Cluster Analysis of Subjective Shoulder Stiffness and Muscle Hardness: Associations with Central Sensitization-Related Symptoms

Background and Objectives: Understanding the relationships between subjective shoulder stiffness, muscle hardness, and various factors is crucial. Our cross-sectional study identified subgroups of shoulder stiffness based on symptoms and muscle hardness and investigated associated factors. Materials and Methods: measures included subjective stiffness, pain, muscle hardness, and factors like physical and psychological conditions, pressure pain threshold, postural alignment, heart rate variability, and electroencephalography in 40 healthy young individuals. Results: Three clusters were identified: Cluster 1 with high stiffness, pain, and muscle hardness; Cluster 2 with low stiffness and pain but high muscle hardness; and Cluster 3 with low levels of all factors. Cluster 1 had significantly higher central sensitization-related symptoms (CSS) scores than Cluster 2. Subjective stiffness is positively correlated with psychological factors. Conclusions: our results suggest that CSS impacts subjective symptom severity among individuals with similar shoulder muscle hardness.

Predicting habitual water intake from lifestyle questions

OBJECTIVE

Previous studies have used selective recall and descriptive dietary record methods, requiring considerable effort for assessing food and water intake. This study created a simplified lifestyle questionnaire to predict habitual water intake (SQW), accurately and quickly assessing the habitual water intake. We also evaluated the validity using descriptive dietary records as a cross-sectional study.

SUBJECTS AND METHODS

First, we used crowdsourcing and machine learning to collect data, predict water intake records, and create questionnaires. We collected 305 lifestyle-related questions as predictor variables and selective recall methods for assessing water intake as an outcome variable. Random forests were used for the machine learning models because of their interpretability and accurate estimation. Random forest and single regression correlation analysis were augmented by the synthetic minority oversampling that trained the model. We separated the data by sex and evaluated our model using unseen hold-out testing data, predicting the individual and overall habitual water intake from various sources, including non-alcoholic beverages, alcohol, and food.

RESULTS

We found a 0.60 Spearman's correlation coefficient for total water intake between the predicted and the selective recall method values, reflecting the target value to be achieved. This question set was then used for feasibility tests. The descriptive dietary record method helped to obtain a ground-truth value. We categorized the data by gender, season, and source: non-alcoholic beverages, alcohol, food, and total water intake, and the correlation was confirmed. Consequently, our results showed a Pearson's correlation coefficient of 0.50 for total water intake between the predicted and the selective recall method values.

CONCLUSIONS

We hypothesize that dissemination of SQW can lead to better health management by easily determining the habitual water intake.

The Impact of Stretching Intensities on Neural and Autonomic Responses: Implications for Relaxation

Stretching is an effective exercise for increasing body flexibility and pain relief. This study investigates the relationship between stretching intensity and relaxation effects, focusing on brainwaves and autonomic nervous system (ANS) activity. We used a crossover design with low- and high-intensity conditions to elucidate the impact of varying stretching intensities on neural activity associated with relaxation in 19 healthy young adults. Participants completed mood questionnaires. Electroencephalography (EEG) and plethysmography measurements were also obtained before, during, and after stretching sessions. The hamstring muscle was targeted for stretching, with intensity conditions based on the Point of Discomfort. Data analysis included wavelet analysis for EEG, plethysmography data, and repeated-measures ANOVA to differentiate mood, ANS activity, and brain activity related to stretching intensity. Results demonstrated no significant differences between ANS and brain activity based on stretching intensity. However, sympathetic nervous activity showed higher activity during the rest phases than in the stretch phases. Regarding brain activity, alpha and beta waves showed higher activity during the rest phases than in the stretch phases. A negative correlation between alpha waves and sympathetic nervous activities was observed in high-intensity conditions. However, a positive correlation between beta waves and parasympathetic nervous activities was found in low-intensity conditions. Our findings suggest that stretching can induce interactions between the ANS and brain activity.

