Exercise training modalities and strategies to improve exercise performance in patients with respiratory disease

Pulmonary rehabilitation is an evidence-based, multidisciplinary, comprehensive intervention for patients with chronic respiratory diseases who are symptomatic and whose daily living activities are often restricted. Pulmonary rehabilitation programs are designed to improve the physical and emotional condition of people with chronic respiratory disease and to promote long-term adherence to health-enhancing behavior. Exercise training is at the core of pulmonary rehabilitation (PR) programs. The benefits of exercise training include decreased dyspnea, improved health-related quality of life, fewer days of hospitalization, and decreased health-care utilization. To gain PR benefits, patients should be able to complete an exercise training program, preferably with high intensity exercise, and it is likely that these benefits will translate into a change from a pattern of a sedentary lifestyle to a physically active lifestyle. Chronic respiratory patients, namely COPD patients, have a low exercise tolerance due to multiple factors, such as dynamic hyperinflation and peripheral muscle dysfunction. In this article, the authors describe a variety of modalities and strategies to overcome exercise limitations and improve the effects of exercise training.

Protein purification by aminosquarylium cyanine dye-affinity chromatography

The most selective purification method for proteins and other biomolecules is affinity chromatography. This method is based on the unique biological-based specificity of the biomolecule-ligand interaction and commonly uses biological ligands. However, these ligands may present some drawbacks, mainly because of their cost and lability. Dye-affinity chromatography overcomes the limitations of biological ligands and is widely used owing to the low cost of synthetic dyes and to their resistance to biological and chemical degradation. In this work, immobilized aminosquarylium cyanine dyes are used in order to exploit affinity interactions with standard proteins such as lysozyme, α-chymotrypsin and trypsin. These studies evaluate the affinity interactions occurring between the immobilized ligand and the different proteins, as a reflection of the sum of several molecular interactions, namely ionic, hydrophobic and van der Waals, spread throughout the structure, in a defined spatial manner. The results show the possibility of using an aminosquarylium cyanine dye bearing a N-hexyl pendant chain, with a ligand density of 1.8 × 10(-2) mmol of dye/g of chromatographic support, to isolate lysozyme, α-chymotrypsin and trypsin from a mixture. The application of a decreasing ammonium sulfate gradient resulted in the recovery of lysozyme in the flowthrough. On the other hand, α-chymotrypsin and trypsin were retained, involving different interactions with the ligand. In conclusion, this study demonstrates the potential applicability of ligands such as aminosquarylium cyanine dyes for the separation and purification of proteins by affinity chromatography.

Monte Carlo simulation of the basic features of the GE Millennium MG single photon emission computed tomography gamma camera

OBJECTIVE

To describe and validate the simulation of the basic features of GE Millennium MG gamma camera using the GATE Monte Carlo platform.

MATERIAL AND METHODS

Crystal size and thickness, parallel-hole collimation and a realistic energy acquisition window were simulated in the GATE platform. GATE results were compared to experimental data in the following imaging conditions: a point source of (99m)Tc at different positions during static imaging and tomographic acquisitions using two different energy windows. The accuracy between the events expected and detected by simulation was obtained with the Mann-Whitney-Wilcoxon test. Comparisons were made regarding the measurement of sensitivity and spatial resolution, static and tomographic. Simulated and experimental spatial resolutions for tomographic data were compared with the Kruskal-Wallis test to assess simulation accuracy for this parameter.

RESULTS

There was good agreement between simulated and experimental data. The number of decays expected when compared with the number of decays registered, showed small deviation (≤ 0.007%). The sensitivity comparisons between static acquisitions for different distances from source to collimator (1, 5, 10, 20, 30 cm) with energy windows of 126-154 keV and 130-158 keV showed differences of 4.4%, 5.5%, 4.2%, 5.5%, 4.5% and 5.4%, 6.3%, 6.3%, 5.8%, 5.3%, respectively. For the tomographic acquisitions, the mean differences were 7.5% and 9.8% for the energy window 126-154 keV and 130-158 keV. Comparison of simulated and experimental spatial resolutions for tomographic data showed no statistically significant differences with 95% confidence interval.

CONCLUSIONS

Adequate simulation of the system basic features using GATE Monte Carlo simulation platform was achieved and validated.

Dose and Time Dependence of Targeted and Untargeted Effects after Very Low Doses of α-Particle Irradiation of Human Lung Cancer Cells

Understanding the effects to human health resulting from exposure to low doses of ionizing radiation is a persisting challenge. No one questions the deleterious consequences for humans following exposure to high radiation doses; however, in the low dose range, the complex and to some extent unknown cellular responses raise important misgivings about the resulting protective or potentially detrimental effects. Bystander effects are involved in low dose exposures, being characterized by the appearance in unirradiated cells of a cellular damage associated with direct radiation exposure. The purpose of our work was to assess, by using clonogenic and micronuclei assays, the dose and time dependence of the bystander response after cells exposure to very low doses of α-particles and to evaluate its importance in the overall induced damage. The study includes an irradiated cells culture, a medium transfer culture with non-irradiated cells and a culture with irradiated cells after centrifugation. We observed a non-negligible contribution of the bystander effects in the overall cellular damage. Low-dose hyper-sensitivity was observed for medium transfer and irradiated cells after centrifugation cultures. Delayed and earlier cellular damage were similar in almost all experiments, suggesting an effectiveness of irradiated medium to induce a bystander response soon after irradiation.

