Nonreciprocal Phonon Propagation in a Metallic Chiral Magnet

The phonon magnetochiral effect (MChE) is the nonreciprocal acoustic and thermal transports of phonons caused by the simultaneous breaking of the mirror and time-reversal symmetries. So far, the phonon MChE has been observed only in a ferrimagnetic insulator Cu_{2}OSeO_{3}, where the nonreciprocal response disappears above the Curie temperature of 58 K. Here, we study the nonreciprocal acoustic properties of a room-temperature ferromagnet Co_{9}Zn_{9}Mn_{2} for unveiling the phonon MChE close to room temperature. Surprisingly, the nonreciprocity in this metallic compound is enhanced at higher temperatures and observed up to 250 K. This clear contrast between insulating Cu_{2}OSeO_{3} and metallic Co_{9}Zn_{9}Mn_{2} suggests that metallic magnets have a mechanism to enhance the nonreciprocity at higher temperatures. From the ultrasound and microwave-spectroscopy experiments, we conclude that the magnitude of the phonon MChE of Co_{9}Zn_{9}Mn_{2} mostly depends on the Gilbert damping, which increases at low temperatures and hinders the magnon-phonon hybridization. Our results suggest that the phonon nonreciprocity could be further enhanced by engineering the magnon band of materials.

Direct visualization of the three-dimensional shape of skyrmion strings in a noncentrosymmetric magnet

Magnetic skyrmions are topologically stable swirling spin textures that appear as particle-like objects in two-dimensional (2D) systems. Here, utilizing scalar magnetic X-ray tomography under applied magnetic fields, we report the direct visualization of the three-dimensional (3D) shape of individual skyrmion strings in the room-temperature skyrmion-hosting non-centrosymmetric compound Mn_1.4Pt_0.9Pd_0.1Sn. Through the tomographic reconstruction of the 3D distribution of the [001] magnetization component on the basis of transmission images taken at various angles, we identify a skyrmion string running through the entire thickness of the sample, as well as various defect structures, such as the interrupted and Y-shaped strings. The observed point defect may represent the Bloch point serving as an emergent magnetic monopole, as proposed theoretically. Our tomographic approach with a tunable magnetic field paves the way for direct visualization of the structural dynamics of individual skyrmion strings in 3D space, which will contribute to a better understanding of the creation, annihilation and transfer of these topological objects.

Single Cell Array Enclosed with a Photodegradable Hydrogel in Microwells for Image-Based Cell Classification and Selective Photorelease of Cells

Single cell arrays provide an accurate classification of analyte cells through an image-based analysis of cellular phenotypes. Light-guided cell retrieval from a single cell array is a promising approach for the rapid and simple sorting of difficult to distinguish cells. In this study, we developed a single cell array enclosed with a photodegradable hydrogel in microwells to enable both comprehensive image-based single cell analysis and light-guided cell retrieval. In this system, individual cells became trapped in the microwells together with the photodegradable hydrogel at a high cell density on a chip regardless of cell type, adhesiveness, and motility. Fluorescence-stained model cells and vaccinated dendritic cells were identified by microscopic imaging and then selectively released through the light-induced degradation of the cell-embedding hydrogels. The target cells were selectively retrieved with a purity of >95% from the cell mixture through rapid photorelease, and the retrieved cells were confirmed to grow normally. Our results provide proof-of-principle that the photoresponsive microwell array serves as a versatile tool for image-based cell sorting in cellular researches and the manufacturing processes of high-performance cells.

Propagation dynamics of spin excitations along skyrmion strings

Magnetic skyrmions, topological solitons characterized by a two-dimensional swirling spin texture, have recently attracted attention as stable particle-like objects. In a three-dimensional system, a skyrmion can extend in the third dimension forming a robust and flexible string structure, whose unique topology and symmetry are anticipated to host nontrivial functional responses. Here we experimentally demonstrate the coherent propagation of spin excitations along skyrmion strings for the chiral-lattice magnet Cu₂OSeO₃. We find that this propagation is directionally non-reciprocal and the degree of non-reciprocity, as well as group velocity and decay length, are strongly dependent on the character of the excitation modes. These spin excitations can propagate over a distance exceeding 50 μm, demonstrating the excellent long-range ordered nature of the skyrmion-string structure. Our combined experimental and theoretical analyses offer a comprehensive account of the propagation dynamics of skyrmion-string excitations and suggest the possibility of unidirectional information transfer along such topologically protected strings.

