269 research outputs found
GONAD: Genome-editing via Oviductal Nucleic Acids Delivery system: a novel microinjection independent genome engineering method in mice.
Microinjection is considered the gold standard technique for delivery of nucleic acids (NAs; transgenes or genome editing tools such as CRISPR/Cas9 systems) into embryos, for creating genetically modified organisms. It requires sophisticated equipment as well as well-trained and highly skilled personnel to perform the micro-injection technique. Here, we describe a novel and simple microinjection-independent technique, called Genome-editing via Oviductal Nucleic Acids Delivery (GONAD). Using GONAD, we show that NAs (e.g., eGFP mRNA or Cas9 mRNA/sgRNAs) can be effectively delivered to pre-implantation embryos within the intact mouse oviduct by a simple electroporation method, and result in the desired genetic modification in the embryos. Thus GONAD can bypass many complex steps in transgenic technology such as isolation of zygotes, microinjection of NAs into them, and their subsequent transfer to pseudo-pregnant animals. Furthermore, this method can potentially be used for genome editing in species other than mice
A method for determination of gamma-ray direction in space
Gamma-ray bursts (GRBs) are short and most intense bursts of gamma-rays that
come from random direction in space. Their origin are still unknown and they
originate likely from cosmological distances, probably after birth of a new
black hole or death of a giant star. In this work, Geant simulations of a
detector array whose aim is to identify gamma-ray directions in space were
performed and a method for this identification was developed. The array
consists of three quadratic NaI(Tl) scintillators which are facing different
directions and the method is based on the difference of the counts registered
in these three detectors. By using the method the gamma-ray directions are
obtained with 10o accuracy. This form of the array which can scan three
dimensions in space is crucial to pinpoint origin of the GRBs. The array would
also be applicable in various fields where identifications of the gamma-ray
directions are necessary.Comment: 13 pages, 7 figures, 2 table
Differences in muscle power between the dominant and nondominant upper limbs of baseball players
We examined the differences in muscle power between the dominant and nondominant upper limbs of 33 healthy, right-handed, university baseball players (mean age, 20.4±1.1 years) with an average baseball experience >11 years. After measuring maximal voluntary contraction (MVC) of hand grip, elbow flexion, and shoulder internal rotation in both upper limbs, the muscle power of each joint was measured at 40%, 50%, and 60% MVC. No significant differences were observed in the main factors affecting MVC and elbow flexion power loads between dominant and nondominant upper limbs. For handgrip power, load factors at 40% MVC in the dominant hand were lower than those at 60% MVC in the same hand and those at 50% and 60% MVC in the nondominant hand. Significant differences were observed in shoulder internal rotation power between dominant and nondominant upper limbs, with the dominant limb having greater power at all loads. Correlations between muscle power of both upper limbs for handgrip and elbow flexion were significant and moderately high at all loads. For shoulder internal rotation power, the degree of correlation was significant and moderately high at 40% MVC but low to moderate at 50% and 60% MVC. Therefore, baseball players have marked lateral dominance in shoulder internal rotation power unlike handgrip and elbow flexion power, although the relationship between shoulder internal rotation muscle powers of both upper limbs becomes lower with increasing load. The dominance of muscle power of each joint varied even in the same upper limb. It is thus beneficial for baseball players to train with even loads on both arms or adopt simultaneous workout of both arms after adjusting for strength differences. © 2013 National Strength and Conditioning Association
Possible Effects of Pair Echoes on Gamma-Ray Burst Afterglow Emission
High-energy emission from gamma-ray bursts (GRBs) is widely expected but had
been sparsely observed until recently when the Fermi satellite was launched. If
>TeV gamma rays are produced in GRBs and can escape from the emission region,
they are attenuated by the cosmic infrared background photons, leading to
regeneration of GeV-TeV secondary photons via inverse-Compton scattering. This
secondary emission can last for a longer time than the duration of GRBs, and it
is called a pair echo. We investigate how this pair echo emission affects
spectra and light curves of high energy afterglows, considering not only prompt
emission but also afterglow as the primary emission. Detection of pair echoes
is possible as long as the intergalactic magnetic field (IGMF) in voids is
weak. We find (1) that the pair echo from the primary afterglow emission can
affect the observed high-energy emission in the afterglow phase after the jet
break, and (2) that the pair echo from the primary prompt emission can also be
relevant, but only when significant energy is emitted in the TeV range,
typically E_{gamma, >0.1 TeV} > (Y/(1+Y)) epsilon_e E_k. Even non-detections of
the pair echoes could place interesting constraints on the strength of IGMF.
