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Background: Standard surgery for upper advanced gastric cancer without invasion of the greater curvature (UGC‐GC) is spleen‐preserving D2 total gastrectomy without dissection of the splenic‐hilar nodes (#10). However, some patients with nodal metastasis to #10 survive more than 5 years due to nodal dissection of #10. If nodal metastasis to #10 is predictable based on the positivity of other nodes dissected by the current standard surgery without #10 nodal dissection, physicians may be able to consider #10 dissection. Methods: This study retrospectively reviewed data from the National Cancer Center Hospital in Japan between 2000 and 2012. We selected cases that met the following criteria: (1) D2 or more total gastrectomy with splenectomy, (2) UGC‐GC, and (3) histological type is gastric adenocarcinoma. We performed univariate and multivariate analyses concerning lymph node stations associated with #10 metastasis. Results: A total of 366 patients were examined. A multivariate analysis revealed that #10 metastasis was associated with positivity of the nodes along the short gastric arteries (#4sa) and distal nodes along the splenic artery (#11d) (#4sa: p = 0.003, #11d: p = 0.016). When either key node was positive, the metastatic rate of #10 was 24.4%, and the therapeutic value index was 13.3. Conclusions: #4sa and #11d were key lymph nodes predicting #10 nodal metastasis in UGC‐GC. When these key nodes are positive on computed tomography before surgery or according to a rapid pathological examination during surgery, dissection of #10 should be considered even if upper advanced tumors are not invading the greater curvature. [ABSTRACT FROM AUTHOR]

Background: This study was performed to evaluate the orientation of lower esophageal sphincter (LES) pressure in patients with untreated achalasia using three-dimensional high-resolution manometry (3DHRM). Methods: The study involved 20 patients with untreated achalasia (10 men, 60 [47-74] years of age). The 3D-HRM assembly had 32 standard channels and 12 3D channels. During basal LES pressure measurements, the orientations of the LES high- and low-pressure zones were evaluated at end-expiration. The directional relationships between the orientation of the LES high- and low-pressure zones were also evaluated. Results: The LES high-pressure zones were located on the greater curvature side in nine (45%) patients, from the greater curvature to posterior wall side in six (30%), and from the greater curvature to anterior wall side in five (25%). The LES high-pressure zones were located mainly on the greater curvature side, but there were some variations of the orientation among the patients. The LES low-pressure zones were most frequently located from the lesser curvature to the posterior wall side in 11 (55%) patients, from the lesser curvature to anterior wall side in 6 (30%), on the posterior wall side in 2 (10%), and on the anterior wall side in 1 (5%). Significant differences were found in the directional relationships between the orientation of the LES high- and low-pressure zones (P = 0.0053). Conclusions: This is the first report from Japan focusing on the LES pressure orientation using 3DHRM. Such evaluation may be useful for clarifying the pathophysiology of achal [ABSTRACT FROM AUTHOR]

Guided bone regeneration is the most commonly used technique for vertical ridge augmentation (VRA), and it is popular because it is less invasive and highly formative. Since the augmented site is exposed to external pressure, it is preferable to support the membrane using a framework to maintain the shape of the VRA. Recently, a titanium framework–reinforced ultrafine titanium membrane was developed by laser processing technology. The technique allows microperforations to be made (φ20 μm) into a titanium membrane, which is expected to prevent fibrous tissue ingrowth from outside the membrane. In addition, significant bone regeneration was confirmed on ridge defects in previous animal studies. However, the membrane tends to crumple during the bending process, because it is very thin (20 nμm); thus, the bending procedures are technically sensitive. Since this titanium honeycomb membrane was first approved for clinical use in Japan, no international clinical reports have been published. The purpose of this case report is to describe a technical note for a 3-dimensional curvature bending method in VRA using the newly developed honeycomb structure titanium membrane. [ABSTRACT FROM AUTHOR]