Multiple-q noncollinear magnetism in an itinerant hexagonal magnet

Multiple-q spin order, i.e., a spin texture characterized by a multiple number of coexisting magnetic modulation vectors q, has recently attracted attention as a source of nontrivial magnetic topology and associated emergent phenomena. One typical example is the triple-q skyrmion lattice state stabilized by Dzyaloshinskii-Moriya interactions in noncentrosymmetric magnets, while the emergence of various multiple-q states of different origins is expected according to the latest theories. Here, we investigated the magnetic structure of the itinerant polar hexagonal magnet Y₃Co₈Sn₄, in which several distinctive mechanisms favoring multiple-q states are allowed to become active. Small-angle neutron-scattering experiments suggest the formation of incommensurate triple-q magnetic order with an in-plane vortex-like spin texture, which can be most consistently explained in terms of the novel four-spin interaction mechanism inherent to itinerant magnets. The present results suggest a new route to realizing exotic multiple-q orders and that itinerant hexagonal magnets, including the R ₃ M ₈Sn₄ family with wide chemical tunability, can be a unique material platform to explore their rich phase diagrams.

Low-Field Bi-Skyrmion Formation in a Noncentrosymmetric Chimney Ladder Ferromagnet

The real-space spin texture and the relevant magnetic parameters were investigated for an easy-axis noncentrosymmetric ferromagnet Cr_{11}Ge_{19} with Nowotny chimney ladder structure. Using Lorentz transmission electron microscopy, we report the formation of bi-Skyrmions, i.e., pairs of spin vortices with opposite magnetic helicities. The quantitative evaluation of the magnetocrystalline anisotropy and Dzyaloshinskii-Moriya interaction (DMI) proves that the magnetic dipolar interaction plays a more important role than the DMI on the observed bi-Skyrmion formation. Notably, the critical magnetic field value required for the formation of bi-Skyrmions turned out to be extremely small in this system, which is ascribed to strong easy-axis anisotropy associated with the characteristic helix crystal structure. The family of Nowotny chimney ladder compounds may offer a unique material platform where two distinctive Skyrmion formation mechanisms favoring different topological spin textures can become simultaneously active.

Electrochemical microdevices for rapid and on-site determination of the minimum inhibitory concentration of antibiotics

A tool for rapid selection of appropriate antibiotics may be useful to maximize the benefits of their effectiveness against severe infectious diseases.

Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging of the brain: Technique for suppression of enhancing venous signal

Purpose: Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging (BB-FSE) was performed to suppress enhancing venous signal and flow artifacts in the brain without sacrificing the T1-weighted imaging contrast.

Material and Methods: Twenty-five MR imaging sections (17 transverse and 8 coronal images) in 15 patients with various brain diseases were obtained by contrast-enhanced T1-weighted SE and BB-FSE images.

Results: In contrast-enhanced T1-weighted BB-FSE images, venous signal was significantly less and T1-weighted contrast of the brain was more evident. No differences in flow artifacts were found between the two imaging techniques. The interobserver agreements were good for the venous signal and flow artifacts using both techniques.

Conclusion: Contrast-enhanced T1-weighted BB-FSE imaging reduced the venous signal in the brain with maintaining T1-weighted contrast. This novel MR technique can be used when the suppression of enhancing venous signal is expected to improve the depiction of enhancing lesions in the brain.

A Single-Batch Fermentation System to Simulate Human Colonic Microbiota for High-Throughput Evaluation of Prebiotics

We devised a single-batch fermentation system to simulate human colonic microbiota from fecal samples, enabling the complex mixture of microorganisms to achieve densities of up to 10¹¹ cells/mL in 24 h. 16S rRNA gene sequence analysis of bacteria grown in the system revealed that representatives of the major phyla, including Bacteroidetes, Firmicutes, and Actinobacteria, as well as overall species diversity, were consistent with those of the original feces. On the earlier stages of fermentation (up to 9 h), trace mixtures of acetate, lactate, and succinate were detectable; on the later stages (after 24 h), larger amounts of acetate accumulated along with some of propionate and butyrate. These patterns were similar to those observed in the original feces. Thus, this system could serve as a simple model to simulate the diversity as well as the metabolism of human colonic microbiota. Supplementation of the system with several prebiotic oligosaccharides (including fructo-, galacto-, isomalto-, and xylo-oligosaccharides; lactulose; and lactosucrose) resulted in an increased population in genus Bifidobacterium, concomitant with significant increases in acetate production. The results suggested that this fermentation system may be useful for in vitro, pre-clinical evaluation of the effects of prebiotics prior to testing in humans.

