: Patients with CF experience pulmonary exacerbations. These are often initially empirically treated with intravenous antibiotics, with antibiotic choice refined after susceptibility testing. METHODS: We completed a 5-year retrospective review of children attending the Paediatric CF Unit, Nottingham. The respiratory sampling, antibiotic prescribing and susceptibility testing guidance were audited. Episodes were classified according to the concordance between the antibiotics prescribed and antibiotic susceptibility testing. RESULTS: Of 52 patients who had previously isolated Pseudomonas aeruginosa, 103 antibiotic courses were commenced that coincided with an isolation of P. aeruginosa. P. aeruginosa was fully susceptible, partially susceptible or fully resistant on 33%, 44.7% or 16.5% of occasions respectively. The antibiotic prescriptions were never changed following antibiotic susceptibility testing. We found no association between change in FEV(1) (p=0.54), change in BMI (p=0.12) or time to next exacerbation (p=0.66) and concordance between antibiotic susceptibility and the antibiotics administered. CONCLUSION: This study contributes to mounting evidence questioning the utility of routine antibiotic susceptibility testing.

Effect of Withania somnifera on forced swimming test induced immobility in mice and its interaction with various drugs.

The objective of the present study was to evaluate the antidepressant action of Withania somnifera (WS) as well as its interaction with the conventional antidepressant drugs and to delineate the possible mechanism of its antidepressant action using forced swimming model in mice. Effect of different doses of WS, fluoxetine and imipramine were studied on forced swimming test induced mean immobility time (MIT). Moreover effect of WS 100 mg/kg, i.p. was observed at different time intervals. Effect produced by combination of sub therapeutic doses of WS with imipramine (2.5 mg/kg, i.p.) as well as fluoxetine (2.5 mg/kg, i.p.) were also observed. Effect of WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) were observed in mice pretreated with reserpine (2 mg/kg, i.p.) and clonidine (0.15 mg/kg, i.p.). Effects of prazosin (3 mg/kg, i.p.) or haloperidol (0.1 mg/kg, i.p.) pre-treatment were also observed on WS induced decrease in MIT. WS produced dose dependent decrease in MIT. Maximum effect in MIT was observed after 30 min of treatment with WS 100 mg/kg, i.p. Combination of WS (37.5 mg/kg, i.p.) with imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.) also produced significant decrease in the MIT. Clonidine and reserpine induced increase in MIT, was significantly reversed by treatment with WS (100 mg/kg, i.p.) as well as combination of WS (37.5 mg/kg, i.p.) with either imipramine (2.5 mg/kg, i.p.) or fluoxetine (2.5 mg/kg, i.p.). Pre-treatment with prazosin but not haloperidol, significantly antagonized the WS (100 mg/kg, i.p.) induced decrease in MIT. It is concluded that, WS produced significant decrease in MIT in mice which could be mediated partly through a adrenoceptor as well as alteration in the level of central biogenic amines.

An improved urine collection pad method: a randomised clinical trial.

AIM: To evaluate a modified urine collection pad (UCP) method for its ability to reduce heavy mixed growth bacterial contamination of UCP samples in young children with suspected urinary tract infection (UTI). METHOD: Febrile children under 2 years of age were randomised to two UCP METHODS: the same UCP kept in the nappy until urine was passed (single UCP group), or the UCP replaced with a fresh one every 30 minutes until urine was passed (replaced UCP group). In both groups a moisture sensitive audio alarm was used to signal passage of urine. RESULTS: Eighty children were enrolled and a satisfactory sample was obtained in 68 (37 in the single UCP group and 31 in the replaced UCP group). In 12 children (15%), collection failed, mainly because of faecal soiling of the pad. UTI occurred in three children (4%). In the remaining 65 samples, heavy mixed growth (> 10(5) organisms/ml) occurred in 1/31 (3%) in the replaced UCP group compared with 10/35 (29%) in the single UCP group (p = 0.008). There were no adverse effects from the use of the moisture sensitive audio alarm. CONCLUSION: Changing the UCP every 30 minutes almost eliminates heavy mixed growth contamination of UCP samples and substantially increases the proportion of UCP results that confidently exclude UTI. This represents a simple and clinically important improvement to the UCP method which is reliable for diagnosing and excluding UTI in young children still in nappies. It has potential for use in outpatient clinics, in the primary healthcare setting, or at home.

