Changes in muscle morphology in dialysis patients after 6 months of aerobic exercise training.

BACKGROUND: In the present study we investigated the effect of a 6-month aerobic exercise programme on the morphology of the gastrocnemius muscle of end-stage renal disease (ESRD) patients. METHODS: Twenty-four ESRD patients volunteered to participate in the training programme and underwent muscle biopsy before training. Eighteen patients completed the training programme of whom nine agreed to a post-training biopsy (one woman and eight men, mean age 56 +/- 15 years). Data are presented for the nine subjects who were biopsied before (PRE) and after training (POST) and separately for the 15 subjects for whom we only have a biopsy before training (cross-sectional group). RESULTS: There were no significant differences (P > 0.05) in fibre type distribution or myosin heavy chain (MyHC) expression between the cross-sectional and PRE/POST groups. The mean cross-section fibre area after training (POST) increased by 46% compared with the PRE training status (P < 0.01). The proportion of atrophic fibres decreased significantly after training in type I, IIa and IIx fibre populations (from 51 to 15%, 58 to 21% and 62 to 32%, respectively). Significant differences were also found in capillary contact per fibre (CC/F), with the muscle having 24% (P < 0.05) more CC/F compared with the PRE training status. No significant differences in cytochrome c oxidase concentration were found between the groups. CONCLUSIONS: In conclusion, exercise appeared to be beneficial in renal rehabilitation by correcting the fibre atrophy, increasing the cross-section fibre area and improving the capillarization in the skeletal muscle of renal failure patients.     

Measurements of primary off-axis ratios in wedged asymmetric photon fields: a formalism for dose and monitor unit calculations

Asymmetric collimators or heavily blocked fields with physical wedges are still encountered in daily practice. In such cases, a reliable dosimetry system is necessary to perform manual dose and monitor unit calculations in order to independently verify the calculations of commercial treatment planning systems. In this work, primary wedged off-axis ratios (POAR(w)s) that account for changes in the beam intensity along both the wedge gradient and perpendicular directions of the photon field, when asymmetric collimators are applied, were measured experimentally at specific depths. The measurements were made in phantom with an ion chamber along the wedge gradient and the perpendicular directions under 'good geometry' conditions. A consistent formalism was presented that could easily be implemented in the clinical environment as an independent verification of the calculations by a treatment planning system. The accuracy of the method was found to be dependent on the specific wedge used, off-axis distance and depth in the phantom. In our study, the accuracy was within 2% in most cases for both energies. We concluded that the primary wedged off-axis ratios when used along with open symmetric field dosimetric parameters could provide adequate accuracy for manual monitor unit calculations.     

Short-term effectiveness of a community-implemented falls prevention referral service

Purpose: To evaluate the effectiveness of the 16-week evidence-based Steady Steps exercise referral scheme at improving physical function, balance confidence, and quality of life (QoL) of community-dwelling older adults at risk of falling.

Method: A non-experimental, practice-based study involving a retrospective analysis of participant outcomes. Pre–post comparisons of three performance-based measures of gait and balance and of person-reported outcomes for balance confidence and QoL were performed. Effectiveness was evaluated in terms of statistically significant changes and relative to published fall-risk thresholds and minimal detectable changes (MDCs) or minimum clinically important differences.

Results: One hundred and thirty-six participants completed the program over 19?months. Statistically significant differences were observed for all outcomes (p?40% reported clinically important improvements in QoL.

Conclusions: While the non-experimental design precludes conclusive evidence of causation, the highly significant and clinically meaningful improvements observed in individuals who completed the evidence-based Steady Steps program support its translation of evidence into effective practice. Continued implementation and evaluation of such practices and their longer-term effects are warranted.

• Implications for Rehabilitation

• Falls in older adults represent an escalating public health problem, and rehabilitation professionals are charged with developing and/or identifying feasible and effective evidence-based programs that target and reduce falls risk in this population.

• Our findings support Steady Steps as an effective third-sector referral rehabilitation service that successfully translates research evidence-based exercise interventions into effective practice, positively impacting physical function, balance confidence and quality of life (QoL) in community-dwelling older adults.

• Our study provides practice-based evidence of the effectiveness of exercise interventions that are progressively challenging, deliver a high dose of moderate to high intensity and target the main falls risk factors of muscle weakness and gait and balance impairment.

• In spite of their limitations, non-experimental, practice-based approaches provide rehabilitation professionals with feasible opportunities for evaluating existing services, such as Steady Steps, and contributing to the overall evidence-base for falls prevention and management.

