Isolation of lipid-free C-reactive protein by affinity chromatography

Human C-reactive protein purification has been hampered by its association with lipids. Isolation of pure lipid-free C-reactive protein was obtained by a three step procedure. First, partially lipid-free C-reactive protein was obtained by affinity chromatography from ascitic fluids; second, lipid-bound proteins were eliminated by calcium-dependent precipitation; and third, lipid-free pure C-reactive protein was obtained by affinity re-chromatography of the supernatant. A 46-50% yield of lipid-free C-reactive protein was obtained compared with the 14.7% obtained by the old method of extraction with lipid solvents.     

Trypanosoma rhodesiense: variant specificity of immunity induced by irradiated parasites.

Rats immunized with irradiated Trypanosoma rhodesiense resisted infection with the homologous strain. When similarly immunized rats were challenged with parasites obtained from rhesus monkeys infected with the same strain, resistance depended on when parasites were obtained from the donor monkeys. Immunized rats challenged with trypanosomes obtained from a monkey during the first peak of parasitemia were solidly immune; immunized rats challenged with trypanosomes obtained from monkeys after their initial peak of parasitemia all succumbed to the challenging infection. These observations indicate that parasites of a variant antigenic specificity arose during the course of the monkey infections. Neutralization tests performed on the various isolates from rats and monkeys using antiserum obtained from immunized rats confirmed that the immunity produced by irradiated trypanosomes was variant specific.     

Antimicrobial susceptibility tests for anaerobic bacteria. Comparison of Wilkins-Chalgren agar reference method and a microdilution method,and determination of stability of antimicrobics frozen in broth

Susceptibility results for anaerobic bacteria obtained with a microdilution method with either Wilkins-Chalgren broth or Brain Heart Infusion broth were compared to results obtained with the reference agar dilution method proposed by the National Committee for Clinical Laboratory Standards. Results were generally comparable, but the minimal inhibitory concentrations obtained with the microdilution method were slightly lower than those obtained with the agar dilution method. Antibiotics stored in these broths in microdilution trays at-20°C were stable for up to 130 days.     

Evaluation of purified H and M antigens of histoplasmin as reagents in the complement fixation test.

Complement-fixation (CF) tests were performed with purified H and M antigens, histoplasmin, and Histoplasma capsulatum whole cell yeast phase antigen using sera of 126 patients with proven or suspected histoplasmosis. Specific titers for either H or for M antibody were obtained with the individual purified antigens; the highest titers were comparable to those obtained with histoplasmin. However, in sera containing only anti-M antibody, the titers obtained with the purified M antigen were 2 to 16 times those obtained with the histoplasmin or yeast phase antigens. The CF test for either H or M antibody was 4 to 32 times as reactive as the agar-gel microimmunodiffusion test; in general precipitin lines were obtained with either H or M antigens from sera with CF titers greater than or equal to 8. With sera containing H antibody, there was an excellent correlation between the CF titers obtained with purified M antigen and histoplasmin. The correlations of CF titers with H antigen and either histoplasmin or yeast phase antigen were very low.     

Validation of estimated muscle fiber conduction velocity with the normalized peak-averaging technique.

To estimate muscle fiber conduction velocity (MFCV), the normalized peak-averaging technique was developed along with complementary software and reported in a previous study. Electromyograms were recorded from the vicinity of end-plate zones (EMG data 1) and a site farther from the end-plates and distal tendons (EMG data 2) of biceps brachii muscles using surface array electrodes during 50% maximal voluntary isometric contractions in ten healthy volunteers. The MFCV values obtained with normalized peak-averaging technique were compared to those obtained with the cross-correlation technique and examined by computer simulation of the MFCV distribution. The MFCV values obtained with normalized peak-averaging technique highly correlated with those obtained with cross-correlation technique in both EMG data 1 and EMG data 2. It was also confirmed that MFCV values obtained from EMG data 1 were distributed much more widely than those obtained from EMG data 2. These results show the clinical usefulness of normalized peak-averaging technique for the detailed assessment of MFCV.     

