Anomalous behavior of the spin gap of a spin-1/2 two-leg antiferromagnetic ladder with Ising-like rung interactions

Using mainly numerical methods, we investigate the width of the spin gap of a spin-1/2 two-leg ladder described by \cH= J_\rl \sum_{j=1}^{N/2} [ \vS_{j,a} \cdot \vS_{j+1,a} + \vS_{j,b} \cdot \vS_{j+1,b} ] + J_\rr \sum_{j=1}^{N/2} [\lambda (S^x_{j,a} S^x_{j,b} + S^y_{j,a} S^y_{j,b}) + S^z_{j,a} S^z_{j,b}] , where $S^\alpha_{j,a(b)}$ denotes the $\alpha$-component of the spin-1/2 operator at the $j$-th site of the $a (b)$ chain. We mainly focus on the J_\rr \gg J_\rl > 0 and $|\lambda| \ll 1$ case. The width of the spin gap as a function of $\lambda$ anomalously increases near $\lambda = 0$; for instance, for $-0.1 < \lambda < 0.1$ when $J_{\rm l}/J_{\rm r} = 0.1$. The gap formation mechanism is thought to be different for the $\lambda 0$ cases. Since, in usual cases, the width of the gap becomes zero or small at the point where the gap formation mechanism changes, the above gap-increasing phenomenon in the present case is anomalous. We explain the origin of this anomalous phenomenon by use of the degenerate perturbation theory. We also draw the ground-state phase diagram.Comment: 4 pages, 11 figures; Proc. "The International Conference on Quantum Criticality and Novel Phases" (2012), to be published in Phys. Stat. Solidi

Interleukin-6 as a Potential Therapeutic Target for Pulmonary Arterial Hypertension

Interleukin-6 (IL-6) is a pleiotropic cytokine with a wide range of biologic activities in immune regulation, hematopoiesis, inflammation, and oncogenesis. Recent accumulating evidence indicates a pathologic role for IL-6 in promoting proliferation of both smooth muscle and endothelial cells in the pulmonary arterioles, resulting in development of pulmonary arterial hypertension (PAH). Here, we describe a patient with mixed connective tissue disease and severe, refractory PAH. Her functional activity and hemodynamic parameters dramatically responded to tocilizumab, a humanized monoclonal antibody to human IL-6 receptor, which was aimed at treating multicentric Castleman's disease. It appears that IL-6 blockade may hold promise as an adjunct drug in treatment of PAH in idiopathic form as well as in association with connective tissue disease

IL-23 induces human osteoclastogenesis via IL-17 in vitro, and anti-IL-23 antibody attenuates collagen-induced arthritis in rats

This study demonstrates that IL-23 stimulates the differentiation of human osteoclasts from peripheral blood mononuclear cells (PBMC). Furthermore, in vivo blockade of endogenous IL-23 activity by treatment with anti-IL-23 antibody attenuates collagen-induced arthritis in rats by preventing both inflammation and bone destruction. IL-23 induced human osteoclastogenesis in cultures of PBMC in the absence of osteoblasts or exogenous soluble-receptor activator of NF-kappaB ligand (RANKL). This IL-23-induced osteoclastogenesis was inhibited by osteoprotegerin, anti-IL-17 antibody, and etanercept, suggesting that RANKL, IL-17, and TNF-alpha are involved. In addition, we found the ratio of production levels of IL-17 to those of IFN-gamma from activated human T cells was elevated at 1 to 10 ng/ml IL-23. The inductive effect of IL-17 and the inhibitory effect of IFN-gamma on osteoclastogenesis indicate that the balance of these two cytokines is particularly important. We also demonstrated that IL-23 administered at a later stage significantly reduced paw volume in rats with collagen-induced arthritis, in a dose-dependent manner. Furthermore, anti-IL-23 antibody reduced synovial tissue inflammation and bone destruction in these rats. These findings suggest that IL-23 is important in human osteoclastogenesis and that neutralizing IL-23 after onset of collagen-induced arthritis has therapeutic potential. Thus, controlling IL-23 production and function could be a strategy for preventing inflammation and bone destruction in patients with rheumatoid arthritis

Basic assessment on adding platelet measurement to legal health checkup in Japan: A cross-sectional and 20-year longitudinal study

