Electric Quadrupolar Contributions in the Magnetic Phases of UNi_{4}B.

We present acoustic signatures of the electric quadrupolar degrees of freedom in the honeycomb-layer compound UNi_{4}B. The transverse ultrasonic mode C_{66} shows softening below 30 K both in the paramagnetic phase and antiferromagnetic phases down to ∼0.33 K. Furthermore, we traced magnetic field-temperature phase diagrams up to 30 T and observed a highly anisotropic elastic response within the honeycomb layer. These observations strongly suggest that Γ_{6}(E_{2g}) electric quadrupolar degrees of freedom in localized 5f^{2} (J=4) states are playing an important role in the magnetic toroidal dipole order and magnetic-field-induced phases of UNi_{4}B, and evidence some of the U ions remain in the paramagnetic state even if the system undergoes magnetic toroidal ordering.

Evidence for the Single-Site Quadrupolar Kondo Effect in the Dilute Non-Kramers System Y_{1-x}Pr_{x}Ir_{2}Zn_{20}.

Acoustic signatures of the single-site quadrupolar Kondo effect in Y_{0.966}Pr_{0.034}Ir_{2}Zn_{20} are presented. The elastic constant (C_{11}-C_{12})/2, corresponding to the Γ_{3}(E)-symmetry electric-quadrupolar response, reveals a logarithmic temperature dependence of the quadrupolar susceptibility in the low-magnetic-field region below ∼0.3 K. Furthermore, the Curie-type divergence of the elastic constant down to ∼1 K indicates that the Pr ions in this diluted system have a non-Kramers ground-state doublet. These observations evidence the single-site quadrupolar Kondo effect, as previously suggested based on specific-heat and electrical-resistivity data.

Spin rotation induced by applied pressure in the Cd-doped Ce2RhIn8 intermetallic compound.

The pressure evolution of the magnetic properties of the Ce2RhIn7.79Cd0.21 heavy fermion compound was investigated by single crystal neutron magnetic diffraction and electrical resistivity experiments under applied pressure. From the neutron magnetic diffraction data, up to P = 0.6 GPa, we found no changes in the magnetic structure or in the ordering temperature T N = 4.8 K. However, the increase of pressure induces an interesting spin rotation of the ordered antiferromagnetic moment of Ce2RhIn7.79Cd0.21 into the ab tetragonal plane. From the electrical resistivity measurements under pressure, we have mapped the evolution of T N and the maximum of the temperature dependent electrical resistivity (T MAX) as a function of the pressure (P ≲ 3.6 GPa). To gain some insight into the microscopic origin of the observed spin rotation as a function of pressure, we have also analyzed some macroscopic magnetic susceptibility data at ambient pressure for pure and Cd-doped Ce2RhIn8 using a mean-field model including tetragonal crystalline electric field (CEF). The analysis indicates that these compounds have a Kramers doublet Γ 7 - -type ground state, followed by a Γ 7 + first excited state at Δ1 ∼ 80 K and a Γ6 second excited state at Δ2 ∼ 270 K for Ce2RhIn8 and Δ2 ∼ 250 K for Ce2RhIn7.79Cd0.21. The evolution of the magnetic properties of Ce2RhIn8 as a function of Cd doping and the rotation of the direction of the ordered moment for the Ce2RhIn7.79Cd0.21 compound under pressure suggest important changes of the single ion anisotropy of Ce3+ induced by applying pressure and Cd doping in these systems. These changes are reflected in modifications in the CEF scheme that will ultimately affect the actual ground state of these compounds.

How I do it: underwater endoscopic ear surgery for plugging in superior canal dehiscence syndrome.

