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1.
Sci Rep ; 13(1): 17933, 2023 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-37863936

RESUMEN

According to WHO statistics, breast cancer (BC) disease represents about 2.3 million diagnosed and 685,000 deaths globally. Regarding histological classification of BC, the Estrogen (ER) and Progesterone (PR) receptors negative-expression cancer, named Triple-Negative BC (TNBC), represents the most aggressive type of this disease, making it a challenge for drug discovery. In this context, our research group, applying a well-established Virtual Screening (VS) protocol, in addition to docking and molecular dynamics simulations studies, yielded two ligands identified as 6 and 37 which were chemically synthesized and evaluated on MCF-7 and MDA-MB-231 cancer cell lines. Strikingly, 37 assayed on MDA-MB-231 (a TNBC cell model) depicted an outstanding value of 18.66 µM much lower than 65.67 µM yielded by Gossypol Bcl-2 inhibitor whose main disadvantage is to produce multiple toxic effects. Highlighted above, enforce the premise of the computational tools to find new therapeutic options against the most aggressive forms of breast cancer, as the results herein showed.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama/patología , Antineoplásicos/uso terapéutico , Estrógenos/farmacología , Simulación de Dinámica Molecular , Línea Celular Tumoral , Proliferación Celular
2.
Microorganisms ; 11(8)2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37630674

RESUMEN

Citrobacter werkmanii is an emerging and opportunistic human pathogen found in developing countries and is a causative agent of wound, urinary tract, and blood infections. The present study conducted comparative genomic analyses of a C. werkmanii strain collection from diverse geographical locations and sources to identify the relevant virulence and antimicrobial resistance genes. Pangenome analyses divided the examined C. werkmanii strains into five distinct clades; the subsequent classification identified genes with functional roles in carbohydrate and general metabolism for the core genome and genes with a role in secretion, adherence, and the mobilome for the shell and cloud genomes. A maximum-likelihood phylogenetic tree with a heatmap, showing the virulence and antimicrobial genes' presence or absence, demonstrated the presence of genes with functional roles in secretion systems, adherence, enterobactin, and siderophore among the strains belonging to the different clades. C. werkmanii strains in clade V, predominantly from clinical sources, harbored genes implicated in type II and type Vb secretion systems as well as multidrug resistance to aminoglycoside, beta-lactamase, fluoroquinolone, phenicol, trimethoprim, macrolides, sulfonamide, and tetracycline. In summary, these comparative genomic analyses have demonstrated highly pathogenic and multidrug-resistant genetic profiles in C. werkmanii strains, indicating a virulence potential for this commensal and opportunistic human pathogen.

3.
Curr Microbiol ; 79(12): 385, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36329340

RESUMEN

Mosquito-borne diseases such as malaria and dengue are global severe public health threats. Due to the lack of efficient control methods, alternative approaches to decreasing arboviral transmitted diseases are prioritized to reduce morbidity and mortality in every endemic region. Mosquito midgut bacteria play an essential role in physiological development, fitness, and the arthropods´ vectorial capacity. Bacteriophages are viruses that infect bacteria and are considered a promising biocontrol method by eliminating midgut microbiota that plays an essential role in mosquitoes´ health. Here, we isolate and identify 22 bacteria from mosquito´s midgut belonging to the genera Mesobacillus, Enterobacter, Klebsiella, Microbacterium, Micrococcus, Pantoea, Serratia, and Staphylococcus, mainly. Twelve phages with lytic activity against Enterobacter, Klebsiella, and Pantoea were also isolated. All 12 phages showed a double-stranded DNA genome, ranging from 36,790 to 149,913 bp, and were taxonomically classified as members of the Drexlerviridae family, Molineuxvirinae, Studiervirinae, and Vequintavirinae subfamilies. Open reading frames associated with phage structure, packing, host lysis, DNA metabolism, and additional functions were predicted in all 12 phage genomes, while tRNAs were predicted in five phage genomes. In addition, the life cycle was predicted as virulent for the 12 phages, and no antibiotic resistance, virulence, allergenic, or lysogenic genes were found in either genome. These findings suggest that the 12 phages have biocontrol potentials; however, it is necessary to elucidate specific bacterial host's roles and then the phages' ability to serve as effective vector control.


