Kalpana Reddy - Academia.edu (original) (raw)
Papers by Kalpana Reddy
Journal of Investigative Dermatology, 2008
The Shb adapter protein is an Src homology 2-domain containing signaling intermediate operating d... more The Shb adapter protein is an Src homology 2-domain containing signaling intermediate operating downstream of several tyrosine kinase receptors, including vascular endothelial growth factor receptor-2. Shb is multifunctional and apoptosis is one response that Shb regulates. Inhibition of angiogenesis can be used in cancer therapy, and one way to achieve this is by inducing endothelial cell apoptosis. The angiosarcoma cell line SVR is of endothelial origin and can be used as a tool for studying in vivo inhibition of angiogenesis, and we thus employed an Shb-knockdown strategy using an inducible lentiviral system to reduce Shb levels in SVR cells and to study their responses. Shb knockdown increases the susceptibility of SVR cells to the apoptotic agents, cisplatin and staurosporine. Simultaneously, Shb knockdown causes reduced focal adhesion kinase (FAK) activation, monitored as phosphorylation of the regulatory residues tyrosines 576/577. No detectable effects on Akt or extracellular signal-regulated kinase activity were noted. The altered FAK activity coincided with an elongated cell phenotype that was particularly noticeable in the presence of staurosporine. In order to relate the effects of Shb knockdown to in vivo tumorigenicity, cells were exposed to the angiogenesis inhibitor honokiol, and again the cells with reduced Shb content exhibited increased apoptosis. Tumor growth in vivo was strongly reduced in the Shb-knockdown cells upon honokiol treatment. It is concluded that Shb regulates apoptosis and cell shape in tumor endothelial cells via FAK, and that Shb is a potential target for inhibition of angiogenesis.
Textbook of Hepatology, 2007
Journal of Cardiothoracic and Vascular Anesthesia, 2006
The Thromboelastogram (TEG; Haemoscope Corporation, Niles, IL) and the ROTEM thromboelastometry a... more The Thromboelastogram (TEG; Haemoscope Corporation, Niles, IL) and the ROTEM thromboelastometry analyzer (Pentapharm GmbH, Munich, Germany) are coagulation monitors that measure the viscoelastic changes accompanying whole-blood coagulation generation and lysis. It is not clear whether TEG and ROTEM transfusion algorithms suggest similar blood component intervention. This study aims to report the extent to which administration of platelets, fresh frozen plasma, and cryoprecipitate would be indicated using protocol-dictated interventions by the Rotem, TEG, and conventional coagulation screens during orthotopic liver transplantation (OLT). Prospective observational study. University hospital. Twenty patients undergoing orthotopic liver transplantation. Coagulation was managed with native TEG protocols. Additional samples for kaolin TEG, kaolin heparinase TEG, Rotem in-TEM, Rotem hep-TEM, Rotem fib-TEM, full blood count, prothrombin time, and Clauss fibrinogen assays were taken at 5 fixed operative stages. Results were reviewed and protocol-indicated interventions recorded. There was moderate agreement between Clauss fibrinogen and Rotem fib-TEM assays about fulfilling fibrinogen transfusion criteria (kappa = 0.42, p < or = 0.05). Agreement between TEG and Rotem to transfuse platelets was fair (Rotem in-TEM/native heparinase TEG, kappa = 0.33, Rotem in-TEM/kaolin heparinase TEG, kappa = 0.28). There was moderate agreement between Rotem in-TEM and prothrombin time (kappa = 0.42), and poor agreement between other tests about the point to administer fresh frozen plasma. Transfusion practice is likely to differ according to the method of coagulation monitoring used. A prospective case-matched study using the viscoelastic tests used in this study would be beneficial in determining the optimal therapy. Rotem fib-TEM monitoring may improve hemostasis management.
Journal of Crop Science and Biotechnology, 2011
Agrobacterium tumefaciens mediated in planta transformation protocol was developed for castor, Ri... more Agrobacterium tumefaciens mediated in planta transformation protocol was developed for castor, Ricinus communis. Two-day-old seedlings were infected with Agrobacterium strain EHA105/pBinBt8 harboring cry1AcF and established in the greenhouse. Screening the T1 generation seedlings on 300 mg L -1 kanamycin identified the putative transformants. Molecular and expression analysis confirmed the transgenic nature and identified high-expressing plants. Western blot analysis confirmed the co-integration of the nptII gene in the selected transgenic plants. Bioassay against Spodoptera litura corroborated with high expression and identified five promising effective lines. Analysis of the T2 generation plants proved the stability of the transgene indicating the feasibility of the method.