BACKGROUND: Underwater endoscopic ear surgery does not require suction and so protects the inner ear from unexpected aeration that may damage its function in the treatment of labyrinthine fistula. A method of underwater endoscopic ear surgery is proposed for the treatment of superior canal dehiscence. METHODS: Underwater endoscopic ear surgery was performed for plugging of the superior semicircular canal through the transmastoid approach. Saline solution was infused into the mastoid cavity through an Endo-Scrub Lens Cleaning Sheath. The tip of the inserted endoscope was filled completely with saline water. RESULTS: Using this underwater endoscopic view, the canal was clearly dissected to expose the semicircular canal membranous labyrinth and dehiscence area. No particular complication occurred during the surgical procedure. CONCLUSION: The underwater endoscopic ear surgery technique for plugging in superior canal dehiscence secures an excellent visual field and protects the inner ear from unexpected aeration.

Minimally invasive transnasal approach to infratemporal fossa abscess.

BACKGROUND: Infratemporal fossa abscess following odontogenic infection is not rare, and usually occurs as a sequela of dental disease. Infratemporal fossa abscess was previously treated with the combination of buccal incision and temporal incision, or via a transoral approach. METHOD: This paper reports a case of infratemporal fossa abscess in a 51-year-old female. RESULTS: The abscess was drained transnasally via an endoscopic modified medial maxillectomy approach, preserving the inferior turbinate and nasolacrimal duct. The pain remitted the next day and trismus had diminished in one week. CONCLUSION: The transnasal approach with endoscopic modified medial maxillectomy is a direct, minimally invasive method that provides a direct field of view for drainage of infratemporal fossa abscess. This approach is recommended for infratemporal fossa abscess.

Intraoral drainage under surgical microscopy with tonsillectomy for parapharyngeal abscesses.

BACKGROUND: An intraoral approach combined with tonsillectomy has been used to access the parapharyngeal space. However, the utility of this technique for parapharyngeal abscesses in paediatric patients has not been investigated. This paper describes an intraoral drainage technique combined with tonsillectomy for treating children with a parapharyngeal abscess that obviates the need for skin incision. METHODS: Clinical case records are presented, along with a description of the surgical procedure accompanied by a video clip. RESULTS: Both cases encountered involved paediatric parapharyngeal space abscesses that extended to the skull base. The patients underwent an intraoral approach combined with tonsillectomy performed under surgical microscopy; this resulted in a good post-operative course without complications. CONCLUSION: To our knowledge, no previous reports have addressed the use of surgical microscopy to help access the parapharyngeal space. The procedure described herein, performed under surgical microscopy, was specifically helpful in enabling access to these challenging spaces; it also meant that surgical procedures could be recorded clearly and findings shared with other medical staff.

Giant cell reparative granuloma of the temporal bone successfully resected with preservation of hearing.

OBJECTIVE: To describe a case of giant cell reparative granuloma of the temporal bone which extended into the middle-ear cavity, and which was successfully treated surgically via a transmastoid approach, with hearing preservation. CASE: A 37-year-old man presented with a one-year history of right-sided hearing loss, complicated by a three-month history of otalgia and a sensation of aural fullness. Computed tomography and magnetic resonance imaging demonstrated an osteolytic tumour lesion in the right temporal bone. The diagnosis was confirmed by biopsy from the mastoid lesion. INVESTIGATION AND INTERVENTION: Pure-tone audiometry, computed tomography and magnetic resonance imaging were conducted, followed by total resection. RESULT: The giant cell reparative granuloma of the temporal bone was completely resected, with preservation of hearing. CONCLUSION: Although this patient's giant cell reparative granuloma of the temporal bone extended into the middle-ear cavity, total resection was achieved, with preservation of hearing. To the best of our knowledge, hearing preservation following resection of giant cell reparative granuloma of the temporal bone has not previously been reported.

Therapeutic potential of cholesteryl O-acyl α-glucoside found in Helicobacter pylori.

