shreya sharma - Academia.edu (original) (raw)

Papers by shreya sharma

Research paper thumbnail of Magnetic bead purification of enveloped alphavirus and flavivirus

MethodsX, 2021

Virus production is an essential part of virology. The quality of virus preparation, in terms of ... more Virus production is an essential part of virology. The quality of virus preparation, in terms of purification and yield, can affect the outcome of experiments. Purified virus is critical for assays, as contamination from cell culture supernatants may affect results. Purified virus is also needed for vaccine preparations. The traditional process of gradient purification of virus is time consuming, with multiple steps spanning over days, and produces significant amounts of biohazard waste. Developing a more efficient alternative that provides a purified virus product is highly desirable. In this study, we performed magnetic bead purification of Zika virus (ZIKV) and Mayaro virus (MAYV) with the Mag4C LV kit from OZ Biosciences. Currently, this kit is only indicated for use with lentiviruses and retroviruses. We found that we were able to successfully concentrate and purify both ZIKV and MAYV using the kit. Therefore, we concluded that the Mag4C LV kit provides a quick and simple alternative to traditional virus purification methods.•Our protocol is customized by using an alphavirus (MAYV) and flavivirus (ZIKV). This method has not been previously used for these viruses.

Research paper thumbnail of Softwares in Orthodontics- a Review

INTERNATIONAL JOURNAL OF SCIENTIFIC RESEARCH, 2021

There has been a huge advancement in the orthodontic technology that enables an orthodontist to p... more There has been a huge advancement in the orthodontic technology that enables an orthodontist to plan the treatment precisely and this digitalization has also made the communication easier with the patient and other clinicians as they can also understand and visualize the treatment plan. It is now much easier to achieve a straighter and healthier smile because of digital orthodontics. Hence this review is mainly based on the softwares which are currently available for orthodontic purposes.

Research paper thumbnail of Comparsion of the shear bond strength of ceramic brackets bonded to porcelain fused metal crowns and metal free ceramic crowns with and without silane coupling agent- an in vitro study

IP Indian Journal of Orthodontics and Dentofacial Research, 2020

The aim of this study is to evaluate and compare the shear bond strength of ceramic brackets bond... more The aim of this study is to evaluate and compare the shear bond strength of ceramic brackets bonded to porcelain fused metal crowns and metal free ceramic crowns with and without silane coupling agent. 40 metal free zirconia crowns and 40 PFM crowns were fabricated with glazed surfaces according to the manufacturer’s instructions for the study purpose. The samples were divided in two groups A and B and each group was subdivided into two subgroups (A1, A2) and (B1, B2) Twenty metal free ceramic crowns were etched with 9% buffered HF acid gel for 2 minutes, thoroughly washed and air dried. Relyx ceramic primer (silane coupling agent) was applied to the treated surface.20 porcelain fused metal crowns were etched with 9% buffered HF acid gel for 2 minutes, thoroughly washed and air dried. Relyx ceramic primer (silane coupling agent) was applied to the treated surfaceThe shear bond strength of ceramic brackets bonded to porcelain fused metal crowns and metal free ceramic crowns with and ...

Research paper thumbnail of 3D approaches to model the tumor microenvironment of pancreatic cancer

Research paper thumbnail of An Exploration of Electrocatalytic Analysis and Antibacterial Efficacy of Electrically Conductive Poly (D-Glucosamine)/Graphene Oxide Bionanohybrid

