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1.
Int J Food Sci Nutr ; 73(6): 841-849, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35603590

RESUMEN

A randomised clinical trial was conducted on 20 healthy, low-habitual fibre consumers to assess the short-term effects of water intake (2 l/day) on fibre supplementation with wheat bran, pectin, and green banana flour. During the 14-days trial, fibre intake doubled in both fibre (n = 10) and fibre/water (n = 10) interventions (p < 0.001), whereas daily water intake increased from 538 to 1990 ml in the fibre/water group (p < 0.001). Weekly bowel movements increased similarly in both interventions (fibre: 6.8-8.8; fibre/water: 8.6-10; p < 0.01), while faecal weight (71-126 g; p = 0.009) increased in the fibre/water group. This group showed higher counts of faecal Bacteroides and Prevotella, Faecalibacterium prausnitzii, and Bifidobacterium, whereas both interventions decreased the count of Desulfovibrio. Transient abdominal symptoms occurred less frequently in the fibre/water than in the fibre group (3 vs. 9 participants; p = 0.020). In healthy, low-habitual fibre consumers, short-term water intake helps the intestinal adaptation to fibre supplementation.CLINICAL TRIAL REGISTRATION NUMBER: NCT02838849.


Asunto(s)
Fibras de la Dieta , Ingestión de Líquidos , Bifidobacterium , Suplementos Dietéticos , Heces/microbiología , Humanos , Agua
2.
Genet Mol Biol ; 41(1 suppl 1): 288-307, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29505063

RESUMEN

Sisyrinchium is the largest genus of Iridaceae in the Americas and has the greatest amount of cytological data available. This study aimed at investigating how genomes evolved in this genus. Chromosome number, genome size and altitude from species of sect. Viperella were analyzed in a phylogenetic context. Meiotic and pollen analyses were performed to assess reproductive success of natural populations, especially from those polyploid taxa. Character optimizations revealed that the common ancestor of sect. Viperella was probably diploid (2n = 2x =18) with two subsequent polyplodization events. Total DNA content (2C) varied considerably across the phylogeny with larger genomes detected mainly in polyploid species. Altitude also varied across the phylogeny, however no significant relationship was found between DNA content changes and altitude in our data set. All taxa presented regular meiosis and pollen viability (> 87%), except for S. sp. nov. aff. alatum (22.70%), suggesting a recent hybrid origin. Chromosome number is mostly constant within this section and polyploidy is the only source of modification. Although 2C varied considerably among the 20 taxa investigated, the diversity observed cannot be attributed only to polyploidy events because large variations of DNA content were also observed among diploids.

3.
Ann Surg ; 263(1): 110-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25607766

RESUMEN

OBJECTIVE: To assess the impact of Roux-en-Y gastric bypass (GBP) on gastroesophageal reflux disease (GERD) in morbidly obese patients. BACKGROUND: Recently, authors have reported that early results of GBP can control GERD. However, longer follow-ups based on objective parameters for GERD are missing. METHODS: Fifty-three patients [15 men (28%), 39 years old (range, 18-59), body mass index = 46 ± 7.7 kg/m2] were consecutively evaluated for GERD irrespectively of related symptoms, before the operation (E1) and at 6 (E2) and 39 ± 7 months postoperatively (E3). The end points were (1) esophageal syndromes based on the Montreal Consensus and (2) an esophageal acid exposure assessment. RESULTS: Body mass index dropped from 46 ± 7.7 kg/m2 at E1 to 30 ± 5.2 kg/m2 at E3. Typical reflux syndrome displayed a significant decrease from 31 (58%) at E1 to 8 (15%) at E2 and 5 (9%) at E3. Statistically significant differences occurred between E1 and both postoperative evaluations (P < 0.001). Reflux esophagitis was detected in 24 (45%), 17 (32%), and 10 patients (19%) at E1, E2, and E3, respectively (P = 0.002). The incidence of GERD decreased in 34 (64%) and 21 (40%) patients at E1 and E2, respectively, and then in 12 (23%) patients at E3. DeMeester scores reduced from 28.6 (E1) to 9.4 (E2) and 1.2 (E3) (P < 0.001). CONCLUSIONS: For most morbidly obese patients, in addition to causing significant weight loss, GBP reduces GERD symptoms, improves reflux esophagitis, and decreases esophageal acid exposure for longer than 3 years.


