1.
Detoxification Potential Of Yeast Sludhe Ahainst Ochratoxin In Broiler Chicks
by Huma Mujahid | Dr. Abu Saeed Hashmi | Dr. Aftab | Miss Asma Waris.
Material type: ; Format:
print
Publisher: 2011Dissertation note: Ochratoxin the fungal secondary metabolite is a potent natural contaminant of poultry feed. Mycotoxins present in poultry feeds from the raw material used in their production is the major cause of toxic feed. The intake of very low levels of Ochratoxin-A result in overt ochratoxicosis resulting in impairment of immune system and acquired resistance to infections causing health problems which lead to economic losses in the form of reduced productivity The research study was conducted to study the harmful effects of Ochratoxin on broiler chicks and the adsorptive potential of yeast sludge against Ochratoxin in broiler chicks .
Aspergillus ochraceus was grown on Sabraud's Dextrose Agar and ochratoxin was produced on fermented wheat grains .One fifty day old Chicks of broiler breed were purchased from Big birds hatchery and were raised on commercial broiler diet till 7 days.
Four diets A,B,C and D were formulated A diet serve as control, B diet contained OTA 500ppb, C diet contained OTA 500ppb and 1% Yeast sludge and D diet contained OTA 500ppb and 2% Yeast sludge. These four diets were assigned randomly to the chicks, such that there were three replicates on each ration and each replicate contained 10 chicks. Vaccination against N.D and IBD was performed according to the schedule. During feeding trial weight gain , feed consumed, FCR and mortality rate was determined.
Group B (500ppb OTA) showed a decrease in weight gain and feed consumption as compared to group A (control diet) , C (1% yeast sludge and 500ppb OTA) and D (2% yeast sludge and 500ppb ochratoxin). Group D showed more improvement in weight gain, feed consumption and FCR as compared to group C.
Blood serum and tissue samples were collected from the birds slaughtered at the end of experimental trial. Concentration of serum total protein, albumin and activity of alanine transaminase were determined. Blood Serum levels of total protein and albumin were lower in the group B (500ppb OTA) than group D having 2 % yeast sludge but the group C fed on 1% yeast sludge did not show much improvement in those parameters. Activity of ALT was found to be significantly higher (P<0.05) in group C as compared to all other groups. Whereas blood serum ALT activity of the birds fed on ration B was significantly high (P< 0.05) as compared to blood serum ALT of group A
The Level of Ochratoxin in Liver and Kidneys was also determined and it was found to be highest in Group B (500ppb OTA) and lowest in Group D (500ppb OTA + 2% yeast sludge).
Based upon the observations obtained in this study it can be concluded that ochratoxin-A is a nephrotoxic and hepatotoxic agent. But supplementation of 2% yeast sludge in the broiler diet can effectively detoxify the effects of ochratoxin as compared to supplementation of 1% yeast sludge in the chicks diet.
Availability: Items available for loan: UVAS Library [Call number: 1313,T] (1).
2.
Higher Production Of Algnate By A Mutant Of Azotobacter Vinelandii By Fermentation
by Saria Rahim | Ms. Shagufta Saeed | Dr. Muhammad | Ms. Huma Mujahid.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2012Dissertation note: Abstract Availability: Items available for loan: UVAS Library [Call number: 1521,T] (1).
3.
Bioconversion Of Whey To Beta-Galactosidase By Aspergillus Niger
by Muhammad Tayyab Younas | Ms. Huma Mujahid | Dr. Abu Saeed Hashmi | Ms. Sehrish.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2013Dissertation note: Beta-galactosidase (lactase) has catalytic property to hydrolyze lactose into glucose and galactose. It is extensively used for the synthesis of milk made products through fermentation. Food rich in lactose have variety of application in industrial and environmental processes.