Steryl glycosides are derivatives of sterols where the 3ß-hydroxy group is glycosylated. Some of them are further converted to steryl O-acyl glycosides. Steryl glycosides and their derivatives are widely distributed in plants, algae, and fungi, but are relatively rarely distributed in bacteria and animals. Accumulating evidence suggests that glycosylation of sterols not only modifies physicochemical properties of cell membranes but also alters immunogenicity of the cells. Helicobacter pylori, that colonizes the stomach and causes gastric diseases, is auxotrophic for cholesterol, so that it extracts this lipid from plasma membranes of epithelial cells of the host stomach. Since incorporation of cholesterol promotes immune responses of the host, Helicobacter pylori converts cholesterol to cholesteryl glucoside (ChG) and then to cholesteryl 6'-O-acyl glucoside (ChAcG) to evade the immune surveillance. We have found that ChAcG thus produced is specifically recognized by invariant Vα14-Jα18 TCR(+) (Vα14) NKT cells in a CD1-dependent manner. We have also found that activation of Vα14 NKT cells by administration of ChAcG retains homeostasis of immunity upon exposure to allergens and reduces the incidence of allergy. In this article, overview of immunological functions of steryl glycosides with an emphasis on the immunoregulatory functions of ChAcG, is demonstrated.

Viral level is an indicator of long-term outcome of hepatitis B virus e antigen-negative carriers with persistently normal serum alanine aminotransferase levels.

The association between viral level and the long-term outcomes of hepatitis B virus (HBV) carriers who test negative for hepatitis B virus e antigen (HBeAg) but have persistently normal serum alanine aminotransferase levels (PNALT) remains unclear. We examined hepatocarcinogenesis, hepatitis reactivation, predictive factors and the time course of HBV DNA levels during follow-up in 104 HBeAg-negative Japanese carriers with PNALT. During a mean follow-up period of 6.4 ± 3.4 years, 5 patients (4.8%) had hepatocarcinogenesis and 14 (13.5%) had hepatitis reactivation. At 5 and 10 years, the cumulative rates of hepatocarcinogenesis were 2.4% and 9.9%, while those of hepatitis activation were 13.7% and 15.5%, respectively. An HBV DNA level of ≥5 log10 copies/mL was the sole predictor of hepatocarcinogenesis with a univariate analysis. An HBV DNA level of ≥5 log10 copies/mL and an alanine aminotransferase (ALT) level of >20 to ≤40 IU/L were independent predictors of hepatitis reactivation in a Cox model. Because there was no association between hepatocarcinogenesis and ALT activity, the HBV DNA level was considered an essential predictor. In addition, the baseline HBV DNA level was related to the future level and was not subject to wide fluctuations. Our results showed that an HBV DNA level of ≥5 log10 copies/mL predicts subsequent hepatocarcinogenesis and hepatitis reactivation in HBeAg-negative carriers with PNALT. As the baseline HBV DNA level reflects the future level, appropriate clinical management according to the viral level is expected to decrease future risk.

Precipitating factors in the pathogenesis of peritonsillar abscess and bacteriological significance of the Streptococcus milleri group.

Peritonsillar abscess (PTA) is conventionally considered to be a complication of acute tonsillitis, but no pathogenical association has been demonstrated. To investigate the precipitating factors in the pathogenesis of PTA, the clinical status of 117 patients with PTA and 78 patients with peritonsillar cellulitis (PC) were reviewed, comparing them with 188 cases of acute tonsillitis as a control group. The period between the onset of symptoms and the date of starting hospitalized medication was 4 to 5 days in all the three groups, with no significant differences. Higher prevalence of smoking habit was noted in the PTA group (odds ratio, 1.92; 95% confidence interval, 1.17-3.16). Bacteriological culture revealed that 55 of 67 aerobic isolates were Streptococcus subspecies, with the Streptococcus milleri group (SMG) as the most common (20 isolates). Twenty-three anaerobic species were isolated. Only 51% of the patients with neither the SMG nor anaerobic bacteria were smokers, whereas 90% of the patients with both the SMG and anaerobic bacteria were smokers. We hypothesize that delay or failure to receive medical care do not contribute to the pathogenesis of PTA or PC, and that smoking is positively correlated with the occurrence of PTA, as well as the bacteriological character.