A four compartment open model with first-order absorption

This paper is related to the identification of pharmacokinetic parameters of a four-compartment open model with first order absorption from plasma level data. The eigenvalues of the characteristic matrix of the given system are obtained by transforming them into a single variable and the solution involves the minimization of the sum of squares of deviation of the model-predicted values of the state variables from an experimentally obtained values. The distribution volume and the lag time are also identified. Finally, the unicity of the absorption rate constant is obtained by the minimum energy principle. The results obtained with present method are compared with those obtained by the generalized least squares method.     

Dna Ploidy Studies of Benign and Malignant Tumours: Comparison of Flow Cytometry and Image Analysis Techniques Using Two Types of Cytological Specimen

DNA ploidy studies were carried out on Feulgen stained smears and cytocentrifuge preparations from 35 malignant tumours and four benign neoplasms using the CAS image analyser. The smears were prepared from scrapings from fresh tumour tissue whereas the cytocentrifuge preparations were prepared from single nuclear suspensions from paraffin-embedded cell blocks from the same tumour. Histograms obtained by image analysis of the tumour scrapes were compared with those obtained on the cytocentrifuge preparations. Concordant results were obtained in four benign tumours (100%) and 32 malignant tumours (91%). The results obtained by image analysis were also compared with results obtained by flow cytometry of the tumour tissue. Discordant results were obtained for three malignant tumours. Possible reasons for the discrepancy include sampling error, tumour heterogeneity and selective loss of cell populations during processing.     

Additional observations on the preparation of R banded human chromosomes with acridine orange.

A number of technical factors which affect acridine orange R banding (RFA banding) were studied. These variables included age of slide, timing of fixation, details of incubation mounting and the use of sequential technics. Optimal RFA banding was obtained between 15 and 20 days but good or very good preparations were obtained between 7 days and 2 months. Improved results were obtained in slides that were 3-4 months old by refixing the slides in ethanol acetic acid. Intermittent movement of slides during incubation in buffer as well as the details of mounting and removal of cover slips were found to be important. The best sequential banding was obtained with the sequence of Q to R but good results were obtained with the sequence G to R using ASG banding. Satisfactory results with the sequence R to C were not obtained. With careful attention to these variables good RFA binding can be obtained over a period of several months.     

Thermal inactivation of ileal loop-reactive Clostridium perfringens type A strains in phosphate buffer and beef gravy.

The thermal resistance of spore crops produced from each of two ileal loop-reactive strains of Clostridium perfringens type A was determined in two suspending vehicles consisting of 0.067 M (pH 7.0) phosphate buffer and a commercial beef gravy. D115.6 values obtained in buffer and enumerated after pretreatment with sodium ethylenediaminetetraacetate and recovery in plating medium containing lysozyme were two- to threefold greater than those obtained without this treatment. D115.6 values obtained with beef gravy were less than those obtained in buffer with or without lysozyme; however, the D98.9 and D104.4 values were 1.3 to 2 times greater than those obtained in buffer with lysozyme. The z values were within the ranges reported by previous investigators.     

Thermal inactivation of ileal loop-reactive Clostridium perfringens type A strains in phosphate buffer and beef gravy.

The thermal resistance of spore crops produced from each of two ileal loop-reactive strains of Clostridium perfringens type A was determined in two suspending vehicles consisting of 0.067 M (pH 7.0) phosphate buffer and a commercial beef gravy. D115.6 values obtained in buffer and enumerated after pretreatment with sodium ethylenediaminetetraacetate and recovery in plating medium containing lysozyme were two- to threefold greater than those obtained without this treatment. D115.6 values obtained with beef gravy were less than those obtained in buffer with or without lysozyme; however, the D98.9 and D104.4 values were 1.3 to 2 times greater than those obtained in buffer with lysozyme. The z values were within the ranges reported by previous investigators.     

