Imaging features contributing to the diagnosis of ameloblastomas and keratocystic odontogenic tumours: logistic regression analysis.

OBJECTIVE: The aim of this study was to clarify the characteristic imaging features that can be used to differentiate ameloblastomas from keratocystic odontogenic tumours and to examine the significant imaging features contributing to a correct diagnosis. METHODS: 60 observers (39 specialists in oral and maxillofacial radiology and 21 non-specialists) examined CT and/or panoramic images of 10 ameloblastomas and 10 keratocystic odontogenic tumours shown on a webpage and made diagnoses. Their correct answer ratios were then calculated. The imaging features of the tumours were evaluated and expressed as binary numbers or quantitative values. The imaging features that contributed to a correct diagnosis were elucidated using logistic regression analysis. RESULTS: The mean correct answer ratio was 61.3% ± 17.2% for the diagnosis of ameloblastomas and keratocystic odontogenic tumours. CT images produced higher correct answer ratios for diagnosis of keratocystic odontogenic tumours by specialists. The significantly different imaging features between ameloblastomas and keratocystic odontogenic tumours were the degree of bone expansion and the presence of high-density areas. The significant imaging features contributing to a correct imaging diagnosis were the number of locules, the presence of high-density areas and the inclusion of impacted teeth. CONCLUSION: The presence of high-density areas is the most useful feature in the differential diagnosis of ameloblastomas and keratocystic odontogenic tumours based on comparison of the imaging features of both tumours and examination of the diagnostic contributions of these features.

Use of sonographic elastography of the masseter muscles for optimizing massage pressure: a preliminary study.

To examine the stiffness of the masseter muscle using sonographic elastography and to investigate its relationship with the most comfortable massage pressure in the healthy volunteers. In 16 healthy volunteers (10 men and 6 women), the Masseter Stiffness Index (MSI) was measured using EUB-7000 real-time tissue elastography. They underwent massages at three kinds of pressures using the Oral Rehabilitation Robot (WAO-1). A subjective evaluation regarding the comfort of each massage was recorded on the visual analogue scale. Elastography was also performed in two patients with temporomandibular joint dysfunction with the myofascial pain. The mean MSI of the right and left muscles in the healthy volunteers were 0.85 +/- 0.44 and 0.74 +/- 0.35 respectively. There was no significant difference between the right and left MSI in the healthy volunteers. The MSI was related to massage pressure at which the healthy men felt most comfortable. The two temporomandibular disorder patients had a large laterality in the MSI. The MSI was related to the most comfortable massage pressure in the healthy men. The MSI can be one index for determining the massage pressure.

Positional changes of oropharyngeal structures due to gravity in the upright and supine positions.

OBJECTIVES: To compare the responses of oropharyngeal structures to gravity while sitting upright or lying down in a supine position. METHODS: Seven subjects were evaluated by cone beam CT (CBCT) while in the upright position and by a four-row multidetector helical CT (MDCT) while in the supine position. All of the voxel sizes were adjusted to be 0.3x0.3x0.3 mm3 in the x-y-z axis. The posterior nasal spine, basion and fourth cervical bone were used as references to measure positional changes in the oropharyngeal structures between the upright and supine positions. The smallest areas in the oropharynx were also evaluated. RESULTS: The soft palate, epiglottis and entrance of the oesophagus moved caudally with the positional change from supine to sitting upright, and moved posteriorly when the position changed from an upright to a supine position. The hyoid bone moved caudally but not posteriorly in response to the same positional changes. The width and length of the smallest area present in the oropharynx was larger in the upright position than in the supine position. CONCLUSIONS: Gravity can produce movements in oropharyngeal structures in response to postural changes between sitting upright and lying in the supine position.

Training in Neurovascular Intervention Usefulness of in-Vitro Model and Clinical Practice.