Carbohydrate Polymers, 2020

The diversification of environment congenial and conservative nanocomposites is prestigious becau... more The diversification of environment congenial and conservative nanocomposites is prestigious because of increasing contamination in biota. Poly (D-glucosamine), a natural biopolymer is contemplated as a promising biodegradable polysaccharide for various applications mainly in food packaging, bone substitutes, and water filtration. The drawback of poly (D-glucosamine) is nadir mechanical strength and high hydrophilicity which could be amended by the introduction of graphene oxide (GO) nanoparticles (shows excellent load transfer). Homogeneous distribution and well dispersion of GO nanoparticles in poly (D-glucosamine) matrix have been concluded by SEM investigation. Inclusions of 1% GO into the biopolymer matrix results in enhancement of 83.21 MPa of tensile strength in contrary to pristine poly (D-glucosamine). It can be elucidated that increment in properties is due to the crosslinking reaction takes place between the amine and epoxide moieties that exist within poly (D-glucosamine) matrix and GO respectively. The thermal stability of nanocomposites has been increased on addition of nanofiller confirmed by TGA analysis. The resultant nanocomposites were examined for antimicrobial screening against various contagious bacterial strains for packaging applications. Electrochemical characteristics and capacitive investigation of the composites were also studied using cyclic voltammetry and impedance (EIS) respectively. EIS elucidated that the nanocomposite modified electrode exhibited good capacitance behaviour with the Bode phase angle (-45°) which proves the candidates have good capacitive properties. The electrocatalytic properties are found to be diffusion controlled in alkaline medium with good electrical conductivity with low resistance. It is envisioned that the resultant bionanocomposite has potential applications in packaging industry.

Research paper thumbnail of Insulin-copper quantum clusters preparation and receptor targeted bioimaging

Colloids and Surfaces B: Biointerfaces, 2020

Protein embedded fluorescence quantum clusters (QCs) have received a great amount of interest amo... more Protein embedded fluorescence quantum clusters (QCs) have received a great amount of interest among the researchers because of their high aqueous solubility, stability, cost efficiency, and target specificity. Considerable advancement has happened in making functional quantum clusters with target specificity. This work reports the simple synthesis of insulin protected copper quantum clusters (ICuQCs) and its receptor-targeted bioimaging applications. The preparation of copper quantum clusters (CuQCs) was done simply by one-pot synthesis method by changing the pH of the insulin protein firstly to 10.5 basic pH than physiological pH. At physiological pH, the mixture incubated in oven 37 ⁰C at 240 rpm has been developed to process initially polydisperse, non-fluorescent, and unstable CuDs into monodispersed (∼2-3 nm), highly fluorescent, and extremely stable ICuQCs in the same phase (aqueous) using insulin as protein. HRTEM image show uniform distribution of CuDs within the protein matrix. Metal ion binding site prediction and docking server (MIB) results show that chain B of insulin contains 3 templates contains 5 amino acid residues which bind with Cu2+ metal ion. Groove 1 contains GLY8 and HIS10 bind has the highest binding potential towards Cu metal ions. The methodology adopted in this study should largely contribute to the practical applications of this new class of QCs. In view of the protein protection, coupled with direct synthesis and easy functionalization, this hybrid QC-protein system is expected to have numerous optical and bioimaging applications in the future.

Research paper thumbnail of Carbon-Based Nanomaterials as Novel Nanosensors

Journal of Nanomaterials, 2017

Research paper thumbnail of Abstract CT165: Phase II open label trial of minnelide™ in patients with chemotherapy refractory metastatic pancreatic cancer

