Mutation Screen Of "Gamma-Aminobutyric Acid (Gaba)-A Receptor, Gamma 2" In Punjab Population
Material type: Book ; Format:
; Literary form:
Publisher: 2012 Dissertation note: Epilepsy is a formidable form of neural disorder that can impose its long lasting effect on person's life and development. To date, it lacks any effective therapy and is multistep disease strengthened by an overwhelming number of genetic and epigenetic mechanisms that streamline epileptic attacks. This particular study encompasses two major types of epilepsy, CAE and GTCS by targeting a GABRG2 gene. Mutation analysis of the coding exons (exon 3, 5 and 9) was performed by direct sequencing of GABRG2 in order to sought out complex biological entities in both types of epilepsies. GABRG2 is a molecule that has recently been characterized as the culprit for epileptic seizures onset. GABRG2 encodes GABA receptor that is fundamental inhibitory neurotransmitter in mammalian brain and is a ligand-gated chloride channels. This ligand-receptor coupling results in the inward shuttling of chloride ions through the channels and this hyperpolarizes the neurons, which induce the inhibitory effect of neurotransmitters. Direct sequencing of candidate gene "GABRG2" traced out a single polymorphic site in the exon 3 of the CAE as well as GTCS cases. However, this single nucleotide alteration is more commonly identified in childhood absence epilepsy patients as compared to the generalized cases. Silent mutation was identified at locus 27909 C>T of 46.66% of the total screened or analyzed cases.
Availability: Items available for loan: UVAS Library [ Call number: 1500,T] (1).
Polymorphisms Of Bovine Tumor Necrosis Factor Alpha Gene And Its Association With Mastitis In Sahiwal Cows
Material type: Book ; Literary form:
Publisher: 2015 Dissertation note: Mastitis is one of the shocking maladies of milch animals causing high production losses to livestock industry of Pakistan (Kenyanjui et al. 2011). It is an inflammatory condition of udder; represent a major problem in dairy cow management. It is one of the most common and frequent disease of dairy industry. Producers suffer a huge loss due to veterinary treatment costs and necessary culling of the infected animals. It negatively affects the milk production, quality of milk, and farm economics (Fourichon et al. 2005). Increasing the disease resistance among dairy cattle is therefore desirable because without controlling mastitis, the national goals of developing dairy farming on commercial and scientific lines and production of wholesome milk which conforms to the standards of WTO Accord would remain elusive.
Mastitis is inflammation of udder that caused by physiological and metabolical changes (Schalm and Noorlander 1957). There are two main types of mastitis; clinical mastitis (characterized by classical symptoms i.e., swelling of udder, redness, clumps and clots in milk etc) and sub-clinical mastitis (not show any symptoms, Milk appear normal, udder appear normal) (Schrick et al. 2001). Mastitis is ranked as a top disease of dairy herds (Rinaldi et al. 2010). This mammary gland infection caused by pathogenic micro organisms such as Staphylococcus aureus, Streptococcus uberis, and Esherichia coli in the mammary gland (Heringstad et al. 2000).
India, China and United States are the larger producer of milk and Pakistan is on forth number in milk yield. Pakistan almost produces 36.5 million tons of milk yeild per year (Cady et al. 1983).The Sahiwal breed is well known among for its superior dairy qualities (Barker et al. 1998). Both cross and pure breed Sahiwal cows have high milk production rate (Khan et al. 2013).
It is very difficult to comprehend this disease because numerous environmental and genetic factors are involved in the origin and development of mastitis (Bradley 2002; Carvajal et al. 2013). Susceptibility and resistance to mastitis is a complex trait influenced by genetic variation of animals. Among these variations, the polymorphisms in immunity genes are principal key factors in defensive mechanism of mammary gland (Ibeagha-Awemu et al. 2008).