Asunto(s)
Derivación Gástrica , Reflujo Gastroesofágico/complicaciones , Obesidad Mórbida/complicaciones , Obesidad Mórbida/cirugía , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
4.
J Psychiatry Neurosci ; 41(6): 405-412, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27327562

RESUMEN

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) symptoms are dimensionally distributed in the population. This study aimed to assess the role of the catechol-O-methyltransferase (COMT) and of the dopamine transporter (DAT1) genes on ADHD symptoms in the general population. METHODS: We investigated 4101 individuals from the 1993 Pelotas Birth Cohort Study using the parent version of the Strengths and Difficulties Questionnaire (SDQ) at ages 11 and 15 years. The SDQ hyperactivity/inattention scores were the main outcomes. RESULTS: Linear regression analyses demonstrated that the increasing number of COMT158Val and DAT1 10R alleles significantly predicted increasing SDQ hyperactivity/inattention scores in boys at both 11 and 15 years of age (ß coefficient = 0.049, t = 2.189, p = 0.029, R2 = 0.012, and ß coefficient = 0.064, t = 2.832, p = 0.005, R2 = 0.008, respectively). The presence of both COMT158Val and DAT1 10R alleles was also associated with full categorical ADHD diagnosis at 18 years of age in boys (χ2 = 4.561, p = 0.033, odds ratio 2.473, 95% confidence interval 1.048-5.838) from this cohort. We did not observe these associations in girls. LIMITATIONS: Our analyses of SDQ hyperactivity/inattention scores were not corrected for SDQ scores of conduct problems because these variables were highly correlated. CONCLUSION: This study demonstrates a role for COMT and DAT1 genes on hyperactivity/inattention symptoms and provides further support for ADHD as the extreme of traits that vary in the population. It also confirms previous evidence for sexual dimorphism on COMT and DAT1 gene expression.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Catecol O-Metiltransferasa/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Predisposición Genética a la Enfermedad , Caracteres Sexuales , Adolescente , Análisis de Varianza , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Niño , Estudios de Cohortes , Femenino , Frecuencia de los Genes , Técnicas de Genotipaje , Humanos , Modelos Lineales , Masculino , Fenotipo , Prevalencia , Escalas de Valoración Psiquiátrica , Encuestas y Cuestionarios
5.
Genet Mol Biol ; 38(3): 324-31, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26500436

RESUMEN

The population of Argentina has already been studied with regard to several genetic markers, but much more data are needed for the appropriate definition of its genetic profile. This study aimed at investigating the admixture patterns and genetic structure in Central Argentina, using biparental markers and comparing the results with those previously obtained by us with mitochondrial DNA (mtDNA) in the same samples. A total of 521 healthy unrelated individuals living in 13 villages of the Córdoba and San Luis provinces were tested. The individuals were genotyped for ten autosomal ancestry informative markers (AIMs). Allele frequencies were compared with those of African, European and Native American populations, chosen to represent parental contributions. The AIM estimates indicated a greater influence of the Native American ancestry as compared to previous studies in the same or other Argentinean regions, but smaller than that observed with the mtDNA tests. These differences can be explained, respectively, by different genetic contributions between rural and urban areas, and asymmetric gene flow occurred in the past. But a most unexpected finding was the marked interpopulation genetic homogeneity found in villages located in diverse geographic environments across a wide territory, suggesting considerable gene flow.

6.
Genet Mol Biol ; 37(4): 611-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25505833

RESUMEN

The Metabolic Syndrome (MetS) is defined as a pattern of metabolic disturbances, which include central obesity, insulin resistance and hyperglycemia, dyslipidemia, and hypertension. Milk has been promoted as a healthy beverage that can improve the management of MetS. Most human adults, however, down-regulate the production of intestinal lactase after weaning. Lactase encoded by the LCT gene is necessary for lactose digestion. The -13910C > T SNP (rs4988235) is responsible for the lactase persistence phenotype in European populations. We herein investigated whether the lactase persistence genotype is also associated with the MetS in subjects from a Brazilian population of European descent. This study consisted of 334 individuals (average age of 41 years) genotyped by PCR-based methods for the -13910C > T SNP. Clinical data were assessed and the genotypes were tested for their independent contribution to the MetS using chi-square tests and multiple logistic regression analysis. Univariate analyses showed that hypertension and MetS prevalence were higher in individuals with the lactase non-persistence genotype than in lactase persistence subjects. Furthermore, lactase persistence was associated with a lower risk for MetS (OR = 0.467; 95% CI 0.264-0.824; p = 0.009). These results suggest that LCT genotypes can be a valuable tool for the management of MetS treatment.

