Analysis of hepatitis B surface antigen mutations in Mongolia: molecular epidemiology and implications for mass vaccination

Although the potential significance of hepatitis B surface antigen (HBsAg) mutants for failure of immunization has been studied in some endemic countries, whether the "a" determinant variants are responsible for vaccine failure in Mongolia remains unknown. Fifty-nine HBsAg-positive children (age: 8.8 +/- 0.9 years) who had been observed during the nationwide survey of vaccinated cohorts conducted in 2004 were subjected to molecular analyses of hepatitis B virus (HBV). Partial S gene sequences encoding amino acids (aa) 40-171 of HBsAg were determined in 57 children (96.6%) who had detectable HBV DNA. Phylogenetic analysis of the S gene sequences revealed that genotype D accounted for 93.0% and genotype A for 5.3%. Only one child (1.7%) had HBVs of genotypes A and D. HBsAg mutations were found in 17 (29.8%) children ranging from 1 to 4 aa per subject (mean +/- SD, 1.6 +/- 0.9 aa). Pro127Thr and Thr118Ala were the most common substitutions, which occurred in 6 (10.5%) and 3 (5.3%) subjects, respectively; none had Gly145Arg. There were no significant associations in the prevalence of HBsAg mutations with age, sex, residential area, or vaccination status against hepatitis B. Analysis of the deduced amino acid sequence of the entire preS1/preS2/S gene revealed that eight genotype D isolates and one genotype A isolate were quite similar to previously-reported wild-type isolates, suggesting that they are essentially wild-type, but not vaccine-induced mutants. In conclusion, the results demonstrate that hepatitis B surface gene mutants do not play a significant role in vaccination failure in Mongolia.

Dental hygiene education in Japan: present status and future directions

The aim of this report is to provide basic information about the historical development, current status and future needs of education and training of dental hygienists in Japan. The first formal training of dental hygienists in Japan started at Tokyo in 1949. Restructure and modification of the dental hygiene education system has been reiterated over the years in order to satisfy the needs of the constantly changing society. Although previously only vocational training was provided for dental hygienists, higher-level education has been conducted. The present legislation of dental hygiene has gone through a complicated process. The student should take the dental hygienist licensing examination which is held once a year by the National Board organized by the Ministry of Health, Labour and Welfare. Currently there are 136 dental hygiene schools and the total enrolment is about 7000. The duration of dental hygiene education course has been prolonged from 2 to 3 years since 2001. In 2004, the 4-year course started. The 2-year dental hygiene education program is expected to be replaced with the 3- and 4-year courses by 2010. The dental hygiene education system in Japan will be improved in many ways as dental hygienists are expected to participate in health promotion and preventive care, and to gain knowledge of the economics and organization of health care in relation to oral hygiene.

Intrapatellar tendon lipoma with chondro-osseous differentiation: detection of HMGA2-LPP fusion gene transcript

A 54 year old man developed an unusual lipoma in the patellar tendon, consisting of a fibro-adipose component and a chondro-osseous component. The fibro-adipose component contained mature adipocytes, lipoblasts, and fibroblasts; the chondro-osseous component showed typical endochondral bone formation. Molecular analysis showed that the identical HMGA2-LPP fusion transcript-characteristic of lipoma, parosteal lipoma, and pulmonary chondroid hamartoma-was detectable in the both components.

Demonstration of Inter- and Intracellular Distribution of Boron and Gadolinium Using Micro-Proton-Induced X-Ray Emission (Micro-PIXE)

Micro-proton-induced X-ray emission (Micro-PIXE) was applied to determine inter- and intracellular distribution of boron (10B) and gadolinium (157Gd), the capture atoms used to kill tumor cells in neutron capture therapy (NCT). Cultured 9L gliosarcoma cells on Mylar film were exposed to sodium borocaptate (BSH) and gadobenate dimeglumine (Gd-BOPTA). To analyze the inter- and intracellular distribution of 10B and 157Gd in 9L gliosarcoma cells, the cells were irradiated using a proton beam of 1.7 or 3 MeV energy collimated to 1 microm diameter and emission X-ray was detected. The distribution of 10B and 157Gd in 9L gliosarcoma cells was then examined. In this study, we could directly analyze the inter- and intracellular distribution of 10B and 157Gd elements in 9L gliosarcoma cells directly using Micro-PIXE. This is the first report on the distribution of 10B employing a method to detect gamma-rays resulting from the nuclear reaction of 10B using particle-induced gamma-ray emission (PIGE). These results show that the distribution of 157Gd elements was correctly measured using micro-PIXE. 157Gd should have the same tendency as 10B in cultured 9L gliosarcoma cells and agree with the distribution in 9L gliosarcoma cells. Further investigation is necessary for a higher spatial resolution and optimization of the measurement time or improvement of the sampling method. In the future, it will be possible to employ this method to analyze the intracellular microdistribution of the capture element and in the development of new drugs for NCT.