Thermal Generation of Spin Current in an Antiferromagnet

The longitudinal spin Seebeck effect has been investigated for a uniaxial antiferromagnetic insulator Cr(2)O(3), characterized by a spin-flop transition under magnetic field along the c axis. We have found that a temperature gradient applied normal to the Cr(2)O(3)/Pt interface induces inverse spin Hall voltage of spin-current origin in Pt, whose magnitude turns out to be always proportional to magnetization in Cr(2)O(3). The possible contribution of the anomalous Nernst effect is confirmed to be negligibly small. The above results establish that an antiferromagnetic spin wave can be an effective carrier of spin current.

Comparison of the Growth of Lactobacillus delbrueckii, L. paracasei and L. plantarum on Inulin in Co-culture Systems

Lactobacillus delbrueckii TU-1, which apparently takes intact inulin into its cells and then degrades it intracellularly, was co-cultured in vitro with L. paracasei KTN-5, an extracellular inulin degrader; or L. plantarum 22A-3, a strain that is able to utilize fructose but not inulin; or both in order to prequalify inulin as a prebiotic agent in vivo. When L. delbrueckii TU-1 was co-cultured with L. paracasei KTN-5 on fructose or inulin, the growth of L. delbrueckii TU-1 on inulin was markedly higher than that of L. paracasei KTN-5, whereas the growth of L. delbrueckii TU-1 on fructose was much lower than that of L. paracasei KTN-5. These results suggest that L. delbrueckii TU-1 and L. paracasei KTN-5 were efficient at utilizing inulin and fructose, respectively. When L. plantarum 22A-3 was co-cultured with L. delbrueckii TU-1 on inulin, the growth of L. plantarum 22A-3 was enhanced by L. paracasei KTN-5 but not by L. delbrueckii TU-1, suggesting that the fructose moiety that L. paracasei KTN-5 released temporarily into the medium was “scavenged” by L. plantarum 22A-3. Thus, L. delbrueckii TU-1, L. paracasei KTN-5, and L. plantarum 22A-3 were then cultured altogether on inulin. The growth of L. delbrueckii TU-1 was unaffected but that of L. paracasei KTN-5 was markedly suppressed. This evidence suggests that prebiotic use of inulin supported the selective growth of intracellular inulin degraders such as L. delbrueckii rather than extracellular inulin degraders such as L. paracasei in the host microbiota.

A small compound targeting TACC3 revealed its different spatiotemporal contributions for spindle assembly in cancer cells

The mitotic spindle is assembled by the coordinated action of centrosomes and kinetochore microtubules. An evolutionally conserved protein family, transforming acidic coiled-coil (TACC), has been shown to be involved in this process. In humans, TACC3 is aberrantly expressed in a variety of human cancers, but its biological significance remains to be elucidated. Here, using a novel compound targeting TACC3, spindlactone (SPL), we show that the perturbation of TACC3 selectively inhibited the nucleation of centrosome microtubules in ovarian cancer cells. In contrast to centrosome microtubules, the kinetochore microtubules were robustly assembled, forming ectopic spindle poles that resulted in multipolar spindles. Interestingly, the extensive inhibition of TACC3 partially suppressed the nucleation of kinetochore microtubules. These dose-dependent effects of SPL were consistent with the results observed by the depletion of TACC3 and its binding partner, colonic and hepatic tumor overexpressed gene protein (TOGp). Although these proteins both have roles in the assembly of centrosome and kinetochore microtubules, their contributions were spatiotemporally different. Notably, SPL did not affect spindle assembly in normal cells. Furthermore, the oral administration of SPL significantly suppressed tumor growth in vivo. The unique mechanism of action of SPL not only enables it to be used as a tool to dissect the molecular basis of spindle assembly but also to provide a rationale for the use of TACC3 as a molecular target for cancer treatment. This rationale offers an opportunity to develop new strategies for cancer chemotherapy that overcome the limitations of microtubule toxins and expand their scope and clinical efficacy.

