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171.
We examined the local field potential of the hippocampus to monitor brain states during a conditional discrimination task, in order to elucidate the relationship between ongoing brain states and a conditioned motor reflex. Five 10-week-old Wistar/ST male rats underwent a serial feature positive conditional discrimination task in eyeblink conditioning using a preceding light stimulus as a conditional cue for reinforced trials. In this task, a 2-s light stimulus signaled that the following 350-ms tone (conditioned stimulus) was reinforced with a co-terminating 100-ms periorbital electrical shock. The interval between the end of conditional cue and the onset of the conditioned stimulus was 4±1 s. The conditioned stimulus was not reinforced when the light was not presented. Animals successfully utilized the light stimulus as a conditional cue to drive differential responses to the identical conditioned stimulus. We found that presentation of the conditional cue elicited hippocampal theta oscillations, which persisted during the interval of conditional cue and the conditioned stimulus. Moreover, expression of the conditioned response to the tone (conditioned stimulus) was correlated with the appearance of theta oscillations immediately before the conditioned stimulus. These data support hippocampal involvement in the network underlying a conditional discrimination task in eyeblink conditioning. They also suggest that the preceding hippocampal activity can determine information processing of the tone stimulus in the cerebellum and its associated circuits. 相似文献
172.
Kazuta Yanagitani Katsumi Kawahara 《The International Journal of Life Cycle Assessment》2000,5(5):287-290
In the refrigeration and air conditioning industry, technologies to reduce environmental impacts, such as global warming,
ozone-layer depletion, and discharging industrial wastes, are getting much attention nowadays. This paper reports the Life
Cycle Assessment conducted to comparatively analyze two air conditioner units for residential use. One is a traditional type
with HCFC22 being used for its refrigerant and the other is with HFC410A. Because the main focus of this analysis is on the
comparison of the refrigerants, data of the refrigerants used are taken from the actual measurements in their production and
disposal stages. As a result, the ozone layer depleting effect can be eliminated completely by using HFC410A. On the other
hand, the global warming effect doesn’t get reduced extensively by using HFC410A. However, it does so by treating used refrigerants
with a proper waste management. Moreover, it can be proved that using HFC410A reduces environmental impacts in all the other
impact categories assessed, which are acidification, air pollution, water pollution, and energy consumption. To conclude this
case study, replacing HCFC22 with HFC410A for the refrigerant is certainly one of the effective methods for reducing environmental
impacts given by air conditioners. 相似文献
173.
Inhibition of RANKL‐dependent cellular fusion in pre‐osteoclasts by amiloride and a NHE10‐specific monoclonal antibody
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174.
175.
Shinozawa T Mizutani E Tomioka I Kawahara M Sasada H Matsumoto H Sato E 《Molecular reproduction and development》2004,68(3):313-318
In the present study, we examined the developmental ability of enucleated zygotes, MII oocytes, and parthenogenetically activated oocytes at pronuclear stages (parthenogenetic PNs) as recipient cytoplasm for rat embryonic cell nuclear transfer. Enucleated zygotes as recipient cytoplasm receiving two-cell nuclei allowed development to blastocysts, whereas the development of embryos reconstituted with MII oocytes and parthenogenetic PNs was arrested at the two-cell stage. Previous observations in rat two-cell embryos suggested that the distribution of microtubules is involved in two-cell arrest. Therefore, we also examined the distribution of microtubules using immunofluorescence. At the two-cell stage after nuclear transfer into enucleated zygotes, microtubules were distributed homogeneously in the cytoplasm during interphase, and normal mitotic spindles were observed in cleaving embryos from the two- to four-cell stage. In contrast, embryos reconstituted with MII oocytes and parthenogenetic PNs showed aberrant microtubule organization. In enucleated zygotes, fibrous microtubules were distributed homogeneously in the cytoplasm. In contrast, dense microtubules were localized at the subcortical area in the cytoplasm and strong immunofluorescence intensity was observed at the plasma membrane, while very weak intensity was detected in the central part of enucleated MII oocytes. In enucleated parthenogenetic PNs, high-density and fibrous microtubules were distributed in the subcortical and central areas, respectively. Pre-enucleated parthenogenetic PNs also showed lower intensity of microtubule immunofluorescence in the central cytoplasm than zygotes. In conclusion, the results of the present study showed that zygote cytoplasm is better as recipient than MII oocyte and parthenogenetic PNs for rat two-cell embryonic cell nuclear transfer to develop beyond four-cell stage. Furthermore, microtubule organization is involved in the development of reconstituted embryos to overcome the two-cell arrest. 相似文献
176.