Effects of axial extension on pelvic floor displacement and abdominal muscle activity during a pelvic floor muscle task

BACKGROUND

The effects of axial extension on pelvic floor displacement and abdominal muscle activity during pelvic floor muscle (PFM) exercises are not well known.

OBJECTIVE

To clarify the effect of sitting axial extension on pelvic floor displacement and abdominal muscle activity during a PFM task.

METHODS

Pelvic floor displacement, abdominal muscle activity, and subjective kinesthesia of the PFM were compared between the resting and axial-extended sitting positions during a pelvic floor task in 34 healthy young men.

RESULTS

No significant difference in pelvic floor displacement was observed between the resting and axial extension sitting position. Subjective kinesthesia was significantly easier to perform in axial extension than in resting sitting position during pelvic floor depression. Abdominal oblique muscle activity was higher in axial extension than in resting sitting position during pelvic floor depression. The changes in axial extension were significantly greater in the internal oblique muscles during elevation and in the internal and external oblique muscles during depression than in the lower rectus abdominis muscles.

CONCLUSION

Axial extension in the sitting position does not change pelvic floor displacement during the PFM task. However, axial extension may be effective in facilitating subjective kinesthesia of PFM and in increasing oblique abdominal muscle activity.

Relationship between lumbar spine motor control ability and perceptual awareness during prone hip extension movement in people with low back pain

PURPOSE

The purpose of this study was to clarify the differences in lumbar spine and hip joint motor control ability (MCA) in prone hip extension (PHE) between individuals with and without low back pain (LBP). It also aimed to determine the relationship between lumbar spine and hip joint MCA and lumbar perceptual awareness in individuals with LBP.

METHODS

In total, 78 university students (20 with LBP and 58 without) were included in the study. The MCA of the lumbar spine and hip joint in PHE and perceptual awareness were evaluated. The MCA of the lumbar spine and hip joint was measured using a wearable sensor. Subsequently, a comparison of the MCA of the lumbar spine and hip joints of the participants and the relationship between MCA and lumbar perceptual awareness were examined.

RESULTS

The MCA of the LBP group was higher than that of the non-LBP group in motion on the sagittal plane. In addition, perceptual awareness was negatively correlated with MCA in the sagittal plane in the lumbar spine.

CONCLUSION

People with LBP had higher lumbar spine and hip joint MCA than those without LBP. Perceptual awareness was associated with lumbar spine and hip joint MCA in people with LBP. J. Med. Invest. 69 : 38-44, February, 2022.

Relationships among lumbar hip motion angle, perceptual awareness, and low back pain in young adults

[Purpose] We aimed to examine the relationships among low back pain, lumbar-hip motion angle, and lumbar perceptual awareness in young adults to improve the treatment of low back pain. [Participants and Methods] Data were collected from 36 university students with low back pain. The items included for evaluation were the low back pain intensity (Numeric Rating Scale), disability due to low back pain (Oswestry Low Back Pain Disability Index), lumbar spine and hip motion angles in test movements, and perceptual awareness (Fremantle Back Awareness Questionnaire). The test movements employed included trunk forward bending, trunk back bending, and prone hip extension. The motion angles of the lumbar spine and hip joints were measured using a wearable sensor. [Results] The Numeric Rating Scale was not correlated with the lumbar hip motion angle and perceptual awareness. The Oswestry Low Back Pain Disability Index was correlated with lumbar hip motion angles, at the beginning of trunk forward bending and at maximum trunk backward bending, and with perceptual awareness. [Conclusion] There are relationships among disabilities due to low back pain, lumbar hip motion angles, and perceptual awareness in each test movement; however, they vary depending on the type and angle of the test movement conducted.