     

Serologic markers of persistent Chlamydia pneumonia infection and long-term prognosis after successful coronary stenting

Background

Previous studies have shown an incremental role of inflammation in late prognosis following coronary stenting (CS). In particular, high preprocedural levels of plasma C-reactive protein (CRP) have been related to increased hazard of late ischemic complications. Persistent Chlamydia pneumoniae (Cp) infection, detected by positive IgA anti-Cp titers, may be associated with this inflammatory process and portend a high risk of late adverse prognosis after CS.

Methods

A total of 483 consecutive patients with either stable or unstable coronary syndromes were followed-up for 1 year after successful CS. The composite of cardiac death, myocardial infarction, rehospitalization for rest-unstable angina, and exertional angina, whichever occurred first, was the clinical end point. Additionally, the rate of in-stent restenosis and progression of coronary artery disease during this period were evaluated. Anti-Cp titers and plasma CRP levels were measured before the procedure.

Results

Positive immunoglobulin A (IgA), but not positive immunoglobulin G (IgG), titers were significantly associated with high plasma CRP levels in patients with unstable coronary syndromes (P = .005), but not in those with stable angina (P = .7). Moreover, positive IgA titers were significantly related to increased risk of both the composite clinical end point (P = .04) and progression of coronary artery disease (P < .001) in patients with unstable coronary syndromes but not in those with stable angina. Neither positive IgA nor positive IgG titers were associated with the rate of in-stent restenosis.

Conclusions

Persistent Cp infection may drive an inflammatory response in the coronary vasculature and portends an adverse late outcome after CS in patients with unstable coronary syndromes.     

Laryngeal leiomyosarcoma: a case report and review of the literature

Laryngeal leiomyosarcoma (LLM) is a rare malignancy originating from the smooth muscles of blood vessels or from aberrant undifferentiated mesenchymal tissue. Histological diagnosis may be particularly difficult and correct diagnosis is based on immunohistochemical investigations and electron microscopy. A case report of a LLM in a 74-year-old man is presented. Direct laryngoscopy revealed a large glottic lesion causing airway compromise and an emergency tracheotomy was performed. Subsequent total laryngectomy confirmed the diagnosis of leiomyosarcoma. Lung metastases developed 8 months following treatment, despite the absence of local or regional recurrence, and the patient died 3 months later. A review of the English and French literature revealed 30 previous cases of LLM. Clinical presentation, histological diagnosis, and management of this rare malignancy are analyzed aiming to improve our knowledge regarding the best treatment modality.     

Surface tension of still wines in relation to some of their constituents: A simple determination of ethanol content

An attempt is made in this work to establish a correlation between surface tension and analytical characteristics of still wines, with the aim of predicting mainly their ethanol, protein and tannin concentrations. First, model solutions of ethanol, bovine serum albumin protein (BSA) and tannins were prepared and their surface tension measured. Second, the analytical characteristics of 20 still white and red wines from Hellenic grape varieties were determined, using methods of titration, liquid and gas chromatography (HPLC and GC/FID) and spectrophotometry (UV–vis and FTIR). For the surface tension measurements of both model solutions and wine samples, the Wilhelmy plate technique was applied. Statistical analysis of the results showed that 12 enological parameters were highly correlated with surface tension. Ethyl alcohol, proteins, tannins, potassium, sodium, total phenols and methanol, as well as the volatile acidity and pH of the wines, exhibited negative correlation; while total SO₂ and malic acid had positive correlation coefficients at a confidence level of 95%. The best linear model was obtained for the ethanol content, as it can predict by 91.4% the alcoholic strength of a wine based solely on its surface tension. This work, for the first time, provides a simple and fast way of estimating the value of such an important enological parameter.     

Infrequent genetic alterations of the tumor suppressor gene PTEN/MMAC1 in squamous cell carcinoma of the oral cavity

BACKGROUND: Fifty tumor specimens from primarily untreated patients were analyzed to elucidate the involvement of the tumor suppressor gene PTEN/MMAC1 in the development of oral squamous cell cancer. METHODS: Eight microsatellite markers, spanning 10 cM of genomic DNA located centromeric, telomeric or intragenic of PTEN/MMAC1 were used for loss of heterozygosity (LOH) and breakpoint analysis. The microsatellite panel within or in close proximity (1 cM) to the 10q23.3 locus showed a LOH rate of 12%. Complete sequence analysis of the genes coding region was performed in all 10 cases that exhibited LOH in one of the eight microsatellite markers within or around the PTEN/MMAC1 gene. Comparative multiplex PCR reactions served to screen for homozygous deletions. RESULTS: There was no association between allelic loss of the gene, overall patient survival and recurrence-free survival. Sequencing did not reveal any mutation in the coding region of PTEN/MMAC1. Differential PCR analysis failed to detect any homozygous deletion. CONCLUSIONS: We conclude that PTEN/MMAC1 gene alterations do not play a key role in tumorigenesis of oral squamous cell cancers.