Gender difference in development of steatohepatitis in p62/Sqstm1 and Nrf2 double-knockout mice

Gender and menopause influence the severity and development manner of nonalcoholic steatohepatitis (NASH). Male p62/Sqstm1 and nuclear factor E2-related factor-2 (p62 and Nrf2) double-knockout (DKO) mice exhibit severe steatohepatitis caused by hyperphagia-induced obesity, overload of lipopolysaccharide (LPS) into the liver, and potentiation of the inflammatory response in Kupffer cells. However, the pathogenetic phenotype of steatohepatitis in female DKO mice remains unknown. Phenotypic changes of steatohepatitis in DKO mice were compared in terms of gender differences. Compared with DKO male mice, DKO female mice exhibited later onset of steatohepatitis with obesity after 30 weeks of age, as well as milder severity of hepatic inflammation and fibrosis. Serum estradiol was higher in female than male mice, with levels increasing up to 30 weeks of age before decreasing until 50 weeks of age (corresponding to the post-menopausal period). Fecal and serum LPS were lower in female mice than male mice, and inflammatory signaling in the liver was attenuated in female compared with male mice. Correlating with LPS levels, the composition of intestinal microbiota in female mice was different from male mice. Gender differences were observed for the development of steatohepatitis in DKO mice. Low-grade inflammatory hit in the liver under in vivo conditions of high estradiol may be attributable to the milder pathological features of steatohepatitis in female mice.

0594 Can a Deep Convolutional Neural Network Extract Diagnostic Information on Obstructive Sleep Apnea from Images?

Introduction

Lateral cephalometric radiography is a simple way to provide craniofacial soft/hard tissue profiles specific for patients with obstructive sleep apnea (OSA) and may thus offer diagnostic information on the disease. We hypothesized that a machine learning technology, a deep convolutional neural network (DCNN), could make it possible to detect OSA based solely on lateral cephalometric radiographs without the need for either large amounts of subjective/laboratory data or skilled analyses.

Methods

In this diagnostic study, a DCNN was developed (n=1,258) and tested (n=131) using data from 1,389 lateral cephalometric radiographs obtained from individuals diagnosed with severe OSA (n=867; apnea hypopnea index >30/hour) or non-OSA (n=522; apnea hypopnea index < 5) at a single center for sleep disorders from March, 2006 to February, 2017. Three kinds of data sets were prepared by changing the area of interest using a single image; original image without any modification (Full Image), image containing a facial profile, upper airway, craniofacial soft/hard tissues, and image containing part of the occipital region (upper left corner of the image; Head Only). A radiologist and an orthodontist also performed a manual cephalometric analysis of the Full Image for comparison. Observers were blinded to the patient groupings. Data analysis was performed from April, 2018 to August, 2019. When the predictive score obtained from the DCNN analysis exceeded the threshold (0.50), the patient was judged to have OSA. The primary outcome was diagnostic accuracy in terms of area under the receiver-operating characteristic curve.

Results

The sensitivity/specificity was 0.87/0.82 for Full Image, 0.88/0.75 for Main Region, 0.71/0.63 for Head Only, and 0.54/0.80 for the manual analysis. The area under the curve was the highest for Main Region (0.92): 0.89 for Full Image, 0.70 for Head Only, and 0.75 for the manual analysis.

Conclusion

A DCNN identified individuals with OSA with high accuracy. This is a useful approach that does not require any laborious analyses in a primary care setting or in remote areas where an initial specialized OSA diagnosis is not feasible.

Support

This study was supported in part by the Japan Society for the Promotion of Science (grant numbers 17K11793, 19K10236).

A compact low-temperature hydrogen ion beam apparatus for in situ physical property measurements

A new compact low-temperature hydrogen ion beam apparatus has been developed for in situ physical property measurements. Introduction of hydrogen can significantly alter the physical properties of materials. Conventional methods such as exposure to H₂ gas are limited to materials having hydrogen sorption. The present method is, in principle, applicable to any material of interest. Our setup provides a facile way to conduct both low-temperature hydrogen ion beam irradiation and in situ electrical resistivity measurements, which enables observation of novel physical properties induced by the low-temperature irradiation. The lowest temperature of 3.8 K was achieved by utilizing a newly designed rotatable radiation shield and a closed-cycle cryostat, which is advantageous for long-time low-temperature experiments for heavy hydrogen doping and in situ analysis. It was found that the resistivity of ZnO largely decreased by hydrogen ion beam irradiation at 50 K. Furthermore, the in situ measurements revealed an unforeseen irreversible thermal hysteresis for resistivity.

Hyperspectroscopic imager for baby fibers

Hyperspectral imaging system for diagnosing digestive diseases was newly developed in order to obtain information on pathology beyond morphology of lesions. In order to guide light reflected from a lesion, a baby fiber, which can be inserted in a forceps channel of the electronic endoscope, was also developed. The performance of the system was evaluated by animal experiment. Obtained hyperspectral data were found to have sufficient quality endurable to practical use. Harmful phenomena to a living body were not observed within the experiment. It was considered from the animal experiment that the present system could be practically used for humans.

Modification of a melanoma discrimination index derived from hyperspectral data: a clinical trial conducted in 2 centers between March 2011 and December 2013

BACKGROUND

The morphology of pigmented skin lesions (PSLs) is predominantly a result of varying concentrations and distributions of pigmented molecules such as melanin and hemoglobin. Based on these differences and the fact that their information is contained in cutaneous spectra, a hyperspectral imager (HSI) for pigmented melanoma and a single discrimination index derived from the resultant hyperspectral data are proposed.

