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81.
The phytochemical investigation of the aerial parts of Tribulus terrestris of Bulgarian origin has resulted in the isolation of the novel furostanol saponin 1, named tribol, together with the known spirostanol saponins 2 and 3 and sitosterol glucoside. The structure of tribol was determined as (25R)-furost-5(6)-ene-3beta,16,26-triol-3-O-alpha-rhamnopyranosyl-(1-->2)-[alpha-rhamnopyranosyl-(1-->4)]-beta-glucopyranoside (1) by spectral analysis, including extensive 1D and 2D-NMR experiments. 相似文献
82.
Kazunori Kuwata Itsuko Nakamura Mika Ide Hiroko Sato Satomi Nishikawa Masaharu Tanaka 《Journal of toxicologic pathology》2015,28(3):151-164
To investigate useful biomarkers associated with proximal tubular injury, we assessed
changes in levels of a focused set of biomarkers in urine and blood. Male rats
administered a single dose or four doses of gentamicin (GM, 240 mg/kg/day) or a single
dose of cisplatin (CDDP, 5 mg/kg) were euthanized on days 2 (the day after initial dosing)
5, or 12. At each time point, histopathological examination of the kidney and
immunohistochemistry for biomarkers, kidney injury molecule-1 (Kim-1), lipocalin (NGAL),
clusterin (CLU), cystatin C (CysC) and β2-microglobulin (β2M) were performed. Biomarker
levels were measured in urine and blood. In both treatment groups, degenerated/necrotic
proximal tubules and regenerated tubules were mainly observed on days 5 and 12,
respectively. At the same time as these tubular injuries, urinary Kim-1, CysC and β2M
levels were increased. Moreover, urinary levels of CysC and β2M in GM-treated animals and
Kim-1 in CDDP-treated animals increased (on day 2) prior to tubular injury on day 5. This
was considered to reflect the characteristics of drug toxicity. Although almost all of the
biomarkers in blood were not sufficiently sensitive to detect proximal tubular injury,
urinary and plasma β2M levels simultaneously increased. Therefore, in addition to urinary
Kim-1, CysC and β2M levels, plasma β2M levels were also considered useful for detecting
proximal tubular injury. 相似文献
83.
The importance of subfragment 2 and C‐terminus of myosin heavy chain for thick filament assembly in skeletal muscle cells 下载免费PDF全文
Koichi Ojima Mika Oe Ikuyo Nakajima Masahiro Shibata Susumu Muroya Koichi Chikuni Akihito Hattori Takanori Nishimura 《Animal Science Journal》2015,86(4):459-467
In skeletal muscle cells, myofibrillar proteins are highly organized into sarcomeres in which thick filaments interdigitate with thin filaments to generate contractile force. The size of thick filaments, which consist mainly of myosin molecules, is strictly controlled. However, little is known about the mechanisms by which myosin molecules assemble into thick filaments. Here, we assessed the ability of each domain of myosin heavy chain (Myh) to form thick filaments. We showed that exogenously expressed subfragment 2 (S2) + light meromyosin (LMM) of Myh was efficiently incorporated into thick filaments in muscle cells, although neither solely expressed S2 nor LMM targeted to thick filaments properly. In nonmuscle COS7 cells, S2+LMM formed more enlarged filaments/speckles than LMM. These results suggest that Myh filament formation is induced by S2 accompanying LMM. We further examined the effects of Myh C‐terminus on thick filament assembly. C‐terminal deletion mutants were incorporated not into entire thick filaments but rather into restricted regions of thick filaments. Our findings suggest that the elongation of myosin filaments to form thick filaments is regulated by S2 as well as C‐terminus of LMM. 相似文献
84.