Permeability properties of isolated enterocytes from rat small intestine

Metabolic and permeability properties of enterocytes isolated by treatment of rat small intestine with hyaluronidase or EDTA were compared. No significant difference was observed in the ability of the two types of cell to produce lactate from glucose. However, while cells obtained with hyaluronidase accumulate alpha-methylglucoside, cells obtained with EDTA were unable to accumulate the sugar above the medium concentrations. When resuspended in a medium designed to resemble the intracellular medium, potentiometric measurements showed that cells obtained with hyaluronidase released Ca2+ to the medium while cells obtained with EDTA accumulated it. Using 45Ca transport assays, this was shown to be an ATP-dependent process, the accumulated 45Ca being totally released by the addition of the ionophore A23187. When cells obtained with EDTA were resuspended in a medium containing concentrations of free Ca2+ higher that 10 microM, the uptake was partially inhibited by sodium orthovanadate and also by oligomycin and antimycin. At free Ca2+ concentrations lower than 1 microM, the accumulation was inhibited up to 87% by sodium orthovanadate while mitochondrial inhibitors inhibited only 5%. Thus, it appears that during their preparation cells obtained with hyaluronidase retain their integrity while cells obtained with EDTA become permeable to Ca2+ and other ions. The usefulness of both types of preparation in metabolic and transport studies is discussed.     

Synthesis of group-specific polysaccharide by different strains of Neisseria meningitidis serogroup B under various conditions

Sonicated lysates of 5 N. meningitidis strains, serogroup B, obtained from two solid serum-free culture media (a medium with casamino acids and a medium with Hottinger's hydrolysate) were studied with the aim of comparing the capacity of different group B meningococcal strains for the accumulation of group-specific polysaccharide. In the lysates obtained after 7-hour growth no sialic acid was found. After 20-hour cultivation, group-specific polysaccharide was detected in the lysates obtained from 4 out of 5 strains. All sonicated lysates obtained in these experiments were serologically active. The lysates obtained from the medium containing casamino acid had a higher content of group-specific polysaccharide. N. meningitidis strain 125, obtained at the Mechnikov Central Research Institute for Vaccines and Sera (Moscow) by selection, showed the highest content of capsular polysaccharide in microbial cells and the stable yield of biomass.     

Use of holographic laser interferometry to study the diffusion of polymers in gels

The aim of this study was to demonstrate the potential for holographic interferometry to be used for diffusion studies of large molecules in gels. The diffusion and partitioning of BSA (67,000 g/mol) and pullulans (5,900-112,000 g/mol) in agarose gel were investigated. The gel diffusion coefficients obtained for BSA were higher when distilled water was used as a solvent compared to those obtained with 0.1 M NaCl as the solvent. Furthermore, the gel diffusion coefficient increased with increasing BSA concentration. The same trend was found for liquid BSA diffusion coefficients obtained by DLS. BSA partition coefficients obtained at different agarose gel concentrations (2-6%, w/w) decreased slightly with increasing gel concentration. However, all BSA gel diffusion coefficients measured were significantly lower than those in pure solvent and they decreased with increasing agarose concentration. The gel diffusion coefficients obtained for pullulans decreased with increasing pullulan molecular weight. The same effect from increased molecular weight was seen in the liquid diffusion coefficients measured by DLS. The pullulan partition coefficients obtained decreased with increasing molecular weight. However, pullulans with a larger Stokes' radius than BSA had partition coefficients that were higher or approximately the same as BSA. This implied that the pullulan molecules were more flexible than the BSA molecules. The results obtained for BSA in this study agreed well with other experimental studies. In addition, the magnitude of the relative standard deviation was acceptable and in the same range as for many other methods. The results thereby obtained showed that holographic interferometry is a suitable method for studying diffusion of macromolecules in gels.     

The Distribution of Several Elements in Cat Urine and the Relation Between the Content of Elements and Urolithiasis

The concentrations of elements in urine obtained from cats with urolithiasis were compared with those of healthy cats. The concentration of several elements, such as sodium (Na), phosphorus (P), sulfur (S), and potassium (K), in urine obtained from cats with urolithiasis was significantly higher than that of healthy cats. A significant correlation (p<0.01) was found between the concentration of magnesium (Mg) and that of other elements, such as P (r=0.8913), S (r=0.6817), and K (r=0.8391), in the urine obtained from healthy cats. A significant correlation (r=0.7422, p<0.05) was also obtained between the concentration of K and that of P in urine collected from cats with urolithiasis, but the slope of regression line was significantly different from that of the urine obtained from healthy cats. Other correlations observed in healthy cats were not obtained from cats with urolithiasis. However, a significant correlation between the concentration of magnesium (Mg) and that of calcium was obtained only from cats with urolithiasis. The results of the present study suggest that urinary concentrations of various elements in cats with urolithiasis are higher than those of healthy cats. Furthermore, the balance of elements in the urine of cats with urolithiasis was altered.     

