Suppressive effects of 1,4-dihydroxy-2-naphthoic acid administration on bone resorption

SUMMARY

The main component of the metabolic by-products of fermentation by Propionibacterium freudenreichii ET-3 is 1,4-dihydroxy-2-naphthoic acid (DHNA), which has a naphthoquinone skeleton, as in vitamin K2. This study showed that DHNA improved bone mass reduction with osteoporosis model mice caused by FK506.

INTRODUCTION

Growth of the intestinal bacterium Lactobacillus bifidus is specifically facilitated by DHNA. The present study used osteoporosis model mice to investigate the effects of DHNA on bone remodeling.

METHODS

FK506, an immunosuppressant, was used to prepare osteoporosis model mice. Thirty mice were divided into three groups: FK group, FK+DHNA group, and control group. In the FK group, FK506 was administered to induce bone mass reduction. In the FK-DHNA group, FK506 and DHNA were administered concurrently to observe improvements in bone mass reduction. To ascertain systemic and local effects of DHNA, we investigated systemic pathological changes in colon, kidney function and cytokine dynamics, and morphological and organic changes in bone and osteoclast dynamics as assessed by culture experiments.

RESULTS

Compared to the FK group without DHNA, colon damage and kidney dysfunction were milder for FK+DHNA group, and production of inflammatory cytokines (interleukin (IL)-1beta, IL-6 and tumor necrosis factor (TNF)-alpha) was more suppressed. Furthermore, compared to the group without DHNA, histological analyses and radiography showed that bone resorption was suppressed for the DHNA group. Culture experiments using osteoclasts from murine bone marrow showed osteoclast suppression for the DHNA group compared to the group without DHNA.

CONCLUSION

These results show that DHNA has some effects for improving bone mass reduction caused by FK506.

Comparison of Actual Tidal Volume in Neonatal Lung Model Volume Control Ventilation using Three Ventilators

In neonates, small changes in tidal volumes (VT) may lead to complications. Previous studies have shown a significant difference between ventilator-measured tidal volume and tidal volume delivered (actual VT). We evaluated the accuracy of three different ventilators to deliver small VT during volume-controlled ventilation.

We tested Servo 300, 840 ventilator and Evita 4 Neoflow ventilators with lung models simulating normal and injured neonatal lung compliance models. Gas volume delivered from the ventilator into the test circuit (VTV) and actual VT to the test lung were measured using Ventrak respiration monitors at set VT (30 ml). The gas volume increase of the breathing circuit was then calculated.

Tidal volumes of the SV300 and PB840 in both lung models were similar to the set VT and the actual tidal volumes in the injured model (20.7 ml and 19.8 ml, respectively) were significantly less than that in the normal model (27.4 ml and 23.4 ml). PB840 with circuit compliance compensation could not improve the actual VT. VTV of the EV4N in the normal and the injured models (37.8 ml and 46.6 ml) were markedly increased compared with set VT, and actual VT were similar to set VT in the normal and injured model (30.2 ml and 31.9 ml, respectively). EV4N measuring VT close to the lung could match actual VT to almost the same value as the set VT, however the gas volume of the breathing circuit was increased.

If an accurate value for the patient's actual VT is needed, this VT must be measured by a sensor located between the Y-piece and the tracheal tube.

Investigation of the interaction between hydrogen and screw dislocation in silicon by first-principles calculations

The stability of atomic and molecular hydrogen in the vicinity of a screw dislocation in silicon has been investigated using first-principles calculations. The lowest energy configurations are obtained for H atoms located in the dislocation core, suggesting that the segregation of hydrogen is favoured in the dislocation core. It is found that a spontaneous dissociation of H(2) could occur in the dislocation core. Finally, the variation of the interaction energy between hydrogen and the dislocation core as a function of the separation distance has been calculated. There is no sizeable interaction variation for H(2). However, in the case of a single H, an inverse law has been obtained, which can be explained by the anisotropic stress field generated by the insertion of H in the silicon lattice.