BackgroundIn Japan, health checkups for workers are legally compulsory. Considering legal health checkup items are important for Japanese workers' health problems. To date, the legal health checkup items for blood cell counts include only red blood cell counts and hemoglobin but not platelet counts. This study aimed to investigate the significance of measuring platelets in workers by showing the association between the FIB-4 index (FIB-4), which can be easily calculated from factors including platelet counts and viral hepatitis infection.MethodBoth cross-sectional and longitudinal analyses were conducted on the comprehensive medical examinations of male workers. In fiscal year (FY) 2019, a logistic regression model was applied to 12,918 examinees. For 13,459 examinees (mean age = 47.5 ± 9.3 SD), FY2000 was set to be followed until FY2019. A total of 149,956 records between FY2000 and FY2019 were analyzed cross-sectionally, and 8,038 men who were consecutively examined to FY2019 at the longest were analyzed longitudinally. Receiver operating characteristic (ROC) curve–area under the ROC curve (ROC–AUC) and Cox proportional methods were used to examine the association between platelet-related indices and viral hepatitis infection.ResultsLogistic regression showed that the risk of FIB-4 ≥ 2.67 was mostly associated with hepatitis C virus antibody (HCVAb) positivity [odds ratio (OR) = 2.51, 95% confidence interval (CI) = 1.08–5.86], while negatively associated with body mass index (BMI) (OR = 0.54, 95% CI = 0.30–0.97), and not associated with the presence of fatty liver. To detect HVC Ab positivity, ROC–AUC showed more effectiveness in FIB-4 than in the AST/ALT ratio (0.776, 95% CI = 0.747–0.773 vs. 0.552; 95% CI = 0.543–0.561). The Cox analysis showed that the risk of FIB-4 ≥ 2.67 was closely associated with hepatitis B virus surface antigen (HBsAg) [hazard ratio (HR) = 3.1, 95% CI = 2.0–4.6] and HCV Ab positivity (HR = 3.2, 95% CI = 2.0–5.0).ConclusionOur results suggest that it might be worth considering that usage of information on platelets in legal health checkups could be some help not to overlook workers with hepatitis virus carriers as a complementary countermeasure, although further investigations are needed into its practical application

Regioselective glucosidation of trans-resveratrol in Escherichia coli expressing glucosyltransferase from Phytolacca americana

A glucosyltransferase (GT) of Phytolacca americana (PaGT3) was expressed in Escherichia coli and purified for the synthesis of two O-β-glucoside products of trans-resveratrol. The reaction was moderately regioselective with a ratio of 4′-O-β-glucoside: 3-O-β-glucoside at 10:3. We used not only the purified enzyme but also the E. coli cells containing the PaGT3 gene for the synthesis of glycoconjugates. E. coli cell cultures also have other advantages, such as a shorter incubation time compared with cultured plant cells, no need for the addition of exogenous glucosyl donor compounds such as UDP-glucose, and almost complete conversion of the aglycone to the glucoside products. Furthermore, a homology model of PaGT3 and mutagenesis studies suggested that His-20 would be a catalytically important residue

Elevated Levels of Serum Pentosidine Are Associated with Dropped Head Syndrome in Older Women

Study Design A retrospective observational study was performed. Purpose We investigated the prevalence of sarcopenia in dropped head syndrome (DHS), and the relationship between biochemical markers, including major advanced glycation end products (AGEs), pentosidine, and DHS in older women. Overview of Literature AGEs have been implicated in the pathogenesis of sarcopenia. Methods We studied 13 elderly women with idiopathic DHS (mean age, 77.2 years) and 20 healthy volunteers (mean age, 74.8 years). We used a bioelectrical impedance analyzer to analyze body composition, including appendicular skeletal muscle mass index (SMI; appendicular lean mass [kg]/[height (m)]2). Cervical sagittal plane alignment, including C2–C7 sagittal vertical axis (C2–C7SVA), C2–C7 angle, and C2 slope (C2S), was measured. Biochemical markers, such as serum and urinary pentosidine, serum homocysteine, 1, 25-dihydroxyvitamin D, and 25-hydroxyvitamin D, were measured. The level of each variable was compared between DHS and controls. The relationship between biochemical markers and DHS was examined. Results Sarcopenia (SMI <5.75) was observed at a high prevalence in participants with DHS (77% compared to 22% of healthy controls). Height, weight, femoral bone mineral density, appendicular lean mass, total lean mass, and SMI all had significantly lower values in the DHS group. Serum and urinary pentosidine, and serum homocysteine were significantly higher in the DHS group compared to controls. Analysis of cervical alignment revealed a significant positive correlation of serum pentosidine with C2–C7SVA and C2S. Conclusions Sarcopenia was involved in DHS, and high serum pentosidine levels are associated with severity of DHS in older women

