Luis Pérez - Academia.edu (original) (raw)

Papers by Luis Pérez

Cancer genetics, 2011

Epidemiological evidence suggests that genetic factors, such as variants in cancer suppressor gen... more Epidemiological evidence suggests that genetic factors, such as variants in cancer suppressor genes, may play an important role in the etiology of cervical carcinoma. TP53 is an outstanding cell cycle regulator, mutated in most human cancers, and RNASEL is thought to be involved in antiviral and apoptotic responses. To determine whether TP53 Arg72Pro and RNASEL Arg462Gln polymorphisms are associated with susceptibility to cervical cancer, a case-control study of 98 cancer patients and 123 healthy controls was conducted. Cervical samples were genotyped for both polymorphisms by pyrosequencing technology. The association between cervical cancer risk and the studied SNPs was evaluated by logistic regression, and potential gene-gene interactions were studied by Multifactor Dimensionality Reduction analysis. In the single-locus analysis, only the heterozygous TP53 Arg72Pro genotype was significantly associated with the risk of developing a cervical carcinoma, while the RNASEL polymorphis...

Proceedings, 2019

This research aims to improve adherence to dietetic-nutritional treatment using state-of-the-art ... more This research aims to improve adherence to dietetic-nutritional treatment using state-of-the-art RGB-D sensor and virtual reality (VR) technology. Recent studies show that adherence to treatment can be improved by using multimedia technologies which impact on the body awareness of patients. However, there are no studies published to date using 3D data and VR technologies for this purpose. This paper describes a system capable of obtaining the complete 3D model of a body with high accuracy and a realistic visualization for 2D and VR devices to be used for studying the effect of 3D technologies on adherence to obesity treatment.

World Journal of Gastroenterology, 2006

AIM: To evaluate the potential association between p53 codon 72 polymorphism and sporadic colorec... more AIM: To evaluate the potential association between p53 codon 72 polymorphism and sporadic colorectal adenocarcinoma development, and human papillomavirus (HPV) infection. METHODS: One-hundred and nine controls and 53 patients with colon cancer from the city of La Plata, Argentina were analyzed. p53 codon 72 genotypes and HPV infection were identifi ed using allele-specifi c polymerase chain reaction and nested polymerase chain reaction, respectively. RESULTS: The differences in the distribution of p53 codon 72 polymorphism between the cases and controls were statistically significant. The arginine allele had a prevalence of 0.65 in controls and 0.77 in cases. The corresponding odds ratio for the homozygous arginine genotype was 2.08 (95% CI , 1.06-4.05; P <0.05). Lack of association was found between p53 polymorphism and HPV infection in the set of adenocarcinomas. CONCLUSION: The fi ndings of the present study indicate that p53 codon 72 arginine homozygous genotype may represent a genetic predisposing factor for colon cancer development. However, further studies are needed in order to elucidate the role of p53 codon 72 polymorphism in colorectal cancer.

Apoptosis is the major component of programmed cell death, an essential process in embryogenesis,... more Apoptosis is the major component of programmed cell death, an essential process in embryogenesis, tissue turnover and proper function of the immune system. Lack of appropriate control is thought to play an important role in several pathologies, such as autoimmune diseases, AIDS and cancer. In malignant tumors, cells gradually acquire resistance to apoptosis and, moreover, develop mechanisms that could induce death cell in immune cells. Emerging interest has given to the Fas/Fas Ligand interaction, a system that triggers the extrinsic pathway of the apoptosis process. Polymorphisms on Fas and FasL have been extensively described. Single nucleotide polymorphisms located in the promoter region of these genes have been found to be related to differential levels of expression. This review discusses the information published on Fas/Fas Ligand polymorphisms and its effect on human cancers, and also presents new data regarding the impact of Fas-670A/G and FasL-844T/C polymorphisms in a cerv...

