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51.
Genetic Conservation of Hemagglutinin Gene of H9 Influenza Virus in Chicken Population in Mainland China 总被引:1,自引:0,他引:1
The hemagglutinin (HA) genes of 12 H9N2 influenza virus strains isolated from chickens in Mainland China during the period 1995–2002 were genetically analyzed. All the isolates possessed the same amino acid motif -R-S-S-R/G-L- at the cleavage site of HA. Except for the conserved amino acids, as is the case in the other avian influenza viruses, located in the receptor binding site, all of the 12 isolates possessed N at amino acid position 183; A, T, or V at position 190; K at position 137, whereas the representative strains of the other lineage (except Dk/HK/Y280/97-like lineage) virus of H9N2 viruses had H, E, and R at these positions respectively. These could be considered as the partial molecular markers of the H9 viruses isolated from chickens in Mainland China. Phylogenetic analyses showed HA genes of these isolates belonged to that of A/duck/Hong Kong/Y280/97-like virus lineage. No A/quail/Hong Kong/Gl/97-like virus was found in chicken, population since the outbreak of H9N2 influenza in Mainland China in 1992. The available evidence indicates that HA genes of H9 influenza virus circulating in Mainland China during the past years were well conserved. 相似文献
52.
Norepinephrine turnover and concentrations were examined in eight brain regions of amygdala-kindled and yoked control rats. The subjects were killed 2 months after the kindled subjects had exhibited their sixth "stage 4-5" generalized seizure. No significant differences were found in norepinephrine turnover or concentrations between kindled and yoked control rats in any of the brain regions examined. Dopamine turnover and concentrations in brain regions were also unchanged in kindled rats compared with their yoked controls. The data suggest that amygdala kindling does not produce any long-lasting alterations in brain regional catecholamine turnover or concentrations. 相似文献
53.
Kentaro Fujiwara Takanori Ochi Hiroyuki Koga Go Miyano Shogo Seo Tadaharu Okazaki Masahiko Urao Geoffrey J. Lane Risto J. Rintala Atsuyuki Yamataka 《Journal of pediatric surgery》2021,56(7):1136-1140
PurposeTo report the sequelae of and preventive strategies for selected lower urinary tract (LUT) complications, i.e., posterior urethral diverticulum (PUD), intraoperative LUT injuries, postoperative dysuria, and fistula recurrence in male imperforate anus (IA) with rectourethral/rectovesical (RU/RV) fistula after laparoscopy-assisted anorectoplasty (LAARP) or posterior sagittal anorectoplasty (PSARP).Methods153 boys with IA and RU/RV fistula treated 1986–2019 by LAARP (n = 56) or PSARP (n = 97) at two unrelated institutes were studied retrospectively.ResultsAfter mean follow-up of 17.0 years (range: 36.5 days-32.0 years), the overall incidences of LUT complications were: LAARP (6/56; 10.7%); PSARP (7/97; 7.2%); p = 0.55, comprising PUD: LAARP (n = 5), PSARP (n = 0); p = 0.006; injuries: LAARP (n = 0), PSARP (n = 5); p = 0.16; dysuria: LAARP (n = 1), PSARP (n = 1); p>0.999; and recurrence: LAARP (n = 0), PSARP (n = 1); p>0.999. Mean onset of PUD was 5.1 years (range: 1.0–15.1 years). Treatment: PUD: surgery (n = 2/5), conservative (n = 3/5); injuries: intraoperative repair (n = 5/5); dysuria: conservative (n = 2/2), and recurrence: redo PSARP (n = 1/1).ConclusionsStrategies devised to improve dissection accuracy resolved the specific technical issues causing LUT complications (remnant RU fistula dissection in LAARP and blind posterior access in PSARP). Currently, the incidence of new cases of PUD and LUT injuries is zero.Level of Evidence: Level III 相似文献
54.
55.
