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21.
The structure of the avian fast skeletal muscle troponin T gene: seven novel tandem-arranged exons in the exon x region 总被引:1,自引:0,他引:1
Miyazaki J Jozaki M Nakatani N Watanabe T Saba R Nakada K Hirabayashi T Yonemura I 《Journal of muscle research and cell motility》1999,20(7):655-660
To elucidate the mechanism that produces enormous molecular diversity in troponin T (TnT) of fast skeletal muscle, we determined the 5-half genomic sequence of the chicken fast muscle TnT gene. The sequence of ca. 16 kb included seven exons (exons 1, 2, 3, 4, w, 5, and 6), which have been reported previously and presumed by sequencing TnT cDNAs. Additionally we found six 15 nt and one 18 nt sequences in the region between exons 5 and 6 (i.e. the exon x region). They were encompassed by consensus splice donor and acceptor sites and preceded by putative branch sites, and designated herein as exons xa to xg. Our result shows that the sequence derived from exons x1, x2, and x3, the exons presumed previously by cDNA sequencing, is actually encoded by the seven exons xa to xg, establishing the precise gene structure in the exon x region. Based on our data, together with that on the 3-half genomic sequence of the quail fast muscle TnT gene, we conclude that the avian fast skeletal muscle TnT gene includes 27 exons, 16 of which are alternatively spliced. 相似文献
22.
Koshiro Sugita Satoshi Ibara Toshio Harumatsu Chie Ishihara Yoshiki Naito Masakazu Murakami Seiro Machigashira Hiroyuki Noguchi Mitsuru Muto Makoto Matsukubo Satoshi Ieiri 《Journal of pediatric surgery》2021,56(7):1121-1126
Purpose: We aimed to investigate potential predictors of focal intestinal perforation (FIP) in extremely low birth weight infants (ELBWIs) among coagulation and fibrinolysis markers at birth.Methods: We reviewed the medical records of FIP patients and their coagulation and fibrinolysis markers at birth between 2010 and 2019, and matched patients according to gestational age. FIP was diagnosed based on macroscopic intestinal perforation with a punched-out lesion without necrosis. Patient characteristics and blood test results, including coagulation and fibrinolysis marker levels, were compared between the groups.Results: Two hundred forty ELBWIs were enrolled in this study (FIP, n = 18; controls, n = 222). In the FIP group, the gestational age at birth was significantly younger (p = 0.023) and the birth weight was significantly lower (p = 0.007) in comparison to the control group. Furthermore, the FIP group showed significantly lower levels of fibrinogen (p = 0.027) and factor XIII (F-XIII) (p = 0.007). The receiver operating characteristics curves for fibrinogen and F-XIII revealed that the 95% confidence intervals of fibrinogen and F-XIII were 0.530–0.783 (p = 0.027), and 0.574–0.822 (p = 0.007), respectively.Conclusions: This is the first report focusing on coagulation and fibrinolysis markers in FIP patients at birth. The fibrinogen and F-XIII values at birth are potential predictors of FIP in ELBWIs.Type of Study: Study of Diagnostic Test (Case Control Study)Level of Evidence: Level IV 相似文献
23.
Kiyoshi Koizumi Kunihiko Yokoyama Naoto Watanabe Suzuka Kawabata Noriyuki Shuke Seigo Kinuya Tamio Aburano Norihisa Tonami Kinichi Hisada Nobuo Sato Yoriaki Kurata 《Annals of nuclear medicine》1988,2(1):21-25
We developed monoclonal antibodies against human thyroid cancer-associated antigen by fusing mouse myeloma cells with mouse spleen cells immunized by insoluble fraction of homogenized thyroid papillary carcinoma cells. One monoclonal antibody (KTC-3, IgM) was selected to evaluate basic usefulness for radioimmunoscintigraphy in xenografted human thyroid carcinoma. KTC-3 was labeled with 131I by Iodogen method of 20 to 1 Iodogen to IgM molar ratio. It was also labeled with 111In by cyclic DTPA anhydride method of 20 to 1 DTPA to IgM molar ratio. The labeling efficiency and specific activity for 131I labeling were 16.5% and 0.66 mCi/mg IgM respectively, and those for 111In labeling were 12.7% and 1.6 mCi/mg IgM. Imaging and biodistribution of labeled KTC-3 were evaluated in nude mice bearing thyroid anaplastic carcinoma (THC-5-JCK). The tumors were well visualized 3 and 5 days after injection of 131I KTC-3. Tumor uptake of 131I KTC-3 on day 7 was 0.52 +/- 0.27% ID/g and tumor to blood ratio was 1.98 +/- 0.76 (n = 6). Those of 111In KTC-3 were 0.88 +/- 0.09% ID/g and 5.51 +/- 3.36 (n = 6). In conclusion, KTC-3 is promising for radioimmunoscintigraphy of thyroid cancer. 相似文献
24.
