Penetration of linezolid into rabbit intervertebral discs and surrounding tissues

Linezolid belongs to a new class of synthetic antimicrobial agent that is effective for a variety of methicillin-resistant Staphylococcus aureus (MRSA) infections including bone and joint MRSA infections, but the effectiveness of linezolid for the treatment of MRSA spine infection remains controversial. In this study, we investigated the diffusion of linezolid or vancomycin into normal rabbit spinal tissues to determine the adequacy of linezolid for the treatment of spinal infection. The penetration efficacy of linezolid into the annulus fibrosus, nucleus pulposus, and vertebral bone (10, 8, and 10%, respectively) was lower than that of vancomycin (27, 11, and 14%, respectively). The penetration efficacy of linezolid into the bone marrow and iliopsoas muscle (88 and 84%, respectively), however, was higher than that of vancomycin (67 and 9%, respectively). These results suggest that linezolid is inadequate for the treatment of spine infection limited to the intervertebral disc, but may be effective for the treatment of infection extending into the muscle and bone marrow, such as in vertebral osteomyelitis, iliopsoas abscess, and postsurgical infection.     

New treatment method for developmental dysplasia of the hips after walking age: arthroscopic reduction with limboplasty based on the findings of preoperative imaging

Background  

What makes treatment choice for developmental dysplasia of the hips diagnosed after walking age difficult is the poor understanding of prereduction conditions that obstruct the reduction in spatial terms. To evaluate these problems, we employed subtraction three-dimensional imaging to search for the factors involved in intraarticular obstruction. On the basis of the findings of preoperative subtraction threedimensional imaging from computed tomography, we developed a new method, a minimum invasive arthroscopic reduction with limboplasty, for reduction of developmental dysplasia of the hips after walking age. The purposes of this report were to: (1) describe the technique of the arthroscopic procedure, and (2) evaluate our new method using radiographic parameters.     

Measurement of subclavicular pressure on the subclavian artery and brachial plexus in the costoclavicular space during provocative positioning for thoracic outlet syndrome

Background  

Thoracic outlet syndrome is thought to be caused by compression of the brachial plexus or subclavian artery in the interscalene, costoclavicular, or subcoracoid space. Some provocative tests are widely used for diagnosing thoracic outlet syndrome. However, whether provocative positions actually compress the neurovascular bundle in these spaces remains unclear. The purpose of this study was to investigate the possibility of neurovascular bundle compression in the costoclavicular space by measuring the pressure applied to the brachial plexus and subclavian artery in provocative positions.     

Effects of 1‐O‐hexyl‐2,3,5‐trimethylhydroquinone on carbon tetrachloride‐induced hepatic cirrhosis in rats

Aim: The present study was undertaken to evaluate the effects of 1‐O‐hexyl‐2,3,5‐trimethylhydroquinone (HTHQ), a synthesized vitamin E derivative, on carbon tetrachloride (CCl₄)‐induced cirrhosis. Methods: Rats were treated with hypodermic injections of CCl₄ twice a week to induce the hepatic cirrhosis, and given drinking water containing HTHQ or solvent. Primary cultures of rat hepatocytes were performed to evaluate the effects of HTHQ on the expression of inducible nitric oxide synthase (iNOS). Results: Masson's staining of rat livers showed fibrosis around pseudo‐lobules in the CCl₄ group, the lesions being reduced in the CCl₄ HTHQ group. Increases in liver tissue hydroxyproline and α₁(I) collagen, α‐smooth muscle actin and iNOS induced by CCl₄, were also markedly diminished by HTHQ. Furthermore, both HTHQ and vitamin E attenuated interleukin‐1β‐induced iNOS protein expression in cultured hepatocytes, the potency of HTHQ being 10‐times higher than that of vitamin E. Conclusion: HTHQ may inhibit development of hepatic cirrhosis in rats, more potently than vitamin E, by inhibiting the iNOS expression in hepatocytes. Because vitamin E has a radical scavenging action, roles of NO and peroxynitrite will be discussed in the effects of HTHQ on the fibrosis.     

Periodic fever and erythema nodosum associated with MDS with trisomy 8: report of two cases and review of the literature

We report two cases of myelodysplastic syndrome (MDS) with trisomy 8 who had periodic fever and erythema nodosum (EN). A 74-year-old man showed periodic fever and EN. A diagnosis of MDS with trisomy 8 was made, and he was successfully treated with prednisolone (PSL). A 71-year-old man presented with intermittent fever, EN, and recurrent elevation of myogenic enzymes. Despite sustained inflammation, laboratory tests showed macrocytic anemia and thrombocytopenia. Marrow aspiration showed MDS with the chromosomal abnormality trisomy 8. He was successfully treated with PSL without repeated transient fever and elevation of creatine kinase. The results of a literature review of 35 cases of MDS with trisomy 8 and Behçet’s disease-like symptoms, such as EN, oral ulcer and intestinal ulcer, suggest that the disease entity of “trisomy 8 syndrome” may be considered, and that it is an important differential diagnosis of periodic fever and EN.     