Endoh K Mochida K Ogonuki N Ohkawa M Shinmen A Ito M Kashiwazaki N Ogura A 《The Journal of reproduction and development》2007,53(6):1199-1206
Assessment of the developmental ability of oocytes following freezing and thawing is an important step for optimizing oocyte cryopreservation techniques. However, the in vitro fertilization of frozen-thawed mouse oocytes is often inefficient because of incomplete capacitation of spermatozoa in the absence of surrounding cumulus cells. This study was undertaken to determine whether the oocyte cryopreservation efficiency of different strains of mice could be assessed from the development of oocytes following parthenogenetic activation and intracytoplasmic sperm injection (ICSI). Oocytes were collected from hybrid (C57BL/6 x DBA/2) F1 or inbred (C57BL/6J, C3H/HeN, DBA/2J and BALB/cA) strains and were vitrified in a solution containing ethylene glycol, DMSO, Ficoll and sucrose. In the first series of experiments, oocytes were activated parthenogenetically by Sr(2+) treatment after warming. The oocytes from the inbred strains, but not those of the F1 hybrid, were diploidized by cytochalasin treatment to obtain a sufficient number of blastocysts. In all strains tested, parthenogenetic embryos derived from vitrified oocytes developed into blastocysts at rates between 23 and 68%. In the second series of experiments, vitrified oocytes from each strain were injected with homologous spermatozoa after warming. Normal offspring were obtained from all strains at rates between 5 and 26% per embryo transferred. Thus, the feasibility of oocyte cryopreservation protocols can be assessed easily by in vitro development of parthenogenetic embryos or by in vivo development of ICSI embryos. Moreover, the oocytes of these four major inbred strains of mice can be cryopreserved safely for production of offspring. 相似文献
85.
Kuwamura M Sawamoto O Yamate J Aoki M Ohnishi Y Kotani T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(5):531-533
A female adult bottlenose dolphin suddenly died at 17 days after the capture. Macroscopically, severe pulmonary congestive edema was found. Histopathology revealed many lungworms in the bronchioli and the worms were identified as Stenurus ovatus. Variously sized vessels proliferated around the lesioned bronchioli. Based on these findings, chronic bronchopneumonia due to the lungworm was diagnosed and vascular proliferation was similar to angiomatosis recently reported in Atlantic bottlenose dolphin. 相似文献
86.
Eduardo Eiji Maeda Barnaby J.F. Clark Petri Pellikka Mika Siljander 《Agricultural Systems》2010,103(9):609-620
The Taita Hills are the northernmost part of the Eastern Arc Mountains of Kenya and Tanzania, which is one of the most important regions for biological conservation in the world. The indigenous cloud forests in this area have suffered substantial degradation for several centuries due to agricultural expansion. In the Taita Hills, currently only 1% of the original forested area remains preserved. In order to create effective policies to preserve the natural resources and biodiversity of the Eastern Arc Mountains it is crucial to understand the causes and interactions involved in the landscape changes in the most degraded areas. The research presented here aimed to understand the role of landscape attributes and infrastructure components as driving forces of agricultural expansion in the Taita Hills. Geospatial technology tools and a landscape dynamic simulation model were integrated to identify and evaluate the driving forces of agricultural expansion and simulate future landscape scenarios. The results indicate that, if current trends persist, agricultural areas will occupy roughly 60% of the study area by 2030. Agricultural expansion will likely take place predominantly in lowlands and foothills throughout the next 20 years, increasing the spatial dependence on distance to rivers and other water bodies. The main factors driving the spatial distribution of new croplands were the distance to markets, proximity to already established agricultural areas and distance to roads. Other driving forces of the agricultural expansion, as well as their implications for natural resources conservation, are discussed. Further studies are necessary to integrate the effects of population pressure and climate change on the sustainability and characteristics of local agricultural systems. 相似文献
87.
Raine Kortet Mika V. M. Laakkonen Jouni Tikkanen Anssi Vainikka Heikki Hirvonen 《Aquaculture Research》2019,50(5):1482-1490
Predator conditioning can be used to improve post‐release antipredator recognition of hatchery‐reared salmonids. However, possible negative stress‐related effects of prolonged predator conditioning on juvenile fish physiology are poorly understood. We studied the effects of prolonged (91 days) predator odour exposure on whole‐body cortisol level and spleen size in six full‐sib families of juvenile hatchery‐bred Arctic charr (Salvelinus alpinus). Chemical cues from water containing charr‐fed pikeperch (Sander lucioperca) were used as the predator exposure stimuli and lakewater was used as a chemical control. Our study revealed that juvenile body cortisol levels post‐predator conditioning were affected by treatment, fish size and their interaction. Importantly, among the smaller (i.e. slowest growing) charr, the predator‐exposed fish had higher cortisol levels than control fish, while the opposite pattern was true for the larger fish. These results suggest that chemical cues from charr‐fed predators induce a prolonged stress response in juvenile charr. As prolonged predation exposure seems to elevate stress levels in a size‐dependent manner, the larger, faster growing fish could possibly have intrinsically lower stress responses to predation threats than smaller, slower growing fish. Possible coupling between stress sensitivity and growth requires further attention due to the likely implications for the management of unintended domestication among captive‐reared salmonids. 相似文献
88.