OBJECTIVE

To develop and evaluate a new discrimination index for melanomas, compared to the previous index.

METHODS

A HSI, which is convenient for both patients and clinicians, was newly developed and used in a clinical trial conducted in 2 centers with 80 patients with primary lesions and 17 volunteers between March 2011 and December 2013. There were 24 melanomas and 110 other PSLs. A previously proposed discrimination index was used without modifications. A new index, which emphasized the essential features of melanoma, was proposed, and its performance was examined. For each index, a threshold value was set to minimize the average value of the false positive and false negative fractions. The performances of both indices were compared.

RESULTS

The sensitivity and specificity of the old index were 75% and 97%, respectively, while those of the new index were 96% and 87%.

CONCLUSION

The new index had a higher sensitivity and adequate specificity, indicating that it is more useful than the old index.

Sesquiterpenoids from the Roots of Solanum aethiopicum

, 2001 Three new sesquiterpenoids, lubiminoic acid, epilubiminoic acid and aethione, and six known sesquiterpenoids, solavetivone, 3β-hydroxysolavetivone, 13-hydroxysolavetivone, an-hydro-β-rotunol, epilubimin and lubimin, were isolated from roots of S. aethiopicum L. Their structures were elucidated by spectroscopic data.

Size and Shape Variability in Human Molars during Odontogenesis

Under the patterning cascade model (PCM) of cusp development inspired by developmental genetic studies, it is predicted that the location and the size of later-forming cusps are more variable than those of earlier-forming ones. Here we assessed whether differences in the variability among cusps in total and each particular crown component (enamel-dentin junction [EDJ], outer enamel surface [OES], and cement-enamel junction [CEJ]) could be explained by the PCM, using human maxillary permanent first molars (UM1) and second deciduous molars (um2). Specimens were µCT-scanned, and 3D models of EDJ and OES were reconstructed. Based on these models, landmark-based 3D geometric morphometric analyses were conducted. Size variability in both tooth types was generally consistent with the above prediction, and the differences in size variation among cusps were smaller for the crown components completed in later stages of odontogenesis. With a few exceptions, however, the prediction was unsupported regarding shape variability, and UM1 and um2 showed different patterns. Our findings suggested that the pattern of size variability would be caused by temporal factors such as the order of cusp initiation and the duration from the beginning of mineralization to the completion of crown formation, whereas shape variability may be affected by both topographic and temporal factors.

Development of a new measurement system to detect selectively volatile organic compounds derived from the human body

A new concept expired gas measurement system used double cold-trap method was developed. The system could detect selectively volatile organic compound (VOC) derived from the human body. The gas chromatography (GC) profiles of healthy volunteer's expired gas collected by our system were analyzed. As a result, 60 VOCs were detected from the healthy volunteer's expired gas. We examined 14 VOCs among them further, which could be converted to the concentration from the GC profiles. The concentration of almost VOCs decreased when the subjects inspired purified air compared with the atmosphere. On the other hand, isoprene was almost the same. It was strongly suggested that these VOCs were derived from the human body because the concentration of these VOCs in the atmosphere were nearly zero. Expired gas of two sleep apnea syndrome (SAS) patients were analyzed as preliminary study. As a result of the study, the concentration of some VOCs contained in the expired gas of the SAS patients showed higher value than a healthy controls.

Flow Behavior of Sandwich Injection Molding in Sequential and Simultaneous Injection

The flow behavior of skin and core materials in co-injection molding was investigated to understand the flow patterns that could lead to core breakthrough in sequential and simultaneous injection molding. A spiral-flow mold was used and the core material was loaded with a black master batch to facilitate the monitoring of the core material. PC/ABS blend was used as the skin material and ABS was the core material. It was revealed irrespective of simultaneous injection time, sandwich injection molding display the four flow regions identified earlier i. e. primary injection region, core advance region, core expansion region and core breakthrough region. The flow length of core expansion region lengthened with increasing simultaneous injection time of skin and core material while the overall injection time decreased. It was also observed that the core became thinner and wider with increasing simultaneous injection time.

The Flow Behavior of Core Material and Breakthrough Phenomenon in Sandwich Injection Molding

The processing conditions that exert influence on the occurrence of breakthrough during sandwich injection molding were investigated. A spiral flow mold mounted on a twin-barrel injection machine fitted with a single nozzle was used. The effect of mold cavity thickness and the effects of skin material cylinder temperature on skin material viscosity, melt strength, and drawing ratio were considered. Scanning electron microscopy was used to study the morphology of the skin material at the flow front. It was found that the flow length at core expansion region increased and breakthrough phenomenon was delayed as the thickness of the mold cavity increased. When cylinder temperature is increased, the viscosity is lowered and the flow front of the skin material extends with greater ease when pushed by the core material, thus, a greater core volume can be accommodated. As the flow front progresses, the tendency is that the skin material becomes thinner. Polishing and etching followed by SEM examination of the skin material at the flow front revealed that the skin material is oriented perpendicular to the flow direction and the extent of orientation increases with increasing cylinder temperature. This further supported the observation that the deformation ratio and drawing ratio increased with increasing cylinder temperature.