The more favorable targets to detect pair echoes may be the "naked" GRBs
without conventional afterglow emission, although energetic naked GRBs would be
rare. If the IGMF is weak enough, it is predicted that the GeV emission extends
to >30-300 s.Comment: 9 pages, 10 figures, accepted for publication in MNRAS, with extended
description
Rab3a and Rab27b Expression in Nonfunctioning Pituitary Adenomas
Patients with nonfunctioning pituitary adenoma (NFPA) have normal circulating levels of anterior pituitary hormones. Here we examined the expression of exocytic trafficking regulators, Rab27b and Rab3a, in surgically resected pituitary adenoma tissues by immunohistochemical (IHC) analysis using anti-Rab27b and anti-Rab3a antibodies. Among the examined tissues, just over half of the null-cell adenomas and one-third of the gonadotropin-producing adenomas were immunonegative for both Rab27b and Rab3a. However, no Rab-negative samples were observed among the functioning adenomas. These results suggested that downregulated Rab protein expression in anterior pituitary endocrine cells could underlie, at least in part, the hormone-secretion defects of nonfunctioning adenoma cells. Rab27b, Rab3a, and their cellular regulators might therefore be promising pathological markers of patients with NFPA
Clinical Incidence of Sacroiliac Joint Arthritis and Pain after Sacropelvic Fixation for Spinal Deformity
â The authors have no financial conflicts of interest. © Copyright: Yonsei University College of Medicine 2012 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens
Suzaku Observation of the Black Hole Candidate MAXI J1836-194 in a Hard/Intermediate Spectral State
We report on a Suzaku observation of the newly discovered X-ray binary MAXI
J1836-194. The source is found to be in the hard/intermediate spectral state
and displays a clear and strong relativistically broadened iron emission line.
We fit the spectra with a variety of phenomenological, as well as physically
motivated disk reflection models, and find that the breadth and strength of the
iron line is always characteristic of emission within a few gravitational radii
around a black hole. This result is independent of the continuum used and
strongly points toward the central object in MAXI J1836-194 being a stellar
mass black hole rotating with a spin of (90% confidence). We
discuss this result in the context of spectral state definitions, physical
changes (or lack thereof) in the accretion disk and on the potential importance
of the accretion disk corona in state transitions.Comment: 11 pages, 9 Figures, Accepted for publication in Ap
Do Physical Symptoms Predict the Outcome of Surgical Fusion in Patients with Discogenic Low Back Pain?
Study DesignRetrospective case series.PurposeTo determine whether symptoms predict surgical outcomes for patients with discogenic low back pain (DLBP).Overview of LiteratureSpecific diagnosis of DLBP remains difficult. Worsening of pain on flexion is a reported symptom of DLBP. This study sought to determine whether symptoms predict surgical outcomes for patients with DLBP.MethodsWe investigated 127 patients with low back pain (LBP) and no dominant radicular pain. Magnetic resonance imaging was used to select patients with disc degeneration at only one level. If pain was provoked during discography, we performed fusion surgery (87 patients). Visual analogue scale score and responses to a questionnaire regarding symptoms including worsening of pain on flexion or extension were assessed. Symptom sites before surgery were categorized into LBP alone, or LBP plus referred inguinal or leg pain. We followed 77 patients (average 3.0 years) and compared symptoms before surgery with surgical outcome.ResultsSixty-three patients with a good outcome showed postsurgical pain relief (â„60% pain relief) and 14 patients with a poor outcome did not (<60% pain relief). In patients with good outcomes, worsening of LBP was evident in 65% of cases on flexion and in 35% on extension. However, these findings were not significantly different from those in patients with poor outcomes. The percentage of patients with LBP alone was significantly lower and the percentage of patients with LBP plus referred inguinal or leg pain was significantly higher in the group with good surgical outcome compared with patients in the group with poor surgical outcome (p<0.05).ConclusionsWorsening of pain on extension may be a symptom of DLBP. Surgical outcomes were superior in patients with both LBP and either referred inguinal or leg pain compared with those having LBP alone
Existence of a Neuropathic Pain Component in Patients with Osteoarthritis of the Knee
â The authors have no financial conflicts of interest. © Copyright: Yonsei University College of Medicine 2012 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens
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