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21.
Polyglutamine (polyQ) diseases are a growing class of inherited neurodegenerative diseases including Huntington's disease, which are caused by abnormal expansions of the polyQ stretch in each unrelated disease protein. The expanded polyQ stretch is thought to confer toxic properties on the disease proteins through alteration of their conformation leading to pathogenic protein-protein interactions including oligomerization and/or aggregation. Hypothesizing that molecules with selective binding affinity to the expanded polyQ stretch may interfere with the pathogenic properties, we previously identified Polyglutamine Binding Peptide 1 (QBP1) from combinatorial peptide phage display libraries. We show here that a tandem repeat of the inhibitor peptide QBP1, (QBP1)(2), significantly suppresses polyQ aggregation and polyQ-induced neurodegeneration in the compound eye of Drosophila polyQ disease models, which express the expanded polyQ protein under the eye specific promoter. Most importantly, (QBP1)(2) expression dramatically rescues premature death of flies expressing the expanded polyQ protein in the nervous system, resulting in the dramatic increase of the median life span from 5.5 to 52 days. These results suggest that QBP1 can prevent polyQ-induced neurodegeneration in vivo. We propose that QBP1 prevents polyQ oligomerization and/or aggregation either by altering the toxic conformation of the expanded polyQ stretch, or by simply competing with the expanded polyQ stretches for binding to other expanded polyQ proteins. The peptide inhibitor QBP1 is a promising candidate with great potential as a therapeutic molecule against the currently untreatable polyQ diseases.  相似文献   
22.
The isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN) is a new isothermal DNA amplification method composed of exo Bca DNA polymerase, RNaseH and DNA-RNA chimeric primers. We developed the simultaneous detection system for Chlamydia trachomatis/Neisseria gonorrhoeae DNA, combined with luminescence detection by a probe hybridization. In the performance tests, this system was able to detect 10 to 100 copies of C. trachomatis/N. gonorrhoeae DNA for only 3.5 hours, and was highly specific to C. trachomatis/N. gonorrhoeae without any cross-reaction to C. pneumoniae, N. lactamica, N. sicca or N. meningitidis. When we tested 60 clinical samples of urine and cervical swabs, the interpretive results were completely consistent with those obtained by Roche PCR system. Of 13 positive samples by the ICAN and PCR systems for C. trachomatis, four were negative by EIA method(IDEIA Chlamydia). These results indicate that the ICAN system is an efficient and sensitive system to simultaneously detect C. trachomatis/N. gonorrhoeae DNA.  相似文献   
23.
In aperiodic rats with lesions in the suprachiasmatic nuclei (SCN), rhythms with a circadian period in spontaneous locomotion, wheel-running, feeding, drinking, body temperature and plasma corticosterone were restored by chronic administration of methamphetamine. These rhythms were not entrained by a light-dark cycle. Wheel-running, feeding and drinking rhythms in individual rats were in phase in terms of ultradian bout as well as circadian fluctuation. Rhythms of the intraperitoneal temperature appeared accompanying the spontaneous locomotor rhythm. The phase relation between the two rhythms was similar to that of SCN dependent rhythms. Plasma corticosterone also fluctuated in a circadian fashion. The corticosterone peak preceded the activity onset of locomotor rhythm by a few hours, which was similar to the phase relation observed in the SCN intact animals. It is concluded that the oscillatory mechanism underlying the spontaneous locomotor rhythm in SCN lesioned and methamphetamine treated rats drives also other physiological rhythms. The phase-relations among them were similar to those of rhythms driven by the circadian pacemaker in the SCN.  相似文献   
24.
The ACOSOG Z0011 trial has resulted in the omission of axillary lymph node dissection (ALND) in early breast cancer patients with one or two metastatic sentinel lymph nodes (SLNs). There has been increasing interest in the necessity of intraoperative assessment of SLNs in patients treated based on the Z0011 criteria. We evaluated the utility of intraoperative assessment in these eligible patients. A total of 1396 patients were treated following the Z0011 criteria from April 2012 to December 2019. We examined the proportion and clinicopathological features of patients who underwent ALND due to three or more metastatic SLNs and the sensitivity of intraoperative assessment. Only 16 (1.1%) patients had three or more metastatic SLNs diagnosed by intraoperative assessment, and they immediately underwent ALND. Of the clinicopathological factors, high clinical tumor stage (p = 0.002) and high Ki-67 labeling index value (p = 0.056) were more likely to be associated with the presence of three or more metastatic SLNs. The major independent risk factor for three or more metastatic SLNs was high clinical tumor stage (OR 3.94 [95% CI 1.42–11.0]; p = 0.009). Intraoperative assessment had low sensitivity (70.5%) and a high false-negative rate (29.5%) in detecting SLN metastases. The main finding of our study was the small proportion of patients who required ALND due to three or more metastatic SLNs according to the Z0011 criteria. The Z0011 strategy enables intraoperative assessment of SLNs to be omitted in early breast cancer patients.  相似文献   
25.