Sayantani Chatterjee Ling Y. Lee Rebeca Kawahara Jodie L. Abrahams Barbara Adamczyk Merrina Anugraham Christopher Ashwood Zeynep Sumer‐Bayraktar Matthew T. Briggs Jenny H. L. Chik Arun Everest‐Dass Sarah Frster Hannes Hinneburg Katia R. M. Leite Ian Loke Uwe Mginger Edward S. X. Moh Miyako Nakano Saulo Recuero Manveen K. Sethi Miguel Srougi Kathrin Stavenhagen Vignesh Venkatakrishnan Katherine Wongtrakul‐Kish Simone Diestel Peter Hoffmann Niclas G. Karlsson Daniel Kolarich Mark P. Molloy Michael H. Muders Martin K. Oehler Nicolle H. Packer Giuseppe Palmisano Morten Thaysen‐Andersen 《Proteomics》2019,19(21-22)
While aberrant protein glycosylation is a recognized characteristic of human cancers, advances in glycoanalytics continue to discover new associations between glycoproteins and tumorigenesis. This glycomics‐centric study investigates a possible link between protein paucimannosylation, an under‐studied class of human N‐glycosylation [Man1‐3GlcNAc2Fuc0‐1], and cancer. The paucimannosidic glycans (PMGs) of 34 cancer cell lines and 133 tissue samples spanning 11 cancer types and matching non‐cancerous specimens are profiled from 467 published and unpublished PGC‐LC‐MS/MS N‐glycome datasets collected over a decade. PMGs, particularly Man2‐3GlcNAc2Fuc1, are prominent features of 29 cancer cell lines, but the PMG level varies dramatically across and within the cancer types (1.0–50.2%). Analyses of paired (tumor/non‐tumor) and stage‐stratified tissues demonstrate that PMGs are significantly enriched in tumor tissues from several cancer types including liver cancer (p = 0.0033) and colorectal cancer (p = 0.0017) and is elevated as a result of prostate cancer and chronic lymphocytic leukaemia progression (p < 0.05). Surface expression of paucimannosidic epitopes is demonstrated on human glioblastoma cells using immunofluorescence while biosynthetic involvement of N‐acetyl‐β‐hexosaminidase is indicated by quantitative proteomics. This intriguing association between protein paucimannosylation and human cancers warrants further exploration to detail the biosynthesis, cellular location(s), protein carriers, and functions of paucimannosylation in tumorigenesis and metastasis. 相似文献
177.
Dwarf bamboo species are monocarpic. They flower simultaneously and die after several decades. The type of flowering in the
genus Sasa ranges from sporadic to gregarious. In order to determine whether or not the sporadic flowering of dwarf bamboo is fixed
genetically, we investigated the distribution of clones using eight microsatellite (SSR) loci in a sporadic flowering patch
of Sasa cernua Makino, a major dwarf bamboo species found in central Hokkaido. In May 2006, flowering occurred on 60.5% of living culms
in a 1600 m2 patch. We established a 50 × 10 m study plot in this patch and noted 1267 clumps consisting of 2529 living culms. We investigated
all 1267 clumps and identified six multilocus genotypes as clones using five variable SSR loci. All flowering clumps belonged
to the same clone. On the other hand, non-flowering vegetative clumps were also discovered to be of the same clone. These
data suggest that all flowering culms originated from a single clone of a sporadic flowering patch of S. cernua. Clonal analysis for investigation of sporadic flowering of S. cernua revealed that only a portion of a clone flowers and dies instead of the whole clone. 相似文献
178.
179.
Nobuaki Ito Masako Yokota Shingo Kawahara Chieko Nagaike Yoshihumi Morimura Tadaomi Hirota Takashi Matsunaga 《The Histochemical journal》1995,27(8):620-629
Summary Blood-group-related antigens expressed in papillary carcinomas and other types of neoplasm of the human thyroid glands have
been shown to be carried by poly-N-acetyllactosamines containing a linear domain susceptible to endo-β-galactosidase digestion. To make clear more precisely
the backbone poly-N-acetyllactosamine structures, labelled lectins specific to different types of these structures and specific to core structures
with β1-6GlcNAc branching of N- and O-linked glycoproteins were employed in conjunction with prior endo-β-galactosidase digestion
on formalin-fixed, paraffin-embedded neoplasms of the human thyroid glands. In papillary carcinomas,Datura stramonium agglutinin (DSA) and succinyl wheat germ agglutinin (Suc-WGA) reacted most consistently and frequently with papillary carcinomas
from all the individuals examined. Pokeweed mitogen (PWM) likewise stained the cells of papillary carcinomas from all the
individuals examined, but in some individuals the number of lectin-reactive cells were very small.Lycoperscion esculentum aggultinin (LEA),Solanum tuberosum agglutinin (STA),Phaseolus vulgaris agglutinin L (PHA-L) andArtocarpus integrifolia agglutinin (jacalin) similarly bound to the cancer cells from most of the individuals, and in these cases the number of reactive
cells was usually much more restricted than was the case with DSA or PWM. In adenoma and other types of carcinoma, such as
follicular carcinomas, these lectins specific to poly-N-acetyllactosamine exhibited slight or no reactivity with the cells, whereas PHA-L and jacalin similarly bound to the cells
of adenomas and carcinomas from most of the individuals examined. Prior digestion with endo-β-galactosidase completely eliminated
or markedly reduced the reactivity with PWM and LEA in papillary carcinomas. Reactivity with DSA, Suc-WGA, STA, PHA-L and
jacalin was slightly reduced or not at all affected by enzyme digestion. These results confirmed that poly-N-acetyllactosamine species found in papillary carcinomas are quite different from those in other types of thyroid neoplasm,
suggesting that at least three different types of poly-N-acetyllactosamine, that is, linear unbranched short and long sequences and highly branched ones are produced in these cells. 相似文献
180.
A monoclonal antibody specific for the amino terminal cleavage site of procollagen type I 总被引:5,自引:0,他引:5
H G Foellmer K Kawahara J A Madri H Furthmayr R Timpl L Tuderman 《European journal of biochemistry》1983,134(1):183-189
A monoclonal mouse IgG1 antibody was produced against the aminopropeptide of dermatosparactic sheep procollagen type I by using the hybridoma technique. Radioimmunoassays demonstrated an apparent affinity constant of 10(8) l X mol-1. The antibody reacted with a 19-amino-acid-long sequence spanning the procollagen N-proteinase cleavage site with stronger binding to structures contributed by the aminopropeptide. The antibody showed strong cross-reactions with similar antigens of bovine, human or chick origin but failed to react with the aminopropeptide of procollagen type III. Incubation of chick or sheep procollagen type I with stoichiometric amounts of antibody blocked the release from procollagen molecules of the aminopropeptide by procollagen N-proteinase. Thus, this antibody seems useful for studying various biological problems encountered in the conversion of procollagen. 相似文献