A complete genetic linkage map and QTL analyses for bast fibre quality traits, yield and yield components in jute (Corchorus olitorius L.)

We report the first complete microsatellite genetic map of jute (Corchorus olitorius L.; 2n = 2x = 14) using an F6 recombinant inbred population. Of the 403 microsatellite markers screened, 82 were mapped on the seven linkage groups (LGs) that covered a total genetic distance of 799.9 cM, with an average marker interval of 10.7 cM. LG5 had the longest and LG7 the shortest genetic lengths, whereas LG1 had the maximum and LG7 the minimum number of markers. Segregation distortion of microsatellite loci was high (61%), with the majority of them (76%) skewed towards the female parent. Genomewide non-parametric single-marker analysis in combination with multiple quantitative trait loci (QTL)-models (MQM) mapping detected 26 definitive QTLs for bast fibre quality, yield and yield-related traits. These were unevenly distributed on six LGs, as colocalized clusters, at genomic sectors marked by 15 microsatellite loci. LG1 was the QTL-richest map sector, with the densest colocalized clusters of QTLs governing fibre yield, yield-related traits and tensile strength. Expectedly, favorable QTLs were derived from the desirable parents, except for nearly all of those of fibre fineness, which might be due to the creation of new gene combinations. Our results will be a good starting point for further genome analyses in jute.

Nondestructive characterization of Li+ ion-doped multifunctional poly(vinylidene fluoride)-g-poly(dimethyl amino ethyl methacrylate) by impedance spectroscopy

Poly(vinylidene fluoride) (PVDF)-graft-poly(dimethyl amino ethyl methacrylate) (PDMAEMA) (PD copolymer) is produced via atom transfer radical polymerization from PVDF solution in N-methyl-2-pyrrolidone. PD copolymer is doped with 1% and 5% (w/w) Li(+) ion to produce PDLi1 and PDLi5 samples, respectively. In PD copolymer, the crystalline structure of PVDF changes from α polymorph to a mixture of α and β polymorph, and it transforms completely to piezoelectric β polymorph on doping with 1% (w/w) Li(+) ion. The impedance behavior of PVDF changes on grafting, and that of the PD graft copolymer also changes with increasing Li(+) ion dopant concentration. In the Nyquist plots, PVDF exhibits a straight line character, and a curvature has appeared in the PD graft copolymer; on doping the latter with Li(+) ion (1% w/w), the curvature increases and a semicircle is completed on 5% Li(+) doping. Fitting the data from the Z-view program, the Ohmic resistance of PDLi1 is found to be 78 MΩ having capacitance with constant phase element (CPE) = 1.38 nF while for the PDLi5 sample the resistance decreases to16.1 MΩ with a small increase in CPE to 1.46 nF. The modulus plane plots for PDLi1 and PDLi5 samples also exhibit only one peak supporting the presence of only one equivalent resistance-capacitance circuit with constant phase element in both PDLi1 and PDLi5 samples. Both the impedance and modulus vs frequency plots of PDLi1 and PDLi5 samples exhibit a single Debye peak suggesting isotropic nature of the samples. For PVDF and PDMAEMA, ac-conductivity increases linearly with angular frequency, but in the case of PDLi1 and PDLi5 samples, it remains at first invariant in the frequency range 1-10(2) Hz, and above 10(2) Hz, an increase in conductivity with frequency occurs obeying the double power law. In the temperature variation of conductivity, PVDF exhibits its typical insulating nature, and in the PD graft copolymer, the conductivity decreases with increase of temperature (metallic-like behavior) due to gradual breaking of supramolecular interaction. The temperature variation of ac-conductivity of the Li(+)-doped PD graft copolymer suggests that both the ionic and supramolecular contributions of conductivity operate; the former increases and the latter decreases with rise in temperature showing a maximum. The temperature-dependent FTIR spectra of PDLi1 and PDLi5 samples support the gradual breaking of supramolecular interactions with increase of temperature.

Highly fluorescent graphene oxide-poly(vinyl alcohol) hybrid: an effective material for specific Au3+ ion sensors

We have developed a new highly fluorescent graphene oxide (GO)/poly(vinyl alcohol) (PVA) hybrid (GO-PVA) in an acidic medium (pH 4). Fourier transform infrared (FTIR) spectra indicate the formation of hydrogen bonds between the hydroxy group of PVA and the hydroxy groups of GO. The hybrid is highly fluorescent, because of passivation by hydrogen bonding, as evident from Raman spectra. The quantum yields of GO-PVA hybrids are higher than that of GO. The fluorescent microscopic images of the hybrids exhibit a fibrillar morphology, and all of them emit highly intense green light. Field-emission scanning electron microscopy (FESEM) micrographs also show a fibrillar morphology, which is produced due to the supramolecular organization of GO-PVA complex. The highly fluorescent GO-PVA1 hybrid has been used as a fascinating tool for selective sensing of Au(3+) ions in aqueous media with a detectable limit of ~275 ppb. The sensitivity of the Au(3+) ion (300 μM) in the presence of 600 μM concentrations of each ion (Cu(2+), Ag(+), Mg(2+), Ca(2+), Zn(2+), K(+), Pb(2+), Co(2+), Ni(2+), Pd(2+), Fe(2+), Fe(3+), and Cr(3+)), taken together, is unique, exhibiting a quenching efficiency of 76%. The quenching efficiency in the presence of a biologically analogous mixture (d-glucose, d-lysine, BSA, Na(+), K(+), Ca(2+), Mg(2+), Zn(2+)) (600 μM each) is 73%, which suggests that the GO-PVA1 hybrid is an efficient sensor of Au(3+) ions. The average lifetime of GO at pH 4 increases in the GO-PVA1 hybrid, indicating the formation of a more stable excited state but the increase in lifetime value after addition of Au(3+) salt solution to the hybrid solution indicates dynamic quenching. The selectivity of sensing of Au(3+) is attributed to its reduction potential being higher than that of other metal ions and XPS data of GO-PVA1 hybrid with 300 μM Au(3+) substantiate the reduction of Au(3+) to Au(0), because of the transfer of excitons from the hybrid facilitating the selective photoluminescence (PL) quenching.