A 31-year-old woman was admitted to our center with left chest pain and dyspnea after treatment of pulmonary tuberculosis. Chest X-ray film showed atelectasis of left lower lobe and left deviation of the mediastium. Bronchofiberscopy revealed obstruction of the left main bronchus. Chest MRI showed intermediate intensity at the left main bronchus and very high intensity at the peripheral bronchus. We performed sleeve resection of the left main bronchus and anastomosed end to end with absorbable monofilament sutures. Postoperative course was uneventful. Bronchoplasty for tuberculous obstructive lesion is a useful procedure.  相似文献   
26.
27.
Osaterone acetate (17alpha-acetoxy-6-chloro-2-oxa-4,6-pregnadiene-3,20-dione, OA) is a new steroidal antiandrogen. There is a marked species difference in the metabolism of OA in that 11beta-hydroxylated metabolites are found in the plasma, feces, and urine of mice after oral administration of OA, but there is very little metabolism in rats and humans. OA reduces the adrenal gland weight in mice, but not in rats, and this effect in mice might be explained by the species difference in 11beta-hydroxylation activity. The objectives of this study were to elucidate the enzyme(s) involved in this particular oxidation and to explain the species difference observed. Mouse hepatic microsomes oxidize OA to 11beta-OH OA, and this oxidation requires NADPH as a cofactor. The use of various competitive and allosteric inhibitors of cytochrome P450 and flavin-containing monooxygenase (i.e. CO, N-octylamine, and methimazole) showed that the oxidation of OA was catalyzed by cytochrome P450. In microsomes from mice pretreated with phenobarbital (a CYP2B-selective inducer), 3-methylcholanthrene (a CYP1A-selective inducer), pregnenolone-16alpha-carbonitrile (a CYP3A-selective inducer), and EtOH (a CYP2E-selective inducer), an increase in the rates of oxidation was seen only in microsomes from EtOH-treated animals. However, metyrapone, a selective inhibitor for enzymes of the cytochrome P45011B and P4502B family, inhibited mouse hepatic microsomal 11beta-hydroxylation by < 30%. The results obtained showed that the production of 11beta-OH OA may be catalyzed by a novel cytochrome P450 in mouse liver.  相似文献   
28.
Summary Maximum motor nerve conduction velocities in the median nerve (MCV) and blood lead (PbB) were repeatedly measured in 14 lead exposed workers with an initial PbB from 0.7 to 4.0 mol/kg (median 2.3 mol/kg) for a period from 3 months to 7 years: A certain dose of Calcium Disodium Ethylenediaminetetraacetic Acid (CaEDTA) was injected intravenously into most of the subjects during the period.In seven subjects, MCV improved by more than 4 m/s during the observation period which involved the first two successive measurements of MCV and PbB, but the remaining seven subjects showed the minimal alteration (within ± 4.0 m/s). The initial value of MCV was significantly slower (P < 0.01) and the decrease in PbB was significantly greater (P < 0.05) in the group of subjects having shown the improvement of MCV by more than 4 m/s.The initial value of MCV was significant in determining the alteration in MCV in multiple regression analysis and, together with the change in PbB, explained 31% of the alteration in MCV between the first two successive measurements. The initial level of PbB, dose of CaEDTA, time interval between the measurements and age played no essential part in the alteration in MCV.The alteration in MCV throughout the whole observation period in each subject significantly correlated with the concurrent change in PbB (r=–0.573, P < 0.001).  相似文献   
29.
Two patients with postoperative interstitial pneumonia are reported. Preoperative diagnosis was primary lung cancer without idiopathic interstitial pneumonia (IIP). Within one week after operation acute interstitial pneumonia (AIP) occurred on the nonoperated side and developed. Steroid therapy was performed but one was dead. AIP is a fatal complication after pulmonary resection and steroid therapy may be useful in some cases of postoperative AIP.  相似文献   
30.
A case of congenital cystic adenomatoid malformation (CCAM) of the lung is reported. A 3-year-old boy was admitted for elevation of infiltrative shadow in the right lower lung field on a chest X-ray. The clinical diagnosis was emphysematous bullae with inflammation. After 6 months, he had recurrent infected bullae, and was admitted. He received chemotherapy with antibiotics prior to the operation. Right lower lobectomy was performed on February 2, 1998. The resected lung was composed of multiple cysts with thin wall measuring 10-60 mm in diameter. The histological examination of specimen revealed CCAM (Stocker type I), which is rare in this age. The patient has been well for 16 months postoperatively.  相似文献   
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