Immediate effects of elongation training using an elastic band on the hip abductor muscles

[Purpose] This study investigated the effects of elongation training on the hip abductor muscles in comparison with the effects of general hip abductor training. [Participants and Methods] This study included 39 healthy male university students. The participants were divided into elongation training and general-weighted hip abduction training groups. An elastic band was used for elongation training, and hip abduction exercises were performed with instructions to extend the foot as far as possible to stretch the band. Measurements were taken before and after training, and the surface electromyographic data of the gluteus medius and the tensor fasciae latae were measured during isometric contraction of the hip abductor muscles. The surface electromyogram data were used to calculate integral values and median power frequencies to compare the effects of training. [Results] In comparison with general hip abductor training, elongation training yielded a larger change in the ratio of muscle integral values (gluteus medius/tensor fasciae latae). [Conclusion] Elongation training of the hip abductor muscles was more useful than general training in increasing the activity of the gluteus medius while suppressing the activity of the tensor fasciae latae.

Relationship between trunk muscle strength and trunk muscle mass and thickness using bioelectrical impedance analysis and ultrasound imaging

BACKGROUND

Although trunk muscles are involved in many important functions, evaluating trunk muscle strength is not an easy task. If trunk muscle mass and thickness could be used as indicators of trunk muscle strength, the burden of measurement would be reduced, but the relationship between trunk muscle strength and trunk muscle mass and thickness has not been clarified.

OBJECTIVE

The purpose of this study was to clarify the relationship between trunk muscle strength and trunk muscle mass by bioelectrical impedance analysis and trunk muscle thickness by ultrasound imaging in healthy adults.

METHODS

One hundred and twenty-one healthy university students were included in this study. Trunk flexion/extension muscle strength and trunk muscle mass by bioelectrical impedance analysis, and trunk muscle thickness by ultrasound imaging were measured.

RESULTS

Both trunk flexion strength and trunk extension strength were significantly correlated with trunk muscle mass and oblique and rectus abdominis muscle thickness. Multiple regression analysis showed that trunk extension muscle strength had an independent relationship with trunk muscle mass.

CONCLUSIONS

This study demonstrated that trunk muscle mass or trunk muscle thickness can be used as an alternative means for evaluating trunk muscle strength, making the evaluation of trunk muscles less burdensome.

Intra-rater reliability of measurement of abdominal perimuscular connective tissue thickness on ultrasound images

[Purpose] The thickness of the perimuscular connective tissue (PMCT) reflects muscular atrophy and decreased flexibility that may cause low back pain. However, few studies have used ultrasound imaging to measure PMCT thickness. We aimed to examine and confirm the reliability of ultrasound in measuring the thickness of the PMCT of the abdominal wall muscle. [Participants and Methods] The participants were 38 healthy adult males without chronic back pain. The images were acquired in B mode with the participants in the supine position and the PMCT thickness of the abdominal wall muscle was measured on the images. The intraclass correlation coefficient (ICC) was used to confirm reliability. [Results] The ICC for both within-day and between-day PMCT measurements by ultrasound were 0.7–0.9. The 95% confidence interval ranged from 0.5–0.9. The standard error of measurement (SEM) was 0.02–0.1 mm in the abdominal wall muscle and 0.5 mm in the interrecti distance (IRD). The 95% confidence interval (95% CI) of the minimum detectable change (MDC95) was 0.1–0.3 mm in the abdominal wall muscle and 1.3–1.4 mm in the IRD. [Conclusion] We conducted a study to confirm the reliability of ultrasound-based measurement of PMCT thickness of the abdominal wall muscle, and the ICC results established reliability. However, since the values measured were small (0.02–1.4 mm) and there is a limit to visual observation, it was necessary to measure using computer software.

Relationship Between Lumbar Motor Control Ability and Spinal Curvature in Elderly Individuals

This study aimed to clarify the relationship between spine curvature and the movement pattern/motor control ability of the lumbar and hip joints during prone hip extension in elderly individuals. The participants were 14 elderly people who attended a community health class. We measured the motion angle, motion ratio (movement pattern), and motor control ability of the lumbar and hip joints during prone hip extension. In addition, the lumbar lordosis angle and thoracic kyphosis angle were measured in the standing position. There was no correlation between the spinal curvature in the standing position and the lumbar/hip joint movement pattern and motor control ability during prone hip extension. When evaluating the lumbar spine, it is necessary to perform a comprehensive evaluation by interpreting static evaluations such as spinal alignment or dynamic evaluations such as movement patterns and motor control abilities.

