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An IgG1 type of protein with the genetic marker combination Gm(f), non a, and (x) has been described. The evidence from studies on isolated IgG1 Fc fragments showed that the IgG1 protein was of normal size. No Gm markers other than the three mentioned were found. Thus, there was no evidence for deletions or duplications giving rise to the unusual IgG1 protein. In contrast, the origin of the unusual genetic marker combination appears to be a rare IgG1 gene Gmf non a, x, probably due to an intragenic recombination at the IgG1 cistron. [ABSTRACT FROM AUTHOR]

An analysis was made of the induced changes in template properties of mature erythrocyte and liver chromatin which occur after extraction with 0.1 to 2.0 M NaCl pH 8.0. DNA-bound proteins soluble in acid at pH 1.0 and in phenol at pH 9.0 were identified by disc gel electrophoresis. Purified histones were added during the extraction regime to assess endogenous proteolyric activity and to serve as internal markers. Removal of proteins by 0.4 M NaCl from either chromatin resulted in little or no change in original template activity, solubility and thermal denaturation properties. Significant changes in these parameters were observed after extraction with NsCl ≥ 0.6 M. For liver chromatin, template activity and thermal melting properties gradually approached those of deproteinized DNA. The largest change occurred after the extraction of non-histone proteins which are not removed during 2.0-M NsCl treatment. In contrast, the largest single change in erythrocyte template properties occurred with 0.6-M NaCl treatment. At this salt concentration, erythrocyte template availability was the same as for liver chromatin. The only major component extracted was the erythrocyte specific histone, V or f2c. Annealing studies using saturating amounts of labelled RNA synthesized from the various types of chromatin confirmed the template activity studies. More of the DNA in chromatin appears to be transcribed as chromatin is extracted with increasingly higher concentrations of salt, with little indication that reassociation of protein and loss of transcripts occurs. Pre-saturation competition studies using [³H] synthesized from 0.6-M and 2.0-M salt-extracted chromatin indicates that histories are probably more important for maintaining the highly restricted template of the mature erythrocyte chromatin than for the more active template of liver chromatin. [ABSTRACT FROM AUTHOR]

Human peripheral lymphocyte preparations were tested with a mixed rosette method for the presence of lymphocytes bearing both the complement receptors characteristic of B lymphocytes, anti the capacity of T lymphocytes to spontaneously bind with sheep red blood cells (SR BC). The large and oval shaped pigeon red blood cells (PRBC) which do not form T-cell rosettes were utilized as indicators for rosette formation with the complement receptor-bearing B cell. In every individual (an average of 2.06%) lymphocytes were observed which formed rosettes with both SRBC' and PRBC indicators. These findings show that independent markers for both T and B cells may be present on the surface of the same lymphocytes. [ABSTRACT FROM AUTHOR]

The distribution of the functional group of the pH indicator bromthymol blue across the osmotic barrier component (or M phase) of the cristae membrane separating the inner from the outer aqueous phase of rat liver mitochondria has been measured by three partially independent methods. In mitochondria in State 5, under the usual conditions, only about one third of the total bromthymol blue reacts in the inner phase. In State 3, in presence of a high concentration of valinomycin in a KCl medium, approximately the same proportion of the bromthymol blue reacts in the inner phase as in State 5; but in State 4, practically all the bromthymol blue is expelled across the M phase and registers the pH of the outer phase. The bromthymol blue technique is incompetent to measure the pH of the inner phase of mitochondria in State 4; but a method is described that will permit the approximate quantitative measurement of the intramitochondria] pH from the light extinction of bromthymol blue in State 5 (or in State 3 in presence of valinomycin) provided that the distribution of the indicator and the internal and external buffering powers of the mitochondrial suspension are known. The expulsion of the bromthymol blue from the mitochondria in State 4 is attributable to the development of an electric potential across the M phase. [ABSTRACT FROM AUTHOR]

This article focuses on the essential biochemical, anatomical, physiological and genetic factors producing the hair's defect. The regulation of the human hair cycle is one of the most mysterious biological events. Hair follicles develop in the 2nd-5th month of intra-uterine life. This first pelage is shed in 7th-8th foetal month. After birth no new hair follicles are formed unless as a response to severe trauma. The scalp hair grows for 1000 days, and will then rest for 100 days. However, the cycle can vary from 120 days to 7 years. There are 80-90 hairs in anagen to every 10-20 hairs in telogen.