Congenital cholesteatoma of mastoid region manifesting as acute mastoiditis: case report and literature review.

OBJECTIVES: We report an extremely rare case of congenital cholesteatoma of the mastoid region, presenting as acute mastoiditis. We also review the 16 previously reported cases of congenital cholesteatoma of the mastoid region. CASE REPORT: A 65-year-old man presented with left-sided, post-auricular swelling and pain. Acute mastoiditis was diagnosed, with computed tomography demonstrating destruction of the bony plates of the posterior cranial fossa and sigmoid sinus. Initial surgery revealed a cholesteatoma in the mastoid, with no extension into the aditus ad antrum or attic. These findings were confirmed by pathological and immunohistochemical analysis of the surgical specimen, the latter using involucrin. The cholesteatoma matrix was completely removed in a second operation. CONCLUSIONS: Including this case, only four of the 17 reported cases of congenital cholesteatoma of the mastoid region showed post-auricular pain or swelling, indicating acute mastoiditis. Clinicians should bear in mind that congenital cholesteatoma may be present in patients presenting with mastoiditis, particularly adults.

Pressure and magnetic field tuned quantum critical point in the Kondo antiferromagnet CePtZn.

We report magnetization, heat capacity and electrical resistivity measurements on CePtZn, which crystallizes in the orthorhombic TiNiSi type structure. Magnetization and electrical resistivity on the iso-structural series of compounds Ce(1-x)La(x)PtZn (x = 0.1, 0.2 0.5 and 1) were also carried out. The electrical resistivity of CePtZn was also measured in external magnetic fields up to 12 T and under pressures up to 2.66 GPa. We find that CePtZn is a dense Kondo lattice, ordering antiferromagnetically at T(N) = 1.7 K, with a comparable Kondo temperature. The magnetic transition temperature, T(N), is continuously suppressed both by the magnetic field and pressure and [Formula: see text] around 5-6 T and at 1.2 GPa, respectively. Non-Fermi liquid behavior of resistivity at 4 T and 1.2 GPa and logarithmic divergence of the heat capacity, C(4f)/T, at 6 T in a limited temperature region strongly suggest the emergence of a quantum critical point as [Formula: see text].

Connection between charge fluctuations and the coherent temperature in the heavy-fermion system SmOs4Sb12: a {121, 123}Sb NQR study.

We report {121, 123}Sb nuclear quadrupole resonance measurements under pressure in a novel heavy fermion (HF) system SmOs4Sb12. The nuclear spin-spin relaxation rate 1/T{2} exhibits a distinct peak near the coherent temperature of the Kondo effect. The isotope effect of 121Sb and 123Sb indicates that the peak in 1/T{2} is electrical in origin. The connection between the peak in 1/T{2} and the development of coherency of the Kondo effect is robust even under pressure. It is conjectured that charge fluctuation plays an important role in forming the HF state in SmOs4Sb12.

Nonmagnetic indenter-type high-pressure cell for magnetic measurements.

An indenter-type high-pressure cell has been developed for electric and magnetic measurements in low-temperature and high-magnetic-field environments. The maximum pressure achieved at low temperatures is more than 4.5 GPa, which is higher than that of a conventional piston-cylinder cell. The typical sample space at maximum pressure is 1.6 mm in diameter and approximately 0.7 mm in depth, and magnetic measurements such as ac-susceptibility and nuclear magnetic resonance can be performed using a miniature coil. All the components of the indenter cell are made of nonmagnetic materials that have enough thermal conductivity for low-temperature experiments using a 3He/4He dilution refrigerator. Another indenter-type cell designed for a commercial superconducting quantum interference device magnetometer is also reported.

Temperature, composition, and hydrogen isotope effect in the hydrogenation of CO on amorphous ice surface at 10-20 K.

