Shahid Nadeem

Characterization of Pasteurella multocida strains isolated from cattle and buffaloes in Karachi, Pakistan

Pasteurella multocida is a Gram-negative, non-motile coccobacillus. The organism is of special significance in the tropical countries including Pakistan where only in Punjab Province, it caused heavy economics losses as Rs.2.17 billion per year. We Isolated and identified the disease causing serotypes in Pakistan by using cultural, morphological and biochemical tests. Pathogenicity was confirmed by inoculation of the isolates in rabbits. Serotyping of the isolates was done and our isolates were found to be P. multocida , B: 2 serotype. Polymerase chain reaction (PCR) of 16s ribosomal deoxyribonucleic acid (rDNA) was done which amplified 1500 bp deoxyribonucleic acid (DNA) fragment. DNA sequencing and phylogenetic analysis of the gene revealed that our isolates are different from each other and they belong to two different groups. Whereas these isolates are closely related with P. multocida, sub species multocida, P. multocida and sub species septica.

Infection of hepatitis C virus genotypes in hepatocellular carcinoma patients from rural areas of Faisalabad region, Pakistan

The aim of this retrospective study was to investigate the infection of hepatitis C virus (HCV) genotypes in hepatocellular carcinoma (HCC) patients from rural areas of Faisalabad region. Among 179 HCC subjects, men and women were 51 and 49%, respectively. All samples positive for HCV RNA by qualitative PCR were genotyped, applying genotype-specific PCR. They were confirmed using HCV 5’ non-coding region sequence analytical data. Major risk factor for HCC development and progression was identified to be chronic HCV. It was found among 56.5 ± 2.1 years of age. All these HCC cases were HCV-related and no case was linked with other types of viruses. Using genotype specific primers, HCV genotype 3a (55.3%) was significantly (P<0.0001) higher, followed by 3b (15.8%), 1 (9.24%), 4 (8.05%) and 2 (7.15%). Other genotypes, namely 5a and 6a were only 1.19 and 1.05% among the HCC patients. About 1.05% remained un-typed because of minute viral load. HCV genotype 3a was strongly linked with HCC, followed by 3b. Moreover, HCC was linked with liver cirrhosis (81%). It is suggested that genotyping may be recommended before starting interferon therapy. Key words : Etiology, genotyping, hepatitis C virus, hepatocellular carcinoma, prevalence, α-fetoprotein.

Investigation of simple sequence repeats (SSR) marker- assisted genetic diversity among upland Bt- and non Bt-cotton varieties

Genetically modified with insect resistance gene (Cry1AC) and hybrid Bt-cotton genotypes were developed to redress cotton leaf curl virus epidemic. In this study, genetic diversity of 6 Bt- and 14 nonBt upland cotton genotypes was detected using simple sequence repeats (SSR) or micro-satellite markers. Out of 31 primer pairs, only 7 (22.6%) yielded polymorphic amplicons of 80 to 340 bp. The average loci per primer were 3.16 and 78.6% of them were informative. The unweighed pair-group method with arithmetic averages (UPGMA) dendrogram placed Bt- and non-Bt cotton varieties into four major groups. With the exception of 4 accessions (being similar), genetic dissimilarity coefficient among all other genotypes ranged from 0.50 to 0.98 suggesting a wide genetic heterogeneity among the selected collection. The lowest similarity was found between BH-160 and CIM-482, CIM-496 and MNH554, BH-160 and CIM-473, SARMAST and BH-160 (non-Bt cultivars), respectively as were some Btcultivars. In contrast to previous reports, these results show that some Bt- and non-Bt-cotton cultivars form a genetically diverse population. They could be used in future breeding programmes to develop new elite cotton cultivars.