Asunto(s)
Aedes , Bacteriófagos , Pantoea , Animales , Bacteriófagos/genética , Aedes/microbiología , Mosquitos Vectores , Genómica
4.
Infect Genet Evol ; 106: 105380, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36283634

RESUMEN

Escherichia coli is a leading cause of human enteric diseases worldwide. The rapid and accurate causal agent identification to a particular source represents a crucial step in the establishment of safety and health measures in the affected human populations and would thus provide insights into the relationship of traits that may contribute for pathogen persistence in a particular reservoir. The objective of the present study was to characterize over two hundred E. coli strains from different isolation sources in Mexico by conducting a correspondence analysis to explore associations with the detected phylogenetic groups. The results indicated that E. coli strains, recovered from distinct sources in Mexico, were classified into phylogroups B1 (35.8%), A (27.8%), and D (12.3%) and were clustered to particular clades according to the predicted phylogroups. The results from correspondence analysis showed that E. coli populations from distinct sources in Mexico, belonging to different phylogroups, were not dispersed randomly and were associated with a particular isolation source. Phylogroup A was strongly associated with human sources, and the phylogroup B1 showed a significant relationship with food sources. Additionally, phylogroup D was also related to human sources. Phylogroup B2 was associated with herbivorous and omnivorous mammals. Moreover, common virulence genes in the examined E. coli strains, assigned to all phylogroups, were identified as essential markers for survival and invasion in the host. Although virulence profiles varied among the detected phylogroups, E. coli strains belonging to phylogroup D, associated with humans, were found to contain the largest virulence gene repertoire conferring for persistence and survival in the host. In summary, these findings provide fundamental information for a better characterization of pathogenic E. coli, recovered from distinct isolation sources in Mexico and would assist in the development of better tools for identifying potential transmission routes of contamination.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli , Animales , Humanos , Filogenia , Virulencia/genética , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/patología , Factores de Virulencia/genética , Mamíferos
5.
Exp Gerontol ; 150: 111360, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-33878422

RESUMEN

BACKGROUND AND OBJECTIVES: The excess of body fat and muscle mass loss in adulthood results in sarcopenic obesity, which is associated with disability and poor physical condition. A relationship among obesity, sarcopenia and oxidative stress also has been established. These aspects limit a good muscle function which is crucial in the independence of older women with and without sarcopenic obesity. This study had as objective to design a moderate intensity exercise program for older women with sarcopenic obesity, and to examine its effects on oxidative damage and physical function. We hypothesized that the exercise program will reduce oxidative damage and to improve the physical function of older women with sarcopenic obesity. METHODS: Thirty healthy women (68 ± 5.05 years old) and 30 women with sarcopenic obesity (68.06 ± 5.75 years old) from the Integral Development of the Family rest home participated in the evaluation. The participants underwent evaluations of body composition, physical fitness (timed up-and-go [TUG] test, reaction time, gait speed, flexibility and muscle strength) and oxidative stress (oxidative damage to lipid and protein as well as evaluation of the antioxidant system) before and after of moderate intensity exercise program. The program consisted of warm-up, flexibility; aerobic exercises of moderate intensity (VO2 max and HR max between 60% and 70%); isotonic exercises of low intensity with progressive weight (250 g of initial weight, with increase every two weeks until reaching 750 g of final weight) and global stretching at the end of each section. The program was monitored on a personal basis and undertaken three times a week over three months. RESULTS: In both groups, the program induced a five-fold increase in muscle strength, an increase in flexibility and improvement of fragility parameters (TUG and gait speed) (P ≤ 0.001, respectively). Furthermore, this exercise program decreased oxidative damage and increased antioxidant defense (P ≤ 0.001) to a greater extent in the sarcopenic group. CONCLUSION: It was concluded that moderate intensity exercise is an effective approach to promote changes in body composition, physical fitness and to reduce oxidative damage in older women with and without sarcopenic obesity. These findings might have important implications for the prevention or treatment of sarcopenic obesity in older people.


Asunto(s)
Sarcopenia , Adulto , Anciano , Composición Corporal , Ejercicio Físico , Terapia por Ejercicio , Femenino , Humanos , Fuerza Muscular , Músculo Esquelético/patología , Obesidad/complicaciones , Obesidad/patología , Obesidad/terapia , Estrés Oxidativo , Sarcopenia/patología , Sarcopenia/terapia
6.
Front Comput Neurosci ; 13: 80, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31849630

RESUMEN

Affective human-robot interaction requires lightweight software and cheap wearable devices that could further this field. However, the estimation of emotions in real-time poses a problem that has not yet been optimized. An optimization is proposed for the emotion estimation methodology including artifact removal, feature extraction, feature smoothing, and brain pattern classification. The challenge of filtering artifacts and extracting features, while reducing processing time and maintaining high accuracy results, is attempted in this work. First, two different approaches for real-time electro-oculographic artifact removal techniques are tested and compared in terms of loss of information and processing time. Second, an emotion estimation methodology is proposed based on a set of stable and meaningful features, a carefully chosen set of electrodes, and the smoothing of the feature space. The methodology has proved to perform on real-time constraints while maintaining high accuracy on emotion estimation on the SEED database, both under subject dependent and subject independent paradigms, to test the methodology on a discrete emotional model with three affective states.

