Ion chromatography: a new technique for clinical chemistry

Ion chromatography is a new analytical technique in which the ions to be analyzed are separated on a special pellicular ion-exchange column. Once separated, the effluent from the separating column passes into a second ion-exchange column, which removes the eluent or buffer ions from the moving phase without removing the sample ions, which are detected and measured by electrical conductivity on a background of low conductance. Trace quantities can be so determined. This technique has been applied to four biological fluids: blood serum, tissue extract, urine, and cerebrospinal fluid. It is shown to be a practical analytical tool, particularly for ions having no chromophores, such as sodium, ammonium, potassium, magensium, calcium, chloride, nitrite, phosphate, and sulfate.

Ion chromatography: a new technique for clinical chemistry

Ion chromatography is a new analytical technique in which the ions to be analyzed are separated on a special pellicular ion-exchange column. Once separated, the effluent from the separating column passes into a second ion-exchange column, which removes the eluent or buffer ions from the moving phase without removing the sample ions, which are detected and measured by electrical conductivity on a background of low conductance. Trace quantities can be so determined. This technique has been applied to four biological fluids: blood serum, tissue extract, urine, and cerebrospinal fluid. It is shown to be a practical analytical tool, particularly for ions having no chromophores, such as sodium, ammonium, potassium, magensium, calcium, chloride, nitrite, phosphate, and sulfate.

Horseradish peroxidase tracing of the lateral habenular-midbrain raphe nuclei connections in the rat

Connections of the habenular complex to the nuclei of the midline in the midbrain (interpeduncularis, medianus raphe, and dorsalis raphe) have been studied classically by anterograde degeneration in the monkey, the cat, and marsupials. Passing fibers from the medial septal nucleus and lateral preoptic area, however, have also been demonstrated which can complicate interpretation of these results. In this paper the habenular projections were studied in the rat by the retrograde axonal transport of horseradish peroxidase (HRP). After HRP injections in the medianus raphe nucleus labelled neurons appeared in the lateral habenular nucleus and parafascicular nucleus. Labelled neurons were also found in the lateral habenular nucleus after injections in either the dorsalis raphe nucleus or the caudal central gray substance. The habenular projections were always bilateral. There were no labelled neurons in the medial habenular nucleus after HRP injections in the medianus raphe especially on the dorsalis raphe neurons which have usually been thought of as functionally related to other brainstem structures. The present results suggest also that in the rat the lateral habenular nucleus might be the link between basal forbrain inputs and the limbic midbrain area. Thus, the raphe nuclei of the midbrain appear to be crucial regions for integrating two descending circuits: first, a limbic (through septum) circuit, and, second, a basal forebrain (through lateral habenular-preoptic area) circuit.

Profiles of couples seeking sex therapy and marital therapy

Assessment of 29 couples seeking marital therapy and 25 seeking sexual therapy at the same institution permitted the delineation of two distinct profiles. Although the two groups were similar in the degree of their sexual and marital difficulties and in demographic characteristics, the relationships of the sex therapy couples were generally characterized by satisfaction and affection, whereas those of the marital therapy couples were often antagonistic. In addition, the sex therapy couples tended to be less conservative and more thoughtful in their approach to life and their problems.

Characterization of an adenovirus early protein required for viral DNA replication: a single strand specific DNA binding proteins

1. The human adenoviruses types 2, 5 and 12 code for the production of a single strand specific DNA binding protein. The molecular weights of these proteins were 72,000 for types 2 and 5 and 60,000 for type 12. In all three cases proteolytic breakdown fragments of these binding proteins (48,000 MW) were also observed. 2. Analysis of the methionine containing tryptic peptides of these proteins indicate that the types 2 and 5 proteins are similar and clearly distinguishable from the type 12 protein. The peptide maps of these three viral proteins are clearly different from a similar protein found in mock infected cells. 3. Temperature sensitive mutants of type 5 (H5ts125) and type 12(H12tsA275) adenoviruses fail to produce these proteins at the nonpermissive temperature. H5ts125 infected cells grown at the permissive temperature produce a 72,000 MW protein that is thermolabile, for continued binding to DNA, when compared to type 5 wild type adenovirus 72,000 MW protein. An analysis of the phenotype of this adenovirus mutant indicates that it codes for a viral function at early times after infection that is required for viral DNA replication. 4. The in vitro translation of adenovirus specific m-RNA results in the synthesis of a small amount of a 72,000 MW protein that binds to single stranded DNA just like the authentic adenovirus DNA binding proteins produced in infected cells. 5. Adenovirus anti-Tumor antigen (T) anti-serum from hamsters carrying independently derived adenovirus tumors, have been tested for the presence of antibody to purified DNA binding proteins. One antiserum is positive for these antibodies while the other is negative. These results indicate that some, but not all, adenovirus tumors contain large enough levels of the DNA binding proteins to elicit an antibody response. 6. The type 5 adenovirus temperature sensitive mutant, H5ts125, that codes for a thermolabile DNA binding protein, was complemented or suppressed at the nonpermissive temperature, for the replication of adenovirus DNA, by SV40. SV40tsA temperature sensitive mutants, defective in SV40 DNA replication, do not suppress or complement H5ts125 at the nonpermissive temperature.

