Clinical application of radial magnetic resonance imaging for evaluation of rotator cuff tear.

BACKGROUND: Magnetic resonance imaging is useful for evaluating the rotator cuff, but some tendinous insertions cannot be assessed using oblique sagittal, oblique coronal, and axial magnetic resonance (MR) images because of the presence of the partial volume effect. HYPOTHESIS: The purpose of this study was to determine whether radial-slice MR images could reveal normal rotator cuff insertions and rotator cuff tears more clearly than conventional MR images. PATIENTS AND METHODS: The study included 18 subjects with normal rotator cuffs and 30 with rotator cuff tears. MR images of rotator cuff insertions sliced into radial, oblique coronal, and axial sections were obtained. The extent to which normal rotator cuff insertions and rotator cuff tears were visualized in each of the three MR images was evaluated. RESULTS: The top to posterior portions of the rotator cuff insertions from 0° to 120° could be visualized in the radial MR images. In comparison, the posterior portions of the rotator cuff insertions could not be visualized around 45° in both the oblique coronal and axial MR images. DISCUSSION: These findings demonstrate that radial MR images are superior to the oblique coronal and axial MR images regarding their ability to accurately visualize rotator cuff insertions. Radial MR images also revealed greater detail around 45° in the posterior area of the rotator cuff tears than the oblique coronal and axial MR images. Radial MR images are particularly useful for visualizing clinically important posterosuperior rotator cuff tears. LEVEL OF EVIDENCE: Level III - Diagnostic study.

Structural changes in dermal collagen and oxidative stress levels in the skin of Japanese overweight males.

OBJECTIVE: It has been reported that obese people have poorly organized dermal collagen structure because of the degradation of collagen fibers, which is caused by an increase in oxidative stress levels associated with the hypertrophy of subcutaneous adipose cells. However, it is unclear whether an increase in oxidative stress levels caused by the accumulation of subcutaneous adipose tissue and a change in the dermal structure also occur in overweight and obese Japanese people. The objectives of this study are to identify structural changes that occur in the dermis and to measure the levels of oxidative stress in Japanese overweight males. METHODS: The overweight group included 43 Japanese male volunteers aged between 25 and 64 years and with a body mass index (BMI) of ≥25 and <30. The control group included 47 male volunteers aged between 22 and 64 years and with BMI of <25. The 20-MHz Dermascan C® ultrasound scanner with software for image analyses was used. Echogenicity of the upper and lower dermis was measured. The mRNA expression level of heme oxygenase-1 (HMOX1) in hair follicles was quantitatively analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) and was used as a marker of oxidative stress. Ultrasonographic imaging and collection of hair follicles were performed at the same site on the thigh, abdomen, and upper arm. RESULTS: The HMOX1 mRNA expression level in the abdomen and thigh was significantly lower in the overweight group than in the control group. Moreover, the echogenicity of the upper dermis of the abdomen and the lower dermis of the abdomen and thigh was significantly lower in the overweight group than in the control group. CONCLUSION: We detected an increase in oxidative stress levels and a decrease in the density of dermal collagen at the same site on the thigh, abdomen, and upper arm of Japanese overweight males. These findings suggest the fragility of the dermis of Japanese overweight males, which might have been caused by the accumulation of subcutaneous adipose tissue.

Living cell-based allergen sensing using a high resolution two-dimensional surface plasmon resonance imager.

Recently, several papers indicated that the surface plasmon resonance (SPR) technique was available to monitor stimulation responses of mammalian cells adhered on sensor chips. On the other hand, the newly developed two-dimensional SPR (2D-SPR) imager system can obtain 2D-images of local refractive index change on the surface of a gold thin film. From these backgrounds, we expected that the 2D-SPR imager can visualize the individual response of many mammalian cells, simultaneously. Here, we report the observation of an allergenic response of a model mast cell, rat basophilic leukaemia cell (RBL-2H3), by using the high magnification 2D-SPR imaging system after pre-sensitization with 0.1 µg mL(-1) anti-dinitrophenyl immunoglobulin E (anti-DNP IgE). The response of the cells was successfully observed as the increment of the SPR signal (reflection intensity) upon stimulation with 0.1-1000 ng mL(-1) DNP-modified bovine serum albumin (DNP-BSA).

Characteristic features of the acetabular labrum in healthy children.

Radial magnetic resonance images of the acetabular labrum were obtained on 40 hips of healthy children. There were no right-left or male-female differences. In children aged 11 years or younger, the labrum on the antero-superior weightbearing portion was triangular in shape, and there was an insular-shaped or linear high-intensity area inside; on the mid-superior portion, the labrum appeared as a regular triangular, low-intensity area; and on the postero-superior portion, it was flat. In children aged 12 and 13 years, the shape of the labrum in each portion was similar to that of the younger children, but the high signal intensity area on the antero-superior portion appeared less frequently. The size of the labrum relative to the femoral head was greater in younger children.