7.
Anticancer Agents Med Chem ; 19(6): 760-771, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30451119

RESUMEN

BACKGROUND: Some reports have demonstrated the role of the G Protein-coupled Estrogen Receptor (GPER) in growth and proliferation of breast cancer cells. OBJECTIVE: In an effort to develop new therapeutic strategies against breast cancer, we employed an in silico study to explore the binding modes of tetrahydroquinoline 2 and 4 to be compared with the reported ligands G1 and G1PABA. METHODS: This study aimed to design and filter ligands by in silico studies determining their Lipinski's rule, toxicity and binding properties with GPER to achieve experimental assays as anti-proliferative compounds of breast cancer cell lines. RESULTS: In silico studies suggest as promissory two tetrahydroquinoline 2 and 4 which contain a carboxyl group instead of the acetyl group (as is needed for G1 synthesis), which add low (2) and high hindrance (4) chemical moieties to explore the polar, hydrophobic and hindrance effects. Docking and molecular dynamics simulations of the target compounds were performed with GPER to explore their binding mode and free energy values. In addition, the target small molecules were synthesized and assayed in vitro using breast cancer cells (MCF-7 and MDA-MB-231). Experimental assays showed that compound 2 decreased cell proliferation, showing IC50 values of 50µM and 25µM after 72h of treatment of MCF-7 and MDA-MB-231 cell lines, respectively. Importantly, compound 2 showed a similar inhibitory effect on proliferation as G1 compound in MDA-MB-231 cells, suggesting that both ligands reach the GPER-binding site in a similar way, as was demonstrated through in silico studies. CONCLUSION: A concentration-dependent inhibition of cell proliferation occurred with compound 2 in the two cell lines regardless of GPER.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Quinolinas/farmacología , Receptores de Estrógenos/antagonistas & inhibidores , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Modelos Moleculares , Estructura Molecular , Quinolinas/síntesis química , Quinolinas/química , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Relación Estructura-Actividad , Termodinámica , Células Tumorales Cultivadas
8.
Pregnancy Hypertens ; 10: 22-27, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29153683

RESUMEN

OBJECTIVE: This study sought to determine whether the angiotensin-converting enzyme insertion/deletion (ACE I/D) polymorphism, obesity and oxidative damage are risk factors for the development of preeclampsia in Mexican women. STUDY DESIGN: A total of 66 women with preeclampsia (PE) and 37 women with normal pregnancies (NP) were included in the study. DNA was extracted from whole blood, and the ACE I/D polymorphism was evaluated by polymerase chain reaction. ACE activity and oxidative damage were assessed in plasma. The intergroup comparisons were analyzed by an analysis of variance (ANOVA) with post hoc tests. Hardy-Weinberg equilibrium (HWE) was tested by x2 analysis, odds ratios (OR) were calculated as a measure of the degree of relative risk of preeclampsia, and for correlations, we used Spearman's correlation coefficient. RESULTS: The frequency of the DD genotype was higher in PE (34.84%) than NP (10.82%). The OR of the DD genotype and D allele were associated with a 4.4-fold (CI=95% 2.24-14) and 3-fold (CI=95% 1.69-5.62) increased risk of developing PE, respectively. Major ACE activity in the DD genotype and obesity were features of the PE group; oxidative damage to proteins and a reduction in the activity of the antioxidant system showed a correlation with BMI (p<0.01). CONCLUSION: Our results suggest that ACE I/D polymorphism, high ACE activity, body mass index and oxidative damage may play key roles in the pathogenesis of PE in the Mexican population. Furthermore, these findings could be used as predictive factors of PE.