Water temperature and pH influence olfactory sensitivity to pre-ovulatory and post-ovulatory ovarian pheromones in male Barilius bendelisis.

The attractive response and sexual activity elicited by pre-ovulatory steroid sulphate and post-ovulatory 15K-PGF pheromones are greater in wild caught tubercular males and immature males which express breeding tubercles on the snout (at 12-13 days post androgen implant) than in non-tubercular and non-androgen implanted males of freshwater fish Barilius bendelisis. This shows that circulatory androgens exert an activational effect on olfactory receptors of male fish. Wild caught tubercular males and androgen implanted juvenile males exhibit a high responsiveness to steroid sulphate at the water temperature and pH which fish experience during the pre-spawning phase. The male's sensitivity to 15K-PGF is almost equally high at the water temperature and pH which they experience in wild during the both pre-spawning and spawning periods. This suggests that the differential olfactory sensitivity to the two classes of pheromones in androgen implanted males is due to the varied temperature and pH of water, and that during the breeding season the male's olfactory sensitivity to PGF pheromone is more widespread than to the steroidal pheromone. An increased and decreased olfactory sensitivity in mature males to sex pheromones and L-alanine respectively during the breeding phase is in agreement with the hypothesis that pheromonal stimuli dominate over feeding stimuli to promote spawning success.

Ovarian steroid sulphate functions as priming pheromone in male Barilius bendelisis (Ham.).

The study reveals that pre-ovulatory females of the fish Barilius bendelisis (Ham.) release sex steroids and their conjugates into the water and that a steroid sulphate of these compounds functions as a potent sex pheromone which stimulates milt production in conspecific males prior to spawning. Since males exposed to the purified subfraction III of the steroid sulphate fraction have increased milt volume and more spermatozoa with greater motility, the function of this priming pheromone appears to be to enhance male spawning success. High turbulence and faster water currents render the hillstream ecosystem extremely challenging for chemical communication. Therefore, ovulatory female fish secrete highly water soluble steroid sulphates for rapid pheromonal action in males. Inhibited milt volume in olfactory tract lesioned (OTL) males exposed to the steroid sulphate fraction and 17alpha,20 beta-dihydroxy-4-pregnen-3-one supports the concept that the pheromonally induced priming effect in male fish is mediated through olfactory pathways.

Laparoscopic cholecystectomy at the Aga Khan Hospital, Nairobi.

OBJECTIVE: To evaluate our experience of laparoscopic cholecystectomies at the Aga Khan Hospital, Nairobi over a three-year period from the inception of the technique, and to assess its value and advantages to the patients. DESIGN: A prospective case series study. SETTING: The Aga Khan Hospital, Nairobi. PATIENTS: One hundred and thirty five cases operated from February 1996 to April 1999. All patients were subjected to the American method of laparoscopic cholecystectomy, which is described in detail in this paper. MAIN OUTCOME MEASURES: Clinical presentation, age and sex demographics, average hospital stay, intraoperative and postoperative complications and outcome. RESULTS: There was a female preponderance with a female to male ratio of 5:1. Mean age was forty nine years. Majority of patients suffered from chronic cholecystitis. The conversion rate to an open procedure was five per cent. There were two cases of significant bile leakage which required laparotomy. No mortality was reported in this series. CONCLUSION: This technique was found to have distinct advantages such as shorter hospital stay, lesser postoperative pain and very good cosmesis. It is a safe procedure if performed by a well trained surgeon.

Comparative study of beta-adrenoceptor blocking efficacy of two formulations of esmolol in vivo and in vitro.

The objective of the present study was to compare the cardiovascular beta-blocking activity of two different formulations of esmolol. Spontaneously beating guinea-pig isolated atria and the heart rate and blood pressure of anaesthetized cat were employed in the study to compare the beta-blocking efficacy of the two formulations of esmolol using isoprenaline as an agonist. In guinea-pig isolated atria the standard esmolol formulation (Brevibloc) reduced basal atrial rate more significantly than the indigenously formulated esmolol (test formulation). Both the formulations produced similar parallel rightward shift of cumulative concentration response curves of isoprenaline with closely comparable pA2 values. In anaesthetized cats, only indigenous esmolol formulation significantly decreased basal heart rate. Both the formulations did not modify the basal blood pressure and isoprenaline-induced fall in blood pressure, despite significantly blocking isoprenaline-induced tachycardia. It is suggested that both the formulations produced similar degree of beta-1 adrenoceptor blocking activity.