In present study production, purification andcharacterization of ?-galactosidase synthesized by Aspergillus niger has been considered as a great challenge. Beta-glactosidase is an important enzyme involved in conversion of lactose into glucose and galactose and produced on industrial scale for its large applications in the field of health, and food. The production of beta-galactosidase was carried out from fungal culture of Aspergillus niger using whey as a substrate. Optimization of different physical parameters such as temperature, pH, addition of corn steep liquor and production, purification and characterization of beta galactosidase enzyme from Aspergillus niger were studied. Optimum concentration of whey (4mL) were found 13.42 IU/mL and activity of beta galactosidase was found maximum at 72 h of incubation period and further incubation period decline the activity.Optimum pH (13.50 IU/mL)and temperature (17.67 IU/mL) were found 5.5 and 40°C respectively. Addition of corn steep liquor was enhanced the activity of beta galactosidase. Maximum activity was found with 0.6% of corn steep liquor which was 19.4IU/mLas compare to the other nitrogen sources. Finally, addition of ammonium sulphate ?-galactosidase was purified. ?-galactosidase was characterized considering ortho-Nitrophenyl-?-galactoside (ONPG) and whey as a substrate The purified beta-galactosidase was confirmed by SDS PAGE analysis which has molecular weight of 74kDa. The study could also establish that whey could effectively be utilized for ?- galactosidase production thus alleviating water pollution problems caused due to its disposal into the water streams.
Availability: Items available for loan: UVAS Library [Call number: 1387,T] (1).
4.
Evaluation Of The Detoxification Potential Of Lactic Acid Bacteria From Curd And Whey Against Ochratoxin A In Broiler
by Afshan shabbir | Ms Huma Mujahid | Dr. Asif Nadeem | Dr. Muhammad Tayyab.
Material type: ; Format:
print
; Literary form:
drama
Publisher: 2013Dissertation note: Abstract Availability: Items available for loan: UVAS Library [Call number: 1657,T] (1).
5.
Bioconversion Of Agricultural Wastes To Polyhydroxybutyrate By Azotobacter Vinelandii
by Tehmina Aslam | Ms. Shagufta Saeed | Dr. Aftab | Ms. Huma Mujahid.
Material type: ; Format:
print
; Literary form:
drama
Publisher: 2014Dissertation note: Background
Polyhydroxybutyrate (PHB) is a biopolymer. It can be used as a biodegradable thermoplastic material for waste management strategies. It can be produced by various microorganisms. A bacterium, Azotobacter vinelandii accumulates PHB as intracellular granules inside their cells in response to physiological stress such as excess of carbon sources and limitation of nutrients e.g. nitrogen and phosphorus etc. During this research work PHB was produced from agricultural wastes like wheat bran and rice polishing through fermentation and by the optimization of different parameters like water substrate ratio, incubation time, volume of inoculum, pH and nitrogen concentration.
Methodology
A parent strain of Azotobacter vinelandii was maintained on Jerman agar plate. Fermentation media containing wheat bran and rice polishing as substrates was used to check the production of PHB for the selected bacteria. 0.5 ml of inoculum media was added into sterilized fermentation media and incubated for 24-72 hours. After that, culture media was centrifuged. Further extraction, determination and identification of PHB were carried out by using the pellet.
It was found that Azotobacter vinelandii gave maximum PHB yield (192mg/100mL) at 4% of wheat bran after 48 hours of incubation and at 5% of rice polishing after 36 hours (158mg/100mL). Wheat bran gave maximum PHB production (236mg/100mL) at 1.0mL volume of inoculum and rice polishing gave maximum yield (216mg/100mL) at 2.5mL. For wheat bran optimum pH was observed to be 7 to give higher PHB yield (256mg/100mL) and for rice polishing at pH 8.0 maximum PHB was observed (236mg/100mL). From wheat bran maximum quantity of PHB was produced at 0.2% of peptone (268mg/100mL) and at 0.3% of yeast extract (256mg/100mL) while in rice polishing based media higher PHB yield was studied at 0.25% of peptone (258mg/100mL) and at 0.2% of yeast extract (250mg/100mL). In this study Azotobacter vinelandii produced higher yield of PHB using wheat bran as compared to rice polishing.
