ABSTRACT
BACKGROUND: The 6-min walking test (6MWT) is one of the most commonly used tests to assess exercise capacity during chronic obstructive pulmonary disease (COPD). However, it is a relatively time-consuming test. Many authors assessed the usefulness of simpler methods, as the sit-to-stand test (STST), to estimate exercise capacity. PURPOSE: To demonstrate the feasibility of STST, in comparison to 6MWT, for the evaluation of functional status in Tunisian COPD patients and evaluate its correlation to the severity of the disease. METHODS: We studied patients with COPD (Global Initiative for Chronic Obstructive Lung Disease A-D). All patients had plethysmography and manual quadriceps femoris muscle strength evaluation. Each patient completed a 6MWT and a STST. During the tests, dyspnea severity (Borg scale), heart rate, pulsed oxygen saturation, and blood pressure were measured. RESULTS: In 49 patients with stable COPD (mean age 67.06 ± 8.4 years, mean forced expiratory volume in the first second 46.25% ± 19.64%), 6MWT and STST were correlated with each other (r = 0.47, P = 0.001). During 6MWT and STST, the rise in heart rate, systolic blood pressure, and severity of dyspnea were statistically significant compared to baseline (P < 0.05). However, cardiorespiratory stress was lower after STST than after 6MWT (P < 0.05). A statistically significant positive correlation was noted between the 6MWT distance and forced vital capacity (r = 0.357, P < 0.05). The 6MWT was negatively correlated with dyspnea severity at baseline (r = -0.289, P < 0.05) and with BODE index (r = -0.672, P < 0.01). STST was correlated only with age (r = 0.377, P < 0.01). No correlation was found between both tests and quadriceps femoris strength. CONCLUSION: As like as 6MWT, STST can determine functional status during COPD. In addition, it is less time consuming and produces less hemodynamical stress compared to 6MWT. STST can be used as an alternative for 6MWT in patients with COPD.
ABSTRACT
INTRODUCTION: MDM2 was originally identified as an oncoprotein that binds to p53 and inhibits p53-mediated transactivation. Scientists have described functional single-nucleotide polymorphisms (SNP) in the MDM2 gene. They showed that the genotype of SNP 309 induces an increase in the level of MDM2 protein, which causes attenuation of the p53 pathway. In this study, we sought to investigate whether this polymorphism was related to risk of colorectal cancer and whether there were relationships between SNP 309 and protein expression or clinicopathological variables in Tunisian patients. MATERIALS AND METHODS: To investigate the effect of this polymorphism in colorectal cancer pathogenesis, we genotyped 167 patients and 167 blood donors. Immunohistochemistry was performed on normal mucosa and tumor. RESULTS: The rates of MDM2 genotypes were 6.6% for wild-type (T/T) and 93.4% for the SNP 309 polymorphic genotype (T/G and G/G) in patients and 38.3 and 61.7% in controls, respectively. There were significant differences in the frequencies of genotypes between patients and controls (P<0.01). We did not find any relationship between genotypes and clinicopathological features of patients, except in the case of the nonmucinous histological subtype (P=0.001). Moreover, we found that patients with the wild-type genotype (T/T) had significantly more favorable clinical outcome than did patients with the SNP 309 genotype (T/G, G/G) (P=0.005). In addition, we found an association between positive expression of p53 and polymorphic genotypes of MDM2 (T/G, G/G) (P=0.037). There was a significant association between tumoral immunostaning and MDM2 polymorphism (P=0.01). CONCLUSION: Our results suggest that the MDM2 polymorphism is significantly associated with colorectal cancer risk and may provide useful prognostic information for Tunisian patients with colorectal cancer.