Change in muscle thickness during exercise to stabilize the hip joint against a load in the ventral direction of the femoral head

[Purpose] This study aimed to measure the thickness of the muscles located on the ventral side of the hip joint and to identify the muscles involved in exercise against the load that results in femoral head translation in the ventral direction, which can be used as an index of exercise performance for the prevention and improvement of hip joint disease caused by femoral head translation. [Participants and Methods] The participants were 10 healthy young males. During the measurement task, we asked them to hold a 10 kgf load in the ventral direction to the femoral head in the supine position. We measured the thickness of the gluteus minimus, gluteus medius, tensor fascia latae, and iliopsoas both at rest and during exercise using ultrasonography. [Results] We compared muscle thicknesses at rest and during exercise and found that only the gluteus minimus had significantly lower values during exercise. We also compared the rate of change in muscle thickness and found that the gluteus minimus exhibited significantly higher values than those of the gluteus medius and tensor fasciae latae. [Conclusion] Our study indicates that the gluteus minimus is more involved than the gluteus medius, tensor fasciae latae, and iliopsoas in the exercise for the ventral displacement of the femoral head.

Examination of the intrarater reliability of ultrasound measurements of the thickness of the lumbar and lateral abdominal muscles in the prone position

[Purpose] This study aimed to examine the intrarater reliability when measuring the thickness of the lumbar and lateral abdominal muscles using ultrasound with the participants in the prone position. [Participants and Methods] The participants were 10 healthy adult males without chronic low back pain. The muscle thicknesses of the lumbar multifidus, erector spinae, obliquus externus abdominis, obliquus internus abdominis, and transversus abdominal muscles were measured using ultrasound with the participants in the prone position. [Results] The intraclass correlation coefficients of the within-day and between-day intrarater reliability measurements were 31.1–34.1 mm (lumbar multifidus), 32.0–33.5 mm (erector spinae), 7.4–8.0 mm (obliquus externus abdominis), 9.4–10.4 mm (obliquus internus abdominis), and 2.9–3.4 mm (transversus abdominal). The standard error of measurement and 95% confidence interval of minimal detectable change of the within- and between-day measurements were 0.1–1.2 mm and 0.3–3.4 mm, respectively, for each muscle. [Conclusion] The reliability of measuring the lumbar and lateral abdominal muscles in the prone position using ultrasound was confirmed. It was suggested that measurements during muscle activity and extremity movement are possible when participants are in the prone position.

Subcutaneous Xenotransplantation of Hybrid Artificial Pancreas Encapsulating Pancreatic B Cell Line (MIN6): Functional and Histological Study

The biohybrid artificial pancreas is designed to enclose pancreatic endocrine tissues with a selectively permeable membrane that immunoisolates the graft from the host immune system, allowing those endocrine tissues to survive and control glucose metabolism for an extended period of time. The pancreatic B cell line MIN6 is established from a pancreas B cell tumor occurring in transgenic mice harboring the human insulin promoter gene connected to the SV40 T-antigen hybrid gene. It has been proven that glucose-stimulated insulin secretion in MIN6 cells retains a concentration-dependent response similar to that of normal islets. In this study, we performed the histological and functional examination of three-layer microbeads employing MIN6 cells after subcutaneous xenotransplantation to evaluate this device as bioartificial pancreas. MIN6 cells were microencapsulated in three-layer microbeads formulated with agarose, polystyrene sulfonic acid, polybrene, and carboxymethyl cellulose. Microbeads were xenogenically implanted in the subcutaneous tissue of the back of Lewis rats with streptozotocin-induced diabetes. One week after implantation, microbeads were retrieved and cultured for 24 h before the static incubation. There was no evidence of adhesion to the graft and the fibrosis in the transplantation site as determined by gross visual inspection. Microscopic examination demonstrated that retrieved microbeads maintained normal shape, containing intact MIN6 cells. Histological study showed that these MIN6 cells in the microbeads appeared to be viable without cellular infiltration within or around the microbeads. Immunohistochemical analysis of the microbeads clearly revealed the intense staining of insulin in the cytoplasm of encapsulated MIN6 cells. Insulin productivity of MIN6 cells in the microbeads is strongly suggested to be preserved. In response to 16.7 mM glucose stimulation, static incubation of microbeads 1 wk after implantation caused the 2.3 times increase in insulin secretion seen after 3.3 mM glucose stimulation (84.3 ± 10.0 vs. 37.4 ± 10.7 μU/3 × 106 cells/hr, n = 5 each, p < 0.01). This study demonstrates that three-layer microbeads encapsulating MIN6 cells retain excellent biocompatibility and maintain good insulin secretion even after subcutaneous xenotransplantation, suggesting the possible future clinical application of this unique bioartificial pancreas to subcutaneous xenotransplantation.

