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51.
Occurrence of calcitonin-positive C cells within the distal vagal ganglion and the recurrent laryngeal nerve of the chicken 总被引:1,自引:0,他引:1
Y Kameda 《The Anatomical record》1989,224(1):43-54
The chicken ultimobranchial glands are richly supplied with nerve fibers originating from both the main trunk of the vagus nerve and its branch--the recurrent laryngeal nerve. C cells immunoreactive for calcitonin were invariably found in the large nerve bundles distributed throughout the ultimobranchial glands. In addition, these cells were often present within the distal vagal ganglia and the recurrent laryngeal nerves. The frequency of occurrence and the pattern of distribution of the C cells in the distal vagal ganglia and the recurrent laryngeal nerves were determined in chickens of various ages by means of an immunoperoxidase method with anticalcitonin and antineurofilament antisera. The left and right sides of the ultimobranchial region were asymmetrical. The left ultimobranchial gland was in close contact with the vagus nerve trunk, especially with the distal vagal ganglion, but it was separated from the recurrent laryngeal nerve. The right gland contacted the recurrent laryngeal nerves, its medial edge being frequently penetrated by the nerve, but the gland was separated from the distal vagal ganglion. On the left side, C cells were found in 25 out of 39 distal vagal ganglia but they were not distributed in the recurrent laryngeal nerve. On the right side, the cells were present in 28 out of 43 recurrent laryngeal nerves but absent in the distal vagal ganglia. The results indicate that the C cells secreting a hormone calcitonin can enter into nerves, but their occurrence is restricted to the nerves in close proximity to the ultimobranchial glands. Electron microscopic studies revealed that C cells in the nerves received numerous axon clusters enveloped with Schwann cell cytoplasm. Naked axons regarded as axon terminals were found in direct contact with the surface of C cells. They were mainly composed of efferent-type nerve endings showing the accumulation of numerous small clear vesicles and a few large dense-cored vesicles. In addition, C cells were partly covered with the long cytoplasmic processes of Schwann cells and were also in contact with the Schwann cell perikarya. The C cells in nerves appear to be controlled by neural stimulation. 相似文献
52.
Noriaki Kameda Mineyuki Kagesawa Nobuyuki Hiruta Michio Akima Megumi Ohki Tsukasa Matsumoto 《Pathology international》1987,37(2):291-303
A 62-year-old female with primary leiomyosarcoma of the left femur is reported with a review of 21 cases reported in the literature. The resected specimen showed that the tumor extended from the femoral head to the diaphysis for 13cm in length. The tumor showed mainly intramedullary proliferation, but extraosseous growth was also noted at the great trochanter. Microscopic examination revealed well differentiated leiomyosarcoma characterized by interlacing bundles of fusiform cells with eosinophilic cytoplasm and rod-shaped hyperchromatic nuclei. PAP stain of actin on the tumor cells was positive. On electron microscopy, microfilament of 6–8 nm in diameter, dense bodies, plnocytotic vesicles, marginal attachment plate, and basal lamina were noted. The patient died with pulmonary metastasis, 1 year and 7 months after the operation. An autopsy showed metastases in the right pelvic cavity and bilateral lungs, and confirmed the primary site to be the left femur. 相似文献
53.
Liu Y Takahashi S Ogasawara H Seo HG Kawagoe M Hirasawa F Guo N Ueno Y Kameda T Sugiyama T 《Biomedical research (Tokyo, Japan)》2005,26(1):9-14
A novel substance, #675, found from an Streptomyces sp. SM675 culture medium, dose-dependently stimulates the proliferation of human functional liver cell 4 (FLC4). When FLC4 cells were incubated under conditions without fetal bovine serum (FBS), typical features of apoptotic cell death such as shrinkage and nuclear condensation appeared; high molecular weight (HMW) DNA fragments were found; and caspase-3 and poly (ADP-ribose) polymerase (PARP) proteins were cleaved. When FLC4 cells were incubated with #675 and without FBS, the cells grew healthy, no HMW DNA fragments were found, and caspase-3 and PARP cleavage weakened, suggesting that #675 protects FLC4 cells from apoptosis induced by FBS-deprivation. The quantitative reverse-transcribed polymerase chain reaction did not show differences in PARP or Bcl-2 mRNA expression in FLC4 cells incubated with or without #675, indicating other genes may be involved in this anti-apoptosis effect. These results show that #675 enhances FLC4 proliferation via an apoptosis-inhibition pathway, implying potential pharmacological and clinical applications. 相似文献
54.