Asunto(s)
Predisposición Genética a la Enfermedad , Peptidil-Dipeptidasa A/genética , Preeclampsia/genética , Adulto , Estudios de Casos y Controles , Femenino , Hispánicos o Latinos/genética , Humanos , México , Obesidad/complicaciones , Estrés Oxidativo , Polimorfismo Genético , Preeclampsia/etiología , Embarazo , Factores de Riesgo , Adulto Joven
9.
J Sports Med Phys Fitness ; 57(4): 441-447, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26632851

RESUMEN

BACKGROUND: Several studies have demonstrated the protective effects of cocoa consumption, due to its anti-inflammatory and antioxidant properties. Acute exercise induces oxidative stress and causes muscular damage during training. This study was designed to examine the effect of cocoa consumption on the markers of muscle damage, oxidative stress and physical fitness in professional soccer players. METHODS: Fifteen players (15-18 years old) were included in the study. Biochemical parameters, markers of muscle damage and oxidative stress, and physical performance were evaluated before and after cocoa consumption. Biochemical parameters determined the healthy metabolic status of the study group; biomarkers of muscle and oxidative damage were measured in blood to establish muscle and redox status. RESULTS: However, high levels of biomarkers of muscle damage were detected. Interestingly, cocoa consumption decreased the muscle damage biomarkers of CK and LDH by 39.4% and 23.03%, respectively. The redox status was modified by a decrease in oxidative damage (carbonyl groups, 26.31%; thiol groups, 27.52%; MDA, 32.42%) and an increase in total antioxidant capacity (15.98%) and GSH-Px activity (26.37%). In addition, we observed an increase in physical performance by 4% in the Cooper Test. CONCLUSIONS: Our findings suggest that a short period of cocoa consumption could be useful in maintaining a good physical fitness, due to the favourable effects on muscle and redox status in athletes during exhaustive exercise.


Asunto(s)
Antioxidantes/farmacología , Atletas , Rendimiento Atlético/fisiología , Chocolate , Estrés Oxidativo/efectos de los fármacos , Aptitud Física/fisiología , Fútbol/fisiología , Adolescente , Biomarcadores/metabolismo , Estudios de Casos y Controles , Ejercicio Físico/fisiología , Humanos , Masculino , Oxidación-Reducción/efectos de los fármacos , Adulto Joven
10.
Contemp Oncol (Pozn) ; 19(6): 462-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26843843

RESUMEN

AIM OF THE STUDY: In breast cancer, oestrogen receptor (ER), progesterone receptor (PgR), and HER2 (HER2/Neu) expression status are used to classify neoplasms into subtypes: Luminal A, Luminal B, HER2/Neu type, and Basallike. The aim of the present study was to establish the molecular subtypes of breast cancers and their association with tumour characteristics and reproductive factors in Mexican women. MATERIAL AND METHODS: A total of 1326 biopsies of breast tumour tissues were analysed for ER, PR, and HER2/Neu by immunohistochemistry (IHC). Information regarding age, tumour characteristics, and node involvement profiles were collected. RESULTS: IHC established that the most common subtype of breast cancer was Luminal A (64.93%), followed by Basal-Like (13.88%), Luminal B (12.52%), and HER2/Neu (8.67%). T2-size tumours (> 2 cm but < 5 cm) were present in 47.59% of all patients. Univariate analysis showed that lymph node positivity (p = 0.009), stage (p = 0.013), and placement of the tumour (p = 0.001) were factors associated with breast cancer subtype. CONCLUSIONS: Our data show that IHC is useful for distinguishing different subtypes of breast cancer and that Luminal A is the most common breast cancer subtype in the Mexican population. All subtypes were associated with unfavourable clinicopathological features, suggesting that late diagnosis is an important contributor to high mortality rates in the Mexican population.

