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1.
We report here the identification of the novel subunit of the mitochondrial F1F0-ATPase from Saccharomyces cerevisiae, ATPase subunit e. Yeast ATPase subunit e displays significant similarities in both amino acid sequence, properties (hydropathy and predicted coiled-coil structure) and orientation in the inner membrane, with previously identified mammalian ATPase subunit e proteins. Estimation of its native molecular mass and ability to be co-immunoprecipitated with a subunit of the F1-ATPase, demonstrate that subunit e is a subunit of the F1F0-ATPase. Stable expression of subunit e requires the presence of the mitochondrially encoded subunits of the F0-ATPase. Subunit e had been previously identified as Tim11 and was proposed to be involved in the process of sorting of proteins to the mitochondrial inner membrane. 相似文献
2.
Serum angiotensin converting enzyme activity (ACE), plasma renin activity (PRA), blood pressure (BP), blood pH, blood gases and lung function parameters were measured in patients with emphysema, extrinsic and intrinsic asthma, malignant pulmonary neoplasms, active sarcoidosis and healthy adults. Serum ACE activity was significantly higher in sarcoidosis (250.22+/-34.18 U/L); in small cell carcinoma of lung (155.10+/-38.25 U/L); emphysema (149.82+/-18.31 U/L); extrinsic asthma (141.22+/-25.30 U/L) and lower in intrinsic asthma (98.12+/-15.11 U/L) and squamous cell carcinoma of lung (97.294+/-18.85 U/L) when compared with that of control subjects (108.20+/-13.15 U/L). PRA and BP values of the patients with sarcoidosis, emphysema and small cell carcinoma were markedly elevated and sACE activity was found to be correlated with PRA and mean BP in the same diagnostic groups. sACE activity, PRA and BP of smokers were higher than those of non-smokers in control subjects and in patients with emphysema, extrinsic asthma and small cell carcinoma of lung. Oxygen tensions of the patients with emphysema , extrinsic asthma and small cell carcinoma of lung were found to be significantly decreased. Negative correlations between the sACE activity and oxygen tension (r= -0.68) and between the sACE activity and lung function parameters (r= -0.69 ) were found in these diagnostic groups suggesting that increased sACE level might appeared as a response to chronic hypoxia in the patients with emphysema, extrinsic asthma and small cell carcinoma of lung. 相似文献
3.
GS Pryhuber 《Canadian Metallurgical Quarterly》1998,64(4):217-228
BACKGROUND: The peptide antibiotic microcin B17 (MccB17) contains oxazole and thiazole heterocycles formed by the post-translational modification of four cysteine and four serine residues. An amino-terminal propeptide targets the 69 amino acid precursor of MccB17 (preproMccB17) to the heterocyclization enzyme MccB17 synthetase. The mode of synthetase recognition has been unclear, because there has been limited structural information available on the MccB17 propeptide to date. RESULTS: The solution structure of the MccB17 propeptide (McbA1-26), determined using nuclear magnetic resonance, reveals that McbA1-26 is an amphipathic alpha helix. Mutational analysis of 13 propeptide residues showed that Phe8 and Leu12 are essential residues for MccB17 synthetase recognition. A domain of the propeptide was putatively identified as the region that interacts with the synthetase. CONCLUSIONS: MccB17 synthetase recognizes key hydrophobic residues within a helical propeptide, allowing the selective heterocyclization of downstream cysteine and serine residues in preproMccB17. The determination of the solution structure of the propeptide should facilitate the investigation of other functions of the propeptide, including a potential role in antibiotic secretion. 相似文献
4.
Utilizing a paromamine-producing mutant of Micromonospora purpurea blocked in the production of gentamicin, bioconversion of various minor gentamicin components into the gentamicin C complex was demonstrated. The compounds tested were structurally related to the gentamicin C's and are found as minor components in the gentamicin fermentation. Based upon the bioconversions detected, a branched pathway for the biosynthesis of the gentamicin C components is proposed. 相似文献
5.
