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51.
Electron microscopic examination of the orexin immunoreactivity in the dorsal raphe nucleus 总被引:1,自引:0,他引:1
The ultrastructure and the synaptic relationships of the orexin-A-like immunoreactive fibers in the dorsal raphe nucleus were examined with an immunoelectron microscopic method. At the electron microscopic level, most of the immunoreactive fibers, a varicosity appearance at the light microscopic level, were found as axon terminals. The large dense-cored vesicles contained in the immunoreactive axon terminals were the most intensely immunostained organellae. These axon terminals were often found to make synapses. While the axo-dendritic synapses were usually asymmetric in appearance, the axo-somatic synapses were symmetric. Orexin-A-like immunoreactive processes with no synaptic vesicles were also found. These processes often received asymmetric synapses. With less frequency, the synapses were found between the orexin-like immunoreactive processes. The results suggest that the orexin peptides are stored in the large dense-cored vesicles; the orexin-containing fibers may have influences on the physiological activities of the dorsal raphe nucleus through direct synaptic relationships. 相似文献
52.
Tohno Y Takano Y Tohno S Moriwake Y Minami T Takakura Y Yuri K 《Biological trace element research》2000,74(1):1-9
To elucidate changes of human tendons with aging, the authors studied age-related changes of elements in human Achilles’ tendons
by inductively coupled plasma-atomic emission spectrometry. The subjects consisted of seven men and seven women, ranging in
age from 61 to 97 yr. It was found that the content of calcium increased progressively with aging in the Achilles’ tendons,
whereas the contents of phosphorus and magnesium decreased gradually with aging. The previous investigations demonstrated
that the content of calcium and phosphorus increased progressively with aging in most, but not all, human tissues, except
for the bones. In ligaments, such as the anterior cruciate ligament and the ligament of the head of the femur, which are histologically
similar to the Achilles’ tendon, it was previously found that both the contents of calcium and phosphorus increased with aging
in the ligaments. It should be noted that the content of phosphorus in the Achilles’ tendons decreased during the aging process.
In addition, it was found that there was a very high direct correlation between phosphorus and magnesium contents in the tendons,
but not between calcium and phosphorus contents. 相似文献
53.
Tateyama Y Takano Y Tohno Y Moriwake Y Tohno S Hashimoto M Araki T 《Biological trace element research》2000,74(3):211-221
To show the relationships of calcium accumulation in the thoracic aorta to the other tissues, calcium contents were determined
with a microwave-induced plasma-atomic emission spectrometer on arteries, veins, cartilages, ligaments, and bones. These tissues
were resected from 18 individuals, consisting of 11 men and 7 women who died in the age range 59–91 yr. As thoracic and abdominal
aortas are routinely used for radiographic examination of arterial calcification, they appear to be standard tissues of the
calcium accumulation. The calcium accumulations were determined in the femoral artery, the superior and inferior venae cavae,
the internal jugular vein, cartilages of the articular disk of the temporomandibular joint and the intervertebral disk, both
the ligaments of the anterior cruciate ligament and the ligamentum capitis femoris, and the calcaneus, in contrast with the
thoracic aorta.
As calcium increased in the thoracic aorta, it increased in the femoral artery, the articular disk of the temporomandibular
joint, the intervertebral disk, both ligaments of the anterior cruciate ligament, and the ligamentum capitis femoris, but
it did not increase in veins, such as the superior and inferior venae cavae and the internal jugular vein. In contrast, it
decreased in the calcaneus. 相似文献
54.
A New System for Stringent, High-Titer Vesicular Stomatitis Virus G Protein-Pseudotyped Retrovirus Vector Induction by Introduction of Cre Recombinase into Stable Prepackaging Cell Lines 总被引:3,自引:2,他引:1 下载免费PDF全文
55.
Yumi Moriwake Yoshiyuki Tohno Setsuko Tohno Takeshi Minami Masako Utsumi Fumio Nishiwaki Masa-oki Yamada Hiroshi Yamamoto Yuko Okazaki Tadashi Fujii Yoshinori Takakura 《Biological trace element research》1998,64(1-3):229-235
The relative contents (RCs) of elements in the human menisci from 23 subjects in the age range between 65 and 93 yr were analyzed
by inductively coupled plasma atomic emission spectrometry. The RCs of sulfur, calcium, and phosphorus in menisci increased
progressively until the 80s, being the highest in the 80s, and thereafter decreased. The RCs of magnesium in menisci increased
progressively until the 90s. Regarding the medial and lateral menisci, higher RCs of magnesium and iron, and a lower RC of
phosphorus were found in lateral menisci in comparison with those in medial menisci.
