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In Arabidopsis thaliana, the ACL5 gene encodes thermospermine synthase and its mutant, acl5, exhibits a dwarf phenotype with excessive xylem formation. Studies of suppressor mutants of acl5 reveal the involvement of thermospermine in enhancing mRNA translation of the SAC51 gene family. We show here that a mutant, sac59, which partially suppresses the acl5 phenotype, has a point mutation in JMJ22 encoding a D6-class Jumonji C protein (JMJD6). A T-DNA insertion allele, jmj22-2, also partially suppressed the acl5 phenotype while mutants of its closest two homologs JMJ21 and JMJ20 had no such effects, suggesting a unique role for JMJ22 in plant development. We found that mRNAs of the SAC51 family are more stabilized in acl5 jmj22-2 than in acl5., (© 2022 Federation of European Biochemical Societies.)

The endoplasmic reticulum (ER) is responsible for folding secretory and membrane proteins, but disturbed ER proteostasis may lead to protein aggregation and subsequent cellular and clinical pathologies. Chemical chaperones have recently emerged as a potential therapeutic approach for ER stress-related diseases. Here, we identified 2-phenylimidazo[2,1- b ]benzothiazole derivatives (IBTs) as chemical chaperones in a cell-based high-throughput screen. Biochemical and chemical biology approaches revealed that IBT21 directly binds to unfolded or misfolded proteins and inhibits protein aggregation. Finally, IBT21 prevented cell death caused by chemically induced ER stress and by a proteotoxin, an aggression-prone prion protein. Taken together, our data show the promise of IBTs as potent chemical chaperones that can ameliorate diseases resulting from protein aggregation under ER stress., Competing Interests: KK, ST, EK, YH, MM, MO, HK, HK, TK, SY, TH, SO No competing interests declared, (© 2019, Kitakaze et al.)

The transplantation of dedifferentiated fat (DFAT) cells in combination with poly(d,l-lactic-co-glycolic acid) (PLGA) scaffolds has previously been proven as an effective approach in promoting periodontal tissue regeneration in a rat fenestration defect model. The aim of this study was to assess the regenerative potential of DFAT cells in a rat model of three-wall periodontal bone defect. Three-wall bone defects were created bilaterally on the mesial side of rat maxillary first molars and were either left untreated or treated by implantation of PLGA scaffolds with DFAT cells or PLGA alone. Four weeks after surgery, the tissues were processed for micro-computed tomography (micro-CT) and histomorphometric examination. Micro-CT revealed that the PLGA/DFAT group had significantly higher rates of bone regeneration than the other groups, while histomorphometric analysis showed that the PLGA/DFAT group had significantly higher densities of collagen fiber bundles in acellular and cellular cementum than the PLGA group. Moreover, the results indicate that the placement of the PLGA scaffold prevented the downgrowth of the junctional epithelium. These findings suggest that DFAT cells contribute to tissue regeneration in three-wall periodontal defects, while PLGA provides space necessary for periodontal tissue restoration.

We previously generated induced pluripotent stem (iPS) cells from human dental pulp cells of deciduous teeth. Neural crest cells (NCCs) play a vital role in the development of the oral and maxillofacial region. Therefore, NCCs represent a cell source for bone, cartilage, and tooth-related tissue engineering. In this study, we examined whether iPS cells are capable of differentiating into NCCs through modification of the human embryonic stem cell protocol. First, iPS cells were dissociated into single cells and then reaggregated in low-cell-adhesion plates with neural induction medium for 8 days in suspension culture to form neurospheres. The neurospheres were transferred to fibronectin-coated dishes and formed rosette structures. The migrated cells from the rosettes abundantly expressed NCC markers, as evidenced by real-time polymerase chain reaction, immunofluorescence, and flow cytometric analysis. Furthermore, the migrated cells exhibited the ability to differentiate into neural crest lineage cells in vitro. They also exhibited tissue-forming potential in vivo, differentiating into bone and cartilage. Collectively, the migrated cells had similar characteristics to those of NCCs. These results suggest that human dental pulp cell-derived iPS cells are capable of differentiating into NCCs. Therefore, iPS cell-derived NCCs represent cell sources for bone and cartilage tissue engineering.