Outcomes
So it is concluded that PHB produced in this work can be used in various industries like pharmaceutics, food industry and also in medical fields. It will also be helpful to reduce the pollution caused by other synthetic plastics.
Availability: Items available for loan: UVAS Library [Call number: 1818,T] (1).
6.
Effect Of Medicinal Plant Extracts On Genes Expression In Human Cervical Carcinoma
by Atika saeed | Dr. Muhammad Tayyab | DR | Ms. Huma mujahid.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2014Dissertation note: Abstract Availability: Items available for loan: UVAS Library [Call number: 1999,T] (1).
7.
A Studyof Pesticidues In Different Fruits Collected From Differentfruit Markets Of Lahore Punjab
by Muhammad shafi | Dr. Muhammad imran | Ms. Huma mujahid | Ms. Saeeda.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2014Dissertation note: Abstract Availability: Items available for loan: UVAS Library [Call number: 2037,T] (1).
8.
Biochemical And Histopathologica; Evaluation Of Detoxification Of Ochratoxin A By Lactic Acid Bacteria In Broiler Chickens
by Tanzila Wazir | Miss Huma Mujahid | Dr. Abu Saeed Hashmi | Miss. Maryam.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2014Dissertation note: Abstract Availability: Items available for loan: UVAS Library [Call number: 2102,T] (1).
9.
Delignification Of Rice Husk By Organic Solvent Treatment To Increase It’s In Vitro Digestibility
by Awais Alam (2012-VA-604) | Dr. AbuSaeed Hashmi | Miss Huma Mujahid | Dr. Asif Nadeem.
Material type: ; Literary form:
not fiction
Publisher: 2014Dissertation note: The major constituent of plant cell wall is lignocellulose. Plant biomass mostly consist of cellulose, hemicellulose and lignin alongside little measures of pectin, protein, extractives (dissolvable nonstructural materials, for example, sugars, nitrogenous material, chlorophyll, waxes) and ash. Lignocellulosic biomass is the most abundant organic material in nature. There is an expected yearly overall production of 10–50 billion dry tons representing about 50% of the worldwide biomass yield (Parveen et al. 2009).
Numerous physicochemical, structural and compositional variables decrease the digestibility of cellulose present in lignocellulosic material. So a treatment is required to increase the digestibility of lignocellulose biomass by exposing the cellulose present in plant fibers. Different techniques have been utilized for treatment, including chemical treatment, ammonia fiber explosion, biological treatment and steam explosion to modify the cellulosic structure to increase the availability of cellulose for digestion (Haoran et al. 2013). At that point, acids, bases and enzymes might be utilized to break down the cellulose into its respective sugars. Cellulolytic enzymesare broadly used to break down cellulose into its constituent sugars.
Among various agricultural wastes a broadly available waste is Rice husk (RH) which is rich in lignocellulosic material. Internationally, roughly 600 million tons of rice paddy is delivered every year. By and large 20% of the rice paddy is husk, giving a yearly aggregate generation of 120 million tons (Abbas et al. 2010). Pakistan is a rice producing country a great part of the husk produced from processing of rice is either blazed or dumped as waste. Rice husk yield in Pakistan is more than 1780 thousand tons every year (Asif et al. 2013).
Rice husk produced during rice refining, makes disposal issue because of less business interest. Additionally, handling and transportation of RH is hazardous because of its low density. Rice husk ash (RHA) is an incredible environmental risk bringing about harm to land and encompassing range here it is dumped. Thus, business utilization of rice husk and its ash is the option answer for disposal problem (Dilip et al. 2014).
