Reduced mastication is a risk factor for Rome IV postprandial distress syndrome in patients investigated with upper endoscopy.

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.

Reduced masticatory function predicts gastroesophageal reflux disease and esophageal dysphagia in patients referred for upper endoscopy: A cross-sectional study.

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.

Cancer Cell Fitness Is Dynamic.

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.

Nuclear morphometric analysis in tissue as an objective tool with potential use to improve melanoma staging.

Alterations in nuclear size and shape are commonly observed in cancers, and its objective evaluation may provide valuable clinical information about the outcome of the disease. Here, we applied the nuclear morphometric analysis in tissues in hematoxylin and eosin-digitized slides of nevi and melanoma, to objectively contribute to the prognostic evaluation of these tumors. To this, we analyzed the nuclear morphometry of 34 melanomas classified according to the TNM stage. Eight cases of melanocytic nevi were used as non-neoplastic tissues to set the non-neoplastic parameters of nuclear morphology. Our samples were set as G1 (control, nevi), G2 (T1T2N0M0), G3 (T3T4N0M0), G4 (T1T2N1M1), and G5 (T3T4N1M1). Image-Pro Plus 6.0 software was used to acquire measurements related to nuclear size (variable: Area) and shape (variables: Aspect, AreaBox, Roundness, and RadiusRatio, which were used to generate the Nuclear Irregularity Index). From these primary variables, a set of secondary variables were generated. All the seven primary and secondary variables related to the nuclear area were different among groups (Pillai's trace P<0.001), whereas Nuclear Irregularity Index, which is the variable related to nuclear shape, did not differ among groups. The secondary variable 'Average Area of Large Nuclei' was able to differ all pairwise comparisons, including thin nonmetastatic from thin metastatic tumors. In conclusion, the objective quantification of nuclear area in hematoxylin and eosin slides may provide objective information about the risk stratification of these tumors and has the potential to be used as an additional method in clinical decision making.

Cytological and genome size data analyzed in a phylogenetic frame: Evolutionary implications concerning Sisyrinchium taxa (Iridaceae: Iridoideae).

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.

Cytological and genome size data analyzed in a phylogenetic frame: Evolutionary implications concerning Sisyrinchium taxa (Iridaceae: Iridoideae)

Abstract 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.

The Impact of Gastric Bypass on Gastroesophageal Reflux Disease in Morbidly Obese Patients.

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.

Corticosteroid receptor genes and childhood neglect influence susceptibility to crack/cocaine addiction and response to detoxification treatment.

The aim of this study was to analyze hypotheses-driven gene-environment and gene-gene interactions in smoked (crack) cocaine addiction by evaluating childhood neglect and polymorphisms in mineralocorticoid and glucocorticoid receptor genes (NR3C2 and NR3C1, respectively). One hundred thirty-nine crack/cocaine-addicted women who completed 3 weeks of follow-up during early abstinence composed our sample. Childhood adversities were assessed using the Childhood Trauma Questionnaire (CTQ), and withdrawal symptoms were assessed using the Cocaine Selective Severity Assessment (CSSA) scale. Conditional logistic regression with counterfactuals and generalized estimating equation modeling were used to test gene-environment and gene-gene interactions. We found an interaction between the rs5522-Val allele and childhood physical neglect, which altered the risk of crack/cocaine addiction (Odds ratio = 4.0, P = 0.001). Moreover, a NR3C2-NR3C1 interaction (P = 0.002) was found modulating the severity of crack/cocaine withdrawal symptoms. In the post hoc analysis, concomitant carriers of the NR3C2 rs5522-Val and NR3C1 rs6198-G alleles showed lower overall severity scores when compared to other genotype groups (P-values ≤ 0.035). This gene-environment interaction is consistent with epidemiological and human experimental findings demonstrating a strong relationship between early life stress and the hypothalamic-pituitary-adrenal (HPA) axis dysregulation in cocaine addiction. Additionally, this study extended in crack/cocaine addiction the findings previously reported for tobacco smoking involving an interaction between NR3C2 and NR3C1 genes.

Is there a role for ADORA2A polymorphisms in levodopa-induced dyskinesia in Parkinson's disease patients?

AIM: Levodopa is first line treatment of Parkinson's disease (PD). However, its use is associated with the presence of motor fluctuations and dyskinesias. In recent years, adenosine A2A receptor (A2AR) is rising as a therapeutic target for PD. The aim of the present study was to investigate whether ADORA2A is associated with levodopa adverse effects. PATIENTS & METHODS: Two hundred and eight PD patients on levodopa therapy were investigated. rs2298383 and rs3761422 at the ADORA2A gene were genotyped by allelic discrimination assays. RESULTS: A trend for association was observed for both polymorphism and diplotypes with dyskinesia. CONCLUSION: The present results should be considered as positive preliminary evidence. Further studies are needed to determine the association between ADORA2A and dyskinesia. Original submitted 3 December 2014; Revision submitted 13 February 2015.