Inflammatory histopathogenesis of nasopalatine duct cyst: a clinicopathological study of 41 cases

OBJECTIVE

The aim of this study is to characterize immunohistochemical profiles of lining epithelia of nasopalatine duct cyst (NPC) as well as to correlate those findings with their clinicopathological features to understand the histopathogenesis of NPC.

MATERIALS AND METHODS

Forty-one surgical specimens from NPC were examined for clinical profiles and expression of keratin-7, 13, MUC-1, and P63 by immunohistochemistry, compared to radicular cyst (RC) and maxillary sinusitis.

RESULTS

Nasopalatine duct cyst was clinically characterized by male predominant occurrence: 44% of the cases involved tooth roots, and 70% with inflammatory backgrounds. Lining epithelia of NPCs without daughter cysts were immunohistochemically distinguished into three layers: a keratin 7-positive (+) ciliated cell layer in the surface, a keratin-13+ middle layer, and a MUC-1+/P63+ lower half, indicating that they were not respiratory epithelia, and the same layering pattern was observed in RC. However, those immunolocalization patterns of the main cyst lining with daughter cyst were exactly the same as those of daughter cyst linings as well as duct epithelia of mucous glands.

CONCLUSIONS

Two possible histopathogenesis of NPC were clarified: one was inflammatory cyst like RC and the other was salivary duct cyst-like mucocele.

A case of desmoplastic ameloblastoma arising in the maxillary alveolus: the origin and time-course changes in the early stage of tumour development observed on dental radiographs

In this article we report a case of desmoplastic ameloblastoma in which chronological changes in the early development can be observed on dental radiographs. The tumour grew very slowly and did not appear to have a strong potential for local extension like typical ameloblastomas. Radiological findings of our case suggest the tumour arose from the periodontal membrane. However, it was not possible to obtain conclusive histopathological evidence.

Complication of adenoid cystic carcinoma and sialolithiasis in the submandibular gland: report of a case and its etiological background

The authors report a case of adenoid cystic carcinoma (ACC) complicated with sialolithiasis of the submandibular gland. The patient was a 43-year-old female with a history of papillotubular carcinoma of the breast almost at the same time. She had noticed a swelling in her sublingual area for 10 years, which was later diagnosed by her dentist to be due to a sialolith in the left submandibular gland. After several years of observation, the patient was referred to have her left submandibular gland, containing the stone, surgically removed with a diagnosis of atrophic sialadenitis. Histopathologically, the submandibular gland was extensively replaced with fibrous granulation tissue, in which there were small but invasive foci of ACC. The present case indicates that ACC could arise in the background of chronic sialadenitis. It is suggested that long-standing sialadenitis cases should be carefully examined to exclude suspicion of malignancy before surgery.

Clinical study on prognostic factors for autotransplantation of teeth with complete root formation

Autotransplantation is often performed to replace a missing tooth, but tooth autotransplantation has been reported in fewer teeth with complete root formation than those with incomplete root formation. The aim of this prospective study was to evaluate the factors that affect the prognosis of autotransplantation of teeth with complete root formation. 109 patients with 117 transplants were studied. Of the 117 transplants investigated, 14 (12%) failed during the observation period. The overall 1-year survival rate was 96%; the 5-year survival rate was 84%. The major causes of failure were unsuccessful initial healing and replacement root resorption with periodontal inflammation. Factors significantly associated with unsuccessful transplantation, in single factor analysis, were age 40 years or more, molar tooth as donor, probing pocket depth to 4mm or more, history of root canal treatment, multi-rooted teeth and fixation with sutures. Pocket depth of 4mm or more and history of root canal treatment appeared to increase the risk of unsuccessful transplantation in multivariate analysis. It is suggested that the pocket depth of the donor tooth and history of root canal treatment are related to the healing of paratransplantal tissue and root resorption.