Susceptibility to acyclovir of herpes simplex virus isolates obtained between 1977 and 1996 in Japan.

The susceptibility of genital herpes to acyclovir (ACV) in immunocompetent women was examined, as was the frequency of ACV-resistant viruses by analyzing 56 clinical isolates in Japan between 1977 and 1996. The mean susceptibilities of herpes simplex virus (HSV) type 1 and type 2 were 0.13+/-0.74 and 0.42+/-0.14 microg/ml, respectively, assessed by the 50% inhibitory concentration of plaque formation. The susceptibility to ACV of clinical isolates did not changed since 1977, and also that of nine pairs of HSV-1 and HSV-2 isolates was not affected by ACV treatment. In order to characterize the change in the virus population, the quantitation of the ACV-resistant virus in 10(4) plaque forming units (PFU) of clinical isolates was adopted. The mean frequencies of ACV-resistant viruses per 10(4) PFU for all strains of HSV-1 and HSV-2 were 0.31+/-0.41 and 9.74+/-14.83, respectively, and were not influenced by ACV treatment. Additionally, the phenotypes of ACV-resistance were not influenced by ACV treatment, and more than 90% of ACV-resistant viruses were found to be thymidine kinase-deficient. This study characterized clinical isolates with respect to ACV susceptibility as a population and the quantitative and qualitative characterization of ACV-resistant virus in the virus population of clinical isolates was also studied. The susceptibility of isolates from genital lesions, the frequency of ACV-resistant viruses, and also the phenotypic characterization of ACV-resistant viruses was maintained between 1977 and 1996, even after the introduction of ACV treatment for genital herpes in Japan.

Physiological profile of middle-aged and older climbers who ascended Gasherbrum II, an 8035-m Himalayan peak.

BACKGROUND: The purpose of this study was to investigate the physiological characteristics of a group of middle-aged and older Japanese climbers who ascended Gasherbrum II, an 8035-m peak in the Karakoram Range of the Himalayas. METHODS: Body composition, cardiac structure, and respiratory gas exchange during exercise were estimated in eight climbers with differing levels of experience (seven men and one woman, aged 54 to 63 years) 6 months before their expedition. RESULTS: Using supplementary O2, the four experienced climbers ascended beyond Camp 4 (7400 m) without showing any health problems and were able to attempt the summit. In contrast, the others, who had minimal experience at extreme altitude, suffered from altitude sickness on the way to Camp 4. Body mass index values were relatively high, but their low percentage of body fat (14.9%-21.4%) was indicative of the climbers' substantial lean body weight. Cardiac structures were generally normal, although three experienced male climbers had borderline hypertension and eccentric hypertrophy of the left ventricle. Peak VO2 ranged from 30.9 to 45.6 ml/kg/min, and no significant relationship between fitness level and the success or failure of the ascent was evident. CONCLUSIONS: Even sexagenarians are capable of safely climbing 8000-m peaks with supplementary O2. An exceptionally high fitness level, as is seen in elite older athletes, does not appear to be required. What is essential, however, is moderate fitness, good health, and extensive experience.

Radial magnetic resonance imaging and pathological findings of acetabular labrum in dysplastic hips.

Radial MRI findings and pathological changes were comparatively examined in the acetabular labrum of 11 hips of 11 patients, who underwent total hip arthroplasty for osteoarthritis due to acetabular dysplasia. Diffuse high signal pattern on the radial MR images corresponded to histological degeneration of the labrum. High signal pattern which was equivalent to the synovial fluid, showed an intralabral tear. In the obscure areas of MR images, severe impairment of the labrum such as rupture, detachment, and displacement were found.

Acetabular labrum in hip dysplasia evaluated by radial magnetic resonance imaging.

OBJECTIVE: To numerically express morphologic conditions and signal intensity in the acetabular labrum of the weight-bearing portion of hip joints in patients with hip dysplasia. METHODS: Using a radial magnetic resonance imaging (MRI) technique, where the planes are set radially centered on the midpoint of acetabulum, and which depicts the entire acetabular rim and acetabular labrum, we investigated 60 hip joints of 35 patients with hip dysplasia. RESULTS: The acetabular labrum was larger in dysplastic hips than in normal hips, and the size increased in the posterosuperior portion. All patients had portions with signal intensity changes within the labrum and had impairment on the labrum. When osteoarthrosis due to hip dysplasia was observed, signal intensity changes increased. The changes of intensity varied among the portions observed, and were stronger in the anterosuperior portions than in the superior and posterosuperior portions. CONCLUSION: Radial MRI numerically depicts morphologic conditions of acetabular labrum; the data were usable to evaluate the size difference in acetabular labrum due to hip dysplasia and the degree of impairment.

