Hydroxyapatite-coating of pedicle screws improves resistance against pull-out force in the osteoporotic canine lumbar spine model: a pilot study.

BACKGROUND CONTEXT: In patients with spinal osteoporosis, the early achievement and maintenance of a biological bond between the pedicle screw and bone is important to avoid screw loosening complications. There are few reports of in vivo investigations involving biomechanical and histological evaluations in the osteoporotic spine. PURPOSE: To evaluate the effect of hydroxyapatite (HA)-coating on the pedicle screw in the osteoporotic lumbar spine and to investigate the relationship between resistance against the screw pull-out force and bone mineral density (BMD) of the vertebral body. STUDY DESIGN/SETTING: Mechanical and pathological investigations in the lumbar spine. METHODS: Two 24-month-old female beagle dogs were fed a calcium-free dog chow for 6 months after ovariectomy (OVX). BMD (in g/cm2) was measured by dual energy X-ray absorptiometry at pre-OVX and 6 months after OVX. Pedicle screws were placed from L1 to L6 at 6 months after OVX. Twenty-four pure titanium cortical screws (Synthes, #401-114) were used as pedicle screws (Ti-PS). Of these, 12 screws had HA-coating (HA-PS). The HA-PS screws were inserted into the right pedicles and the Ti-PS were inserted into the left pedicles. Ten days after this procedure, the lumbar spines were removed en bloc for screw pull-out testing and histological evaluation. RESULTS: The mean BMD value of the lumbar vertebrae 6 months after the OVX was 0.549+/-0.087 g/cm2, which was significantly less than the pre-OVX mean BMD of 0.603+/-0.092 g/cm2 (p < 0.001). The mean resistance against the pull-out force for the HA-PS was significantly greater at 165.6+/-26.5N than in the Ti-PS (103.1+/-30.2N, p < .001). The histological sections in the HA-PS clearly revealed new bone bonding with the apatite coating but only fibrous tissue bonding in the Ti-PS. CONCLUSIONS: The results of this study showed that the resistance to the pull-out force of HA-PS is 1.6 times that of Ti-PS. Furthermore, HA-PS has superior biological bonding to the surrounding bone, as early as 10 days after surgery in this osteoporotic spine model. Thus, in patients with osteoporosis, coating of the pedicle screw with HA may provide better stability and bonding between the pedicle screw and bone in the early postoperative period.     

Assessment of SPECT ventilation-perfusion imaging in patients with lung cancer

Ventilation and perfusion SPECT images during tidal breathing were studied in 15 cases of lung cancer using ^81mKr gas and ^99mTc-microspheres. Furthermore, functional images of V/Q ratio and Q/V ratio were prepared, and their clinical significance is descussed with reference to general lung function. There was a decreas in %VC and %FEV _1.0in 7 of 15 cases, and an increase of AaDo₂ in the blood gas analysis in 12 of 15 cases. Both planar and SPECT images showed ventilation and perfusion abnormalities in all 15 cases. Of these, 12 patients showed matched ventilation and perfusion defects, 2 patients a dead-space effect and 1 patient a shunt effect. In comparing planar and SPECT images, depiction of ventilation and perfusion impairments were equally clear in 11 cases, but in 3, showing a lobar or segmental defect with a shunt effect, the SPECT images were superior. In a patient with markedly impaired function of the affected lung, the remaining function could not be depicted by SPECT. From the above, it seems that better information can be obtained for understanding the ventilation and perfusion states of lung cancer by adding the SPECT images to the planar image.     

Anterior interosseous nerve palsy after reduction and percutaneous pinning of open fractures of the radius and ulna.

We report a case of an anterior interosseous nerve palsy after closed reduction and percutaneous pinning of open fractures of the radius and ulna in an adult. Operative findings showed that the anterior interosseous nerve was trapped between the distal and proximal part of the fractured radius. Treatment by neurorrhaphy gave a satisfactory result.     

Clinical usefulness of the frontal assessment battery (FAB) for elderly in memory clinic]

To investigate the usefulness of the frontal assessment battery (FAB) as a brief assessment for diagnosis in patients with dementia, we examined cognitive function using the FAB, Mini-mental state examination (MMSE), Kana-hiroi test, and Raven's colored progressive matrices (RCPM). Subjects were 82 senile patients having amnesia as a complaint including 28 Alzheimer's disease (AD), 14 frontotemporal dementia (FTD), 17 vascular dementia (VD), 13 mild cognitive impairment (MCI), and 10 healthy persons. We discussed the difference of scores in different types of dementia. In the FAB, the scores of healthy persons and MCI were much higher compared with the scores of all types of dementia. There were high correlation between FAB and MMSE, Kana-hiroi test, and RCPM. Although some subjects showed normal score in MMSE and/or RCPM, they showed low score in FAB. Based on this, FAB is efficient for the differential diagnosis of dementia as brief screening tool.     