RH are essentially made up of lignocellulose (60wt. %) and silica (11wt. %). The greater part of past investigations concentrated on the preparation of silica or other silicon based materials from RH, while the lignocellulose in RH was mostly glazed and then wasted. Thus, a methodology for comprehensive usage of RH has been produced to expand its digestibility by the breakdown of lignocellulosic mass. (Ajay et al. 2012)
Numerous techniques have been adopted for treating lignocellulosic feedstocks. However just a few of them appear to be encouraging. These treatment techniques include dilute acid treatment, steam blast (CO2 blast), pH controlled water treatment, ammonia fiber expension, ammonia recycle percolation (ARP) and lime treatment. Some survey articles have been appeared for microbial biomass treatment. But the present study gave presentations on organosolv treatment process. Despite the fact that organosolv treatment is more expensive at present than the leading treatment forms, it can give some significant side products. It appears that organosolv treatment is more practical for biorefinery of lignocellulosic biomass which considers the usage of every bit of biomass parts. An essential streamlining and usage of side products may lead the organosolv treatment to be a guaranteeing one for bio refining lignocellulosic feedstock in future. Organosolv treatment yields three different parts: dry lignin, a watery hemicellulose stream and a moderately pure cellulose division (Xuebing et al. 2009).
Availability: Items available for loan: UVAS Library [Call number: 2230-T] (1).
10.
DNA Based Characterization Of Protease Gene From Geobacillussp.Sbs-4s
by Anam Shabbir (2012-VA-608) | Dr. Muhammad Tayyab | Ms. Huma Mujahid | Prof. Dr. Tahir Yaqub.
Material type: ; Literary form:
not fiction
Publisher: 2014Dissertation note: Proteases are hydrolytic enzymes responsible for the hydrolysis of proteins(Qadar et al.2004).These enzymes contribute major role in textile and leather industry,accounting 60% of the world wide enzyme market(Nascimento et al.2004).These enzymes are also being used in food ,pharmaceutical ,detergent, brewage sweet industry and as digestive additives in human and animal feed (Wilson, 2012).
Proteases are produced by microbes,animal and plants but microbial proteases are preferred due to ease in production and cheaper cost (Ningthoujam et al.2010).Microbes produce a variety of proteases according to their requirement that are specific in their function (Neurath 1999).Microbes might be involved in the production of intra or extracellular proteases.Extracellular proteases help the organism to absorb and utilize hydrolytic products from proteinious substrates in order to get energy by catabolism or to synthesize the biomolecules through anabolism reactions(Ningthoujamet al.2010).
Proteases can be classified in different ways.On the basis of cutting preferences these can be divided in to two groups:endopeptidases and exopeptidases (Barret and Mcdonald 1985).Exopeptidases are involved in hydrolysis of the peptide bond near N or C terminal whereas endopeptidases are responsible for the hydrolysis of peptide bond, with the chain, distant from the peptide ends(Motyan et al .2013).On the basis of catalytic residues in active site the proteases can be divided into six groups including glutamate,serine, therionine cysteine,aspartate and metalloproteases(Li et al.2013).
Microorganisms occupy all possible environments including habitats that provides appropriate conditions for growth(Sharma et al.2009).Thermophiles have ability to grow at highertemperature whereas other microbes fail to survive.There has been increasing interest in thermophilic bacteria because of their thermostable enzyme(Obeidat et al.2012).Hyperthermophiles can survive in extremely hot environment. Hyperthermophiles occupy the most basal positions of the phylogenetic tree of life(Bouzas et al. 2006). About 70 species of hyperthermophilic bacteria and archea has been isolated from different terrestrial, marine and thermal areas in the world.Hyperthermophiles are very divergent in their phylogeny and physiological properties.Proteolytic enzymes from hyperthermophiles are catalytically active at high temperature and they can alsoretain their catalytic activity in the presence of detergent and other denaturing substances (Stetter et al.1993).