7.
Int J Neuropsychopharmacol ; 16(6): 1251-1258, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23363854

RESUMEN

The requirement for dopaminergic drugs in Parkinson's disease (PD) is highly variable. Visual hallucinations are a frequent and serious complication of chronic levodopa therapy. Polymorphisms in the DAT1 gene might affect the reuptake of dopamine in the synaptic cleft, but the influence of this variability on adverse effects or levodopa equivalent dose on PD patients is still poorly investigated. Therefore, the aim of the present study was to investigate DAT1 gene polymorphisms on levodopa equivalent dose and visual hallucination occurrence in PD patients. Altogether, 196 PD patients in treatment with at least 200 mg levodopa equivalent dose for at least 1 yr were included. These patients were genotyped for the -839 C > T and 3' VNTR DAT1 polymorphisms by PCR-based methodologies. Visual hallucinations occurred in 25.5% of the sample. After controlling for confounders, the dopamine transporter (DAT) -839 C allele was associated with visual hallucinations (prevalence ratio 2.5, 95% confidence intervals 1.13-5.5, p = 0.02). Levodopa equivalent dose was lower in carriers of the nine repeat allele of the DAT 3'UTR VNTR (741.2 ± 355.0 vs. 843.4 ± 445.7), explaining 21% of dose variability (p = 0.01). Our results support an effect of DAT1 polymorphisms in adverse effects of anti-Parkinsonian drugs and in levodopa equivalent dose usage.

8.
J Neural Transm (Vienna) ; 120(10): 1499-505, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23543128

RESUMEN

A number of studies have demonstrated that stress is involved in all aspects of smoking behavior, including initiation, maintenance and relapse. The mineralocorticoid (MR) and glucocorticoid (GR) receptors are expressed in several brain areas and play a key role in negative feedback of the hypothalamic-pituitary-adrenal (HPA) axis. As nicotine increases the activation of the HPA axis, we wondered if functional SNPs (single nucleotide polymorphisms) in MR and GR coding genes (NR3C2 rs5522 and NR3C1 rs6198, respectively) may be involved in smoking susceptibility. The sample included 627 volunteers, of which 514 were never-smokers and 113 lifetime smokers. We report an interaction effect between rs5522 and rs6198 SNPs. The odds ratio (OR) for the presence of the NR3C2 rs5522 Val allele in NR3C1 rs6198 G carriers was 0.18 (P = 0.007), while in rs6198 G noncarriers the OR was 1.83 (P = 0.027). We also found main effects of the NR3C1 rs6198 G allele on number of cigarettes smoked per day (P = 0.027) and in total score of the Fagerström Test for Nicotine Dependence (P = 0.007). These findings are consistent with a possible link between NR3C2 and NR3C1 polymorphisms and smoking behavior and provide a first partial replication for a nominally significant GWAS finding between NR3C2 and tobacco smoking.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética , Fumar/genética , Adulto , Femenino , Genotipo , Humanos , Masculino
9.
Malar J ; 11: 409, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23217179