Scientia Horticulturae, 2009
Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate tr... more Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate transgenic plants in bell pepper. An alternate transformation method that avoids/minimizes tissue culture would be beneficial for the improvement of bell pepper due to its recalcitrant nature. In this report, transgenic bell pepper plants have been developed by a tissue-culture-independent A. tumefaciens-mediated in planta transformation procedure. In the present study, two open pollinated varieties viz., Arka Gaurav and Arka Mohini were used for transformation. Agrobacterium strain EHA105 harboring the binary vector pCAMBIA1301 that carries the genes for b-glucuronidase (uid A) and hygromycin phosphotransferase II (hpt II) was used for transformation. GUS histochemical analysis of T 0 and T 1 plants at various stages of growth followed by molecular analysis using PCR, Southern analysis and RT-PCR allowed selection of transgenics. The method resulted in 17.8% and 11.4% of the T 0 plants in Arka Gaurav and Arka Mohini being selected as chimeric and 35.0% and 29.7%, respectively, were identified as stable transformants in the T 1 generation based on PCR analysis. ß
Scientia Horticulturae, 2011
The recent progress on bell pepper transformation through in planta approach is incredibly simple... more The recent progress on bell pepper transformation through in planta approach is incredibly simple with high transformation efficiencies in indigenous varieties. This method produces chimeric primary transformants (T0) hence, a large number of T0 plants and an efficient high throughput screening strategy is necessary to be developed. In the present investigation, we have standardized a rapid and highly efficient method
Plant Molecular Biology Reporter, 2012
An improved protocol of using simple in planta transformation methods (Injection method and Cut m... more An improved protocol of using simple in planta transformation methods (Injection method and Cut method) were developed for Gossypium hirsutum. The frequency of transformation was 1.16 % for injection method and 0.83 % for cut method. The effect of different factors like age of explants, pH of co-cultivation medium, effect of kanamycin and co-cultivation time period of Agrobacterium tumefaciens on the efficiency of regeneration and transformation was studied. The combined result of this study shows that three days old seedlings inoculated with Agrobacterium and co-cultivated for three days in half strength MS medium at pH 5.8 had highest frequency of transformation.
Scientia Horticulturae, 2009
Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate tr... more Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate transgenic plants in bell pepper. An alternate transformation method that avoids/minimizes tissue culture would be beneficial for the improvement of bell pepper due to its recalcitrant nature. In this report, transgenic bell pepper plants have been developed by a tissue-culture-independent A. tumefaciens-mediated in planta transformation procedure. In the present study, two open pollinated varieties viz., Arka Gaurav and Arka Mohini were used for transformation. Agrobacterium strain EHA105 harboring the binary vector pCAMBIA1301 that carries the genes for β-glucuronidase (uid A) and hygromycin phosphotransferase II (hpt II) was used for transformation. GUS histochemical analysis of T0 and T1 plants at various stages of growth followed by molecular analysis using PCR, Southern analysis and RT-PCR allowed selection of transgenics. The method resulted in 17.8% and 11.4% of the T0 plants in Arka Gaurav and Arka Mohini being selected as chimeric and 35.0% and 29.7%, respectively, were identified as stable transformants in the T1 generation based on PCR analysis.
Scientia Horticulturae, 2011
The recent progress on bell pepper transformation through in planta approach is incredibly simple... more The recent progress on bell pepper transformation through in planta approach is incredibly simple with high transformation efficiencies in indigenous varieties. This method produces chimeric primary transformants (T0) hence, a large number of T0 plants and an efficient high throughput screening strategy is necessary to be developed. In the present investigation, we have standardized a rapid and highly efficient method of screening putative bell pepper transformants. Bell pepper transformants harbouring gfp genes was developed using in planta approach and 1050 etiolated T1 seedlings were screened using fluorescent microscope to select GFP positive plants. The molecular analysis such as, gene specific PCRs, semiquantitative RT-PCR and Southern blots analysis corroborated the transgene integration in selected T1 transformants. Based on progressive selection strategy, the transformation efficiency was 27.4% in gfp screened plants. The fluorescence based screening is viable, rapid, requires minimal labour, expense, and expertise with less percent of non-transformant escapes; further, this method can be extended from bell pepper to other crops to identify putative transformants developed through in planta approach.► T0 plants being chimeric this method needs large number of primary transformants. ► So far, no viable method of screening putative pepper transformants are available. ► 1050 etiolated seedlings screened based on gfp fluorescence using microscope. ► PCR, RT-PCR, Southern analysis confirmed the transgene integration in T1gfp plants. ► Overall transformation efficiency was 27.4% based on progressive selection strategy.
Archives Of Phytopathology And Plant Protection, 2009
Abstract A field study was conducted to investigate powdery mildew disease incidence and fruit yi... more Abstract A field study was conducted to investigate powdery mildew disease incidence and fruit yield of locally available bell pepper genotypes by Kharif 2004 and Rabi 2005. The study includes a single chemical molecule in managing the powdery mildew disease ...