We study the fluctuations of native proteins by exact enumeration using the HP lattice model. The model fluctuations increase with temperature. We observe a low-temperature point, below which large fluctuations are frozen out. This prediction is consistent with the observation by Tilton et al. [R. F. Tilton, Jr., J. C. Dewan, and G. A. Petsko, Biochemistry 31, 2469 (1992)], that the thermal motions of ribonuclease A increase sharply above about 200 K. We also explore protein "flexibility" as defined by Debye-Waller-like factors and solvent accessibilities of core residues to hydrogen exchange. We find that proteins having greater stability tend to have fewer large fluctuations, and hence lower flexibilities. If flexibility is necessary for enzyme catalysis, this could explain why proteins from thermophilic organisms, which are exceptionally stable, may be catalytically inactive at normal temperatures. 相似文献
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7.
Local cerebral lesions may cause depression of function in remote areas of the brain presumably by a transneural mechanism; it has been called "diaschisis". In the present study, to investigate the relationship between motor function and "diaschisis" regional brain blood flow in hypertensive right putaminal hemorrhage was studied in 33 patients (mean age, 55 years; 22 men, 11 women). The hematoma was treated conservatively in 8 patients, aspirated stereotaxically in 9 patients, and evacuated through a craniotomy in 16 patients. The regional blood flow in the right motor cortex and the left cerebellar hemisphere was measured by a single photon emission CT with N-isopropyl-p- (123 I) iodo-amphetamine intravenous injection method, and was evaluated by the RI count on early image/the decay-corrected RI count on delayed image (E/D) value. The time during which regional brain blood flow was measured ranged from 29 to 35 days from the onset. There was a positive correlation between the grade in the motor function in the subacute stage and the regional blood flow in the right motor cortex and the left cerebellar hemisphere. There was also a positive correlation between the Barthel index in the chronic stage (mean follow-up periods: 40 months) and the regional blood flow in the right motor cortex and the left cerebellar hemisphere. The results of the present study suggest that in right putaminal hemorrhage the flow reduction in areas remote from the primary lesion, i.e., "diaschisis", may reflect not only the degree of functional abnormalities of the internal capsule, but also the possibility of functional recovery. 相似文献
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AIM: To study the mechanisms of the resistance to harringtonine (Har) in the HL60 cells. METHODS: Growth inhibition, karyotype analysis, flow cytometry, Western blotting and polymerase chain reaction. RESULTS: The Har-resistant HL60 cell line, named HR20, showed cross resistance to homoharringtonine, doxorubicin, daunorubicin, vincristine, and colchicine. The growth doubling time and the cell numbers in G1 phase were increased. The accumulation of cellular daunorubicin in the resistant cells was obviously reduced, but distinctly increased by tetrandrine and verapamil. The numbers of telocentromeric chromosome increased and the chromosomal aberration more occured in the resistant cells. The resistant cells overexpressed multidrug resistant mdr-1 gene and P-glycoprotein 150 kDa. CONCLUSION: The Har-resistant HL60 cell strain belonged to a multidrug resistance strain, overexpressing mdr-1 gene and P-glycoprotein. 相似文献
10.
K Takeda M Shibasaki N Imoto Y Shimakura H Takita 《Canadian Metallurgical Quarterly》1996,26(8):918-925
To understand the relevance of allergy to the development of asthma in children, we examined basophil histamine release (HR) with Df antigen, blood eosinophil counts, serum eosinophil cationic protein (ECP) levels, and bronchial responsiveness to methacholine (PC20) in three groups of children, including 36 asthmatics with high RAST titre for Df (group 1), 36 non-asthmatics with similarly high RAST titre for Df (group 2) and 21 non-asthmatics with negative RAST titre for Df (group 3). The amount of Df antigen inducing 50% HR from basophils did not vary significantly between group 1 and 2 (P > 0.05), while none of the cells responded to higher concentrations of Df in group 3. The mean number of blood eosinophils and level of serum ECP were highest in group 1, and lowest in group 3, with group 2 being intermediate, and the differences were significant between all three groups (P < 0.01). The mean PC20 value was the lowest in group 1, intermediate in group 2, and the highest in group 3, and the differences were significant between all three groups (P < 0.01). While correlation studies showed that PC20 values of group 2 subjects significantly correlated with their eosinophil numbers (r = -0.48, P < 0.01) and ECP levels (r = -0.49, P < 0.01), such correlations were not found in group 1 subjects. These results suggest that the degree of the eosinophilic inflammation caused by the allergic reaction to mites is an important factor in determining the clinical expression of asthma in atopic subjects. 相似文献
11.
