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Copyright of TIP Revista Especializada en Ciencias Químico-Biológicas is the property of Universidad Nacional Autonoma de Mexico, Facultad de Estudios Superiores Zaragoza and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background We have developed an oligonucleotide microarray (genosensor) utilizing a double tandem hybridization technique to search for 9 point mutations located in the most frequently altered codons of the TP53 gene. Isolated and multiplexed PCR products, 108 and 92 bp long, from exons 7 and 8, respectively, were obtained from 24 different samples. Single-stranded target DNA was then prepared from isolated or multiplexed PCR products, through cyclic DNA synthesis. Independent ssDNA's were annealed with the corresponding pairs of labeled stacking oligonucleotides to create partially duplex DNA having a 7-nt gap, which contains the sequence that will be interrogated by the capture probes forming double tandem hybridization. In the case of multiplexed ssPCR products, only two stacking oligonucleotides were added per target, therefore the gap for the PCR products having two consecutive codons to be interrogated in exon 7 was 12 nt long, so only single tandem hybridization was produced with these respective probes. Results 18 codon substitutions were found by DNA sequencing. In 13 of them a perfect correlation with the pattern of hybridization was seen (In 5 no signal was seen with the wt probe while a new signal was seen with the appropriate mutant probe, and in 8 more, as expected, no signal was seen with any probe due to the absence of the corresponding probe in the array). In 3 other cases a mutation was falsely suggested by the combination of the absence of the wild type signal along with a false signal in the other probe. In the other 2 cases the presence of the mutation was not detected due to the production of a false hybridization signal with the wild type probe. In both cases (false mutation or no mutation detected) relatively stable mismatched target/probe duplexes should be formed. These problems could be avoided by the addition of probes to improve the performance of the array. Conclusion Our results demonstrate that a simple TP53 microarray employing short (7-mer) probes, used in combination with single or double tandem hybridization approach and a simple or multiplex target preparation method, can identify common TP53 missense mutations from a variety of DNA sources with good specificity.

Copyright of Revista Medica del IMSS is the property of Direccion de Prestaciones Medicas - IMSS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Worldwide, breast cancer (BrCa) is currently the leading cause of deaths associated to malignant lesions in adult women. Given that some studies have mentioned that peritumoral adipocytes may contribute to breast carcinogenesis, present work sought to quantitative evaluate the morphometry of these cells in a group of adult women. Three thousand six hundred sixty four breast adipocytes, that came from biopsies of a group of adult females with different types of breast carcinomas (ductal, lobular, and mixed) and one with normal tissues, were evaluated through an image analysis (IA) process regarding six morphometric descriptors: area (A), perimeter (P), Feret diameter (FD), aspect ratio (AR), roundness factor (RF), and fractal dimension of cellular contour (FDC). Data showed that the adipocytes of the normal tissues group were bigger (A: 3398 ± 2331 µm2, P: 239 ± 83 µm, and FD: 79.9 ± 24.5 µm) than those from BrCa samples (A: 2860 ± 1933 µm2, P: 214 ± 66 µm, and FD: 73.2 ± 22.5 µm), and presented a more irregular contour (FDC of 1.370 ± 0.037 for normal group and of 1.335 ± 0.049 for the oncologic one). Moreover, it could be accounted that adipocytes of mixed carcinomas were largest (FD: 75.1 ± 22.4 µm) than those of lobular lesions (FD: 61.6 ± 22.6 µm), while the adipocytes of ductal carcinomas were the most oval (AR: 1.421 ± 0.524) and roughest (FDC: 1.324 ± 0.050) cells. IA results suggest that BrCa lesions can be categorized through a quantitative morphometric evaluation of peritumoral adipocytes. These findings could let the development of an analytical tool to help the Pathologist to enhance the accuracy of the oncologic diagnose. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Sanidad Militar is the property of Direccion General de Sanidad Secretaria de la Defensa Nacional and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hodgkin lymphoma (HL) is a rare neoplasm of the lymphatic system, in which inflammation and allelic variants in cytokines have been proposed as etiological factors. Epstein-Barr virus infection is often associated as a risk factor in HL and since cytokines are involved in the humoral response to viral infection. Our aim was to study the association between single nucleotide polymorphisms (SNPs) located in the tumor necrosis factor (TNF) gene (− 376G> A, − 238G> A and 581G> A) in a sample of Mexican patients (56 cases) and their susceptibility to develop HL, comparing these SNPs among healthy individuals (127 controls). Frequencies for TNF − 238G> A and TNF 581G> A showed no significant differences between cases and controls. However, the proportion of cases with the GA genotype of − 376 SNP showed a significant difference as compared to controls, odds ratio = 4.41 (95% confidence interval: 1.21-16.6), p = 0.02. We found that in this group of patients from Mexico the SNP − 376G> A in TNF shows an association with higher risk for HL. [ABSTRACT FROM AUTHOR]