Objective: To investigate the effects of estrogen on the susceptibility to oxidation of low-density lipoprotein (LDL) and high-density lipoprotein (HDL) in postmenopausal women. Methods: A total of 23 postmenopausal women were treated with 0.625 mg of conjugated equine estrogen daily for 3 months. Blood samples were obtained before and after therapy. Plasma levels of total cholesterol and triglyceride and the concentrations of cholesterol, triglyceride, phospholipid in LDL and HDL were determined enzymatically and the levels of apolipoprotein A-I, A-II in HDL and apolipoprotein B in LDL were measured by turbidimetric immunoassay. The isolated LDL and HDL were incubated at 37°C for 24 h with CuSO4 5 μmol/l and the lipid peroxide concentration of LDL and HDL was measured. Results: Estrogen significantly reduced the plasma level of total cholesterol and significantly increased the plasma level of triglyceride. The LDL concentrations of cholesterol, phospholipid and apolipoprotein B were significantly decreased following estrogen therapy. The triglyceride level of LDL did not change significantly. The HDL concentrations of cholesterol, triglyceride, phospholipid and apolipoprotein A-I and A-II were all significantly elevated after estrogen therapy. Estrogen significantly inhibited the peroxidation of LDL at 50–2000 μg of LDL protein (14.17±4.17–11.49±1.42 nmol/200 μg of LDL protein, P<0.001) and of HDL (4.49±1.74–3.37±1.24 nmol/200 μg of HDL protein, P<0.03) induced by their incubation in the presence of CuSO4. Conclusions: Estrogen inhibited the susceptibility of LDL and HDL to oxidative modification and favorably affected lipid metabolism by reducing the number of LDL particles and increasing the number of HDL particles in plasma that were resistant to oxidation. 相似文献
55.
Naomi Kawano Takaaki Ito Hitoshi Kitamura Tokuhiko Shibagaki Yoichi Kameda Nobuo Nakamura Masayoshi Kanisawa 《Pathology international》1996,46(6):393-398
The α subunit of a GTP-blndlng protein, Go, was investigated in pulmonary neuroendocrine neoplasms and fetal tissues of the lung by an immunohistochemlcal method. Positive immunostaining for the α subunit of Go (Goα) was found predominantly on the cell membrane and found occasionally in the cytoplasm. Typical carcinoids were all positively stained (9/9), and small cell carcinoma showed weaker and less frequent staining (5 positive cases in 10). Atypical carcinoids were variously stained (3/4). The tendency for obvious neuroendocrine differentiation to be immunohistochemically determined in typical carcinoids and not in small cell carcinoma is also true of staining for neuron specific enolase (NSE), chromogranin A (CG-A) and synaptophysin. In the lung, Goα-immunostaining was positive not only in nerve tissues but also in the airway epithelium. In the fetal lung, serial sections immunostained for NSE, CG-A and Goα confirmed that Goα-immunoreactive cells belong to the neuroendocrine cell population. The biological significance of Goα is unclear in normal and neoplastic lung tissues, but Goα is a useful marker of neuroendocrine cells and neoplasms of the lung. 相似文献
56.
Interferon-gamma inhibits transforming growth factor-beta production in human airway epithelial cells by targeting Smads 总被引:8,自引:0,他引:8
57.