The Flow Behavior of Core Material and Breakthrough Phenomenon in Sandwich Injection Molding

The processing variables that control the occurrence of breakthrough phenomenon in sandwich injection molding were investigated. Particular attention was paid to the conditions that would yield an optimum sandwich molded part. The effects of variation of core volume ratio that would yield optimum core shot size, injection speed and the skin/core viscosity ratio were examined. The flow morphology at the various stages of flow was also explored. The study was conducted with a bar-flow mold mounted on a twin-barrel injection machine fitted with a common nozzle. It was noted that the core material flow distance depends on the core cylinder screw metering position (core shot size). At the stage at which the core material completely penetrated through the skin material (breakthrough), four distinct regions of flow could be identified. The flow distance of the core material is controlled by the injection speed of the core material while the injection speed of the skin material is of little significance. In order to increase the flow distance of the core material, it is effective to increase the core material injection speed albeit limited by an optimum value of screw metering position. It was found that the flow distance of the core material was longer when the core material viscosity was lower than that of the skin material but breakthrough occurred much earlier so core volume is limited. Breakthrough failed to occur when the viscosity of the core material was higher than that of the skin material. It was found that optimum core volume and core distribution occurred when skin/core viscosities were intermediate. The morphology of the skin material leading to breakthrough was also analyzed.

Melanoma screening system using hyperspectral imager attached to imaging fiberscope

Early detection and proper excision of the primary lesions of melanoma are crucial for reducing melanoma-related deaths. In order to support the early detection of melanoma, melanoma screening systems have been extensively studied and developed. Recently we have proposed a melanoma discrimination index derived from hyperspectral data (HSD) in the visible-near infrared wavelength region. The index represents variegation in spectra over a lesion and works well in discriminating melanoma from other pigmented lesions. However the previous hyperspectral imager did not have an enough allowance for measurement of lesions. To overcome the problem with it, we have developed a hyperspectral imager attached to imaging fiberscope. This equipment has been able to accumulate HSD in a view field of φ40 mm within about 10 seconds, from which the above-mentioned melanoma discrimination index has been calculated. Performance of the system has been studied in nine cases of melanoma and 18 cases of non-melanoma, obtained from patients and volunteers, all of whom were Japanese. The index has achieved a sensitivity of 100 % and a specificity of 94.4 %.

Grain Growth Behavior During Microwave Annealing of Silicon Nitride

A comparative study of grain growth behavior in silicon nitride under conventional and microwave annealing is presented. Microwave annealed specimens showed a faster growth rate as indicated by the quantitative microstructural analysis. The phenomenon was used in combination with seeding techniques to develop a silicon nitride exhibiting a bi-modal microstructure. Microwave annealing was carried out using a microwave radiation frequency of 28 GHz.

Identification of QTLs that control clubroot resistance in Brassica oleracea and comparative analysis of clubroot resistance genes between B. rapa and B. oleracea

To perform comparative studies of CR (clubroot resistance) loci in Brassica oleracea and Brassica rapa and to develop marker-assisted selection in B. oleracea, we constructed a B. oleracea map, including specific markers linked to CR genes of B. rapa. We also analyzed CR-QTLs using the mean phenotypes of F(3) progenies from the cross of a resistant double-haploid line (Anju) with a susceptible double-haploid line (GC). In the nine linkage groups obtained (O1-O9), the major QTL, pb-Bo(Anju)1, was derived from Anju with a maximum LOD score (13.7) in O2. The QTL (LOD 5.1) located in O5, pb-Bo(GC)1, was derived from the susceptible GC. Other QTLs with smaller effects were found in O2, O3, and O7. Based on common markers, it was possible to compare our finding CR-QTLs with the B. oleracea CR loci reported by previous authors; pb-Bo(GC)1 may be identical to the CR-QTL reported previously or a different member contained in the same CR gene cluster. In total, the markers linked to seven B. rapa CR genes were mapped on the B. oleracea map. Based on the mapping position and markers of the CR genes, informative comparative studies of CR loci between B. oleracea and B. rapa were performed. Our map discloses specific primer sequences linked to CR genes and includes public SSR markers that will promote pyramiding CR genes in intra- and inter-specific crosses in Brassica crops. Five genes involved in glucosinolates biosynthesis were also mapped, and GSL-BoELONG and GSL-BoPro were found to be linked to the pb-Bo(Anju)1 and Bo(GC)1 loci, respectively. The linkage drag associated with the CR-QTLs is briefly discussed.

Estimation of variability of specific absorption rate with physical description of children exposed to electromagnetic field in the VHF band

Recently, there has been an increasing concern regarding the effects of electromagnetic waves on the health of humans. The safety of radio frequency electromagnetic fields (RF-EMFs) is evaluated by the specific absorption rate (SAR). In recent years, SAR has been estimated by numerical simulation using fine-resolution and anatomically realistic reference whole-body voxel models of people of various ages. The variation in SAR with a change in the physical features of a real person is hardly studied, although every person has different physical features. In this study, in order to estimate the individual variability in SAR of persons, we obtained considerable 3D body shape data from actual three-year-old children and developed several homogeneous models of these children. The variability in SAR of the homogeneous models of three-year-old children for whole-body exposure to RF electromagnetic fields in the very high frequency (VHF) band calculated using the finite-difference time-domain method has been described.