Geobacillusis widely distributed thermophiles isolated from geothermal areas (Chalopagorn et al.2014).On the basis of16SrRNA gene sequences, Geobacillus belongs to Bacillus genetic group 5. It is phenotypically and phylogeneticallyconsistent group of thermophilicbacilli (Rahman et al. 2007).Bacillus and Geobacillus species are the dominant workhorses in industrial biotechnology. These bacteria produce a variety of extracellular enzymes, such as amylases, xylanases, proteases, phytases, carbonic anhydrases, catalases, pectinases. Bacillus and Geobacillus species hasability to grow at acidic, alkaline, neutral pH and at elevated temperature has positioned them among the most important industrial enzyme producers(Satyanarayana et al. 2012).
Geobacillus are gram-positive, rod-shaped, aerobic,endospore-forming obligate thermophiles.The growth temperature for various Geobacillus species ranges from 37 to 75 °C and pH range of 6.0 to 8.5.The members of Geobacillusare homologus to each other and share homology 99% among them(Tayyab et al.2011). The genus Geobacillusthermophilicstrains, produce a variety of thermostable hydrolytic extracellular enzymes, such as proteases, amylases, and lipases used in various industrial applications (Wiegand et al. 2013)
GeobacillusSBS-4S was isolated from a hot spring located in Gilgit, Northern areas of Pakistan.Geobacillus SBS-4S strain is Gram positive, rod-shaped bacteria and occurs in chains. That could grow at a wide range of temperature (45 to 75˚C) and pH ranging 5.5 to 9.5.Geobacillus SBS-4S produced several extracellular enzymes including amylase, protease and lipase.The comparison of the strain SBS-4S with the already reported species of genus Geobacillus showed that SBS-4S is resistant to antibiotics such as streptomycine, spectinomycin and rifampicin(Tayyab et al.2011).
Availability: Items available for loan: UVAS Library [Call number: 2242-T] (1).
11.
Mutation Analysis Of Alpha-Synuclein Gene In Patients With Parkinson Disease
by Iffat Aleem (2009-VA-566) | Dr. Asif Nadeem | Prof. Dr. Tahir Yaqub | Ms. Huma Mujahid.
Material type: ; Literary form:
not fiction
Publisher: 2015Dissertation note: Parkinson disease is a complex, heterogeneous and chronic neurodegenerative disorder with a cumulative prevalence of greater than one per thousand, caused by neuronal loss, mainly affecting dopaminergic neurons of the substantia nigra. Parkinson disease is an idiopathic disorder of the extra pyramidal system characterized by tremors. Genetic factors contribute to its complex pathogenesis. A functional repeat polymorphism in the α-synuclein (SNCA) gene promoter conveys susceptibility for Parkinson disease. The α-synuclein (SNCA) has been implicated in rare autosomal dominant forms of Parkinson disease. The mutations in α-synuclein were associated with severe disease progression and a typical physical signs, indicative of neuro degeneration extending beyond the substantia nigra. Mutation in α-synuclein gene may have association with dopaminergic neuronal loss in Parkinson disease. Blood samples were collected from Parkinson disease patients. DNA was extracted by organic method. Primers were designed using Primer3 software. Amplification of gene was done by Polymerase Chain Reaction. PCR products were sequenced bi-directionally on ABI 3130XL Genetic analyzer. Sequence alignment was performed for polymorphism identification. The analysis of identified polymorphism has been done by CHROMAS software. Sequences were aligned by BLAST tool of NCBI. The results of analysis showed that no mutation found in exonic region of α-synuclein (SNCA) gene in Pakistani individuals selected for this study. Any change in exonic region of α-synuclein (SNCA) gene is a rare cause of sporadic and familial Parkinson disease in different populations. Availability: Items available for loan: UVAS Library [Call number: 2325-T] (1).
12.