Collagenolytic/gelatinolytic enzymes in corneal wound healing

We have documented changes in expression of collagenolytic/gelatinolytic enzymes of the matrix metalloproteinase family (MMP) in healing or ulcerating corneal wounds of rat or rabbit. Correlation of our findings with specific changes in the extracellular matrix of the repair tissue suggests two different roles for the enzymes, MMP-2 and MMP-9. MMP-2 is expressed in undamaged corneal stroma where it may degrade the occasional collagen molecule that becomes damaged. After corneal wounding, expression of this enzyme is increased and much of it appears in the active form. These changes persist for at least seven months, suggesting that MMP-2 is involved in the prolonged process of collagen remodelling in the stromal repair tissue. MMP-9 is expressed in the epithelial layer of repair tissue with a timing suggesting it might participate in controlling resynthesis of the basement membrane. MMP-9 also appears to be involved in degradation of the epithelial basement membrane that precedes corneal ulceration.

Cesarean section and primary pulmonary hypertension: the role of intravenous dexmedetomidine

Primary pulmonary hypertension is a fatal disease that frequently becomes evident in pregnancy. The management of pregnant women with primary pulmonary hypertension poses a number of difficult problems, especially where regional anesthesia is considered to be contraindicated. A 30-year-old woman who developed primary pulmonary hypertension at 23 weeks of pregnancy was transferred to our hospital. Systolic pulmonary artery pressure and plasma brain natriuretic peptide levels were markedly elevated. Nitric oxide inhalation and prostacyclin prevented the progression of cardiac failure and reduced both plasma brain natriuretic peptide and pulmonary artery pressure. Cesarean section was performed at 32 weeks under general anesthesia. A combination of nitric oxide, prostacyclin, nitroglycerin, and dobutamine were administered during surgery. Intravenous dexmedetomidine was specifically used during emergence and recovery from anesthesia. This provided effective pain relief and hemodynamic stability. Throughout the clinical course, brain natriuretic peptide levels was monitored and used as an indicator of cardiac failure.

First case of bacteremia due to chromosome-encoded CfxA3-beta-lactamase-producing Capnocytophaga sputigena in a pediatric patient with acute erythroblastic leukemia

Bacteremia due to Capnocytophaga sputigena occurred in a 4-year and 9-month-old Japanese girl patient with acute erythroblastic leukemia in Shinshu University Hospital, Japan. On her admission to the hospital, she had a temperature of 38.2 degrees C with canker sore. Prior to the commencement of chemotherapy, peripheral blood culture was carried out with the BacT/Alert 3D System ver. 4.00D (bioMerieux Japan Ltd., Tokyo, Japan) using both the PF and the SN bottles. At 48 hrs of incubation, the System showed the positive sign only in the anaerobic SN bottle for bacterial growth. The strain isolated from the SN bottle was morphologically, biochemically, and genetically characterized, and finally identified as Capnocytophaga sputigena. The causative Capnocytophaga sputigena isolate was found to be a beta-lactamase-producer demonstrating to possess cfxA3 gene. The gene responsible for the production of CfxA3-beta-lactamase was proved to be chromosome-encoded, by means of southern hybridization analysis. This was the first case of bacteremia caused by chromosome-encoded CfxA3-beta-lactamase-producing Capnocytophaga sputigena.

Ultrafast photoinduced insulator-ferromagnet transition in the perovskite manganite Gd0.55Sr0.45MnO3

We have investigated the ultrafast spin and charge dynamics in the course of a photoinduced phase transition from an insulator with short-range charge order and orbital order (OO) to a ferromagnetic metal in perovskite-type Gd0.55Sr0.45MnO3. Transient reflectivity changes suggest that the metallic state is formed just after the photoirradiation and decays within approximately 1 ps. The magnetization, however, increases with the time constant of 0.5 ps and decays in approximately 10 ps. The relatively slow increase of the magnetization is attributable to the magnetic-field-induced alignment of ferromagnetic domains in the initially produced metallic state and its slow decay to the partial recovery of the OO.

Extraction of weak transition strengths via the (3He, t) reaction at 420 MeV

Differential cross sections for transitions of known weak strength were measured with the (3He, t) reaction at 420 MeV on targets of 12C, 13C, 18O, 26Mg, 58Ni, 60Ni, 90Zr, 118Sn, 120Sn, and 208Pb. Using these data, it is shown that the proportionalities between strengths and cross sections for this probe follow simple trends as a function of mass number. These trends can be used to confidently determine Gamow-Teller strength distributions in nuclei for which the proportionality cannot be calibrated via beta-decay strengths. Although theoretical calculations in the distorted-wave Born approximation overestimate the data, they allow one to understand the main experimental features and to predict deviations from the simple trends observed in some of the transitions.