DB McElhinney VM Reddy BG Feuerstein GR Marx FL Hanley 《Canadian Metallurgical Quarterly》1997,64(6):1827-1829
There have been 28 previously reported cases of neuroblastoma associated with congenital heart disease. Because many of these have been defects of the conotruncal region, it has been proposed that abnormal neural crest cell migration or maturation may be a factor that links these normally disparate pathologic conditions. Most neuroblastomas in these cases have been detected at autopsy or by radiologic studies conducted in the evaluation of the cardiac anomalies. Recently, we discovered an occult posterior mediastinal neuroblastoma in a patient undergoing a unifocalization procedure for tetralogy of Fallot with pulmonary atresia and major aortopulmonary collaterals. The tumor was resected, and the patient has demonstrated no evidence of residual or metastatic neuroblastoma. 相似文献
12.
S Guillemi JL Wright JC Hogg BR Wiggs PT Macklem PD Paré 《Canadian Metallurgical Quarterly》1995,8(5):789-794
The density dependence of maximal expiratory flow is not an effective test of the site of airway narrowing in obstructive lung disease. We hypothesized that the density dependence of pulmonary resistance (DD,RL) would be more closely related to the degree of airway narrowing and peripheral airway pathology in smokers. We measured maximal expiratory flow at 50% vital capacity (V'max50) and lung resistance (RL) breathing air and 80% helium-20% oxygen, and calculated density dependence of V'max50 and RL in 40 patients who had moderate airflow obstruction and in 10 normal subjects. We compared the density dependence of RL and V'max50 with the degree of airway obstruction and bronchiolar pathology scores in 27 patients with resected lung specimens. There were no differences in DD of V'max50 or RL between normal subjects and patients, and no relationship between the degree of obstruction or the bronchiolar pathology score and the DD of these measurements. There were significant relationships between V'max50, RL and the bronchiolar pathology scores. In conclusion, lung resistance and maximal expiratory flow are related to the severity of peripheral airway pathology, but there is no relationship between the severity of obstruction or the severity of peripheral airway pathology and the density dependence of maximal expiratory flow or lung resistance. 相似文献
13.
S Diederich M Semik MG Lentschig F Winter HH Scheld N Roos G Bongartz 《Canadian Metallurgical Quarterly》1999,172(2):353-360
OBJECTIVE: Our aim was to assess the sensitivity of helical CT for revealing pulmonary nodules. Thoracotomy with palpation of the deflated lung, resection, and histologic examination of palpable nodules was used as the gold standard. SUBJECTS AND METHODS: Thirteen patients underwent helical CT (slice thickness, 5 mm; reconstruction intervals, 3 mm and 5 mm; interpreted by two independent observers). Subsequently, patients underwent unilateral (n = 6) or bilateral (n = 7) surgical exploration, and CT-surgical correlation of 20 lungs was performed. RESULTS: Ninety nodules were resected (61 were smaller than 6 mm; 13 were 6-10 mm; 11 were larger than 10 mm; in five nodules, the size was not recorded at surgery). Sixty-nine nodules were located in the pulmonary parenchyma and 21 in the visceral pleura. Of the 90 lesions, 43 (48%) were found on histology to represent metastases. For lesions detected by at least one observer, the sensitivity of helical CT was 69% for intrapulmonary nodules smaller than 6 mm, 95% for intrapulmonary nodules larger than or equal to 6 mm, and 100% for histologically proven intrapulmonary metastases larger than or equal to 6 mm. For lesions smaller than or equal to 10 mm, sensitivity was better using a reconstruction interval of 3 mm rather than of 5 mm. CONCLUSION: In this study, the sensitivity of helical CT exceeded the sensitivity of conventional CT in previous reports. However, because of limitations in the detection of intrapulmonary nodules smaller than 6 mm and of pleural lesions, complete surgical exploration should remain the procedure of choice in patients undergoing pulmonary metastasectomy. Preoperative helical CT should be used to guide the surgeon to lesions that are difficult to palpate. 相似文献
14.