MR and GR functional SNPs may modulate tobacco smoking susceptibility.

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.

Gastric yield pressure and gastric yield volume to assess anti-reflux barrier in a porcine model.

Anti-reflux barrier (ARB) resistance may be useful to test new treatments for gastroesophageal reflux (GER). The ARB has been estimated by increasing gastric yield pressure (GYP) and gastric yield volume (GYV) in animal models but has not been validated. This study aimed to develop an experimental model suitable for assessing the ARB resistance to increasing intragastric pressure and volume and its reproducibility in a seven-day interval. Ten two-month-old female Large-White swine were studied. Intragastric pressure and volume were recorded using a digital system connected to a Foley catheter inserted through gastrostomy into the stomach. GYP and GYV were defined as the gastric pressure and volume able to yield gastric contents into the esophagus detected by esophageal pH. A sudden pH drop below 3 sustained during 5 min was considered diagnostic for gastric yield. Animals were studied again after seven days. On days 0 and 7, there were no significant differences for GYP (mean ± SD = 7.66 ± 3.02 mmHg vs. 7.07 ± 3.54 mmHg, p = .686) and GYV (636.70 ± 216.74 ml vs. 608.30 ± 276.66 ml; p = .299), respectively. Concordance correlation coefficient (ρc) was significant for GYP (ρc = 0.634, 95% CI = 0.141-0.829, p = .006), but not for GYV (ρc = 0.291, 95% CI = -0.118 to 0.774, p = .196). This study demonstrated an experimental model, assessing the ARB resistance. GYP seems to be a more reliable parameter than GYV for assessment of ARB resistance.

IL1B, IL4R, IL12RB1 and TNF gene polymorphisms are associated with Plasmodium vivax malaria in Brazil.

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.

The impact of gastric bypass on gastroesophageal reflux disease in patients with morbid obesity: a prospective study based on the Montreal Consensus.

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.

Prevalence of common α -thalassemia determinants in south Brazil: importance for the diagnosis of microcytic anemia

Alpha thalassemia has not been systematically investigated in Brazil. In this study, 493 unrelated individuals from the southernmost Brazilian state of Rio Grande do Sul were screened for deletional forms of α-thalassemia. One hundred and one individuals had microcytic anemia (MCV < 80 fL) and a normal hemoglobin pattern (Hb A2 < 3.5 percent and Hb F < 1 percent). The subjects were screened for -α3.7,-α4.2,-α20.5, -SEA and -MED deletions but only the -α3.7 allele was detected. The -α3.7 allele frequency in Brazilians of European and African ancestry was 0.02 and 0.12, respectively, whereas in individuals with microcytosis the frequency was 0.20. The prevalence of α-thalassemia was significantly higher in individuals with microcytosis than in healthy individuals (p = 0.001), regardless of their ethnic origin. There were also significant differences in the hematological parameters of individuals with -α3.7/αα, -α3.7/α3.7 and β-thalassemia trait compared to healthy subjects. These data suggest that α-thalassemia is an important cause of microcytosis and mild anemia in Brazilians.

Endoscopic augmentation of the esophagogastric junction with polymethylmethacrylate: durability, safety, and efficacy after 6 months in mini-pigs.

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.

Performance of the Montreal Consensus in the diagnosis of gastroesophageal reflux disease in morbidly obese patients.

BACKGROUND: Gastroesophageal reflux disease (GERD) has been increasingly recognized in patients with morbid obesity. A recent global evidence-based consensus on GERD has been proposed, but its performance in patients with morbid obesity is unknown. The aim of this study was to assess the performance of the Montreal Consensus in the diagnosis of GERD in morbidly obese patients. METHODS: Seventy-five consecutive morbidly obese patients underwent GERD symptoms assessment, upper gastrointestinal endoscopy, and ambulatory esophageal pH monitoring "off PPI". The performance of the Montreal Consensus was determined by comparing two diagnostic algorithms: 1. a gold standard approach in which any GERD symptom and findings from both endoscopy and pH monitoring were taken into account, and 2. the approach with the Montreal Consensus, in which troublesome GERD symptoms and endoscopic findings were considered. RESULTS: GERD was found present in 57 patients by applying the gold standard approach. The Montreal Consensus identified 41 of these patients, whereas the remaining 34 patients were classified as "no GERD". Of these, 16 (47%) showed reflux esophagitis and/or abnormal pH-metry. The Montreal Consensus had an accuracy of 78.7%, sensitivity of 72% (95% CI 59-82%), specificity of 100% (95% CI 82-100%) and negative predictive value of 47% (95% CI 37-57%). CONCLUSIONS: In morbidly obese patients, the approach with the Montreal Consensus has high specificity and suboptimal sensitivity in the diagnosis of GERD. Its intermediate negative predictive value suggests that complementary investigation might be routine in these patients, particularly in those who do not present with troublesome GERD symptoms.