A case of esophageal small cell carcinoma with multiple liver metastases responding to chemotherapy with irinotecan plus cisplatin

We report a case of small cell esophageal carcinoma (SCEC) with multiple liver metastases treated with some success by chemotherapy with irinotecan (CPT-11) plus cisplatin (CDDP). Radiologic and endoscopic examination of a 75-year-old man with multiple liver tumors disclosed a 4.0-cm type 2 tumor in the middle third of the esophagus. An endoscopically obtained biopsy specimen was diagnosed as undifferentiated small cell carcinoma. Multiple liver metastases were confirmed but lymph node metastases and distant metastases other than those in the liver were not detected. After six courses of chemotherapy with CPT-11 plus CDDP, the primary lesion showed complete response and liver metastases showed partial response. However, because all lesions almost immediately relapsed or progressed, arterial infusion chemotherapy for liver metastases and radiation for the primary lesion were given as second-line treatment. The primary lesion showed complete response with radiation. Arterial infusion chemotherapy prevented the progression of liver metastases once, but the patient died of liver failure at last. No distant lesions including metastatic lymph nodes were confirmed over the course of his illness, and the patient survived for a year after first diagnosis. Although the prognosis of SCEC is quite unfavorable due to highly aggressive behavior, a better prognosis is possible with effective chemotherapy and second-line treatment is important in improving prognosis.

[Clinical experience of sivelestat sodium hydrate for severe reexpansion pulmonary edema; report of a case]

An 81-year-old man was referred to our hospital for the treatment for left spontaneous pneumothorax. A chest X-ray revealed a left-sided total pneumothorax and complete collapse of the lung. After intravenous administration of methylprednisolone, a 16 Fr chest tube was inserted, and drainage was started without negative pressure suction. Four hours after chest tube insertion, the patient's condition deteriorated. He complained severe cough and dyspnea, and pulse oximetry reading was 70%. A repeat chest X-ray demonstrated diffuse reexpansion pulmonary edema (RPE) on the left. After mechanical ventilation and intravenous infusion therapy with sivelestat sodium hydrate, methylprednisolone and ulinastatin were started, P(O2)/ Fi(O2) ratio improved rapidly. He was extubated on hospital day 6 and was discharged after pleurodesis for the pneumothorax. This case suggests that sivelestat sodium hydrate may be useful for the treatment for RPE.

HPA axis normalization, estimated by DEX/CRH test, but less alteration on cerebral glucose metabolism in depressed patients receiving ECT after medication treatment failures

OBJECTIVE

To examine the clinical effects of electroconvulsive therapy (ECT) on depressed patients with medication treatment failures, we investigated the alterations in hypothalamic-pituitary-adrenocortical (HPA) function and regional cerebral metabolism rate of glucose (rCMRGlu) after ECT in these patients.

METHOD

Before and after ECT, the combined dexamethasone/corticotrophin-releasing hormone (DEX/CRH) test was administered to seven patients who were referred for ECT. In the same patients, (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) was also assessed.

RESULTS

Cortisol response in the DEX/CRH test significantly decreased after a successful ECT. A significant hypometabolism in various frontal regions and hypermetabolism in the parietal regions of these patients when compared with controls remained after ECT.

CONCLUSION

Depressed patients who failed trials of antidepressant medication showed a remission with ECT that was accompanied by resolution of HPA dysregulation. However, measures of cerebral brain metabolism did not resolve.