Embedded-Culture of Pancreatic β-Cells Derived from Transgenic Mouse Insulinoma as a Potential Source for Xenotransplantation using a Diffusion Chamber

Embedded-culture of pancreatic β-cells derived from a transgenic mouse insulinoma (MIN6 cells) was studied in vitro and in vivo. The MIN6 cells were enmeshed in an agarose-PVMA-collagen matrix for long-term maintenance. The cells formed islet-like cell clusters (ICCs) in the mixed matrix. When 10 mmol/L nicotinamide was added to these cultures the cells secreted insulin in response to various concentrations of glucose, whereas the untreated control cells were unresponsive. Both control and nicotinamide-treated MIN6 cells exhibited normal β-cell function for up to 35 days in the mixed matrix, and the cells were much better preserved with nicotinamide than without it. MIN6 cells were suspended in the mixed matrix with nicotinamide and transferred into diffusion chambers to create a bio-artificial endocrine pancreas (Bio-AEP). In streptozotocine-induced diabetic rats with implanted Bio-AEP but without any immunosuppressants, a return to normoglycaemia was observed for up to 12 wk or more after transplantation. Our results indicate that nicotinamide-treated MIN6 cells embedded in a mixed matrix should be useful for the study of xenotransplantation and the development of a bioartificial endocrine pancreas.

Examinations of factors influencing toe grip strength

[Purpose] This study examined the relationship between toe grip strength and its associated factors by focusing on factors that were suggested to have a relationship with toe grip strength in previous studies, aiming to clarify the factors influencing the toe grip strength of healthy women. [Subjects and Methods] Twelve healthy young women were selected for this study. Their toe grip strength, angular changes in their ankle joint during toe grip, maximum voluntary contraction activities of the rectus femoris, biceps femoris, and tibialis anterior muscles, and the medial head of the gastrocnemius muscles were measured using electromyography. Their toe curl ability, foot-arch height ratio, and weight were also measured. [Results] Multiple regression analysis demonstrated that the predictors of toe grip strength in the resulting model were foot-arch height ratio and the percentage of integrated electromyography (%IEMG) of the tibialis anterior muscle, as the dependent variables. This reveals that women whose tibialis anterior muscle %IEMG values and foot-arch height ratio are high have greater %IEMG values have greater toe grip strength. [Conclusion] These findings suggest a significant relationship between foot-arch height ratio and toe grip strength, with a reciprocal interaction. These findings further indicate that the risk of falls by the elderly could be decreased if toe grip strength were enhanced, by increasing the height of a low foot-arch with the help of an inserted insole.

