794 research outputs found
EXAFS Study on Local Structure of Iron Crystal by the Use of Asymmetrical Monochromator and PSPC
The EXAFS spectroscopy equipment constructed from an asymmetrical cut flat monochromator and PSPC is applied to the structural determination of pure α-iron which has small difference (0.038nm) in the first and second nearest neighbour distance. The efficiency of the curve fitting method for the two shell model of known structure material (α-iron) is discussed, in addition to describing the details of the experimental procedure of our new type of spectrometer and of the EXAFS data analysis
Gill transcriptome response to changes in environmental calcium in the green spotted puffer fish
Abstract Background Calcium ion is tightly regulated in body fluids and for euryhaline fish, which are exposed to rapid changes in environmental [Ca2+], homeostasis is especially challenging. The gill is the main organ of active calcium uptake and therefore plays a crucial role in the maintenance of calcium ion homeostasis. To study the molecular basis of the short-term responses to changing calcium availability, the whole gill transcriptome obtained by Super Serial Analysis of Gene Expression (SuperSAGE) of the euryhaline teleost green spotted puffer fish, Tetraodon nigroviridis, exposed to water with altered [Ca2+] was analysed. Results Transfer of T. nigroviridis from 10 ppt water salinity containing 2.9 mM Ca2+ to high (10 mM Ca2+ ) and low (0.01 mM Ca2+) calcium water of similar salinity for 2-12 h resulted in 1,339 differentially expressed SuperSAGE tags (26-bp transcript identifiers) in gills. Of these 869 tags (65%) were mapped to T. nigroviridis cDNAs or genomic DNA and 497 (57%) were assigned to known proteins. Thirteen percent of the genes matched multiple tags indicating alternative RNA transcripts. The main enriched gene ontology groups belong to Ca2+ signaling/homeostasis but also muscle contraction, cytoskeleton, energy production/homeostasis and tissue remodeling. K-means clustering identified co-expressed transcripts with distinct patterns in response to water [Ca2+] and exposure time. Conclusions The generated transcript expression patterns provide a framework of novel water calcium-responsive genes in the gill during the initial response after transfer to different [Ca2+]. This molecular response entails initial perception of alterations, activation of signaling networks and effectors and suggests active remodeling of cytoskeletal proteins during the initial acclimation process. Genes related to energy production and energy homeostasis are also up-regulated, probably reflecting the increased energetic needs of the acclimation response. This study is the first genome-wide transcriptome analysis of fish gills and is an important resource for future research on the short-term mechanisms involved in the gill acclimation responses to environmental Ca2+ changes and osmoregulation.Peer Reviewe
Comparison of the Residual Amount of an Ophthalmic Viscosurgical Device Among Different Types of Intraocular Lens Implants in vitro
Tetsutaro Oki, Hiroshi Horiguchi, Ryo Terauchi, Hisato Gunji, Tadashi Nakano Department of Ophthalmology, The Jikei University School of Medicine, Minatoku, Tokyo, 105-8461, JapanCorrespondence: Tetsutaro Oki, Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8, Nishi-shinbashi, Minatoku, Tokyo, 105-8461, Japan, Email [email protected]: Although ophthalmic viscosurgical devices are quite important for safe cataract surgery, currently, postoperative residual ophthalmic viscosurgical devices can cause various complications. Previously, we developed a method to visualize residual ophthalmic viscosurgical devices after irrigation/aspiration in vitro and found that the amount of residual ophthalmic viscosurgical device on a single-piece intraocular lens was greater than that on a three-piece intraocular lens. In the present study, we compared the amounts of residual ophthalmic viscosurgical device among various foldable intraocular lenses to investigate the factors that determine the quantity of residual ophthalmic viscosurgical device.Patients and Methods: Simulated cataract surgery was performed in pig eyes using an ophthalmic viscosurgical device labeled