Greatwall phosphorylates an inhibitor of protein phosphatase 2A that is essential for mitosis     

Mochida S  Maslen SL  Skehel M  Hunt T 《Science (New York, N.Y.)》2010,330(6011):1670-1673

Entry into mitosis in eukaryotes requires the activity of cyclin-dependent kinase 1 (Cdk1). Cdk1 is opposed by protein phosphatases in two ways: They inhibit activation of Cdk1 by dephosphorylating the protein kinases Wee1 and Myt1 and the protein phosphatase Cdc25 (key regulators of Cdk1), and they also antagonize Cdk1's own phosphorylation of downstream targets. A particular form of protein phosphatase 2A (PP2A) containing a B55δ subunit (PP2A- B55δ) is the major protein phosphatase that acts on model CDK substrates in Xenopus egg extracts and has antimitotic activity. The activity of PP2A-B55δ is high in interphase and low in mitosis, exactly opposite that of Cdk1. We report that inhibition of PP2A-B55δ results from a small protein, known as α-endosulfine (Ensa), that is phosphorylated in mitosis by the protein kinase Greatwall (Gwl). This converts Ensa into a potent and specific inhibitor of PP2A-B55δ. This pathway represents a previously unknown element in the control of mitosis.  相似文献   

Temperature controls temporal variation in soil CO2 efflux in a secondary beech forest in Appi Highlands, Japan     

Toru Hashimoto  Satoru Miura  Shigehiro Ishizuka 《Journal of Forest Research》2009,14(1):44-50

Forest soil is a huge reserve of carbon in the biosphere. Therefore to understand the carbon cycle in forest ecosystems, it is important to determine the dynamics of soil CO₂ efflux. This study was conducted to describe temporal variations in soil CO₂ efflux and identify the environmental factors that affect it. We measured soil CO₂ efflux continuously in a beech secondary forest in the Appi Highlands in Iwate Prefecture for two years (except when there was snow cover) using four dynamic closed chambers that automatically open after taking measurements. Temporal changes in soil temperature and volumetric soil water content were also measured at a depth of 5 cm. The soil CO₂ efflux ranged from 14 mg CO₂ m⁻² h⁻¹ to 2,329 mg CO₂ m⁻² h⁻¹, the peak occurring at the beginning of August. The relationship between soil temperature and soil CO₂ efflux was well represented by an exponential function. Most of temporal variation in soil CO₂ efflux was explained by soil temperature rather than volumetric soil water content. The Q ₁₀ values were 3.7 ± 0.8 and estimated annual carbon emissions were 837 ± 210 g C m⁻² year⁻¹. These results provide a foundation for further development of models for prediction of soil CO₂ efflux driven by environmental factors.  相似文献   

Effects of row deep tillage for the growth base formed by piling up soil in damp lowlands behind coastal sand dunes to construct coastal disaster prevention forest belts on the Kujukuri coastline,Japan     

Kenji Ono  Akane Komoriya  Ryuichi Tachibana  Akihiro Imaya  Satoru Suzuki  Hironori Noguchi 《Soil Science and Plant Nutrition》2018,64(2):168-180

ABSTRACT

To successfully afforest coastal forest belts ensuring high disaster prevention, growth bases for them have been constructed by piling up soil in the low wetlands along the Kujukuri coastline. Ground surfaces in such bases are often covered with water because of soil compaction, leaving them susceptible to stagnant water. Water stagnation in soil is problematic, potentially interfering with afforesting coastal forests. Therefore, row deep tillage was conducted for parts of growth bases to combat the poor physical properties of the existing soil. Here, we surveyed soil profiles and measured vertical soil hardness distribution in two forest stands with piling up soil to evaluate the effectiveness of tillage for man-made soil. Soil hardness measurements indicated that the vertical areas with ‘soft’ and ‘hard/consolidated’ soil alternately appeared in growth base profiles. Generally, soil of the dense and very hard layers was apt to be formed by strong compaction of the filled-up soil because of heavy machinery usage during growth base preparation. Such dense and hard soils in the untilled areas of the profiles were also observed in this study. By contrast, it was confirmed that row deep tillage drastically improved soil physical properties, i.e., decreased hardness and increased water permeability, because the sequential hardened subsoil layers were well-broken-up. Moreover, it was observed many thick and large roots penetrated deeper layers with deep tillage areas. These results suggest that row deep tillage of hardened soil is quite effective at securing the areas and providing the physical conditions for deeply penetrated roots into deeper soils, which increases healthy root development. They show the effects of soil hardness reduction and water permeability improvement have been maintained for two decades, at least, after construction. These findings will be useful for alleviating some problems of soil compaction, water stagnation, and tree-growth hindrance that have been encountered on afforestation sites with man-made soil.  相似文献   