Comparison of toe grip strength and muscle activities during maximal toe grip strength exertion according to the presence/absence of an ankle immobilization belt

[Purpose] The aim of this study was to compare toe grip strength and muscle activity during toe grip strength exertion according to the presence/absence of an ankle immobilization belt and to examine the relationship between the differences in muscle activity and toe grip strength. [Subjects] The Subjects were 13 healthy young women. [Methods] We measured toe grip strength and muscle activity during toe grip strength exertion in the presence and absence of an ankle immobilization belt using electromyography. Activity in the following leg muscles was recorded: rectus femoris, biceps femoris, medial head of the gastrocnemius, and tibialis anterior. We then calculated the percent integrated electromyography during toe gripping. [Results] Toe grip strength and percent integrated electromyography of the medial head of the gastrocnemius muscle were significantly higher with ankle belt immobilization compared with without ankle belt immobilization. In addition, in the presence of ankle belt immobilization, the percent integrated electromyography of the tibialis anterior muscle and medial head of the gastrocnemius muscle demonstrated a positive correlation with toe grip strength (r = 0.75 and r = 0.65, respectively). [Conclusion] These findings suggest that greater toe grip strength could be exerted in the presence of ankle belt immobilization. The measured values reflect the percent integrated electromyography of the crural muscles. Therefore, it was shown that toe grip strength should be measured in the presence of an immobilization belt.

Kinematic analysis during toe-gripping strength exertion: angular changes in the ankle joint and leg muscle activities

[Purposes] To investigate angular changes in the ankle joint and leg muscle activities during toe-gripping, and to examine the relationship between these changes and toe-gripping strength. [Subjects] Eleven healthy young women were selected. [Methods] We measured the toe-gripping strength, angular changes in the ankle joint, and leg muscle activities of all patients during toe-gripping. [Results] The mean change in the ankle angle in dorsiflexion from a neutral position was 3°, and a positive correlation was observed between this angle and toe-gripping strength (r = 0.61). Thus, toe-gripping strength increased with the angle of dorsiflexion. Regarding the leg muscle activities, activities of the tibialis anterior muscle and medial head of the gastrocnemius muscle demonstrated positive correlations with toe-gripping strength (r = 0.75 and r = 0.72, respectively). [Conclusion] These findings suggest that the ankle dorsiflexes in order to exert great toe-gripping strength, and the crural muscles contract simultaneously because of ankle fixation.

Frequency domain approach for time-resolved pump-probe microscopy using intensity modulated laser diodes

We present a scheme for time-resolved pump-probe microscopy using intensity modulated laser diodes. The modulation frequencies of the pump and probe beams are varied up to 500 MHz with fixed frequency detuning typically set at 15 kHz. The frequency response of the pump-probe signal is detected using a lock-in amplifier referenced at the beat frequency. This frequency domain method is capable of characterizing the nanosecond to picosecond relaxation dynamics of sample species without the use of a high speed detector or a high frequency lock-in amplifier. Furthermore, as the pump-probe signal is based on the nonlinear interaction between the two laser beams and the sample, our scheme provides better spatial resolution than the conventional diffraction-limited optical microscopes. Time-resolved pump-probe imaging of fluorescence beads and aggregates of quantum dots demonstrates that this method is useful for the microscopic analysis of optoelectronic devices. The system is implemented using compact and low-cost laser diodes, and thus has a broad range of applications in the fields of photochemistry, optical physics, and biological imaging.

In-beam Mössbauer spectroscopy of (57)Fe/(57)Mn in MgO and NaF at Heavy-Ion Medical Accelerator in Chiba

Development of efficient ion supply of (58)Fe from (58)Fe(C5H5)2, and quick switching between therapy and material science at the Heavy-Ion Medical Accelerator in Chiba realized a new (57)Mn in-beam emission Mössbauer spectroscopy measurement system. Application to simple binary chemical compounds, MgO and NaF, proved the usefulness of the system to probe chemical and physical behaviors of trace impurities in solids. Annealing of lattice defects produced by the implantation and β-decay of (57)Mn and/or γ-ray emission recoil was observed by a local probe.

Contribution of fetal ANXA5 gene promoter polymorphisms to the onset of pre-eclampsia

OBJECTIVE

A common haplotype M2 consisting of minor SNP alleles located in the ANXA5 gene promoter region has been described as a risk factor for various obstetric complications such as recurrent pregnancy loss, pre-eclampsia and pregnancy-related thrombophilic disorder. However, the question of whether it is the maternal or fetal genotype that contributes to the onset of these disorders remains to be resolved.