Surgical relief of causalgia with an artificial nerve guide tube: Successful surgical treatment of causalgia (Complex Regional Pain Syndrome Type II) by in situ tissue engineering with a polyglycolic acid-collagen tube

Two patients with causalgia associated with allodynia and finger contracture were treated surgically with a bioresorbable nerve guide tube made from polygycolic acid and collagen: the injured segment of the digital nerve was resected and the resulting gap (25 and 36mm) was bridged with the tube. In both cases, a neuroma was found on the injured nerve and many sprouting branches were. After reconstruction, the causalgia and allodynia disappeared and movement of the fingers recovered during the following 6 months. Functional recovery was objectively identified for 1 year and 9 months. Both patients regained full use of their finger and were free of discomfort for up to 24 and 18 months, respectively. Since the first description of causalgia in 1864, there has been no definitive treatment for this intractable burning pain. Our experience shows that at least some types of causalgia can be resolved successfully by surgery.

Development of a novel, multi-analyte biosensor system for assaying cell division: identification of cell proliferation/death precursor events

A novel, miniaturized biosensor system was created by combining the electrophysiological response of immobilized cells with superoxide-sensing technology, optical and fluorescence microscopy. Vero cells were immobilized in a calcium alginate matrix (at a density of 1.7 x 10(6) cells ml(-1)). A 0.5 cm x 0.5 cm piece of cell-containing gel matrix was aseptically adhered on a glass microscope slide with a microfabricated gold electrode array, sealed with a cover slip and provided with Dulbecco's medium +10% (v/v) fetal calf serum every day by means of a capillary feeding tube. During a culture period of 7 days, the membrane potential of immobilized cells was continuously monitored, while cell division was assayed with an optical microscope. In addition, daily measurements of immobilized cell membrane potential, viability, RNA and calcium concentration, radical oxygen species (ROS) and glutathione accumulation, were conducted by fluorescence microscopy after provision of an appropriate dye. Superoxide accumulation was assayed by covering the electrodes with superoxide dismutase (SOD). Maximum cell membrane potential values and superoxide production were observed upon initiation of cell division. Using the novel biosensor, we were able to correlate seven different cell physiological parameters to each other and formulate a model for ROS-mediated signaling function on cell division and death. In addition, we were able to predict cell proliferation or death by comparing the relative response of the electrophysiological and superoxide sensor during the culture period.

New canine spinal cord injury model free from laminectomy

The present report details the successful development of a model for spinal cord injury (SCI). This model is simple, reproducible, and requires no laminectomy. Development of the model was carried out using fourteen dogs. A balloon catheter was inserted into the extradural space via the intervertebral foramen of each dog, then the balloon was inflated at the L1 level by injection of saline. Six dogs underwent compression with a balloon volume of 1.5 ml, three dogs with a volume of 1.0 ml, and the remaining five dogs were used as uninjured controls. We applied the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale to the dogs. Compression of the spinal cord for 10 min at 1.5 ml produced severe paraplegia (BBB remained zero or one for 6 months following surgery), while compression for the same time interval at 1.0 ml produced moderate paraplegia. Electrophysiological tests showed no hindlimb movement upon stimulation cranial to the site of injury in the 1.5-ml group. The volume of abnormal-intensity lesions in the 1.0-ml group calculated using MR imaging showed no marked changes in either high- or low-intensity lesions after 3 months, whereas in the 1.5-ml group, the low-intensity lesions alone showed a marked increase. Pathological examination of the damaged spinal cord showed the formation of cavities surrounded by scar tissue containing high levels of collagen. These findings closely resembled those of clinical cases. It was concluded that 10 min of balloon compression with a volume of 1.5 ml caused irreversible paraplegia in dogs.

Morphological imaging in the localization of neuroendocrine gastroenteropancreatic tumors found by somatostatin receptor scintigraphy

PURPOSE

To evaluate the necessity of morphological images (MI) in reading somatostatin receptor scintigraphy (SRS) in patients with suspected neuroendocrine gastroenteropancreatic (GEP) tumors.

MATERIAL AND METHODS

A Japanese multicenter clinical trial of SRS was conducted in 40 patients with suspected GEP tumors. Three experienced radiologists interpreted the images in three separate sessions in a blinded manner (1: SRS images alone, 2: MI alone, 3: SRS and MI analyzed simultaneously), and the reading results of each session were compared. In addition, the diagnostic abilities of SRS, MI and SRS alone and simultaneous SRS and MI readings were compared for patients where final diagnosis was obtained.

RESULTS

SRS detected more suspected lesions (positive or inconclusive uptake) than morphological images did (51 vs 27 lesions), but included many physiological uptakes detected as positive or inconclusive uptakes. Combined reading of SRS and morphological images helped to correctly recognize these physiological uptakes, and also helped in determining the anatomical localization of the abnormal uptakes. Combined reading of SRS and morphological images gave the highest diagnostic impact.

