Serum erythropoietin in cross-country skiers

Serum erythropoietin (Epo) activity, hemoglobin (Hb), and hematocrit (Ht) were determined in 21 cross-country skiers during the training season. The Epo levels were not significantly reduced in the skiers relative to the normal population (P less than 0.01 and P less than 0.001, respectively). In 11 athletes Epo, Ht, urinary gamma-glutamyltransferase, N-acetyl-beta-glucosaminidase, and microalbuminuria were determined before and after a 50-km ski race at 1600 m above sea level. A significant increase of these variables (except for Ht) was found after the competition (P less than 0.001). It is concluded that while the reductions in Hb and Ht, which are typical of several endurance exercises, are not accompanied by a renal hypoxia sufficient to stimulate Epo overproduction, the renal hypoxia reached during the strenuous exercise of the race at altitude may be effective in determining blood increases in Epo.     

Angiogenic response induced by acellular aortic matrix in vivo

In this study, we investigated the angiogenic response induced by acellular aortic matrices implanted in vivo onto the chick embryo chorioallantoic membrane (CAM), a useful model for such investigation. Results showed that acellular matrices were able to induce a strong angiogenic response comparable to that of fibroblast growth factor 2 (FGF-2), a well-known angiogenic cytokine. The angiogenic response was further increased when exogenous FGF-2 or transforming growth factor beta 1 (TGF-beta1) were added to the matrices and inhibited by the addition of an anti-FGF-2 or anti-TGF-beta1 antibodies. The response may be considered dependent on a direct angiogenic effect exerted by the matrices and in part also by the presence of FGF-2 and TGF-beta1 in the acellular matrices.     

Novel osteoblast-adhesive peptides for dental/orthopedic biomaterials

Next generation dental/orthopedic biomaterials must be designed to enhance and support osteoblast adhesion. The osteoblasts use different ways to adhere, that is, integrin- and proteoglycan-mediated mechanisms. The present study reports on the synthesis and osteoblast-adhesive properties of peptides carrying RGD motifs and of sequences mapped on human vitronectin. Our data suggest that osteoblast adhesion on polystyrene plates modified with a linear peptide, in which the GRGDSP sequence is repeated four times, was significantly higher when compared to the adhesion obtained using branched peptides, interestingly containing the same motif. Osteoblast adhesion assays on acellular bone matrix using this active peptide gave very promising results. We also demonstrated that a novel peptide, carrying the X-B-B-B-X-B-B-X motif (where B is a basic amino acid and X is a nonbasic residue), promotes proteoglycan-mediated osteoblast adhesion more efficiently with respect to the KRSR sequence that was recently proposed as heparan-sulfate binding peptide.     

New anatomical reference systems for the bones of the foot and ankle complex: definitions and exploitation on clinical conditions

Medial tibial stress syndrome (MTSS) is one of the most common lower leg injuries in sporting populations. It accounts for between 6 and 16% of all running injuries, and up to 53% of lower leg injuries in military recruits. Various treatment modalities are available with varying degrees of success. In recalcitrant cases, surgery is often the only option. To evaluate whether ultrasound-guided injection of 15% dextrose for treatment of recalcitrant MTSS decreases pain and facilitates a return to desired activity levels for those who may otherwise be considering surgery or giving up the sport. The study design was a prospective consecutive case series involving eighteen patients: fifteen male and three female; (mean age = 31.2 years) with recalcitrant MTSS. They were referred from sports injury clinics across the UK, having failed all available conservative treatment. An ultrasound-guided sub-periosteal injection of 15% dextrose was administered by the same clinician (NP) along the length of the symptomatic area. Typically, 1 mL of solution was injected per cm of the symptomatic area. Pain was assessed using a 10-cm visual analog scale (VAS) at baseline, short-term, medium-term (mean 18 weeks), and long-term (mean 52 weeks) follow-up. Symptom resolution and return to activity were measured using a Likert scale at medium and long-term follow-up. Statistical analyses were performed using SPSS for Mac version 19.0.0 (IBM, New York, NY, US). The Shapiro-Wilk test was used to evaluate the normality of the distribution of data. Friedman’s non-parametric test was used to compare the within-patient treatment response over time. Post-hoc Wilcoxon signed-rank tests with Bonferroni corrections were performed to determine VAS average pain response to treatment over five paired periods. Patients reported a significant (p < 0.01) reduction in median VAS pain score at medium and long-term follow-up compared to baseline. Median improvement per patient was 4.5/10. Patients rated their condition as ‘much improved’ at medium-term follow-up and the median return to sports score was ‘returned to desired but not pre-injury level’ at medium-term and long-term follow-up. No adverse events were reported. Ultrasound-guided 15% dextrose prolotherapy injection has a significant medium-term effect on pain in MTSS. This benefit may be maintained long-term; however, more robust trials are required to validate these findings in the absence of controls. Clinicians should consider the use of ultrasound-guided injection of 15% dextrose as a viable treatment option to reduce pain and aid return to activity for patients with recalcitrant MTSS.     