METHODS

We analyzed ANXA5 gene variants in the blood and placental tissues from pre-eclampsia patients and normotensive controls. ANXA5 expression was examined by qRT-PCR, Western blotting and immunostaining. Results were compared between M2 and non-M2 carriers.

RESULTS

The M2 haplotype was found to be significantly frequent in placentas from pre-eclamptic patients relative to the controls (25.5% versus 10%, P = 0.044), In contrast, no significant differences were observed in maternal blood (13.0% versus 11.3%, P = 0.597). The placental expression of ANXA5 mRNA was found to be lower in M2 carriers. When examined by Western blot and immunostaining, the ANXA5 protein levels were found to be affected more by the placental than the maternal genotype. Histological examination of the placentas from the pre-eclamptic patients demonstrated that a placental M2 haplotype correlated more closely than maternal M2 with the severity of perivillous fibrin deposition.

CONCLUSIONS

Although preliminary, these results suggest that hypomorphic M2 alleles in the in placental ANXA5 promoter, whether transmitted maternally or paternally, might be an essential determinant of an increased risk of pre-eclampsia via local thrombophilia at the feto-maternal interface.

Electronic phase transition and an anomalous ordered phase in Ba2Ti13O22 with 3d1 ions on a triangle-based lattice

We found that Ba(2)Ti(13)O(22) with Ti(3+) (3d(1)) ions on a triangle-based lattice exhibits a phase transition at T(c)~200 K, below which the increase of electrical resistivity and decrease of magnetic susceptibility were observed. Transmission electron microscopy and optical reflectivity measurements indicate that the low-temperature phase of the present compound shares characteristics in common with a charge-density-wave state with remnant carriers, although a commensurate wave vector of the modulation and a linear temperature dependence of the magnetic susceptibility below T(c) suggest an exotic ordered state.

E-cadherin and c-met expression as a prognostic factor in gastric cancer

E-cadherin has an important role in the cell-cell adhesion and is known as an invasion suppressor gene. The c-met, which is a receptor of hepatocyte growth factor receptor, is involved in the proliferative and motile activity in cancer cells. The invasive and metastatic capacities of gastric cancer were studied from the immunohistochemically examined expression of MET and E-cadherin. Among 127 primary gastric cancers, 47 (34%) tumors were found to have preserved E-cadherin expression and the other 84 tumors showed reduced E-cadherin expression. MET expression was found in 55 (43%) tumors. A strong correlation was found between reduced E-cadherin expression and a larger tumor, positive serosal invasion, lymph node metastases or poor prognosis. Tumors with MET expression have the tendencies to invade deeply, to metastasize in more remote lymph nodes or peritoneum and to run a poor prognosis. MET over-expression and reduced E-cadherin expression were strongly associated with lymph node metastasis, peritoneal dissemination and poor prognosis. This group of patients with simultaneously abnormal expressions of these genes had a sixfold relative risk of death, as compared with patients with tumors showing MET negative or preserved E-cadherin expression. These results indicate that immunohistochemical combined analyses of MET and E-cadherin expression may be a powerful tool for the evaluation of invasive capacity and the prognosis of gastric cancer patients.

A SOS3 homologue maps to HvNax4, a barley locus controlling an environmentally sensitive Na+ exclusion trait