Chiaki KITA James K. CHAMBERS Mika TANABE Mitsuhiro IRIE Hiroyuki YAMASAKI Kazuyuki UCHIDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):406
Dogs with ovarian papillary adenocarcinoma occasionally present with ascites and/or pleural effusion. These aspirated fluids often contain a large number of cells, and distinction between neoplastic cells and activated mesothelial cells can be difficult. In this study, 7 cases of canine ovarian papillary adenocarcinoma, including 3 with ascites and pleural effusion, were immunohistochemically examined. Ovarian tumor cells were positive for cytokeratin CAM5.2 (CAM5.2), Wilms’ tumor 1 (WT-1) and progesterone receptor (PR) in all 7 cases. A metastatic lesion of the mediastinum in one case was also positive for CAM5.2, WT-1 and PR. Immunohistochemistry on cell blocks obtained from ascites and/or pleural effusion of 2 cases revealed the presence of PR-positive epithelial cells. Whereas, activated mesothelial cells in ascites or pleural effusion collected from dogs without neoplastic lesions were negative for PR. In addition, surface epithelium and subsurface epithelial structures (SES) of normal canine ovaries, that are considered to be the cell of origin for ovarian papillary adenocarcinoma, were also positive for CAM5.2, WT-1 and PR. These results indicate that, together with CAM5.2, WT-1 and PR is a useful diagnostic marker for canine ovarian papillary adenocarcinoma. Expression of PR may be associated with progesterone-dependent nature of canine ovarian papillary adenocarcinoma. 相似文献
89.
Shigeyuki Tajima Takashi Hirashita Kenji Yoshihara Ampan Bhromsiri Mika Nomura 《Soil Science and Plant Nutrition》2013,59(1):241-247
Repetitive extragenic palindromic (REP)-PCR and enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis was applied to the identification and classification of local isolates of 44 Bradyrhizobium japonicum, 7 Sinorhizobium meliloti, 10 Rhizobium leguminosarum strains from Japan and Thai. Using genomic DNA of the 61 strains, both REP and ERIC primers induced reproducible PCR band patterns, although REP-PCR generated more bands and appeared to be more useful for distinguishing the isolates from each other. Using mixed matrix data from both REP- and ERIC-PCR data, it become possible to distinguish all the isolates analyzed in this experiment from each other. When cluster analysis was applied to both PCR matrix data of 44 B. japonicum isolates, only the REP-PCR dendrogram showed a grouping profile corresponding to the exo-polysaccharide phenotype with a exceptions. When the matrix data of R. leguminosarum and S. meliloti were subjected to cluster analysis, S. meliloti appeared to form a different subgroup from R. leguminosarum in the dendrogram of REP-PCR data except for one strain. In the case of ERIC-PCR, isolates of R. leguminosarum from northern Thailand formed a separate subgroup from other R. leguminosarum and S. meliloti which were dispersed in the dendrogram. These data suggest that REP-PCR and ERIC-PCR were effective for the identification of individual isolates even though the isolates showed a wide genetic diversity and the same phenotype. When the data of the local isolates from Japan and Thailand were subjected to cluster analysis, REP- and ERIC-PCR analysis revealed different grouping characteristics. 相似文献
90.
Salomé Menezes Amadeu M. V. M. Soares Lúcia Guilhermino Mika R. Peck 《Water, air, and soil pollution》2010,208(1-4):317-322
This work aimed to determine the sensitivity of acetylcholinesterase (AChE) and glutathione S-transferases (GST) activities of Crangon crangon (L.) to the water-accommodated fraction (WAF) of the fuel oil spilled by the oil tanker Prestige, in order to assess their usefulness as markers for this kind of pollution. Laboratory exposure of shrimps to WAF of weathered Prestige fuel oil showed no significant interference with AChE activity. Significant induction of GST activity was observed, potentially as a result of high concentrations of polycyclic aromatic hydrocarbons. However, these results were only obtained with the higher WAF concentrations tested. It was concluded that AChE and GST activities of C. crangon were not useful biomarkers for short-term exposure to the WAF of fuel oil spilled by the tanker Prestige and carried to the beaches of Galicia (NW Spain). 相似文献