Shiroh Miura Kengo Kosaka Ryuta Fujioka Yusuke Uchiyama Tomofumi Shimojo Takuya Morikawa Azusa Irie Takayuki Taniwaki Hiroki Shibata 《European journal of medical genetics》2019,62(3):172-176
Spinocerebellar ataxia 27 (SCA27) is an autosomal dominant SCA caused by variants in the fibroblast growth factor 14 (FGF14) gene. We examined a Japanese SCA patient whose deceased father also suffered from SCA. The patient was a 63-year-old male. He graduated from junior high school but received no further education. The predominant complaint was slowly progressive dysarthria and gait disturbance, which appeared at age 47. He showed pathological saccadic dysmetria, saccadic intrusions into smooth pursuit eye movements, dysarthria, and limb and truncal ataxia. His gait was wide-based but he did not require a walking stick. Limb muscle strength was intact. Deep tendon reflexes were normal or slightly reduced. Pathological reflexes were absent. He demonstrated mildly impaired vibration sense in the lower limbs. There was no urinary dysfunction. Brain MRI showed cerebellar atrophy without brainstem involvement. We first confirmed the absence of repeat expansion in genes known to be responsible for SCAs 1–3, 6–8, 10, 12, 17, 36 and dentatorubral-pallidoluysian atrophy. By exome analysis, we identified a novel heterozygous variant (NM_004115, c.529A>T; Lys177X) in exon 4 of the FGF14 gene. This variant is expected to generate a truncated FGF14 protein lacking the heparin binding sites, those are likely to modify the activity of FGF14. We confirmed the absence of the variant in 502 healthy Japanese individuals by Sanger sequencing. There is no record of the variant in public databases. We conclude that the novel variation in FGF14 is causative for SCA27 in this patient. 相似文献
58.
Yusuke Komiya Makoto Sugiyama Masaru Ochiai Nanako Osawa Yuto Adachi Shugo Iseki Keizo Arihara 《Nutrients》2021,13(4)
Olive oil is a functional food shown to have a variety of bioactive effects. Therefore, we expect it to be a novel functional food with an exercise-mimetic effect on skeletal muscles. This study aimed to investigate the effect of olive oil on the endurance capacity and muscle metabolism in mice. Mice fed a 7% (w/w) olive oil diet for eight weeks showed improved treadmill running endurance and increased intramuscular triacylglycerol (IMTG) accumulation in the gastrocnemius muscle compared to soybean oil diet-fed controls. The increase in running endurance with olive oil intake was independent of the muscle fiber type. To elucidate underlying the mechanism of elevated IMTG levels, we examined the expression levels of the genes related to lipid metabolism. We found that the expression of diacylglycerol O-acyltransferase1 (DGAT1) was significantly upregulated in the muscle of olive oil diet-fed mice. In addition, the olive oil diet-fed mice showed no metabolic impairment or differences in growth profiles compared to the controls. These results suggest that dietary olive oil intake affects muscle metabolism and muscle endurance by increasing energy accumulation. 相似文献
59.
Yusuke Kubo Masae Ikeya Shuhei Sugiyama Rie Takachu Maki Tanaka Takeshi Sugiura Kaori Kobori Makoto Kobori 《Nutrients》2021,13(6)
Quadriceps muscle atrophy following total knee arthroplasty (TKA) can be caused by tourniquet-induced ischemia–reperfusion (IR) injury, which is often accompanied by oxidative stress and inflammatory responses. n-3 long-chain polyunsaturated fatty acids (LCPUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), exert antioxidant and anti-inflammatory effects against IR injury, whereas n-6 LCPUFAs, particularly arachidonic acid (AA), exhibit pro-inflammatory effects and promote IR injury. This study aimed to examine whether preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio are associated with oxidative stress immediately after TKA. Fourteen eligible patients with knee osteoarthritis scheduled for unilateral TKA participated in this study. The levels of serum EPA, DHA, and AA were measured immediately before surgery. Derivatives of reactive oxygen metabolites (d-ROMs) were used as biomarkers for oxidative stress. The preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio were found to be significantly negatively correlated with the serum d-ROM levels at 96 h after surgery, and the rate of increase in serum d-ROM levels between baseline and 96 h postoperatively. This study suggested the preoperative serum EPA + DHA levels and the (EPA + DHA)/AA ratio can be negatively associated with oxidative stress immediately after TKA. 相似文献
60.