Genes that enable crops to limit Na(+) accumulation in shoot tissues represent potential sources of salinity tolerance for breeding. In barley, the HvNax4 locus lowered shoot Na(+) content by between 12% and 59% (g(-1) DW), or not at all, depending on the growth conditions in hydroponics and a range of soil types, indicating a strong influence of environment on expression. HvNax4 was fine-mapped on the long arm of barley chromosome 1H. Corresponding intervals of ∼200 kb, containing a total of 34 predicted genes, were defined in the sequenced rice and Brachypodium genomes. HvCBL4, a close barley homologue of the SOS3 salinity tolerance gene of Arabidopsis, co-segregated with HvNax4. No difference in HvCBL4 mRNA expression was detected between the mapping parents. However, genomic and cDNA sequences of the HvCBL4 alleles were obtained, revealing a single Ala111Thr amino acid substitution difference in the encoded proteins. The known crystal structure of SOS3 was used as a template to obtain molecular models of the barley proteins, resulting in structures very similar to that of SOS3. The position in SOS3 corresponding to the barley substitution does not participate directly in Ca(2+) binding, post-translational modifications or interaction with the SOS2 signalling partner. However, Thr111 but not Ala111 forms a predicted hydrogen bond with a neighbouring α-helix, which has potential implications for the overall structure and function of the barley protein. HvCBL4 therefore represents a candidate for HvNax4 that warrants further investigation.

Formation of a three-dimensional network of V trimers in A2V13O22 (A=Ba, Sr)

We found that in A2V13O22 (A=Ba, Sr), which contains a trilayer slab of VO in the sodium-chloride structure with periodically missing ions, the trimerization of V ions occurs at 290 K (A=Ba) and 380 K (A=Sr). V trimers form a three-dimensional network, but some V ions remain untrimerized in these compounds. The suppression of magnetic susceptibility with trimerization and the existence of a Curie tail at low temperatures, together with the result of NMR measurement, indicate that the V trimers are spin singlet, whereas the untrimerized V ions have a magnetic moment; i.e., there is a spontaneous separation between nonmagnetic and magnetic ions in the crystal.

Physical analysis of the complex rye (Secale cereale L.) Alt4 aluminium (aluminum) tolerance locus using a whole-genome BAC library of rye cv. Blanco

Rye is a diploid crop species with many outstanding qualities, and is important as a source of new traits for wheat and triticale improvement. Rye is highly tolerant of aluminum (Al) toxicity, and possesses a complex structure at the Alt4 Al tolerance locus not found at the corresponding locus in wheat. Here we describe a BAC library of rye cv. Blanco, representing a valuable resource for rye molecular genetic studies, and assess the library's suitability for investigating Al tolerance genes. The library provides 6 x genome coverage of the 8.1 Gb rye genome, has an average insert size of 131 kb, and contains only ~2% of empty or organelle-derived clones. Genetic analysis attributed the Al tolerance of Blanco to the Alt4 locus on the short arm of chromosome 7R, and revealed the presence of multiple allelic variants (haplotypes) of the Alt4 locus in the BAC library. BAC clones containing ALMT1 gene clusters from several Alt4 haplotypes were identified, and will provide useful starting points for exploring the basis for the structural variability and functional specialization of ALMT1 genes at this locus.

Pdx-1-independent differentiation of mouse embryonic stem cells into insulin-expressing cells

To investigate whether insulin-producing cells obtained from ES cells via the nestin-positive cell-mediated method are of the pancreatic lineage, we established a pdx-1 knockout ES cell line and analyzed its differentiation into insulin-producing cells. As a result, pdx-1 knockout ES cell expressed insulin 2 gene at the final differentiated cells. Thus, our study demonstrated that pdx-1 is not essential for insulin gene expression, at least in cells differentiated from this population of nestin-expression enriched ES cells, and suggested that the insulin-producing cells derived from ES cells may be different from the pancreatic beta cells in terms of their lineage.

Method for determining a coupling function in coupled oscillators with application to Belousov-Zhabotinsky oscillators

A coupling function that describes the interaction between self-sustained oscillators in a phase equation is derived and applied experimentally to Belousov-Zhabotinsky (BZ) oscillators. It is demonstrated that the synchronous behavior of coupled BZ reactors is explained extremely well in terms of the coupling function thus obtained. This method does not require comprehensive knowledge of either the oscillation mechanism or the interaction among the oscillators, both of these being often difficult to elucidate in an actual system. These facts enable us to accurately analyze the weakly coupled entrainment phenomenon through the direct measurement of the coupling function.