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Vladimir Costa Silva - One of the best experts on this subject based on the ideXlab platform.

  • Genetic polymorphism of calcium-sensing receptor in women with breast cancer
    Medical Oncology, 2018
    Co-Authors: Larysse Maira Campos-verdes, João Paulo Silva-sampaio, Danylo Rafhael Costa-silva, Victor Alves Oliveira, Airton Mendes Conde Junior, Vladimir Costa Silva, Airlane Pereira Alencar, Viriato Campelo, Pedro Vitor Lopes-costa, Luiz Henrique Gebrim
    Abstract:

    Breast cancer is a disease of unknown etiology, whose major risk factors are genetic alterations. Polymorphism of the calcium-sensing receptor (CaSR) has been a focus of some recent studies, due to a probable association with breast cancer risk and tumor aggressiveness. A relationship between polymorphic rs17251221 variant of the CaSR gene, and allele G (considered a gain-of-function mutation) and breast cancer risk has been stressed, despite the paucity of studies found in the literature. The present study involved 137 women (69 women with breast cancer—case; and 68 controls without breast cancer) who had 3 ml of peripheral blood drawn for DNA study. Genomic DNA was extracted from leukocytes by Genotyping Technique with real-time polymerase chain reaction. The AG genotype (rs17251221) was present in 13 women (18.84%) from the case group and in 8 (11.76%) women from the control group ( p  = 0.3434), while the GG genotype (rs17251221) did not occur in any group. In contrast, no statistically significant difference was observed between the AG genotype of variant rs17251221 in premenopausal case and control women ( p  = 0.71). There was also no statistically significant difference between postmenopausal case and control patients ( p  = 0.6851). In the current study, CaSR gene polymorphism of SNP variant rs17251221 did not show any statistically significant association with breast cancer, in both premenopausal and postmenopausal women.

  • Insulin-like growth factor 1 gene polymorphism in women with breast cancer
    Medical Oncology, 2017
    Co-Authors: Danylo Rafhael Costa-silva, Larysse Maira Campos-verdes, João Paulo Silva-sampaio, Airlane Pereira Alencar, Maria Barros-oliveira, Rafael Soares Borges, Carla Solange Escorcio-dourado, Luana Mota Martins, Edmund Chada Baracat, Vladimir Costa Silva
    Abstract:

    Breast cancer is a disease of unknown etiology; however, the major risk factors are genetic alterations. Studies have demonstrated an association between insulin-like growth factor 1 (IGF-1) gene polymorphism and cell proliferation and reduced apoptosis, in addition to its role in breast cancer growth and aggressiveness. Two polymorphic variants of the IGF-1 gene are highlighted in association with breast cancer, rs6220 and rs7136446, although controversy exists as to this relationship. The current study included 137 women (68 breast cancer cases and 69 controls without breast cancer) who had 3 ml of peripheral blood drawn for the study of genomic DNA extracted from leukocytes using the Genotyping Technique by real-time polymerase chain reaction. The CC genotype (rs7136446) was present in 4 women (5.9%) from the case group and in 2 (3.0%) women from the control group ( p  = 0.67), while the GG genotype (rs6220) occurred in 8 (11.5%) women from the case group and in 5 (7.2%) women from the control group ( p  = 0.75). No statistically significant difference was observed between the CC genotype of variant rs7136446 in premenopausal case and control women ( p  = 0.31), thus as there was also no significant difference between case and control postmenopausal women ( p  = 1.00). Concerning the GG genotype of rs6220, it occurred in 6 (14.2%) premenopausal case and 4 (8%) control women ( p  = 0.71) and no difference was found in postmenopausal women ( p  = 1.00). In the current study, IGF-1 gene polymorphism of SNP variants rs6220 and rs7136446 had no statistically significant association with breast cancer, both in premenopausal and postmenopausal women.

Eric N. Villegas - One of the best experts on this subject based on the ideXlab platform.

  • development and evaluation of an off the slide Genotyping Technique for identifying giardia cysts and cryptosporidium oocysts directly from us epa method 1623 slides
    Journal of Applied Microbiology, 2013
    Co-Authors: Michael W. Ware, Scott P. Keely, Eric N. Villegas
    Abstract:

    Aims This study developed and systematically evaluated performance and limit of detection of an off-the-slide Genotyping procedure for both Cryptosporidium oocysts and Giardia cysts. Methods and Results Slide standards containing flow-sorted (oo)cysts were used to evaluate the off-the-slide Genotyping procedure by microscopy and PCR. Results show approximately 20% of cysts and oocysts are lost during staining. Although transfer efficiency from the slide to the PCR tube could not be determined by microscopy, it was observed that the transfer process aided in the physical lysis of the (oo)cysts likely releasing DNA. PCR detection rates for a single event on a slide were 44% for Giardia and 27% for Cryptosporidium, and a minimum of five cysts and 20 oocysts are required to achieve a 90% PCR detection rate. A Poisson distribution analysis estimated the relative PCR target densities and limits of detection, it showed that 18 Cryptosporidium and five Giardia replicates are required for a 95% probability of detecting a single (oo)cyst on a slide. Conclusions This study successfully developed and evaluated recovery rates and limits of detection of an off-the-slide Genotyping procedure for both Cryptosporidium and Giardia (oo)cysts from the same slide. Significance and Impact of the Study This off-the-slide Genotyping Technique is a simple and low cost tool that expands the applications of US EPA Method 1623 results by identifying the genotypes and assemblages of the enumerated Cryptosporidium and Giardia. This additional information will be useful for microbial risk assessment models and watershed management decisions.

  • Development and evaluation of an off‐the‐slide Genotyping Technique for identifying Giardia cysts and Cryptosporidium oocysts directly from US EPA Method 1623 slides
    Journal of Applied Microbiology, 2013
    Co-Authors: Michael W. Ware, Scott P. Keely, Eric N. Villegas
    Abstract:

    Aims This study developed and systematically evaluated performance and limit of detection of an off-the-slide Genotyping procedure for both Cryptosporidium oocysts and Giardia cysts. Methods and Results Slide standards containing flow-sorted (oo)cysts were used to evaluate the off-the-slide Genotyping procedure by microscopy and PCR. Results show approximately 20% of cysts and oocysts are lost during staining. Although transfer efficiency from the slide to the PCR tube could not be determined by microscopy, it was observed that the transfer process aided in the physical lysis of the (oo)cysts likely releasing DNA. PCR detection rates for a single event on a slide were 44% for Giardia and 27% for Cryptosporidium, and a minimum of five cysts and 20 oocysts are required to achieve a 90% PCR detection rate. A Poisson distribution analysis estimated the relative PCR target densities and limits of detection, it showed that 18 Cryptosporidium and five Giardia replicates are required for a 95% probability of detecting a single (oo)cyst on a slide. Conclusions This study successfully developed and evaluated recovery rates and limits of detection of an off-the-slide Genotyping procedure for both Cryptosporidium and Giardia (oo)cysts from the same slide. Significance and Impact of the Study This off-the-slide Genotyping Technique is a simple and low cost tool that expands the applications of US EPA Method 1623 results by identifying the genotypes and assemblages of the enumerated Cryptosporidium and Giardia. This additional information will be useful for microbial risk assessment models and watershed management decisions.

Newton Banupriya - One of the best experts on this subject based on the ideXlab platform.

  • modified low cost snp Genotyping Technique using cycle threshold ct melting temperature tm values in allele specific real time pcr
    Indian Journal of Medical Research, 2015
    Co-Authors: Benet Bosco D Dhas, Subash Chandra Parija, Hiasindh A Ashmi, Vishnu B Bhat, Newton Banupriya
    Abstract:

    Single nucleotide polymorphisms (SNPs) are predominantly used in various fields of biology starting from evolutionary studies to disease diagnosis/prognosis. Several methods have been used for genotypic analysis, though the search for a cost-effective, potential Technique which can be implemented in patient care is still not available. Though TaqMan Genotyping is considered the most sensitive method1, but due to its high cost, it is not applicable for routine patient care in developing countries with poor diagnostic settings. Hence, there is a need to have an efficient Genotyping Technique which can be applied in routine diagnostic settings for handling large number of samples within a few hours and at low cost. Allele-specific PCR coupled with amplicon melt curve analysis had been used in Genotyping for more than a decade. It was found to be the most cost-effective means of Genotyping for various diseases2. In this method, Genotyping is carried out using two forward primers each specific to one allele and a common reverse primer. After amplification, the amplicons are melted and the alleles are discriminated by the melting temperature (Tm). In 1997, microvolume fluorometer integrated with thermal cycler was used to analyze the amplicon melt curve using SYBR Green-I dye3. Later with the advancement of real-time PCR, the same allele-specific PCR was made rapid with high sensitive amplicon melt curve analysis. In order to make the assay further sensitive, different strategies like usage of unlabelled probes4, multiplex primers5 and energy-transfer-labelled primers6 have been used. However, these methods require significant optimization protocols and technical expertise which make these non-applicable in low resource settings. In this study, two SNPs (one transition and one transversion) of human origin were analysed to prove the efficiency and cost-effectiveness of allele-specific real-time PCR coupled with amplicon melt curve analysis in Genotyping by incorporating GC-tail and 3’ mismatch in the primer sequence. Allelic discrimination and zygosity testing were also made easier with combined assessment of cycle threshold (Ct) and Tm values.

