Successful delayed venous drainage in 16 consecutive distal phalangeal replantations

The authors describe, in the first report of this type of replantation surgery, a high success rate using delayed venous anastomosis in 16 consecutive distal phalangeal replantations under digital block. Among these replantations, seven fingers (43.8 percent) showed postoperative venous congestion and five fingers were reoperated on with delayed venous drainage under digital block. All the reoperated fingers were successfully drained by additional single or double venous drainage with a vein graft. As a result, 13 fingers survived (81.3 percent success rate). All operations were performed under a digital block.     

Automated Software Analysis of Fetal Movement Recorded during a Pregnant Woman’s Sleep at Home

Fetal movement is an important biological index of fetal well-being. Since 2008, we have been developing an original capacitive acceleration sensor and device that a pregnant woman can easily use to record fetal movement by herself at home during sleep. In this study, we report a newly developed automated software system for analyzing recorded fetal movement. This study will introduce the system and compare its results to those of a manual analysis of the same fetal movement signals (Experiment I). We will also demonstrate an appropriate way to use the system (Experiment II). In Experiment I, fetal movement data reported previously for six pregnant women at 28-38 gestational weeks were used. We evaluated the agreement of the manual and automated analyses for the same 10-sec epochs using prevalence-adjusted bias-adjusted kappa (PABAK) including quantitative indicators for prevalence and bias. The mean PABAK value was 0.83, which can be considered almost perfect. In Experiment II, twelve pregnant women at 24-36 gestational weeks recorded fetal movement at night once every four weeks. Overall, mean fetal movement counts per hour during maternal sleep significantly decreased along with gestational weeks, though individual differences in fetal development were noted. This newly developed automated analysis system can provide important data throughout late pregnancy.     

Construction of a Modified Hairpin Ribozyme for Investigations of the Structure-Function Relationship

Abstract

We have constructed a new three domain hairpin ribozyme, in which domain II is connected with domain I' by a helix and a nucleotidic linker to enhance the active bent conformation. The insertion of a nucleotide linker into domain I' increased the cleavage activity more than into domain II. Furthermore, Rev responsive elements (RRE) were introduced in the helix connecting domains. The cleavage activities of the hairpin ribozyme containing the RRE were not affected by the presence of the Rev.     

Single-particle tracking of quantum dot-conjugated prion proteins inside yeast cells

Yeast is a model eukaryote with a variety of biological resources. Here we developed a method to track a quantum dot (QD)-conjugated protein in the budding yeast Saccharomyces cerevisiae. We chemically conjugated QDs with the yeast prion Sup35, incorporated them into yeast spheroplasts, and tracked the motions by conventional two-dimensional or three-dimensional tracking microscopy. The method paves the way toward the individual tracking of proteins of interest inside living yeast cells.     

Evaluation of mental stress by physiological indices derived from finger plethysmography

Background

Quantitative evaluation of mental stress is important to prevent stress-related disorders. Finger plethysmography (FPG) is a simple noninvasive method to monitor peripheral circulation, and provides many physiological indices. Our purpose is to investigate how FPG-derived indices reflect on mental stress, and to clarify any association between these physiological indices and subjective indices of mental stress.

Methods

Thirty-one healthy women (mean age, 22 years ± 2) participated. The participants rested by sitting on a chair for 10 min. They then performed a computerized version of the Stroop color-word conflict test (CWT) for 10 min. Finally, they rested for 10 min. FPG was recorded throughout the experiment. The participants completed a brief form of the Profile of Mood States (POMS) questionnaire before and after the test. Using the FPG data, we conducted chaos analysis and fast Fourier transform analysis, and calculated chaotic attractors, the largest Lyapunov exponent, a high-frequency (HF) component, a low-to-high-frequency (LF/HF) ratio, finger pulse rate and finger pulse wave amplitude.

Results

The HF component decreased and the LF/HF ratio increased significantly during the test (P < 0.01), while the confusion subscale of POMS increased after the test (P < 0.05). During testing, finger pulse rate significantly increased (P < 0.001), and the finger pulse wave amplitude decreased (P < 0.001). The attractor size reduced during testing and returned to a baseline level afterwards. Although the largest Lyapunov exponent showed no significant change during testing, significant negative correlation with the tension-anxiety subscale of POMS was observed at the beginning (P < 0.01). A significant negative correlation between the LF/HF ratio and two subscales was also observed in the beginning and middle of the test (P < 0.05). There were no correlations during the rest periods.

Conclusions

The physiological indices derived from FPG were changed by mental stress. Our findings indicate that FPG is one of the easiest methods to evaluate mental stress quantitatively. In particular, the largest Lyapunov exponent and the LF/HF ratio might be associated with acute mental stress. Farther examination is needed to find any association between the physiological indices and various types of mental stress.     

Myosin phosphatase-targeting subunit 1 controls chromatid segregation

Myosin phosphatase is a heterotrimeric holoenzyme consisting of myosin phosphatase-targeting subunit 1 (MYPT1), a catalytic subunit of PP1Cβ, and a 20-kDa subunit of an unknown function. We have previously reported that myosin phosphatase also controls mitosis, apparently by antagonizing polo-like kinase 1 (PLK1). Here we found that depletion of MYPT1 by siRNA led to precocious chromatid segregation when HeLa cells were arrested at metaphase by a proteasome inhibitor, MG132, or by Cdc20 depletion. Consistently, cyclin B1 and securin were not degraded, indicating that the chromatid segregation is independent of the anaphase-promoting complex/cyclosome. Precocious segregation induced by MYPT1 depletion requires PLK1 activity because a PLK1 inhibitor, BI-2536, blocked precocious segregation. Furthermore, the expression of an unphosphorylatable mutant of SA2 (SCC3 homologue 2), a subunit of the cohesin complex, prevented precocious chromatid segregation induced by MYPT1 depletion. It has been shown that SA2 at centromeres is protected from phosphorylation by PP2A phosphatase recruited by Shugoshin (Sgo1), whereas SA2 along chromosome arms is phosphorylated by PLK1, leading to SA2 dissociation at chromosome arms. Taken together, our results suggest that hyperactivation of PLK1 caused by MYPT1 reduction could override the counteracting PP2A phosphatase, resulting in precocious chromatid segregation. We propose that SA2 at the centromeres is protected by two phosphatases. One is PP2A directly dephosphorylating SA2, and the other is myosin phosphatase counteracting PLK1.     