Intramedullary hemorrhage caused by arteriovenous malformation: a case of mixed lateral and medial medullary syndrome

A 48-year-old man with no known risk factor for cerebrovascular disease, other than cigarette smoking, experienced the sudden onset of a mixed lateral and medial medullary syndrome. Computed tomography scan failed to show any definite abnormality. Magnetic resonance imaging scans revealed hemorrhage restricted to the left dorsolateral medulla. Angiography showed abnormal arteries originating from the left vertebral artery with small niduses located on the surface of the medulla and contralateral cerebellum. Small brain-stem hemorrhages are a contraindication to thrombolytic or anticoagulant therapy, and therefore must be recognized in the acute stage.

Cementless total hip replacement after previous intertrochanteric valgus osteotomy for advanced osteoarthritis

We present a series of 30 uncemented total hip replacements performed between June 1985 and January 2002 with a mean follow-up of seven years (5 to 20) in 27 patients who had previously undergone a valgus intertrochanteric osteotomy. No further osteotomy was undertaken to enable hip replacement. We used a number of uncemented modular or monoblock femoral components, acetabular components and bearings. The patients were followed up clinically and radiologically. We report 100% survival of the femoral component. One acetabular component was revised at five years post-implantation for aseptic loosening. We noted cortical hypertrophy around the tip of the monoblock stems in six patients. We believe that modular femoral components should be used when undertaking total hip replacement in patients who have previously undergone valgus femoral osteotomy.

Optical control of the magnetic anisotropy of ferromagnetic bilayered manganites

Optical manipulation of the magnetic anisotropy is demonstrated for bilayered manganites, La2-2xSr1+2xMn2O7, by means of femtosecond Kerr-rotation measurements. Upon the photoexcitation on the x=0.32 crystal, the magnetization exhibits the precessional motion for about 1 ns, revealing the directional change of the magnetocrystalline anisotropy from the c axis to the ab plane. This change of the anisotropy induces the nonthermal decrease of the c-axis magnetization component for about 1 ns.

Heart rate variability during high-intensity field exercise in female distance runners

The purposes of this study were to demonstrate the transition of heart rate variability (HRV) during trials in the field and to examine the relationship between peak frequency of high-frequency band (HF) and stride frequency. Ten healthy long-distance college female runners (age 19-21 years) performed a 3000 m realistic time trial. The time-series power spectrum analysis by maximum entropy method was used to evaluate cardiac autonomic nervous activity during the race. Cross-correlation coefficients were calculated to estimate the degree of linear co-ordination between the central peak frequency of HF and stride frequency. Just after starting, the decrease in HF (0.15-1.00 Hz) and a transient increase of low-frequency band (LF)/HF were found. After that, the HF remained at a low level and LF/HF decreased sharply. These findings suggested that the parasympathetic activity was suppressed and sympathetic activity increased just after starting, and the sympathetic activity reached the saturated level according to continuation of high-intensity exercise. In spite of the significant decrease of HRV during trials, peak frequency of HF could be differentiated clearly. The cross-correlation coefficient of peak frequency of HF and stride frequency was from 0.703 to 0.868. This finding indicated that exercise rhythm reflected HRV during high-intensity running in the field.

Enhanced optical magnetoelectric effect in a patterned polar ferrimagnet

A simple method to dramatically enhance the optical magnetoelectric (ME) effect, i.e., nonreciprocal directional birefringence, is proposed and demonstrated for a polar ferrimagnet GaFeO3 as a typical example. We patterned a simple grating with a period of 4 microm on a surface of GaFeO3 crystal and used the diffracted light as a probe. The optical ME modulation signal for the Bragg spot of the order n=1 becomes gigantic in the photon energy 1-4 eV and reaches 1-2% of the bare diffracted light intensity in a magnetic field of 500 Oe. This is amplified by more than 3 orders of magnitude compared to that for the reflection of bulk GaFeO3. Fabricating a photonic crystal will make it possible to lead the way for the practical use of the optical ME effect.