Bone marrow-derived multipotent stromal cells (BMSCs) have potent antiinflammatory effects. This study aimed to investigate the antiinflammatory potential of BMSCs using a mouse model of ligature-induced periodontitis. BMSCs were isolated from the femurs and tibiae of mice. Periodontitis was induced by placing a ligature around the right maxillary second molar. After 3 days, the mice were administered BMSC in the gingiva of the mesial interdental papilla around the ligatured molar. The ligatured and non-ligatured mice that were not administered BMSC served as controls. Differences in inflammatory infiltration and bone resorption around the roots of the second molar were assessed and were subsequently quantified using microcomputed tomography (micro-CT), histological analysis, and tartrate-resistant acid phosphatase (TRAP) staining. Micro-CT revealed that alveolar bone loss around the ligatured molars increased in a time-dependent manner; however, the effect was significantly less in BMSC-treated mice compared with ligatured control mice. Tissue histopathology revealed that BMSC administration mitigated inflammatory infiltration in ligatured BMSC mice. In addition, the number of TRAP-positive osteoclasts was markedly elevated in ligatured control mice compared with those in BMSC-treated mice. These findings indicate that local BMSC administration can mitigate inflammation and alveolar bone resorption, suggesting that administering BMSC leads to new therapeutics for periodontitis.

Thermospermine acts in negative regulation of xylem differentiation and its deficient mutant of Arabidopsis thaliana, acaulis5 (acl5), shows excessive xylem formation and severe dwarfism. Studies of two dominant suppressors of acl5, sac51-d and sac52-d, have revealed that SAC51 and SAC52 encode a transcription factor and a ribosomal protein L10 (RPL10), respectively, and these mutations enhance translation of the SAC51 mRNA, which contains conserved upstream open reading frames in the 5' leader. Here we report identification of SAC53 and SAC56 responsible for additional suppressors of acl5. sac53-d is a semi-dominant allele of the gene encoding a receptor for activated C kinase 1 (RACK1) homolog, a component of the 40S ribosomal subunit. sac56-d represents a semi-dominant allele of the gene for RPL4. We show that the GUS reporter activity driven by the CaMV 35S promoter plus the SAC51 5' leader is reduced in acl5 and restored by sac52-d, sac53-d, and sac56-d as well as thermospermine. Furthermore, the SAC51 mRNA, which may be a target of nonsense-mediated mRNA decay, was found to be stabilized in these ribosomal mutants and by thermospermine. These ribosomal proteins are suggested to act in the control of uORF-mediated translation repression of SAC51, which is derepressed by thermospermine.

In Japan at present, fecal occult blood testing (FOBT) is recommended for cancer screening while routine population-based prostate-specific antigen (PSA) screening is not. In future it may be necessary to increase participation in the former and decrease it in the latter. Our objectives were to explore determinants of PSA-screening participation while simultaneously taking into account factors associated with FOBT. Data were gathered from a cross-sectional study conducted with random sampling of 6191 adults in Osaka city in 2011. Of 3244 subjects (return rate 52.4%), 936 men aged 40-64 years were analyzed using log-binomial regression to explore factors related to PSA-screening participation within 1 year. Only responders for cancer screening, defined as men who participated in either FOBT or PSA-testing, were used as main study subjects. Men who were older (prevalence ratio [PR] [95% confidence interval (CI)] = 2.17 [1.43, 3.28] for 60-64 years compared with 40-49 years), had technical or junior college education (PR [95% CI] = 1.76 [1.19, 2.59] compared with men with high school or less) and followed doctors' recommendations (PR [95% CI] = 1.50 [1.00, 2.26]) were significantly more likely to have PSA-screening after multiple variable adjustment among cancer-screening responders. Attenuation in PR of hypothesized common factors was observed among cancer-screening responders compared with the usual approach (among total subjects). Using the analytical framework to account for healthy-user bias, we found three factors related to participation in PSA-screening with attenuated association of common factors. This approach may provide a more sophisticated interpretation of participation in various screenings with different levels of recommendation., (© 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.)