Functional tooth number and mortality

Aim: Previous studies on the association between intraoral conditions and mortality in community-dwelling older individuals reported that fewer present teeth (PT) are significant risk factors for mortality. However, how the number of PT relative to the number of functional teeth (FT), including both present and rehabilitated teeth, influences mortality has not been investigated fully. This study examined the impact of the number of FT on mortality among community-dwelling Japanese older adults. Methods: This study was a retrospective, observational and population-based follow-up study, which examined 1188 older individuals who participated in an annual geriatric health examination from 2009 to 2015. The average follow-up period was 1697.0 ± 774.5 days. The primary outcome was all-cause mortality at follow-up. The numbers of PT and FT of each participant were counted during an oral examination. In addition, demographics, clinical variables, blood nutrient markers, physical functions and perceived masticatory function were measured. Results: Kaplan–Meier analysis, followed by a log-rank test, revealed that fewer PT (P < 0.001) and FT (P = 0.002) were significantly associated with a reduced survival rate. Cox's proportional hazard analysis indicated that the number of FT, but not the number of PT, was a significant independent mortality risk factor after adjusting for demographics, clinical variables, nutrient markers and physical functioning (P = 0.036, hazard ratio: 2.089). Conclusions: Current results suggest that the number of FT more strongly predicts all-cause mortality than the number of PT among community-dwelling older adults. Further studies are necessary to consider the confounding of socioeconomic status and disability status

Number of functional teeth more strongly predicts all‐cause mortality than number of present teeth in Japanese older adults

Aim Previous studies on the association between intraoral conditions and mortality in community‐dwelling older individuals reported that fewer present teeth (PT) are significant risk factors for mortality. However, how the number of PT relative to the number of functional teeth (FT), including both present and rehabilitated teeth, influences mortality has not been investigated fully. This study examined the impact of the number of FT on mortality among community‐dwelling Japanese older adults. Methods This study was a retrospective, observational and population‐based follow‐up study, which examined 1188 older individuals who participated in an annual geriatric health examination from 2009 to 2015. The average follow‐up period was 1697.0 ± 774.5 days. The primary outcome was all‐cause mortality at follow‐up. The numbers of PT and FT of each participant were counted during an oral examination. In addition, demographics, clinical variables, blood nutrient markers, physical functions and perceived masticatory function were measured. Results Kaplan–Meier analysis, followed by a log‐rank test, revealed that fewer PT (P  Conclusions Current results suggest that the number of FT more strongly predicts all‐cause mortality than the number of PT among community‐dwelling older adults. Further studies are necessary to consider the confounding of socioeconomic status and disability status

Impact of number of functional teeth on independence of Japanese older adults

Aim To examine the relationship between the number of present and functional teeth at baseline and future incidence of loss of independence. Methods Participants were community-dwelling older individuals who participated in a comprehensive geriatric health examination conducted in Kusatsu town, Japan, between 2009 and 2015. The primary endpoint was the incidence of loss of independence among participants, defined as the first certification of long-term care insurance in Japan. The numbers of present and functional teeth at baseline were determined via an oral examination. Demographics, clinical variables (e.g., history of chronic diseases and psychosocial factors), blood nutritional markers, physical functions, and perceived masticatory function were assessed. Results This study included 1121 individuals, and 205 individuals suffered from loss of independence during the follow-up period. Kaplan–Meier estimates of loss of independence for participants with smaller numbers of present and functional teeth were significantly greater than for those with larger numbers of teeth. Cox proportional hazard analyses indicated that a smaller number of present teeth was not a significant risk factor after adjusting for demographic characteristics. However, the number of functional teeth was a significant risk factor after the adjustment (hazard ratio: 1.975 [1.168–3.340]). Additionally, higher hazard ratios were observed in other adjusted models, but they were not statistically significant. Conclusions The number of functional teeth may be more closely related to the future incidence of loss of independence than the number of present teeth. This novel finding suggests that prosthodontic rehabilitation for tooth loss possibly prevents the future incidence of this life-event