An experiment on the addition reaction of a D atom (deuteration) to CO on a cold ice surface is performed by deuterium atom exposure of three types of samples (pure solid CO, CO-capped H2O ice, and CO-H2O mixed ice) at 10-20 K. The variation of IR absorption spectra for the samples was measured by a Fourier transform infrared spectrometer during exposure to deuterium atoms. Reactions on pure solid CO were observed only at 10 K, while reactions on CO-capped H2O ice and CO-H2O mixed ice were observed to proceed even at 20 K. This indicates that the coexistence of H2O at the surface raises the reactive temperature. In addition, the experiment on H atom exposure was also carried out at 15 K to compare the reaction rate constant between the H and D atoms. The ratio of reaction rate constant kD/kH obtained is about 0.08 at 15 K. The authors provide information on the potential energy for the H+CO reaction at the surface by using the ratio kD/kH and by a model calculation of the potential tunneling with the asymmetric Eckart potential.

The role of mass spectrometry to study the Oklo-Bangombé natural reactors.

The discovery of the existence of chain reactions at the Oklo natural reactors in Gabon, Central Africa in 1972 was a triumph for the accuracy of mass spectrometric measurements, in that a 0.5% anomaly in the (235)U/(238)U ratio of certain U ore samples indicated a depletion in (235)U. Mass spectrometric techniques thereafter played a dominant role in determining the nuclear parameters of the reactor zones themselves, and in deciphering the geochemical characteristics of various elements in the U-rich ore and in the surrounding rock strata. The variations in the isotopic composition of a large number of elements, caused by a combination of nuclear fission, neutron capture and radioactive decay, provide a powerful tool for investigating this unique geological environment. Mass spectrometry can be used to measure the present-day elemental and isotopic abundances of numerous elements, so as to decipher the past history of the reactors and examine the retentivity/mobility of these elements. Many of the fission products have a radioactive decay history that have been used to date the age and duration of the reactor zones, and to provide insight into their nuclear and geochemical behavior as a function of time. The Oklo fission reactors and their near neighbor at Bangombé, some 30 km to the south-east of Oklo, are unique in that not only did they become critical some 2 x 10(9) years ago, but also the deposits have been preserved over this period of geological time. The long-term geochemical behavior of actinides and fission products have been extensively studied by a variety of mass spectrometric techniques over the past 30 years to provide us with significant information on the mobility/retentivity of this material in a natural geological repository. The Oklo-Bangombé natural reactors are therefore geological analogs that can be evaluated in terms of possible radioactive waste containment sites. As more reactor zones were discovered, it was realized that they could be classified into two groups according to their burial depth in the Oklo mine-site. Reactor Zones 10, 13, and 16 were buried more deeply, and were therefore less weathered than the other zones. The less-weathered zones are of great importance in mobility/retentivity studies and therefore to the question of radioactive waste containment. Isotopic studies of these natural reactors are also of value in physics to examine possible variations in fundamental constants over the past 2 billion years.

Role of intraoperative enteroscopy for surgical decision making with Crohn's disease.

BACKGROUND: This study aimed to assess the role of intraoperative enteroscopy (IOE) in determining surgical treatment. METHODS: The IOE procedure was performed for 30 patients with Crohn's disease. The degree of stricture and the presence of active ulcer were examined. Preoperative diagnoses and intraoperative findings obtained by inspection and palpation were noted and compared with the IOE findings. RESULTS: Of the 78 intestinal strictures observed by IOE (42%), 33 were not found by preoperative examination. Of the 45 strictures confirmed by IOE to be severe (<15 mm in diameter), 8 were judged to be mild (15-25 mm in diameter) or were not even identified by intraoperative inspection and palpation. Active ulcer was found at 12 of 33 mild strictures, and all 12 strictures were surgically corrected. Of 11 severe strictures detected by IOE at previous surgical sites, 9 were found preoperatively, and 4 were judged to be mild on the basis of inspection and palpation. Stricture was found at the ileocecal valve by IOE in seven patients, but was not diagnosed preoperatively in two of these patients. CONCLUSION: Intraoperative enteroscopy provides useful information regarding the status of the lumen in patients with Crohn's disease.

