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101.
Objectives It is likely that genetic factors play a role in the etiology of chronic sinusitis, and airway inflammation is an important pathological feature in chronic sinusitis. We hypothesized that individuals with greater inflammatory responses may be more likely to acquire the disease. Polymorphisms of the tumor necrosis factor (TNF) genes have been described, and certain inflammatory diseases are reportedly associated with certain alleles of TNF genes. The purpose of this study is to examine whether there is an association between some alleles of TNF genes and chronic sinusitis. Study Design Thirty‐eight Japanese patients with intractable chronic sinusitis were selected on the basis of the following criteria: 1) persistent mucous or mucopurulent nasal discharge and/or postnasal dripping for longer than 3 years and 2) opacification in bilateral maxillary sinuses and ethmoid cells on plain radiographic films. Methods Both tumor necrosis factor‐α (TNF‐α) and tumor necrosis factor‐β (TNF‐β) gene polymorphisms were analyzed by polymerase chain reaction (PCR) with restriction fragment length polymorphisms in these patients and 35 healthy control subjects. Results A significantly higher frequency (P < .05) of TNFB*2 allele of TNF‐β gene polymorphism was observed in patients with chronic sinusitis (74%) compared with control subjects (56%). There was no association between alleles of TNF‐α and chronic sinusitis. Conclusion We concluded that TNF‐β gene polymorphism may form a component of the genetic predisposition to chronic sinusitis in Japanese patients. 相似文献
102.
Akitaka Yamasaki Kumiko Maruyama-Takahashi Kento Nishida Shogo Okazaki Kouki Okita Yasutoshi Akiyama Hideaki Suzuki Yuichi Endo Kazue Masuko Takashi Masuko Yoshihisa Tomioka 《Genes to cells : devoted to molecular & cellular mechanisms》2023,28(5):374-382
Human epidermal growth factor receptor (HER) family proteins are currently major targets of therapeutic monoclonal antibodies against various epithelial cancers. However, the resistance of cancer cells to HER family-targeted therapies, which may be caused by cancer heterogeneity and persistent HER phosphorylation, often reduces overall therapeutic effects. We herein showed that a newly discovered molecular complex between CD98 and HER2 affected HER function and cancer cell growth. The immunoprecipitation of the HER2 or HER3 protein from lysates of SKBR3 breast cancer (BrCa) cells revealed the HER2-CD98 or HER3-CD98 complex. The knockdown of CD98 by small interfering RNAs inhibited the phosphorylation of HER2 in SKBR3 cells. A bispecific antibody (BsAb) that recognized the HER2 and CD98 proteins was constructed from a humanized anti-HER2 (SER4) IgG and an anti-CD98 (HBJ127) single chain variable fragment, and this BsAb significantly inhibited the cell growth of SKBR3 cells. Prior to the inhibition of AKT phosphorylation, BsAb inhibited the phosphorylation of HER2, however, significant inhibition of HER2 phosphorylation was not observed in anti-HER2 pertuzumab, trastuzumab, SER4 or anti-CD98 HBJ127 in SKBR3 cells. The dual targeting of HER2 and CD98 has potential as a new therapeutic strategy for BrCa. 相似文献
103.
Mitsuhiro Fukao Yuichi Hattori Morio Kanno Ichiro Sakuma Akira Kitabatake 《British journal of pharmacology》1997,120(7):1328-1334
- The aim of the present study was to identify the sources of Ca2+ contributing to acetylcholine (ACh)-induced release of endothelium-derived hyperpolarizing factor (EDHF) from endothelial cells of rat mesenteric artery and to assess the pathway involved. The changes in membrane potentials of smooth muscles by ACh measured with the microelectrode technique were evaluated as a marker for EDHF release.
- ACh elicited membrane hyperpolarization of smooth muscle cells in an endothelium-dependent manner. The hyperpolarizing response was not affected by treatment with 10 μM indomethacin, 300 μM NG-nitro-L-arginine or 10 μM oxyhaemoglobin, thereby indicating that the hyperpolarization is not mediated by prostanoids or nitric oxide but is presumably by EDHF.
- In the presence of extracellular Ca2+, 1 μM ACh generated a hyperpolarization composed of the transient and sustained components. By contrast, in Ca2+-free medium, ACh produced only transient hyperpolarization.
- Pretreatment with 100 nM thapsigargin and 3 μM cyclopiazonic acid, endoplasmic reticulum Ca2+-ATPase inhibitors, completely abolished ACh-induced hyperpolarization. Pretreatment with 20 mM caffeine also markedly attenuated ACh-induced hyperpolarization. However, the overall pattern and peak amplitude of hyperpolarization were unaffected by pretreatment with 1 μM ryanodine.