RESUMEN

BACKGROUND: Malaria is among the most prevalent parasitic diseases worldwide. In Brazil, malaria is concentrated in the northern region, where Plasmodium vivax accounts for 85% disease incidence. The role of genetic factors in host immune system conferring resistance/susceptibility against P. vivax infections is still poorly understood. METHODS: The present study investigates the influence of polymorphisms in 18 genes related to the immune system in patients with malaria caused by P. vivax. A total of 263 healthy individuals (control group) and 216 individuals infected by P. vivax (malaria group) were genotyped for 33 single nucleotide polymorphisms (SNPs) in IL1B, IL2, IL4, IL4R, IL6, IL8, IL10, IL12A, IL12B, IL12RB1, SP110, TNF, TNFRSF1A, IFNG, IFNGR1, VDR, PTPN22 and P2X7 genes. All subjects were genotyped with 48 ancestry informative insertion-deletion polymorphisms to determine the proportion of African, European and Amerindian ancestry. Only 13 SNPs in 10 genes with differences lower than 20% between cases and controls in a Poisson Regression model with age as covariate were further investigated with a structured population association test. RESULTS: The IL1B gene -5839C > T and IL4R 1902A > G polymorphisms and IL12RB1 -1094A/-641C and TNF -1031 T/-863A/-857 T/-308 G/-238 G haplotypes were associated with malaria susceptibility after population structure correction (p = 0.04, p = 0.02, p = 0.01 and p = 0.01, respectively). CONCLUSION: Plasmodium vivax malaria pathophysiology is still poorly understood. The present findings reinforce and increase our understanding about the role of the immune system in malaria susceptibility.


Asunto(s)
Interleucina-1beta/genética , Subunidad alfa del Receptor de Interleucina-4/genética , Malaria Vivax/genética , Malaria Vivax/inmunología , Receptores de Interleucina-12/genética , Factor de Necrosis Tumoral alfa/genética , Adolescente , Adulto , Brasil/epidemiología , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Interacciones Huésped-Parásitos/genética , Interacciones Huésped-Parásitos/inmunología , Humanos , Malaria Vivax/epidemiología , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Adulto Joven
10.
Am J Phys Anthropol ; 147(3): 427-32, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22271590

RESUMEN

Lactase persistence (LP) is the phenotypic trait in which lactase secretion is maintained during adulthood. LP is due to mutations in the LCT enhancer region, located 14-kb upstream of the gene. In Europeans, the -13910*T allele is associated with LP. In Africans this allele is rare while other mutations in this same region were related to LP. The LCT is highly polymorphic in human populations, but so far Brazilian Amerindians had not been investigated for these polymorphisms or for the presence of LP mutations. We describe the genetic diversity of the LCT region and the presence of LP enhancer mutations in four native Brazilian populations (Guarani-Kaiowá, Guarani-Ñandeva, Kaingang, and Xavante). Twelve polymorphisms were genotyped by PCR-based methods. The -13910*T allele varied from 0.5% in the Xavante to 7.6% in the Guarani-Ñandeva. These frequencies probably derive from European sources and they correlate with non-native admixture proportions previously estimated for these groups. But since admixture is virtually absent in the Xavante, we suggest that the presence of the LP allele could have been determined by a de novo mutation. No other mutations in the -14 kb enhancer region were found. The LCT was highly polymorphic in the present sample showing 15 haplotypes with a heterogeneous distribution among the four Amerindian populations. This diversity could be due to drift, as indicated by the neutrality test performed.


Asunto(s)
Elementos de Facilitación Genéticos , Indígenas Sudamericanos/genética , Lactasa/genética , Polimorfismo de Nucleótido Simple , Brasil , Frecuencia de los Genes , Variación Genética , Genotipo , Humanos
11.
Clin Res Hepatol Gastroenterol ; 46(10): 102032, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36244614

RESUMEN

BACKGROUND AND AIMS: Reduced mastication could force the stomach to do extra work on crushing food and contribute to dyspeptic symptoms. This study aimed to assess the relationship between mastication and dyspepsia. METHODS: This cross-sectional study involved 209 consecutive patients referred for elective upper endoscopy. Before endoscopy, an expert dentist performed an oral examination and scored chewing function in three levels (normal, regular, and reduced), and applied questionnaires for assessment of dyspepsia (Rome IV), xerostomia, and mastication (normal, regular, and reduced). A reduced masticatory function was defined when an oral examination or mastication questionnaire rated the chewing as poor. Associations between mastication, confounders, and dyspepsia were estimated by prevalence ratio [PR (95% Confidence Interval)] using Poisson regression. RESULTS: Thirty-four patients showed relevant organic conditions in the upper gastrointestinal tract (moderate to severe reflux oesophagitis, peptic ulcer, neoplasia, and surgical modification) and were excluded. Among 175 patients with non-organic diseases (aging 51.3 ± 15.7 years; 61.7% women), 50 (28.6%) had reduced mastication, and 125 (71.4%) had normal/regular mastication. After adjusting for age and xerostomia, reduced mastication was associated with postprandial distress syndrome [PR = 1.93 (95%CI 1.27 - 2.91)] but not with epigastric pain syndrome [PR = 1.09 (95%CI 0.75 - 1.60)]. CONCLUSIONS: In patients referred for upper digestive endoscopy, reduced mastication was associated with postprandial distress syndrome but not with epigastric pain syndrome. An interdisciplinary approach with dentists and physicians might benefit dyspeptic patients with postprandial distress syndrome.