Thumb polydactyly with symphalangism in young children

Six cases of young children with thumb polydactyly in which the radial component was complicated by symphalangism are reported. Since the symphalangism was cartilaginous, plain X-rays showed an apparent joint space. However, its continuity was confirmed at surgery. Thumb polydactyly with symphalangism may be more common than previously expected.

Cementum-periodontal ligament complex regeneration using the cell sheet technique

BACKGROUND AND OBJECTIVE

In the present study we evaluated if a multilayered human periodontal ligament cell sheet could reconstruct the physiological architecture of a periodontal ligament-cementum complex.

MATERIAL AND METHODS

Human periodontal ligament cells were isolated and then cultured in dishes coated with a temperature-responsive polymer to allow cell detachment as a cell sheet. In the control group, human periodontal ligament cells were cultured in Dulbecco's modified Eagle's minimal essential medium containing 10% fetal bovine serum and 1% antibiotics. In the experimental group, human periodontal ligament cells were cultured in Dulbecco's modified Eagle's minimal essential medium and osteodifferentiation medium containing dexamethasone, ascorbic acid and beta-glycerophosphate. After 3 wk, scanning electron microscopy was carried out, in addition to staining for alkaline phosphatase activity and for calcium (using the Von Kossa stain). Then human periodontal ligament cell sheets were multilayered and placed onto dentin blocks. The constructs were transplanted subcutaneously into the back of immunodeficient rats. At 1 and 6 wk after transplantation, the animals were killed. Demineralized tissue sections were stained using hematoxylin and eosin, and Azan, and then analyzed.

RESULTS

After 3 wk of culture in osteodifferentiation medium, human periodontal ligament cells produced mineral-like nodules and also showed positive staining for alkaline phosphatase, calcium (Von Kossa) and mRNA expression of type I collagen. By contrast, in the control group only weak alkaline phosphatase staining was observed, the Von Kossa stain was negative and there was no mRNA expression of type I collagen. Six weeks after transplantation with human periodontal ligament cells cultured in osteodifferentiation medium, most of the dentin surfaces showed a newly immature cementum-like tissue formation and periodontal ligament with perpendicular orientation inserted into the newly deposited cementum-like tissue.

CONCLUSION

This study suggests that the multilayered temperature-responsive culture system can be used as a novel strategy for periodontal regeneration. The human periodontal ligament cell sheet technique may be applicable for regeneration of the clinical periodontal ligament-cementum complex.

Treatment of oesophageal ulcerations using endoscopic transplantation of tissue-engineered autologous oral mucosal epithelial cell sheets in a canine model

BACKGROUND

With the recent development of endoscopic submucosal dissection (ESD), large oesophageal cancers can be removed with a single procedure, with few limits on the resectable range. However, after aggressive ESD, a major complication that arises is postoperative inflammation and stenosis that can considerably affect the patient's quality of life.

AIMS

To examine a novel treatment combining ESD and the endoscopic transplantation of tissue-engineered cell sheets created using autologous oral mucosal epithelial cells, in a clinically relevant large animal model.

METHODS

Oral mucosal epithelial cells, harvested from beagle dogs, were cultured under normal conditions at 37 degrees C, on temperature-responsive dishes. After ESD (5 cm in length, 180 degrees in range), cell sheets were harvested by a simple reduction in temperature to 20 degrees C, and transplanted by endoscopy.

RESULTS

The transplanted cell sheets were able to adhere to and survive on the underlying muscle layers in the ulcer sites, providing an intact, stratified epithelium. Four weeks after surgery, complete wound healing, with no observable stenosis, was seen in the animals receiving autologous cell sheet transplantation. By contrast, noticeable fibrin mesh and host inflammation, consistent with the intermediate stages of wound healing, were observed in the control animals that received only ESD.

CONCLUSIONS

These findings in a clinically relevant canine model show the effectiveness of a novel combined endoscopic approach for the potential treatment of oesophageal cancers that can effectively enhance wound healing and possibly prevent postoperative oesophageal stenosis.

Linkage analysis between BCL3 and nearby genes on 19q13.2 and non-syndromic cleft lip with or without cleft palate in multigenerational Japanese families

OBJECTIVE

To investigate the linkage between candidate genes on chromosome 19 and cleft lip with or without cleft palate in Japanese using a parametric method.

