Identification and characterization of a matrix protein (PPP-10) in the periostracum of the pearl oyster, Pinctada fucata

AbstractThe periostracum is a layered structure that is formed as a mollusk shell grows. The shell is covered by the periostracum, which consists of organic matrices that prevent decalcification of the shell. In the present study, we discovered the presence of chitin in the periostracum and identified a novel matrix protein, Pinctada fucata periostracum protein named PPP-10. It was purified from the sodium dodecyl sulfate/dithiothreitol-soluble fraction of the periostracum of the Japanese pearl oyster, P. fucata. The deduced amino acid sequence was determined by a combination of amino acid sequence analysis and cDNA cloning. The open reading frame encoded a precursor protein of 112 amino acid residues including a 21-residue signal peptide. The 91 residues following the signal peptide contained abundant Cys and Tyr residues. PPP-10 was expressed on the outer side of the outer fold in the mantle, indicating that PPP-10 was present in the second or third layer of the periostracum. We also determined that the recombinant PPP-10 had chitin-binding activity and could incorporate chitin into the scaffolds of the periostracum. These results shed light on the early steps in mollusk shell formation

Development and reliability of a standard rating system for outcome measurement of foot and ankle disorders I: development of standard rating system

AbstractBackgroundThe aim of this study was to report the five scales comprising the rating system that the Japanese Society for Surgery of the Foot (JSSF) devised (JSSF standard rating system) and the newly offered interpretations and criteria for determinations of each assessment item.MethodsWe produced the new scales for the JSSF standard system by modifying the clinical rating systems established by the American Orthopaedic Foot and Ankle Society (AOFAS scales) and the Japanese Orthopaedic Association’s foot rating scale (JOA scale). We also provided interpretations of each assessment item and the criteria of determinations in the new standard system.ResultsWe improved the ambiguous expressions and content in the conventional standard rating systems so they would be easily understood by Japanese people. The result was five scales in total. Four were designed for use specifically for ankle-hindfoot, midfoot, hallux metatarsophalangeal- interphalangeal, and lesser metatarsophalangeal- ineterphalangeal sites; and the fifth was for the foot and ankle with rheumatoid arthritis. Furthermore, we described interpretations and criteria for determinations with regard to evaluation items in each scale.ConclusionsConventionally, the AOFAS scales or the JOA scale have been separately applied depending on the sites or disorders concerned, but it was often difficult to decide on scores during practical evaluations because of differing expressions in different languages and also because of ambiguity in the interpretation of each evaluation item and in scoring standards as well. JSSF improved these scales and added definite interpretations of evaluation items as well as criteria for the rating (to be reported here in part I). Because these steps were expected to improve the reliability of outcomes assessed by each scale, we examined the reliability in scores of the newly developed scales, which are reported in part II (in this issue)

Development and reliability of a standard rating system for outcome measurement of foot and ankle disorders II: interclinician and intraclinician reliability and validity of the newly established standard rating scales and Japanese Orthopaedic Association rating scale

AbstractBackgroundThis study evaluated the validity and inter- and intraclinician reliability of (1) the Japanese Society of Surgery of the Foot (JSSF) standard rating system for four sites [ankle- hindfoot (AH), midfoot (MF), hallux (HL), and lesser toe (LT)] and the rheumatoid arthritis (RA) foot and ankle scale and (2) the Japanese Orthopaedic Association’s foot rating scale (JOA scale).MethodsClinicians from the same institute independently evaluated participating patients from their institute by two evaluations at a 1- to 4-week interval. Statistical evaluation was as follows. (1) The intraclass correlation coefficient (ICC) was calculated from data collected from at least two examinations of each patient by at least two evaluating clinicians (Data A). (2) Total scores for the two evaluations were determined from the distribution of differences in data between the two evaluations (Data B); each item was evaluated by determining Cohen’s coefficient of agreement. (3) The relation between patient satisfaction and total score was investigated only for patients who underwent surgery (Data C). Spearman’s rank correlation coefficient was obtained.ResultsParticipants were 65 clinicians and 610 patients, including those with disorders of the AH (313), MF (47), HL (153), and LT (50) and those with RA (47). From Data A, the ICC was high for AH and HL by JSSF scales and for AH, MF, and LT by the JOA scale. From Data B, the coefficient showed high validity for both scales for AH, with almost no difference between the two scales; the validity for HL was higher with the JOA scale than with the JSSF scale. From Data C, correlations were significant between patient satisfaction and outcome for AH and HL by the JSSF scales and for AH, HL, and LT by the JOA scale.ConclusionsThe validity of both scales was high. Clinical evaluation of the therapeutic results using these scales would be highly reliable