A case of neurosarcoidosis with necrotizing granuloma expressing angiotensin-converting enzyme

We described a case of neurosarcoidosis with necrotizing sarcoid granulomatosis in a 22-year-old man. Contrast-enhanced brain computed tomography scan and magnetic resonance imaging showed intracerebral multiple nodular lesions. Noncaseating and partial necrotizing granulomas were detected in the specimen resected by neurosurgery. In addition, immunohistochemical examination revealed the expression of angiotensin-converting enzyme in necrotizing granuloma. Thus, these findings were consistent with neurosarcoidosis. Clinical and pathological presentation, immunological features, and treatment modalities of neurosarcoidosis are discussed.     

Correlation between MMP-13 and HDAC7 expression in human knee osteoarthritis

Recent studies suggest that histone deacetylase (HDAC) inhibitors may therapeutically prevent cartilage degradation in osteoarthritis (OA). Matrix metalloproteinase-13 (MMP-13) plays an important role in the pathogenesis of this disease and in the present study we investigated the correlation between HDACs and MMP-13. Comparing the expression of different HDACs in cartilage from OA patients and healthy donors, HDAC7 showed a significant elevation in cartilage from OA patients. High level of HDAC7 expression in OA cartilage was also confirmed by immunohistochemistry. Knockdown of HDAC7 by small interference RNA (siRNA) in SW1353 human chondrosarcoma cells strongly suppressed interleukin (IL)-1-dependent and independent induction of MMP-13 gene expression. In conclusion, elevated HDAC7 expression in human OA may contribute to cartilage degradation via promoting MMP-13 gene expression, suggesting the critical role of MMP-13 in OA pathogenesis.     

Quadriceps sarcopenia and visceral obesity are risk factors for postural instability in the middle‐aged to elderly population

Aim: Aging shifts body composition to comprising more fat and less muscle. Sarcopenia, particularly in the knee extensors, and obesity, particularly visceral obesity, either alone or in combination, may exacerbate age‐related physical disability. We investigated the association between age‐related quadriceps (Qc) sarcopenia and visceral obesity, as measured by cross‐sectional area (CSA), on postural instability. Methods: Mid‐thigh muscle CSA and abdominal visceral and subcutaneous fat area at the level of the umbilicus were assessed from computed tomography (CT) images in 410 apparently healthy independent middle‐aged to elderly subjects attending the medical check‐up program in Ehime University Hospital. Static postural instability using a posturograph and one‐leg standing time with eyes open were assessed. Results: Both abdominal visceral fat area and Qc muscle CSA corrected by body weight (BW) were associated with static postural instability, in addition to age and sex, while BW‐corrected Qc muscle CSA predicted a short one‐leg standing time. The combination of Qc sarcopenia, defined as greater than 1 standard deviation below the mean of a young group (age <60 years), and visceral obesity, defined as a visceral fat area of more than 100 cm², were associated with static postural instability, while Qc sarcopenia was related to a higher prevalence of one‐leg standing time of less than 30 s, irrespective of visceral obesity. Conclusion: Thigh Qc sarcopenia and visceral obesity are associated with postural instability in middle‐aged to elderly subjects. These findings suggest that age‐related, site‐specific fat and muscle mass alterations are associated with functional impairment. Geriatr Gerontol Int 2010; 10: 233–243.     

Associations between short one‐leg standing time and speed of sound of calcaneal bone in a general population: The Shimanami Health Promoting Program (J‐SHIPP) study

Aim: Loss of bone mass is a major cause of fracture in the elderly. One‐leg standing (OLS) time has been postulated to be predictive of reduced bone mass. Here, we conducted a cross‐sectional study to clarify whether OLS time measurements are associated with the speed of sound (SOS) of calcaneal bone independent of muscle mass in the lower extremity, a major confounding factor for the association, in a community‐dwelling population of middle‐aged to elderly subjects. Methods: The study subjects consisted of 770 apparently healthy middle‐aged to elderly community‐residents. Quantitative assessment of calcaneal bone was done using a quantitative ultrasound technique. OLS time with eyes open was measured with a maximum time of 60 s. Femoral muscle cross‐sectional area (CSA) was measured from a computed tomography image. Results: Subjects who could not stand 60 s on one leg (n = 192) showed significantly lower SOS (1487 ± 20, 1501 ± 24 m/s, P < 0.001). In addition, femoral muscle CSA was positively associated with SOS (male, r = 0.148, P < 0.01; female, r = 0.204, P < 0.001). However, multiple regression analysis adjusted for age, sex and muscle CSA identified short OLS time less than 60 s as an independent determinant of SOS in both male (P < 0.001) and female (P < 0.05) subjects. OLS time was significantly associated with posturograph‐measured mobility of the center of gravity. However, multiple regression analysis showed no significant correlation between balance impairment and SOS (P > 0.1). Conclusion: OLS time less than 60 s was significantly associated with reduced SOS independent of age, sex and muscle mass in the lower extremity.