Identification Of Genetic Variations In Toll Like Receptor 1(Tlr-1) Gene To Evaluate Its Potential For Enhanced Resistance To Bovine Tuberculosis
by Shehar Bano (2013-VA-09) | Dr. Maryam Javed | Prof. Dr. Tahir Yaqub | Miss Huma Mujahid.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2015Dissertation note: Bovine tuberculosis is a disease caused by the species included in the Mycobacterium tuberculosis complex. Toll-like receptors (TLRs) are a family of conserved innate immune recognition receptors that trigger adaptive immune responses. TLR1 play an important role in host defense against mycobacteria, especially by mediating the response to mycobacterial triacylated lipopeptides.
The objective of this study is the identification of single nucleotide polymorphisms within the coding region of TLR1 gene to evaluate its potential for enhanced the resistance to bovine tuberculosis in Nili-Ravi buffalo breed. Fifty blood samples of Nili-Ravi breed were collected from UVAS Pattoki Campus, Research Farm B and Buffalo Research Institute (BRI) Pattoki. Inorganic method was used for DNA extraction, for amplification of the coding region of TLR1 gene PCR (Polymerase Chain Reaction) was used using specially designed primers and the PCR products were sequenced through Sanger’s Chain Termination method. For the analysis and alignment of sequencing the results obtained after sequencing were analyzed and aligned using the CLUSTAL W and BLAST software. After all these analysis Ten SNPs were identified in the coding region of TLR1 mentioned in table.
The Ten SNPs identified in the coding region of TOLL LIKE RECEPTOR 1 were in this order P1 C>T, P2 T>C, P3 T>C, P4 T>C, P5 T>C, P6 C >T, P7 T>C, P8 C >T, P9 A>G and P10 A>G. The one SNP found in the current research is in compliance with the (Sun et al. 2012) research on TOLL LIKE RECEPTOR 1 hence Nine SNPs found in the current research are novel in Nili Ravi buffalo. The SNPs in the exonic region that is P1 C>T, P2 T>C, P3 T>C, P4 T>C, P5 T>C, P6 C >T, P7 T>C, P8 C >T, P9 A>G and P10 A>G were all transitions i.e. the conversion of purines to purines.
Population genetic analysis and allelic distribution at all loci was analyzed using POPGENE 32 software indicated that at [P3=0.243009> 0.05] followed the assumptions of the Hardy-Weinberg equilibrium indicating that the alleles were randomly distributed throughout the population, no migration had occurred, no bottlenecks happened and population remained large in numbers.This Non-significant and obeying HWE, so can be potential marker for genetic selection.At [P1= 0.040418< 0.05], [P2=0.033603< 0.05], [P4=0.000649< 0.05], [P5=0.000262< 0.05], [P7=0.015112< 0.05] and [P9=0.000111< 0.05] the probability value below 0.05 indicated that population at these polymorphic sites was not obeying Hardy-Weinberg equilibrium. This indicated that at these positions alleles were not equally distributed in population. It can be concluded from my research that the SNPs identified in the current research may also hold potential for marker-assisted breeding programs, with the aim of breeding more BTB-resistant animals and herds within both the national farms and the private sector.
Availability: Items available for loan: UVAS Library [Call number: 2335-T] (1).
13.
Polymorphism Study Of Calcium-Sensing Receptor Gene (Casr)In Calcium Nephrolithiasis Affected Families
by Hafza Ammara (2013-VA-865) | Dr. Muhammad YasirZahoor | Dr. Asif Nadeem | Ms. Huma Mujahid.
Material type: ; Literary form:
not fiction
Publisher: 2015Dissertation note: Nephrolithiasis is a multi-factorial kidney stone disease resulting from the combined influence of epidemiological, biochemical and genetic risk factors. Calcium-sensing receptorprotien is plasma membrane G protein-coupled receptors that regulate secretion of parathyroid hormoneand calcium re-absorption by kidney tubular cells. This protienis able to sense small changes in circulating calcium concentration and, once activated, it inhibits parathyroid hormone secretion and renal tubule calcium re-absorption. The CaSR gene protein islocated on chromosome 3q13 is one of the candidate gene explaining individual predispositions to calcium nephrolithiasis. CaSR gene is a predecessor for nephrolithiasis due to its role in calcium re-absorption. CaSRgene has seven exons and several mutations have been reported globally related to calcium nephrolithiasis.