H Hamada M Sakatani S Yamamoto M Nishioka M Akira S Yamamoto E Ueda 《Canadian Metallurgical Quarterly》1998,36(10):864-870
We investigated the significance of eosinophilic cationic protein (ECP) as a biological indicator of disease activity in patients with eosinophilic pneumonia (EP). ECP levels were measured in serum and bronchoalveolar lavage fluid (BALF) samples from patients with EP or other diffuse interstitial lung diseases and from healthy subjects. Also we performed immunohistochemical staining of lung tissue sections from patients with EP using anti-EG 2 antibody, and computed the correlation between the number of EG 2-positive cells in lung tissues and ECP levels in serum and BALF from patients with EP. Levels of ECP in serum and BALF samples from patients with EP were significantly elevated compared to the levels in samples from other interstitial lung-disease patients and healthy subjects. Additionally, changes in serum ECP levels reflected the clinical courses for EP patients. Approximately 90 percent of the infiltrated eosinophils in tissue sections from patients with EP were EG 2-positive and activated. The number of EG 2-positive cells in lung tissues correlated significantly with levels of ECP in serum and BALF samples from patients with EP. These findings suggested that ECP levels in serum and BALF reflect the degree of eosinophil activation in lung tissues and the degree of disease activity in patients with EP. We concluded that ECP may serve as a useful biological indicator in EP. 相似文献
15.
Insect molting and metamorphosis are orchestrated by ecdysteroids with juvenile hormone (JH) preventing the actions of ecdysteroids necessary for metamorphosis. During the molt and metamorphosis of the dorsal abdominal epidermis of the tobacco hornworm, Manduca sexta, the isoforms involved in the ecdysone receptor (EcR)/Ultraspiracle (USP) complex change with the most dramatic switch being the loss of USP-1 and the appearance of USP-2 during the larval and pupal molts. We show here that this switch in USP isoforms is mediated by high 20-hydroxyecdysone (20E) and that the presence of JH is necessary for the down-regulation of USP-1 mRNA. The decrease of USP-1 mRNA in day 2 fourth instar larval epidermis in vitro required exposure to a high concentration (10(-5) M) of 20E equivalent to the peak ecdysteroid concentration in vivo, whereas the increase of USP-2 mRNA occurred at lower concentrations (effective concentrations, EC50=6.3x10(-7) M). During the pupal molt of allatectomized larvae which lack JH, USP-2 mRNA increased normally with the increasing ecdysteroid titer, whereas USP-1 mRNA remained high until pupation. When day 2 fifth instar larval epidermis was exposed to 500 ng/ml 20E in the absence of JH to cause pupal commitment of the cells by 24 h, USP-1 RNA remained at its high preculture level for 12 h, then increased two- to threefold by 24 h. The increase was prevented by the presence of 1 microgram/ml JH I which also prevents the pupal commitment of the cells. By contrast, USP-2 mRNA increased steadily with the same EC50 as in fourth stage epidermis, irrespective of the presence or absence of JH. Under the same conditions, mRNAs for both EcR-B1 and EcR-A isoforms were up-regulated by 20E, each in its own time-dependent manner, similar to that seen in vivo. These initial mRNA increases were unaffected by the presence of JH I, but those seen after 12 h exposure to 20E were prevented by JH, indicating a difference in response between larvally and pupally committed cells. The presence of JH which maintained larval commitment of the cells also prolonged the half-life of the EcR proteins in these cells. These results indicate that both EcR and USP RNAs are regulated by 20E and can be modulated by JH in a complex manner with only that of USP-2 apparently unaffected. 相似文献
16.
RK Scheule JA St George RG Bagley J Marshall JM Kaplan GY Akita KX Wang ER Lee DJ Harris C Jiang NS Yew AE Smith SH Cheng 《Canadian Metallurgical Quarterly》1997,8(6):689-707
Studies have indicated that although abundant levels of transgene expression could be achieved in the lungs of mice instilled with cationic lipid:pDNA complexes, the efficiency of gene transfer is low. As a consequence, a relatively large amount of the complex will need to be administered to the human lungs to achieve therapeutic efficacy for indications such as cystic fibrosis. Because all cationic lipids exhibit some level of cytotoxicity in vitro, we assessed the safety profile of one such cationic lipid, GL-67, following administration into the lungs of BALB/c mice. Dose-dependent pulmonary inflammation was observed that was characterized by infiltrates of neutrophils, and, to a lesser extent, macrophages and lymphocytes. The lesions in the lung were multifocal in nature and were manifested primarily at the junction of the terminal bronchioles and alveolar ducts. The degree of inflammation abated with time and there were no apparent permanent fibrotic lesions, even in animals that were treated at the highest doses. Analysis of the individual components of the complex revealed that the pulmonary inflammation was primarily cationic lipid-mediated with a minor contribution from the neutral co-lipid DOPE. Associated with the lesions in the lungs were elevated levels of the pro-inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) that peaked at days 1-2 post-instillation but resolved to normal limits by day 14. Total cell counts, primarily of neutrophils, were also significantly elevated in the bronchoalveolar lavage fluids of GL-67:pDNA-treated mice between days 1 and 3 but returned to normal limits by day 14. No specific immune responses were detected against the cationic lipid or plasmid DNA in mice that had been either instilled or immunized with the individual components or complex, nor was there any evidence of complement activation. These studies indicate that a significant improvement in the potency of cationic lipid:pDNA formulations is desirable to minimize the toxicity associated with cationic lipids. 相似文献
17.