11.
Fam Pract ; 32(2): 159-64, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25199520

RESUMEN

BACKGROUND: Pre-diabetes in young people is frequently unrecognized or not treated on time, with the consequent loss of opportunity for diabetes prevention. In Mexico, there is scarce information about the prevalence of pre-diabetes in young adults. OBJECTIVE: To determine the prevalence and risk factors for pre-diabetes in young Mexican adults in primary health care. METHODS: In a cross-sectional study, 288 subjects, aged 18-30 years, from a primary care unit were included. Pre-diabetes was diagnosed (according to the criteria of the American Diabetes Association) as impaired fasting glucose (8-12 hours fasting plasma glucose level: 100-125 mg/dl) or impaired glucose tolerance (140-199 mg/dl after a 2-hour oral glucose tolerance test). RESULTS: Prevalence of pre-diabetes was 14.6% [95% confidence interval (CI): 10.7-19.2], whereas that of diabetes was 2.4% (95% CI: 1.0-4.9). A high proportion of patients had history of obesity, diabetes, hypertension and consumption of tobacco and alcohol. Pre-diabetic patients were older than normoglycaemics (pre-diabetic patients: 26±4 years versus normoglycaemic subjects: 24±3 years, P = 0.003) and had higher body mass index (BMI; pre-diabetic patients: 29.4±6.8 kg/m(2) versus normoglycaemic subjects: 26.8±5.8 kg/m(2); P = 0.009), particularly in the case of men (pre-diabetic men: 29.3±7.0 kg/m(2) versus normoglycaemic men: 26.4±5.1 kg/m(2); P = 0.03). Although waist circumference showed a trend to be higher among pre-diabetics, no significant differences were found according to gender (among males: pre-diabetics: 99.5±18.8 cm versus normoglycaemics: 93.3±14.4 cm, P = 0.09; among females: pre-diabetics: 91.5±13.8 cm versus normoglycaemics: 85.8±15.9 cm, P = 0.16). Only age and BMI were significantly associated with the presence of pre-diabetes. CONCLUSIONS: Almost 15% of these young adults had pre-diabetes. Many modifiable and non-modifiable risk factors were present in these patients, but only age and a higher BMI were independent variables significantly associated with pre-diabetes. Timely interventions in primary health care are needed to prevent or delay the progression to diabetes.


Asunto(s)
Estado Prediabético/epidemiología , Atención Primaria de Salud/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Consumo de Bebidas Alcohólicas/epidemiología , Índice de Masa Corporal , Estudios Transversales , Diabetes Mellitus/epidemiología , Humanos , Hipertensión/epidemiología , México/epidemiología , Obesidad/epidemiología , Estado Prediabético/diagnóstico , Prevalencia , Factores de Riesgo , Fumar/epidemiología , Circunferencia de la Cintura , Adulto Joven
12.
PLoS One ; 8(1): e54056, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23349785

RESUMEN

BACKGROUND: Limited knowledge on the prevalence and distribution of risk factors impairs the planning and implementation of cardiovascular prevention programs in the Latin American and Caribbean (LAC) region. METHODS AND FINDINGS: Prevalence of hypertension, diabetes mellitus, abnormal lipoprotein levels, obesity, and smoking were estimated from individual-level patient data pooled from population-based surveys (1998-2007, n=31,009) from eight LAC countries and from a national survey of the United States (US) population (1999-2004) Age and gender specific prevalence were estimated and age-gender adjusted comparisons between both populations were conducted. Prevalence of diabetes mellitus, hypertension, and low high-density lipoprotein (HDL)-cholesterol in LAC were 5% (95% confidence interval [95% CI]: 3.4, 7.9), 20.2% (95% CI: 12.5, 31), and 53.3% (95% CI: 47, 63.4), respectively. Compared to LAC region's average, the prevalence of each risk factor tended to be lower in Peru and higher in Chile. LAC women had higher prevalence of obesity and low HDL-cholesterol than men. Obesity, hypercholesterolemia, and hypertriglyceridemia were more prevalent in the US population than in LAC population (31 vs. 16.1%, 16.8 vs. 8.9%, and 36.2 vs. 26.5%, respectively). However, the prevalence of low HDL-cholesterol was higher in LAC than in the US (53.3 vs. 33.7%). CONCLUSIONS: Major cardiovascular risk factors are highly prevalent in LAC region, in particular low HDL-cholesterol. In addition, marked differences do exist in this prevalence profile between LAC and the US. The observed patterns of obesity-related risk factors and their current and future impact on the burden of cardiovascular diseases remain to be explained.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Obesidad/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Argentina/epidemiología , Enfermedades Cardiovasculares/sangre , Chile/epidemiología , Colesterol/sangre , HDL-Colesterol/sangre , Colombia/epidemiología , Costa Rica/epidemiología , República Dominicana/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Obesidad/sangre , Perú/epidemiología , Prevalencia , Puerto Rico/epidemiología , Factores de Riesgo , Triglicéridos/sangre , Estados Unidos/epidemiología , Venezuela/epidemiología , Adulto Joven
13.
Onkologie ; 35(10): 570-4, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23038227