Clinical Trials, 2019

BackgroundTriptolide and its water-soluble prodrug, Minnelide™, have shown promising activity aga... more BackgroundTriptolide and its water-soluble prodrug, Minnelide™, have shown promising activity against pancreatic ductal adenocarcinoma (PDAC) in both in vitro and in vivo experiments. Triptolide induces apoptosis in pancreatic cancer cells by different pathways, including caspase-dependent apoptotic death and caspase -independent autophagic death. It inhibits the activity of the TFIIH general transcription factor complex and modulates the transcriptional landscape of both the stroma and cancer cell compartments. In the epithelial tumour compartment, triptolide down-regulates key transcription factors such as c-MYC. In the phase I clinical trial of Minnelide™ significant activity in highly refractory metastatic pancreatic carcinoma was observed. Hence we undertook this study in patients with chemotherapy refractory metastatic PDAC. MethodsEligibility criteria include stage IV PDAC that has progressed on standard chemotherapy, Karnofsky performance status ≥ 70%, and measurable disease. Planned sample size is up to 35 patients with interim analysis after the first 18 evaluable patients, aiming for at least a 20% difference in DCR (10% v 30%). Minnelide™ 0.67 mg/m2 is administered intravenously over 30 minutes on days 1-21, followed by a 7 day rest period in a 28 day cycle. Exploratory objectives include: analysis of tumor texture on radiologic scans as a non-invasive biomarker for response, as well as analyses of paired tumour biopsies for changes in immune cell infiltration, stromal activation, chromatin accessibility, phopshoproteomics and metabolism. # NCT03117920The trial opened 4/2017 and as of 12/2018, 18 patients have been treated. Supported by SU2C, Cancer Research UK, Lustgarten Foundation Citation Format: David Propper, Haiyong Han, Daniel Von Hoff, Erkut Borazanci, Tannishtha Reya, Jonathan Ghergurovich, Irina Pshenichnaya, Corina Antal, Rachel Condjella, Shreya Sharma, Peter O9Dwyer, Trevor Littlewood, Hitendra Patel, Ashok Saluja, Mohana Velagapudi, Lifeng Yang, Michael Downes, Ronald Evans, Gerard Evan. Phase II open label trial of minnelide™ in patients with chemotherapy refractory metastatic pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT165.

Research paper thumbnail of Does Vitamin D Supplementation Improve Glycaemic Control In Children With Type 1 Diabetes Mellitus? - A Randomized Controlled Trial

Journal of clinical and diagnostic research : JCDR, 2017

Vitamin D endocrine system is a potential immune system modulator and has been implicated in the ... more Vitamin D endocrine system is a potential immune system modulator and has been implicated in the pathogenesis of several autoimmune diseases including Type 1 Diabetes Mellitus (T1DM). Studies have demonstrated an inverse risk relationship between T1DM and Vitamin D levels and also, shown a reduced risk of the disease with its supplementation. To evaluate the role of Vitamin D as an adjuvant in improving glycaemic control and residual pancreatic beta-cell function. Primary outcome was the mean change in HbA1c levels over a period of six months. This double-blinded randomized controlled trial was done in a tertiary care hospital, Southern India and included 52 children aged 1-18 years with T1DM, with 26 participants each in the intervention and standard of care arm. Oral Vitamin D therapy was administered once a month for six months in addition to insulin in intervention arm while only insulin was continued for other arm. Plasma HbA1c, serum 25-Hydroxy vitamin D (25OHD), insulin dose ...

Research paper thumbnail of A comparative evaluation of natural and artificial scaffolds in regenerative endodontics: A clinical study

Saudi Endodontic Journal, 2016

Aim: To evaluate and compare the regenerative potential of natural autologous scaffolds (blood cl... more Aim: To evaluate and compare the regenerative potential of natural autologous scaffolds (blood clot and platelet rich fibrin [PRF]) with artificial scaffolds (commercially available collagen and poly-lactic-co-glycolic acid [PLGA] polymer) in inducing apexogenesis in necrotic immature permanent teeth. Materials and Methods: Necrotic immature permanent maxillary incisors with or without radiographic evidence of periapical lesion were included. Access opening was done under rubber dam isolation. Canal disinfection was done using minimal instrumentation, copious irrigation, and triple antibiotic paste as interappointment medicament for 4 weeks. After 4 weeks, asymptomatic teeth were divided into four groups on the basis of scaffolds used for revascularization procedure: Group I (blood clot); Group II (PRF); Group III (collagen); Group IV (PLGA). The clinical and radiographic evaluations of teeth were done at 6 and 12 months after the procedure and compared with baseline records. Result: Clinically, patients were completely asymptomatic throughout the study period. Radiographically, all cases showed improvement in terms of periapical healing, apical closure, root lengthening, and dentinal wall thickening. PRF and collagen gave better results than blood clot and PLGA in terms of periapical healing, apical closure, and dentinal wall thickening. Conclusion: Revascularization procedure is more effective and conservative over apexification in the management of necrotic immature permanent teeth. This study has shown that PRF and collagen are better scaffolds than blood clot and PLGA for inducing apexogenesis in immature necrotic permanent teeth.