Involvement of Rho kinase in the pathogenesis of acute pulmonary embolism-induced polystyrene microspheres in rats

Acute pulmonary embolism (PE) is a life-threatening disease, and several vasoconstrictors, including endothelin-1 (ET-1), play a key role in vasoconstriction and hypoxemia during the development of PE. Rho kinase is activated by various vasoconstrictors resulting in vascular contraction and remodeling. Recent evidence has revealed an important role of Rho kinase in the pathogenesis of systemic and pulmonary vascular diseases. However, contribution of Rho kinase in PE remains unclear. We thus investigated the role of Rho kinase in the PE rat model induced by intrajugular administration of polystyrene microspheres (mean diameter, 26 microm). At 6 h following the administration of microspheres (1.5 ml/kg), right ventricular systolic pressure (RVSP) was higher in the PE than in the control rats (15.8 +/- 1.6 vs. 32.9 +/- 7.5 mmHg). Arterial oxygen tension was lower (92.3 +/- 12.5 vs. 66.0 +/- 17.7 Torr), and alveolar-arterial difference in oxygen partial pressure was higher (3.9 +/- 3.8 vs. 36.5 +/- 26.9 Torr) in the PE rats. Western blotting analysis revealed upregulation and downregulation in expression of vascular cell adhesion molecule-1 and endothelial nitric oxide synthase in lungs from the PE rats, respectively, and radioimmunoassay demonstrated an increase in plasma ET-1 levels. Lung Rho kinase alpha expression was greater in the PE rats. At 5 h following administration of microspheres (0.75 ml/kg), intravenous Rho kinase inhibitors HA1077 and Y27632 (3 mg/kg each) attenuated elevation of RVSP (22.0 +/- 3.7, 17.1 +/- 3.2, 14.3 +/- 2.6 mmHg, PE, PE+HA1077, PE+Y27632) and the severity of hypoxemia (66.3 +/- 16.2, 94.9 +/- 23.0, 89.1 +/- 8.5 Torr, PE, PE+HA1077, PE+Y27632) in the PE rats. These results suggest that pulmonary endothelial dysfunction and activation of Rho kinase may contribute to the potentiation of vasoconstriction and hypoxemia in the PE rats.

Gadolinium-enhanced three-dimensional magnetization-prepared rapid gradient-echo (3D MP-RAGE) imaging is superior to spin-echo imaging in delineating brain metastases

BACKGROUND

Precisely defining the number and location of brain metastases is very important for establishing a treatment strategy for malignancies. Although magnetic resonance imaging (MRI) is now considered the best modality, various improvements in sequences are still being made.

PURPOSE

To prospectively compare the diagnostic ability of three-dimensional, magnetization-prepared rapid gradient-echo (3D MP-RAGE) imaging in detecting metastatic brain tumors, with that of two-dimensional spin-echo (2D SE) T1-weighted imaging.

MATERIAL AND METHODS

A total of 123 examinations were included in this study, and 119 examinations from 88 patients with known malignancies were analyzed. All patients underwent T1- and T2-weighted 2D SE transverse imaging, followed by gadolinium-enhanced T1-weighted transverse and coronal 2D SE imaging and 3D MP-RAGE transverse imaging. Four radiologists interpreted the images to compare the accuracy and the time required for interpretation for each imaging.

RESULTS

3D MP-RAGE imaging was significantly better than 2D SE imaging for detecting metastatic brain lesions, regardless of the readers' experience. The sensitivities of the 3D MP-RAGE and 2D SE imaging for all observers were 0.81 vs. 0.80 (P>0.05), specificities were 0.93 vs. 0.87 (P<0.05), positive predictive values were 0.92 vs. 0.86 (P<0.05), negative predictive values were 0.78 vs. 0.75 (P>0.05), and accuracies were 0.84 vs. 0.78 (P<0.05), respectively. There was no significant difference in the time required for image interpretation between the two modalities (15.6+/-4.0 vs. 15.4+/-4.1 min).

CONCLUSION

3D MP-RAGE imaging proved superior to 2D SE imaging in the detection of brain metastases.

Dienogest, a selective progestin, reduces plasma estradiol level through induction of apoptosis of granulosa cells in the ovarian dominant follicle without follicle-stimulating hormone suppression in monkeys

Dienogest is a selective progestin that has been shown to arrest ovarian follicular development in women, without affecting gonadotropin secretion. As luteal progesterone or exogeneous progestins are known to suppress ovarian folliculogenesis via the inhibition of gonadotropin secretion, this action of dienogest on ovaries seems to be unique. To examine the underlying mechanism of the antifolliculogenic effect of dienogest, female cynomolgus monkeys were treated with a single oral dose of 0.1 mg/kg dienogest on day 7 of the menstrual cycle. Plasma FSH, estradiol (E2), and progesterone levels were measured up to 15 days after dosing. In an additional experiment, ovaries were excised 24 h after dosing for histological examinations. As a result, plasma E2 level declined within 24 h after dosing, while dienogest did not decreased FSH level prior to E2 decline. After decline of E2 level, the low level of E2 was sustained for more than 11 days. It is considered that a single oral dose of dienogest induced atresia of the dominant follicle. In the histological examination, two out of three animals showed decline in E2 level. The ovarian dominant follicles from these animals showed apoptotic changes in granulosa cells with scattered aromatase expression within 24 h after dosing. These results indicate that the induction of atresia of the ovarian dominant follicle by direct action would be a possible mechanism of dienogest to inhibit plasma E2 level.