- In the presence of 5 mM Ni2+ or 3 mM Mn2+, the hyperpolarizing response to ACh was transient, and the sustained component of hyperpolarization was not observed. On the other hand, 1 μM nifedipine had no effect on ACh-induced hyperpolarization.
- ACh-induced hyperpolarization was nearly completely eliminated by 500 nM U-73122 or 200 μM 2-nitro-4-carboxyphenyl-N,N-diphenylcarbamate, inhibitors of phospholipase C, but was unchanged by 500 nM U-73343, an inactive form of U-73122. Pretreatment with 20 nM staurosporine, an inhibitor of protein kinase C, did not modify ACh-induced hyperpolarization.
- These results indicate that the ACh-induced release of EDHF from endothelial cells of rat mesenteric artery is possibly initiated by Ca2+ release from inositol 1,4,5-trisphosphate (IP3)-sensitive Ca2+ pool as a consequence of stimulation of phospholipid hydrolysis due to phospholipase C activation, and maintained by Ca2+ influx via a Ni2+- and Mn2+-sensitive pathway distinct from L-type Ca2+ channels. The Ca2+-influx mechanism seems to be activated following IP3-induced depletion of the pool.
104.
Kamei H Hashimoto Y Koide T Kojima T Hasegawa M Umeda T 《Cancer biotherapy & radiopharmaceuticals》1997,12(5):341-344
Melanoidin, which belongs to the melanin group of molecules, was extracted from the polysaccharide biological response modifier PSK. Melanoidin was cultured together with HCT-15 cells derived from human colon cancer and with AGS cells derived from human gastric carcinoma. After four days of culture, cell count was compared with that of the control cells. Significant suppression was observed, that is, 50% suppression was shown at concentrations of melanoidin between 200 and 100 micrograms/ml. A histogram generated by flow cytometry showed elevation of the tetraploid peak and of that between diploid and tetraploid peaks, suggesting blockage of S phase and G2 to M phase of the cell cycle. Thus, melanoidins contained in the immunomodulator PSK revealed to have a direct tumor cell growth inhibitory effect. 相似文献
105.
Jun Hatazawa Hiroshi Itoh Eku Shimosegawa Iwao Kanno Matsutaroh Murakami Shuichi Miura Hidehiro Iida Toshio Okudera Atsushi Inugami Toshihide Ogawa Hideaki Fujita Yuichi Satoh Ken Nagata Yutaka Hirata Kazuo Uemura 《Annals of nuclear medicine》1994,8(3):213-217
We studied the brain uptake of amino acid in a patient with acute cerebral infarction with L-[2-(F-18)] fluorophenylalanine and positron emission tomography. The increased accumulation of the ligand was specifically found in the peri-infarct area where oxygen metabolism was still maintained but decreased later in the 72-day follow-up period. The kinetic analysis revealed that increased accumulation was not due to increased transport from the blood to the brain but to delayed washout from the brain to the blood. Although the mechanism is still unknown, abnormally high accumulation of L-[F-18]fluorophenylalanine may predict delayed neuronal changes after ischemic insults of the brain. 相似文献
106.
107.
Total Esophagectomy versus Proximal Esophagectomy for Esophageal Cancer at the Cervicothoracic Junction 总被引:1,自引:0,他引:1
Fujita H Kakegawa T Yamana H Sueyoshi S Hikita S Mine T Tanaka Y Ishikawa H Shirouzu K Mori K Inoue Y Tanabe HY Kiyokawa K Tai Y Inutsuka H 《World journal of surgery》1999,23(5):486-491
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic
junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two
groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy
with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy
resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy
compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy
(total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different
between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper
mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or
without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients. 相似文献
108.
Kamei J Kashiwazaki T Taki K Hitosugi H Nagase H 《European journal of pharmacology》1999,369(3):319-323
The duration of the somatostatin-, bradykinin- or prostaglandin F2alpha-induced nociceptive response was significantly less in diabetic mice than in non-diabetic mice. Subcutaneous injection of 7-benzylidenenaltrexone (0.1, 0.3 and 1 mg/kg), an antagonist of delta1-opioid receptors, had no significant effect on either somatostatin-, bradykinin- or prostaglandin F2alpha-induced nociceptive responses in non-diabetic mice. 7-Benzylidenenaltrexone (0.1 and 0.3 mg/kg, s.c.) also had no significant effect on somatostatin- or prostaglandin F2alpha-induced nociceptive responses in diabetic mice. However, the bradykinin-induced nociceptive response in diabetic mice was dose-dependently and significantly increased when 7-benzylidenenaltrexone (0.1, 0.3 and 1 mg/kg, s.c.) was injected 10 min before the injection of bradykinin. These results suggest that a spinal delta1-opioid receptor-mediated endogenous antinociceptive system may inhibit the bradykinin-mediated nociceptive responses in the second phase of the formalin-induced nociceptive response in diabetic mice. 相似文献
109.