Stability-indicating HPLC Method for Simultaneous Determination of Terbutaline Sulphate, Bromhexine Hydrochloride and Guaifenesin

The aim of the present study was the development and subsequent validation of a simple, precise and stability-indicating reversed phase HPLC method for the simultaneous determination of guaifenesin, terbutaline sulphate and bromhexine hydrochloride in the presence of their potential impurities in a single run. The photolytic as well as hydrolytic impurities were detected as 3,5-dihydroxybenzoic acid, 3,5-dihydroxybenzaldehyde, 1-(3,5-dihydroxyphenyl)-2-[(1,1-dimethylethyl) amino]-ethanone from terbutaline, 2-methoxyphenol and an unknown impurity identified as (2RS)-3-(2-hydroxyphenoxy)-propane-1,2-diol from guaifenesin. The chromatographic separation of all the three active components and their impurities was achieved on Wakosil II column, using phosphate buffer (pH 3.0) and acetonitrile as mobile phase which was delivered initially in the ratio of 80:20 (v/v) for 18 min, then changed to 60:40 (v/v) for next 12 min, and finally equilibrated back to 80:20 (v/v) for 10 min. Other HPLC parameters were: Flow rate at 1.0 ml/min, detection wavelengths 248 and 280 nm, injection volume 10 μl. The calibration graphs plotted with five concentrations of each component were linear with a regression coefficient R(2) >0.9999. The limit of detection and limit of quantitation were estimated for all the five impurities. The established method was then validated for linearity, precision, accuracy, and specificity and demonstrated to be applicable to the determination of the active ingredients in commercial and model cough syrup. No interference from the formulation excipients was observed. These results suggest that this LC method can be used for the determination of multiple active ingredients and their impurities in a cough and cold syrup.

Mooren''s ulcer following extracapsular cataract extraction

PURPOSE

Prior cataract surgery is a recognized risk factor for the development of Mooren''s ulcer, but the demographic and clinical features of a large cohort of such patients have not been described.

METHODS

The authors performed a retrospective review of demographic and clinical data from 14 eyes in 13 patients who developed Mooren's ulcer following extracapsular cataract extraction at Aravind Eye Hospital in Madurai, South India.

RESULTS

Eight (62%) of the 13 patients were men and 5 (39%) were women. The median age in our population was 65 years, with a range of 45 to 85 years. The median number of months from surgery to the onset of Mooren's ulcer was 19, with a range of 4 to 156 months. Of the 14 eyes with prior cataract surgery, the location of the ulcer was at or contiguous with the wound in 10 eyes (71%), which was 2.5 times more likely than other circumlimbal locations, and only one patient (8%) had bilateral disease.

CONCLUSIONS

Mooren''s ulcer may occur following extracapsular cataract extraction and when it does it is most likely to be unilateral and contiguous with the wound. These findings support the notion that exposure of normally concealed corneal antigens may contribute to the pathogenesis of Mooren''s ulcer in some patients.

Use of RAPD-PCR for genetic analysis of Nicobari fowl of Andamans

1. The present study was conducted to estimate genetic relatedness among Nicobari fowls (Brown, Black and White) and an exotic bird (White Leghorn) using random amplified polymorphic DNA (RAPD) polymorphism. 2. A total of 25 decamer primers were screened among all the breeds of which 24 primers amplified the genomic DNA, generating 2000 to 200 bp bands. Ten primers generated reproducible and distinct RAPD profiles and were used for further analysis. 3. A total of 94 bands were amplified and 30 polymorphic bands (32%) were produced. The number of polymorphic loci ranged from 1 to 5 with an average of 3.0. 4. Among the native breeds Brown Nicobari showed higher genetic similarity (0.85) than Black Nicobari (0.80) and White Nicobari fowl (0.82). 5. Brown Nicobari showed high genetic similarity with Black Nicobari (0.87 +/- 0.029); least similarity was between White Nicobari and White Leghorn (0.77 +/- 0.028). 6. The RAPD profile of all Nicobari fowls on amplification with the primers PBG5 and PBA12 showed specific bands of molecular size 1050 and 785 bp, respectively. 7. The native breeds showed the least genetic distance with each other while White Leghorn appeared to be most distant from the native breeds.

An unusual case of a retained metallic arrowhead in the orbit and sphenoidal sinus

A case of retained metallic arrowhead in orbit and sphenoidal sinus through an unusual route is reported. The eyeball was removed because of a possible risk of sympathetic ophthalmia.