MATERIALS AND METHODS

After informed consent was obtained, blood samples were drawn from 90 individuals in 14 families, 30 of whom were affected, and genomic DNAs were extracted. PCR-amplified products using four microsatellite markers, D19S178, BCL3, APOC2[007/008] and APOC2[AC1/AC2] located in 19q13.2, were separated by 8% polyacrylamide gel electrophoresis. Linkage analysis was carried out using the MLINK and LINKMAP programs, and logarithm of odds (LOD) scores were calculated for each family.

RESULTS

Before undertaking linkage analysis, we analyzed 74 healthy Japanese subjects and found racial differences in that the observed number of alleles and their heterozygosity were lower in Japanese than in Caucasians, and that both populations tended to show a different allele distribution. In 14 families, two-point maximum LOD score (Zmax) for BCL3 was 0.341 and multi-point Zmax was less than -2 excluding linkage. But in 9 families with left and bilateral CL/P, two-point Zmax for APOC2[AC1/AC2] was 1.701 and multi-point Zmax at APOC2 locus was 1.909.

CONCLUSION

The LOD score was relatively high but provided no evidence of linkage for CL/P to BCL3 and nearby genes in Japanese subjects.

Clinical significance and usefulness of quantification of telomerase activity in oral malignant and nonmalignant lesions

We quantified telomerase activity (TA) in patients with oral and maxillofacial malignant and nonmalignant lesions, and compared it with their clinical status and grade of malignancy. Fifty-two malignant and 52 nonmalignant lesions were analyzed. All malignant lesions were pathologically diagnosed as oral squamous cell carcinoma (OSCC). Normal gingival tissue served as a control. These specimens were obtained by biopsy or surgical resection, and stored at -80 degrees C until use. TA was quantified by a fluorescence-based TRAP method. TA levels ranged from 0.00 to 95.24 (average 33.24)U/microgP in 52 malignant lesions, and from 0.00 to 79.35 (average 11.91)U/microgP in 52 nonmalignant lesions (P < 0.0001). TA was detected in 96.2% of malignant and 65.4% of nonmalignant lesions. There was no relationship between TA levels and clinical stages or YK classification. However, under WHO classification, there were significant differences (P < 0.05) between Grades I and III or II + III. Among nonmalignant lesions, epithelial dysplasia showed a significantly higher TA level than that of oral lichen planus (P < 0.05) and other benign lesions (P < 0.0001). Oral lichen planus also significantly differed from other benign lesions (P < 0.05). These results suggest that TA is related to the histological grade of malignancy, and is also useful as a prognostic predictor for precancerous lesions and conditions.

Effect of local hyperthermia on metastases in oral squamous cell carcinoma

In this experimental study, hamsters with oral squamous cell carcinoma (O-1N), which has a high potential for lymph node metastasis, received treatment with local hyperthermia. The effect of hyperthermia on regional lymph node metastases was examined pathologically. O-1N was heated twice, each session consisting of radiofrequency capacitive heating (13.56 MHz) for 40 min at 43 degrees C. Cervical lymph nodes were excised 14, 17, 21, and 28 days after heating and were examined histologically. Hamsters in the sham and control groups were killed on the same days and specimens were examined in a same manner. The incidence of lymph node metastasis was significantly lower in the hyperthermia group (36.4%) than in the sham (68.5%) and control (65.0%) groups (both P=0.02). The patterns of lymph node metastasis in the sham and control groups were more advanced than that in the hyperthermia group. The incidence of lymph node metastasis was very low (7.7%) in hamsters with no evidence of tumour after hyperthermia. On multivariate analysis, hyperthermia correlated with inhibition of cervical lymph node metastasis (P=0.02). Our findings suggest that local hyperthermia inhibits lymph node metastasis when the primary tumour responds histologically to treatment.

Unprecedented sugar-dependent in vivo antitumor activity of carbohydrate-pendant cis-diamminedichloroplatinum(II) complexes

Eight carbohydrate-pendant platinum(II) complexes have been synthesized from carbohydrate-diamine conjugates. D-Glucose, D-mannose, D-galactose, D-xylose, and L-glucose are attached to the dichloroplatinum(II) moiety by 1,3- or 1,2-diaminopropane chelates through with an O-glycoside bond. All the carbohydrate moieties reduced the toxicity inherent with platinum(II) complexes.