We examined the tail-flick response to various heat intensities in diabetic and non-diabetic mice. Heat intensities were set to one of five values by adjusting the source voltage of a 50-W projection bulb to 25, 35, 50, 65 and 80 V. These heat intensities produced surface skin heating rates of 0.1, 0.4, 0.9, 3.0 and 7.3 degrees C/s, respectively. Tail-flick latencies at source voltages of 35 and 50 V in diabetic mice were significantly shorter than those in non-diabetic mice. However, there were no significant differences in tail-flick latencies at 25, 65 and 80 V. In non-diabetic mice, tail-flick latencies were not affected by intrathecal (i.t.) pretreatment with capsaicin 24 h before testing. Tail-flick latencies at 35 and 50 V in diabetic mice were increased by pretreatment with capsaicin. Moreover, although tail-flick latencies in non-diabetic mice were not affected by i.t. pretreatment with calphostin C, a selective protein kinase C inhibitor, those at 35 and 50 V in diabetic mice were increased. However, i.t. pretreatment with (8R, 9S, 11S)-(-)-9-hydroxy-9-n-hexyloxy-carbonyl-8-methyl-2, 3, 9, 10-tetrahydro-8, 11-epoxy-1H, 8H, 11H-2, 7b, 11a-triazadibenzo [a, g]cycloocta[cde]-trinden-1-one (KT5720), a selective protein kinase A inhibitor, did not affect tail-flick latencies in either diabetic or non-diabetic mice. In non-diabetic mice, i.t. pretreatment with phorbol 12,13-dibutyrate (PDB), a protein kinase C activator, decreased tail-flick latencies at 35 and 50 V. Tail-flick latencies in diabetic mice were not affected by i.t. pretreatment with PDB 60 min before testing. Furthermore, the attenuation of tail-flick latencies induced by i.t. pretreatment with PDB in non-diabetic mice was reversed by i.t. pretreatment with capsaicin 24 h before testing. These results indicate that diabetic mice exhibit thermal allodynia and hyperalgesia. Furthermore, this thermal allodynia and hyperalgesia in diabetic mice may be due to the enhanced release of substance P followed by activation of protein kinase C in the spinal cord. 相似文献
110.
Kamei J Ohsawa M Suzuki T Saitoh A Endoh T Narita M Tseng LF Nagase H 《European journal of pharmacology》1999,383(3):241-247
To clarify the pharmacological properties of (+)2-Methyl-4aalpha-(3-hydroxyphenyl)-1, 2, 3, 4, 4a, 5, 12, 12aalpha-octahydro-quinolino[2, 3, 3-g]isoquinoline ((+)-TAN-67), the effect of (+)-TAN-67 on the antinociception induced by the intrathecal (i.t.) administration of nociceptin/orphanin FQ was studied in mice using the tail-flick test and the formalin test. I.t. administration of (+)-TAN-67, at doses of 1 to 10 ng, facilitated the tail-flick response in a dose-dependent manner in mice. In addition, i.t. administration of (+)-TAN-67 (1 to 10 ng) in mice produced a marked pain-like aversive responses. I.t. pretreatment with D-Pro(9)-[spiro-gamma-lactam]-Leu(10)-Trp(11)-physalaemin(1-11) (GR82334, 0.1-1.0 nmol), a potent and selective tachykinin NK(1) receptor antagonist, dose-dependently blocked the reduction of the tail-flick response induced by (+)-TAN-67. Furthermore, (+)-TAN-67-induced facilitation of the tail-flick response was abolished in capsaicin-treated mice. On the other hand, (+)-TAN-67-induced flinching responses were dose-dependently and significantly reduced by i.t. pretreatment with GR82334 (0.1-1.0 nmol). The duration of i.t. (+)-TAN-67-induced flinching responses was significantly reduced in capsaicin-treated mice as compared with naive mice. I.t. administration of nociceptin/orphanin FQ (1-10 nmol) dose-dependently increased the tail-flick latency. I.t. administration of nociceptin/orphanin FQ (0.1-1.0 nmol) significantly and dose-dependently reduced the first-phase nociceptive response, but not the second-phase nociceptive response. I.t. pretreatment with (+)-TAN-67 (0.3-3.0 microg) for 30 min dose-dependently attenuated the antinociception induced by i.t. nociceptin (10 nmol) in the tail-flick test. Furthermore, the antinociceptive effect of nociceptin/orphanin FQ (1 nmol, i.t.) on the first-phase response in the formalin test was dose-dependently attenuated by s.c. pretreatment with (+)-TAN-67 (0.3-3.0 microg). (+)-TAN-67 (0.3-3.0 microg, i.t.), by itself, did not facilitate the tail-flick response or produce apparent behavioral changes. It is possible that (+)-TAN-67 has an antagonistic effect on nociceptin/orphanin FQ-induced antinociception. 相似文献