RESUMEN

BACKGROUND: Breast cancer is an important cause of cancerrelated death in women. In this pathological condition, arginase plays a role by providing ornithine as a substrate for the biosynthesis of polyamines which are important in tumor progression. The aim of this work was to determine the arginase activity in the plasma and tumors of patients with breast cancer; also, we investigated the relationship between this activity and the presence of the estrogen receptor. PATIENTS AND METHODS: We evaluated the plasma arginase activity levels in 80 women with breast cancer and 42 healthy control subjects. We also measured the arginase levels in 42 breast cancer biopsies and 42 control tissues. RESULTS: The mean activity of arginase in plasma was higher in breast cancer patients (0.78 nM/min/mg protein ± 0.04; p = 0.001) than in healthy volunteers (0.53 nM/ min/mg protein ± 0.04); however, this difference was indicative of patients in the advanced stages of the disease (n = 38, stage III; p < 0.0001). In addition, we did not find a relationship between the estrogen receptor and arginase activity. CONCLUSION: Our results show a higher arginase activity in the plasma of patients in the advanced stages of the disease, suggesting that arginase activity could serve as a possible biological marker of breast cancer progression.


Asunto(s)
Arginasa/sangre , Biomarcadores de Tumor/sangre , Neoplasias de la Mama/sangre , Neoplasias de la Mama/epidemiología , Receptores de Estrógenos/sangre , Adulto , Anciano , Neoplasias de la Mama/diagnóstico , Activación Enzimática , Femenino , Humanos , México/epidemiología , Persona de Mediana Edad , Prevalencia , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad
14.
Arthritis ; 2011: 205904, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22216409

RESUMEN

Ankylosing spondylitis (AS) is not fully explained by inflammatory processes. Clinical, epidemiological, genetic, and course of disease features indicate additional host-related risk processes and predispositions. Collectively, the pattern of predisposition to onset in adolescent and young adult ages, male preponderance, and widely varied severity of AS is unique among rheumatic diseases. However, this pattern could reflect biomechanical and structural differences between the sexes, naturally occurring musculoskeletal changes over life cycles, and a population polymorphism. During juvenile development, the body is more flexible and weaker than during adolescent maturation and young adulthood, when strengthening and stiffening considerably increase. During middle and later ages, the musculoskeletal system again weakens. The novel concept of an innate axial myofascial hypertonicity reflects basic mechanobiological principles in human function, tissue reactivity, and pathology. However, these processes have been little studied and require critical testing. The proposed physical mechanisms likely interact with recognized immunobiological pathways. The structural biomechanical processes and tissue reactions might possibly precede initiation of other AS-related pathways. Research in the combined structural mechanobiology and immunobiology processes promises to improve understanding of the initiation and perpetuation of AS than prevailing concepts. The combined processes might better explain characteristic enthesopathic and inflammatory processes in AS.

15.
Rev Peru Med Exp Salud Publica ; 27(2): 195-200, 2010 Jun.
Artículo en Español | MEDLINE | ID: mdl-21072470

RESUMEN

OBJECTIVE: To estimate the iodine nutritional status in women of childbearing age and to evaluate the intake of salt adequately iodized in their households in Peru. MATERIALS AND METHODS: Cross-sectional study performed with a multistage, probabilistic, cluster sampling that included 1573 households and 2048 women in childbearing age, distributed in five domains (Lima, rest of the coast, rural highlands and jungle area). The use of iodized salt was evaluated in the households and the urinary iodine was evaluated in the childbearing age women. RESULTS: 97.5% (95%CI. 96.7-98.5%) of peruvian households have iodized salt consumption, being it lower in the rural highland (95%) and higher in Lima (100%). The national mean of urinary iodine was 266 µg/L, being it lower in the jungle areas (206 µg/L) and higher in the rest of the coast (302 µg/L), these values are above the level recommended by the World Health Organization in all domains (average higher than 200 µg/L), value that ensures control over the iodine deficiency disorders (IDD). CONCLUSIONS: Control of IDD associated with iodized salt consumption is good, and monitoring of the presence of iodine in salt, particularly in the areas with lowest access, should continue.


Asunto(s)
Yodo/metabolismo , Estado Nutricional , Cloruro de Sodio Dietético/administración & dosificación , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Yodo/administración & dosificación , Persona de Mediana Edad , Perú , Adulto Joven
16.
Ultrason Imaging ; 32(1): 16-32, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20690429

