Ice Hockey Injuries in a Japanese Elite Team: A 3-Year Prospective Study

Context:

As the Asian Ice Hockey League gradually expands and becomes more competitive, ice hockey-related injuries may increase. However, no reports have been published on ice hockey injuries in Japan, including the method of injury and the daily supervision of the players during the regular season.

Objective:

To prospectively study the incidence, types, and mechanisms of ice hockey injuries in an elite Japanese ice hockey team.

Design:

Prospective observational cohort study design.

Setting:

An elite ice hockey team, Tokyo, Japan.

Patients or Other Participants:

Ninety-four players during the 2002–2005 seasons.

Main Outcome Measure(s):

Data were collected for 3 consecutive seasons using an injury reporting form.

Results:

The overall game injury rate was 74.3 per 1000 player-game hours and 11.7 per 1000 player-game hours for injuries resulting in any time loss. The overall practice injury rates were 11.2 per 1000 player-practice hours and 1.1 per 1000 player-practice hours for injuries resulting in any time loss. Forwards had the highest rate of injury, followed by defensemen and then goalkeepers. Contusions were the most common injury, followed by strains, lacerations, and sprains.

Conclusions:

Most injuries among Japanese ice hockey players occurred during games. Game or play intensity may influence the injury rate during games.     

Lipopolysaccharide binding of the mite allergen Der f 2

Lipid-binding properties and/or involvement with host defense are often found in allergen proteins, implying that these intrinsic biological functions likely contribute to the allergenicity of allergens. The group 2 major mite allergens, Der f 2 and Der p 2, show structural homology with MD-2, the lipopolysaccharide (LPS)-binding component of the Toll-like receptor (TLR) 4 signalling complex. Elucidation of the ligand-binding properties of group 2 mite allergens and identification of interaction sites by structural studies are important to explore the relationship between allergenicity and biological function. Here, we report a ligand-fishing approach in which His-tagged Der f 2 was incubated with sonicated stable isotope-labelled Escherichia coli as a potential ligand source, followed by isolation of Der f 2-bound material by a HisTrap column and NMR analysis. We found that Der f 2 binds to LPS with a nanomolar affinity and, using fluorescence and gel filtration assays that LPS binds to Der f 2 in a molar ratio of 1 : 1. We mapped the LPS-binding interface of Der f 2 by NMR perturbation studies, which suggested that LPS binds Der f 2 between the two large β-sheets, similar to its binding to MD-2, the LPS-binding component of the innate immunity receptor TLR4.     

Hepatectomy for Hepatocellular Carcinoma in Elderly Patients Aged 75 Years or More

Background  The aim of this study was to clarify the characteristics of elderly hepatocellular carcinoma (HCC) patients aged 75 years or more who underwent hepatectomy and to clarify whether elderly patients with HCC benefit from hepatectomy. Methods  Between January 1990 and December 2006, 570 patients underwent curative hepatectomy for HCC. Elderly patients were defined as those aged 75 years or more. Clinicopathological data and outcomes after hepatectomy for 64 elderly and 502 younger patients were prospectively collected and compared. Results  The proportion of elderly patients with chronic viral infection was less than that of younger patients (p < 0.001). Cirrhotic patients in the elderly group were less than those in the younger group (p = 0.03). The elderly patients had better liver function than did the younger patients (p = 0.007) but had more advanced HCC with microscopic vascular invasion than did the younger patients (p = 0.04). There was no operative mortality in the elderly patients and there was no significant difference in postoperative complication rates and long-term survival after hepatectomy between the two groups. Conclusions  Hepatectomy for elderly patients with resectable HCC is safe and feasible. Selected elderly patients with HCC might benefit from hepatectomy. This work originated from the Department of Surgery, Division of Frontier Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.     

Airway compression by the ascending aorta due to a thin thoracic cage

An 89-year-old woman with dyspnea and disturbed consciousness due to hypoventilation was admitted to our hospital. Chest radiography showed no abnormal shadow, but she was intubated for deteriorated hypoventilation. Bronchoscopy demonstrated obstruction of the left main bronchus at the carina. Computed tomography (CT) showed neither a mass lesion in the mediastinum nor an aortic aneurysm, but compression of the airway by the ascending aorta was observed. It was thought that the patient’s thin thoracic cage was unable to support the weight of the ascending aorta, which consequently compressed the left main bronchus. After inserting stents into both main bronchi, the patient’s consciousness improved, and respirator support was withdrawn. In aged, bedridden, thin patients with hypopnea or recurrent airway infection, CT and bronchoscopy should be performed to investigate airway patency.     