CONCLUSION

The sensitivity of SRS with regard to GEP is high. However the specificity is very low. Morphologic imaging is necessary for the exclusion of physiological uptake and correct anatomic location of an abnormal tracer uptake. The combined reading of SRS and morphologic imaging studies gives the highest diagnostic impact.

Combination of boron and gadolinium compounds for neutron capture therapy. An in vitro study

In neutron capture therapy, the therapeutic effect of the boron compound is based on alpha particles produced by the B(n, alpha) reaction while with the gadolinium compound the main radiation effect is from gamma rays derived from the Gd(n, gamma) reaction. The uptake and distribution within the tumor may be different among these compounds. Thus, the combination of the boron and gadolinium compounds may be beneficial for enhancing the radiation dose to the tumor. Chinese hamster fibroblast V79 cells were used. For the neutron targeting compounds, 10B (BSH) at 0, 5, 10, and 15 ppm, and 157Gd (Gd-BOPTA) at 0, 800, 1600, 2400, 3200, and 4800 ppm, were combined. The neutron irradiation was performed with thermal neutrons for 30 min. (neutron flux: 0.84 x 10(8) n/cm2/s in free air). The combination of the boron and gadolinium compounds showed an additive effect when the gadolinium concentration was lower than 1600 ppm. This additive effect decreased as a function of gadolinium concentration at 2400 ppm and resulted in no additive effect at more than 3200 ppm of gadolinium. In conclusion, the combination of the boron and gadolinium compounds can enhance the therapeutic effect with an optimum concentration ratio. When the gadolinium concentration is too high, it may weaken the boron neutron capture reaction due to the high cross-section of gadolinium compound against neutrons.

The influence of GoldbonderTM and pre-heat treatment on the adhesion of titanium alloy and porcelain

The present study examines the influence of a goldbonder and pre-heat treatment of the titanium on the adhesion of porcelain. Three groups of titanium substrates were given various heat treatments, namely; none, 200 degrees and 600 degrees C, respectively before applying goldbonder. The surfaces of the titanium specimens following heat treatment were examined with an electron spectroscopy for chemical analysis (ESCA). The adhesion strength was measured by the strain energy release rate (G), which was proposed by Suansuwan N and Swain MV (Int J Prosthodont. 1999;12:547). After bonding porcelain onto titanium substrates with the aid of the goldbonder, the porcelain side of specimens was notched to the interface with a thin diamond saw. Then the samples were subject to a four-point bending test. Following fracture testing, specimens were examined with a scanning electron microscope (SEM) and SEM with energy-dispersive spectroscopic analysis (EDS). The mean G-values were 38.87, 28.64 and 16.33 J m(-2), respectively. ESCA analysis showed the composition of aluminium of the surface of 600 degrees C pre-heat treatment became richer than that of the others. SEM images of the fracture surfaces showed that for the 600 degrees C pre-heat treatment fracture occurred within the oxidation layer on the titanium. High temperature pre-heat treatment prior to bonding significantly reduces porcelain bonded to titanium with the goldbonder. The Influence of Goldbonder and Pre-heat Treatment on the Adhesion of Titanium Alloy and Porcelain.

Experimental study on the regeneration of peripheral nerve gaps through a polyglycolic acid-collagen (PGA-collagen) tube

We have developed a bioabsorbable polyglycolic acid (PGA) tube filled with collagen sponge (PGA-collagen tube) as a nerve connective guide, and compared its effectiveness with that of autograft in terms of nerve regeneration across a gap. The PGA-collagen tube was implanted into 24 beagle dogs across a 15-mm gap in the left peroneal nerve. The right peroneal nerve was reconstructed with the autograft harvested from the left side, as a control. After the surgery, the connective tissue extended from both cut ends in the PGA-collagen tube and connected again at the center. Pathologically, the collagen sponge in the tube provided adequate scaffolding for nerve tissue extension, and the nerve tissue reconnected within 3 weeks. Electrophysiologically, muscle-evoked potentials (MEPs) and compound nerve action potentials (CNAPs) were detected 18 days after the surgery. For up to 6 months postsurgery, CNAPs and somatosensory-evoked potentials (SEPs) on the PGA-collagen side had a shorter latency and larger peak voltage than those on the autograft side. The myelinated axons on the PGA side were larger in diameter than those on the autograft side. It is suggested that the PGA-collagen tube has the potential to be an effective alternative to conventional autografting for the repair of some peripheral nerve defects.