Research paper thumbnail of Expression/localization patterns of sirtuins (SIRT1, SIRT2, and SIRT7) during progression of cervical cancer and effects of sirtuin inhibitors on growth of cervical cancer cells

Tumor Biology, 2015

Sirtuins belong to the family of class III histone deacetylases; its role in neoplasia is controv... more Sirtuins belong to the family of class III histone deacetylases; its role in neoplasia is controversial as both tumor-suppressive and promoting functions have been reported. There are very few reports available, where expressions of sirtuin isoforms are comprehensively analyzed during neoplasia. Therefore, in the present study, the expression of SIRT1, SIRT2, and SIRT7 during different stages of cervical cancer progression was analyzed. The normal cervical epithelium showed feeble expression of sirtuin isoforms, SIRT1, SIRT2, and SIRT7. A significant increase in SIRT1 expression was noted in the cytoplasm as well as in the nucleus of proliferative layers of cervical epithelium in squamous intraepithelial lesions (SIL); however, in the squamous cell carcinomas (SCC), a heterogeneous pattern of SIRT1 expression varying from low to high was noted. A progressive increase in the expression of both SIRT2 and SIRT7 was noted during cancer progression in the following order: normal < preneoplasia < cancer. Cervical cancer cell lines, HeLa and SiHa, showed higher levels of SIRT1 and SIRT2 in comparison to the immortalized cell counterpart, HaCaT. Specific inhibitors of SIRT1 (Ex527) and SIRT2 (AGK2) impaired the growth of the cervical cancer cells, SiHa, but not of the HaCaT cells. SIRT1 inhibition caused cell death, while SIRT2 inhibition resulted in cell cycle arrest. In conclusion, we report the overexpression of SIRT2 and SIRT7 proteins in cervical cancer and suggest probable application of sirtuin inhibitors as therapeutic targets. Further, a specific increase in the levels of SIRT1 in intraepithelial lesion makes it a promising candidate for identification of preneoplastic changes.

Research paper thumbnail of Magnetic bead purification of enveloped alphavirus and flavivirus

MethodsX, 2021

Virus production is an essential part of virology. The quality of virus preparation, in terms of ... more Virus production is an essential part of virology. The quality of virus preparation, in terms of purification and yield, can affect the outcome of experiments. Purified virus is critical for assays, as contamination from cell culture supernatants may affect results. Purified virus is also needed for vaccine preparations. The traditional process of gradient purification of virus is time consuming, with multiple steps spanning over days, and produces significant amounts of biohazard waste. Developing a more efficient alternative that provides a purified virus product is highly desirable. In this study, we performed magnetic bead purification of Zika virus (ZIKV) and Mayaro virus (MAYV) with the Mag4C LV kit from OZ Biosciences. Currently, this kit is only indicated for use with lentiviruses and retroviruses. We found that we were able to successfully concentrate and purify both ZIKV and MAYV using the kit. Therefore, we concluded that the Mag4C LV kit provides a quick and simple alternative to traditional virus purification methods.•Our protocol is customized by using an alphavirus (MAYV) and flavivirus (ZIKV). This method has not been previously used for these viruses.

Research paper thumbnail of Softwares in Orthodontics- a Review

INTERNATIONAL JOURNAL OF SCIENTIFIC RESEARCH, 2021

There has been a huge advancement in the orthodontic technology that enables an orthodontist to p... more There has been a huge advancement in the orthodontic technology that enables an orthodontist to plan the treatment precisely and this digitalization has also made the communication easier with the patient and other clinicians as they can also understand and visualize the treatment plan. It is now much easier to achieve a straighter and healthier smile because of digital orthodontics. Hence this review is mainly based on the softwares which are currently available for orthodontic purposes.

