III. Serum and sputum immunoglobulin E levels in respiratory diseases in adults

Using a solid-phase radioimmunoassay, serum IgE level was determined in 46 normal subjects, 53 patients with bronchial asthma, 44 patients with chronic bronchitis and / or emphysema, and 19 patients with restrictive lung disease. Sputum IgE was measured simultaneously in 51 of the subjects. The range of serum IgE concentration in the normal subjects was wide. It varied between 15 and 750 ng/ml with a mean of 135 ng. Asthmatic patients had significantly higher levels of serum IgE with a mean of 579 ng/ml, but only 30% fell outside the normal 95% confidence limits. Patients with chronic bronchitis, emphysema and restrictive lung diseases had normal IgE levels. There was a significant correlation between serum and sputum IgE levels.     

Ligand requirements for Ca2+ binding to EGF-like domains.

Site-specific mutagenesis studies of the first epidermal growth factor-like (EGF-like) domain of human clotting factor IX suggest that the calcium-binding site present in this domain (dissociation constant Kd = 1.8 mM at pH 7.5 and ionic strength I = 0.15) involved the carboxylate residues Asp47, Asp49 and Asp64. To further characterize the ligands required for calcium binding to EGF-like domains, two new mutations, Asp47----Asn and Asp49----Asn, were introduced into the domain by peptide synthesis. 1H-NMR spectroscopy was used to obtain the dissociation constants for calcium binding to these mutations. Calcium binding to the Asp49----Asn modified domain is only mildly affected (Kd = 6 mM, I = 0.15), whereas binding to the Asp47----Asn modified domain is severely reduced (Kd = 42 mM, I = 0.15). From these data, it is proposed that the anionic oxygen atoms of the side chains of residues 47 and 64 are essential for calcium binding, whereas the side chain ligand for calcium at residue 49 can be a carboxyamide oxygen. As a control, the introduction of the modification Glu78----Asp in a region of the domain not believed to be involved in calcium binding had very little effect on the Kd for calcium (Kd = 2.6 mM, I = 0.15). Finally, the effect of an Asp47----Gly substitution found in the natural haemophilia B mutant, factor IXAlabama, was investigated. This peptide has a markedly reduced affinity for calcium (Kd = 37 mM, I = 0.15), suggesting that the defect in factor IXAlabama is due to impaired calcium binding to its first EGF-like domain.     

Microbial colonization and succession in the large intestine of newborn infants during their stay with mothers at the maternity hospital]

Formation of microflora in the large intestine of 5-day old infants was studied in one of the Moscow maternity homes. The up-to-date procedures for isolation and identification of aerobic and anaerobic organisms were used in the study and the findings were processed on a computer. In the newborns of the maternity home of the "mother-infant" type there was observed colonization of the large intestine with aerobic and anaerobic organisms. A wave-like dynamics in the formation of the symbiotic microflora was revealed. It reflected the phenomenon of the microbial succession in the infants. The attempts to detect microbial interference between the species colonizing the large intestine showed that it was extremely rare in the 5-day old infants. This was likely the reason of the low intestine resistance to the colonization in the newborns which in its turn defined the frequent colonization of the intestine mucosa with S. aureus and the organisms of the Klebsiella, Enterobacter and Citrobacter group.     

Microbial colonization and succession on the faucial mucosa in newborn infants rooming in with their mothers in a maternity hospital]

The formation of microflora on the laryngeal mucosa in newborn infants during the first 5 days of their life was studied in one of the maternity hospitals of Moscow. In this work modern methods of the isolation and identification of aerobic and anaerobic microorganisms were used, and the results thus obtained were computer-processed. In the maternity hospital of the "mother-child" type the microbial colonization of the laryngeal mucosa by normal and opportunistic microorganisms was noted in newborn infants. A wave-like course of the formation of laryngeal microflora, indicative of microbial succession occurring in the child, was revealed. The attempt to establish the cases of microbial interference between the species colonizing the laryngeal mucosa revealed that it was very rarely observed in 5-day-old newborns. This feature was seemingly the cause of low resistance of the larynx to colonization in newborn infants, which determined frequent colonization of their laryngeal mucosa with Staphylococcus aureus and Klebsiella.     