Twenty families affected with calcium nephrolithiasis having at least two affected individuals have been enrolled for this study. Ten families have already been analyzed for exon 3 & 4 in the laboratory. DNA has been extracted through inorganic extraction method from the blood of newly enrolled families. Primers have been designed for exon 5, 6 and 7 through Primer3 software. These exons have been sequenced using the BigDye Terminator Cycle Sequencing Ready Reaction Kit (Perkin Elmer/ABI) and have been read in an automated sequencer, ABI Prism model 3730 (Perkin Elmer).
We also screend the coding exon of CLDN14 genewhich is a membrane protein that regulates paracellular passage of ions and small solutesat epithelial tight junction.The overexpression of claudin-14 in the thick ascending limb of loop of henleof the kidney generates a renal phenotype characteristic with hypomagnesemiaand hypercalciuria that leads to the development of calcium nephrolithiasis.
All of the sequences have been evaluated by using Clustal-W programs, Chromas and Bioedit software for mutational analysis.Sequence analysis of CaSR gene revealed one novel splice mutationC>G at position 63722 at exon 5 in one affected family.This variation is found in the intronic region of the gene.We found one missense mutation Q536R at exon six in three different affected families. And one synonymous single nucleotide polymorphism(SNP) C>G found at exon 7at rs2036400 in six different affected families.These SNPs showsa significant association of CaSRgene with nephrolithiasis. It will help to determine the risk factor and role of CaSR gene in inheritance of calcium nephrolithiasis. And it will also be used for genetic screening and prenatal diagnosis.
Availability: Items available for loan: UVAS Library [Call number: 2426-T] (1).
14.
Biochemical And Homology Analysis Of Jak2 Gene In Canines And Hominidae
by Marya Saadullah Khan (2014-VA-324) | Ms. Huma Mujahid | Dr. Abu Saeed Hashmi | Dr. Muhammad Yasir Zahoor.
Material type: ; Literary form:
not fiction
Publisher: 2016Dissertation note: Cancers are considered to be the most lethal of all diseases known out of which myeloproliferative neoplasms comprise of a very little percentage.The frequency of these disorders is known in human beings and a lot of work has been done on humans. But there is a lot of scope for research on this area in canines. As dogs were found to have strong homology with human beings, we compared canine cJAK2 exon 13 sequence with the humanhJAK2 exon 13 and found 96 % homology. Mutations in JAK2 gene are well known to cause three types of disorders i.e. polycythemia vera caused by a well-known point mutation in exon 14 causing substitution of valine for phenylalanine in JH2 domain of the protein.Essential thrombocythemia and idiopathic myelofibrosis may also be caused by this mutation but similar clinical conditions arise without the presence of this mutation. Studies have revealed that other point mutations such as deletion, addition or substitution are also responsible for these disorders.
JAK2 is an intracellular protein which performs phosphorylation of STAT molecules upon their activation. Although the whole protein in its good state is important for its function but the two domains JH1 and JH2 are vital. JH1 domain acts as a tyrosine kinase enzyme and its activity is controlled by JH2 domain also known as pseudo tyrosine kinase domain. Any mutation in these domains leads to protein conformation defect and thus prevents its performance. Besides V617F mutation, other mutations are being discovered in this part of gene. Researchers have found mutations in exon 12, 13 and 15 that have been found to be involved in development of myeloproliferative neoplasms in different cases of patients.
Blood picture do not reveal any direct clue except for increased erythrocytes alone or along with other cells like increased platelets. Therefore blood indices are not reliable parameter to indicate the type of mutation involved in these disorders. Also LDH and EPO levels are not correlated with the disorder. Although EPO test must be done to exclude the possibility of secondary PV and erythropoiesis.
Availability: Items available for loan: UVAS Library [Call number: 2544-T] (1).