Copyright of Revista Medica del IMSS is the property of Direccion de Prestaciones Medicas - IMSS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: We have developed an oligonucleotide microarray (genosensor) utilizing a double tandem hybridization technique to search for 9 point mutations located in the most frequently altered codons of the TP53 gene. Isolated and multiplexed PCR products, 108 and 92 bp long, from exons 7 and 8, respectively, were obtained from 24 different samples. Single-stranded target DNA was then prepared from isolated or multiplexed PCR products, through cyclic DNA synthesis. Independent ssDNA's were annealed with the corresponding pairs of labeled stacking oligonucleotides to create partially duplex DNA having a 7-nt gap, which contains the sequence that will be interrogated by the capture probes forming double tandem hybridization. In the case of multiplexed ssPCR products, only two stacking oligonucleotides were added per target, therefore the gap for the PCR products having two consecutive codons to be interrogated in exon 7 was 12 nt long, so only single tandem hybridization was produced with these respective probes. Results: 18 codon substitutions were found by DNA sequencing. In 13 of them a perfect correlation with the pattern of hybridization was seen (In 5 no signal was seen with the wt probe while a new signal was seen with the appropriate mutant probe, and in 8 more, as expected, no signal was seen with any probe due to the absence of the corresponding probe in the array). In 3 other cases a mutation was falsely suggested by the combination of the absence of the wild type signal along with a false signal in the other probe. In the other 2 cases the presence of the mutation was not detected due to the production of a false hybridization signal with the wild type probe. In both cases (false mutation or no mutation detected) relatively stable mismatched target/probe duplexes should be formed. These problems could be avoided by the addition of probes to improve the performance of the array. Conclusion: Our results demonstrate that a simple TP53 microarray employing short (7-mer) probes, used in combination with single or double tandem hybridization approach and a simple or multiplex target preparation method, can identify common TP53 missense mutations from a variety of DNA sources with good specificity. [ABSTRACT FROM AUTHOR]

Introduction: Cervical cancer and cervical intraepithelial neoplasia (CIN) require a careful selection of conventional and complementary therapies. The inclusion of dietary supplements within the aforementioned treatments set the tone within treatments. However, there are no reports of what kind of supplements could be used to provide a better response to the disease in these patients. Objective: In this review, we analyze clinical trials of the past 20 years that evaluated dietary supplements on this population, with the objective to raise awareness on which of them are viable to be administered. Methods: We performed a search for clinical trials that used a dietary supplement in women with cervical cancer and some degree of NIC analyzing them how to use the supplement, the conventional treatment, deficiency of the nutrient or compound to be evaluated, the characteristics of the population, the clinical trial and the supplement, as well as dosage and their effects. Results: Twenty were in total the number of studies reviewed. The articles were classified according to the nature of the supplement: Retinoids, vitamin E, probiotics, indoles, multivitamin, folic acid and selenium. Conclusion: Some supplements were found to be effective in the treatment of cervical cancer and CIN. However, their effect depends on specific factors of the disease. The correct management of dietary supplements is an effective aid to help the patient with cancer and therefore, it is important to define what complementary therapies can be used for this population. [ABSTRACT FROM AUTHOR]

Introducción: las lesiones intraepiteliales escamosas (LIE) son un estado de transición hacia el cáncer cervicouterino (CaCu) y un déficit de micronutrientes puede acelerar este proceso. Por ello, determinar la existencia de este déficit y conocer qué factores se asocian permitiría una posible prevención en esta población de riesgo.Objetivo: determinar la presencia de alguna deficiencia de micronutrientes involucrados en el proceso anticancerígeno y asociar este déficit con hábitos y factores demográficos en pacientes con LIE de Ciudad Juárez, Chihuahua, México.Métodos:en un estudio transversal analítico fueron seleccionadas 102 pacientes con LIE. Se realizó una encuesta dietaría (recordatorio de 24 horas) para estimar la ingesta de micronutrientes. La deficiencia fue determinada con un consumo < 75% de la ingesta diaria recomendada o sugerida (IDR o IDS) en México. Algunos hábitos y factores demográficos fueron obtenidos mediante la entrevista con la paciente. Se realizó un modelo de regresión logística para asociar la presencia de deficiencia con factores que afectan a la ingesta o incrementan el requerimiento de micronutrientes.Resultados:el retinol, ácido fólico, zinc, vitaminas C y E, considerados como micronutrientes en el proceso anticancerígeno del CaCu, se encontraron por debajo del 75% de la IDR. Aquellas mujeres con sobrepeso, obesidad y amas de casa se asociaron significativamente con la deficiencia de micronutrientes.Conclusión: el sobrepeso, la obesidad y la ocupación han sido asociados para presentar deficiencias de micronutrientes en este estudio. Estas variables convergen en una posible inseguridad alimentaria, la cual podría asociarse al incremento de incidencia de CaCu en México. [ABSTRACT FROM AUTHOR]

