Prevalence and molecular detection of contagious bovine pleuropneumonia in large ruminants in Punjab, Pakistan.

Contagious bovine pleuropneumonia (CBPP) is a highly contagious disease of cattle caused by Mycoplasma mycoides subsp. mycoides. It is characterized by anorexia, fever, dyspnea, polypnea, cough, and nasal discharges. Gross lesions in the lung such as marbling, sequestra, thickening of interlobular septa, and consolidation are evident. Serological tests including complement fixation test and competitive enzyme-linked immunosorbent assay and molecular tests such as polymerase chain reactions are used for diagnostic purposes. In this study, lung samples of suspected large ruminants (cattle n=560, buffalo n=293) were collected from abattoirs of three districts of Punjab namely Lahore, Kasur and Jhang. PCR was performed with specific primers, targeting the 16S ribosomal RNA gene to detect the positive cases. The results indicated that 49 samples (8.75%) of cattle were positive, with maximum prevalence was observed in Jhang with 16 positive samples (10.06%), but CBPP was not detected in any buffalo sample. High prevalence of disease was seen in cattle of more than seven years of age, in female cattle, and in cross-bred cattle. Age and gender were found significantly associated (P<0.05) with the prevalence of the disease. Gene sequencing of identified 5 isolates of Mycoplasma mycoides subsp. mycoides had more than 99% similarities with the strains isolated from China, Italy, Australia and Tanzania and were categorized into a monophyletic group but strain isolated from Portugal had more than 55% variable regions, hence clustered separately. This study confirms the presence of contagious bovine pleuropneumonia in the country which can be a threat to the livestock export market and warrants the implementation of control measures to mitigate the economic losses associated with the disease.

Prevalence and molecular detection of contagious bovine pleuropneumonia in large ruminants in Punjab, Pakistan

@#Contagious bovine pleuropneumonia (CBPP) is a highly contagious disease of cattle caused by Mycoplasma mycoides subsp. mycoides. It is characterized by anorexia, fever, dyspnea, polypnea, cough, and nasal discharges. Gross lesions in the lung such as marbling, sequestra, thickening of interlobular septa, and consolidation are evident. Serological tests including complement fixation test and competitive enzyme-linked immunosorbent assay and molecular tests such as polymerase chain reactions are used for diagnostic purposes. In this study, lung samples of suspected large ruminants (cattle n=560, buffalo n=293) were collected from abattoirs of three districts of Punjab namely Lahore, Kasur and Jhang. PCR was performed with specific primers, targeting the 16S ribosomal RNA gene to detect the positive cases. The results indicated that 49 samples (8.75%) of cattle were positive, with maximum prevalence was observed in Jhang with 16 positive samples (10.06%), but CBPP was not detected in any buffalo sample. High prevalence of disease was seen in cattle of more than seven years of age, in female cattle, and in cross-bred cattle. Age and gender were found significantly associated (P<0.05) with the prevalence of the disease. Gene sequencing of identified 5 isolates of Mycoplasma mycoides subsp. mycoides had more than 99% similarities with the strains isolated from China, Italy, Australia and Tanzania and were categorized into a monophyletic group but strain isolated from Portugal had more than 55% variable regions, hence clustered separately. This study confirms the presence of contagious bovine pleuropneumonia in the country which can be a threat to the livestock export market and warrants the implementation of control measures to mitigate the economic losses associated with the disease.

Ultraviolet-light-driven doping modulation in chemical vapor deposition grown graphene.

The tuning of charge carrier density of graphene is an essential factor to achieve the integration of high-efficiency electronic and optoelectronic devices. We demonstrate the reversible doping in graphene using deep ultraviolet (UV) irradiation and treatment with O2 and N2 gases. The Dirac point shift towards a positive gate voltage of chemical vapor deposition grown graphene field-effect transistors confirms the p-type doping, which is observed under UV irradiation and treatment with O2 gas, while it restores its pristine state after treatment with N2 gas under UV irradiation. The emergence of an additional peak in the X-ray photoelectron spectra during UV irradiation and treatment with O2 gas represents the oxidation of graphene, and the elimination of this peak during UV irradiation and treatment with N2 gas reveals the restoration of graphene in its pristine state. The shift in the G and 2D bands in Raman spectra towards higher and then lower wavenumber also suggests p-type doping and then reversible doping in graphene. The controlled doping and its reversibility in large area grown graphene offer a new vision for electronic applications.