Attenuated Food Anticipatory Activity and Abnormal Circadian Locomotor Rhythms in Rgs16 Knockdown Mice

Regulators of G protein signaling (RGS) are a multi-functional protein family, which functions in part as GTPase-activating proteins (GAPs) of G protein α-subunits to terminate G protein signaling. Previous studies have demonstrated that the Rgs16 transcripts exhibit robust circadian rhythms both in the suprachiasmatic nucleus (SCN), the master circadian light-entrainable oscillator (LEO) of the hypothalamus, and in the liver. To investigate the role of RGS16 in the circadian clock in vivo, we generated two independent transgenic mouse lines using lentiviral vectors expressing short hairpin RNA (shRNA) targeting the Rgs16 mRNA. The knockdown mice demonstrated significantly shorter free-running period of locomotor activity rhythms and reduced total activity as compared to the wild-type siblings. In addition, when feeding was restricted during the daytime, food-entrainable oscillator (FEO)-driven elevated food-anticipatory activity (FAA) observed prior to the scheduled feeding time was significantly attenuated in the knockdown mice. Whereas the restricted feeding phase-advanced the rhythmic expression of the Per2 clock gene in liver and thalamus in the wild-type animals, the above phase shift was not observed in the knockdown mice. This is the first in vivo demonstration that a common regulator of G protein signaling is involved in the two separate, but interactive circadian timing systems, LEO and FEO. The present study also suggests that liver and/or thalamus regulate the food-entrained circadian behavior through G protein-mediated signal transduction pathway(s)

A Zebrafish Acromegaly Model Elevates DNA Damage and Impairs DNA Repair Pathways

Acromegaly is a pathological condition due to excess growth hormone (GH) secretion. Acromegaly patients exhibit a deterioration of health and many associated complications, such as cardiovascular issues, arthritis, kidney diseases, muscular weakness, and colon cancer. Since these complications are generalized throughout the body, we investigated the effect of GH excess on cellular integrity. Here, we established stable acromegaly model zebrafish lines that overexpress tilapia GH and the red fluorescence protein (RFP) reporter gene for tracking GH gene expression throughout generations, and performed RNA-Seq data analysis from different organs. Intriguingly, heatmap and Expression2Kinases (X2K) analysis revealed the enrichment of DNA damage markers in various organs. Moreover, H2A.X immunostaining analysis in acromegaly zebrafish larvae and the adult acromegaly model brain and muscle showed a robust increase in the number of DNA-damaged cells. Using Gene Set Enrichment Analysis (GSEA), we found that the acromegaly zebrafish model had impaired DNA repair pathways in the liver, such as double-strand break (DSB), homologous recombination repair (HRR), non-homologous end joining (NHEJ), nucleotide excision repair (NER), and translesion synthesis (TLS). Interestingly, the impairment of DNA repair was even more prominent in acromegaly model than in aged zebrafish (three years old). Thus, our study demonstrates that affection of cellular integrity is characteristic of acromegaly

The Effect of S and Mn on the High-temperature Oxidation and Scale Spallation Behavior of Low-carbon Steels

Early-stage oxidation behavior in air of low-carbon steels with and without S and Mn additions was investigated in terms of oxidation kinetics and scale spallation in a temperature range of 900 to 1150°C. S and Mn did not appear to affect the growth rate of oxide scales within the given oxidation time, ~30 min, however it was found that S significantly enhanced oxide scale spallation. Scale spallation occurred only on the S doped steels oxidized at temperatures more than 1000°C when the thickness of oxide scale exceeded about 120 μm. This scale spallation was confirmed to occur during cooling after the given oxidation time. GD-OES analysis revealed that a significant amount of S enrichment occurred at the oxide/steel interface, which was around 1 mass% on 100 ppm S steel after 120 s of oxidation at 1150°C. Such sulfur enrichment was speculated to be due to accumulation of rejected S from surface recession during the high-temperature oxidation. Observation of the steel surface after complete removal of the oxide scale by quenching the steels into liquid nitrogen clearly indicates the formation of eutectic Fe–FeS structure at scale/steel interface, resulting from a liquid phase formation above 1000°C. Formation of sulfide, and therefore a liquid phase at higher temperature, greatly affected oxide scale spallation