Splenectomy for advanced gastric stump cancer (GSC) is performed in Japan, based on the concept that lymphatic flow toward the splenic hilum is dominant following initial gastrectomy. However, little has been reported on the therapeutic impact of complete splenic hilar dissection with splenectomy. A total of 184 patients who underwent R0 total gastrectomy with or without splenectomy for GSC between 1998 and 2015 were included in this retrospective analysis. Patients were divided into subgroups: patients with tumors involving the greater curvature (Gre group) and tumors without greater curvature involvement (non-Gre group), and each group was further divided into those with and without splenectomy. The incidence of lymph node (LN) metastasis, index of the estimated benefit from LN dissection in each station, and survival curves were compared. The incidence of No.10 LN metastasis was higher in the Gre group than in the non-Gre group (16.7% vs. 2.0%, P = 0.036). The index of No.10 LN dissection was higher in the Gre group than in the non-Gre group (6.3 vs. 0). However, there was no tendency that splenectomy was superior to spleen preservation for survival outcomes in either group, although selection bias certainly existed. In advanced GSC, similar to primary advanced proximal gastric cancer, splenectomy can be omitted unless the tumor infiltrates the greater curvature. Complete splenic hilar dissection may be expected to be beneficial for some patients with tumors infiltrating the greater curvature. [ABSTRACT FROM AUTHOR]

For airborne gravity gradiometry in rugged terrain, helicopters offer a significant advantage over fixed‐wing aircraft: their ability to maintain much lower ground clearances. Crucially, this provides both better signal‐to‐noise and better spatial resolution than is possible with a fixed‐wing survey in the same terrain. Comparing surveys over gentle terrain at Margaret Lake, Canada, and over rugged terrain at Mount Aso, Japan, demonstrates that there is some loss of spatial resolution in the more rugged terrain. The slightly higher altitudes forced by rugged terrain make the requirements for terrain correction easier than for gentle terrain. Transforming the curvature gradients measured by the Falcon gravity gradiometer into gravity and the complete set of tensor components is done by a Fourier method over gentle terrain and an equivalent source method for rugged terrain. The Fourier method is perfectly stable and uses iterative padding to improve the accuracy of the longer wavelengths. The equivalent source method relies on a smooth model inversion, and the source distribution must be designed to suit the survey design. [ABSTRACT FROM AUTHOR]

Purpose: To determine the early signs of posterior staphylomas in highly myopic eyes of younger subjects by swept-source ultra-widefield optical coherence tomography (WF-OCT). Methods: This was an observational case series study. Highly myopic subjects younger than 20 years old who were examined consecutively by prototype WF-OCT were studied. High myopia was defined according to the Ministry of Health and Welfare, Japan classification. A posterior displacement of the sclera and two OCT features indicating the staphyloma edges were used as markers of a staphyloma. Results: Fifty-five eyes of 30 patients with the mean age of 12.3 years, and the mean axial length of 27.9 mm were studied. Seven of the 55 eyes (12.7%) had a posterior displacement of the sclera and were diagnosed as having a staphyloma. Among the two OCT features of the staphyloma edges, a gradual thinning of the choroid toward the staphyloma edge and gradual re-thickening of choroid from the staphyloma edge toward the posterior pole were found in these 7 eyes. However, the other feature of an inward protrusion of the sclera at the staphyloma edge, was obvious in only 2 eyes. The subfoveal choroid and choroid nasal to the optic disc were significantly thinner in eyes with a staphyloma than those without it. Conclusions: The changes of the choroidal thickness toward the staphyloma edge with the posterior displacement of the sclera were considered an early sign which precedes an inward protrusion of sclera at the staphyloma edge. [ABSTRACT FROM AUTHOR]

This study investigated differences in the fibular diaphyseal curvature between prehistoric Jomon hunter-gatherers and modern Japanese people. A total of 115 skeletal remains of 40 individuals from the Late/Final Jomon period (approximately 4300-2500 years BP) and 75 modern Japanese individuals were included in the analysis. The degree of anteroposterior and mediolateral diaphyseal curvature was measured based on digital photographs taken from the frontal and sagittal planes at every 5% diaphyseal region between the range of 20-80% of the fibular length. Fibular diaphyseal curvature was compared between both populations and sexes, and the correlation between fibular diaphyseal curvature with diaphyseal cross-sectional morphology and body size variables were confirmed. The results showed significant differences in the anteroposterior diaphyseal curvature between the Jomon and modern Japanese populations, and a significantly curved anterior direction was noted for Jomon males and females, compared with modern Japanese males and females. On the contrary, little populational difference was noted in terms of mediolateral diaphyseal curvature. The curvature of the fibular diaphysis showed less correlation with body size variables. Moreover, anteroposterior diaphyseal curvatures were correlated with diaphyseal robustness and had low correlation with diaphyseal shape. A relationship between anteroposterior curvature and diaphyseal cross-sectional morphology, an indicator of habitual activity, was confirmed. This suggests that the fibular curvature is possibly influenced by mechanical loading from daily activities as well., (© 2023. The Author(s), under exclusive licence to Japanese Association of Anatomists.)