An anatomically realistic voxel model of the pregnant woman and numerical dosimetry for a whole-body exposure to RF electromagnetic fields

The numerical dosimetry of pregnant women is one of the most important issues in electromagnetic-field safety. We have recently developed a whole-body numerical female model of an adult Japanese (non-pregnant) average figure. Therefore, a new fetus model including inherent tissues of pregnant women was constructed based on abdominal MRI data of a 7-month pregnant woman. A whole-body pregnant woman model was developed by combining the new fetus and the female models. The anatomical details of the developed pregnant woman model and basic SAR characteristics for whole-body exposure to RF electromagnetic fields are demonstrated.

Anatomically realistic reference models of pregnant women for gestation ages of 13, 18, and 26 weeks

The safety of a human body exposed to radio-frequency (RF) electromagnetic fields (EMFs) has become important today. In recent times, conducting numerical dosimetry on the mother and the fetus during pregnancy has become a particularly important issue. This paper outlines the development of pregnant woman models that were adjusted to the reference values of physiological characteristics of maternal tissues in pregnant women for gestation ages of 13, 18, and 26 weeks The models are composed of voxels of 2 x 2 x 2 mm(3), and there are 56 tissue types. The basic specific absorption rate (SAR) characteristics in the pregnant woman models for whole-body exposure to RF electromagnetic fields that were calculated using the finite-difference time-domain (FDTD) method are described here.

Relation between hematocrit and optical density in pulse oximetry -In vitro study with Waseda mock circulatory system-

Optical properties of living tissues have not been well established even today, and bioopticinstrumentations have to be based on empirical formulae. In order to examine optical properties of the tissue having pulsating blood perfusion, we investigated the relation between optical density (defined as O.D.) of whole blood and hematocrit by transmission spectrophotometry. We used Waseda mock circulatory system that simulates blood circulation in the tissue. It was found that with increasing light path length, O.D. per unit light path length due to scattering and absorption effect, tended to become constant in each hematocrit. For wavelengths of 660, 805 and 940 nm, the relations between O.D. of whole blood and hematocrit predicted by Twersky's equation, Loewinger's equation and photon diffusion equation fitted to the data obtained. Meanwhile, for 1300 nm, the relation predicted by Loewinger's equation gave the best fit to the data.

Development of a small wireless position sensor for medical capsule devices

Medical capsule devices such as video capsule endoscopes are finding increasing use in clinical applications. At present, technologies capable of measuring capsule position in the digestive tract have not yet been established. The present study aims to develop a small wireless position sensor capable of measuring capsule position based on the phenomenon of mutual induction. Currents into primary coils are adjusted to maintain electromotive force induced in secondary coils at a constant level. Electromotive forces induced in the secondary coils are modulated to FM signals using an astable multivibrator, and the signals are passed directly through living tissue at low current and then demodulated by detectors on the surface of the body. A prototype wireless sensor was developed and evaluated in vitro. The sensor was capable of accurately measuring capsule position up to 500 (mm) from the primary coils with an accuracy of 5 (mm). Miniaturization of the sensor is necessary for commercialization.

Development of noninvasive tonometer using resonance phenomenon

A tonometer is used to measure ocular pressure either by shooting a short blast of compressed air onto the cornea or by applying pressure directly to the cornea. At present, the tonometer is the primary instrument available for measuring ocular pressure. However, measuring ocular pressure by such means can either frighten or injure the patient. We propose an improved method of measuring ocular pressure in which the tonometer is applied over the patient's closed eyelid for several seconds. The sensor part of the newly developed tonometer contains a bimorph type transducer and weighs only 28.7 (g). When the sensor is placed on the eyelid and the transducer is vibrated by altering the applied voltage, the current flowing through the transducer changes in relation to the ocular pressure. Ocular pressure can thus be determined based on the current flowing through the system. During measurement, patients are generally unaware of the vibrations of the sensor and report no pain.

Effect of pH and hydration on the normal and lateral interaction forces between alumina surfaces

Interaction forces between alumina surfaces were measured using an AFM-colloid probe method at different pHs. For an alpha-alumina-sapphire system at acidic pH, the force curve exhibited a well-defined repulsive barrier and an attractive minimum. At basic pH, the interactive force was repulsive at all separations with no primary minimum. Lateral force measurements under the same conditions showed that frictional forces were nearly an order of magnitude smaller at basic pH than those observed at acidic pH. This behavior was attributed to the hydration of the alumina surface. Normal and lateral force measurements with the strongly hydrated rho-alumina surfaces supported these findings.

Ca2+ Channel Currents Inhibited by Serum from Select Patients with Guillain-Barré Syndrome

We performed an electrophysiological study demonstrating inhibition of spontaneous muscle action potentials within a coculture of rat muscle and spinal cord by exposure to serum, as well as purified IgG, from patients with the acute motor axonal neuropathy (AMAN) variant of Guillain-Barré syndrome (GBS). However, exposure to serum from two patients with the acute inflammatory demyelinating polyneuropathy (AIDP) form of GBS had no effect. Using a whole-cell recording technique, we then investigated the effects of serum and purified IgG from patients with GBS on voltage-dependent calcium channel (VDCC) currents in nerve growth factor-differentiated PC12 cells. Serum from patients with GBS (AMAN) inhibited VDCC currents in PC12 cells, which was fully reversible by washing with the bath solution. Similarly, purified IgG from the serum of two patients with GBS (AMAN) also inhibited VDCC currents in PC12 cells. In contrast, sera from patients with AIDP and healthy volunteers did not affect VDCC currents in PC12 cells. These results suggest that muscle weakness in some patients with GBS might be induced by inhibition of Ca2+ channel currents within motor nerve terminals.

