Association of Physical Activity and Sedentary Behavior with Colorectal Cancer Risk in Moroccan Adults: A Large-Scale,Population-Based Case–Control Study

Background:Physical activity has been associated with a lower risk of colorectal cancer in studies mainly conducted in high-income countries, while sedentary behavior has been suggested to increase CRC risk. In this study, we aimed to investigate the role of physical activity and sedentary behavior on CRC risk in the Moroccan population. Methods:A case-control study was conducted involving 1516 case-control pairs, matched on age, sex and center in five university hospital centers. A structured questionnaire was used to collect information on socio-demographics, lifestyle habits, family history of CRC, and non-steroidal anti-inflammatory drug (NSAID) use. Information on physical activity and sedentary behavior were collected by the Global Physical Activity Questionnaire (GPAQ). For each activity (work, household, and recreational activities), a metabolic equivalent (MET) was calculated using GPAQ recommendations. Conditional logistic regression models were used to assess the association between physical activity, sedentary behavior and the risk of overall CRC, colon cancer, and rectal cancer taking into account other CRC risk factors. Results:High level of physical activity was associated with lower risk of rectal cancer, colon cancer, and overall CRC, the adjusted odds ratios (ORa) for the highest versus the lowest level of activity were 0.67 (95% CI: 0.54-0.82), 0.77 (95% CI: 0.62-0.96), and 0.72 (95% CI: 0.62-0.83), respectively. In contrast, sedentary behavior was positively associated with rectal cancer risk (ORa=1.19, 95% CI: 1.01-1.40), but was unrelated to colon cancer risk (ORa=1.02, 95% CI: 0.87-1.20). Conclusion:We found an inverse association between physical activity and CRC risk in the Moroccan population, and a positive association between sedentary behavior and rectal cancer risk. Considering that one-third of the total population studied had a sedentary lifestyle, these results may be used to improve strategies of public health suitable for Moroccan population. Key Words: Physical activity, sedentary behaviour, colorectal cancer risk, Morocco     

Hailey‐Hailey disease in Tunisia

Background Most of the published reports on Hailey‐Hailey disease (HHD) come from European and Asian countries. We report here the clinical and genetic investigation of 20 patients affected with HHD in Tunisia. Methods Affected individuals from three large teaching hospitals in Tunis were recruited for the study over a 25‐year period. Nine patients were identified through the active files and examined together with their family members that were visited in their respective regions. We have clinically examined in total 65 individuals and then identified 11 new cases. Patients were included on the basis of evocative skin lesions, biopsy proven HHD and negative immunofluorescence. Investigations to rule out fungal, bacterial and viral infections were done according to clinical symptoms. Results Twenty patients (12 males and 8 females) from 8 families were included in the present study with more than 55% that were undiagnosed before this investigation. Four patients had mild disease, eight had moderate disease and another eight had severe disease, among whom seven were females. Parental consanguinity was found in 7 cases out of 20 cases (35%). The neck region was first affected in half (4/8) of the male patients. Groins were first affected in 42% (5/12) of the female patients. Depression complicated the course of the disease in two female patients with severe HHD. We report an original association of supernumerary nipples with HHD in two sisters from the north of Tunisia. In 10 patients, the disease has become less troublesome with aging. Conclusion HHD is underestimated. Physicians must be aware of this disease in case of resistant intertriginous dermatosis especially with a positive family history as nine out of 20 patients were misdiagnosed.     

Implication of Xenobiotic Metabolizing Enzyme gene (CYP2E1, CYP2C19, CYP2D6, mEH and NAT2) Polymorphisms in Breast Carcinoma

Background  

Xenobiotic Metabolizing Enzymes (XMEs) contribute to the detoxification of numerous cancer therapy-induced products. This study investigated the susceptibility and prognostic implications of the CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 gene polymorphisms in breast carcinoma patients.     

Ratio Between Positive Lymph Nodes and Total Excised Axillary Lymph Nodes as an Independent Prognostic Factor for Overall Survival in Patients with Nonmetastatic Lymph Node-Positive Breast Cancer

Background

The status of the axillary lymph nodes in nonmetastatic lymph node-positive breast cancer (BC) patients remains the single most important determinant of overall survival (OS). Although the absolute number of nodes involved with cancer is important for prognosis, the role of the total number of excised nodes has received less emphasis. Thus, several studies have focused on the utility of the axillary lymph node ratio (ALNR) as an independent prognostic indicator of OS. However, most studies suffered from shortcomings, such as including patients who received neoadjuvant therapy or failing to consider the use of adjuvant therapy and tumor receptor status in their analysis.