The exact expression of glial fibrillary acidic protein (GFAP) in trigeminal ganglion and dental pulp

The expression in various cell types of peripheral tissues of glial fibrillary acidic protein (GFAP), first discovered as an intermediate filament specific for astrocytes, remains controversial owing to numerous reports of a wide distribution for GFAP-immunoreactivity in various cells. The present study employed immunohistochemistry to investigate the precise expression of GFAP in the dental pulp and trigeminal ganglion of adult rats and wild-type mice as well as GFAP-knockout mice. The exhibition of GFAP-immunoreactivity in the trigeminal ganglion was further examined by a reverse transcription polymerase chain reaction (RT-PCR) technique, and in situ hybridization histochemistry using a specific cRNA probe prepared by us. The immunoreaction for GFAP was recognizable in the axons, Schwann cells, and the fibroblasts in the dental pulp of rats and wild-type littermate mice. However, mice with null mutations in the GFAP gene remained immunoreactive for GFAP in all these locations. Intense GFAP-immunoreactivity was found in a small number of satellite cells in the trigeminal ganglion in all animals examined in this study. RT-PCR analysis demonstrated bands for the GFAP gene corresponding to the length expected from the primer design in the samples of trigeminal ganglion and dental pulp. In situ hybridization histochemistry also showed intense signals for GFAP mRNA in some satellite cells of the trigeminal ganglion, but never in the neurons. These data suggest that the GFAP-immunoreactive molecules in the pulpal axons and fibroblasts react non-specifically with the polyclonal antibody and are probably a closely related type of intermediate filament.

Functional expression of alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors precedes the development of cholinergic phenotype in embryonic rat septal cells in culture

We examined the development of cholinergic neuronal functions and alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) responses in cultured embryonic rat septal cells. Choline acetyltransferase activity was increased from 4 to 6 days in culture and reached a plateau at day 8. Acetylcholine release was increased from 6 to 8 days in culture. AMPA-induced increase in intracellular Ca(2+) level was observed at 3 days in culture and most of the AMPA-responsive cells coincided with high-K(+) responsive cells. These results suggest that cholinergic neurons develop their neuronal functions about 8 days under cultured conditions, and functional expression of AMPA receptors precedes the cholinergic functional development.

Decrease in level of APG-2, a member of the heat shock protein 110 family, in murine brain following systemic administration of kainic acid

APG-2 belongs to the heat shock protein 110 family. Although kainic acid (KA)-induced seizures are known to elicit expression of inducible heat shock protein 70 (HSP70) in the brain, no investigation has been carried out on the APG-2 level after excitatory amino acid-induced seizures. By means of an immunoblot assay, we determined the levels of HSP70 and APG-2 in discrete brain structures of mice after a single intraperitoneal injection of KA or N-methyl-D-aspartic acid (NMDA). APG-2 level was significantly decreased in frontal cortex, hippocampus, and striatum three days after the administration of KA, while HSP70 level was increased in these regions following the administration. In any of these regions, APG-2 levels were returned to the control levels 10 days after the administration. However, no significant changes were observed in levels of both HSP70 and APG-2 in hypothalamus, midbrain, medulla-pons, and cerebellum of the mice. By contrast, NMDA administration did not significantly affect both levels in any of the regions examined. These findings indicate that the transient decrease in APG-2 expression is one of the intracellular events elicited by signals peculiar to KA, but not by those peculiar to NMDA, in telencephalon of murine brain.

Sugar-pendant diamines

A set of 1,3-propanediamine derivatives connected to carbohydrates (5) has been prepared in four steps from peracetylated sugar and 1,3-dibromo-2-propanol in 60-73% yields. D-Glucose, D-mannose, D-galactose, D-xylose, D-ribose, and maltose are utilized as sugar molecules in this work. The diamine moiety was connected to the C1 carbon of the glycopyranose ring via an O-glycoside bond. All of the anomeric configurations and sugar puckering conformations, except in the D-maltose derivative, were determined by X-ray crystallography of the diazido or dibromo precursors. While glycosidation of peracetylated galactopyranose with 1,3-dibromo-2-propanol in the presence of boron trifluoride afforded both anomers, the neighboring group participation of the 2-acetoxy group yielded a single anomer for the other substrates. This method has been used to synthesize a library of sugar-pendant diamines including an OH-protected derivative (6), and an N,N'-diisopropyl-substituted derivative (7). A similar series of reactions using 2,3-dibromo-1-propanol gave ethylenediamine-type derivatives (11), and bis(bromomethyl)bis(hydroxymethyl)methane (12) gave bisglucose-pendant derivatives (16).