Use of inhaler devices and asthma control in severe asthma patients at a referral center in the city of Salvador, Brazil

OBJECTIVE

To evaluate the use of inhaler devices by patients with severe asthma treated via the Programa para o Controle da Asma e Rinite Alérgica na Bahia(ProAR, Bahia State Asthma and Allergic Rhinitis Control Program), recording the frequency of their errors in performing key steps and the relationship between such errors and the lack of asthma control.

METHODS

A cross-sectional study involving 467 patients enrolled in the ProAR in the city of Salvador, Brazil. The devices evaluated were metered dose inhalers (MDIs), with or without a spacer, and dry powder inhalers (DPIs; Pulvinal® or Aerolizer®). For the assessment of the inhalation technique, a checklist was used; the patients were asked to demonstrate the technique so that an interviewer could observe all of the steps performed. For the assessment of asthma control, we used the 6-item asthma control questionnaire.

RESULTS

Most of the patients showed appropriate inhalation techniques when using the devices. When using an MDI, few patients made mistakes in the key step of "coordinating activation and inhalation" (5.2% and 9.1% with and without the use of a spacer, respectively). During Pulvinal® use, 39% of the patients did not inhale quickly and deeply, compared with only 5.8% during Aerolizer® use. Of the patients that made use of Aerolizer® alone, 71.3% appropriately performed all of the essential steps, and their asthma was controlled.

CONCLUSIONS

Most of the patients in this sample, all of whom had been submitted to periodic checks of their inhalation technique (as part of the program), used the devices appropriately. Proper inhalation technique is associated with asthma symptom control.

Renal transplantation after endovascular aortic aneurysm repair: case report and literature review

An increased number of aortic aneurysms are expected to be diagnosed in chronic renal failure patients awaiting kidney transplantation because of its strong association with atherosclerosis. The development of endovascular aortic aneurysm repair in the 1990s, which is characterized by low morbidity as well as shorter operative time and length of hospital stay, is particularly suited to these patients who are at high risk for conventional surgery. Herein we describe a case of a 58-year-old, man who was diagnosed with a 5.5-cm aortic aneurysm in 2001 and treated with a Gore Excluder (WL Gore and Assoc, Flagstaff, Ariz) aorto-iliac stent-graft. In 2004, he underwent uneventful deceased donor kidney transplantation in the right iliac fossa. With a follow-up of 6 and 9 years, respectively, there is no evidence of an endoleak. The renal function remains normal. This promising new surgical technique has been the subject of only a few published cases. At our center, endovascular aortic aneurysm repair is the first-intention treatment for these patients, as long as it is possible to preserve the iliac arteries for the renal anastomoses and the anatomic conditions are suitable for stent-graft deployment.

Obesity and poor asthma control in patients with severe asthma

BACKGROUND

Asthma is a public health problem as it leads to hospitalization and eventual death, particularly in its severe forms. Many studies have demonstrated an association between obesity and asthma.

OBJECTIVE

The aim of this study was to investigate the relationship between obesity and asthma control in a group of patients at a reference center for severe asthma in Brazil.

METHODS

This cross-sectional study was conducted in the outpatient central reference clinic of the Program for Control of Asthma in the State of Bahia. It included 508 subjects with severe asthma of both genders and above 18 years of age. All the participants answered a sociodemographic and a clinical questionnaire to collect information on their asthma and comorbidities, such as rhinitis and gastro-esophageal reflux disease (GERD). Participants also completed the Asthma Control Questionnaire, performed a spirometry test, and had their weight, height, and waist and hip circumferences registered.

RESULTS

Logistic regression analysis demonstrated a positive association between body mass index (BMI) and uncontrolled asthma [odds ratio (OR) 1.5; 95% confidence interval (CI) 1.02-2.20]. Symptoms of chronic rhinitis and GERD were also significantly associated with uncontrolled asthma (OR 3.68, 95% CI 1.50-9.01; and OR 2.78, 95% CI 1.91-4.03, respectively). There was no correlation between waist-to-hip ratios and asthma control.

CONCLUSION

In our sample of patients with severe asthma, those who were obese were more likely to have uncontrolled asthma than patients with a normal BMI. Nevertheless, this is not conclusive evidence for a direct causal association between obesity and poor asthma control. Future studies are necessary to dissect the relationship between obesity and asthma outcomes.

A decade of the sperm-washing programme: where are we now?

Since 1999, we have treated HIV-positive men with sperm washing as part of a risk-reduction programme with a year-on-year increase in total infectious cycles performed to over 200 in 2008. Four hundred and thirty nine cycles of IUI, 114 cycles of IVF and 117 cycles of ICSI have been performed in HIV positive men over the decade and of the 259 couples treated, a pregnancy rate and ongoing pregnancy rate per couple of 45.4% and 36.3% have been achieved with over 100 children born with no seroconversions. We outline the continued importance of such risk-reduction measures with 9.7% of samples from men with 'stable' disease on anti-retroviral treatment and undetectable viral load demonstrating detectable viral particles in seminal fluid and discuss measures to improve outcome in this patient group.