Using molluscan assemblages from paleotsunami deposits to evaluate the influence of topography on the magnitude of late Holocene mega-tsunamis on Ishigaki Island, Japan

Abstract Four ancient tsunami deposits were identified in a trench excavated on Ishigaki Island, Okinawa, Japan. Three of the tsunami deposits (T-I, T-II, and T-IV) consist of calcareous sand beds, whereas the other (T-III, located stratigraphically between T-II and T-IV) consists of boulders. Deposit T-I was caused by a tsunami in 1771. 14C dating, together with the elevations of the landward margins of these sandy tsunami deposits, suggests that tsunamis II and IV were similar in size to the 1771 tsunami, although the influence of local topographic features on the magnitudes of tsunamis has not yet been examined. This study reconstructs the local topographic features by comparing the molluscan assemblages incorporated within the tsunami deposits with those in recent beach deposits. The presence of species that inhabit the intertidal zone in lagoonal settings in all the assemblages indicates that the present-day shallow lagoon has been present off the study area since the occurrence of tsunami T-IV, which supports the previous hypothesis that the magnitudes of the 1771 tsunami and tsunamis II and IV were similar. These molluscan assemblages also suggest that a high relative abundance of large, heavy mollusc shells is a feature of the paleotsunami deposits in the coastal lowlands found along the shallow coral lagoons

Heterologous complementation systems verify the mosaic distribution of three distinct protoporphyrinogen IX oxidase in the cyanobacterial phylum

The pathways for synthesizing tetrapyrroles, including heme and chlorophyll, are well-conserved among organisms, despite the divergence of several enzymes in these pathways. Protoporphyrinogen IX oxidase (PPOX), which catalyzes the last common step of the heme and chlorophyll biosynthesis pathways, is encoded by three phylogenetically-unrelated genes, hemY, hemG and hemJ. All three types of homologues are present in the cyanobacterial phylum, showing a mosaic phylogenetic distribution. Moreover, a few cyanobacteria appear to contain two types of PPOX homologues. Among the three types of cyanobacterial PPOX homologues, only a hemJ homologue has been experimentally verified for its functionality. An objective of this study is to provide experimental evidence for the functionality of the cyanobacterial PPOX homologues by using two heterologous complementation systems. First, we introduced hemY and hemJ homologues from Gloeobacter violaceus PCC7421, hemY homologue from Trichodesmium erythraeum, and hemG homologue from Prochlorococcus marinus MIT9515 into a Delta hemG strain of E. coli. hemY homologues from G. violaceus and T. erythraeum, and the hemG homologue of P. marinus complimented the E. coli strain. Subsequently, we attempted to replace the endogenous hemJ gene of the cyanobacterium Synechocystis sp. PCC6803 with the four PPOX homologues mentioned above. Except for hemG from P. marinus, the other PPOX homologues substituted the function of hemJ in Synechocystis. These results show that all four homologues encode functional PPOX. The transformation of Synechocystis with G. violaceus hemY homologue rendered the cells sensitive to an inhibitor of the HemY-type PPOX, acifluorfen, indicating that the hemY homologue is sensitive to this inhibitor, while the wild-type G. violaceus was tolerant to it, most likely due to the presence of HemJ protein. These results provide an additional level of evidence that G. violaceus contains two types of functional PPOX

Heterologous complementation systems verify the mosaic distribution of three distinct protoporphyrinogen IX oxidase in the cyanobacterial phylum