RESUMEN

A novel coded-excitation method, resolution-enhancement compression (REC), increases the axial resolution and the echo signal-to-noise ratio (eSNR) for an ultrasonic imaging system. The REC technique was examined for its ability to improve lesion detectability. The REC technique was used to double the -3-dB fractional pulse-echo bandwidth of an ultrasonic source in both simulations and experiments. The increase in usable bandwidth increased lesion detectability compared to conventional pulsing (CP) techniques and coded excitation using a linear chirp (LC). Lesion detectibility was quantified through lesion signal-to-noise ratio (lSNR), which is a metric that quantifies the ability of an isolated observer to detect a focal lesion against a background. In simulations, a higher lSNR value was observed using the REC technique for lesions ranging in size from 1 mm to 8 mm in diameter. In addition, the eSNR was increased by almost 15 dB. To validate simulation results, a hydrogel-cone phantom was constructed to provide lesions with +6-dB contrast of different sizes. A transducer was scanned perpendicular to the major axis of the cone at different levels to provide lesions of 3, 5 and 8 mm in diameter. The lSNR was estimated for lesions of different sizes and using the three excitation techniques, i.e., CP, LC and REC. In experiments, the lSNR was observed to be higher using the REC technique than the other pulsing techniques. The lSNR scores for REC were higher by 15%, 45% and 40% for the 3, 5 and 8 mm over the other two excitation techniques. The eSNR was increased by 5.7 dB. Therefore, according to the lSNR metric, the improvement in spatial resolution from the REC technique resulted in improved detectability of small lesions.


Asunto(s)
Aumento de la Imagen/métodos , Ultrasonografía/métodos , Simulación por Computador , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Procesamiento de Señales Asistido por Computador , Transductores , Ultrasonografía/instrumentación
17.
Rev. peru. med. exp. salud publica ; 27(2): 195-200, abr.-jun. 2010. tab, graf
Artículo en Español | LILACS, LIPECS | ID: lil-565452

RESUMEN

Objetivo. Estimar el estado nutricional de yodo en mujeres en edad fértil y evaluar la ingesta de sal adecuadamente yodada en sus hogares en el Perú. Materiales y métodos. Estudio transversal realizado con un muestreo probabilístico multietápico por conglomerados que incluyó 1573 hogares y 2048 mujeres en edad fértil, distribuidas en cinco dominios (Lima, resto de costa, sierra rural, sierra urbana y selva). Se evaluó el uso de sal yodada en hogares y el yodo urinario en mujeres en edad fértil. Resultados. El 97,5% (IC95%: 96,7 - 98,5%) de hogares peruanos consumen sal yodada, siendo menor en sierra rural (95%) y mayor en Lima metropolitana (100%). La mediana de yoduria nacional fue de 266 microgramos por litro, siendo menores en la selva (206 microgramos por litro) y mayores en el resto de costa (302 microgramos por litro), estos valores se encuentran por encima del límite recomendado por la Organización Mundial de la Salud en todos los dominios (mediana mayor a 200 microgramos por litro), valor que asegura un control de desórdenes por deficiencia de yodo (DDI). Conclusiones. En control de los DDI por el consumo de sal yodado es bueno, se debe continuar con la vigilancia de la presencia de yodo en la sal, particularmente en las áreas con menor acceso.


Objective. To estimate the iodine nutritional status in women of childbearing age and to evaluate the intake of salt adequately iodized in their households in Peru. Materials and methods. Cross-sectional study performed with a multistage, probabilistic, cluster sampling that included 1573 households and 2048 women in childbearing age, distributed in five domains (Lima, rest of the coast, rural highlands and jungle area). The use of iodized salt was evaluated in the households and the urinary iodine was evaluated in the childbearing age women. Results. 97.5% (95% CI. 96.7-98.5%) of peruvian households have iodized salt consumption, being it lower in the rural highland (95%) and higher in Lima (100%). The national mean of urinary iodine was 266 micrograms by liter, being it lower in the jungle areas (206 micrograms by liter) and higher in the rest of the coast (302 micrograms by liter), these values are above the level recommended by the World Health Organization in all domains (average higher than 200 micrograms by liter), value that ensures control over the iodine deficiency disorders (IDD). Conclusions. Control of IDD associated with iodized salt consumption is good, and monitoring of the presence of iodine in salt, particularly in the areas with lowest access, should continue.