Belibi FA Reif G Wallace DP Yamaguchi T Olsen L Li H Helmkamp GM Grantham JJ 《Kidney international》2004,66(3):964-973
BACKGROUND: Progressive cyst enlargement, the hallmark of autosomal-dominant polycystic kidney disease (ADPKD) and autosomal-recessive (ARPKD) polycystic kidney disease, precedes the eventual decline of function in these conditions. The expansion of individual cysts in ADPKD is determined to a major extent by mural epithelial cell proliferation and transepithelial fluid secretion. This study determined if common receptor-mediated agonists and an anonymous lipid stimulate the production of 3' 5'-cyclic monophosphate (cAMP) in mural epithelial cells from the two major types of human cystic diseases. METHODS: cAMP responses to maximally effective concentrations of renal agonists were determined together with measurements of transepithelial anion current and cellular proliferation and extracellular signal-related kinase (ERK 1/2) expression in primary cultures of epithelial cells from human ADPKD and ARPKD cysts. RESULTS: The rank orders of responses to ligands for ADPKD and ARPKD cells were identical: epinephrine > desmopressin (DDAVP) approximately arginine vasopressin (AVP) > adenosine > prostaglandin E(2) (PGE(2)) > parathyroid hormone (PTH). cAMP concentrations elevated by epinephrine, DDAVP, adenosine, and PGE(2) were diminished by receptor-specific inhibitors. Pools of cyst fluid collected individually from 16 of 19 ADPKD kidneys increased, to varying degrees, cAMP levels in ADPKD and ARPKD cells. PGE(2), beta-adrenergic and AVP antagonists partially inhibited cAMP accumulation in response to fluids from three kidneys, but a large portion of the endogenous activity was attributed to yet-to-be identified bioactive lipid, designated cyst activating factor (CAF). CAF stimulated cAMP production in ADPKD and ARPKD cells, activated ERK(1/2), and increased cellular proliferation in ADPKD cells. CAF increased positive short circuit current (I(SC)) in polarized ADPKD and T-84 monolayers, indicating stimulation of net anion secretion. CONCLUSION: Endogenous adenylyl cyclase agonists promote cell proliferation and electrolyte secretion of human ADPKD and ARPKD cells in vitro. We suggest that increased levels of cAMP may accelerate cyst growth and overall renal enlargement in patients with PKD. 相似文献
25.
Ken-ichi Murase Tamio Takahei Hiroyuki Obata Kazuhiro Ohtsuka 《Journal of orthopaedic science》2002,7(1):48-55
We developed a new fixation device for reconstruction of the anterior cruciate ligament with a multistrand hamstring graft.
This device allows the graft tension to be readjusted after fixation. This device, called a Ligament Tension Screw, consists
of three parts, a screw, a washer, and a post. To create the graft, the tendons were formed into a loop. The device was hung
from one end of the loop of the graft and a Kennedy-ligament augmentation device (LAD) artificial ligament was hung at the
other end. The Kennedy-LAD artificial ligament was used extraarticularly for fixation at the tibia with double staples. Graft
tension was increased by turning the screw, which pulls on the post suspending the graft. Fifty-two patients were evaluated
after a minimum 2-year follow-up. The evaluation included physical examination, stability measurement with a KT2000 arthrometer,
a Cybex muscle strength measurement, a functional test, and scoring of the knee according to the International Knee Documentation
Committee (IKDC). Pivot test was negative in 47 patients (91%), but glide occurred in 5 patients (9%). No patient had a "clunk"
or markedly poor result on the pivot test. All patients recovered full extension. Seven patients lost full flexion, but the
loss of flexion was less than 5° in all seven. The KT 2000 arthrometer measurement with 133 N anterior drawer force indicated
that 46 patients (88%) had less than 3-mm side-to-side difference. The mean muscle strength of the quadriceps and hamstrings
was 91% and 94%, respectively, compared with the findings in the contralateral limb. The functional test showed a one-leg
hop distance equal to 94% of that the opposite side. According to the final IKDC evaluation, 48 patients were graded as normal
or nearly normal, and 4 patients as abnormal; none was severely abnormal. This study demonstrated satisfactory results for
the reconstruction with a multistrand hamstring graft fixed with the new Ligament Tension Screw.
Received: February 15, 2001 / Accepted: July 30, 2001 相似文献
26.