Asunto(s)
Dispepsia , Gastropatías , Xerostomía , Humanos , Femenino , Masculino , Dispepsia/etiología , Masticación , Estudios Transversales , Ciudad de Roma , Dolor Abdominal/etiología , Factores de Riesgo , Síndrome , Xerostomía/complicaciones
12.
Dig Liver Dis ; 54(3): 331-335, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34645595

RESUMEN

BACKGROUND: The role of mastication on gastroesophageal reflux disease (GERD) is unknown. AIMS: To assess whether reduced masticatory function predicts GERD and esophageal dysphagia in patients investigated with upper endoscopy. METHODS: In this cross-sectional study, 179 adult patients referred for elective upper gastrointestinal endoscopy agreed to participate. Before endoscopy, an expert dentist performed an oral examination and scored chewing function in three levels (normal, regular, and reduced). Patients replied questionnaires for assessment of GERD (heartburn, regurgitation, and dysphagia), xerostomia, and mastication (normal, regular, and reduced). Poor chewing was defined when either oral examination or mastication questionnaire rated the chewing function as reduced. Associations of mastication with GERD and dysphagia were estimated using Poisson regression. RESULTS: Eleven patients were excluded. Among 168 analyzed (aging 49.8 ± 15.5 years; 58.9% women), 46 had reduced masticatory function (27.4%), and 122 had regular/normal mastication (72.6%). Reduced mastication was associated with GERD [PR = 1.38 (95%CI 1.12 - 1.70)], adjusting for age, and with esophageal dysphagia [PR = 2.03 (95%CI 1.02 - 4.04)], adjusting for age and xerostomia. CONCLUSIONS: In outpatients referred for upper gastrointestinal endoscopy, reduced masticatory function defined by an expert dentist may be a risk factor for GERD and esophageal dysphagia.


Asunto(s)
Trastornos de Deglución/diagnóstico , Diagnóstico Bucal , Endoscopía Gastrointestinal , Reflujo Gastroesofágico/diagnóstico , Masticación , Adulto , Estudios Transversales , Trastornos de Deglución/fisiopatología , Femenino , Reflujo Gastroesofágico/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Encuestas y Cuestionarios
13.
Dig Dis Sci ; 56(5): 1420-6, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20972851

RESUMEN

BACKGROUND: Obesity is a risk factor for GERD and a potential modulator of esophageal motility. AIM: To assess whether obese patients differ from non-obese patients in terms of esophageal motility and reflux. METHODS: Patients (n = 332) were categorized in GERD and controls after clinical assessment, esophageal manometry, and pH monitoring. Non-obese (BMI 16-29.9) and obese (BMI 30-68) were compared in regard of distal esophageal amplitude (DEA), LES pressure (LESP), manometric diagnosis, and esophageal acid exposure (EAE). RESULTS: Obese showed higher DEA in both controls (122 ± 53 vs. 97 ± 36 mmHg, p = 0.041) and GERD patients (109 ± 38 vs. 94 ± 46 mmHg, p < 0.001), higher LESP in GERD patients (20.5 ± 10.6 vs. 18.2 ± 10.6 mmHg, p = 0.049), higher frequency of nutcracker esophagus in controls (30 vs. 0%, p = 0.001), lower frequency of ineffective motility in GERD patients (6 vs. 20%, p = 0.001), and higher EAE in both controls [total EAE: 1.6% (0.7-5.1) vs. 0.9% (0.2-2.4), p = 0.027] and GERD patients [upright EAE: 6.5% (3.8-11.1) vs. 5.2% (1.5-10.6), p = 0.048]. Multiple linear regression showed that BMI was associated either with EAE (p < 0.001), DEA (p = 0.006), or LESP (in men, p = 0.007). CONCLUSIONS: Obese patients differed from non-obese in terms of esophageal motility and reflux, regardless of the presence of GERD. Obese patients showed stronger peristalsis and increased acid exposure in the esophagus.