Is ineffective oesophageal motility associated with reflux oesophagitis?

OBJECTIVE: To evaluate the association between ineffective oesophageal motility and reflux oesophagitis controlling for hiatal hernia, hypotensive lower oesophageal sphincter and male sex in patients with gastro-oesophageal reflux disease. METHODS: A total of 387 patients with reflux disease (mean age, 46 years, 42% men) were consecutively selected from a database. All patients underwent upper endoscopy, oesophageal manometry and 24 h oesophageal pH-metry in accordance with a standardized protocol. Reflux disease was confirmed either by endoscopy (oesophagitis grade I-IV according to Savary-Miller) or by pH-metry (increased acid exposure). Hiatal hernia was diagnosed endoscopically, whereas ineffective oesophageal motility and hypotensive lower oesophageal sphincter were characterized during manometry testing. The association between ineffective oesophageal motility and reflux oesophagitis was assessed by logistic regression analysis. RESULTS: A total of 166 patients with oesophagitis (mean age 45 years, 49% men) and 221 without oesophagitis (mean age 46 years, 37% men) were present. Prevalences of ineffective oesophageal motility, hiatal hernia, hypotensive lower oesophageal sphincter and male sex were significantly higher in patients with oesophagitis compared with those without oesophagitis (P<0.05). Ineffective oesophageal motility was independently associated with oesophagitis after multivariate logistic regression analysis (odds ratio=1.68; 95% confidence interval=1.04-2.70). CONCLUSION: Ineffective oesophageal motility is associated with reflux oesophagitis, independently of hiatal hernia, hypotensive lower oesophageal sphincter and male sex.

Brazilian indian/non indian interactions and their effects

A short review was made of the history of the Brazilian population, starting with the Asians who colonized the region 30,000-40,000 years ago, and continuing with evaluations of the European, African, and neo-Asiatic immigration. Social aspects of the contact situation between Brazilian Indians and the surrounding society were briefly considered, as well as quantitative estimates of the amount of Amerindian genes present in neo-Brazilians. Special emphasis, however, was placed in the inverse gene flow (neo-Brazilian genes into Amerindians). In this case, two methods which quantify the degree of such admixture were employed, and the one considered to give better estimates was chosen. Although the correlation obtained between these admixture values and the number of years of more permanent contact with non-Indians yielded a low number (perhaps due to deficiencies in obtaining precise figures concerning years of contact), a clear correlation was found between the admixture estimates obtained in 39 Brazilian Indian tribes or populations and their location in degrees of longitude west. This is probably a reflection of the general neo-Brazilian east-west colonization movement. At present it is difficult to ascertain the degree of biological and cultural homogeneity that will be reached by Brazilian populations in the future. It is hoped, however, that a certain amount of diversity will be maintained, in a climate of mutual respect.

Medidas de associaçäo em estudos epidemiologicos: risco relativo e odds ratio / Measures of association in epidemiological studies: relative risk and odds ratio

Objetivos: Descrever os aspectos essenciais do risco relativo e do odds ratio, incluindo fórmulas para o cálculo de intervalos de confiança. Métodos: Revisäo de diversos livros de epidemiologia, bioestatística e artigos selecionados. Resultados: O risco relativo (RR) é uma medida da força da associaçäo entre um fator de risco e o desfecho em um estudo epidemiológico. E definido como sendo a razäo entre a incidência entre indivíduos expostos e a incidência entre os näo-expostos. E usualmente utilizado em estudos de coorte. O odds ratio é uma estimativa do risco relativo. Possui a mesma interpretaçäo, apesar de ser baseado em uma fórmula diferente. Esta medida é particularmente indicada para estudos de caso-controle. Outras medidas de associaçäo encontradas na literatura epidemiológica e rapidamente definidas neste artigo incluem a razäo de prevalências, o risco atribuível na populaçäo, a reduçäo do risco relativo e o número necessário a tratar. Conclusäo: As medidas de associaçäo baseadas em razöes, como risco relativo e o odds ratio, fornecem dados sobre a força da associaçäo entre o fator em estudo e o desfecho, permitindo que se faça um julgamento sobre uma relaçäo de causalidade. Assim, o risco ralativo e o odds ratio säo medidas de escolha para estudarmos os possíveis determinantes das doenças, sendo freqüentemente utilizadas em estudos de coorte e de caso-controle, respectivamente...