Dynamical identification of a threshold instability in Si-doped heterofullerenes

We rationalize the origins of a threshold instability and the mechanism of finite temperature fragmentation in highly Si-doped C(60-m)Si(m) heterofullerenes via a first-principles approach. Cage disruption is driven by enhanced fluctuations of the most internal Si atoms. These are located within fully segregated Si regions neighboring the C-populated part of the cage. The predominance of inner Si atoms over those involved in Si-C bonds marks the transition from thermally stable to unstable C(60-m)Si(m) systems at m = 20.

Positron emission tomography and magnetic resonance imaging in spinocerebellar ataxia type 2: a study of symptomatic and asymptomatic individuals

Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disorder characterized as an expanded CAG trinucleotide repeats in SCA2 gene resulting in abnormal polyglutamine sequence. We used positron emission tomography (PET) and magnetic resonance imaging (MRI) to clarify metabolic and atrophic changes of the brain in two symptomatic and three asymptomatic individuals who were genetically confirmed for SCA2. PET revealed decreased glucose metabolism in both patients and two of the three asymptomatic carriers in the cerebellum, pons, or both. No PET abnormality was found in the remaining one carrier who had only a very mildly expanded CAG repeat. MRI showed cerebellar and/or pontine atrophic changes in both patients and one of three carriers. The present study suggest that hypometabolism and atrophy of the cerebellum and pons may occur years before the clinical onset of SCA2. PET and MRI may be useful in the early detection of subclinical brain changes associated with SCA2.

A case of gain-of-function mutation in calcium-sensing receptor: supplemental hydration is required for renal protection

AIMS

The calcium-sensing receptor (CaSR) regulates the extracellular calcium level, mainly by controlling parathyroid hormon secretion and renal calcium reabsorption. In gain-of-function CaSR mutations, the genetic abnormalities increase CaSR activity leading to the development of such clinical manifestations as hypercalciuric hypocalcemia and hypoparathyroidism. We report a Japanese case of CaSR gain-of-function mutation and represent a therapeutic intervention based on the functional characteristics of CaSR in renal tubule.

METHODS AND RESULTS (CASE)

DNA sequence analysis revealed a heterozygous G to T mutation identified in a 12-year-old Japanese girl presenting with sporadic onset of hypercalciuric hypocalcemia and hypoparathyroidism. The mutation is located in the N-terminal extracellular domain of the CaSR gene, one of the most important parts for the three-dimensional construction of the receptor, resulting in the substitution of phenylalanine for cysteine at amino acid 131 (C131F) in exon 3. Based on the diagnosis of the gain-of-function mutation in the CaSR, oral hydrochlorothiazide administration and supplemental hydration were started in addition to calcium supplementation. The combination therapy of thiazide and supplemental hydration markedly reduced both renal calcium excretion and urinary calcium concentration from 0.4-0.7 to less than 0.1 mg/mg (urinary calcium/creatinine ratio) and from 10-15 to 3-5 mg/dl (urinary calcium concentration), respectively. This therapy stopped the progression of renal calcification during the follow-up period.

CONCLUSION

Supplemental hydration should be considered essential for the following reasons: (1) calcium supplementation activates the CaSR in the kidney and suppresses renal urinary concentrating ability, (2) the thiazide has a diuretic effect, (3) as calcium supplementation increases renal calcium excretion, the supplemental hydration decreases urinary calcium concentration by increasing urinary volume, thereby diminishing the risk of intratubular crystallization of calcium ion.

Modeling the pressure inactivation dynamics of Escherichia coli

Escherichia coli, as a model microorganism, was treated in phosphate-buffered saline under high hydrostatic pressure between 100 and 300 MPa, and the inactivation dynamics was investigated from the viewpoint of predictive microbiology. Inactivation data were curve fitted by typical predictive models: logistic, Gompertz and Weibull functions. Weibull function described the inactivation curve the best. Two parameters of Weibull function were calculated for each holding pressure and their dependence on holding pressure was obtained by interpolation. With the interpolated parameters, inactivation curves were simulated and compared with the experimental data sets.