Choroidal blood flow in the foveal region in eyes with rhegmatogenous retinal detachment and scleral buckling procedures

AIMS

To investigate changes in choroidal blood flow (ChBF) in the foveal region of the human eye with rhegmatogenous retinal detachment induced by scleral buckling.

METHODS

ChBF was measured in the foveal region using laser Doppler flowmetry in patients with a rhegmatogenous retinal detachment and no macular involvement before and after scleral buckling. The ChBF ratio was evaluated (ChBF of the affected eye to ChBF of the fellow control eye) to minimise individual variations.

RESULTS

Retinal reattachment was confirmed by 2 weeks after scleral buckling in all patients. The ChBF in the foveal region of the affected eyes did not differ from the fellow eyes before scleral buckling. The ChBF ratio significantly (p<0.05) decreased 2 and 4 weeks after scleral buckling compared with that before scleral buckling and returned to baseline 12 weeks after scleral buckling.

CONCLUSIONS

The results suggest that ChBF in the foveal region transiently decreases after scleral buckling and recovers to the baseline level within 12 weeks in patients with a retinal detachment and no macular involvement.

Diffusion tensor feature in vasogenic brain edema in cats

We investigated the correlation between the changes in diffusion tensor magnetic resonance imaging, regional water content, and tissue ultrastructure after vasogenic brain edema induced by cortical cold lesioning. In this cat model, E3 in the white matter was dominantly increased while fractional anisotropy (FA) was significantly decreased 8 hours after cortical cold lesioning. This finding indicates that water diffusion in the cortical white matter mainly increased perpendicularly rather than parallel to the direction of the nerve fibers. Additionally, in the area where edema is mild or moderate (tissues with water content of 65% to 75%), FA in the chronic phase was significantly lower than that in the acute phase. Histological examination demonstrated disordered arrangement of nerve fibers, highly dissociated neuronal fibers due to extracellular accumulation of protein rich-fluid, and enlarged interfiber spaces in the acute phase.

Pallidal high-frequency deep brain stimulation for camptocormia: an experience of three cases

INTRODUCTION

The term "camptocormia" describes a forward-flexed posture. It is a condition characterized by severe frontal flexion of the trunk. Recently, camptocormia has been regarded as a form of abdominal segmental dystonia. Deep brain stimulation (DBS) is a promising therapeutic approach to various types of movement disorders. The authors report the neurological effects of DBS to the bilateral globus pallidum (GPi) in three cases of disabling camptocormia.

METHODS

Of the 36 patients with dystonia, three had symptoms similar to that of camptocormia, and all of these patients underwent GPi-DBS. The site of DBS electrode placement was verified by magnetic resonance imaging (MRI). The Burke Fahn and Marsden dystonia rating scale (BFMDRS) was employed to evaluate the severity of dystonic symptoms preoperatively and postoperatively.

RESULTS

Significant functional improvement following GPi-DBS was noted in the majority of dystonia cases. At a follow-up observation after more than six months, the overall improvement rate was 71.2 +/- 27.0%, in all dystonia cases who underwent the GPi-DBS. In contrast, the improvement rate of the three camptocormia cases was 92.2 +/- 5.3%. It was confirmed that the improvement rate for camptocormia was much higher than for other types of dystonia.

CONCLUSION

According to our experience, a patient with a forward-bent dystonic posture indicative of camptocormia is a good candidate for GPi-DBS. The findings of this study add further support to GPi-DBS as an effective treatment for dystonia, and provide the information on predictors of a good outcome.

Serum prorenin levels and diabetic retinopathy in type 2 diabetes: new method to measure serum level of prorenin using antibody activating direct kinetic assay

AIM

To investigate the serum levels of prorenin and its correlation with the severity of diabetic retinopathy (DR).

METHODS

248 patients with diabetes and 108 control subjects were divided into four groups: no-DR (n = 146), no proliferative diabetic retinopathy (no-PDR) (n = 78), PDR (n = 24), and controls (n = 108). Serum levels of prorenin from all subjects were measured using the new antibody activating direct kinetic (AAD-PR) assay. The serum prorenin levels were compared among the groups.

RESULTS

The serum levels of prorenin in the control, no-DR, no-PDR, and PDR groups, respectively, were 109.1 (66.1), 194.6 (160.4), 271.5 (220.3), and 428.4 (358.4) pg/ml (mean (SD)). Prorenin in the PDR group was remarkably high compared with the control and no-DR groups (p<0.0001) and with the no-PDR group (p = 0.002). Serum levels of prorenin increased with increasingly severe retinopathy. No correlation was found between the prorenin level and the duration of disease or HbA(1c).

CONCLUSIONS

The serum levels of prorenin in patients with PDR were found to be markedly high using the AAD-PR assay. Increased levels of prorenin in diabetes may have an important role in the pathogenesis of DR.

Peroxynitrite decomposition catalyst, FP15, and poly(ADP-ribose) polymerase inhibitor, PJ34, inhibit leukocyte entrapment in the retinal microcirculation of diabetic rats

PURPOSE

Oxidative and nitrosative stress and activation of poly(ADP ribose) polymerase (PARP) play a role in the pathogenesis of diabetic complications. We evaluated the effectiveness of the peroxynitrite decomposition catalyst, FP15, and the PARP inhibitor, PJ34, in the treatment of leukocyte entrapment in the retinal microcirculation of diabetic rats.

