Proposal of standardized methods and reference for assaying recombinant human tumor necrosis factor

Two assay methods for recombinant human tumor necrosis factor (rH-TNF) were developed, one a biological L-cell assay and the other an enzyme-linked immunosorbent assay. The accuracy and reproducibility of each and the correlation between the two were studied. As a result of this investigation, the two assay methods were found appropriate for standardization of rH-TNF. A freeze-dried reference was prepared, and examination of its potency and stability showed it to be suitable for use as a reference standard for rH-TNF assays.     

Fluorescence lifetime reference standards for the range 0.189 to 115 nanoseconds

A review of the modern literature reveals that the values for quinine fluorescence lifetime are in good agreement, the mean value being 18.91±0.56 nsec. By virtue of some very unusual properties, quinine appears suitable for use as a lifetime reference standard for any value from 0.189 to 18.9 nsec, with an expected accuracy of ±3% throughout this range. Cl^?, not normally considered a quenching agent, quenches quinine emission at diffusion-controlled rates. The Stern-Volmer plot was unique in that the strict lincarity, indicating pure collisional quenching, was maintained even when fluorescence was > 99% quenched. Thus, solutions of quinine-NaCl can be made up having lifetimes known to great accuracy. Similarly, γ-pyrenebutyrate solutions containing KI are suitable standards for the range up to 115 nsec. The compositions of such solutions have been calculated and tabulated. It is argued that the lifetimes of these solutions are at least as reliable as any of the hundreds of lifetimes which have been reported in the literature. Several important applications of such lifetime standards are discussed.     

A new rig for standardized craniofacial photography put to the test

This article describes and tests a photography rig that has been built at the University of Melbourne, Australia, specifically for the purpose of taking rapid and highly standardized craniofacial photographs, in simultaneous views of front and profile. The rig uses a novel projected light range-finding system that has been designed for easy and accurate positioning of subjects, in the natural head position, at precise distances from the frontal camera. Results of experiments examining the intraobserver error of multiple photographs taken on the rig indicate that high-quality, repeatable photographs can be taken after a reasonably large amount of time has lapsed between photography sessions (e.g., 30 days). This study also indicates that some variability remains between photographs even when highly standardized protocols are followed. Consequently, it is expected that the variation between photographs with limited standardization is much larger and more likely to cause significant errors in any comparisons.     

Proposal for using tissue culture for the potency test of smallpox vaccine

In this report are compared the results of various titrations of a single lot of smallpox vaccine performed both in eggs and in tissue cultures. The titre of the vaccine expressed as pock-forming units in eggs was greatly dependent on the choice of the virus dilution. The end-point technique in tissue cultures seemed to be more accurate and reliable, so that this titration procedure could be officially recommended.     

Cytological studies of ameiotic and normal maize with reference to premeiotic pairing

This study reports cytological observations in maize plants homozygous for the recessive am allele which suppresses meiosis in both male and female meiocytes. The ultimate premeiotic mitosis in anthers from ameiotic plants is normal, but the resulting nuclei do not undergo meiosis. Instead, a synchronized mitosis occurs after which the cells degenerate. No evidence was found for a non-random association of homologous chromosomes in the premeiotic or ameiotic mitoses of homozygous ameiotic plants or in the premeiotic mitosis of normal sibs. These observations are in agreement with the classical view that synapsis of homologous chromosomes does not occur until zygotene.     

Mixed-model analysis of a censored normal distribution with reference to animal breeding

A mixed-model procedure for analysis of censored data assuming a multivariate normal distribution is described. A Bayesian framework is adopted which allows for estimation of fixed effects and variance components and prediction of random effects when records are left-censored. The procedure can be extended to right- and two-tailed censoring. The model employed is a generalized linear model, and the estimation equations resemble those arising in analysis of multivariate normal or categorical data with threshold models. Estimates of variance components are obtained using expressions similar to those employed in the EM algorithm for restricted maximum likelihood (REML) estimation under normality.     

The creation of a test system for detecting Mycoplasma pneumoniae based on a method of directed DNA amplification]

A system for the rapid detection of M. pneumoniae, the causative agent of pneumonia in humans, has been developed. This system is based on the amplification of M. pneumoniae chromosomal DNA sequences in the polymerase chain reaction (PCR). The use of two primer sets, for nucleotide sequences of adhesion protein P1 and for nucleotide sequences of variable regions of the 16S ribosomal RNA, has permitted the detection of individual M. pneumoniae cells. The application of this technique for the study of simulated clinical material has shown that PRC is a sensitive and reliable assay and may be useful for the early detection of M. pneumoniae in infectious clinical material (blood and sputum samples).     

