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81.
82.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
83.
We evaluated the intravenous infusion of a cocktail of I-131 anti-CEA and anti-C A19-9 monoclonal antibody F(ab’)2 (IMACIS-1) in patients with gastrointestinal neoplasm and liver metastases in order to assess its efficacy in detecting the presence of cancer. Seven patients with primary or recurrent gastrointestinal cancer in whom liver metastases were also detected were studied. Accumulation of radioactivity in the primary tumor was seen in only one patient. Visualization of the liver metastases was achieved in all patients. Thus detection of liver metastasis was better than in primary or recurrent tumors. While tumor visualization was most often seen in the 3 day image, optimal visualization of the tumor was seen at 5–7 days. There was no correlation between the serum concentration of CEA or CA19-9 and the visualization of tumors. Serum kinetics of I-131IMACIS-1 showed biexponential components with a 1st phase T1/2 of 5.0 hours and 2nd phase T1/2 of 34.7 hours. The mean whole body (I-131) half-life determined from the whole-body scans was 1.95 days. The mean urinary excretion of I-131 in 7 days was 85%. This value agreed closely with total radioactivity retention detected by scanning. This series of studies demonstrated the potential utility of a cocktail of antibodies consisting of an anti-CEA and an anti-CA19-9 monoclonal F(ab’)2.  相似文献   
84.
We have developed a simple method to correct the washout of tracer from the brain based on the two-compartment model in brain early SPECT using N-isopropyl-p-[123I]iodoamphetamine (123I-IMP). This correction was applied to a new quantitative method of regional cerebral blood flow (rCBF) in combination with the microsphere method by continuous arterial sampling previously reported. Data acquisition of 123I-IMP early SPECT was started from 35 min after 123I-IMP i.v. injection, and the time activity curve of whole brain on anterior head planar images was monitored immediately after 123I-IMP i.v. injection for the correction of washout of tracer from the brain. The usefulness of this method was evaluated in 12 patients with various brain diseases by comparison with the results obtained from the super-early SPECT at 7-10 min after 123I-IMP i.v. injection. The washout rates in cases of early SPECT corrected by this method ranged from 16.91% to 39.34% with a mean +/- SD of 27.72 +/- 5.44%. The contrast of hypo- to hyperperfusion regions on early SPECT was improved by the correction of the washout, and its intracerebral distribution was similar to the simultaneously obtained super-early SPECT images. These results indicated that the present correction method for the washout was useful for more correct quantification of rCBF.  相似文献   
85.
As both tissue inhibitor of metalloproteinases-1 (TIMP-1) and TIMP-2 have been reported to inhibit bone resorption, we examined whether TIMP-1 or TIMP-2 in fetal calf serum (FCS), with which culture media were supplemented, affected osteoclastic bone resorption in vitro. Contrary to our expectation, almost complete suppression of osteoclastic bone resorption was observed when both TIMP-1 and TIMP-2 were removed from the FCS. Bone resorption was, however, almost fully restored by the addition of recombinant TIMPs. TIMPs stimulate bone resorption at significantly lower concentrations (∼ng/ml) than those (∼μg/ml) required to inhibit bone resorption. To understand the mechanism of TIMP-dependent bone resorption, we counted and compared the number of tartrate-resistant acid phosphatase-(TRAP-) positive and multinuclear cells in cultures containing either 10% FCS or TIMP-1-free and/or TIMP-2-free FCS. There was essentially no difference in number among these, suggesting that the TIMP role seems to be related to the functional expression of osteoclasts. Metallo-proteinase inhibitors, either BE16627B[l-N-(N-hydroxy-2-isobutylsuccinynamoyl)-seryl-l-valine] or R94138 {N-methyl-(3S)-2-[(2R)-2-hydroxycarbamoylmethylundecanoyl] hexahydropyridazine-3-carboxamide}, could not replace TIMPs, suggesting that the osteoclast-stimulating activity of TIMPs cannot be ascribed to merely their inhibitory effect on matrix metalloproteinases. Received: Oct. 15, 1998 / Accepted: April 5, 1999  相似文献   
86.