Constitutive IL-8 expression in cancer cells is associated with mutation of p53.

We previously reported that most cancer cell lines constitutively express various cytokines including IL-8. But how IL-8 gene expression is regulated in cancer cells is still unclear. p53 tumor suppressor gene plays an important role in the regulation of transcription and is mutated in cancer cell lines. We investigated whether p53 status affects the constitutive expression of IL-8 in human cancer cells. SUIT-2 and RERF-LCOK cancer cells constitutively produced high levels of IL-8 in culture medium. Both cell lines were shown to carry a p53 mutation, and constitutive NF-kappaB transcriptional activity. To analyze whether p53 status mediates IL-8 expression, the effect of wild-type p53 (wt-p53) gene transfer on activation of NF-kappaB was determined in both cell lines. ELISA showed that the IL-8 concentration in medium decreased dose dependently by transient expression of wt-p53. Western-blot analysis showed no marked change in NF-kappaB protein levels in cell nuclei. EMSA showed no repression of NF-kappaB binding activity after transient expression of wt-p53. In contrast, luciferase reporter studies indicated that transcriptional activity of NF-kappaB is suppressed by transfection of wt-p53. These results show that wt-p53 gene transfer inhibits IL-8 production and NF-kappaB transcription activity in cancer cells and suggest that constitutive IL-8 production in cancer cells is associated with mutation of p53.

Involvement of Rho-kinase in inflammatory and neuropathic pain through phosphorylation of myristoylated alanine-rich C-kinase substrate (MARCKS).

Myristoylated alanine-rich C-kinase substrate (MARCKS) is a major in vivo substrate for protein kinase C in the brain and has been implicated in cellular processes associated with cytoskeletal restructuring such as synaptic trafficking and neurotransmitter release. A phosphorylation-site specific antibody against Ser159-phospho-MARCKS (pS159-Mar-Ab) revealed that MARCKS is phosphorylated at Ser159 by Rho-kinase and that its phosphorylation is inhibited by the Rho-kinase specific inhibitor H-1152. Since the function of MARCKS is regulated by phosphorylation at multiple sites, here we examined the involvement of Rho-kinase in relation to phosphorylation of MARCKS at Ser159 in inflammatory and neuropathic pain by H-1152. When intrathecally administered 10 min before s.c. injection of formalin, H-1152 at 10 and 100 ng attenuated the second-phase, but not the first-phase, pain-like behaviors in the formalin test. Neuropathic pain induced by selective L5 spinal nerve transection was also relieved by intrathecal injection of H-1152. Nitric oxide synthase activity visualized by NADPH diaphorase histochemistry increased in the superficial layer of the spinal cord 30 min after formalin injection and 7 days after nerve transection, which were blocked by H-1152. Phosphorylation of MARCKS at Ser159 was detected in the spinal cord by pS159-Mar-Ab and the level of phosphorylation increased in the superficial layer after nerve transection. In contrast, immunoreactivities of neuronal nitric oxide synthase and MARCKS did not change significantly in the spinal cord before and after nerve transection. Taken together, the present study demonstrates that Rho-kinase is involved in inflammatory pain and the maintenance of neuropathic pain through phosphorylation of MARCKS at Ser159.

Different photocatalytic fate of amido nitrogen in formamide and urea.

In the comparison of formamide and urea photocatalytic degradation, despite their similar structures, the final fate of bound nitrogen under illumination with TiO2 has shown a different behaviour; both the rate and the ratio of NH4+ and NO3- ion evolution seem not to be linked to the initial nitrogen oxidation state, but to the carbon oxidation state.