Radial MRI of the hip with moderate osteoarthritis.

We carried out radial MRI in 30 hips with moderate osteoarthritis and in ten normal hips. On a scout view containing the entire acetabular rim, 12 vertical radial slices were set at 15 degrees intervals. Different appearances were observed in different parts of the joint. In the weight-bearing portion, from 45 degrees anterosuperior to 45 degrees posterosuperior, 'attenuation' (n = 16) and 'disappearance' (n = 25) were observed as abnormalities of the labrum with 'capsular stripping' (n = 29) and 'extraosseous high signal lesion' (n = 27) as capsular abnormalities, seen more often in the anterosuperior portion. In all 12 planes there were osteophytes on the acetabular edge (n = 24), femoral head (n = 22) and/or at the central acetabulum (n = 6), a bone cyst on the acetabulum (n = 18) and/or the femoral head (n = 9), irregularity of the articular cartilage (n = 30), and an effusion (n = 28). Our findings indicate that radial MRI may be a useful non-invasive diagnostic method for demonstrating pathology in moderate osteoarthritis of the hip.

The conformation of alpha-(1-->4)-linked glucose oligomers from maltose to maltoheptaose and short-chain amylose in solution.

The conformation of maltose-type oligomers in water and in dimethylsulfoxide (Me2SO) was studied using two-dimensional NMR spectra. In Me2SO all of the oligomers have a 1a-type conformation. In water, they tend to adopt the same conformation, but the oligomers are looser and more flexible than in Me2SO.

In vitro maturation and ultrastructural observation of cryopreserved minke whale (Balaenoptera acutorostrata) follicular oocytes.

Minke whale (Balaenoptera acutorostrata) follicular oocytes were cryopreserved by a slow-step freezing procedure using ethylene glycol. The morphologically viable proportion of postthawed minke whale follicular oocytes was 39.7%. The maturity of the animals (immature and mature whales) or the presence or absence of cumulus cells (CC) did not affect the proportion of morphologically viable oocytes. Postthawed oocytes were examined for nuclear status after in vitro maturation. The presence of CC (29.1%) significantly enhanced (P < 0.05) the proportion of oocytes at metaphase I/anaphase I/telophase I stages compared to results with the absence of CC (13.5%). A total of 4 of 194 postthawed oocytes matured to the second metaphase stage after culture for 5.5 days with or without CC. The cryopreserved immature oocytes obtained from immature and mature whales were processed to examine the ultrastructure by transmission electron microscopy. Varying ultrastructural damage to the cytoplasm was observed as a result of the cryopreservation procedures. These results show that 20-30% of cryopreserved minke whale follicular oocytes can resume meiosis in vitro, but damage induced by the freezing and thawing procedures was observed.

Bombelli's valgus-extension osteotomy for osteoarthritis due to acetabular dysplasia: results at 10 to 14 years.

Severe osteoarthritis due to acetabular dysplasia (n = 17) was treated with valgus-extension osteotomy, and the patients' clinical outcomes 10-14 years after operation were evaluated according to clinical factors (Japanese Orthopaedic Association hip score; JOA score) and by roentgenography. The mean JOA score 10 years or later had improved by 22 points compared with the preoperative score. On roentgenography, joints which had preoperative roof osteophyte had better postoperative formation of roof osteophyte. The JOA score was higher in the 12 joints which had osteophyte 5 mm or longer than in those joints with osteophyte that was 5 mm or shorter. Postoperative joint space widening occurred in 15 joints (88.2%) 3-6 months postoperatively, and it reached the maximum at 3-5 years. In patients who had a large bone cyst in the femoral head preoperatively, the cyst collapsed, and deformation of femoral head occurred after operation, but remodeling of the joint surface occurred naturally and the congruity improved. In the 6 joints in which the preoperative acetabular head index was less than 60% and the acetabular angle was larger than 30 degrees, the JOA score at 10 years or later was lower than that of the other joints. Based on these findings, valgus-extension osteotomy was evaluated as a useful surgical method for advanced or terminal osteoarthritis in young or middle-aged patients. Predictive factors for long-term prognosis would be the preoperative length of roof osteophyte, joint space widening, and the degree of femoral head covering.

Histological findings of bone marrow edema pattern on MRI in osteonecrosis of the femoral head.