IMAGING DIAGNOSIS—ECTOPIC SPLEEN MIMICKING HEPATIC TUMOR WITH INTRA‐ABDOMINAL METASTASES INVESTIGATED VIA TRIPLE‐PHASE HELICAL COMPUTED TOMOGRAPHY IN A DOG          下载免费PDF全文

Kenji Kutara  Toshiaki Konno  Hirotaka Kondo  Kotoyo Aoki  Hinako Yamazoe  Satoru Matsunaga 《Veterinary radiology & ultrasound》2017,58(3):E26-E30

A 10‐year‐old castrated male miniature dachshund was presented with an abdominal mass. The dog had a history of splenectomy. Triple‐phase helical computed tomography was utilized, revealing a hepatic mass and multiple intra‐abdominal solid masses. In triple‐phase helical computed tomography the images, hepatic mass and two of four intra‐abdominal masses were heterogenous in all phases. Therefore, we diagnosed a malignant hepatic tumor and presumed intra‐abdominal metastases. The masses were surgically removed and were histologically composed of normal spleen tissues, findings which were consistent with ectopic spleen.  相似文献   

Exposure risk assessment and evaluation of the best management practice for controlling pesticide runoff from paddy fields. Part 1: Paddy watershed monitoring     

Vu SH  Ishihara S  Watanabe H 《Pest management science》2006,62(12):1193-1206

Rice pesticide concentrations in surface water along with hydrological balance and water management conditions were investigated in a paddy watershed of about 100 ha at the Sakura river basin in Tsukuba, Japan, for 3 years from April 2002. Monitoring on different hydrological scales ranging from a paddy plot up to a watershed determined the importance of water management associated with rainfall events and the cyclic irrigation for reducing pesticide discharge into aquatic environments. Surface drainage significantly increased as a response to rainfall events greater than about 1.5 cm day(-1). A total of 16 herbicides were detected in the stream water and their peak concentrations mostly occurred from early to mid-May following the pesticide application period. Two water management factors influencing the pesticide runoff from paddy fields were defined: excess water storage capacity (EWSC) and water holding period (WHP). Uncertainty analyses of pesticide discharge from a paddy plot for dymron (daimuron) and imazosulfuron (IMS) were performed using Monte Carlo simulation (MCS) with prescribed probability of rainfall and water management practice from observations over a period of 3 years. Application of an intermittent irrigation scheme with shallow water depth practice and high drainage gate to maintain the EWSC > 2 cm and increasing WHP from the current Japanese Agricultural Chemicals Regulation law of 3-4 days to at least 10 days were recommended for reducing the pesticide runoff from paddy fields in a monsoon region such as in Japan. The combination of good water management in field plots and small-scale water cycling is the best management practice for controlling pesticide discharge from paddy watersheds.  相似文献   

Prognostic value of magnetic resonance imaging in dogs with paraplegia caused by thoracolumbar intervertebral disk extrusion: 77 cases (2000-2003)     

Ito D  Matsunaga S  Jeffery ND  Sasaki N  Nishimura R  Mochizuki M  Kasahara M  Fujiwara R  Ogawa H 《Journal of the American Veterinary Medical Association》2005,227(9):1454-1460

OBJECTIVE: To determine whether magnetic resonance imaging findings in dogs with paraplegia caused by thoracolumbar intervertebral disk extrusion were predictive of clinical outcome. DESIGN: Retrospective case series. ANIMALS: 77 dogs. PROCEDURE: Medical records and magnetic resonance images were reviewed; clinical outcome was classified as successful (regained ability to walk with no more than mild neurologic deficits) or unsuccessful (severe neurologic deficits persisted). The prognostic value of magnetic resonance imaging was compared with prognostic value of deep pain perception, duration of clinical signs, and rate of onset of clinical signs. RESULT: 33 (43%) dogs had areas of hyperintensity of the spinal cord greater than or equal to the length of the L2 vertebral body on T2-weighted magnetic resonance images. All 44 dogs without areas of hyperintensity on T2-weighted images had a successful outcome, but only 18 of the 33 (55%) dogs with an area of hyperintensity did. Only 5 of 16 dogs with an area of hyperintensity that had also lost deep pain perception had a successful outcome. The odds ratio for an unsuccessful outcome for a dog with an area of hyperintensity (29.87) was higher than the odds ratio for a dog that had lost deep pain perception (5.24). Duration and rate of onset of clinical signs were not associated with clinical outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggest that results of magnetic resonance imaging can be used to predict clinical outcome in dogs with paraplegia caused by intervertebral disk extrusion.  相似文献   