with fluorescent silica particles. After the simulated surgery procedure, the fluorescent silica attached to the intraocular lens was observed and quantified by inductively coupled plasma-atomic emission spectrometry after intraocular lens removal. The amount of residual ophthalmic viscosurgical device was compared among five representative single-piece intraocular lenses and one three-piece intraocular lens.Results: The distribution and amount of the residual ophthalmic viscosurgical device differed for each intraocular lens. The amount of silicon in the lens capsule differed among the intraocular lens types.Conclusion: The postoperative residual tendency of ophthalmic viscosurgical devices differed among various single-piece intraocular lenses. The behavior of the intraocular lenses within the capsule affected the residual tendency. The removal of ophthalmic viscosurgical device in the lens capsule should be tailored for each intraocular lens to improve efficiency.Keywords: cataract surgery, intraocular lens, ophthalmic viscosurgical device
Development of genomic simple sequence repeat markers for yam
Yam (
Dioscorea
spp.) is a major staple crop
widely cultivated for its starchy tubers. To date,
very few marker resources are publicly avail
-
able as tools for genetic and genomic studies of
this economically important crop. In this study,
90 simple sequence repeat (SSR) markers were
developed from an enriched genomic library of
yellow Guinea yam (
D. cayenensis
Lam.). Cross-
amplification revealed that 85 (94.4%) and 51
(56.7%) of these SSRs could be successfully
transferred to the two major cultivated species
of
D. rotundata
Poir. and
D. alata
L., respec
-
tively. Polymorphisms in 30 markers selected
on the basis of reliability and reproducibility of
DNA bands were evaluated using a panel of 12
D. cayenensis
, 48
D. rotundata
, and 48
D. alata
accessions. Accordingly, number of alleles
per locus ranged from 2 to 8 in
D. cayenensis
(mean = 3.9), 3 to 30 in
D. rotundata
(mean =
13.9), and 2 to 22 in
D. alata
(mean = 12.1). The
average observed and expected heterozygosi
-
ties were 0.156 and 0.634 (
D. cayenensis
), 0.326
and 0.853 (
D. rotundata
), and 0.247 and 0.836
(
D. alata
), respectively. Clustering based on six
SSRs that were polymorphic in at least four of
the five cultivated
Dioscorea
species studied,
including
D. cayenensis
,
D. rotundata
,
D. alata
,
D. dumetorum
(Kunth) Pax., and
D. bulbifera
L.,
detected groups consistent with the phyloge
-
netic relationships of the species except for
D.
dumetorum
. These new SSR markers are invalu
-
able resources for applications such as genetic
diversity analysis and marker-assisted breedingYam (
Dioscorea
spp.) is a major staple crop
widely cultivated for its starchy tubers. To date,
very few marker resources are publicly avail
-
able as tools for genetic and genomic studies of
this economically important crop. In this study,
90 simple sequence repeat (SSR) markers were
developed from an enriched genomic library of
yellow Guinea yam (
D. cayenensis
Lam.). Cross-
amplification revealed that 85 (94.4%) and 51
(56.7%) of these SSRs could be successfully
transferred to the two major cultivated species
of
D. rotundata
Poir. and
D. alata
L., respec
-
tively. Polymorphisms in 30 markers selected
on the basis of reliability and reproducibility of
DNA bands were evaluated using a panel of 12
D. cayenensis
, 48
D. rotundata
, and 48
D. alata
accessions. Accordingly, number of alleles
per locus ranged from 2 to 8 in
D. cayenensis
(mean = 3.9), 3 to 30 in
D. rotundata
(mean =
13.9), and 2 to 22 in
D. alata
(mean = 12.1). The
average observed and expected heterozygosi
-
ties were 0.156 and 0.634 (
D. cayenensis
), 0.326
and 0.853 (
D. rotundata
), and 0.247 and 0.836
(
D. alata
), respectively. Clustering based on six
SSRs that were polymorphic in at least four of
the five cultivated
Dioscorea
species studied,
including
D. cayenensis
,
D. rotundata
,
D. alata
,
D. dumetorum
(Kunth) Pax., and
D. bulbifera
L.,
detected groups consistent with the phyloge
-
netic relationships of the species except for
D.
dumetorum
. These new SSR markers are invalu
-
able resources for applications such as genetic
diversity analysis and marker-assisted breedin
- …