Tanycytic ependymomas are a subtype of ependymomas that were formally recognized as a new pathological entity in the latest World Health Organization (WHO) classification of 2000. They occur mostly in the spinal cord. Only a few reports have analyzed the proliferative potentials of these tumors; however, it has been reported that the MIB-1 labeling index of tanycytic ependymoma is lower than that of other subtypes of WHO grade II ependymomas. We report a rare case of cervicomedullary junction tanycytic ependymoma associated with marked cyst formation. A 62-year-old man had a history of progressive gait disturbance, diplopia, and swallowing disturbance over a one-month period prior to admission. Magnetic resonance imaging (MRI) showed a cystic mass with a mural nodule at the cervicomedullary junction with Gd-DTPA enhancement. Cyst-subarachnoid shunt was performed using a far lateral approach. After 6 years, however, the man was readmitted to the hospital because of reaccumulation of the cyst. Partial removal of a mural nodule and a cyst-subarachnoid shunt were performed simultaneously by a midline suboccipital approach. The pathological diagnosis was tanycytic ependymoma. Postoperatively, the patient recovered well and was discharged from the hospital without further treatment. Most of the tumor cells had small, round nuclei; pleomorphism was minimal. The cytoplasm was dilated. The tumor cells were positive for EMA and s-100, and negative for CD-34. GFAP was not determined due to difficulty caused by background glial processes. The MIB-1 labeling index was less than 1%. Ultrastructurally, the tumor cells had ependymal cell features, such as desmosomes and microvilli. Based on these findings, the pathological diagnosis was tanycytic ependymoma. 相似文献
27.
Background/Purpose
The introduction of laparoscope and transanal endorectal pull-through has caused a revolution in the operative procedures for Hirschsprung's disease. To study the changing profile of Hirschsprung's disease in Japan, the authors carried out a national survey.Method
Patient data were collected in 3 phases: group 1, 1628 patients between 1978 and 1982; group 2, 1121 patients between 1988 and 1992; and group 3, 1103 patients between 1998 and 2002, respectively.Results
The incidence was 1:4697, 1:5544, and 1:5343 and the male/female ratio was 3.0:1, 3.4:1, and 3.0:1 in each group, respectively. Patients weighing less than 2500 g at birth increased to 10.4% in group 3, whereas they were 6.5% in group 2 and 5.5% in group 1. The patients with a family history also increased to 6.0% in group 3, in comparison with 2.8% in group 2 and 3.0% in group 1. The incidence of associated anomalies increased over time, 11.1% in group 1, 16.3% in group 2, and 21.2% in group 3. Mutations of genes were found in 4 of the 23 patients examined. The extent of aganglionosis was almost the same in each group. Regarding the definitive operation, the procedures without laparotomy, including transanal endorectal pull-through, increased up to 42.6% in group 3 but 0% in groups 1 and 2. The frequency that a primary operation without stoma was performed also increased. The age at definitive operation decreased in group 3. The incidence of preoperative and postoperative enterocolitis also decreased over time. The mortality was decreased over time, 7.1%, 4.9%, and 3.0% for groups 1, 2, and 3, respectively.Conclusions
The authors analyzed 3852 Japanese patients over 3 decades. The ratio of patients with a low birth weight, associated anomalies, or a family history was increased in the last 10 years. A primary operation without laparotomy has thus become the procedure of choice for a definitive operation. 相似文献28.
29.
In this study, a questionnaire survey was carried out to determine the actual situation of radiation safety management systems in Japanese medical institutions with nuclear medicine facilities. The questionnaire consisted of questions concerning the Radiation Protection Supervisor license, safety management organizations, and problems related to education and training in safety management. Analysis was conducted according to region, type of establishment, and number of beds. The overall response rate was 60%, and no significant difference in response rate was found among regions. Medical institutions that performed nuclear medicine practices without a radiologist participating accounted for 10% of the total. Medical institutions where nurses gave patients intravenous injections of radiopharmaceuticals as part of the nuclear medicine practices accounted for 28% of the total. Of these medical institutions, 59% provided education and training in safety management for nurses. The rate of acquisition of Radiation Protection Supervisor licenses was approximately 70% for radiological technologists and approximately 20% for physicians (regional difference, p=0.02). The rate of medical institutions with safety management organizations was 71% of the total. Among the medical institutions (n=208) without safety management organizations, approximately 56% had 300 beds or fewer. In addition, it became clear that 35% of quasi-public organizations and 44% of private organizations did not provide education and training in safety management (p<0.001, according to establishment). 相似文献
30.
BACKGROUND/AIMS: We conducted a study on three-dimensional computed tomography (CT) images, in particular CT air-contrast enema (CT enema), using multidetector-row CT (MDCT), to see whether CT enema is useful as a preoperative examination for colorectal cancer. We aimed to evaluate the detectability of lesions and the depth of cancer invasion using CT enema. METHODS: 292 patients (328 lesions) with colorectal cancer were enrolled. After an adequate insufflation of the large intestine, MDCT scans were performed. With the data obtained by MDCT, we reconstructed CT enema images. CT enema images were assessed for the detectability of lesions. The depth of invasion was evaluated by the deformity of the lesion on profile images. The deformities were divided into five groups: no deformity, slight deformity, mild deformity, moderate deformity and severe deformity. RESULTS: The detectability of lesions was 97.3%. The reasons for undetectability were due to residual fluid in 8 cases and insufficient colonic distention in 1 case. As the depth of invasion increased, the grade of the deformity became severer (p < 0.0001). CONCLUSIONS: CT enema proved to be an excellent examination tool to detect lesions. The deformity demonstrated by CT enema could be an additional source of information to predict the depth of invasion. 相似文献