Background: Several studies have reported that individualized residential place-based discrimination (PBD) affects residents' health. However, studies exploring the association between institutionalized PBD and health are scarce, especially in Asian countries including Japan., Methods: A cross-sectional study was conducted with random two-stage sampling of 6191 adults aged 25-64 years in 100 census tracts across Osaka city in 2011. Of 3244 respondents (response rate 52.4%), 2963 were analyzed using multilevel logistic regression to examine the association of both individualized and institutionalized PBD with self-rated health (SRH) after adjustment for individual-level factors such as socioeconomic status (SES). An area-level PBD indicator was created by aggregating individual-level PBD responses in each tract, representing a proxy for institutionalized PBD, i.e., the concept that living in a stigmatized neighborhood affects neighborhood health. 100 tracts were divided into quartiles in order. The health impact of area-level PBD was compared with that of area-level SES indicators (quartile) such as deprivation., Results: After adjustment for individual-level PBD, the highest and third area-level PBD quartiles showed odds ratio (OR) 1.57 (95% credible interval: 1.13-2.18) and 1.38 (0.99-1.92), respectively, for poor SRH compared with the lowest area-level PBD quartile. In a further SES-adjusted model, ORs of area-level PBD (highest and third quartile) were attenuated to 1.32 and 1.31, respectively, but remained marginally significant, although those of the highest area-level not-home-owner (census-based indicator) and deprivation index quartiles were attenuated to 1.26 and 1.21, respectively, and not significant. Individual-level PBD showed significant OR 1.89 (1.33-2.81) for poor SRH in an age, sex, PBD and SES-adjusted model., Conclusion: Institutionalized PBD may be a more important environmental determinant of SRH than other area-level SES indicators such as deprivation. Although it may have a smaller health impact than individualized PBD, attention should be paid to invisible and unconscious aspects of institutionalized PBD to improve residents' health.

We evaluated the ability of platelet-derived growth factor (PDGF) to promote bone augmentation beyond the skeletal envelope in rat calvaria. The calvariae of 14 rats were exposed, and two plastic caps-one with 0.03% PDGF and a chitosan sponge and one with a chitosan sponge alone-were placed. Microcomputed tomography and histologic sections were used to determine the amount of bone augmentation within the plastic caps. Bone volume was calculated using measurement software. Bone volume and amount of bone augmentation were significantly greater in the PDGF group than in the control group. In conclusion, a chitosan sponge containing 0.03% PDGF enhanced bone formation beyond the skeletal envelope in rat calvaria.

Disruption of the Arabidopsis thaliana ACAULIS5 (ACL5) gene, which has recently been shown to encode thermospermine synthase, results in a severe dwarf phenotype. A previous study showed that sac51-d, a dominant suppressor mutant of acl5-1, has a premature termination codon in an upstream open reading frame (ORF) of SAC51, which encodes a putative transcription factor, and suggested the involvement of upstream ORF-mediated translational control in ACL5-dependent stem elongation. Here we report the identification of a gene responsible for sac52-d, another semi-dominant suppressor mutant of acl5-1. SAC52 encodes ribosomal protein L10 (RPL10A), which is highly conserved among eukaryotes and implicated in translational regulation. Transformation of acl5-1 mutants with a genomic fragment containing the sac52-d allele rescued the dwarf phenotype of acl5-1. GUS reporter activity under the control of a SAC51 promoter with its upstream ORF was higher in acl5-1 sac52-d than in acl5-1, suggesting that suppression of the acl5-1 phenotype by sac52-d is attributable, in part, to enhanced translation of certain transcripts including SAC51. We also found that a T-DNA insertion allele of SAC52/RPL10A causes lethality in the female gametophyte.

Background and Objectives: Spinal anesthesia may cause hemodynamic changes due to factors related or not to the patient. The density of the anesthetic compared to the CSF, which interferes with the number of dermatomes blocked and, consequently, with the level of the sympathetic blockade and reduction in blood pressure (BP), is one of those factors. The objective of this study was to evaluate the dispersion of 0.5% hypobaric bupivacaine prepared aseptically in a laboratory, with controlled and uniform density., Methods: Thirty patients, physical status ASA I, II, or III, ages ranging from 18 to 60 years, without cardiovascular comorbidities, who underwent orthopedic surgery of the lower limb, were enrolled in this study. They were sedated with diazepam, 0.03 mg.kg-1, placed in lateral decubitus, with the side to be operated on top. A lumbar puncture in the L3-L4 space was performed with a 27G Quincke needle, and the direction of the bevel and rate of injection were standardized. The sensitive and motor levels (modified Bromage scale) were evaluated., Results: At the end of the surgery, two patients (6.6%) did not present a level 3 motor blockade in the Bromage scale, and the sensitive blockade varied from T4 to T12. Only 12.9% of the patients presented a level of sensitive blockade considered 'high' for the proposed surgery (above T6). The reduction in blood pressure was statistically significant, but it did not fall below 20% of basal levels and, therefore, was not clinically significant. The change in heart rate was non-significant., Conclusions: It was demonstrated that 0.5% hypobaric bupivacaine is a safe choice, with little hemodynamic repercussion in orthopedic surgeries of the lower limbs. The mean duration of the anesthesia, 250 minutes, allows the realization of minor and medium orthopedic procedures.