[Usefulness of multiphase helical CT in the diagnosis of pituitary microadenoma]

The purpose of this study was to determine the value of multiphase helical CT (MHCT) in the diagnosis of pituitary microadenoma. Twenty-two patients with clinically suspected microadenoma were examined. Coronal pre-contrast CT was initially carried out. Three series of helical scanning using 1-mm collimation, 1-mm/s table speed, and 1-mm interval reconstruction covering the entire pituitary gland were performed with an intravenous injection of contrast medium. Immediately after MHCT, delayed CECT was performed. Twenty microadenomas (3-10 mm, mean: 5.5 mm) were surgically confirmed. MHCT could depict all 20 tumors, while pre-contrast CT and delayed CECT showed 4 and 12 of 20 tumors, respectively. MHCT was useful in the diagnosis of pituitary microadenoma owing to its high spatial resolution and extensive coverage.

[Clinical result of thermochemoradiotherapy for advanced head and neck cancer]

Since 1986, we have applied thermochemo (CDDP) therapy combined with radiotherapy to 18 patients with 25 advanced and/or recurrent head and neck cancers (thermochemoradiotherapy: TCR). In this report, the effects of TCR were compared with those of radiochemotherapy (RC) without hyperthermia for 22 patients with 27 cancers before 1985 in our department. Thermochemotherapy was performed twice a week, for a total of 8.8 times on average. Three kinds of heating system were used: a radiofrequency system, a microwave system, and a RF interstitial system. In the TCR group, 11 lesions (44.0%) showed a complete response (CR), 12 lesions (48.0%) a partial response (PR), and 2 lesions (8.0%) no change (NC). Therefore, the total response rate was 92.0%. After treatment with only RC, 5 lesions (18.5%) showed a CR, 12 lesions (44.5%) a PR, and 10 lesions (37.0%) NC, giving a total response rate of 63.0%. There was a significant difference in the CR and total response rate between these two groups. Furthermore, the 5-year cumulative local control and survival rates in the TCR group were 68.2% and 44.4%, and in the RC group were 22.2% and 18.2%, respectively. There was a significant difference in the local control rate between these two groups. In conclusion, thermochemoradiotherapy is an effective strategy for patients with advanced head and neck cancers.

Cold pain prolongs gastric emptying of liquid but not solid meal: an electrical impedance tomography (EIT) study

Stressful stimuli are reported to affect gastric emptying. However, methods for measuring gastric emptying are, in themselves, stressful. Electrical impedance tomography (EIT) is a method for measuring gastric emptying noninvasively. We used EIT to measure gastric emptying of liquid and solid meals to determine the effect of cold pain stress on gastric emptying. EIT (DAS-01P APT system; University of Sheffield, UK) was carried out in six healthy women (age, 21.6 +/- 0.4 [mean +/- SD] years) who had ingested a liquid (potage, 263 g; 139 kcal) or solid (beef patty, 205 g; 435 kcal) test meal. Cold pain stimuli consisted of repeated immersions of the subject's non-dominant hand into ice water (4 degrees C) for 1 min, with a 15-s recovery period between immersions, for a total of 20 min. For the control stimulus, water at 37 degrees C was used. The cold pain stimulus was applied immediately after the ingestion of a test meal. All studies were carried out randomly in each subject at intervals of more than 1 week. With cold pain, the half emptying time of the liquid meal was significantly greater than that with the control stimulus (47.6 +/- 26.1 min vs 28.1 +/- 10.8 min, P < 0.05). For the solid meal, the half emptying time did not differ between stimuli (101.9 +/- 44.8 min with cold pain vs 92.6 +/- 30.5 min with control stimulus). There were no significant differences in lag time between the liquid and solid meals. Cold pain stress delayed gastric emptying of liquid but not solid meals.