Wada Takehiko Ishimoto Takuji Nakaya Izaya Kawaguchi Takehiko Sofue Tadashi Shimizu Sayaka Kurita Noriaki Sasaki Sho Nishiwaki Hiroki Koizumi Masahiro Saito Shoji Nishibori Nobuhiro Oe Yuji Yoshida Mai Miyaoka Yoshitaka Akiyama Shin’ichi Itano Yuya Okazaki Masaki Ozeki Takaya Ichikawa Daisuke Oguchi Hideyo Kohsaka Satoshi Kosaka Shiho Kataoka Yuki Shima Hideaki Shirai Sayuri Sugiyama Kazuhiro Suzuki Tomo Son Daisuke Tanaka Tomomi Nango Eishu Niihata Kakuya Nishijima Yoko Nozu Kandai Hasegawa Midori Miyata Rei Yazawa Masahiko Yamamoto Yoshihiro Yamamoto Ryohei Shibagaki Yugo Furuichi Kengo Okada Hirokazu Narita Ichiei 《Clinical and experimental nephrology》2021,25(12):1277-1285
Clinical and Experimental Nephrology - 相似文献
56.
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
57.
Hyaluronic acid: a specific prognostic indicator of hepatic damage in biliary atresia 总被引:11,自引:0,他引:11
Kobayashi H Horikoshi K Yamataka A Yamataka T Okazaki T Lane GJ Miyano T 《Journal of pediatric surgery》1999,34(12):1791-1794
BACKGROUND/PURPOSE: Hepatic fibrosis can progress in biliary atresia (BA) and is associated with capillarization of hepatic sinusoids. The significance of serum hyaluronic acid (HA) as a noninvasive indicator of histological sinusoidal endothelial cell (SEC) damage and hepatic fibrosis in BA, is investigated. METHODS: A total of 28 postoperative BA patients (mean age, 11.0+/-3.7 years) and 20 normal controls (mean age, 10.5+/-2.8 years) were studied. BA patients were divided into group I, good liver function (n = 8); group II, moderate liver dysfunction (n = 10); and group III, severe liver dysfunction (n = 10). Serum HA was determined using a one-step sandwich enzyme immunoassay, and liver histological damage was confirmed immunohistochemically using an antibody against factor VIII-related antigen (FVIIIRAg), which is specific for detecting damaged SEC. RESULTS: Serum HA was significantly higher (P < .0001) in group III (84.6+/-36.5 ng/mL) than in group I (15.9+/-6.9 ng/mL) or group 11 (28.7+/-10.7 ng/mL). Although immunoreactive products of FVIIIRAg were abundant in group III, they were not detected in SEC from group II. CONCLUSION: Serum HA may be of value for monitoring postoperative BA patients as a noninvasive indicator of SEC damage and progressive hepatic fibrosis. 相似文献
58.
Enhanced expression of vascular endothelial growth factor in lungs of newborn infants with congenital diaphragmatic hernia and pulmonary hypertension 总被引:5,自引:1,他引:4 下载免费PDF全文
BACKGROUND: Pulmonary hypoplasia accompanied by pulmonary hypertension resistant to treatment is an important feature of congenital diaphragmatic hernia (CDH). The pathogenesis of the pulmonary vascular abnormalities in CDH remains to be elucidated at the molecular level. Vascular endothelial growth factor (VEGF), an endothelial cell specific mitogen, is known to play a role in pulmonary angiogenesis and vascular remodelling but there are no data on VEGF expression in patients with CDH. METHODS: Necroscopic lung specimens from 21 patients with CDH with lung hypoplasia and from seven age matched control newborn infants without lung hypoplasia were processed for immunohistochemical analysis using affinity purified anti-human VEGF antibodies. All the cases of CDH had pulmonary hypoplasia, indicated by a lung/body weight index of =0.012, and pulmonary hypertension indicated by repeated cardiac ultrasonography. Cellular localisation of VEGF was semiquantitatively analysed using a staining score ranging from 0 (no staining) to 4 (very strong staining). RESULTS: Significantly raised levels of VEGF immunoreactivity were observed in lung specimens from cases of CDH compared with controls. VEGF was detected mainly in the bronchial epithelium and the medial smooth muscle cells of large (>200 microm) and small (<200 microm) pulmonary arteries, the most intense staining being in the medial smooth muscle cells of the small pulmonary arteries. Endothelial cells were positive for VEGF staining in patients with CDH but not in controls. CONCLUSIONS: This is the first study of VEGF expression in newborn infants with CDH. Increased levels of VEGF, especially in the small, pressure regulating pulmonary arteries, point to a potential role in vascular remodelling. This may reflect an unsuccessful attempt by the developing fetus to increase the pulmonary vascular bed in the hypoplastic lungs to alleviate the associated pulmonary hypertension. 相似文献
59.