Current clinical results of the Tsukuba BNCT trial

Nine high grade gliomas (5 glioblastomas and 4 anaplastic astrocytomas) were treated with BSH-based intaoperative boron neutron capture therapy (IOBNCT). BSH (100 mg/kg body weight) was intravenously injected, followed by single fraction irradiation using the mixed thermal/epithermal beam of Japan Research Reactor 4. The blood boron level at the time of irradiation averaged 29.9 (18.8-39.5)microg/g. The peak thermal neutron flux as determined by post-irradiation measurements varied from 1.99 to 2.77x10(9) n cm(-2)s(-1). No serious BSH-related toxicity was observed in this series. The interim survival data in this study showed median survival times of 23.2 months for glioblastoma and 25.9 months for anaplastic astrocytoma, results which are consistent with the current conventional radiotherapy with/without boost radiation. Of the 4 residual tumors, 2 showed complete response (CR) and 2 showed partial response (PR) within 6 months following BNCT. No linear correlation was proved between the dose and the occurrence of early neurological events. The maximum boron dose of 11.7-12.2 Gy in the brain related to the occurrence of radiation necrosis. The clinical application of a mixed thermal/epithermal beam and JRR-4 facilities on BSH-based IOBNCT proved to be safe and effective in this series.

A case of severe low back pain associated with Richard disease (lumbosacral transitional vertebra)

The imaging findings in some cases of low back pain are difficult to describe and the pathophysiology is not clear because subjective findings are usually difficult to document. This report concerns a rare case about the lumbosacral joint causing persistent severe back pain which in itself does not usually have any pathological meaning. We describe the diagnosis, treatment, and outcome of a patient suffering from low back pain with lumbosacral transitional vertebra. The radiological examination showed the congenitally malformed transverse processes of the 5th lumbar vertebra to create a facet joint-like shape at the sacral ala region on both sides. Surgery resulted in immediate disappearance of the low back pain. When the lumbosacral junction shows some instability without fusion, the joint-like region could be the cause of low back pain. The lumbosacral transitional vertebra may be associated with low back pain. Electric denervation of the space between the transverse process of 5th lumbar vertebra and sacral ala is minimally invasive and effective for pain eradication.

Management of Tight Filum Terminale

OBJECTIVE

Tight filum terminale (TFT) is not an uncommon condition, but due to insufficient diagnostic options this syndrome is often overlooked and left untreated. The present study was designed to investigate surgical results concerning neurological perspectives and diagnostic methods for TFT.

METHODS

Subjects for this study consisted of 37 patients with TFT who were surgically treated by transecting the filum terminale. We examined the surgical outcomes with regard to low back pain, leg pain, and bladder and bowel dysfunctions, and analyzed neurological and imaging findings.

RESULTS

TFT diagnosis was based on the following five criteria; 1) low back pain, 2) non-dermatomal leg pain, 3) bladder-bowel dysfunction, 4) spinal stiffness, and 5) a newly developed positive provocation test for spinal cord extension.

CONCLUSION

The survey of surgical outcomes indicated that satisfactory results could be obtained by surgical release of the filum terminale, while neural function was still reversible. In particular, our newly devised provocation test was shown to be highly effective for the early diagnosis of this disorder.

The effects of frequency-encoding gradient upon detectability of the margins and height measurements of normal adult pituitary glands

We investigated the effects of frequency-encoding gradient (FEG) upon detectability and height measurements of the normal adult pituitary gland. We obtained two sets of T1-weighted sagittal images of the pituitary gland from 70 adult subjects without known pituitary dysfunction using 1.5 tesla imagers; one with an inferior-superior FEG, and one with an anterior-posterior FEG. We classified the subjects into three types according to the distribution of fatty marrow in the clivus. Each set of images was assessed for pituitary height on midline sagittal images, and detectability of pituitary margins. Height measurements and detectability scores were evaluated for significant difference between the two FEGs. In subjects with fatty marrow in the clivus, there was significant difference between pituitary height measurements (P < 0.005) and pituitary margin detectability (P < 0.001). Care should be taken to image the pituitary gland using an anterior-posterior FEG.