Journal of Investigative Dermatology, 2008
The Shb adapter protein is an Src homology 2-domain containing signaling intermediate operating d... more The Shb adapter protein is an Src homology 2-domain containing signaling intermediate operating downstream of several tyrosine kinase receptors, including vascular endothelial growth factor receptor-2. Shb is multifunctional and apoptosis is one response that Shb regulates. Inhibition of angiogenesis can be used in cancer therapy, and one way to achieve this is by inducing endothelial cell apoptosis. The angiosarcoma cell line SVR is of endothelial origin and can be used as a tool for studying in vivo inhibition of angiogenesis, and we thus employed an Shb-knockdown strategy using an inducible lentiviral system to reduce Shb levels in SVR cells and to study their responses. Shb knockdown increases the susceptibility of SVR cells to the apoptotic agents, cisplatin and staurosporine. Simultaneously, Shb knockdown causes reduced focal adhesion kinase (FAK) activation, monitored as phosphorylation of the regulatory residues tyrosines 576/577. No detectable effects on Akt or extracellular signal-regulated kinase activity were noted. The altered FAK activity coincided with an elongated cell phenotype that was particularly noticeable in the presence of staurosporine. In order to relate the effects of Shb knockdown to in vivo tumorigenicity, cells were exposed to the angiogenesis inhibitor honokiol, and again the cells with reduced Shb content exhibited increased apoptosis. Tumor growth in vivo was strongly reduced in the Shb-knockdown cells upon honokiol treatment. It is concluded that Shb regulates apoptosis and cell shape in tumor endothelial cells via FAK, and that Shb is a potential target for inhibition of angiogenesis.
Textbook of Hepatology, 2007
Journal of Cardiothoracic and Vascular Anesthesia, 2006
The Thromboelastogram (TEG; Haemoscope Corporation, Niles, IL) and the ROTEM thromboelastometry a... more The Thromboelastogram (TEG; Haemoscope Corporation, Niles, IL) and the ROTEM thromboelastometry analyzer (Pentapharm GmbH, Munich, Germany) are coagulation monitors that measure the viscoelastic changes accompanying whole-blood coagulation generation and lysis. It is not clear whether TEG and ROTEM transfusion algorithms suggest similar blood component intervention. This study aims to report the extent to which administration of platelets, fresh frozen plasma, and cryoprecipitate would be indicated using protocol-dictated interventions by the Rotem, TEG, and conventional coagulation screens during orthotopic liver transplantation (OLT). Prospective observational study. University hospital. Twenty patients undergoing orthotopic liver transplantation. Coagulation was managed with native TEG protocols. Additional samples for kaolin TEG, kaolin heparinase TEG, Rotem in-TEM, Rotem hep-TEM, Rotem fib-TEM, full blood count, prothrombin time, and Clauss fibrinogen assays were taken at 5 fixed operative stages. Results were reviewed and protocol-indicated interventions recorded. There was moderate agreement between Clauss fibrinogen and Rotem fib-TEM assays about fulfilling fibrinogen transfusion criteria (kappa = 0.42, p < or = 0.05). Agreement between TEG and Rotem to transfuse platelets was fair (Rotem in-TEM/native heparinase TEG, kappa = 0.33, Rotem in-TEM/kaolin heparinase TEG, kappa = 0.28). There was moderate agreement between Rotem in-TEM and prothrombin time (kappa = 0.42), and poor agreement between other tests about the point to administer fresh frozen plasma. Transfusion practice is likely to differ according to the method of coagulation monitoring used. A prospective case-matched study using the viscoelastic tests used in this study would be beneficial in determining the optimal therapy. Rotem fib-TEM monitoring may improve hemostasis management.
Journal of Crop Science and Biotechnology, 2011
Agrobacterium tumefaciens mediated in planta transformation protocol was developed for castor, Ri... more Agrobacterium tumefaciens mediated in planta transformation protocol was developed for castor, Ricinus communis. Two-day-old seedlings were infected with Agrobacterium strain EHA105/pBinBt8 harboring cry1AcF and established in the greenhouse. Screening the T1 generation seedlings on 300 mg L -1 kanamycin identified the putative transformants. Molecular and expression analysis confirmed the transgenic nature and identified high-expressing plants. Western blot analysis confirmed the co-integration of the nptII gene in the selected transgenic plants. Bioassay against Spodoptera litura corroborated with high expression and identified five promising effective lines. Analysis of the T2 generation plants proved the stability of the transgene indicating the feasibility of the method.