Supplement of liver enzyme by intestinal and kidney transplants in congenitally enzyme-deficient rat
Gunn rats have a congenital deficiency of bilirubin-uridine diphosphate glucuronyltransferase (B-UDP-GT) activity and are unable to glucuronidate bilirubin in the bile, resulting in unconjugated hyperbilirubinemia. Other than the liver, several organs, including small bowel and kidneys, are known to have B-UDP-GT activity in normal rats. We performed total- or partial-small-bowel transplantation as well as kidney transplantation for Gunn rats in congenic combination and compared the effects of these procedures. Serum total bilirubin (TBil) levels significantly decreased from 7.84 +/- 0.24 mg/dl to 2.19 +/- 0.43 mg/dl 2 weeks after total-small-bowel transplantation (n = 12). Correlation of hyperbilirubinemia was roughly proportional to the length of the transplanted small bowel. There were no difference in metabolic correction between jejunal and ileal transplantation. Serum TBil levels significantly decreased from 7.83 +/- 0.21 mg/dl to 2.24 +/- 0.98 mg/dl 2 weeks after kidney transplantation (n = 5). In conclusion, small-bowel and kidney transplantation were effective in correcting metabolic abnormality in Gunn rats for the period of 4-6 months. Estimated total B-UDP-GT activity supplemented by small-bowel or kidney transplantation was about 1/5-1/4 of the minimal requirement for the complete normalization of serum total bilirubin levels. 相似文献
60.
K Hirata M H Nathanson A D Burgstahler K Okazaki E Mattei M L Sears 《Investigative ophthalmology & visual science》1999,40(9):2046-2053
PURPOSE: Subcellular Ca2+ signaling patterns, such as Ca2+ waves, gradients, and oscillations, are an important aspect of cell regulation, but the molecular basis for these signaling patterns is not understood. Because Ca2+ release patterns differ among isoforms of the inositol 1,4,5-trisphosphate (InsP3) receptor, the relationship between the distribution of these isoforms and subcellular Ca2+ signaling patterns in nonpigmented epithelial (NPE) cells was investigated. METHODS: The distributions of the types I, II, and III InsP3 receptors were determined in NPE cells by immunofluorescence, and subcellular Ca2+ signaling patterns in these cells were examined by confocal line scanning microscopy. RESULTS: The type I InsP3 receptor was concentrated at the basal pole of NPE cells, whereas the type III receptor was localized to the apical pole. The type II InsP3 receptor was not expressed in detectable amounts. Acetylcholine induced increases in Ca2+ that were mediated by InsP3, and these Ca2+ increases began as Ca2+ waves that were initiated at the apical pole, in the region of the type III InsP3 receptor. Acetylcholine occasionally induced sustained or repetitive Ca2+ increases that were prominent at the basal pole, in the region of the type I InsP3 receptor, but only subtle or absent apically. CONCLUSIONS: Because the type I InsP3 receptor is thought to be responsible for repetitive Ca2+ release events, and the type III InsP3 receptor instead is suited to initiate Ca2+ signals, the subcellular distribution of these two isoforms corresponds to the Ca2+ signaling patterns observed in this cell type. Differential subcellular expression of InsP3 receptor isoforms may be an important molecular mechanism by which NPE cells organize their Ca2+ signals in space and time. 相似文献