Type IV collagenase (gelatinase) is a 70,000 dalton neutral metalloproteinase that specifically cleaves type IV collagen in addition to degrading denatured collagen (gelatin). It is secreted in a latent proenzyme form that is converted proteolytically in the extracellular space to a 62,000 dalton active enzyme. The primary structure, enzymatic properties as well as gene structure, demonstrate that type IV collagenase is closely related with the other well characterized metalloproteinases, interstitial collagenase and stromelysin. However, the structure of type IV collagenase differs from the others in that it is larger and contains three internal repeats that resemble the type II domains of fibronectin. Also, initial characterization of the promoter region of the gene indicates that its regulation differs from the other proteinase genes. Type IV collagenase is presumably required for the normal turnover of basement membranes. Augmented activity is linked with the invasive potential of tumor cells and the enzyme is believed to play a major role in the penetration of basement membranes by metastatic cells. Measurements of enzyme activity and mRNA levels as well as immunostaining of a variety of tumor cells and tissues suggest that assays for the enzyme may have value in the follow-up of malignant growth.
The comparative analysis of 133 S. typhi clinical strains isolated from patients and carriers in Dnepropetrovsk Province in 1978-1987 was carried out. As shown by this analysis, 10 Vi phage types were represented in the set of strains under study, phage types A and F1 being the most numerous ones. Phage type F1 occurred less frequently among the strains isolated from carriers. 31.1% of the strains were found to contain plasmids with different molecular weight ranging from 96 to 0.5 MD. The occurrence of plasmid-containing strains remained at the same level during the whole period under study. Low-molecular plasmids occurred more frequently in the strains isolated from carriers. The minimal suppressive concentrations of a number of antibiotics, such as penicillin, ampicillin, monomycin, chloramphenicol, tetracycline, rifampicin and streptomycin, were determined. 7% of the strains were resistant to penicillin, 9% to monomycin, 15%--to tetracycline and 2.6% to chloramphenicol. The correlation between penicillin and monomycin resistance of the strains and the presence of the plasmid with a molecular weight of 60 MD in these strains was established. All strains were shown to be highly variable in the degree of their virulence: from 10(2) to 10(8). The strains isolated from patients possessed greater virulence.
The object of this research is to study acoustic emissions (AE) in aqueous solutions of polyethylene glycols (PEGs) of molecular masses from 300 to 3000 during cooling at 100 degrees C/min and heating at 70 degrees C/min in the temperature range from 0 to -196 degrees C. The dependence of AE intensity on PEG concentration and molecular mass is analysed. The AE intensity correlated with the crystalline to amorphous phase ratio in the frozen system.
to compare data on pre- and in hospital treatment of non ST-elevation (NSTE) acute coronary syndromes (ACS) in Russian ACS registers RECORD (recruitment from 11.2007 to 02.2008) and RECORD-2 (from 04/2009 to 04.2011).
Four of 7 hospitals participating in RECORD-2 were invasive (57.1% vs. 55.6% in RECORD). In RECORD-2 10-30 consecutive patients with NSTEACS were included monthly in each center; recruitment in RECORD was described elsewhere.
Mean age of patients was similar in two registries. Portion of women was significantly higher in RECORD-2 (42.9% vs. 26.0% in RECORD; 140) gave results close to those in all patients except mortality which was statistically similar but numerically higher in RECORD-2 (9.3 vs. 7.9% in RECORD; p=0.68).
Comparison of data of 2 limited NSTEACS registers conducted with interval of about 2 years showed only modest shift towards fulfillment of contemporary recommendations which was not associated with increase in rates of PCI and improvement of outcomes especially in high risk patients.
Polar fishes are known to have serum proteins and glycoproteins that protect them from freezing, by a noncolligative process. Measurements of antifreeze concentrations in ice and scanning electron micrographs of freeze-dried antifreeze solutions indicate that the antifreezes are incorporated in ice during freezing. The antifreezes also have a pronounced effect on the crystal habit of ice grown in their presence. Each of four antifreezes investigated caused ice to grow in long needles whose axes were parallel to the ice c axis. Together these results indicate the antifreezes adsorb to ice surfaces and inhibit their growth. A model in which adsorbed antifreezes raise the curvature of growth steps on the ice surface is proposed to account for the observed depression of the temperature at which freezing occurs and agrees well with experimental observations. The model is similar to one previously proposed for other cases of crystal growth inhibition.