High oxygen tension prolongs the survival of osteoclast precursors via macrophage colony-stimulating factor

The oxygen tension affects the function, differentiation, and transformation of various cells, including bone cells. In pathological conditions such as rheumatoid arthritis (RA), rapidly destructive arthropathy, and primary or metastatic tumors, severe bone destruction or osteolysis occurs. Abundant blood vessels are often observed around these destructive lesions. At such sites, we have confirmed the increased production of reactive oxygen species (ROS) induced by a high oxygen tension and/or oxidative stress, as well as numerous osteoclasts detectable by immunohistochemistry. These findings suggest that osteoclasts are influenced by the high oxygen tension in pathological bone lesions because the zone around blood vessels has a relatively high oxygen tension. In this study, we investigated the effects of oxygen tension on osteoclastogenesis by culturing human CD14-positive cells (osteoclast precursors) with or without osteoblast-like supporting cells (Saos-4/3 cells) under a normal oxygen tension (20% O(2)) or a high oxygen tension (40% O(2)). A high oxygen tension markedly prolonged the duration of osteoclast precursor formation in the presence of supporting cells, and also markedly and persistently increased the production of macrophage colony stimulating factor (M-CSF) by supporting cells. Furthermore, we found an increase of cells expressing M-CSF and cells positive for tartrate-resistant acid phosphatase (TRAP) in hypervascular destructive bone lesions of RA patients where ROS were also abundant.     

Three-dimensional analysis of computed tomography-based navigation system for total knee arthroplasty: the accuracy of computed tomography-based navigation system

We evaluated the postoperative alignment of 37 primary total knee arthroplasties performed using a computed tomography–based navigation system (Vector Vision Knee 1.5; Brain Lab, Germany) with a new 3-dimensional analysis. The mean coronal femoral angle was 89.0° ± 1.4° (85.5°-92.8°), and the coronal tibial component was 89.2° ± 1.0° (87.4°-91.6°). The hip-knee-ankle angle was observed to be 178.2° ± 1.5° (173.9°-181.8°). The external rotational alignment of the femoral component relative to the surgical epicondylar axis was −0.5° ± 1.7° (−3.2° to 3.4°). The results demonstrated that a computed tomography–based navigation system provided a reasonably satisfactory component alignment. The discrepancy between the 2-dimensional and 3-dimensional evaluations was 1.0° ± 0.9° (0.1°-3.4°). Three-dimensional analysis is necessary to evaluate the accuracy of the navigation system.     

Serum matrix metalloproteinase-3 as a novel marker for risk stratification of patients with nonischemic dilated cardiomyopathy

BackgroundSelective induction of myocardial matrix metalloproteinases (MMPs) has been reported to occur in human nonischemic dilated cardiomyopathy (DCM). We aimed to evaluate the utility of serum MMPs for risk stratification of patients with DCM.Methods and ResultsWe measured serum levels of MMP-2, MMP-3, and MMP-9 using enzyme-linked immunosorbent assay in 71 patients with mild to moderate DCM (left ventricular ejection fraction = 28.3 ± 11.5%). The primary end point was the composite incidence of cardiac death and hospitalizations for worsening heart failure. During the follow-up period (mean, 28 ± 16 months), 19 patients had major cardiac events with sudden cardiac death in 6 cases and hospitalizations for worsening heart failure in 13 cases. Multivariate analysis revealed that MMP-3 and B-type natriuretic peptide were significant independent predictors of cardiac events in patients with DCM (hazard ratio 1.41, P = .012; hazard ratio 2.72, P = .048, respectively). According to the Kaplan-Meier analyses of cumulative cardiac event-free rates of the two groups that were based on the median levels of MMPs, the differences in the cardiac event-free curves were significant only for MMP-3 (P = .009). Moreover, patients with elevations of both MMP-3 and B-type natriuretic peptide were found to have the poorest prognosis.ConclusionOur results may address the utility of serum MMP-3 for risk stratification of patients with DCM.     

Six-month aerobic exercise training ameliorates central sleep apnea in patients with chronic heart failure

BackgroundSleep-disordered breathing (SDB) is common in patients with heart failure and carries an independent risk for poor long-term prognosis. We aimed to study the effects of supervised, aerobic exercise training for 6 months on SDB in patients with chronic heart failure.Methods and ResultsWe enrolled 18 patients having both systolic dysfunction (left ventricular ejection fraction <45%) and SDB (apnea-hypopnea index [AHI] >10). The exercise group comprised 10 patients who participated in our cardiac rehabilitation program for 6 months, and the remaining 8 patients served as control. AHI (median [interquartile range]) was unchanged in the control group patients at 6-month intervals (30.4 [19.9–36.3] versus 36.6 [8.6–39.4], NS). In contrast, AHI was significantly decreased in the exercise group from 24.9 [19.2–37.1] to 8.8 [5.3–10.1] (P < .01). In the exercise group, the numbers of central sleep apnea per night was significantly decreased (152 [124–244] versus 50 [24–67], P < .01) after exercise training, but those of obstructive apnea/hypopnea were unchanged (42 [7–94] versus 18 [7–54], NS). In addition, exercise training significantly increased peak oxygen consumption and decreased minute ventilation to carbon dioxide production slope (both P < .01).ConclusionsSix-month, aerobic exercise training increased exercise capacity and improved central sleep apnea in patients with chronic heart failure from systolic dysfunction.