Scientia Horticulturae, 2009
Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate tr... more Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate transgenic plants in bell pepper. An alternate transformation method that avoids/minimizes tissue culture would be beneficial for the improvement of bell pepper due to its recalcitrant nature. In this report, transgenic bell pepper plants have been developed by a tissue-culture-independent A. tumefaciens-mediated in planta transformation procedure. In the present study, two open pollinated varieties viz., Arka Gaurav and Arka Mohini were used for transformation. Agrobacterium strain EHA105 harboring the binary vector pCAMBIA1301 that carries the genes for b-glucuronidase (uid A) and hygromycin phosphotransferase II (hpt II) was used for transformation. GUS histochemical analysis of T 0 and T 1 plants at various stages of growth followed by molecular analysis using PCR, Southern analysis and RT-PCR allowed selection of transgenics. The method resulted in 17.8% and 11.4% of the T 0 plants in Arka Gaurav and Arka Mohini being selected as chimeric and 35.0% and 29.7%, respectively, were identified as stable transformants in the T 1 generation based on PCR analysis. ß
Scientia Horticulturae, 2011
The recent progress on bell pepper transformation through in planta approach is incredibly simple... more The recent progress on bell pepper transformation through in planta approach is incredibly simple with high transformation efficiencies in indigenous varieties. This method produces chimeric primary transformants (T0) hence, a large number of T0 plants and an efficient high throughput screening strategy is necessary to be developed. In the present investigation, we have standardized a rapid and highly efficient method
Plant Molecular Biology Reporter, 2012
An improved protocol of using simple in planta transformation methods (Injection method and Cut m... more An improved protocol of using simple in planta transformation methods (Injection method and Cut method) were developed for Gossypium hirsutum. The frequency of transformation was 1.16 % for injection method and 0.83 % for cut method. The effect of different factors like age of explants, pH of co-cultivation medium, effect of kanamycin and co-cultivation time period of Agrobacterium tumefaciens on the efficiency of regeneration and transformation was studied. The combined result of this study shows that three days old seedlings inoculated with Agrobacterium and co-cultivated for three days in half strength MS medium at pH 5.8 had highest frequency of transformation.
Scientia Horticulturae, 2009
Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate tr... more Agrobacterium tumefaciens-mediated transformation has been one of the methods used to generate transgenic plants in bell pepper. An alternate transformation method that avoids/minimizes tissue culture would be beneficial for the improvement of bell pepper due to its recalcitrant nature. In this report, transgenic bell pepper plants have been developed by a tissue-culture-independent A. tumefaciens-mediated in planta transformation procedure. In the present study, two open pollinated varieties viz., Arka Gaurav and Arka Mohini were used for transformation. Agrobacterium strain EHA105 harboring the binary vector pCAMBIA1301 that carries the genes for β-glucuronidase (uid A) and hygromycin phosphotransferase II (hpt II) was used for transformation. GUS histochemical analysis of T0 and T1 plants at various stages of growth followed by molecular analysis using PCR, Southern analysis and RT-PCR allowed selection of transgenics. The method resulted in 17.8% and 11.4% of the T0 plants in Arka Gaurav and Arka Mohini being selected as chimeric and 35.0% and 29.7%, respectively, were identified as stable transformants in the T1 generation based on PCR analysis.
Scientia Horticulturae, 2011
The recent progress on bell pepper transformation through in planta approach is incredibly simple... more The recent progress on bell pepper transformation through in planta approach is incredibly simple with high transformation efficiencies in indigenous varieties. This method produces chimeric primary transformants (T0) hence, a large number of T0 plants and an efficient high throughput screening strategy is necessary to be developed. In the present investigation, we have standardized a rapid and highly efficient method of screening putative bell pepper transformants. Bell pepper transformants harbouring gfp genes was developed using in planta approach and 1050 etiolated T1 seedlings were screened using fluorescent microscope to select GFP positive plants. The molecular analysis such as, gene specific PCRs, semiquantitative RT-PCR and Southern blots analysis corroborated the transgene integration in selected T1 transformants. Based on progressive selection strategy, the transformation efficiency was 27.4% in gfp screened plants. The fluorescence based screening is viable, rapid, requires minimal labour, expense, and expertise with less percent of non-transformant escapes; further, this method can be extended from bell pepper to other crops to identify putative transformants developed through in planta approach.► T0 plants being chimeric this method needs large number of primary transformants. ► So far, no viable method of screening putative pepper transformants are available. ► 1050 etiolated seedlings screened based on gfp fluorescence using microscope. ► PCR, RT-PCR, Southern analysis confirmed the transgene integration in T1gfp plants. ► Overall transformation efficiency was 27.4% based on progressive selection strategy.
Archives Of Phytopathology And Plant Protection, 2009
Abstract A field study was conducted to investigate powdery mildew disease incidence and fruit yi... more Abstract A field study was conducted to investigate powdery mildew disease incidence and fruit yield of locally available bell pepper genotypes by Kharif 2004 and Rabi 2005. The study includes a single chemical molecule in managing the powdery mildew disease ...