Airway inflammatory responses to specific inhalation challenges (SICs) with low-molecular-weight (LMW) and high-molecular-weight (HMW) agents have not been studied thoroughly. We assessed the changes in airway inflammatory cells following SIC in sensitized workers, and looked at the influence of various factors on the pattern of inflammatory responses to SIC.
Induced sputum analysis was performed in workers sensitized to LMW (n = 41) or HMW agents (n = 41) after a control day and after a positive SIC. Cell counts were compared with lung function and various clinical parameters.
In the LMW group, eosinophils were increased following late asthmatic responses (median [interquartile range], 0.02 [0.04] × 10(6) cells/g vs 0.30 [0.80] × 10(6) cells/g and 1.0% [3.5] vs 8.9% [8.0], P
BACKGROUND: In general, the non-pyroglyphid mites Lepidoglyphus destructor and Blomia tropicalis show a different geographical distribution. Allergic sensitization to both species have been demonstrated in several investigations. However, whether this reflects cross-reactivity or dual sensitization is so far not known. OBJECTIVE: The aim of the study was to investigate the allergenicity and allergenic crossreactivity of L. destructor and B. tropicalis using sera from Sweden and Brazil. METHODS: Allergens in extracts of L. destructor and B. tropicalis were identified with SDS-PAGE and immunoblotting and the crossreactivity was studied by an immunoblot inhibition method. In addition to mite extracts, a recombinant major allergen of L. destructor, Lep d 2, was used. RESULTS: The extract prepared from L. destructor contained 21 IgE-binding components when using the Swedish or the Brazilian sera. A 15 kDa allergen was recognized by 85% of the Swedish sera and 78% of the Brazilian. The B. tropicalis extract exposed 23 IgE-binding components when the Brazilian sera were used and 19 when the Swedish sera were used. A total of 83% of the Brazilian sera and 80% of the Swedish sera identified a 14.5 kDa allergen. The IgE response of the Swedish serum pool to 10 B. tropicalis allergens was inhibited by L. destructor extract. Likewise, the response of the Brazilian serum pool to four different L. destructor allergens was inhibited by B. tropicalis extract. The recombinant Lep d 2 allergen inhibited 33% of the IgE binding of the Swedish serum pool to the 14.5 kDa allergen in the B. tropicalis extract. CONCLUSION: Crossreactivity with several proteins from L. destructor and B. tropicalis was demonstrated. The results suggest that a B. tropicalis 14.5 kDa allergen is antigenically crossreactive with recombinant L. destructor allergen Lep d 2.
alpha-Neoendorphin-like immunoreactivities (alpha-NE-IR) were demonstrated in tissues from three patients with medullary carcinoma of the thyroid (MCT). A large amount of alpha-NE-IR was detected in the extracts of primary tumors and metastatic lymphatic tissues by a highly sensitive and specific radioimmunoassay (RIA). Gel filtration analyses showed two different molecular-weight forms of the alpha-NE-IR: One eluted at the void fraction and the other at the position of [125I]-alpha-NE on Sephadex (Pharmacia Fine Chemical, Uppsala, Sweden) G-50 chromatography. Immunohistochemical examination revealed the presence of alpha-NE-IR in the C-cell carcinoma. These data presumably reflect that alpha-NE, the opioid peptide derived from preproenkephalin B, is synthesized in the MCT.
To characterize prostate-specific antigen (PSA) produced by cancer cells, different isoforms of PSA secreted by the human prostate cancer cells, LNCaP, were purified. LNCaP-PSA production was induced by synthetic androgen, R1881. LNCaP-PSA was separated into four pools. The molecular mass of LNCaP-PSA isoforms in these pools was 34 kDa under reducing conditions and 29 kDa under nonreducing conditions on SDS/PAGE. pI of LNCaP-PSA isoforms varied from 6.8 to 8.2. Pool A had the highest specific activity, 37 nmol/(min x mg). All the pools formed stable complexes with alpha1-antichymotrypsin and alpha2-macroglobulin. The pools contained 10-60% of N-terminally correctly processed LNCaP-PSA isoforms. According to the molecular modelling, the addition or deletion of two or four N-terminal amino acids could affect the three-dimensional structure and thereby remarkably reduce the enzyme activity of LNCaP-PSA.