Sequential magnetic resonance imaging (MRI) was performed on a 38-year-old woman with systemic lupus erythematosus who had received corticosteroid and had developed non-traumatic osteonecrosis of the femoral head. The initial MR finding was a band lesion on the T1-weighted image, which had been present before the onset of symptoms. At the onset of symptoms, a diffuse bone marrow edema pattern, with a low signal intensity on T1 and high signal intensity on T2-weighted images, was noted around the band lesion, extending to the femoral neck. Histopathologically, this region was found to consist of serous exudate, focal interstitial hemorrhage, and mild fibrosis, without any evidence of extension of osteonecrosis. It should be noted that extension of a low signal intensity area on MRI after the onset of hip pain may not be the result of the extension of osteonecrosis, but may represent concomitant edema due to collapse.

Radial-sequence magnetic resonance imaging in evaluation of acetabular labrum.

We investigated the usefulness of a radial-sequence magnetic resonance imaging (MRI) technique in the visualization of the acetabular labrum, which surrounds the acetabulum. In 22 hip joints of 12 volunteers, T2-weighted images were obtained on 24 radial planes of the acetabular rim, set at 15 degrees -intervals, using the small tip angle gradient echo method. We examined 7 planes in the weight-bearing portion. The acetabular labrum in the weight-bearing portion was depicted in good contrast to the surrounding tissues. The shape of the labrum differed among individuals and also in the anterior and posterior portions of the labrum. The signal intensity of the labrum was low or partially moderate. There was a high signal intensity band on the base of the acetabular labrum in several portions, which should be carefully interpreted to avoid confusion with abnormality. We concluded that radial-sequence MRI could be a useful technique for evaluation of the condition of the acetabular labrum in the weight-bearing portion.

Effects of exercise training on the heart rate variability and QT dispersion of patients with acute myocardial infarction.

Heart rate variability (HRV) reflects the autonomic tone of the heart, and QT dispersion reflects the regional inhomogeneity of ventricular repolarization. The purpose of the present study was to determine the effects of early exercise training on HRV and QT dispersion in patients with acute myocardial infarction (AMI). Forty patients (mean age: 59 years) with AMI were randomized to training rehabilitation (group Tr, n=20) or conventional rehabilitation (group C, n=20). Two weeks after AMI, group Tr underwent 10 min of exercise using a bicycle ergometer (80% of anaerobic threshold) twice a day. At the end of the second and fourth weeks, 12-lead and 24-h Holter ECGs were recorded. QT intervals were measured and corrected using Bazett's formula (QTc), and QTc dispersion (QTcd) was defined as the difference between maximum and minimum QTc. HRV was accessed by the high-frequency component (HF: 0.15-0.40 Hz) of the HRV power spectrum (parasympathetic activity) and the ratio of low frequency (0.04-0.15 Hz) to HF (L/H ratio: sympathetic activity). In group Tr, HF increased (82.5 to 131.1 ms2), the L/H ratio decreased (3.9 to 2.6), and QTcd decreased (77.2 to 57.2 ms). In group C, none of the indices changed. It was concluded that early exercise training improves sympathovagal balance and decreases QTcd, and may reduce the arrhythmogenic substrate following AMI.

MRI evaluation of the inferior glenohumeral ligament. Comparison with arthroscopic findings in 81 shoulders.

Arthroscopic Bankart repair, using staples, requires a thick and wide anterior band of the inferior glenohumeral ligament. We compared MRI and arthroscopic findings of the ligament in 81 shoulders with traumatic anterior glenohumeral instability. When fluid was present in the shoulder, sensitivity and specificity of the MRI evaluation for the presence of a thick and wide ligament were 82% and 100%, respectively. In shoulders without joint fluid, the condition of the ligament was evaluated according to the presence of a low- or moderate-signal triangle structure on the anterior margin of the glenoid cavity in the 3 MR images obtained from the inferior 2 cm of the glenoid. Sensitivity and specificity of the MRI evaluation in cases without fluid were 84% and 93%, respectively. The MR technique needs to be further improved to achieve better sensitivity for preoperative selection of shoulders suitable for Bankart repair with staples.

Subcellular distribution of 220 kDa antigen in the intercellular spaces of normal human epidermis.

We generated a monoclonal antibody, 7C1, to an extract of pig snout skin used as antigen. The antigen for 7C1 was identified by immunoblotting as a 220 kDa epidermal protein. It was found immunologically to be distributed mainly in the intercellular spaces throughout the living cell layers of normal human epidermis, but its distribution changed in some keratinizing disorders. Study of the association of this protein with subcellular structures by immunoelectron microscopy of normal human skin revealed that it was localized in (1) lamellar granules, (2) intercellular spaces, especially in the lamellar structures derived from the lamellar granules, (3) small vesicles near the cell boundaries and (4) small vesicles in the Golgi apparatus. These results suggest that in humans the 220 kDa protein originates in the Golgi apparatus and is secreted via either the lamellar granules or the small secretory vesicles into the intercellular spaces of the epidermis, where it may be involved in the epidermal permeability barrier function and possibly in keratinizing differentiation.