Effect of microorganisms on rate of liquid extraction of ethanol from fermentation broths

Liquid extraction is one means of removing metabolic products continuously during a fermentation and so reducing product inhibition. It is known that microbial organisms are attracted to liquid-liquid interfaces, and it is important for the design of extraction systems to establish if this has a detrimental effect on the rate of extraction. The extraction of ethanol from aqueous suspensions of yeast (Saccharomyces cerevisiae) using n- decanol is described in this paper. It was found that the presence of the yeast cells severely reduced the rate of ethanol extraction. The overall mass transfer coefficient was reduced from 5.0 x 10(-6) to 0.7 x 10(-6) m/s. This reduced overall mass transfer coefficient was unaffected by yeast concentration in the range 0.1-20 kg/m(3). The results are consistent with the yeast cells adsorbing to the interface in closely packed layers and preventing mass transfer by simply reducing the available interfacial area. Optical microscope observations confirmed that a yeast layer several cell diameters thick rapidly built up at the interface when a small decanol droplet was added to a yeast suspension.     

A glycophospholipid covalently attached to the C-terminus of the Thy-1 glycoprotein

The Thy-1 glycoprotein is a very abundant cell surface molecule of rat thymocytes and neuronal cells with the properties of a molecule that inserts into the lipid bilayer. The hydrophobicity is due to a glycophospholipid component covalently attached to the carboxy group of the C-terminal cysteine residue. The mature glycoprotein does not contain a stretch of hydrophobic amino acids that could traverse the membrane bilayer. These findings present a new mode of membrane attachment for a cell surface molecule that can mediate lymphokine release and cell division after cross-linking by antibodies.     

Electron microscopic detection of calcium ions at different stages of normal surfactant formation and during body cooling

Histochemical demonstration of calcium ions in the respiratory part of the rabbit lungs has revealed that the greatest amount of the reaction granules is localized in type II alveolocytes. "Calcium packs" have been discovered, on the basis of which osmiophilic laminar bodies are formed. Cooling of the body entails an increase in the number of osmiophilic laminar bodies with calcium oxalate granules in type II alveolocytes.     

Meteorological factors and the time of onset of chest pain in acute myocardial infarction

Analysis of the time of onset of chest pain in 2254 patients with a myocardial infarction admitted to a coronary care unit in Leicester during a 10-year period shows an association with temperature and humidity. During both the most cold and humid times of the year, the relationship is a strong one. A generalized linear model with a log link was used to fit the data and the backward elimination selection procedure suggested a humid, cold day might help to trigger the occurrence of myocardial infarction. In addition, cold weather was found to have a stronger effect on the male population while those men aged between 50 and 70 years were more sensitive to the effect of high humidity.     

Secretion of recombinant proteins from hydroxyethyl methacrylate-methyl methacrylate capsules

Current human gene therapy relies on genetic modification of the patient's own cells. An alternate nonautologous approach is to use universal cell lines engineered to secrete therapeutic products. Protection with immunoisolation devices before implantation would allow the use of the same recombinant cell line for treating different patients, thus potentially lowering the cost of treatment. To study the properties of a mechanically stable synthetic biomaterial, hydroxyethyl methyacrylate-methyl methacrylate (HEMA-MMA) as the immuno-isolation device, we encapsulated recombinant mouse fibroblast cells engineered to secrete products ranging from 27 to 300 kDa in size (human growth hormone, mouse beta-hexosaminidase and beta-glucuronidase) in the presence or absence of the extracellular matrix Matrigel. Both viability and cell number in the microcapsules increased with time after encapsulation and cell morphology indicated viable cell growth, thus showing that the capsule membrane barrier was compatible with nutrient/waste exchange necessary for normal metabolic activity.The intracellular levels of these recombinant gene products were constant throughout the experimental period of 22 days in the presence or absence of Matrigel, thus demonstrating that the microenvironment did not lead to downregulation of the transgenes. However, the extracellular levels of the gene products secreted from the cells and trapped within the microcapsules were dependent on the molecular size of the product and presence of Matrigel. With the 27-kDa human growth hormone, the presence of Matrigel caused its retention within this intracapsular space, but its release from the microcapsules to the culture medium was not impeded. With the 120-kDa beta-hexosaminidase or the 300-kDa beta-glucuronidase, they were retained within the microcapsule space regardless of the presence or absence of Matrigel, and their passage from the microcapsules to the media was totally blocked. In conclusion, the HEMA-MMA microcapsules are supportive of recombinant cell growth and maintained their molecular cutoff at approximately 100 kDa. Inclusion of extracellular matrix was unable to improve cell growth and may impede the exit of some gene products. (c) 1996 John Wiley & Sons, Inc.