J de la Cruz Alvarez J Montes Santiago T Cerda Mota C Fernández Pe?a C Fernández Marcos 《Canadian Metallurgical Quarterly》1997,14(12):611-614
STUDY OBJECTIVE: To assess adrenal function in patients with acute pleuropulmonary tuberculosis (APT) and compare it with that function in patients with community-acquired pneumonia (CAP). PATIENTS: Over a period of 6 months all consecutive patients 18 years of age or older with newly diagnosed APT and CAP were entered into the study. MEASUREMENTS: The whole patients had the following investigations: 1) Serum Na+, K+ and glucose concentrations 2) Systolic and diastolic blood pressures. 3) An ultrasonographic study of the adrenal glands. 4) A standard ACTH stimulation test. RESULTS: There was no significative difference in the serum cortisol level between the two groups at any time of the ACTH stimulation test (basal, 30 and 60 minutes), neither when taking into account the increments between basal and 60 minutes after stimulation serum cortisol levels. All patients in both groups had normal ACTH stimulation test with a peak stimulated cortisol level at 60 minutes > 504 nmol/L. CONCLUSIONS: We did not find evidence of adrenal cortical dysfunction in patients with acute pleuropulmonary tuberculosis or with community-acquired pneumonia in our hospital. 相似文献
18.
E Mercuri J Atkinson O Braddick S Anker F Cowan M Rutherford J Pennock L Dubowitz 《Canadian Metallurgical Quarterly》1997,77(2):F111-F114
AIM: To examine the effects of early lesions in the visual pathway on visual function; and to identify early prognostic indicators of visual abnormalities. METHODS: The visual function of 37 infants with perinatal brain lesions on magnetic resonance imaging was assessed using behavioural and electrophysiological variables. RESULTS: Normal visual behaviour was observed in most infants with large bilateral occipital lesions, but all the infants with associated basal ganglia involvement had abnormal visual function. Visual abnormalities were also present in six infants with isolated basal ganglia lesions. CONCLUSIONS: These observations suggest that basal ganglia may have an integral role in human visual development and that their presence on neonatal MRI could be an early marker of abnormal visual function. 相似文献
19.
N Shijubo K Shigehara M Hirasawa M Inuzuka S Abe 《Canadian Metallurgical Quarterly》1994,106(5):1481-1486
We measured eosinophilic cationic protein (ECP) concentrations in the circulation and bronchoalveolar lavage (BAL) fluids from patients with chronic eosinophilic pneumonia, patients with eosinophilic granuloma, and normal control subjects. Significantly increased ECP concentrations were found in the circulation of patients with chronic eosinophilic pneumonia and with eosinophilic granuloma compared with those found in control subjects. The ECP concentrations were well correlated to eosinophil counts in the circulation of patients with chronic eosinophilic pneumonia, while they were not in patients with eosinophilic granuloma. Chronic eosinophilic pneumonia patients had prominently increased ECP concentrations in BAL fluids compared with those found in control subjects, while eosinophilic granuloma patients did not. Those concentrations in chronic eosinophilic pneumonia patients were well correlated to eosinophil counts in the BAL fluid. Corticosteroid therapy remarkably decreased circulating ECP concentrations in three patients with chronic eosinophilic pneumonia, but it had no significant effects in two patients with eosinophilic granuloma. Measurement of ECP concentrations seems to be useful to evaluate the disease activity of chronic eosinophilic pneumonia. 相似文献