Asunto(s)
Esófago/patología , Ácido Gástrico/fisiología , Reflujo Gastroesofágico/diagnóstico , Obesidad/complicaciones , Peristaltismo/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Monitorización del pH Esofágico , Esófago/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
14.
Am J Phys Anthropol ; 145(3): 371-81, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21520008

RESUMEN

Information on one Ecuadorian and three Peruvian Amerindian populations for 11 autosomal short tandem repeat (STR) loci is presented and incorporated in analyses that includes 26 other Native groups spread all over South America. Although in comparison with other studies we used a reduced number of markers, the number of populations included in our analyses is currently unmatched by any genome-wide dataset. The genetic polymorphisms indicate a clear division of the populations into three broad geographical areas: Andes, Amazonia, and the Southeast, which includes the Chaco and southern Brazil. The data also show good agreement with proposed hypotheses of splitting and dispersion of major language groups over the last 3,000 years. Therefore, relevant aspects of Native American history can be traced using as few as 11 STR autosomal markers coupled with a broad geographic distribution of sampled populations.


Asunto(s)
Evolución Molecular , Indígenas Sudamericanos/genética , Lenguaje , Repeticiones de Microsatélite/genética , Análisis de Varianza , Análisis por Conglomerados , Frecuencia de los Genes , Genética de Población , Geografía , Humanos , Masculino , Modelos Genéticos , América del Sur
15.
Cancer Res ; 81(4): 1040-1051, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33355182

RESUMEN

Several phenotypes that impact the capacity of cancer cells to survive and proliferate are dynamic. Here we used the number of cells in colonies as an assessment of fitness and devised a novel method called Dynamic Fitness Analysis (DynaFit) to measure the dynamics in fitness over the course of colony formation. DynaFit is based on the variance in growth rate of a population of founder cells compared with the variance in growth rate of colonies with different sizes. DynaFit revealed that cell fitness in cancer cell lines, primary cancer cells, and fibroblasts under unhindered growth conditions is dynamic. Key cellular mechanisms such as ERK signaling and cell-cycle synchronization differed significantly among cells in colonies after 2 to 4 generations and became indistinguishable from randomly sampled cells regarding these features. In the presence of cytotoxic agents, colonies reduced their variance in growth rate when compared with their founder cell, indicating a dynamic nature in the capacity to survive and proliferate in the presence of a drug. This finding was supported by measurable differences in DNA damage and induction of senescence among cells of colonies. The presence of epigenetic modulators during the formation of colonies stabilized their fitness for at least four generations. Collectively, these results support the understanding that cancer cell fitness is dynamic and its modulation is a fundamental aspect to be considered in comprehending cancer cell biology and its response to therapeutic interventions. SIGNIFICANCE: Cancer cell fitness is dynamic over the course of the formation of colonies. This dynamic behavior is mediated by asymmetric mitosis, ERK activity, cell-cycle duration, and DNA repair capacity in the absence or presence of a drug.


Asunto(s)
Proliferación Celular/fisiología , Aptitud Genética/fisiología , Neoplasias/patología , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Células Clonales/patología , Células Clonales/fisiología , Daño del ADN/efectos de los fármacos , Daño del ADN/fisiología , Aptitud Genética/efectos de los fármacos , Humanos , Células MCF-7 , Mitosis/efectos de los fármacos , Mitosis/fisiología , Temozolomida/farmacología , Ensayo de Tumor de Célula Madre
16.
Ann Surg ; 251(2): 244-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20010088