Lower vertebrates can detect UV light with the pineal complex independently of eyes. Electrophysiological studies, together with chromophore extraction analysis, have suggested that the underlying pigment in the lamprey pineal exhibits a bistable nature, that is, reversible photoreaction by UV and visible light, which is never achieved by known UV pigments. Here we addressed the molecular identification of the pineal UV receptor. Our results showed that the long-hypothesized pigment is a lamprey homologue of parapinopsin, which exhibits an absorption maximum at 370 nm, in the UV region. UV light causes cis-trans isomerization of its retinal(2) chromophore, forming a stable photoproduct having an absorption maximum at 515 nm, in the green region. The photoproduct reverts to the original pigment upon visible light absorption, showing photoregeneration of the pigment. In situ hybridization showed that parapinopsin is selectively expressed in the cells located in the dorsal region of the pineal organ. We successfully obtained the hyperpolarizing responses with a maximum sensitivity of approximately 380 nm from the photoreceptor cells at the dorsal region, in which the outer segment was clearly stained with anti-parapinopsin antibody. These results demonstrated that parapinopsin is the pineal UV pigment having photointerconvertible two stable states. The bistable nature of the parapinopsin can account for the photorecovery of the pineal UV sensitivity by background green light in the lamprey. Furthermore, we isolated the parapinopsin homologues from fish and frog pineal complexes that exhibit UV sensitivity, suggesting that parapinopsin is a common molecular basis for pineal UV reception in the vertebrate.

Osteocyte-like cells were prepared by sequentially treating calvaria from newborn rats with collagenase and chelating agents. On a reconstituted gel of basement membrane components, cells from the third collagenase digest displayed a round shape and expressed the highest level of alkaline phosphatase with minimal osteocalcin deposition into the matrix. On the other hand, cells derived from the interior after EDTA treatment exhibited well-developed dendritic cell processes and expressed essentially no alkaline phosphatase. The latter population also showed quite distinct characteristics such as higher extracellular activities of casein kinase II and ecto-5'-nucleotidase and the extracellular accumulation of a large amount of osteocalcin associated with mineral. These diverse phenotypic and protein expressions as well as the sites from which each population of cells were recovered strongly suggest that we have isolated osteoblastic and osteocytic cells. Bone sialoprotein II was extracellularly phosphorylated by casein kinase II in osteocytic cells but not in osteoblastic cells. We discuss the possibility that differentiation of young osteocytes from osteoblasts may facilitate the biochemical sequence of mineral deposition in the bone matrix.

We have developed a simple and reproducible method employing chemiluminescence to measure oxygen-derived free radicals generated in oxygenated myocardium. Isolated perfused rat hearts were frozen in liquid nitrogen during the control perfusion (non-ischemia), after 30 min of global ischemia (ischemia), or after 20 min of reperfusion following 30-min global ischemia (reperfusion). The frozen hearts were ground to a fine powder and then oxygenated by mixing with phosphate-buffered saline (PBS) (pH 7.4 and PO2 183-194 mmHg) containing lucigenin. The mixed solution was injected into a chemiluminescence detection flow cell. The chemiluminescence intensity increased in relation to the lucigenin and myocardium contents of the test solution. However, it was not affected by the temperature of PBS in the range of 25 degrees C to 50 degrees C. The chemiluminescence intensity of ischemic myocardium was 2.5 times larger than that of non-ischemic or reperfused myocardium (P < 0.01). Recombinant human superoxide dismutase (r-h-SOD) reduced dose-dependently the chemiluminescence intensity induced by oxygenation of ischemic myocardium, while chemically inactivated r-h-SOD did not.