FROM Qutn TO Bt COTTON: DEVELOPMENT, ADOPTION AND PROSPECTS. A REVIEW.

Cotton has unique history of domestication, diversification, and utilization. Globally it is an important cash crop that provides raw material for textile industry. The story of cotton started from human civilization and the climax arrived with the efforts of developing transgenic cotton for various traits. Though conventional breeding brought steady improvement in developing resistance against biotic stresses but recent success story of gene transferfrom Bacillus thuringiensis into cotton showed game changing effects on cotton cultivation. Amongst various families of insecticidal proteins Bt Cry-toxins received more attention because of specificity against receptors on the cell membranes of insect midgut epithelial cells. Rapid Bt cotton adoption by farmers due to its economic and environmental benefits has changed the landscape of cotton cultivation in many countries. But the variable expression of Bt transgene in the newly developed Bt cotton genotypes in tropical environment is questionable. Variability of toxin level in different plant parts at various life stage of plant is an outcome of genotypic interaction with environmental factors. Temporal gene expression of Cry1Ac is also blamed for the epigenetic background in which transgene has been inserted. The presence of genotypes with sub-lethal level of Bt toxin might create resistance in Lepidopteron insects, limiting the use of Bt cotton in future, with the opportunityfor other resistance development strategies to get more attention like gene stacking. Until the farmers get access to more recent technology, best option is to delay the development of resistance by applying Insect Resistance Management (IRM) strategies.

Photocurrent response of MoS2 field-effect transistor by deep ultraviolet light in atmospheric and N2 gas environments.

Molybdenum disulfide (MoS2), which is one of the representative transition metal dichalcogenides, can be made as an atomically thin layer while preserving its semiconducting characteristics. We fabricated single-, bi-, and multilayer MoS2 field-effect transistor (FET) by the mechanical exfoliation method and studied the effect of deep ultraviolet (DUV) light illumination. The thickness of the MoS2 layers was determined using an optical microscope and further confirmed by Raman spectroscopy and atomic force microscopy. The MoS2 FETs with different number of layers were assessed for DUV-sensitive performances in various environments. The photocurrent response to DUV light becomes larger with increasing numbers of MoS2 layers and is significantly enhanced in N2 gas environment compared with that in atmospheric environment.

Detection of bacterial blight resistance genes in basmati rice landraces.

Aromatic basmati rice is vulnerable to bacterial blight disease. Genes conferring resistance to bacterial blight have been identified in coarse rice; however, their incorporation into basmati varieties compromises the prized basmati aroma. We identified bacterial blight resistance genes Xa4, xa5, Xa7, and xa13 in 52 basmati landraces and five basmati cultivars using PCR markers. The Xa7 gene was found to be the most prevalent among the cultivars and landraces. The cultivars Basmati-385 and Basmati-2000 also contained the Xa4 gene; however, xa5 and xa13 were confined to landraces only. Ten landraces were found to have multiple resistance genes. Landraces Basmati-106, Basmati-189 and Basmati-208 contained Xa4 and Xa7 genes. Whereas, landraces Basmati-122, Basmati-427, Basmati-433 were observed to have xa5 and Xa7 genes. Landraces Basmati-48, Basmati-51A, Basmati-334, and Basmati-370A possessed Xa7 and xa13 genes. The use of landraces containing recessive genes xa5 and xa13 as donor parents in hybridization with cultivars Basmati-385 and Basmati-2000, which contain the genes Xa4 and Xa7, will expedite efforts to develop bacterial blight-resistant basmati rice cultivars through marker assisted selection, based on a pyramiding approach, without compromising aroma and grain quality.

Raman fingerprint of doping due to metal adsorbates on graphene.