There were sexual differences in the RCs of calcium and phosphorus of medial and lateral menisci. The RCs of calcium and phosphorus
were about 50% higher in women’s menisci than in men’s. Histological examinations showed that structureless mucoid masses
were observed in the menisci, with very high RCs of calcium and phosphorus being detected. 相似文献
56.
Soji Morishita Kochi Takahashi Marito Araki Yumi Hironaka Yoshitaka Sunami Yoko Edahiro Miyuki Tsutsui Akimichi Ohsaka Satoshi Tsuneda Norio Komatsu 《PloS one》2015,10(3)
Detection of the JAK2V617F mutation is essential for diagnosing patients with classical myeloproliferative neoplasms (MPNs). However, detection of the low-frequency JAK2V617F mutation is a challenging task due to the necessity of discriminating between true-positive and false-positive results. Here, we have developed a highly sensitive and accurate assay for the detection of JAK2V617F and named it melting curve analysis after T allele enrichment (MelcaTle). MelcaTle comprises three steps: 1) two cycles of JAK2V617F allele enrichment by PCR amplification followed by BsaXI digestion, 2) selective amplification of the JAK2V617F allele in the presence of a bridged nucleic acid (BNA) probe, and 3) a melting curve assay using a BODIPY-FL-labeled oligonucleotide. Using this assay, we successfully detected nearly a single copy of the JAK2V617F allele, without false-positive signals, using 10 ng of genomic DNA standard. Furthermore, MelcaTle showed no positive signals in 90 assays screening healthy individuals for JAK2V617F. When applying MelcaTle to 27 patients who were initially classified as JAK2V617F-positive on the basis of allele-specific PCR analysis and were thus suspected as having MPNs, we found that two of the patients were actually JAK2V617F-negative. A more careful clinical data analysis revealed that these two patients had developed transient erythrocytosis of unknown etiology but not polycythemia vera, a subtype of MPNs. These findings indicate that the newly developed MelcaTle assay should markedly improve the diagnosis of JAK2V617F-positive MPNs. 相似文献
57.
Mariana Malzoni Furtado Solange Maria Gennari Cassia Yumi Ikuta Anah Tereza de Almeida Jácomo Zenaide Maria de Morais Hilda Fátima de Jesus Pena Grasiela Edith de Oliveira Porfírio Leandro Silveira Rahel Sollmann Gisele Oliveira de Souza Natália Mundim T?rres José Soares Ferreira Neto 《PloS one》2015,10(11)
This study investigated the exposure of jaguar populations and domestic animals to smooth Brucella, Leptospira spp. and Toxoplasma gondii in the Cerrado, Pantanal and Amazon biomes of Brazil. Between February 2000 and January 2010, serum samples from 31 jaguars (Panthera onca), 1,245 cattle (Bos taurus), 168 domestic dogs (Canis lupus familiaris) and 29 domestic cats (Felis catus) were collected and analysed by rose bengal test for smooth Brucella, microscopic agglutination test for Leptospira spp. and modified agglutination test for T. gondii. Cattle populations from all sites (9.88%) were exposed to smooth Brucella, but only one jaguar from Cerrado was exposed to this agent. Jaguars captured in the Cerrado (60.0%) and in the Pantanal (45.5%) were seropositive for different serovars of Leptospira spp., cattle (72.18%) and domestic dogs (13.1%) from the three sites and one domestic cat from Pantanal were also seropositive for the agent. The most prevalent serotype of Leptospira spp. identified in jaguars from the Cerrado (Grippotyphosa) and the Pantanal (Pomona) biomes were distinct from those found in the domestic animals sampled. Jaguars (100%), domestic dogs (38.28%) and domestic cats (82.76%) from the three areas were exposed to T. gondii. Our results show that brucellosis and leptospirosis could have been transmitted to jaguars by domestic animals; and jaguars probably play an important role in the maintenance of T. gondii in nature. 相似文献
58.