Asunto(s)
Humanos , Masculino , Femenino , Cloruro de Sodio Dietético , Deficiencia de Yodo , Encuestas Nutricionales , Yodo , Yodo/orina , Estudios Transversales , Estudios Observacionales como Asunto , Perú
18.
Metabolism ; 59(7): 935-42, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20022071

RESUMEN

Oxidative stress damage to biomolecules has been implicated in several diseases including diabetes mellitus. In the present study, we investigated the effect of oxidative stress in whole blood (WB) from diabetic patients (n = 60) on recombinant human insulin. Insulin was incubated with WB obtained from diabetic patients (DP) who had hyperglycemia (>300 mg/dL) or from 41 healthy volunteers (HV). Whole blood of DP, unlike WB of HV, induced higher values of formazan (142%), dityrosines (279%), and carbonyls (58%) in the insulin residues. Interestingly, the insulin modified by WB of DP showed less hypoglycemic activity in rat (30%) in comparison with insulin incubated with WB of HV. The incubation of insulin in WB from DP induces chemical changes in insulin and a decrease in its biological activity, events that might be associated with the high levels of oxidative stress markers found in the plasma of these patients.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Insulina/metabolismo , Estrés Oxidativo/fisiología , Área Bajo la Curva , Biomarcadores , Glucemia/metabolismo , Femenino , Formazáns/metabolismo , Humanos , Hipoglucemiantes/uso terapéutico , Inyecciones Intraperitoneales , Insulina/química , Hierro/sangre , Masculino , Malondialdehído/metabolismo , Persona de Mediana Edad , Oxidación-Reducción , Carbonilación Proteica/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo
19.
Artículo en Inglés | MEDLINE | ID: mdl-19942499

RESUMEN

Quantitative ultrasound (QUS) imaging techniques based on ultrasonic backscatter have been used successfully to diagnose and monitor disease. A method for improving the contrast and axial resolution of QUS parametric images by using the resolution enhancement compression (REC) technique is proposed. Resolution enhancement compression is a coded excitation and pulse compression technique that enhances the -6-dB bandwidth of an ultrasonic imaging system. The objective of this study was to combine REC with QUS (REC-QUS) and evaluate and compare improvements in scatterer diameter estimates obtained using the REC technique to conventional pulsing methods. Simulations and experimental measurements were conducted with a single-element transducer (f/4) having a center frequency of 10 MHz and a -6-dB bandwidth of 80%. Using REC, the -6-dB bandwidth was enhanced to 155%. Images for both simulation and experimental measurements contained a signal-to-noise ratio of 28 dB. In simulations, to monitor the improvements in contrast a software phantom with a cylindrical lesion was evaluated. In experimental measurements, tissue-mimicking phantoms that contained glass spheres with different scatterer diameters were evaluated. Estimates of average scatterer diameter in the simulations and experiments were obtained by comparing the normalized backscattered power spectra to theory over the -6-dB bandwidth for both conventional pulsing and REC. Improvements in REC-QUS over conventional QUS were quantified through estimate bias and standard deviation, contrast-to-noise ratio, and histogram analysis of QUS parametric images. Overall, a 51% increase in contrast and a 60% decrease in the standard deviation of average scatterer diameter estimates were obtained during simulations, while a reduction of 34% to 71% was obtained in the standard deviation of average scatterer diameter for the experimental results.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Señales Asistido por Computador , Ultrasonografía/métodos , Algoritmos , Simulación por Computador , Fantasmas de Imagen
20.
Artículo en Inglés | MEDLINE | ID: mdl-19574144

RESUMEN

A method for improving the contrast resolution of B-mode images is proposed by combining the speckle-reduction technique of frequency compounding (FC) and the coded excitation and pulse-compression technique called resolution enhancement compression (REC). FC suppresses speckle but at the expense of a reduction in axial resolution. Using REC, the axial resolution and bandwidth of the imaging system was doubled. Therefore, by combining REC with FC (REC-FC), the tradeoff between axial resolution and contrast enhancement was extended significantly. Simulations and experimental measurements were conducted with a single-element transducer (f/2.66) having a center frequency of 2.25 MHz and a -3-dB bandwidth of 50%. Simulations and measurements of hyperechoic (+6 dB) tissue-mimicking targets were imaged. Four FC cases were evaluated: full-, half-, third-, and fourth-width of the true impulse response bandwidth. The image quality metrics used to compare REC-FC to conventional pulsing (CP) and CP-FC were contrast-to-noise ratio (CNR), speckle signal-to-noise ratio, histogram pixel intensity, and lesion signal-to-noise ratio. Increases in CNR of 121%, 231%, 302%, and 391% were obtained in experiments when comparing REC-FC for the full-, half-, third-, and fourth-width cases to CP. Furthermore, smaller increases in CNR of 112%, 233%, and 309% were obtained in experiments when comparing CP-FC for the half-, third-, and fourth-width cases to CP. Improved lesion detectability was observed by using REC-FC.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía/métodos , Algoritmos , Simulación por Computador , Fantasmas de Imagen , Reproducibilidad de los Resultados
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