Results of bicondylar sledge prostheses with special reference to the gait pattern]

AIM: To establish whether the clinical results obtained with bicondylar sledge prostheses correlate with clinical findings, and whether clinical results influence gait pattern. MATERIAL AND METHODS: 15 patients with bicondylar sledge prostheses were compared with healthy controls. The clinical examination was documented using the HSS, Knee Society, Tegner, and patella scores, and the Visual Analogue Scale. Gait analysis was done with a three-dimensional motion analysis system and force platforms. RESULTS: A comparison of patients and controls showed significant differences in the clinical results, whereas the parameters gait function, muscle force and pain did not. No significant differences were found between the operated and non-operated legs. In comparison with controls, patients showed significant differences in the ground reaction forces. DISCUSSION: The abnormal gait findings showed no correlation with clinical results, nor did such parameters as age, weight and duration of follow-up appear to have any influence. The non-operated leg adapted to the gait pattern of the operated leg, to restore gait symmetry. CLINICAL RELEVANCE: Subjective complaints or clinical results show little relationship to gait parameters in patients receiving a bicondylar sledge prosthesis.     

N.m.r. and e.p.r. characterization of [4-carboxy-2,6-dinitrophenyl-lysine]cytochromes c.

Monosubstituted [4-carboxy-2,6-dinitrophenyl-lysine]cytochromes c were investigated by n.m.r. and e.p.r. Modification of Lys-13 or Lys-72 in ferricytochrome c by 4-chloro-3,5-dinitrobenzoate yields either of two different conformers that are rapidly exchanging in the native form. The equilibrium involves small local changes in the conformation of Met-80 (the sixth ligand) and Phe-82, as a result of whether Lys-13 is the 'on' or 'off' position in the Lys-13--Glu-90 salt bridge.     

Physiology of vertebrates under micro-gravity with special reference to the Ca metabolism]

On April 12, 1961, Major Yurii A. Gagarin of the former-U.S.S.R. Air Force circled the Earth in a spacecraft named "Vostok", a word which means "east". He spent 1 hour and 48 minutes in space. Since then, the U.S.S.R. and the U.S.A. have sent many astronauts into space. In one case, the stay in space exceeded a year in length, reaching 438 days. Through these experiences, it became clear that micro-gravity caused various problems in human physiology. One of the most serious problems was the loss of Ca from bones, as a result of the negative expenditure of Ca. Under 1G on the ground, bone absorption and bone formation proceed in accordance. Under micro-gravity, however, this balance is broken. Although this phenomenon has been widely analyzed from the viewpoint of molecular biology as well, studies to clarify the mechanism that causes the disorder of Ca metabolism in bones have just started. At present, no perfect treatment to prevent the loss of Ca from bones is available.     

Studies on mycobacteria isolated from animals, with special reference to the agglutination test

Ninety-three strains of slowly-growing mycobacteria were studied biochemically. Ninety of these were isolated from animals (pigs, cattle, dog and poultry) and three from dust and sawdust-bedding in a pighouse. One strain from a lymph node of a pig was identified as M. gordonae. Ninety-two strains fitted into the M. aviam-intracellulare complex. Of the 92 biochemically confirmed M. avium-intracellulare strains, 78 were tested serologically ad modum Schaefer. Of 73 strains from pigs, one was serotype 1, fifty serotype 2 and eight serotype 8, while two could not be type and twelve were autoagglutinable. Three strains from pighouse environment were serotype 8 and two from cattle and a dog were both serotype 2. A slight modification of Schaefer's agglutination method, using smaller amounts of antigen and antiserum, was developed.     

Characterization of glycosaminoglycans from human normal and scoliotic nasal cartilage with particular reference to dermatan sulfate.

The composition and the distribution of glycosaminoglycans (GAGs) present in normal human nasal cartilage (HNNC), were examined and compared with those in human scoliotic nasal cartilage (HSNC). In both tissues, hyaluronan (HA), keratan sulfate (KS) and the galactosaminoglycans (GalAGs)--chondroitin sulfate (CS) and dermatan sulfate (DS)--were identified. The overall GAG content in HSNC was approx. 30% higher than the HNNC. Particularly, a 114% increase in HA, and 46% and 86% in KS and DS, respectively, was recorded. CS was the main type of GAG in both tissues with no significant compositional difference. GalAG chains in HSNC exhibited an altered disaccharide composition which was associated with significant increases of non-sulfated and 6-sulfated disaccharides. DS, which was identified and quantitated for the first time in HNNC and HSNC, contained low amounts of iduronic acid (IdoA), 18% and 28% respectively. In contrast to other tissues, where IdoA residues are organized in long IdoA rich repeats, the IdoA residues of DS in human nasal cartilage seemed to be randomly distributed along the chain. DS chains in HSNC were of larger average molecular size than those from HNNC. These results clearly indicate the GAG content and pattern in both HNNC and HSNC and demonstrate that scoliosis of nasal septum cartilage is related to quantitative and structural modifications at the GAG level.