Important anatomical-functional differences are found between hypothalamus of male and female rats which appear and are regulated by sexual steroids during the critical hypothalamic development period. This is especially true of estradiol's involvement. In this study, several genetic differences between male and female rats were assessed. These differences are related to gene expression to apoptosis, neurogenesis and synaptogenesis in four-hour old rats. The effect of early administration of testosterone propionate (TP) to female rats, and tamoxifen (Tx) to male rats on the gene pattern expression was reviewed using DNA microarray analysis combined with qPRC. Gene expression differences were found in female and male hypothalamus. In female rats, there was greater gene expression related to apoptosis: IL-24, Smpd3, Tpa, Pp4, Map3k1, Pge and Naca3; to cell differentiation, Neurod2, Zic1 and Epo; and to synapsis and the control of the cell cycle, Syt7, Tgfbr1, Ptf1a and Cox2. It was also shown that administration of Tx to male rats caused similar genetic expression to that of female rats, while TP given to female rats was not as effective in modifying gene expression. These results clearly show that in the absence of estradiol in female rats, genes favoring cell death are expressed which may explain size differences in certain hypothalamic areas in male and female rats. This may be due too to the fact that in male hypothalamus, certain areas are provided with greater estradiol alpha type receptors and therefore with manifest neuroprotection and other areas with beta receptors where apoptosis predominates. [ABSTRACT FROM AUTHOR]

Background: We are currently witnessing a worldwide event caused by the pandemic outbreak derived from the new SARS-CoV-2 virus, which requires the generation of knowledge. Due to its novelty, many hypotheses and theories are discussed daily regarding the origin of this new virus. Several studies are focused on demonstrating how similar it is to other viruses., Objective: To highlight the differences of SARS-CoV-2 with other SARS viruses, from a comparative genomics analysis, and determine if these can be attributed to manipulation events., Material and Methods: Complete genomes of two SARS viruses were downloaded, along with other six of human coronaviruses, and 16 of SARS-type coronaviruses. These were analyzed using the BLAST Ring Image Generator tool; afterwards, the evident differences were examined by MAFFT and BLAST programs., Results: High identity was observed in fragments of the mammalian SARS-like genomes with the SARS-CoV-1 and SARS-CoV-2 genomes, identifying three main nucleotide differences, in the ORF1ab nsp3 region gene, in the receptor recognition S gene, and in the ORF8 gene, with which the SARS-type strains of mammals can be separated into the SARS-CoV-1 and SARS-CoV-2 type., Conclusion: The complete SARS-CoV-2 genome has high identity with mammalian SARS-type strains, which is why its most probable appearance could be the result of natural evolution., (Copyright: © 2020 Revista Medica del Instituto Mexicano del Seguro Social.)

In the efforts to explain COVID-19 pathophysiology, studies are being carried out on the correspondence between the expression of SARS-CoV-2 cell receptors and viral sequences. ACE2, CD147 and TMPRSS2 receptors expression could indicate poorly explored potential infection targets. For the genomic analysis of SARS-CoV-2 receptors, using BioGPS information was decided, which is a portal that centralizes genetic annotation resources, in combination with that of The Human Protein Atlas, the largest portal of human transcriptome and proteome data. We also reviewed the most recent articles on the subject. RNA and viral receptor proteins expression was observed in numerous anatomical sites, which partially coincides with the information reported in the literature. High expression in testicular cells markedly stood out, and it would be therefore important ruling out whether this anatomical site is a SARS-CoV-2 reservoir; otherwise, germ cell damage, as it is observed in infections with other RNA viruses, should be determined., (Copyright: © 2020 Permanyer.)