Short bowel syndrome: experimental approach to increase intestinal surface in rats by gastric homologous acellular matrix

BACKGROUND/PURPOSE: In this preliminary work the authors used homologous acellular matrix obtained by the gastric wall to increase the small bowel surface in Sprague-Downey rats; through this experimental model the authors verified that homologous acellular matrix can support cell migration and the reconstruction of the intestinal wall. METHODS: A tract of about 2 cm of tubular gastric acellular matrix was inserted with bilateral anastomosis in an isolated ileal loop, which was located in endoabdominal position through a short subcutaneous tunnel. Twelve animals were analyzed at each of the time-points ranging from 1 to 6 weeks after surgery. RESULTS: Histologic evaluation showed that the implanted matrix can be reintegrated in the normal small bowel in a period ranging between 3 and 6 weeks from surgery. The implanted matrix was organized with 4 different tonacae from the third week after the surgery, without interruption at the site of the anastomosis. CONCLUSIONS: To date, the authors do not have a demonstration of the function of the ileal loop reconstructed with this technique; based on these results the authors are engaged in an experimental trial of restoration of intestinal viability with the ileal prosthesis after 3 weeks to study its function.     

Human herpesvirus type 8-associated primary lymphomatous effusion in an elderly HIV-negative patient: clinical and molecular characterization

Primary lymphomatous effusions are defined as lymphomas presenting in the serous body cavities in the absence of clinically identifiable tumor masses. Recently, a peculiar type of primary lymphomatous effusion associated with tumor clone infection by human herpesvirus type 8 (HHV-8) and preferentially arising in HIV-positive patients has been described and termed as primary effusion lymphoma (PEL). This report describes a case of PEL which has developed in a HIV-negative, 92-year-old man with longstanding Mediterranean Kaposi's sarcoma, a disease also associated with HHV-8 infection. The patient presented with pleural and ascitic effusions in the absence of solid masses within the lungs, mediastinum, thoracic wall or abdominal cavity. The effusions consisted of malignant lymphocytes with morphologic features bridging immunoblastic and anaplastic cells. Immunophenotypic studies revealed that the lymphoma population expressed an antigenic profile consistent with PEL, i.e. the absence of common B- and T-cell markers (non-B, non-T phenotype) coupled to CD138 positivity. Molecular analysis demonstrated infection of the tumor clone by HHV-8 as well as monoclonally rearranged immunoglobulin genes, consistent with a B-cell histogenesis of the lymphoma. In addition, this PEL case harbored PAX-5 gene mutations, which have been recently demonstrated as a key feature of the proto-oncogene hypermutation process involved in the pathogenesis of some lymphoma types. Following two courses of etoposide and prednisone, a partial remission was achieved. The patient died of liver failure 3 months after the diagnosis of PEL. Overall, this case report illustrates the need for an integrated diagnostic approach based on clinical features, morphology, immunophenotype, and molecular genetics to primary lymphomatous effusions.     

Association between VO2 peak estimated by a 1-km treadmill walk and mortality. A 10-year follow-up study in patients with cardiovascular disease

Purpose

The aim of this study is to assess the association between peak oxygen uptake (VO₂ peak), determined using a perceptually regulated 1-km walking test (1 k-TWT), and all-cause mortality in cardiac patients.

Methods

1255 male patients, aged 25–85 years, completed a moderate 1 k-TWT to estimate VO₂ peak. Subjects were followed for all-cause mortality for up to 10 years. Cox proportional hazard models were employed to determine variables associated with mortality. Based on the estimated VO₂ peak, the sample was subdivided into quartiles and mortality risks were calculated. To assess the discriminatory accuracy of the estimated VO₂ peak for estimating survival, receiver-operating-characteristics curves were constructed.

Results

During a median 8.2 year follow-up, a total of 141 deaths from any cause occurred, yielding an average annual mortality of 1.4%. The strongest predictor of all-cause mortality was the estimated VO₂ peak (c-statistic 0.71, 95% confidence intervals: 0.69–0.74, P < 0.0001). Survival decreased in a graded fashion from the highest estimated VO₂ peak quartile to the lowest quartile. Compared to the lowest quartile, the hazard ratios (95% confidence intervals) for the second, third, and fourth quartiles were 0.77 (0.35–1.33), 0.43 (0.20–0.91), and 0.16 (0.05–0.54) respectively (P for trend < 0.0001). An 89% reduction in mortality risk was observed among a subset of subjects in the fittest quartile who improved their estimated VO₂ peak over the follow-up period relative to subjects in the least fit quartile who did not improve.

Conclusion

VO₂ peak estimated by a novel 1 k-TWT predicts survival in subjects with stable cardiovascular disease.     

Guided walking is more effective than suggested walking in reducing the blood pressure of hypertensive sedentary subjects and in modifying their lifestyle

Sport Sciences for Health - The study has compared the effects of a program of guided walking (GW) and of a program of suggested walking (SW) on the blood pressure and on the lifestyle of sedentary...