The monetary policy targets the short rates; however, during zero interest rate policy (ZIRP), the short end of the yield curve cannot serve as a policy instrument. Relying on the joint yields-macro latent factors model, this study empirically examines the effect of monetary policy stances on term structure and the possible feedback effect on the real sector using the Japanese experience of ZIRP. The analysis indicates that it is the entire term structure that transmits the policy shocks to the real economy rather than the yield spread only. The monetary policy signals pass through the yield curve level and slope factors to stimulate the economic activity. The curvature factor, besides reflecting the cyclical fluctuations of the economy, acts as a leading indicator for future inflation. In addition, policy influence tends to be low as the short end becomes segmented toward medium/long-term of the yield curve. Furthermore, volatility in bond markets is found to be asymmetrically affected by positive and negative shocks and long end tends to be less sensitive to stochastic shocks than the short maturities. The expectation hypothesis of the term structure does not hold during the ZIRP period. [ABSTRACT FROM PUBLISHER]

Background: Recently, laparoscopic-assisted distal gastrectomy (LADG) has become popular for the treatment of early gastric cancer. Furthermore, the use of totally laparoscopic gastrectomy (TLG), a more difficult procedure than LADG, has been increasing in Japan. Laparoscopic-assisted distal gastrectomy is currently performed more frequently than laparoscopic distal gastrectomy (LDG) in hospitals in Japan. Method: Reconstruction after LDG is commonly performed extra-abdominally and lymph node dissection of the lesser curvature is performed at the same time. We have developed a new method of intra-abdominal lymph node dissection for the lesser curvature. Results: Our technique showed positive results, is easy to perform, and is reasonable in terms of general oncology theory. Conclusion: In oncological therapy, this technique could be a valuable surgical option for totally laparoscopic surgery. [ABSTRACT FROM AUTHOR]

This paper summarizes an experimental and analytical study on the seismic behavior of high strength reinforced concrete columns under cyclic loading. In total six cantilever columns with different sizes and concrete compressive strengths were tested. Three columns, small size, had a 325 x 325 mm cross section and the three other columns, medium size, were 520 x 520 mm. Concrete compressive strength was 80, 130 and 180 MPa. All specimens were designed in accordance with the Japanese design guidelines. The tests demonstrated that, for specimens made of 180 MPa concrete compressive strength, spalling of cover concrete was very brittle followed by a significant decrease in strength. Curvature was much important for the small size than for the medium size columns. Concrete compressive strength had no effect on the curvature distribution for a drift varying between -2% and +2%. However, it had an effect on the drift corresponding to the peak moment and on the equivalent viscous damping variation. Simple equations are proposed for 1) evaluating the concrete Young's modulus for high strength concrete and for 2) evaluating the moment-drift envelope curves for the medium size columns knowing that of the small size columns. Experimental moment-drift and axial strain-drift histories were well predicted using a fiber model developed by the authors. [ABSTRACT FROM AUTHOR]

Dispersive fibers are fabricated in which the refractive index dispersions of the core and cladding cross at a certain wavelength. The core and cladding were made of different types of optical glasses. To pass a long wavelength light (to suppress short wavelength light), the refractive index of the core was chosen to be lower than that of the cladding in the short wavelength region. In the fabricated dispersive fibers, no waveguide mode was observed in the short wavelength region, indicating that the fibers play the role of a long wavelength pass filter. To evaluate the fibers as an optical filter, the transmission loss and insertion loss were investigated and it was found that the pass wavelength region could be controlled by changing the curvature of the fibers. [ABSTRACT FROM AUTHOR]