Research paper thumbnail of Comparsion of the shear bond strength of ceramic brackets bonded to porcelain fused metal crowns and metal free ceramic crowns with and without silane coupling agent- an in vitro study

IP Indian Journal of Orthodontics and Dentofacial Research, 2020

The aim of this study is to evaluate and compare the shear bond strength of ceramic brackets bond... more The aim of this study is to evaluate and compare the shear bond strength of ceramic brackets bonded to porcelain fused metal crowns and metal free ceramic crowns with and without silane coupling agent. 40 metal free zirconia crowns and 40 PFM crowns were fabricated with glazed surfaces according to the manufacturer’s instructions for the study purpose. The samples were divided in two groups A and B and each group was subdivided into two subgroups (A1, A2) and (B1, B2) Twenty metal free ceramic crowns were etched with 9% buffered HF acid gel for 2 minutes, thoroughly washed and air dried. Relyx ceramic primer (silane coupling agent) was applied to the treated surface.20 porcelain fused metal crowns were etched with 9% buffered HF acid gel for 2 minutes, thoroughly washed and air dried. Relyx ceramic primer (silane coupling agent) was applied to the treated surfaceThe shear bond strength of ceramic brackets bonded to porcelain fused metal crowns and metal free ceramic crowns with and ...

Research paper thumbnail of 3D approaches to model the tumor microenvironment of pancreatic cancer

Research paper thumbnail of An Exploration of Electrocatalytic Analysis and Antibacterial Efficacy of Electrically Conductive Poly (D-Glucosamine)/Graphene Oxide Bionanohybrid

Carbohydrate Polymers, 2020

The diversification of environment congenial and conservative nanocomposites is prestigious becau... more The diversification of environment congenial and conservative nanocomposites is prestigious because of increasing contamination in biota. Poly (D-glucosamine), a natural biopolymer is contemplated as a promising biodegradable polysaccharide for various applications mainly in food packaging, bone substitutes, and water filtration. The drawback of poly (D-glucosamine) is nadir mechanical strength and high hydrophilicity which could be amended by the introduction of graphene oxide (GO) nanoparticles (shows excellent load transfer). Homogeneous distribution and well dispersion of GO nanoparticles in poly (D-glucosamine) matrix have been concluded by SEM investigation. Inclusions of 1% GO into the biopolymer matrix results in enhancement of 83.21 MPa of tensile strength in contrary to pristine poly (D-glucosamine). It can be elucidated that increment in properties is due to the crosslinking reaction takes place between the amine and epoxide moieties that exist within poly (D-glucosamine) matrix and GO respectively. The thermal stability of nanocomposites has been increased on addition of nanofiller confirmed by TGA analysis. The resultant nanocomposites were examined for antimicrobial screening against various contagious bacterial strains for packaging applications. Electrochemical characteristics and capacitive investigation of the composites were also studied using cyclic voltammetry and impedance (EIS) respectively. EIS elucidated that the nanocomposite modified electrode exhibited good capacitance behaviour with the Bode phase angle (-45°) which proves the candidates have good capacitive properties. The electrocatalytic properties are found to be diffusion controlled in alkaline medium with good electrical conductivity with low resistance. It is envisioned that the resultant bionanocomposite has potential applications in packaging industry.

Research paper thumbnail of Insulin-copper quantum clusters preparation and receptor targeted bioimaging

Colloids and Surfaces B: Biointerfaces, 2020

Protein embedded fluorescence quantum clusters (QCs) have received a great amount of interest amo... more Protein embedded fluorescence quantum clusters (QCs) have received a great amount of interest among the researchers because of their high aqueous solubility, stability, cost efficiency, and target specificity. Considerable advancement has happened in making functional quantum clusters with target specificity. This work reports the simple synthesis of insulin protected copper quantum clusters (ICuQCs) and its receptor-targeted bioimaging applications. The preparation of copper quantum clusters (CuQCs) was done simply by one-pot synthesis method by changing the pH of the insulin protein firstly to 10.5 basic pH than physiological pH. At physiological pH, the mixture incubated in oven 37 ⁰C at 240 rpm has been developed to process initially polydisperse, non-fluorescent, and unstable CuDs into monodispersed (∼2-3 nm), highly fluorescent, and extremely stable ICuQCs in the same phase (aqueous) using insulin as protein. HRTEM image show uniform distribution of CuDs within the protein matrix. Metal ion binding site prediction and docking server (MIB) results show that chain B of insulin contains 3 templates contains 5 amino acid residues which bind with Cu2+ metal ion. Groove 1 contains GLY8 and HIS10 bind has the highest binding potential towards Cu metal ions. The methodology adopted in this study should largely contribute to the practical applications of this new class of QCs. In view of the protein protection, coupled with direct synthesis and easy functionalization, this hybrid QC-protein system is expected to have numerous optical and bioimaging applications in the future.

