Radiological evaluation on allograft reconstruction of the acetabulum combined with supporting device in revision total hip replacement.

We reviewed the radiographs of 25 hips of 20 patients who had received revisions of the acetabular components of total hip replacement supplemented by allograft for bone defects. Bone defects in 20 hips (80%) were classified into type D (cranio-central defect) according to Itoman's classification. In eight, sockets were installed directly on the allografts (group A). A metallic supporting device was used for reinforcing the grafts in 17 hips (group B). The position of the acetabular socket was measured on a radiograph, taken immediately after revision surgery and again at the latest follow-up. Using a MEM template, cranial and central migrations were determined. Mean cranial migration in hips of group A was 3.6 mm. Group B was 0.2 mm. Maintenance of thickness of the allografts was 60.6% in the cranial region and 75% in the central in group A. In the hips of group B, however, almost 100% of the initial thickness was maintained cranially and centrally. Allograft reconstruction of acetabular bone defect in revision total hip replacement is a beneficial procedure. The remaining pelvic bone is usually in poor condition, therefore, it is necessary to ensure primary fixation by the metallic supporting device.     

Initial fixation of a finite element model of an AI-Hip cementless stem evaluated by micromotion and stress

Background  

This study investigated issues related to initial stability after stem fixation. Finite element models of the AI-Hip cementless stem were constructed for computer simulation.     

Assessment of inflamed synovial membrane in the knee joint by dynamic magnetic resonance imaging

Dynamic magnetic resonance imaging (dynamic MRI) was used to examine the synovial membrane in the knee joints of 15 patients with rheumatoid arthritis (RA) in order to investigate the relationship between pathological and MRI findings. Signal intensities in the regions of interest (ROI), identified as the synovial membrane of the suprapatellar pouch, were measured on MR images. Signal intensities at various times after the injection of contrast medium Gd–diethylenetriaminopentoacetic acid (Gd–DTPA) were normalized relative to the signal intensity at 80s, and designated as the normalized signal intensity (NSI). Pathological findings were quantified, and the types of inflamed synovial membrane were classified as either acute or chronic. A significant difference in NSI was observed between acute and chronic types (P 0.05). Dynamic MRI was capable of classifying acute and chronic RA by measuring NSI 20s after contrast medium injection. Dynamic MRI was therefore shown to be useful for assessing regional synovial inflammation.     

Alendronate does not prevent long bone fragility in an inactive rat model

The lack of estrogen and inactivity are both important in the pathogenesis of osteoporosis in elderly women, and there have been no appropriate rodent studies to examine the effects of common bisphosphonates on these two components separately. We compared the efficacy of alendronate (ALN) on the long bones of aged female rats, which were sedentary, estrogen deficient, or both. The rats were either forced to remain in a sitting position or allowed to walk in standard cages with or without ALN administration. The 8-week experimental period began 5 weeks after ovariectomy or sham surgery. Parameters of the hindlimb bones were determined by a three-point bending test, peripheral quantitative computed tomography, microfocus computed tomography, confocal laser Raman microspectroscopy, and dynamic histomorphometry. Regardless of ovariectomy, ALN was ineffective against the deterioration of breaking stress caused by sitting even though the trabecular bone mineral density was significantly higher in the sitting–ALN groups. Toughness was significantly deficient in the ovariectomy sitting–ALN group. This was in agreement with the bone geometry with a greater marrow space. Sitting also increased the mineral-to-matrix ratio and the carbonate-to-phosphate ratio, both indicative of aged bone. A greater loss of proteinaceous amide intensity compared with mineral intensity resulted in an increased mineral-to-matrix ratio in the presence of ALN. Sitting resulted in deficits in the quality and the geometry of cortical bone, resulting in fragility. The use of bisphosphonates, such as ALN, may provide a therapy best suited for osteoporotic individuals whose daily activity is not limited.     

Diverse p53 gene aberration in hepatocellular carcinoma detected by dual-color fluorescence in situ hybridization

BACKGROUND AND AIM: In order to evaluate loss of the p53 gene more precisely, we performed dual-color fluorescence in situ hybridization (dual-color FISH) for chromosome 17 and p53 gene together with DNA polymorphism analysis of the p53 gene in hepatocellular carcinoma (HCC). METHODS: Dual-color FISH using probes specific for the centromere of chromosome 17 and the p53 gene was performed for 41 HCC and DNA polymorphism analysis was also performed for them. RESULTS: Of the 34 HCC tested by dual-color FISH, 20 had loss of at least one p53 gene (58.8%). In contrast, of the 32 HCC tested by DNA polymorphism analysis, 23 gave informative results, among which only eight had loss of heterozygosity (LOH) of the p53 gene (34.8%). Notably, among 14 cases positive for loss of the p53 gene by dual-color FISH, seven cases were negative for LOH of the p53 gene. Moreover, dual-color FISH revealed that the percentage of cells that lost at least one p53 gene increased as the HCC became less differentiated (P < 0.01), whereas LOH did not reveal any such correlation. CONCLUSIONS: These data suggest that loss of the p53 gene was present in a considerable number of HCC, and diversity of the p53 gene aberration increases with progression of HCC. Dual-color FISH is an effective method for detection of p53 gene aberration, and it can provide new insight into oncogenesis in HCC.     