Age- or sex-related differences in femoral curvature affect the onset of trauma or degenerative diseases of the hip joints. This study aimed to investigate femoral curvature in detail in Japanese individuals using three-dimensional computed tomography, evaluate its effects on the position of proximal femur, and assess differences in femoral curvature according to age and sex. We measured sagittal and coronal femoral bowing in 40 elderly (mean age 85.2 years) and 40 adult (mean age 30.1 years) Japanese individuals using computed tomography. In adult individuals, the radii of the femoral curvatures of the distal end and shaft in the coronal planes were significantly smaller in women than in men. In contrast, no significant difference was observed in femoral curvature between the sexes in the elderly group. Furthermore, the radius of femoral curvature was significantly smaller in elderly individuals than in adult individuals, regardless of the sex and location of the measurement. The highest point of the greater trochanter of the femoral head center was 7.3 ± 5.6 mm in the elderly group and 2.2 ± 4.6 mm in the adult group (p < 0.05). Thus, the femoral curvature varies with age and sex in Japanese individuals. In addition, the femoral curvature could cause positional changes in the proximal femur, such as the highest point of the greater trochanter. Therefore, further studies investigating the biomechanical effects of these morphological changes are warranted.

Background: Detecting the onset of influenza epidemic is important for epidemiological surveillance and for investigating the factors driving spatiotemporal transmission patterns. Most approaches define the epidemic onset based on thresholds, which use subjective criteria and are specific to individual surveillance systems.Methods: We applied the empirical threshold method (ETM), together with two non-thresholding methods, including the maximum curvature method (MCM) that we proposed and the segmented regression method (SRM), to determine onsets of influenza epidemics in each prefecture of Japan, using sentinel surveillance data of influenza-like illness (ILI) from 2012/2013 through 2017/2018. Performance of the MCM and SRM was evaluated, in terms of epidemic onset, end, and duration, with those derived from the ETM using the nationwide epidemic onset indicator of 1.0 ILI case per sentinel per week.Results: The MCM and SRM yielded complete estimates for each of Japan's 47 prefectures. In contrast, ETM estimates for Kagoshima during 2012/2013 and for Okinawa during all six influenza seasons, except 2013/2014, were invalid. The MCM showed better agreement in all estimates with the ETM than the SRM (R2 = 0.82, p < 0.001 vs. R2 = 0.34, p < 0.001 for epidemic onset; R2 = 0.18, p < 0.001 vs. R2 = 0.05, p < 0.001 for epidemic end; R2 = 0.28, p < 0.001 vs. R2 < 0.01, p = 0.35 for epidemic duration). Prefecture-specific thresholds for epidemic onset and end were established using the MCM.Conclusions: The Japanese national epidemic onset threshold is not applicable to all prefectures, particularly Okinawa. The MCM could be used to establish prefecture-specific epidemic thresholds that faithfully characterize influenza activity, serving as useful complements to the influenza surveillance system in Japan. [ABSTRACT FROM AUTHOR]

Background: While various implants are currently used for the treatment of femoral trochanteric fractures in Japan, 'mismatches' have been known to occur between patient and implant type. The purpose of this study is to identify morphological characteristics of elderly Japanese females, both in terms of the shape of proximal femur and its anterior curvature in order to evaluate the suitability of implants for treatment of femoral trochanteric fractures using 3D-computed tomography (CT) scanning., Methods: This study used CT scan data taken from 50 elderly females (aged 70 years or older). Neck-shaft (NS) angle and height of the greater trochanter (GT) were measured under defined conditions (TPI: theoretical plane to place implant). Anterior curvature of the femoral shaft was also measured., Results: On average, the NS angle was found to be 128.1° and GT height was 62.4 mm. Average curvature radius was 1040 mm. As for the NS angle, the centrum-collum-diaphysis angles of existing implants (125° or 130°) are reasonable. In elderly Japanese patients, the proximal femur shows specific characteristics. As GT height is very short, the implant may easily interfere with the lateral cortex. Additionally, the curvature radius calculated (1040 mm) was smaller than that of past reports, indicating strong curvature in the Japanese elderly., Conclusion: Our measurement results are potentially useful in the avoidance of intraoperative trouble caused by mismatch of implants.