Magnetic resonance imaging of a canine eye with melanoma     

Kato K  Nishimura R  Sasaki N  Matsunaga S  Mochizuki M  Nakayama H  Ogawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(2):179-182

An 8-year-old Beagle dog had exophthalmos of the left eye for the last two past months. On ophthalmoscopy, the intraocular lesion could not be evaluated due to the opacity of the cornea. Ultrasonography revealed that the eyeball was distorted in shape and shifted in position, however, the precise lesion could not be identified. On magnetic resonance (MR) imaging, the lesion was observed as hyperintense on T1-weighted and hypointense on T2-weighted images, similar to those reported in human melanoma. The lesion was histologically diagnosed to be malignant intraocular melanoma. Though this is only a case report, canine ocular melanoma may show the similar characteristic MR images as in human uveal malignant melanoma.  相似文献   

Retrospective seroepidemiological survey for human babesiosis in an area in Japan where a tick-borne disease is endemic     

Arai S  Tsuji M  Kaiho I  Murayama H  Zamoto A  Wei Q  Okabe N  Kamiyama T  Ishihara C 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):335-340

A total of 1,335 archived human sera collected in 1985 from an area in Japan where a tick-borne disease is endemic were examined by indirect immunofluorescence antibody test (IFAT) to estimate seroprevalence against three serologically distinct types of Babesia microti-like parasites; namely, Hobetsu, Kobe, and U.S. types. Eighteen sera (1.3%) were found to be IFAT-positive (titer 1:100-1:6,400), of which 14 and three were ascertained by Western blot analysis to be positive against the Hobetsu and Kobe types, respectively. In addition, four sera showed an IFAT titer of 1:100 against the U.S. type, but they appeared to be false-positive because they were cross-reactive against the Hobetsu and Kobe types, and also because a U.S.-type parasite has not been found in Japan. Our results suggest that human babesiosis in Japan occurred prior to the discovery of the index case in 1999 and that the infections were caused mainly by Hobetsu-type parasites.  相似文献   

Effects of chlorpromazine,pentoxifylline and dexamethasone on mRNA expression of lipopolysaccharide-induced inflammatory cytokines in bovine peripheral blood mononuclear cells     

Kiku Y  Matsuzawa H  Ohtsuka H  Terasaki N  Fukuda S  Kon-Nai S  Koiwa M  Yokomizo Y  Sato H  Rosol TJ  Okada H  Yoshino TO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(8):723-726

The effects of chlorpromazine (CPZ), pentoxifylline (PTX) and dexamethasone (DEX) on mRNA expression of lipopolysaccharide (LPS)-induced proinflammatory cytokines were examined in bovine peripheral blood mononuclear cells (PBMCs) in vitro. The expression of inflammatory cytokine mRNAs was analyzed by RT-PCR and Southern blot hybridization in bovine PBMCs. CPZ and DEX decreased the expression of cytokine mRNA (such as interleukin-1 beta and tumor necrosis factor-alpha) after stimulation with LPS in a dose-dependent manner. However, pretreatment with PTX had no inhibitory effect on the mRNA expression of proinflammatory cytokines. These results indicated that pretreatment with CPZ and DEX might be effective to reduce the production of LPS-induced inflammatory cytokines in bovine PBMCs in vitro.  相似文献   

Inhibitory effects of epigallocatechin gallate on the propagation of bovine coronavirus in Madin-Darby bovine kidney cells     

Mitsuyo MATSUMOTO  Takao MUKAI  Satoru FURUKAWA  Hitoshi OHORI 《Animal Science Journal》2005,76(5):507-512

Epigallocatechin gallate (EGCg) is the main active component of tea polyphenol and shows several biological activities, such as antimicrobial, antitumor‐promoting, anti‐inflammatory and anti‐oxidative activities. In the present study, the inhibitory effect of EGCg on bovine coronavirus (BCV) propagation in Madin‐Darby bovine kidney (MDBK) cells was investigated. EGCg at concentrations of less than 10 µg/mL did not show any cytotoxicity to MDBK cells. BCV propagation was significantly inhibited by pretreatment of the virus with EGCg (0.5–10 µg/mL) before virus inoculation in dose‐dependent, incubation time‐dependent and temperature‐dependent manners. The antiviral effect of pretreating MDBK cells with EGCg on BCV propagation was much weaker than that of pretreating BCV with EGCg. The hemagglutination activity of BCV was also reduced by EGCg in a dose‐dependent manner. These results demonstrate that EGCg possesses a distinct anti‐BCV activity and strongly suggest that EGCg interferes with the adsorption of BCV to MDBK cells by the interaction of EGCg with BCV particles. EGCg may therefore be a useful candidate for controlling BCV infection more effectively.  相似文献