Nuclear changes in cytologic specimens obtained by CT-guided fine needle aspiration biopsies.

A light and electron microscopic study was conducted to investigate nuclear changes observed in specimens obtained from various sites by computed tomographic (CT)-guided fine needle aspiration (FNA) biopsy. These changes, which consisted of a disappearance of the nuclear chromatin and a disruption of the nuclear membrane, were found in 70% of 10 FNA specimens obtained with CT guidance, in 26% of 15 specimens obtained with fluoroscopic guidance and in 0% of 10 specimens obtained without x-ray imaging techniques. Although the number of cases studied was small and the mechanisms responsible for these changes are not clear, cytopathologists should be aware of alterations in evaluating FNA specimens obtained with the guidance of x-ray imaging techniques.     

黑刺菝葜根提取物的抑菌活性研究

以常见6种细菌和5种真菌为供试菌。采用滤纸片水平扩散法。对黑刺菝葜根的4种溶剂提取物和剩余水相大孔吸附树脂5种乙醇梯度洗脱物共9种提取物进行了室内抗菌生物活性测试,并对其主要的化学成分-常规的抗菌活性物质黄酮和甾体皂苷类化合物进行了定量测定。结果表明：黑刺菝葜根剩余水相大孔吸附树脂100％乙醇的洗脱物表现出极强的广谱性抗菌活性,80％乙醇的洗脱物对绿木霉、大肠杆菌显示出极强抑菌力;黑刺菝葜根的石油醚提取物、乙酸乙酯提取物和正丁醇提取物均对枯草芽孢杆菌、大肠杆菌显示较强的抗性;根的石油醚提取物和乙酸乙酯提取物对金黄色葡萄球菌、蜡状芽孢杆菌和巨大芽孢杆菌等有较强的抑制作用;根中所含的常规抑菌活性成分黄酮的含量为2．83％;甾体皂苷元的含量为4．55％。     

Assembly of microspheres from acidic proteinoids and histones or histone-like proteinoids

Basic polyamino acids, whether organismic or synthetic in origin, alter the morphology of proteinoid microspheres in which they are included. The particles obtained with histone are essentially indistirguishable under the light microscope from those obtained with proteinoids of histone-like composition (histonoids). In each instance, structures of morphological complexity similar to those of some microfossils are obtained.     

An accurate method for the quantitation of Fmoc-derivatized solid phase supports

Summary By performing the Fmoc resin loading determination with DBU instead of piperidine, highly reproducible results were obtained that showed excellent correlation with data obtained by independent analytical methods.     

Room-temperature chromatography of nucleic acids on hydroxylapatite columns in the presence of formamide

A method is described for performing hydroxylapatite chromatography at room temperature with elution buffers containing formamide. The salt and temperature elution chromatograms obtained by this method for single-stranded DNA, double-stranded DNA, and DNA-RNA hybrids give results similar to those obtained by standard hydroxylapatite techniques at elevated temperatures. Kinetic analysis of RNA-DNA hybridizations by room temperature by hydroxylapatite chromatography was compared with the data obtained by equilibrium centrifugation in Cs₂SO₄ gradients. The results obtained with the two methods were very similar.     

Polarization from a Helix of Fluorophores and its Relation to that Obtained from Muscle

Expressions for the polarization of fluorescence from fluorophores in a helical array have been obtained. These predictions have been compared with experimental data obtained by reacting fluorescent S-1 subfragments of myosin (extrinsically labeled with N-(iodoacetylaminoethyl)-5-napthylamine-1-sulfonic acid [1,5-IAEDANS]) with glycerated rabbit psoas fibers in rigor. A comparison with data obtained by directly labeling fibers with this fluorophore is also presented.