Research paper thumbnail of Carbon-Based Nanomaterials as Novel Nanosensors

Journal of Nanomaterials, 2017

Research paper thumbnail of Abstract CT165: Phase II open label trial of minnelide™ in patients with chemotherapy refractory metastatic pancreatic cancer

Clinical Trials, 2019

BackgroundTriptolide and its water-soluble prodrug, Minnelide™, have shown promising activity aga... more BackgroundTriptolide and its water-soluble prodrug, Minnelide™, have shown promising activity against pancreatic ductal adenocarcinoma (PDAC) in both in vitro and in vivo experiments. Triptolide induces apoptosis in pancreatic cancer cells by different pathways, including caspase-dependent apoptotic death and caspase -independent autophagic death. It inhibits the activity of the TFIIH general transcription factor complex and modulates the transcriptional landscape of both the stroma and cancer cell compartments. In the epithelial tumour compartment, triptolide down-regulates key transcription factors such as c-MYC. In the phase I clinical trial of Minnelide™ significant activity in highly refractory metastatic pancreatic carcinoma was observed. Hence we undertook this study in patients with chemotherapy refractory metastatic PDAC. MethodsEligibility criteria include stage IV PDAC that has progressed on standard chemotherapy, Karnofsky performance status ≥ 70%, and measurable disease. Planned sample size is up to 35 patients with interim analysis after the first 18 evaluable patients, aiming for at least a 20% difference in DCR (10% v 30%). Minnelide™ 0.67 mg/m2 is administered intravenously over 30 minutes on days 1-21, followed by a 7 day rest period in a 28 day cycle. Exploratory objectives include: analysis of tumor texture on radiologic scans as a non-invasive biomarker for response, as well as analyses of paired tumour biopsies for changes in immune cell infiltration, stromal activation, chromatin accessibility, phopshoproteomics and metabolism. # NCT03117920The trial opened 4/2017 and as of 12/2018, 18 patients have been treated. Supported by SU2C, Cancer Research UK, Lustgarten Foundation Citation Format: David Propper, Haiyong Han, Daniel Von Hoff, Erkut Borazanci, Tannishtha Reya, Jonathan Ghergurovich, Irina Pshenichnaya, Corina Antal, Rachel Condjella, Shreya Sharma, Peter O9Dwyer, Trevor Littlewood, Hitendra Patel, Ashok Saluja, Mohana Velagapudi, Lifeng Yang, Michael Downes, Ronald Evans, Gerard Evan. Phase II open label trial of minnelide™ in patients with chemotherapy refractory metastatic pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT165.

Research paper thumbnail of Does Vitamin D Supplementation Improve Glycaemic Control In Children With Type 1 Diabetes Mellitus? - A Randomized Controlled Trial

Journal of clinical and diagnostic research : JCDR, 2017

Vitamin D endocrine system is a potential immune system modulator and has been implicated in the ... more Vitamin D endocrine system is a potential immune system modulator and has been implicated in the pathogenesis of several autoimmune diseases including Type 1 Diabetes Mellitus (T1DM). Studies have demonstrated an inverse risk relationship between T1DM and Vitamin D levels and also, shown a reduced risk of the disease with its supplementation. To evaluate the role of Vitamin D as an adjuvant in improving glycaemic control and residual pancreatic beta-cell function. Primary outcome was the mean change in HbA1c levels over a period of six months. This double-blinded randomized controlled trial was done in a tertiary care hospital, Southern India and included 52 children aged 1-18 years with T1DM, with 26 participants each in the intervention and standard of care arm. Oral Vitamin D therapy was administered once a month for six months in addition to insulin in intervention arm while only insulin was continued for other arm. Plasma HbA1c, serum 25-Hydroxy vitamin D (25OHD), insulin dose ...