The pathways for synthesizing tetrapyrroles, including heme and chlorophyll, are well-conserved among organisms, despite the divergence of several enzymes in these pathways. Protoporphyrinogen IX oxidase (PPOX), which catalyzes the last common step of the heme and chlorophyll biosynthesis pathways, is encoded by three phylogenetically-unrelated genes, hemY, hemG and hemJ. All three types of homologues are present in the cyanobacterial phylum, showing a mosaic phylogenetic distribution. Moreover, a few cyanobacteria appear to contain two types of PPOX homologues. Among the three types of cyanobacterial PPOX homologues, only a hemJ homologue has been experimentally verified for its functionality. An objective of this study is to provide experimental evidence for the functionality of the cyanobacterial PPOX homologues by using two heterologous complementation systems. First, we introduced hemY and hemJ homologues from Gloeobacter violaceus PCC7421, hemY homologue from Trichodesmium erythraeum, and hemG homologue from Prochlorococcus marinus MIT9515 into a Delta hemG strain of E. coli. hemY homologues from G. violaceus and T. erythraeum, and the hemG homologue of P. marinus complimented the E. coli strain. Subsequently, we attempted to replace the endogenous hemJ gene of the cyanobacterium Synechocystis sp. PCC6803 with the four PPOX homologues mentioned above. Except for hemG from P. marinus, the other PPOX homologues substituted the function of hemJ in Synechocystis. These results show that all four homologues encode functional PPOX. The transformation of Synechocystis with G. violaceus hemY homologue rendered the cells sensitive to an inhibitor of the HemY-type PPOX, acifluorfen, indicating that the hemY homologue is sensitive to this inhibitor, while the wild-type G. violaceus was tolerant to it, most likely due to the presence of HemJ protein. These results provide an additional level of evidence that G. violaceus contains two types of functional PPOX

Menstrual Cycle Changes Joint Laxity in Females—Differences between Eumenorrhea and Oligomenorrhea

The purpose of this study was to investigate the changes in anterior knee laxity (AKL), stiffness, general joint laxity (GJL), and genu recurvatum (GR) during the menstrual cycle in female non-athletes and female athletes with normal and irregular menstrual cycles. Participants were 19 female non-athletes (eumenorrhea, n = 11; oligomenorrhea, n = 8) and 15 female athletes (eumenorrhea, n = 8; oligomenorrhea, n = 7). AKL was measured as the amount of anterior tibial displacement at 67 N–133 N. Stiffness was calculated as change in (Δ)force/Δ anterior displacement. The Beighton method was used to evaluate the GJL. The GR was measured as the maximum angle of passive knee joint extension. AKL, stiffness, GJL, and GR were measured twice in four phases during the menstrual cycle. Stiffness was significantly higher in oligomenorrhea groups than in eumenorrhea groups, although no significant differences between menstrual cycle phases were evident in female non-athletes. GR was significantly higher in the late follicular, ovulation, and luteal phases than in the early follicular phase, although no significant differences between groups were seen in female athletes. Estradiol may affect the stiffness of the periarticular muscles in the knee, suggesting that GR in female athletes may change during the menstrual cycle

Clin Exp Nephrol

Disease-specific trajectories of renal function in advanced chronic kidney disease (CKD) are not well defined. Here, we compared these trajectories in the estimated glomerular filtration rate (eGFR) by CKD stages. Patients with multiple eGFR measurements during the 5-year preregistration period of the REACH-J study were enrolled. Mean annual eGFR declines were calculated from linear mixed effect models with the adjustment variables of baseline CKD stage, age, sex and the current CKD stage and the level of proteinuria (CKDA1-3). Among 1,969 eligible patients with CKDG3b-5, the adjusted eGFR decline (ml/min/1.73 m/year) was significantly faster in diabetic kidney disease (DKD) patients and polycystic kidney disease (PKD) patients than in patients with other kidney diseases (DKD, - 2.96 ± 0.13; PKD, - 2.82 ± 0.17; and others, - 1.95 ± 0.05, p < 0.01). The declines were faster with higher CKD stages. In DKD patients, the eGFR decline was significantly faster in CKDG5 than CKDG4 (- 4.10 ± 0.18 vs - 2.76 ± 0.20, p < 0.01), while these declines in PKD patients were similar. The eGFR declines in PKD patients were significantly faster than DKD patients in CKDG4 (- 2.92 ± 0.23 vs - 2.76 ± 0.20, p < 0.01) and in CKDA2 (- 3.36 ± 0.35 vs - 1.40 ± 0.26, p < 0.01). Our study revealed the disease-specific annual eGFR declines by CKD stages and the level of proteinuria. Comparing to the other kidney diseases, the declines in PKD patients were getting faster from early stages of CKD. These results suggest the importance of CKD managements in PKD patients from the early stages