Distribution, cell volume and extracellular enzyme activities of heterotrophic bacteria near the mouth of Keum River, Korea.

Article信州大学理学部附属諏訪臨湖実験所報告 9: 61-67(1995)departmental bulletin pape

Proto-Model of an Infrared Wide-Field Off-Axis Telescope

We develop a proto-model of an off-axis reflective telescope for infrared wide-field observations based on the design of Schwarzschild-Chang type telescope. With only two mirrors, this design achieves an entrance pupil diameter of 50 mm and an effective focal length of 100 mm. We can apply this design to a mid-infrared telescope with a field of view of 8 deg X 8 deg. In spite of the substantial advantages of off-axis telescopes in the infrared compared to refractive or on-axis reflective telescopes, it is known to be difficult to align the mirrors in off-axis systems because of their asymmetric structures. Off-axis mirrors of our telescope are manufactured at the Korea Basic Science Institute (KBSI). We analyze the fabricated mirror surfaces by fitting polynomial functions to the measured data. We accomplish alignment of this two-mirror off-axis system using a ray tracing method. A simple imaging test is performed to compare a pinhole image with a simulated prediction.Comment: 14 pages, 16 figure

GADOLINIUM CHLORIDE INHIBITION OF RAT HEPATIC MICROSOMAL EPOXIDE HYDROLASE AND GLUTATHIONE S-TRANSFERASE GENE EXPRESSION

ABSTRACT: The effects of gadolinium chloride, a Kupffer cell toxicant, on the constitutive and inducible expression of hepatic microsomal epoxide hydrolase (mEH) and glutathione S-transferase (GST) genes were examined in rats. Northern blot analysis showed that treatment of rats with GdCl 3 caused suppression of mEH and GST gene expression. mEH mRNA levels were decreased in a time-dependent manner after a single injected dose of GdCl 3 (10 mg/kg, iv), resulting in 95, 55, 17, 36, and 69% of the levels in untreated animals at 6, 12, 18, 24, and 48 hr after treatment, respectively. A maximal reduction in GST Ya, Yb1/2, and Yc1 mRNA levels was also noted at 18 hr after treatment with GdCl 3 , followed by a gradual return to levels in untreated rats at later time points. Whereas treatment of rats with thiazole, allyl disulfide, propyl sulfide, oltipraz, or clotrimazole caused 2-13-fold increases in mEH mRNA levels at 18 hr after treatment, concomitant GdCl 3 treatment caused 30-70% reductions in the increases in mEH mRNA levels. The chemical-inducible mRNA levels for GST Ya, Yb1/2, and Yc1 were also significantly inhibited by GdCl 3 at 18 hr after treatment. Rats treated with GdCl 3 (10 mg/kg/day, iv) for 3-5 consecutive days exhibited 40-90% decreases in mEH, GST Ya, and GST Yb1/2 mRNA levels, relative to control, whereas the Yc1 mRNA level was suppressed at early times and returned to levels in untreated animals at day 5 after treatment. The mRNA levels for mEH and GST Ya in rats treated daily with both allyl disulfide (25 mg/kg, po) and GdCl 3 for 3 consecutive days were 20-30% of those in rats treated with allyl disulfide alone. Western immunoblotting showed that mEH and GST Ya protein expression was decreased at 1-3 days after consecutive daily treatment with GdCl 3 . Whereas treatment of rats with GdCl 3 at a dose of 1 mg/kg suppressed constitutive hepatic mEH gene expression by 85% at 18 hr, rats treated with CaCl 2 (10 mg/kg, iv) in combination with GdCl 3 (1 mg/kg, iv) showed 45% suppression of the mEH mRNA level, compared with untreated animals. GdCl 3 -induced suppression was also significantly reversed for GST Ya mRNA by excessive CaCl 2 administration. These results demonstrate that GdCl 3 effectively inhibits constitutive and inducible mEH and GST expression, with decreases in their mRNA levels. GdCl 3 suppression of detoxifying enzyme expression may be associated with its blocking of intracellular Ca 2؉ influx, which affects signaling pathways for the expression of the genes

De novo copy number variations in cloned dogs from the same nuclear donor

BACKGROUND: Somatic mosaicism of copy number variants (CNVs) in human body organs and de novo CNV event in monozygotic twins suggest that de novo CNVs can occur during mitotic recombination. These de novo CNV events are important for understanding genetic background of evolution and diverse phenotypes. In this study, we explored de novo CNV event in cloned dogs with identical genetic background. RESULTS: We analyzed CNVs in seven cloned dogs using the nuclear donor genome as reference by array-CGH, and identified five de novo CNVs in two of the seven clones. Genomic qPCR, dye-swap array-CGH analysis and B-allele profile analysis were used for their validation. Two larger de novo CNVs (5.2 Mb and 338 Kb) on chromosomes X and 19 in clone-3 were consistently validated by all three experiments. The other three smaller CNVs (sized from 36.1 to76.4 Kb) on chromosomes 2, 15 and 32 in clone-3 and clone-6 were verified by at least one of the three validations. In addition to the de novo CNVs, we identified a 37 Mb-sized copy neutral de novo loss of heterozygosity event on chromosome 2 in clone-6. CONCLUSIONS: To our knowledge, this is the first report of de novo CNVs in the cloned dogs which were generated by somatic cell nuclear transfer technology. To study de novo genetic events in cloned animals can help understand formation mechanisms of genetic variants and their biological implications