METHODS

Diabetes was induced in rats by intraperitoneal injection of 60 mg/kg of streptozotocin. Rats were divided into four groups: controls; untreated diabetes; diabetes treated with FP15 (10 mg/kg oral gavage twice daily) and diabetes treated with PJ34 (10 mg/kg oral gavage twice daily). All experiments were performed 4 weeks after initiation of treatment. Leukocyte entrapment in the retinal microcirculation was quantitatively evaluated in vivo with acridine orange digital fluorography.

RESULTS

The density of leukocytes trapped in the retinal microcirculation 30 minutes after dye injection was significantly greater in untreated diabetes (32.1 +/- 4.7 cells/mm2) than in controls (11.3 +/- 4.5 cells/mm2) (p < 0.05). Compared with untreated diabetes, the density of trapped leukocytes significantly decreased in diabetes treated with FP15 (14.5 +/- 5.1 cells/mm2) (p < 0.0001) and diabetes treated with PJ34 (24.1 +/- 4.2 cells/mm2) (p < 0.05).

CONCLUSIONS

Treatment with FP15 and PJ34 decreased enhanced leukocyte entrapment in the retinal microcirculation during the early diabetic period. The current study suggests a role for peroxynitrite production and for PARP activation in the pathogenesis of retinal microvascular leukostasis in early diabetes.

Effect of haemodialysis on retinal circulation in patients with end stage renal disease

AIMS

To investigate the effect of haemodialysis on retinal circulation in patients with end stage renal disease (ESRD).

METHOD

Seventeen consecutive patients with ESRD were recruited into the study. The authors simultaneously measured changes in vessel diameter and blood velocity and calculated the retinal blood flow (RBF) in the retinal veins in patients with ESRD before and after haemodialysis using a laser Doppler velocimetry system. In addition, the relations between the changes in systemic and retinal circulatory parameters were examined.

RESULTS

There was a group averaged increase in vessel diameter (p = 0.003) after haemodialysis. However, the blood velocity and RBF values obtained after haemodialysis were not significantly different from those before haemodialysis (p = 0.66 and p = 0.63, respectively). The changes in vessel diameter were negatively (r = -0.549, p = 0.02) correlated with the change in MABP, but the changes in blood velocity and RBF were positively correlated with the change in MABP (r = 0.683, p<0.002 and r = 0.589, p<0.01, respectively). The change in RBF was also inversely correlated with the increase in haematocrit (r = -0.693, p<0.002) and the amount of fluid removed (r = -0.597, p<0.01).

CONCLUSION

The results indicate that haemodialysis and the associated changes in systemic circulatory parameters may affect the retinal circulation in patients with ESRD.

Alteration of choroidal circulation in the foveal region in patients with type 2 diabetes

AIM

To investigate changes in choroidal blood flow (CBF) in the foveal region in patients with type 2 diabetes.

METHODS

Laser Doppler flowmetry was used to determine the CBF in the foveal region in 70 patients with type 2 diabetes and 36 age and sex matched healthy subjects (control group). The patients were classified into three groups: 33 patients (33 eyes) with no diabetic retinopathy (NDR), 20 patients (20 eyes) with non-proliferative diabetic retinopathy and no macular oedema (NPDR/MO-), and 17 patients (17 eyes) with NPDR and MO (NPDR/MO+). Optical coherence tomography was also used to measure the foveal thickness.

RESULTS

The group averaged CBF values were 13.5 (4.9), 9.4 (2.5), 10.8 (4.8), and 5.6 (2.0) (arbitrary units) in the control, NDR, NPDR/MO-, and NPDR/MO+ groups, respectively. The group averaged CBF values in the NDR group decreased (30.2%; p<0.01) compared with the control group. The average CBF value in the NPDR/MO+ group was also significantly lower (48.2%; p<0.01) compared with that in the NPDR/MO- group.

CONCLUSION

The CBF in the foveal region significantly decreases in patients with diabetes, especially those with macular oedema.

Isolation and characterization of psychrophilic yeasts producing cold-adapted pectinolytic enzymes

AIMS

The present study was conducted to screen for psychrophilic yeasts that are able to degrade pectin compounds at low temperature, and to examine the cold-active pectinolytic enzymes produced by the isolated psychrophilic yeasts.

METHODS AND RESULTS

Psychrophilic yeasts, which grow on pectin as a sole carbon source, pectinolytic-psychrophilic yeast (PPY) strains PPY-3, 4, 5 and 6, were isolated from soil from Abashiri (Hokkaido, Japan). The sequences of 28S rDNA D1/D2 of strains PPY-3 and 4 indicated a taxonomic affiliation to Cryptococcus cylindricus and Mrakia frigida, respectively, strains PPY-5 and 6 belonged to Cystofilobasidium capitatum. The isolated strains were able to grow on pectin at below 5 degrees C, and showed the activities of several cold-active pectinolytic enzymes.

CONCLUSION

The findings of this study indicate the possibility that the isolated strains produce novel pectinolytic enzymes that are able to degrade pectin compounds at low temperature.

SIGNIFICANCE AND IMPACT OF THE STUDY

It is possible that the cold-active pectinolytic enzymes from the isolated strains can be applied to the food industry, e.g. the clarification of fruit juice below 5 degrees C.

Recovery of apparent diffusion coefficient after embolic stroke does not signify complete salvage of post-ischemic neuronal tissue

BACKGROUND AND PURPOSE

It has been shown in previous studies that recovery of apparent diffusion coefficient (ADC) of water is not necessarily associated with a reversal of tissue damage. We examined the relationships between temporal ADC change and histological outcome after embolic stroke in rat using an experimental MRI scanner.