RESUMEN

OBJECTIVES: To assess the impact of gastric bypass (GBP) on gastroesophageal reflux disease (GERD) based on Montreal Consensus. METHODS: In this study, 86 patients (25 men; aging 38 +/- 12 years; body mass index 45 [35-68 kg/m2]) were investigated for GERD before GBP and 6 months later. Esophageal and extraesophageal syndromes were assessed based on Montreal Consensus. Esophageal acid exposure and gastric pouch acidity were also evaluated. RESULTS: Overall prevalence of GERD was 64% before GBP and 33% after GBP (P < 0.0001). Typical reflux syndrome (TRS) was present in 47 patients (55%) preoperatively and disappeared in 39 of them (79%) post-GBP. Out of 39 patients with no symptoms, 4 (10%) developed TRS postoperatively (P < 0.0001). The chief TRS complaint changed from heartburn pre-GBP (96%) to regurgitation post-GBP (64%). Esophageal mucosa improved in 27, was unchanged in 51, and worsened in 8 patients (P = 0.001) in regard of esophagitis. Extraesophageal syndromes were present in 16 patients preoperatively and in none but one post-GBP (P = 0.0003). GERD-related well being and use of proton pump inhibitors were both improved after GBP. Total acid exposure decreased from a median (interquartile range, 25%-75%) of 5.1% (range, 2-8.2) to 1.1% (range, 0.2-4.8), P = 0.0002. Most patients (86%) showed and acid gastric pouch in fasting conditions post-GBP. CONCLUSIONS: GBP ameliorated GERD syndromes in most patients 6 months after the procedure, resulting in quality of life improvement and less proton pump inhibitors usage. Whether regurgitation post-GBP corresponds to reflux disease or bad eating behavior deserves further studies.


Asunto(s)
Derivación Gástrica , Reflujo Gastroesofágico/complicaciones , Obesidad Mórbida/complicaciones , Obesidad Mórbida/cirugía , Adulto , Femenino , Humanos , Masculino , Estudios Prospectivos
17.
Am J Phys Anthropol ; 143(3): 458-64, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20623607

RESUMEN

The DRD4 variable number of tandem repeats (VNTR) allele distribution of 172 Guarani (Kaiowá and Ñandeva subgroups) and Kaingang Brazilian Amerindians is reported. These results are integrated with those previously obtained for this ethnic group. Allele frequencies for the three populations are within the interval observed for 15 other Native American populations and show intermediate values between those observed in Amazonia and Patagonia. Significant differences in allele distribution between recent past hunter-gatherer and agriculturalist populations are observed, with an increase of the 7R allele among hunter-gatherers (P < 0.001). Analysis of molecular variance (AMOVA) and pairwise F(ST) data suggest three distinct sectors for the genetic landscape of Native South America: Andes, Center/Southeast region, and Amazonia. Common traits among hunter-gatherers such as novelty-seeking temperament, hyperactivity, and impulsivity could have been important and advantageous in new environments during America's prehistoric colonization.


Asunto(s)
Alelos , Indígenas Sudamericanos/genética , Receptores de Dopamina D4/genética , Análisis de Varianza , Evolución Molecular , Conducta Exploratoria , Frecuencia de los Genes , Haplotipos , Humanos , Repeticiones de Minisatélite , Polimorfismo de Nucleótido Simple , Estadísticas no Paramétricas
18.
Am J Med Sci ; 360(4): 378-382, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32620270

RESUMEN

BACKGROUND: The effect of abdominal palpation on bowel sounds is controversial. The authors developed an auscultation apparatus to count bowel sounds and determined whether abdominal palpation modifies the number of bowel sounds in healthy volunteers and gastrointestinal outpatients. METHODS: Four medical students developed an auscultation apparatus by attaching a Littmann stethoscope to an electret condenser microphone. The students examined 20 healthy volunteers and 20 gastrointestinal outpatients between March and June 2018. Abdominal auscultation lasting 4 minutes (1-minute each quadrant) was performed before and after abdominal palpation with registration of sound tracings. The software Audacity was used to count the bowel sounds. The effect of palpation on bowel sounds was analyzed using Generalized Estimating Equations. RESULTS: The volunteers were predominantly young (mean ± SD, 21 ± 2 years) and men (70%), whereas the outpatients were older (60 ± 11 years) and women (80%). The apparatus was able to generate sound tracings with good quality from all participants. In the comparison before/after palpation, the number of bowel sounds did not differ either in volunteers (mean ± SD, 12.6 ± 4.7 and 11.6 ± 3.5; P = 0.482) or in patients (15.6 ± 7.5 and 15.8 ± 7.9; P = 0.714). In the analysis of all participants, the difference before-after palpation was not statistically significant (mean ± SD, 14.1 ± 6.3 and 13.7 ± 6.4, respectively; P = 0.550; mean difference = 0.4; 95% CI -1.2 to 2.0) and did not depend on the group studied. CONCLUSIONS: Using an apparatus devised by medical students, the authors found that abdominal palpation did not modify the number of bowel sounds in healthy volunteers and gastrointestinal outpatients.