Therapeutic genome editing for Charcot-marie-tooth disease type 1a

Charcot-Marie-Tooth 1A (CMT1A) is the most common inherited neuropathy without a known therapy, which is caused by a 1.4 Mb duplication on human chromosome 17, which includes the gene encoding the peripheral myelin protein of 22 kDa (PMP22). Overexpressed PMP22 protein from its gene duplication is thought to cause demyelination and subsequently axonal degeneration in the peripheral nervous system (PNS). Here, we targeted regulatory region of human PMP22 to normalize overexpressed PMP22 level in C22 mice, a mouse model of CMT1A harboring multi copies of human PMP22. Direct local intraneural delivery of CRISPR/Cas9 designed to target TATA-box of PMP22 before the onset of disease, downregulates gene expression of PMP22 and preserves both myelin and axons. Notably, the same approach was effective in partial rescue of demyelination even after the onset of disease. Collectively, our data present a potential therapeutic efficacy of CRISPR/Cas9-mediated targeting of regulatory region of PMP22 to treat CMT1A. Please click Additional Files below to see the full abstract

Precise Temperature Mapping of GaN-Based LEDs by Quantitative Infrared Micro-Thermography

A method of measuring the precise temperature distribution of GaN-based light-emitting diodes (LEDs) by quantitative infrared micro-thermography is reported. To reduce the calibration error, the same measuring conditions were used for both calibration and thermal imaging; calibration was conducted on a highly emissive black-painted area on a dummy sapphire wafer loaded near the LED wafer on a thermoelectric cooler mount. We used infrared thermal radiation images of the black-painted area on the dummy wafer and an unbiased LED wafer at two different temperatures to determine the factors that degrade the accuracy of temperature measurement, i.e., the non-uniform response of the instrument, superimposed offset radiation, reflected radiation, and emissivity map of the LED surface. By correcting these factors from the measured infrared thermal radiation images of biased LEDs, we determined a precise absolute temperature image. Consequently, we could observe from where the local self-heat emerges and how it distributes on the emitting area of the LEDs. The experimental results demonstrated that highly localized self-heating and a remarkable temperature gradient, which are detrimental to LED performance and reliability, arise near the p-contact edge of the LED surface at high injection levels owing to the current crowding effect

Eosinophilic Enteritis Presenting as Intussusception in Adult

Eosinophilic gastroenteritis is defined as a disorder that selectively affects the gastrointestinal tract with eosinophil-rich inflammation in the absence of any known causes for eosinophilia. The clinical manifestations vary according to the site of the eosinophilic infiltrated layer of the bowel wall. Eosinophilic enteritis presenting as intussusception in adult has not been previously reported in the literature. Especially, making the diagnosis of intussusception in adults is often difficult due to the variable clinical findings. In our case, the correct diagnosis of intussusception due to eosinophilic enteritis was arrived at rather easily based on the ultrasonography and endoscopic biopsy. The patient was treated with oral prednisolone at 30 mg/day for 7 days, and then the drug was tapered off for 2 months; we didn't perform surgery. He has been asymptomatic for about 1 year after discharge without disease recurrence

The expression of growth factor signaling genes in co-culture IVM

The objective of this study was to determine the expression of growth factor signaling genes in human adiposederived stem cells (ASCs), porcine oocytes, and cumulus during in vitro maturation (IVM). The human ASCs (from 2 young and 2 old donors) were used for the co-culture IVM system. The maturation rate was examined based on polar body extrusion. The expression of the growth factor signaling genes from ASCs, oocytes, and cumulus were measured using qPCR. All data were analyzed using ANOVA followed by Tukey’s test. The expression of the h-IGF1 signaling genes from human ASCs cells showed similar values in all groups and the h-FGF2 expressions were higher in the young donors than the old ones. The p-FGF2, p-FGFR2, and p-TGFβ1 expressions in the oocytes as well as p-IGFR in the cumulus that were co-cultured from the young donors showed higher values than the old and control groups. The apoptotic ratio (p-BAX/p-BCL2) from the oocytes and cumulus in both co-culture groups also showed lower levels than the control (P<0.05). Oocyte maturation rates were significantly increased in all co-cultured groups (Y1 (85.9 ± 2.2%), Y2 (91.2 ± 1.1%), O1 (86.3 ± 1.5%), and O2 (86.5 ± 2.3%)) compared with the control (76.7 ± 1.1%; P<0.05). Although the expression of growth factor signaling genes was varied, young donors’ ASCs might support in vitro maturation beħer than those from old donors