A novel factor FLOURY ENDOSPERM2 is involved in regulation of rice grain size and starch quality 总被引:6,自引:0,他引:6
She KC Kusano H Koizumi K Yamakawa H Hakata M Imamura T Fukuda M Naito N Tsurumaki Y Yaeshima M Tsuge T Matsumoto K Kudoh M Itoh E Kikuchi S Kishimoto N Yazaki J Ando T Yano M Aoyama T Sasaki T Satoh H Shimada H 《The Plant cell》2010,22(10):3280-3294
Rice (Oryza sativa) endosperm accumulates a massive amount of storage starch and storage proteins during seed development. However, little is known about the regulatory system involved in the production of storage substances. The rice flo2 mutation resulted in reduced grain size and starch quality. Map-based cloning identified FLOURY ENDOSPERM2 (FLO2), a member of a novel gene family conserved in plants, as the gene responsible for the rice flo2 mutation. FLO2 harbors a tetratricopeptide repeat motif, considered to mediate a protein-protein interactions. FLO2 was abundantly expressed in developing seeds coincident with production of storage starch and protein, as well as in leaves, while abundant expression of its homologs was observed only in leaves. The flo2 mutation decreased expression of genes involved in production of storage starch and storage proteins in the endosperm. Differences between cultivars in their responsiveness of FLO2 expression during high-temperature stress indicated that FLO2 may be involved in heat tolerance during seed development. Overexpression of FLO2 enlarged the size of grains significantly. These results suggest that FLO2 plays a pivotal regulatory role in rice grain size and starch quality by affecting storage substance accumulation in the endosperm. 相似文献
59.
Payo IM Ongkana N Tohno S Azuma C Minami T Moriwake Y Tohno Y 《Biological trace element research》2007,119(2):103-110
To elucidate compositional changes of the arteries with aging, the authors investigated age-related changes of elements in
the splenic and pulmonary arteries, which supplied blood to contractile organs. After ordinary dissection by medical students
at Nara Medical University was finished, the splenic and pulmonary arteries were resected from the subjects, ranging in age
from 58 to 94 years. The element contents were determined by inductively coupled plasma-atomic emission spectrometry. It was
found that a moderate accumulation of Ca and P occurred in the splenic artery with aging, but it hardly occurred in the pulmonary
artery with aging. Regarding the relationship among elements, the finding that there were significant direct correlations
among the contents of Ca, P, Mg, and Na was commonly obtained in both the splenic and pulmonary arteries. The accumulation
of Ca and P in the splenic artery with aging occurred independently of that in the pulmonary artery. Histologic observation
indicated that a major part of Ca deposits was seen in the middle tunica, but not in the internal tunica. Therefore, the calcification
occurring in the splenic artery belonged to middle sclerosis. 相似文献
60.
We previously reported that reduced platelet endogenous antioxidant enzymes activities are related to the low plasma zinc
level in patients with end-stage renal failure (ESRF). In this study, we attempt to evaluate whether dietary zinc deprivation
reduces the activities of endogenous antioxidant and then enhances oxidative stress in the unstimulated platelet of normal
and 5/6 nephrectomized (Nx) rats because increased platelet oxidative stress is suggested to involve in the incidence of thrombotic
and atherosclerotic diseases. Male Sprague–Dawley rats (n = 48) were fed a zinc-deficient diet and deionized distilled water for 1 week to induce reduction of plasma zinc level. Half
of the rats continued on this diet for 4 weeks as zinc-deplete group, and the other half were maintained on the same diet
but with zinc-supplemented water (120 mg/L zinc sulfate solution) to correct the reduction of plasma zinc level as zinc-replete
group. Half of each group underwent 5/6 Nx, while the other half underwent sham operation. Another 12 normal rats were fed
standard rat chow (containing 23.4% protein and 50 ppm zinc) and drank deionized distilled water as normal control rats. In
zinc-deplete rats including sham-operated and 5/6 Nx rats exhibited lower endogenous antioxidant enzymes activities such as
reduced glutathione (GSH), superoxide dismutase (SOD), and glutathione peroxidase (GPX) and higher malondialdehyde (MDA) levels
than normal control rats in the unstimulated platelets. However, in zinc-replete rats including sham-operated and 5/6 Nx rats
have a normal endogenous antioxidant enzymes activity and normal MDA levels in the unstimulated platelets. We suggest that
in uremia, the low plasma zinc level may be a risk factor for thrombotic and atherosclerotic diseases because it reduces the
activities of endogenous antioxidant enzymes and increases oxidative stress in the unstimulated platelet.
Supported by grant 92-117 from Taipei Veterans General Hospital 相似文献