SUMMARY: We introduce our training tools and system of neurovascular intervention. An in vitro cerebral vascular model was used for the young residents to understand the basic interventional techniques and devices. The model included several vascular lesions such as cerebral aneurysm, dural arterio-venous fistula, or carotid artery stenosis. Endovascular procedures in the model were performed under fluoroscopic or direct visual control, and consecutive haemodynamic changes were visualized by using digital subtraction angiography and direct observation. Thus, traineess could have an easy understanding of clinical conditions. New medical devices, such as platinum coils, were successfully implanted in the model under stable conditions. After the initial training using vascular model, the residents had started clinical experiences under the control of senior surgeons. Although it is difficult to describe usefulness of our clinical training, we believe that we provide enough good quality and quantity of clinical cases to the residents. Because our endovascular team has recently had150-200 interventional procedures every year, one resident can have experienced more than 100 cases per year. The qualification of a Board Certified Specialist of the Japanese Society of Intravascular Neurosurgery (JSIN) requires that the applicant must have experienced more than 100 cases for four years. So our residents can have enough case materials to qualify the board examination.

Molecular cloning and expression of the cDNA encoding feline granulocyte colony-stimulating factor.

Both genomic DNA and cDNA of the feline granulocyte colony-stimulating factor (G-CSF) gene were cloned from CRFK cells. Southern blot analysis showed that the haploid genome contains a single copy of the G-CSF gene. The RT-PCR analysis of several feline cell lines revealed expression of G-CSF mRNA in response to lipopolysaccharide stimulation. Sequence analysis of genomic and cDNA clones indicated that the intron-exon junction structure is conserved between the human and the feline G-CSF genes. The G-CSF coding region encodes a predicted protein of 195 amino acids including a signal sequence of 21 amino acids. The feline G-CSF amino acid sequence shares a high degree of identity with the canine (90.8%), human (87.4%), ovine (83.9%), bovine (82.8%), porcine (80.5%), murine (70.7%) and rat (66.8%) G-CSF. The feline G-CSF expressed in insect cells using recombinant baculovirus vector was biologically active as measured in a proliferation assay using NFS-60 cells and an induction assay of leukocytes in cats.

[Usefulness of a new mechanical detachable coil for neurovascular intervention].

The electrolytically detachable platinum coil (Guglielmi Detachable Coil: GDC) is a safe and efficient endovascular tool for treatment of cerebral aneurysms. However, the GDC still has some problems, including a prolonged detaching time and high cost. The Detach Coil System (DCS) is a newly developed platinum detachable coil for the treatment of neurovascular diseases. This has a mechanical "screw" detachment system, which can be detached faster than the GDC. The platinum coil is mounted to the tip of the delivery wire by the "screw" system. For detaching the coil, 20-25 times anti-clockwise rotation of the delivery wire using a "detach locking device" is required. We report our preliminary clinical experience of using the DCS in 11 patients. This series included 5 sacral aneurysms, 3 dissecting aneurysms, and 3 dural arteriovenous fistulas. Seventy-five coils were used in total, of which 5 coils were retrieved and 70 coils were implanted. The detaching time of each DCS was 15-20 seconds, which was much faster than that of the GDC. All lesions were successfully treated without symptomatic complications. In the limited number of cases, our result suggest that the DCS allowed safe and fast endovascular treatment of neurovascular disease at a lower cost.

[Use of the GDC for embolization of a tumor fed by a cavernous branch of the internal carotid artery].