SUBJECTS AND METHODS

Male Wistar rats underwent embolization of the right middle cerebral artery with autologous clot. ADC and relative cerebral blood flow (rCBF) were measured consecutively for 3 hours after embolization. The brains were prepared for histological examination.

RESULTS

Transient decline of ADC was observed during the initial 2 hours after embolization. In these areas, serial rCBF measurement revealed incomplete recovery. In some other areas, ADC decrease without rCBF recovery was observed during 3 hours postischemia. Histological examination revealed infarction in areas with persistent ADC decrease. Scattered neuronal death was noticeable in areas with a transient--in some areas less than 0.5 hour--ADC decrease.

CONCLUSION

Consecutive MRI analysis demonstrated postischemic transient ADC decrease in an embolic stroke model of rat. The normalization of ADC does not signify normalization of postischemic tissue, since the areas often evolve postischemic neuronal death at a later time.

PET neuroreceptor imaging as predictor of severe cerebral ischemic insult

Measurement of the adenosine A1 receptor (A1-R) with positron emission tomography (PET) using a newly developed positron ligand, [1-methyl-11C]8-dicyclopropylmethyl-1-methyl-3-propylxanthine (MPDX). were performed in a cat middle cerebral artery (MCA) occlusion and reperfusion. Eighteen adult cats underwent PET measurement of; 1) cerebral blood flow (CBF). 2) A1-R, 3) central benzodiazepine receptor (BDZ-R) and 4) glucose metabolism with 15O labeled water, MPDX, 11C-flumazenil (FMZ) and 18F-fluorodeoxyglucose (FDG), respectively. The CBF, A1-R, BDZ-R and FDG uptake were serially measured after 60 min occlusion of MCA in this order. MPDX binding and FMZ binding, but not CBF and FDG uptake, were significantly reduced in the groups with severer ischemic insult than in the groups with no or milder insults. Of the two receptor ligands, the reduction rate of the MPDX binding to A1-Rs was larger in a group that caused fatal ischemic insult. The newly developed PET in vivo imaging technique using MPDX was suitable in evaluating the function of adenosine and A1-Rs in relation to cerebral ischemia.

Features of abnormal choroidal circulation in central serous chorioretinopathy

AIMS

To evaluate abnormalities in the choroidal circulation in cases of central serous chorioretinopathy (CSC).

METHODS

A complete clinical ophthalmological examination was performed using simultaneous fluorescein and indocyanine green (ICG) angiography with a confocal scanning laser ophthalmoscopy and the digital images analysed in 36 consecutive patients with acute CSC. To quantify the choroidal circulation, the foveal choroidal blood flow was measured in 11 patients using laser Doppler flowmetry.

RESULTS

Fluorescein angiography showed focal leakage from the retinal pigment epithelium in all patients. ICG angiography revealed delays in arterial filling in 27 eyes (75%), and fluorescein angiography showed small hypofluorescent points around the leakage in 27 eyes (75%). Abnormal choroidal hyperfluorescence was observed in 30 eyes (83%). The choroidal blood flow in eyes with CSC was 45% lower than in fellow eyes (p<0.01).

CONCLUSION

Decreased choroidal blood flow in CSC was demonstrated for the first time. The decreased choroidal blood flow might be correlated with the small, localised hypofluorescent areas, which may indicate non-perfused areas of the choriocapillaris that are frequently seen during ICG angiography.

Inhibitory effect of losartan, an AT1 angiotensin II receptor antagonist, on increased leucocyte entrapment in retinal microcirculation of diabetic rats

BACKGROUND

The effectiveness of losartan for the treatment of leucocyte entrapment in the retinal microcirculation of diabetic rats was evaluated quantitatively.

METHODS

After diabetes was induced by injection of streptozotocin (STZ), the rats were divided into two subgroups. The first subgroup (n = 6), received no medications; the second subgroup (n = 6) was given fresh drinking water supplemented with losartan (5 mg/kg/day) for 4 weeks. Six rats that were not injected with STZ or given medications served as controls. 4 weeks after intervention, leucocyte dynamics in the retina were observed using acridine orange digital fluorography. Leucocyte entrapment in the retina was compared among the three groups.

RESULTS

In the untreated diabetic rats, the number of trapped leucocytes (6.1 (SD 1.4) cells/mm(2)) increased significantly compared with control rats (2.8 (1.2) cells/mm(2); p = 0.005) and diabetic rats treated with losartan (3.1 (0.9) cells/mm(2); p = 0.0002).

CONCLUSIONS

Losartan, an AT1 angiotensin II receptor antagonist, inhibited increased leucocyte entrapment in the diabetic retina. The authors demonstrated that losartan may have therapeutic efficacy in preventing development of diabetic retinopathy. Further clinical studies of the effect of the angiotensin receptor antagonist on preventing development of diabetic retinopathy are needed.

A case of refractory hypothyroidism requiring daily intravenous thyroxine

Most patients with hypothyroidism respond to administration of oral thyroxine at a maintenance dose of 50-175 micrograms/day. This is the first documented patient with post-operative hypothyroidism who required about 10 times the standard dose of thyroxine, and whose symptoms only resolved when intravenous thyroxine was administered daily. Our findings support the benefits of daily intravenous therapy with thyroxine in this case.