Genetic diversity of Microcystis cyanophages in two different freshwater environments

Bacteriophages rapidly diversify their genes through co-evolution with their hosts. We hypothesize that gene diversification of phages leads to locality in phages genome. To test this hypothesis, we investigated the genetic diversity and composition of Microcystis cyanophages using 104 sequences of Ma-LMM01-type cyanophages from two geographically distant sampling sites. The intergenetic region between the ribonucleotide reductase genes nrdA and nrdB was used as the genetic marker. This region contains the host-derived auxiliary metabolic genes nblA, an unknown function gene g04, and RNA ligase gene g03. The sequences obtained were conserved in the Ma-LMM01 gene order and contents. Although the genetic diversity of the sequences was high, it varied by gene. The genetic diversity of nblA was the lowest, suggesting that nblA is a highly significant gene that does not allow mutation. In contrast, g03 sequences had many point mutations. RNA ligase is involved in the counter-host’s phage defense mechanism, suggesting that phage defense also plays an important role for rapid gene diversification. The maximum parsimony network and phylogenic analysis showed the sequences from the two sampling sites were distinct. These findings suggest Ma-LMM01-type phages rapidly diversify their genomes through co-evolution with hosts in each location and eventually provided locality of their genomes.     

Palynological record of climate change during the last deglaciation from the Song Hong (Red River) delta, Vietnam

The palynological sequence from core ND-1 on the Song Hong delta in the northern Vietnam reveals the climate change during the last deglaciation. The identified pollen in the core is dominated by Castanopsis (Lithocarpus), Elaeocarpus, Ficus, Piperaceae and Quercus. High percentages of temperate taxa including the conifers Dacrydium, Podocarpus, Pinus, Cupressaceae, Txodiaceae and Cryptomeria, and broad-leaved taxa of Carpinus, Alnus, Juglans, Carya, Ulmus, Fagus, Ilex, Castanea, Quercus, which have a mainly upland distribution, is possibly associated with a lowering of the montane vegetation boundary. On the other hand, intensified river influence can also result in an increase in the temperate allochthonous taxa. After analyzing the magnitude of river influence on pollen assemblages during the sedimentary environment evolution, we extracted the climate information and used this to reconstruct climate change during the last deglaciation. A cooler climate during 14.5-10.9 cal. kyr BP than at present is indicated by higher percentage of temperate types than at present under a similar river influence on the floodplain. The Younger Dryas cooling event is recognized by widely developed grasslands between 12.9 and 11.6 cal. kyr BP, adding to the evidences for this period from both terrestrial and marine records in regions influenced by the East Asian monsoon. Two other cooling periods, 9.4-9.0 cal. kyr BP and 6.5-5.2 cal. kyr BP, are indicated by increases of temperate pollen taxa such as Cryptomeria, Alnus, Quercus, and Castanea.     

Myosin phosphatase-targeting subunit 1 regulates mitosis by antagonizing polo-like kinase 1

Myosin phosphatase-targeting subunit 1 (MYPT1) binds to the catalytic subunit of protein phosphatase 1 (PP1C). This binding is believed to target PP1C to specific substrates including myosin II, thus controlling cellular contractility. Surprisingly, we found that during mitosis, mammalian MYPT1 binds to polo-like kinase 1 (PLK1). MYPT1 is phosphorylated during mitosis by proline-directed kinases including cdc2, which generates the binding motif for the polo box domain of PLK1. Depletion of PLK1 by small interfering RNAs is known to result in loss of gamma-tubulin recruitment to the centrosomes, blocking centrosome maturation and leading to mitotic arrest. We found that codepletion of MYPT1 and PLK1 reinstates gamma-tubulin at the centrosomes, rescuing the mitotic arrest. MYPT1 depletion increases phosphorylation of PLK1 at its activating site (Thr210) in vivo, explaining, at least in part, the rescue phenotype by codepletion. Taken together, our results identify a previously unrecognized role for MYPT1 in regulating mitosis by antagonizing PLK1.     

The development of cysteine proteases in freesia corms during responses to chilling

Freesia protease (FP)-A has been found in regular freesia corms (Kaneda et al., Biosci. Biotechnol. Biochem. 61 (1997) 1554). New corms were generated from original corms that were kept for several months at 4°C. In this study, two proteases (FP-B and FP-C) have been found to new corms kept for 6 months at 4°C, and have increased during new corms enlargement.

 FPs were purified from the extracts of new corms, and the M_r of those were 24k (A), 25k (B), and 24.5k (C) by SDS-PAGE, respectively.

 The N-terminal sequences of FPs were identical to those of papain with respect to the conservative residues of cysteine protease. The sequence of FP-A was identical with those of FP-B within 20 residues of its N-terminal. It may be possible that FP-B was produced by some post-translational modifications from FP-A during the chilling. On the other hand, N-terminal sequence of FP-C was different from those of FP-A and FP-B. It was explained that FP-C was a new protease of freesia corm.