The properties of single-layer graphene are strongly affected by metal adsorbates and clusters on graphene. Here, we study the effect of a thin layer of chromium (Cr) and titanium (Ti) metals on chemical vapor deposition (CVD)-grown graphene by using Raman spectroscopy and transport measurements. The Raman spectra and transport measurements show that both Cr and Ti metals affect the structure as well as the electronic properties of the CVD-grown graphene. The shift of peak frequencies, intensities and widths of the Raman bands are analyzed after the deposition of metal films of different thickness on CVD-grown graphene. The shifts in G and 2D peak positions indicate the doping effect of graphene by Cr and Ti metals. While p-type doping was observed for Cr-coated graphene, n-type doping was observed for Ti-coated graphene. The doping effect is also confirmed by measuring the gate voltage dependent resistivity of graphene. We have also found that annealing in Ar atmosphere induces a p-type doping effect on Cr- or Ti-coated CVD-grown graphene.

Genetic diversity analysis of Bt cotton genotypes in Pakistan using simple sequence repeat markers.

The popularity of genetically modified insect resistant (Bt) cotton has promoted large scale monocultures, which is thought to worsen the problem of crop genetic homogeneity. Information on genetic diversity among Bt cotton varieties is lacking. We evaluated genetic divergence among 19 Bt cotton genotypes using simple sequence repeat (SSR) markers. Thirty-seven of 104 surveyed primers were found informative. Fifty-two primers selected on the basis of reported intra-hirsutum polymorphism in a cotton marker database showed a high degree of polymorphism, 56% compared to 13% for randomly selected primers. A total of 177 loci were amplified, with an average of 1.57 loci per primer, generating 38 markers. The amplicons ranged in size from 98 to 256 bp. The genetic similarities among the 19 genotypes ranged from 0.902 to 0.982, with an average of 0.947, revealing a lack of diversity. Similarities among genotypes from public sector organizations were higher than genotypes developed by private companies. Hybrids were found to be more distant compared to commercial cultivars and advanced breeding lines. Cluster analysis grouped the 19 Bt cotton genotypes into three major clusters and two independent entries. Cultivars IR-3701, Ali Akbar-802 and advanced breeding line VH-259 grouped in subcluster B2, with very narrow genetic distances despite dissimilar parentage. We found a very high level of similarity among Pakistani-bred Bt cotton varieties, which means that genetically diverse recurrent parents should be included to enhance genetic diversity. The intra-hirsutum polymorphic SSRs were found to be highly informative for molecular genetic diversity studies in these cotton varieties.

Phylogenetic relationships among Saccharum clones in Pakistan revealed by RAPD markers.

Forty sugarcane genotypes (clones), including elite lines, commercial cultivars of Saccharum officinarum and S. barberi clones, were fingerprinted with 30 RAPD markers, using a PCR-based marker assay. The genetic distance for RAPD data was determined according to Nei, and relationships between accessions were graphed in a dendrogram. Genetic distance values ranging from 16.2 to 86.3% were observed among the 40 sugarcane accessions. The lowest genetic distance was found between genotypes US-406 and US-186. These two genotypes differed from each other in only 25 bands with 15 different primers. Genotypes Col-54 and CP-72-2086 were the second most similar group, with a genetic distance of 19.46%. The most dissimilar of all the accessions were CP-77-400 and US-133, with a genetic distance of 86.3%. RAPD fingerprints help sugarcane breeders clarify the genetic pedigree of commercial sugarcane varieties and can be used to evaluate the efficiency of conventional breeding methods.

Genetic studies of "noble cane" for identification and exploitation of genetic markers.

Forty genotypes (clones) of sugarcane, including elite lines, commercial cultivars of Saccharum officinarum and clones of S. barberi were fingerprinted with 50 SSR markers using a PCR-based marker assay. Nei's genetic distances for SSR data were determined and relationships between accessions were portrayed graphically in the form of a dendrogram. Genetic distance values ranging from 0.60 to 1.11 were observed among the 40 sugarcane accessions. The shortest genetic distance of 0.60 was seen between genotypes US-804 and US-130. These two genotypes differed from each other only in 10 bands, with 20 primers. The most dissimilar of the accessions were CP-77-400 and US-133, with a genetic distance of 1.11. SSR fingerprints can help sugarcane breeders to clarify the genetic pedigree of commercial sugarcane varieties and evaluate the efficiency of breeding methods.