Brief Report: Optogenetic regulation of embryo implantation in mice using photoactivatable CRISPR-Cas9

Embryo implantation is achieved upon successful interaction between a fertilized egg and receptive endometrium and is mediated by spatiotemporal expression of implantation-associated molecules including leukemia inhibitory factor (LIF). Here we demonstrate, in mice, that LIF knockdown via a photoactivatable CRISPR-Cas9 gene editing system and illumination with a light-emitting diode can spatiotemporally disrupt fertility. This system enables dissection of spatiotemporal molecular mechanisms associated with embryo implantation and provides a therapeutic strategy for temporal control of reproductive functions in vivo.     

Contributing factors influencing the functional outcome of floating knee injuries

The purpose of the present study was to retrospectively review the floating knee injuries treated at our institute and to determine various factors, such as severity of soft-tissue or skeletal injuries, site of fractures, and treatment methods that may significantly influence the final functional result in these injuries. Between 1986 and 1996, 65 patients with 66 floating knee injuries were treated in our institution. Among 66 fractures of the femur, 19 (29%) were open. There were 43 open tibial fractures. Fifty cases were Fraser type I floating knee fractures, 7 were type IIa, 2 were type IIb, and 7 were type IIc. In 63 cases (95%), both bones had been surgically stabilized with interlocked nails, Ender pins, plates, screws with/without pinning, or external fixations. Final functional results were evaluated according to Karlstr?m and Olerud's criteria. Satisfactory results were rated as cases with excellent or good results. The mean follow-up time was 16.6 months range, (12-50 months). We assessed various factors influencing functional results, including Fraser type, severity of open injury grade (Gustilo) in both fractures, combination of open/closed injuries, fracture types (AO/ASIF type), existence of multiple trauma, neurovascular injuries, polyskeletal trauma, and stabilizing method or operation timing of both fractures. Satisfactory rates in Fraser type I and type II were 64% and 25%, respectively (P= .02). The satisfactory rate in closed, grade I+II, and grade III injuries of the femoral fractures was 53.2%, 81.8%, and 25%, respectively (grade I+II vs. grade III: P < .03). There were no significant correlations between the functional result and the following factors: soft-tissue injuries of the tibia; the fracture pattern of both fractures; the combination of open/closed injuries in each fracture; injury severity score; the existence of neurovascular injuries and double femoral fractures; treatment methods; and operation timing. Severity of damage to the knee joint and open injuries in the thigh were found to be significant factors contributing to the functional outcome in floating knee injuries.     

Analysis of the Genetic Alterations in a Case of Juvenile Multiple Colon Carcinoma With Hypogammaglobulinemia

Background: We have previously reported the clinical characterization of a case of juvenile multiple colorectal carcinoma with hypogammaglobulinemia. Several recent studies have determined that agammaglobulinemia was caused by the loss of Brutons tyrosine kinase (Btk) function. However, any genetic alterations associated with carcinoma formation in individuals with this immunodeficient disease have not been reported.Methods: DNA from eight carcinoma tissues and nine adenoma tissues from this reported case were examined for mutations in p53 by single strand conformation polymorphism analysis, K-ras by mutant allele specific analysis, and replication error or loss of heterozygosity of the TP53 locus on chromosome #17.Results: We found that p53 and K-ras were mutated in the carcinoma tissues. However, each tumor showed unequal and diverse results.Conclusions: The progression of individual tumor was not due to a common genetic event caused directly under the influence of the primary disease at the genetic level.     

Establishment of rat model of acute staphylococcal osteomyelitis: relationship between inoculation dose and development of osteomyelitis

Introduction Many animal models of acute and chronic osteomyelitis have been developed. In these models, osteomyelitic lesions are induced using sclerosing agents and foreign bodies with bacterial strains. In the present rat model, these sclerosing agents were not used. We assessed the relationship between inoculation dose and histological, radiological, and microbiological changes in the acute phase (1 week after inoculation) using this rat osteomyelitis model.Materials and methods An experimental rat model of acute osteomyelitis was developed by direct inoculation of the virulent strain BB of Staphylococcus aureus into tibial bone without sclerosants. To examine the relationship between the inoculation dose of the bacteria and the progression of the osteomyelitis, the inoculated lesions were assessed for changes in histological, radiological, and bacteriological parameters at 1 week after infection. Serial dilutions of the bacteria [6×10¹ to 6×10⁵ colony-forming units (CFU)/5 l] suspended in saline or saline alone were inoculated into the proximal metaphysis of the tibia.Results Development of significant histological and radiological signs of osteomyelitis required an inoculum of at least 6×10³ CFU/5 l. The number of viable bacteria at the lesion reached a maximum of 6×10³ CFU/5 l.Conclusion These results suggest that strain BB induces the development of acute staphylococcal osteomyelitis with clear infective destruction in the tibia, and that our model may be applied to the identification of virulence factors in studies of posttraumatic osteomyelitis.