EFFECTIVENESS OF CYTODIAGNOSIS WITH PANCREATIC DUCT LAVAGE FLUID FOR PANCREATIC DUCTAL CARCINOMA: NEW SAMPLING TECHNIQUE

Background: Pancreatic carcinoma is one of the most lethal cancers. Because pancreatic carcinoma is still very difficult to diagnose in its early stage, many of these patients will be considered unsuitable for surgery. If a cytological diagnosis is obtained at initial endoscopic retrograde cholangiopancreatography (ERCP), suitable treatment will be initiated without delay. Methods: To increase the number of exfoliated cells from the pancreatic duct, we devised a new technique, pancreatic duct lavage fluid (PDLF), following bronchoalveolar lavage fluid. The present paper reports the effectiveness of cytological examination using PDLF in the diagnosis of pancreatic carcinoma. We examined 18 pancreatic carcinoma cases. After the endoscopic retrograde pancreatography (ERP), PDLF was collected from a double‐lumen catheter inserted into the main pancreatic duct. Saline injected from the lumen for the injection, and PDLF was aspirated from the other lumen for the guidewire at the same time. The cytological examination was performed using PDLF. Results: Exfoliated cells were more frequently found in PDLF from all patients. In 15 cases (83%), cytological examination of PDLF revealed positive cytological results as the diagnosis of pancreatic carcinoma. Conclusion: Cytological examination using PDLF has a high sensitivity for detection of pancreatic carcinoma. The new examination, PDLF, is simple, safe and effective, so we expect PDLF to become widely popular.     

Arrhythmogenic right ventricular dysplasia/cardiomyopathy assessed with 64-slice computed tomography

A 69-year-old man was admitted to hospital because of sustainedventricular tachycardia with right bundle branch block morphology.After abolition of ventricular tachycardia, an electrocardiogramshowed atrial fibrillation, complete right bundle     

CCR1 acts downstream of NFAT2 in osteoclastogenesis and enhances cell migration.

We found that a chemokine receptor gene, CCR1, acts downstream of NFAT2 in RANKL-stimulated RAW264 and bone marrow cells. The upstream regulatory region of CCR1 showed RANKL-dependent and CsA-suppressible promoter activity. Downregulation of the expression and function of CCR1 suppressed cell migration. INTRODUCTION: We previously reported that the expression of NFAT2 induced by RANKL is a key process for progression to multinucleated cells in an in vitro osteoclastogenesis system. Identifying the target genes of NFAT2 would thus be informative about the differentiation process. We focused here on chemokine and chemokine receptor genes that act downstream of NFAT2 in RAW264 cells as well as osteoclast precursors prepared from bone marrow cells. MATERIALS AND METHODS: RAW264 mouse monocyte/macrophage line cells were cultured with or without cyclosporin A (CsA) in the presence of RANKL or glutathione S-transferase (GST). Osteoclast precursors were prepared from bone marrow cells. RANKL-inducible and CsA-suppressible genes were searched for by microarray analysis, and expression was confirmed by quantitative RT-PCR. Promoter activity was measured by luciferase gene reporter assay. Short interfering (si)RNA for CCR1 was introduced in RAW264 cells. Cell migration activity was examined using a Boyden chamber assay. RESULTS AND CONCLUSIONS: We identified the chemokine receptor gene CCR1 as a gene showing significant differential expression profiles in osteoclastogenesis in the presence versus the absence of CsA, an inhibitor of NFAT. This property was unique to CCR1 among the chemokine and chemokine receptor genes examined in both RAW264 and bone marrow cells. The upstream regulatory region was isolated from CCR1, and its RANKL-dependent and CsA-suppressible promoter activity was confirmed. The functional significance of CCR1 was assessed by monitoring the migration of cells in a transwell migration assay, and this activity was abolished when either CsA- or CCR1 siRNA-treated cells were used. Moreover, treatment with a Galpha inhibitor pertussis toxin (PTX) or methiolynated-regulated on activation, normal T cells expressed and secreted (Met-RANTES), an antagonist of CCR1, suppressed multinucleated cell formation in the bone marrow cell system. Together, these results suggest that the CCR1 signaling cascade is under the control of NFAT2 and seems to enhance the migration of differentiating osteoclasts.     

Infantile subcortical leukohypodensity demonstrated by computed tomography

We reviewed the computed tomography scans of 126 term infants, ages 1-6 months; leukohypodensity was found just under the cerebral cortex (subcortical leukohypodensity [SLD]) in 3 infants (2.4%) at 1-3 months of age. On subsequent computed tomography at over 4 months of age, SLD had disappeared and anterior horn predominant dilatation of the lateral ventricles had appeared. Only 1 patient with a distinct SLD had a poor neurodevelopmental outcome: spastic diplegia. SLD in our patients is believed to be closely related to subcortical leukomalacia because of the similar location and age distribution. Transient SLD may be a mild form of cystic SLD which would require careful computed tomography follow-up examination in early infancy.