A 67 year old Japanese male patient had pure agraphia after a haemorrhage in the left superior parietal lobule. He developed difficulty in letter formation but showed no linguistic errors, consistent with the criteria of apraxic agraphia. He manifested a selective disorder of sequencing writing strokes, although he was able to orally state the correct sequences. The patient's complete recovery after 1 month, without new learning, showed that he had manifested a selective disorder of writing stroke sequences. These findings indicate that the final stage of the execution of writing according to acquired sequential memory shown as a stroke sequence can be selectively disturbed, and should be considered to be distinct from the ability of character imagery and the knowledge of the writing stroke sequence itself. This case also indicates that the left superior parietal lobule plays an important part in the execution of writing.  相似文献   
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BACKGROUND: With the shortage of cadaveric donors, non-heart-beating donors (NHBDs) are a potential source of liver allografts. However, warm ischemic injury in NHBDs seriously affects the viability of graft liver. Endothelin (ET)-1 has been reported to be involved in the hepatic microcirculatory disturbances after ischemia-reperfusion. METHODS: In a porcine orthotopic liver transplantation model, changes in the serum and liver tissue ET-1 concentration were measured and the effects of an ET receptor antagonist, TAK-044, were evaluated. After cardiac arrest of the donors, liver allografts were subjected to 90 min of warm ischemia, flushed, and preserved for 4 hr at 4 degrees C. The pigs were divided into two groups: a control group (no drug treatment) and a drug-treated group, in which donors and recipients were treated with TAK-044 (10 mg/kg body, drip intravenous injection). Both groups had six donor/recipient pairs. RESULTS: -The ET-1 concentration in the hepatic venous blood increased after reperfusion of the graft in the control group recipients. ET-1 in the graft liver significantly increased during the cold preservation period. TAK-044 treatment significantly increased recipient 7-day survival rate. After reperfusion of the graft, the concentrations of serum liver enzymes and arterial lactate in the drug-treated group were significantly lower than in the control group. The postoperative increase in portal venous pressure was significantly reduced in the drug-treated group. Measurements of liver enzymes in the washed-out preservation fluid at the time of graft rinsing indicated that TAK-044 treatment of the donors significantly suppressed liver enzyme release during ischemia. CONCLUSIONS: These findings indicate TAK-044 treatment has protective effects on postoperative function of hepatic allografts procured from NHBDs.  相似文献   
90.
Metastable Equilibrium Solubility Behavior of Bone Mineral   总被引:1,自引:1,他引:0  
Previous studies have shown that carbonated apatites with a range of carbonate contents and crystallinities exhibit the phenomenon of metastable equilibrium solubility (MES) distributions. The purpose of the present study was to investigate the solubility behavior of bone mineral using the concepts of MES and MES distributions and, together with crystallinity and chemical composition data, examine the similarity of bone mineral to carbonated apatite (CAP). Bone samples were harvested from 1-, 5-, and 8-month-old rats. The organic components of the bone samples were removed by hydrazine deproteination. Carbonated apatite was synthesized by the hydrolysis of dicalcium phosphate dihydrate (DCPD) in a NaHCO3-containing media at 50°C. The MES distributions of bone mineral and CAP were determined by equilibrating predetermined amounts of CAP or bone mineral in a series of 0.1 M acetate buffers containing calculated levels of calcium and phosphate and maintained at essentially constant pHs of 5.0, 5.3, 5.7, and 6.5. From the compositions of the equilibrating buffer solutions, ion activity products based upon the stoichiometries of octacalcium phosphate, hydroxyapatite, and carbonated apatite were calculated in an attempt to determine the function governing the dissolution of CAP and bone mineral. The results of this study demonstrated that the MES distribution phenomenon appeared to hold for bone mineral and that the changes in crystallinity of bone mineral with age correlated well with changes in the MES values. A CAP sample was prepared that was found to be an excellent synthetic prototype closely mimicking the physicochemical behavior of bone mineral from an 8-month-old rat. Another finding of this study was that the ion activity product function based upon the hydroxyapatite stoichiometry well described the MES results obtained with both CAP and bone mineral. The interpretation that a surface complex with hydroxyapatite stoichiometry governs the solubility behavior of bone mineral is, therefore, consistent with the experimental data. Other calcium phosphate stoichiometries for the surface complex showed systematic variations in the MES profiles when the pH of the equilibrating solution was varied. Received: 30 October 1997 / Accepted: 1 October 1998  相似文献   
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