Two forms of complement-depleting cobra venom factor (CVFm1 and CVFm2), possessing molecular masses of 142.6 kDa (CVFm1) and 143.1 kDa (CVFm2), according to MALDI mass-spectrometry, were isolated from the Naja melanoleuca cobra venom. As shown by polyacrylamide gel electrophoresis in the presence of SDS, both forms similarly to factor from the Naja kaouthia cobra venom (CVFk) consist of three polypeptide chains with molecular masses of about 70, 50, and 30 kDa, the two large subunits being glycosylated. As determined by MALDI mass-spectrometry, 30 kDa subunits of CVFm1 and CVFm2 have considerably different finger-prints of tryptic digests that suggests differences in their amino acid sequences. A study of activity in vivo has shown no significant differences in C3 consumption by CVFm1, CVFm2 and CVFk in mouse blood. However, as shown by an immunoassay method, they differ in their ability to activate the complement system via C3 conversion, the ratio of these activities for CVFm1:CVFm2:CVFk being 2.5:1.6:1. Kinetic studies using a hemolytic test showed that complement depletion by CVFm1 is faster than that by CVFm2. Thus, for the first time the presence in a single venom of two forms of CVF differing by both amino acid sequence and biological activity has been shown. 相似文献
A transmission-type ionization chamber for monitoring dose power of the Roentgen-TA 150/10 X-ray therapeutic apparatus is described. The X-ray working dose range of the apparatus is 4.5-70 keV. The X-ray chamber sensitivity at Al equivalent 100 nm for X-ray energy 4.5 keV is 2·10–11 A/mGy/sec. Relative spectral sensitivity error of the chamber within the given range is ±13.0 %. The correction of the apparatus reduces this error to ±3.0 %. 相似文献
High-dose immunosuppressive therapy (HDIT) with autologous hematopoietic stem cell transplantation (auto-HSCT) is a new and promising approach to the treatment of multiple sclerosis (MS) patients because currently there are no effective treatment methods for this disease. In this article, we present results of a prospective clinical study of efficacy of HDIT + auto-HSCT in MS patients. The following treatment strategies were employed in the study: "early," "conventional," and "salvage/late" transplantation. Fifty patients with various types of MS were included in this study. No toxic deaths were reported among 50 MS patients; transplantation procedure was well-tolerated by the patients. The efficacy analysis was performed in 45 patients. Twenty-eight patients achieved an objective improvement of neurological symptoms, defined as at least 0.5-point decrease in the Expanded Disability Status Scale (EDSS) score as compared to the baseline and confirmed during 6 months, and 17 patients had disease stabilization (steady EDSS level as compared to the baseline and confirmed during 6 months). The progression-free survival at 6 years after HDIT + auto-HSCT was 72%. Magnetic resonance imaging data were available in 37 patients before transplantation showing disease activity in 43.3%. No active, new, or enlarging lesions were registered in patients without disease progression. In conclusion, HDIT + auto-HSCT suggests positive results in management of patients with different types of MS. Identification of treatment strategies based on the level of disability, namely "early," "conventional," and "salvage/late" transplantation, appears to be feasible to improve treatment outcomes. 相似文献
Magnetically driven torsional actuation of a multiwalled carbon nanotube (MWNT) yarn was realized by first biscrolling NdFeB magnetic particles into helical yarn corridors to make a magnetic MWNT yarn. The actuating device comprised a pristineMWNT yarn that was connected to the magnetic MWNT yarn, with a paddle attached between these yarns. The application of a magnetic field reversibly drove torsional actuation of up to 80° within ∼0.67 seconds. This magnetic actuator was remotely powered, and its actuation stroke was the same when the muscle array was at 20 °C and at −100 °C.Magnetically driven torsional actuation of a multiwalled carbon nanotube (MWNT) yarn was realized by first biscrolling NdFeB magnetic particles into helical yarn corridors to make a magnetic MWNT yarn. 相似文献
Bulletin of Experimental Biology and Medicine - Changes in the Shaganin lymphocyte index (ratio of the number of lymphocytes to segmented neutrophils) in the peripheral blood of rats after... 相似文献
A novel method for the investigation of the chain‐end structure of poly(1,3‐pentadiene)s synthesized using the CF3COOD/TiCl4 initiating system is developed. It is shown for the first time that the content of trans‐1,2‐structures in the first monomer unit is considerably higher than the content of trans‐1,4‐structures, whereas the content of trans‐1,4‐units is substantially higher than trans‐1,2‐units for the polymer chain as a whole. Another important observation is that chain transfer to monomer is significant even at the earlier stages of the 1,3‐pentadiene polymerization (after 1 s of reaction). The very low functionality at the ω‐end (Fn(Cl) < 0.15) confirms the intensive chain transfer to monomer. This method is also applied for the estimation of the concentration of active species and the rate constant for propagation (kp) for the cationic polymerization of 1,3‐pentadiene using the CF3COOD/TiCl4 initiating system: rate constants for propagation, kp, of 1.5 × 103 and 3.3 × 103 L mol?1 min?1 are determined for 1,3‐pentadiene polymerization at 20 and –78 °C, respectively.
Paroxysmal nocturnal haemoglobinuria (PNH) clones are frequently detected in patients with aplastic anaemia (AA). To evaluate the prognostic role of PNH clone presence we conducted a prospective study in 125 AA patients treated with combined immunosuppressive therapy (IST). Seventy‐four patients (59%) had a PNH clone (PNH+ patients) at diagnosis, with a median clone size of 0·60% in granulocytes and 0·15% in red blood cells. The response rate at 6 months was higher in PNH+ patients than that in PNH‐ patients, both after first‐ and second‐line IST: 68% vs. 45%, P =0·0164 and 53% vs. 13%, P =0·0502 respectively. Moreover, 42% of PNH+ patients achieved complete remission compared with only 16% of PNH‐ patients (P =0·0029). In multivariate logistic regression analysis, PNH clone presence (odds ratio 2·56, P =0·0180) and baseline absolute reticulocyte count (ARC) ≥30 × 109/l (odds ratio 5·19, P =0·0011) were independent predictors of response to treatment. Stratification according to PNH positivity and ARC ≥30 × 109/l showed significant distinctions for cumulative incidence of response, overall and failure‐free survival. The results of this prospective study confirmed the favourable prognostic value of PNH clone presence in the setting of IST for AA. 相似文献
The ear detects sounds so faint that they produce only atomic-scale displacements in the mechanoelectrical transducer, yet thermal noise causes fluctuations larger by an order of magnitude. Explaining how hearing can operate when the magnitude of the noise greatly exceeds that of the signal requires an understanding both of the transducer's micromechanics and of the associated noise. Using microrheology, we characterize the statistics of this noise; exploiting the fluctuation-dissipation theorem, we determine the associated micromechanics. The statistics reveal unusual Brownian motion in which the mean square displacement increases as a fractional power of time, indicating that the mechanisms governing energy dissipation are related to those of energy storage. This anomalous scaling contradicts the canonical model of mechanoelectrical transduction, but the results can be explained if the micromechanics incorporates viscoelasticity, a salient characteristic of biopolymers. We amend the canonical model and demonstrate several consequences of viscoelasticity for sensory coding. 相似文献