Journal of Virological Methods, 2005

The aim of the present study was to evaluate the first void urine (FVU) as a non-invasive samplin... more The aim of the present study was to evaluate the first void urine (FVU) as a non-invasive sampling method for HPV detection and genotyping in a high-risk population. Men presenting with HPV associated penile lesions or HPV positive partners attending a urological department in La Plata, Argentina were enrolled for HPV detection and genotyping. DNA from 185 first-void urine samples was evaluated for the presence of HPV by nested polymerase chain reaction using MY09/11 and GP05/06 primers. The viral genotype was analyzed by means of the single-stranded conformation polymorphisms (SSCP) method. Seventy-three percent (135/185) of the FVU specimens were positive for HPV-DNA. The viral prevalence in patients with HPV-DNA positive partners was 68.8% (77/112), and 79.5% (58/73) of patients with penile lesions were found to be HPV positive. The most frequent viral type was HPV-11 (26.7%), followed by HPV-6 (23%), HPV-16 (21.5%), HPV-18 (6%), and HPV-31 (4.4%). In this study, 11.1% (15/135) of the HPV positive specimens were double infections. These results indicate that high-risk HPVs can be found in clinical lesions in a high percentage (43.8%), as simple or double infections. In this sense, the male population represents an important reservoir for the virus and may play a role in the transmission and perpetuation of the infection in the general population. The method described below provides a tool for detection and typing of HPV-DNA using samples obtained by non-invasive techniques and thus easy to obtain.

Colorectal Disease, 2005

The aim of the present work was to evaluate the presence of human papillomavirus genotypes in mal... more The aim of the present work was to evaluate the presence of human papillomavirus genotypes in malignant and normal mucosa of the colon and rectum in order to determine if a relationship exists between HPV infection and colon neoplasms. Thirty normal colon tissues and 54 sporadic adenocarcinomas were screened for HPV positivity using nested-PCR. Detection of viral types 6, 11, 16, 18, 33, 34 and 51 was performed by the LIS-SSCP (Low Ionic Strength-Single Strand Conformational Polymorphism) procedure. Significant differences in high risk HPV infection were found between normal samples and adenocarcinomas (P < 0.001). Among the cases, an inverse association between HPV infection and Dukes staging was also found (P = 0.020). Finally, there was no significant association between HPV and some classical clinicopathological features, although a gradient of infection form rectum to cecum was evident. The present study demonstrates that HPV may infect the glandular mucosa of the colon and suggests a possible association between HPV and colorectal cancer.

Pathology oncology research : POR, 2010

The aim of the present study is to determine the presence and molecular integrity of high-risk HP... more The aim of the present study is to determine the presence and molecular integrity of high-risk HPV types in colorectal adenocarcinomas and to assess whether viral DNA is related to common proto-oncogene alterations, such as k-ras mutations and c-myc gene amplification, in colorectal cancer. Seventy-five colorectal adenocarcinomas were screened for HPV infection using nested-PCR (MY09/11-GP5+/6+). HPV typing was performed by type-specific PCR for HPV 16 and HPV 18 DNA. Unidentified samples were subsequently sequenced to determine the viral genotype. The physical status of HPV was determined by a nested PCR approach for type-specific E2 sequences. C-myc amplification was assessed by co-amplification with β-globin as control locus, and mutation in k-ras codons 12 and 13 by ARMS-PCR. Overall, HPV was detected in thirty-three colorectal specimens (44%). HPV 16 was the prevalent type (16/75), followed by HPV 18 (15/75), HPV 31 (1/75) and HPV 66 (1/75). E2 disruption was detected in 56.3% ...

Pathology oncology research : POR, 2013

Human Papillomavirus (HPV) is the main cause of cervical cancer and its precursor lesions. Transf... more Human Papillomavirus (HPV) is the main cause of cervical cancer and its precursor lesions. Transformation may be induced by several mechanisms, including oncogene activation and genome instability. Individual differences in DNA damage recognition and repair have been hypothesized to influence cervical cancer risk. The aim of this study was to evaluate whether the double strand break gene polymorphisms XRCC2 R188H…

Annals of Internal Medicine, 1984

Because few clinicians have access to laboratories offering cell culture confirmation of suspecte... more Because few clinicians have access to laboratories offering cell culture confirmation of suspected Chlamydia trachomatis genital infections, we evaluated a diagnostic method in which fluorescein-conjugated monoclonal antibodies were used to directly identify C. ...