DNA profiling of sugarcane genotypes using randomly amplified polymorphic DNA.

DNA profiles of 40 sugarcane genotypes were constructed with 30 RAPD markers. Sugarcane genotypes of both Saccharum officinarum and S. barberi were included in this study. Multiple alleles were detected from each RAPD; there was a high level of polymorphism. On average, 7.93 alleles were produced per primer, giving a total of 238 alleles. The genetic distances between these genotypes were assessed with the POPGENE DNA sequence analysis software. A dendrogram was constructed from these data; cultivated species of sugarcane formed clusters with S. barberi genotypes. The 40 genotypes were clustered into two main groups; genetic distances ranged from 20.29 to 64.66%. These RAPD fingerprints will help sugarcane breeders to evaluate the efficiency of current conventional breeding methods and will help characterize the genetic pedigree of commercial sugarcane varieties. These data will also be valuable for conservation and utilization of the genetic resources in germplasm collections.

A discordance between cytochrome P450 2D6 genotype and phenotype in patients undergoing methadone maintenance treatment.

AIMS: To assess CYP2D6 activity and genotype in a group of patients undergoing methadone maintenance treatment (MMT). METHODS: Blood samples from 34 MMT patients were genotyped by a polymerase chain reaction-based method, and results were compared with CYP2D6 phenotype (n = 28), as measured by the molar metabolic ratio (MR) of dextromethorphan (DEX)/dextrorphan (DOR) in plasma. RESULTS: Whereas 9% of patients (3/34) were poor metabolizers (PM) by genotype, 57% (16/28) were PM by phenotype (P < 0.005). Eight patients, who were genotypically extensive metabolizers (EM), were assigned as PM by their phenotype. The number of CYP2D6*4 alleles and sex were significant determinants of CYP2D6 activity in MMT patients, whereas other covariates (methadone dose, age, weight) did not contribute to variation in CYP2D6 activity. CONCLUSIONS: There was a discordance between genotype and in vivo CYP2D6 activity in MMT patients. This finding is consistent with inhibition of CYP2D6 activity by methadone and may have implications for the safety and efficacy of other CYP2D6 substrates taken by MMT patients.

Simultaneous determination of nitrite and nitrate by normal phase ion-pair liquid chromatography.

Normal phase ion-pair high performance liquid chromatography has been used for simultaneous separation of nitrite and nitrate using tetraethylammonium (TEA)(+) as ion-pairing reagent. The concentration effect of (TEA)(+), buffer salt and pH of the eluent on separation is investigated. The UV detector response at various wavelengths has been optimized. The performance of the proposed method is compared with ion chromatography for quantification of the anions in potable water, wastewater and in food samples, such as spinach and lettuce.

New steroidal alkaloids from Sarcococca saligna.

Five new pregnane-type steroidal alkaloids (1-5) have been isolated from Sarcococca saligna. A combination of UV, IR, MS, and 1D and 2D NMR spectroscopic studies established their structures as salignarine A [(20S)-2beta-hydroxy-4beta-acetoxy-5alpha, 6alpha-epoxy-20-(dimethylamino)-3beta-(tigloylamino)pregnane ] (1), salignarine B [(20S)-2beta-hydroxy-20-(dimethylamino)-3beta-(tigloylamino) -pregn-5- ene] (2), salignarine C [(20S)-2beta-hydroxy-20-(dimethylamino)-3beta-(senecioylamino++ +)-pregn- 5-ene] (3), salignarine D [(20S)-20-(dimethylamino)-3beta-(senecioylamino)-5alpha-preg n-16-ene] (4), and salignarine E [(20S)-20-(dimethylamino)-3beta-(tigloylamino)-pregn-4-ene] (5), respectively.