Research paper thumbnail of A comparative evaluation of natural and artificial scaffolds in regenerative endodontics: A clinical study

Saudi Endodontic Journal, 2016

Aim: To evaluate and compare the regenerative potential of natural autologous scaffolds (blood cl... more Aim: To evaluate and compare the regenerative potential of natural autologous scaffolds (blood clot and platelet rich fibrin [PRF]) with artificial scaffolds (commercially available collagen and poly-lactic-co-glycolic acid [PLGA] polymer) in inducing apexogenesis in necrotic immature permanent teeth. Materials and Methods: Necrotic immature permanent maxillary incisors with or without radiographic evidence of periapical lesion were included. Access opening was done under rubber dam isolation. Canal disinfection was done using minimal instrumentation, copious irrigation, and triple antibiotic paste as interappointment medicament for 4 weeks. After 4 weeks, asymptomatic teeth were divided into four groups on the basis of scaffolds used for revascularization procedure: Group I (blood clot); Group II (PRF); Group III (collagen); Group IV (PLGA). The clinical and radiographic evaluations of teeth were done at 6 and 12 months after the procedure and compared with baseline records. Result: Clinically, patients were completely asymptomatic throughout the study period. Radiographically, all cases showed improvement in terms of periapical healing, apical closure, root lengthening, and dentinal wall thickening. PRF and collagen gave better results than blood clot and PLGA in terms of periapical healing, apical closure, and dentinal wall thickening. Conclusion: Revascularization procedure is more effective and conservative over apexification in the management of necrotic immature permanent teeth. This study has shown that PRF and collagen are better scaffolds than blood clot and PLGA for inducing apexogenesis in immature necrotic permanent teeth.

Research paper thumbnail of Expression/localization patterns of sirtuins (SIRT1, SIRT2, and SIRT7) during progression of cervical cancer and effects of sirtuin inhibitors on growth of cervical cancer cells

Tumor Biology, 2015

Sirtuins belong to the family of class III histone deacetylases; its role in neoplasia is controv... more Sirtuins belong to the family of class III histone deacetylases; its role in neoplasia is controversial as both tumor-suppressive and promoting functions have been reported. There are very few reports available, where expressions of sirtuin isoforms are comprehensively analyzed during neoplasia. Therefore, in the present study, the expression of SIRT1, SIRT2, and SIRT7 during different stages of cervical cancer progression was analyzed. The normal cervical epithelium showed feeble expression of sirtuin isoforms, SIRT1, SIRT2, and SIRT7. A significant increase in SIRT1 expression was noted in the cytoplasm as well as in the nucleus of proliferative layers of cervical epithelium in squamous intraepithelial lesions (SIL); however, in the squamous cell carcinomas (SCC), a heterogeneous pattern of SIRT1 expression varying from low to high was noted. A progressive increase in the expression of both SIRT2 and SIRT7 was noted during cancer progression in the following order: normal < preneoplasia < cancer. Cervical cancer cell lines, HeLa and SiHa, showed higher levels of SIRT1 and SIRT2 in comparison to the immortalized cell counterpart, HaCaT. Specific inhibitors of SIRT1 (Ex527) and SIRT2 (AGK2) impaired the growth of the cervical cancer cells, SiHa, but not of the HaCaT cells. SIRT1 inhibition caused cell death, while SIRT2 inhibition resulted in cell cycle arrest. In conclusion, we report the overexpression of SIRT2 and SIRT7 proteins in cervical cancer and suggest probable application of sirtuin inhibitors as therapeutic targets. Further, a specific increase in the levels of SIRT1 in intraepithelial lesion makes it a promising candidate for identification of preneoplastic changes.