Asunto(s)
Auscultación/métodos , Enfermedades Gastrointestinales/diagnóstico , Motilidad Gastrointestinal/fisiología , Tracto Gastrointestinal/fisiopatología , Palpación/métodos , Adulto , Estudios Transversales , Femenino , Enfermedades Gastrointestinales/fisiopatología , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Sonido , Adulto Joven
19.
J Hered ; 100(3): 309-21, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19060234

RESUMEN

The sigmodontine South American rodent genus Oligoryzomys was first described as a subgenus of the genus Oryzomys to group together species distinguished by morphological measurements. To describe the dispersion patterns of this genus in South America, in this study, a total of 100 sequences were analyzed and compared with sequences of 9 Oligoryzomys species from GenBank. The sequences comprised 90 mitochondrial cytochrome b genes and 10 nuclear interphotoreceptor retinoid-binding protein genes, from 75 individuals of 7 species from 27 localities. Topologies of different phylogenetic trees revealed Oligoryzomys as a monophyletic genus containing 2 main species groups, one designated as the "Amazon-Cerrado" assemblage and the second as the "Pampa-Andean" clade. The north-to-south geographic pattern observed supports the hypothesis that the genus started from the northern Andes, occupied the Amazon and the Cerrado, and later inhabited the more southern regions of South America.


Asunto(s)
Filogenia , Sigmodontinae/genética , Animales , Citocromos b/genética , ADN Mitocondrial , Evolución Molecular , Genética de Población , Geografía , Sigmodontinae/clasificación , Especificidad de la Especie
20.
Surg Endosc ; 23(11): 2430-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19252945

RESUMEN

BACKGROUND AND AIMS: Endoscopic augmentation of the esophagogastric junction (EGJ) with polymethylmethacrylate (PMMA) has been reported in an experimental short-term study. We assessed whether endoscopic augmentation of the EGJ with PMMA is durable, safe, and efficacious after 6 months in mini-pigs. METHODS: Ten mini-pigs were studied under anesthesia. After a pilot study in two animals, eight mini-pigs underwent lower esophageal sphincter (LES) manometry and gastrostomy with measurement of gastric yield volume (GYV) and gastric yield pressure (GYP). Endoscopic implantation of PMMA was performed aiming for the submucosa of the EGJ. Six months later, LES manometry and GYV and GYP measurements were repeated and animals were sacrificed, followed by microscopic analyses of the EGJ. RESULTS: Out of 32 implants (four per animal), 29 (91%) were identified as submucosal nodules postmortem. PMMA deposits were found at microscopic analysis in all animals and located as follows [mean (range)]: submucosa 61.5% (37.5-91%), muscularis propria 21.5% (0-58%), mucosa 11% (0-25%), and subserosa 6% (0-17%). Neither esophageal perforation nor death was observed. A significant increase in GYV (1,404 versus 905 ml; p = 0.02) and a borderline increase in GYP (8.1 versus 6.5 mmHg; p = 0.057) were detected 6 months later. CONCLUSIONS: Endoscopic augmentation of the esophagogastric junction with PMMA was durable and had no complications after 6 months. However, the occurrence of implants in the subserosa requires technical refinement before use in clinical trials.


Asunto(s)
Endoscopía Gastrointestinal/métodos , Unión Esofagogástrica/cirugía , Reflujo Gastroesofágico/cirugía , Procedimientos de Cirugía Plástica/métodos , Polimetil Metacrilato/farmacología , Animales , Modelos Animales de Enfermedad , Esofagoscopía/métodos , Estudios de Seguimiento , Gastroscopía/métodos , Manometría , Proyectos Piloto , Falla de Prótesis , Implantación de Prótesis , Porcinos , Porcinos Enanos , Resistencia a la Tracción , Resultado del Tratamiento
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