Currently, embolization of small branches of the internal carotid artery (ICA) can be embolized through superselective microcatheterization, followed by the injection of liquid or particulate embolic materials. Often, however, a microcatheter cannot be placed in a stable enough position to allow an endovascular surgeon to perform a safe embolization, and the reflux of embolic agents into the main trunk of the ICA is a major concern. Meticulous technique and a detailed knowledge of the vascular anatomy of the cavernous sinus region are necessary to maximize devascularization of the lesion and to minimize the risk of complications. This report describes the case of a patient with a hypervascular tumor whose feeding vessel from the cavernous ICA was successfully occluded with polyvinyl alcohol (PVA) combined with a regular Guglielmi detachable coil (GDC). A 62-year-old woman had a left-sided petroclival meningioma, which was diagnosed based on computed tomography and magnetic resonance studies. Transfemoral angiographic studies demonstrated that the tumor was fed by intracavernous branches of the left ICA. We believed that another embolic agent would have presented a risk of reflux into the ICA, with possible unwanted occlusion of normal intracranial arteries. A single GDC was sufficient to occlude the feeding artery, and the patient underwent successful surgery 3 days after the endovascular procedure. The GDC can eliminate the ICA supply to hypervascular tumors safely when liquid or particle embolic materials would present a risk of reflux into normal arteries. This device can be positioned and repositioned and can be detached without mechanical force. It may also decrease the risk of unwanted embolization of normal intracranial arteries.

Expression of canine interferon-gamma by a recombinant vaccinia virus and its antiviral effect.

A recombinant vaccinia virus-expressing canine interferon (IFN)-gamma (vv/cIFN-gamma) was constructed. In rabbit kidney (RK13) and canine A72 cells infected with vv/cIFN-gamma, IFN activity was detected in the culture supernatants of both cell types. Canine IFN-gamma was also detected in both cell extracts by Western blot. The activity of the recombinant canine IFN-gamma in RK13 cells was higher than that in A72 cells. The vv/cIFN-gamma could not grow in A72 cells at a low multiplicity of infection, probably due to the antiviral activity of the canine IFN-gamma produced. Although exogenous IFN-gamma did not inhibit the growth of vaccinia virus, addition of anti-canine IFN-gamma serum recovered the growth of the vv/cIFN-gamma on A72 cells in a dose-dependent manner. These results suggest that the growth of vv/cIFN-gamma was inhibited by IFN-gamma produced in a paracrine and autocrine manner. In addition, the recombinant canine IFN-gamma inhibited the multiplication of canine herpesvirus, pseudorabies virus and canine adenovirus type 1 in Madin-Darby canine kidney cells. The antiviral effect of canine IFN-gamma was more effective than that of canine IFN-beta. From the present studies, we concluded the recombinant virus may be a useful suicide viral vector.

The importance of venous hypertension in the formation of dural arteriovenous fistulas: a case report of multiple fistulas remote from sinus thrombosis.

Various hypotheses have been reported concerning the pathogenesis of dural arteriovenous fistulas (DAVFs). However, it is still controversial whether sinus thrombosis or venous hypertension has a greater influence on the formation of DAVFs. We present a rare case of multiple DAVFs that developed after sinus thrombosis. Chronic venous hypertension secondary to sinus thrombosis in the left transverse-sigmoid sinus induced the multiple DAVFs, including one in the right cavernous sinus, which was remote from the occluded sinus. This case indicates the importance of venous hypertension in the formation of DAVFs.

Biological and immunogenic properties of rabies virus glycoprotein expressed by canine herpesvirus vector.

In order to evaluate whether canine herpesvirus (CHV) could be used as a live vector for the expression of heterologous immunogenes, we constructed a recombinant canine herpesvirus (CHV) expressing glycoprotein (G protein) of rabies virus (RV). The gene of G protein was inserted within the thymidine kinase gene of CHV YP11mu strain under the control of the human cytomegalovirus immediate early promoter. The G protein expressed by the recombinant CHV was processed and transported to the cell surface as in RV infected cells, and showed the same biological activities such as low pH dependent cell fusion and hemadsorption. The antigenic authenticity of the recombinant G protein was confirmed by a panel of monoclonal antibodies specific for G protein. Dogs inoculated intransally with the recombinant CHV produced higher titres of virus neutralizing antibodies against RV than those inoculated with a commercial, inactivated rabies vaccine. These results suggest that the CHV recombinant expressing G protein can be used as a vaccine to control canine rabies and that CHV may be useful as a vector to develop live recombinant against other infectious diseases in dogs.