The mammary gland tissue is protected by immune system by two defense system; innate and acquired immunity. Innate immunity response by the host is a quick response of bacterial defense system (Mesquita et al. 2012). Innate system is a rapid and effective mechanism that activated on recognition of antigen (Akira et al. 2006). Innate immune system is activated when specific pattern recognition receptors (PRR) that are present on the surfaces which are attach to the specific pathogen (Shuster et al. 1996). PRR are presnt on leucocytes in milk and on the epithelial cells lining of udder. It is reported that T- lymphocyte subset i.e., CD4+, CD8+ and ɤδT are present in infected bovine mammary glands. (Goldammer et al. 2004; Strandberg et al. 2005).
Innate defense (nonspecific) of the mammary gland is stimulated by the physical barrier such as teat end, natural killer (NK) cells, neutrophils, macrophages and certain other soluble factors. The teat cannals are considering the main line of defense. Microorganisms enter from teat canal in milk. The main roles of teat sphincter muscles are to remain orifice close so that bacteria cannot enter. This teat canal also lined with keratin, whose estrified and non estified fatty acid function as bacteriostatics that provide protection and play role to eliminate bacteria causing mastitis (Oviedo-Boyso et al. 2007).
If a pathogen is not eliminated by the physical barrier, the acquired immune system is triggered. In comparison, this system is much faster than other immune response. The memory response is significantly stronger, long durable and more efficient to kill the pathogen. The acquired immune system (memory response) have ability to differentiate self or nonself cells and produce antibodies only against antigens through membrane bound protein called major histocompatibility complex (MHC) molecules. Specific immune system activate only when antigens bind with an MHC that is present on the surface of certain cells, this process is referred as antigen presentation. Recognition of pathogenic factors for elimination is mediated by macrophages, several lymphoid, and immunoglobulins (Ig) or antibodies (Sordillo and Streicher 2002).
The most acute responding macrophages and T-cell cytokines are TNF-α, LTF, IL1, IL6, IL8, and IFN-ɤ present in intramammary infection in cows. These genes play important role in improvement of immunity to mastitis (Burton and Erskine 2003).
Tumor necrosis factor alpha is main pro-inflammatory adipokine that is part of systematic immune defense. The main function of TNF-α gene is responsible for proliferation, differentiation and activity of many immune system cells; B lymphocytes, NK (natural killer). It also induces the production and release of many other cytokines (Wojdak Maksymiec et al. 2013) and also enhances the chemotactic and phagocytic effects of immune response. TNF-α gene contains four exons and three introns that are present on chromosome BTA23q22 (Bannerman 2009; Moyes et al. 2009).
TNF-α is a member of a group of cytokines that stimulate the specific immune system. TNF consist of 212 amino acid arranged in stable homotrimers (Kriegler et al. 1988; Tang et al. 1996). The 17-kilodalton (kDa) TNF protomers are composed of two β-pleated sheets and β-strands, joined together antiparallel (Tang et al. 1996).
TNF-α is a component of natural protection systems of humans and animals. Milk gives nourishment and disease resistance to the new born. Various cellular and soluble immune components are important for protecting the mammary gland from infectious diseases like mastitis. Mastitis affects one third of all dairy cows and cost the dairy industry about 2 million dollars annually (National Mastitis Council (1996). Dairy cattle are especially susceptible to mastitis due to diminished mammary gland defense mechanisms (Sordillo and Streicher 2002).
TNF-α is not only produced by activation of macrophages, but also other cell types such as CD4+ lymphocytes, NK cells, neutrophils, mast cells, eosinophils, and neurons. Large amounts of TNF are released in response to lipopolysaccharide, other bacterial products, and Interleukin-1 (IL-1).TNF-α stimulates the proliferation, differentiation and activity of many immune system cells; B lymphocytes, NK (natural killer). TNF-α induces the release of many other cytokines (Wojdak-Maksymiec and Mikolajczyk 2012). TNF-α also enhance the chemotactic and phagocytic effects of immune response.
. The present study is designed to determine the genetic polymorphism in exon 4 of TNF-α gene of mastitic cows and its association resistance and susceptibility towards mastitis.
Availability: Items available for loan: UVAS Library [ Call number: 2224-T] (1).