Methods

We conducted a single-center retrospective review of 669 patients with nonmetastatic lymph node-positive BC. Data collected included patient demographics; breast cancer risk factors; tumor size, histopathological, receptor, and lymph node status; and treatment modalities used. Patients were subdivided into four groups according to ALNR value (<.25, .25–.49, .50–.74, .75–1.00). Study parameters were compared at the univariate and multivariate levels for their effect on OS.

Results

On univariate analysis, both the absolute number of positive lymph nodes and the ALNR were significant predictors of OS. On multivariate analysis, only the ALNR remained an independent predictor of OS, with a 2.5-fold increased risk of dying at an ALNR of ≥.25.

Conclusions

Our study demonstrates that ALNR is a stronger factor in predicting OS than the absolute number of positive axillary lymph nodes.     

Diagnostic accuracy of thoracic paraspinal electromyography in amyotrophic lateral sclerosis.

The goal of this study was to estimate the accuracy of thoracic paraspinal (T-PSP) electromyography (EMG), performed at the time of initial evaluation, for the subsequent clinical diagnosis of amyotrophic lateral sclerosis (ALS). Medical records from a consecutive series of patients referred for suspected ALS were abstracted. Those in whom T-PSP EMG was not performed or for whom follow-up was not available were excluded. The study population included 64 patients. T-PSP EMG was abnormal in 28 (44%) study patients, 26 (93%) of whom were subsequently diagnosed with ALS. T-PSP EMG showed neither fibrillation potentials nor positive sharp waves in 36 (56%) patients, 9 (25%) of whom later developed ALS. The sensitivity of T-PSP for the diagnosis of ALS was 0.74 and the specificity was 0.93. The likelihood ratio positive was 10.5 and the likelihood ratio negative was 0.28. These results suggest that T-PSP EMG is very useful for "ruling in" the diagnosis of ALS, but less useful as a screening test for "ruling out" the diagnosis. Because T-PSP EMG is used clinically in an effort to confirm the diagnosis (and not as a screening test), these results suggest that T-PSP EMG is an extremely useful adjunct for the diagnosis of ALS.     

Elaboration of PLLA-based superparamagnetic nanoparticles: characterization, magnetic behaviour study and in vitro relaxivity evaluation

Oleic acid-coated magnetite has been encapsulated in biocompatible magnetic nanoparticles (MNP) by a simple emulsion evaporation method. The different parameters influencing the particles size were studied. Between these parameters, the stirring speed and the polymer concentration were found to influence positively or negatively, respectively, the MNP size which varied between 320 and 1500nm. The magnetite encapsulation efficacy was about than 90% yielding a high magnetite loading of up to 30% (w/w). X-ray diffraction showed that magnetite crystalline pattern was not modified after emulsification and solvent evaporation. The X-ray photoelectron spectroscopy (XPS) results indicated the presence of less than 0.1% of iron atoms at the nanoparticles surface. Vibration simple magnetometer (VSM) showed a superparamagnetic behaviour of the MNP and a saturation magnetization increasing with the increased magnetite amount used in formulation. Moreover, T(1) and T(2) relaxivities of MNP (4.7T, 20 degrees C) were 1.7+/-0.1 and 228.3+/-13.1s(-1)mM(-1), respectively, rendering them in the same category of known negative contrast agents which shorten the T(2) relaxation time. Therefore, by using an appropriate anticancer drug in their formulation, these magnetic nanoparticles can present a promising mean for simultaneous tumor imaging, drug delivery and real time monitoring of therapeutic effect.     

Bradycardia and slowing of the atrioventricular conduction in mice lacking CaV3.1/alpha1G T-type calcium channels

The generation of the mammalian heartbeat is a complex and vital function requiring multiple and coordinated ionic channel activities. The functional role of low-voltage activated (LVA) T-type calcium channels in the pacemaker activity of the sinoatrial node (SAN) is, to date, unresolved. Here we show that disruption of the gene coding for CaV3.1/alpha1G T-type calcium channels (cacna1g) abolishes T-type calcium current (I(Ca,T)) in isolated cells from the SAN and the atrioventricular node without affecting the L-type Ca2+ current (I(Ca,L)). By using telemetric electrocardiograms on unrestrained mice and intracardiac recordings, we find that cacna1g inactivation causes bradycardia and delays atrioventricular conduction without affecting the excitability of the right atrium. Consistently, no I(Ca,T) was detected in right atrium myocytes in both wild-type and CaV3.1(-/-) mice. Furthermore, inactivation of cacna1g significantly slowed the intrinsic in vivo heart rate, prolonged the SAN recovery time, and slowed pacemaker activity of individual SAN cells through a reduction of the slope of the diastolic depolarization. Our results demonstrate that CaV3.1/T-type Ca2+ channels contribute to SAN pacemaker activity and atrioventricular conduction.