  • Modified low cost SNP Genotyping Technique using cycle threshold (Ct) & melting temperature (Tm) values in allele specific real-time PCR.
    Indian Journal of Medical Research, 2015
    Co-Authors: D. Benet Bosco Dhas, A Hiasindh Ashmi, B. Vishnu Bhat, Subash Chandra Parija, Newton Banupriya
    Abstract:

    Single nucleotide polymorphisms (SNPs) are predominantly used in various fields of biology starting from evolutionary studies to disease diagnosis/prognosis. Several methods have been used for genotypic analysis, though the search for a cost-effective, potential Technique which can be implemented in patient care is still not available. Though TaqMan Genotyping is considered the most sensitive method1, but due to its high cost, it is not applicable for routine patient care in developing countries with poor diagnostic settings. Hence, there is a need to have an efficient Genotyping Technique which can be applied in routine diagnostic settings for handling large number of samples within a few hours and at low cost. Allele-specific PCR coupled with amplicon melt curve analysis had been used in Genotyping for more than a decade. It was found to be the most cost-effective means of Genotyping for various diseases2. In this method, Genotyping is carried out using two forward primers each specific to one allele and a common reverse primer. After amplification, the amplicons are melted and the alleles are discriminated by the melting temperature (Tm). In 1997, microvolume fluorometer integrated with thermal cycler was used to analyze the amplicon melt curve using SYBR Green-I dye3. Later with the advancement of real-time PCR, the same allele-specific PCR was made rapid with high sensitive amplicon melt curve analysis. In order to make the assay further sensitive, different strategies like usage of unlabelled probes4, multiplex primers5 and energy-transfer-labelled primers6 have been used. However, these methods require significant optimization protocols and technical expertise which make these non-applicable in low resource settings. In this study, two SNPs (one transition and one transversion) of human origin were analysed to prove the efficiency and cost-effectiveness of allele-specific real-time PCR coupled with amplicon melt curve analysis in Genotyping by incorporating GC-tail and 3’ mismatch in the primer sequence. Allelic discrimination and zygosity testing were also made easier with combined assessment of cycle threshold (Ct) and Tm values.

Danylo Rafhael Costa-silva - One of the best experts on this subject based on the ideXlab platform.

  • Genetic polymorphism of calcium-sensing receptor in women with breast cancer
    Medical Oncology, 2018
    Co-Authors: Larysse Maira Campos-verdes, João Paulo Silva-sampaio, Danylo Rafhael Costa-silva, Victor Alves Oliveira, Airton Mendes Conde Junior, Vladimir Costa Silva, Airlane Pereira Alencar, Viriato Campelo, Pedro Vitor Lopes-costa, Luiz Henrique Gebrim
    Abstract:

    Breast cancer is a disease of unknown etiology, whose major risk factors are genetic alterations. Polymorphism of the calcium-sensing receptor (CaSR) has been a focus of some recent studies, due to a probable association with breast cancer risk and tumor aggressiveness. A relationship between polymorphic rs17251221 variant of the CaSR gene, and allele G (considered a gain-of-function mutation) and breast cancer risk has been stressed, despite the paucity of studies found in the literature. The present study involved 137 women (69 women with breast cancer—case; and 68 controls without breast cancer) who had 3 ml of peripheral blood drawn for DNA study. Genomic DNA was extracted from leukocytes by Genotyping Technique with real-time polymerase chain reaction. The AG genotype (rs17251221) was present in 13 women (18.84%) from the case group and in 8 (11.76%) women from the control group ( p  = 0.3434), while the GG genotype (rs17251221) did not occur in any group. In contrast, no statistically significant difference was observed between the AG genotype of variant rs17251221 in premenopausal case and control women ( p  = 0.71). There was also no statistically significant difference between postmenopausal case and control patients ( p  = 0.6851). In the current study, CaSR gene polymorphism of SNP variant rs17251221 did not show any statistically significant association with breast cancer, in both premenopausal and postmenopausal women.

  • Insulin-like growth factor 1 gene polymorphism in women with breast cancer
    Medical Oncology, 2017
    Co-Authors: Danylo Rafhael Costa-silva, Larysse Maira Campos-verdes, João Paulo Silva-sampaio, Airlane Pereira Alencar, Maria Barros-oliveira, Rafael Soares Borges, Carla Solange Escorcio-dourado, Luana Mota Martins, Edmund Chada Baracat, Vladimir Costa Silva
    Abstract:

    Breast cancer is a disease of unknown etiology; however, the major risk factors are genetic alterations. Studies have demonstrated an association between insulin-like growth factor 1 (IGF-1) gene polymorphism and cell proliferation and reduced apoptosis, in addition to its role in breast cancer growth and aggressiveness. Two polymorphic variants of the IGF-1 gene are highlighted in association with breast cancer, rs6220 and rs7136446, although controversy exists as to this relationship. The current study included 137 women (68 breast cancer cases and 69 controls without breast cancer) who had 3 ml of peripheral blood drawn for the study of genomic DNA extracted from leukocytes using the Genotyping Technique by real-time polymerase chain reaction. The CC genotype (rs7136446) was present in 4 women (5.9%) from the case group and in 2 (3.0%) women from the control group ( p  = 0.67), while the GG genotype (rs6220) occurred in 8 (11.5%) women from the case group and in 5 (7.2%) women from the control group ( p  = 0.75). No statistically significant difference was observed between the CC genotype of variant rs7136446 in premenopausal case and control women ( p  = 0.31), thus as there was also no significant difference between case and control postmenopausal women ( p  = 1.00). Concerning the GG genotype of rs6220, it occurred in 6 (14.2%) premenopausal case and 4 (8%) control women ( p  = 0.71) and no difference was found in postmenopausal women ( p  = 1.00). In the current study, IGF-1 gene polymorphism of SNP variants rs6220 and rs7136446 had no statistically significant association with breast cancer, both in premenopausal and postmenopausal women.

Larysse Maira Campos-verdes - One of the best experts on this subject based on the ideXlab platform.

  • Genetic polymorphism of calcium-sensing receptor in women with breast cancer
    Medical Oncology, 2018
    Co-Authors: Larysse Maira Campos-verdes, João Paulo Silva-sampaio, Danylo Rafhael Costa-silva, Victor Alves Oliveira, Airton Mendes Conde Junior, Vladimir Costa Silva, Airlane Pereira Alencar, Viriato Campelo, Pedro Vitor Lopes-costa, Luiz Henrique Gebrim
    Abstract:

    Breast cancer is a disease of unknown etiology, whose major risk factors are genetic alterations. Polymorphism of the calcium-sensing receptor (CaSR) has been a focus of some recent studies, due to a probable association with breast cancer risk and tumor aggressiveness. A relationship between polymorphic rs17251221 variant of the CaSR gene, and allele G (considered a gain-of-function mutation) and breast cancer risk has been stressed, despite the paucity of studies found in the literature. The present study involved 137 women (69 women with breast cancer—case; and 68 controls without breast cancer) who had 3 ml of peripheral blood drawn for DNA study. Genomic DNA was extracted from leukocytes by Genotyping Technique with real-time polymerase chain reaction. The AG genotype (rs17251221) was present in 13 women (18.84%) from the case group and in 8 (11.76%) women from the control group ( p  = 0.3434), while the GG genotype (rs17251221) did not occur in any group. In contrast, no statistically significant difference was observed between the AG genotype of variant rs17251221 in premenopausal case and control women ( p  = 0.71). There was also no statistically significant difference between postmenopausal case and control patients ( p  = 0.6851). In the current study, CaSR gene polymorphism of SNP variant rs17251221 did not show any statistically significant association with breast cancer, in both premenopausal and postmenopausal women.

  • Insulin-like growth factor 1 gene polymorphism in women with breast cancer
    Medical Oncology, 2017
    Co-Authors: Danylo Rafhael Costa-silva, Larysse Maira Campos-verdes, João Paulo Silva-sampaio, Airlane Pereira Alencar, Maria Barros-oliveira, Rafael Soares Borges, Carla Solange Escorcio-dourado, Luana Mota Martins, Edmund Chada Baracat, Vladimir Costa Silva
    Abstract:

    Breast cancer is a disease of unknown etiology; however, the major risk factors are genetic alterations. Studies have demonstrated an association between insulin-like growth factor 1 (IGF-1) gene polymorphism and cell proliferation and reduced apoptosis, in addition to its role in breast cancer growth and aggressiveness. Two polymorphic variants of the IGF-1 gene are highlighted in association with breast cancer, rs6220 and rs7136446, although controversy exists as to this relationship. The current study included 137 women (68 breast cancer cases and 69 controls without breast cancer) who had 3 ml of peripheral blood drawn for the study of genomic DNA extracted from leukocytes using the Genotyping Technique by real-time polymerase chain reaction. The CC genotype (rs7136446) was present in 4 women (5.9%) from the case group and in 2 (3.0%) women from the control group ( p  = 0.67), while the GG genotype (rs6220) occurred in 8 (11.5%) women from the case group and in 5 (7.2%) women from the control group ( p  = 0.75). No statistically significant difference was observed between the CC genotype of variant rs7136446 in premenopausal case and control women ( p  = 0.31), thus as there was also no significant difference between case and control postmenopausal women ( p  = 1.00). Concerning the GG genotype of rs6220, it occurred in 6 (14.2%) premenopausal case and 4 (8%) control women ( p  = 0.71) and no difference was found in postmenopausal women ( p  = 1.00). In the current study, IGF-1 gene polymorphism of SNP variants rs6220 and rs7136446 had no statistically significant association with breast cancer, both in premenopausal and postmenopausal women.