PLOS ONE, 2015

The diversity of the five single nucleotide polymorphisms located in genes of the TP53 pathway (T... more The diversity of the five single nucleotide polymorphisms located in genes of the TP53 pathway (TP53, rs1042522; MDM2, rs2279744; MDM4, rs1563828; USP7, rs1529916; and LIF, rs929271) were studied in a total of 282 individuals belonging to Quechua, Aymara, Chivay, Cabanaconde, Yanke, Taquile, Amantani, Anapia, Uros, Guarani Ñandeva, and Guarani Kaiowá populations, characterized as Native American or as having a high level (> 90%) of Native American ancestry. In addition, published data pertaining to 100 persons from five other Native American populations (Surui, Karitiana, Maya, Pima, and Piapoco) were analyzed. The populations were classified as living in high altitude ( 2,500 m) or in lowlands (< 2,500 m). Our analyses revealed that alleles USP7-G, LIF-T, and MDM2-T showed significant evidence that they were selected for in relation to harsh environmental variables related to high altitudes. Our results show for the first time that alleles of classical TP53 network genes have been evolutionary co-opted for the successful human colonization of the Andes.

World journal of gastroenterology : WJG, Jan 7, 2006

To evaluate the potential association between p53 codon 72 polymorphism and sporadic colorectal a... more To evaluate the potential association between p53 codon 72 polymorphism and sporadic colorectal adenocarcinoma development,and human papillomavirus (HPV) infection. One-hundred and nine controls and 53 patients with colon cancer from the city of La Plata, Argentina were analyzed. p53 codon 72 genotypes and HPV infection were identified using allele-specific polymerase chain reaction and nested polymerase chain reaction, respectively. The differences in the distribution of p53 codon 72 polymorphism between the cases and controls were statistically significant. The arginine allele had a prevalence of 0.65 in controls and 0.77 in cases. The corresponding odds ratio for the homozygous arginine genotype was 2.08 (95% CI, 1.06-4.05; P<0.05). Lack of association was found between p53 polymorphism and HPV infection in the set of adenocarcinomas. The findings of the present study indicate that p53 codon 72 arginine homozygous genotype may represent a genetic predisposing factor for colon ...

Colorectal Disease, 2005

Objective The aim of the present work was to evaluate the presence of human papillomavirus genoty... more Objective The aim of the present work was to evaluate the presence of human papillomavirus genotypes in malignant and normal mucosa of the colon and rectum in order to determine if a relationship exists between HPV infection and colon neoplasms.

Cancer genetics, 2011

International Journal of Gynecological Pathology, 2006

The aim of the present study was to determine that prevalence of herpes simplex virus (HSV) type ... more The aim of the present study was to determine that prevalence of herpes simplex virus (HSV) type 1 and 2 in cervical samples from Argentine women and to assess the role of HSV-2 in cervical cancer. A sample of 79 normal and 200 neoplastic cervical tissues (35 invasive cervical carcinomas, 75 high-grade squamous intraepithelial lesions, 79 low-grade squamous intraepithelial lesions and 11 abnormal squamous cells of undermined significance) was analyzed for herpes simplex and human papillomavirus DNA using the polymerase chain reaction method. Viral genotyping was performed by single strand conformation polymorphisms and restriction fragment length polymorphisms. The overall prevalence of HSV was 21.5% in controls and 29% in cases. Among women with normal cytology, herpes simplex prevalence in HPV positive (20.8%) women was approximately the same as in negative (21.8%) women. HPV-and age-adjusted ORs of high-grade squamous intraepithelial lesions and invasive cervical carcinomas for HSV-2 were 1.4 (p = 0.6) and 1.6 (p = 0.5), respectively. The obtained results indicated that herpes simplex virus may not be involved in cervical cancer development. Future investigations are needed to provided conclusive evidence on the role of this pathogen in cervical cancer.