Cis-acting elements in the lytic origin of DNA replication of Marek's disease virus type 1.

The replication origin of Marek's disease virus (MDV) type 1 was analysed by using a transient replication assay with plasmids containing various fragments of MDV strain Md5 genomic DNA. Plasmid pMBH, containing the BamHI-H fragment, showed replication activity in MDV-infected chicken embryonic fibroblasts (CEF). By deletion analysis of pMBH, two regions, the promoter-enhancer region of the MDV pp38 gene and the 132 bp tandem direct repeat, were shown to be required for replication activity. Replication of pMBH was not observed in uninfected CEF, suggesting that a trans-acting factor(s) encoded by the MDV genome was necessary for replication.

Cloning and expression of the canine interferon-beta gene.

We isolated the canine interferon-beta (IFN-beta) gene from dog liver chromosomal DNA by the polymerase chain reaction (PCR). The coding region encodes a predicted protein of 197 amino acids, consisting of a signal sequence of 32 amino acids and a mature IFN-beta of 165 amino acids. In the IFN-beta sequence, there are five potential N-glycosylation sites and four cysteine residues. Canine IFN-beta has 44% and 60% amino acid sequence homology with murine and human IFN-beta, respectively, whereas it has only 28% homology with canine IFN-alpha. The canine IFN-beta gene was expressed in insect cells under the control of the polyhedrin promoter in a recombinant baculovirus. After infecting Sf21 cells with the recombinant baculovirus, IFN activity was detected in the culture medium, indicating that it is secreted from the cells. This activity was stable from pH 2 to 12 for 18 h at 4 degrees C. Southern blot analysis indicated that the gene for canine IFN-beta is a single gene in the dog haploid chromosome.

Synthesis of alpha-L-mannopyranosyl-containing disaccharides and phenols as substrates for the alpha-L-mannosidase activity of commercial naringinase.

In order to clarify the substrate specificity of the alpha-L-mannosidase activity of naringinase (Sigma), the following disaccharides and phenol glycosides were freshly prepared: methyl 2-O-(alpha-L-mannopyranosyl)-beta-D-glucoside (1), methyl 3-O-(alpha-L-mannopyranosyl)-alpha-D-glucoside (2), methyl 4-O-(alpha-L-mannopyranosyl)-alpha-D-glucoside (3), methyl 5-O-(alpha-L-mannopyranosyl)-beta-D-glucoside (4), methyl 6-O-(alpha-L-mannopyranosyl)-alpha-D-glucoside (5), 6-O-(alpha-L-mannopyranosyl)-D-galactose (6), p-nitrophenyl alpha-L-mannoside (7), and 4-methyl umbelliferone alpha-L-mannoside (8). These compounds, except for 3 and 5 were hydrolyzed with naringinase.

Tissue-specific expression of two isoforms of chicken fibroblast growth factor receptor, bek and Cek3.

Chicken bek and Cek3 are isoforms of the fibroblast growth factor receptor which consist of primary structures that are identical except for a variation within the last of three immunoglobulin-like repeats in the ligand-binding domain. Northern blot analysis using isoform-specific probes revealed that the bek mRNA is expressed exclusively in lung, whereas the Cek3 mRNA is expressed prominently in brain and weakly in lung. We further localized these transcripts in brain and lung by in situ hybridization histochemistry. In lung, the expression of the bek and Cek3 transcripts was distinguished in the smooth muscle of the parabronchus and in the arterial adventitia. On the other hand, in brain, the Cek3 transcript was detected in three areas: the corpus medullare of the metencephalon (cerebellum), the archiastriatum of the telencephalon, and the ependymal cells of the ventriculare of the mesencephalon. Two putative exons corresponding to isoform-specific sequences, respectively, were found to be closely located on the chicken genome. These results indicate that bek/Cek3 isoforms are derived from the same premessenger and that their expression is regulated in a tissue- or even area-specific manner. Moreover, another potential isoform produced by a new splice site within the Cek3-specific exon has been isolated.