Sexual attitude reassessment workshops: effect on spinal cord injured adults, their partners and rehabilitation professionals

Five workshops, focused on the sexuality of adults with acquired spinal cord injuries, were offered for rehabilitation professionals and spinal cord injures adults between December 1971 and October 1972 by the University of Minnesota's Program in Human Sexuality and Department of Physical Medicine and Rehabilitation. The fifth workshop was jointly sponsored with the American Academy of Physical Medicine and Rehabilitation (AAPM&R) and included an optional third day on sexual counseling. The objectives of the workshops were to assist the professional to be more helpful with others and the disabled to be more helpful to themselves. These objectives were accomplished by demythologizing sexual behavior, desensationalizing sexual stimuli and aiding the disabled person and professional to come to an understanding and acceptance of the sexuality of themselves as well as others. Preworkshop, immediately postworkshop and follow-up questionnaires evaluated the effects of the seminars upon all participants: disabled, able-bodied, professional and nonprofessional. Of the 76 who returned anonymous questionnaires mailed to the 95 spinal cord injured adults and their partners, 96.0 per cent reported that they were gland they attended, 82.8 per cent stated that they were personally benefited and 90.8 per cent reported that they would recommend the program to others like themselves. Of the 168 signed evaluations, 119 were returned by the professional group. Of 112 indicating that they or their institutions were currently involved in providing sexual counseling and education to the physically disabled, 97.3 per cent reported that the University of Minnesota workshop had given ideas, impetus or form to the current effort. Sexual attitudes and attitude changes in the AAPM&R-sponsered workshop were similar to those measured in participants in other workshops involving medical and seminary students and community members. Further workshops have been planned based upon these results.

On the mechanism of action of clonidine: effects on single central neurones

1 Noradrenaline and clonidine were applied by microiontophoresis to single neurones in the cerebral cortex and medullary reticular formation of anaesthetized rats.2 Of a total of 247 neurones studied, 79% of medullary units and 60% of cortical units responded in the same manner to both noradrenaline and clonidine. The usual response was a depression of neuronal firing rate.3 It proved possible to antagonize some responses to both substances by the microiontophoresis of bulbocapnine, whilst leaving unaffected similar responses to 5-hydroxytryptamine.4 On 13% of the cells, clonidine produced an increase of firing rate. This effect could not be attributed to a post-synaptic antagonism of tonically released endogenous noradrenaline, but may indicate a presynaptic action of clonidine, reducing noradrenaline release.5 These observations are thought to support the idea that clonidine may have an agonist action on noradrenaline receptors in the brain.

Conditional lethal mutants of adenovirus 2-simian virus 40 hybrids. I. Host range mutants of Ad2+ND1

Human adenovirus type 2 (Ad2) grows poorly in monkey cells, although this defect can be overcome by co-infection with simian virus 40 (SV40). The nondefective Ad2-SV40 hybrid virus, Ad2(+)ND1, replicates efficiently in both human and African green monkey kidney cells, presumably due to the insertion of SV40 sequences into the Ad2 DNA. Several mutants of Ad2(+)ND1 have been isolated that grow and plaque poorly in monkey cells, although they retain the ability to replicate and plaque efficiently in HeLa cells. One of these mutants (H39) has been examined in detail. Studies comparing the DNA of the mutant with Ad2(+)ND1 either by the cleavage patterns produced by Escherichia coli R.RI restriction endonuclease digestion or by heteroduplexing reveal no differences. The pattern of protein synthesis of Ad2(+)ND1 and H39 in monkey cells is quite different with the mutant resembling Ad2, which is defective in the synthesis of late proteins. However, in human cells, the proteins synthesized by H39 and the parent Ad2(+)ND1 are very similar. The production of SV40 U antigen in H39-infected cells is different from that in Ad2(+)ND1-infected cells. Finally, the growth of H39 in monkey cells can be complemented by SV40.

Isolation and preliminary characterization of bacteriophages for Bdellovibrio bacteriovorus

Ten bacteriophages that attack and lyse saprophytic strains of Bdellovibrio bacteriovorus were isolated. Morphological, serological, and host-range studies revealed that there were four different bdellovibrio phages present among the isolates. One of the phages lysed a strain of B. bacteriovorus that requires the presence of a suitable bacterial host for growth. The phage attached to the bdellovibrio cells in the absence of the bacterial host cells; lysis occurred only in the presence of host cells. The 19 saprophytic bdellovibrio strains employed in the phage host-range studies were grouped on the basis of their susceptibility to phage lysis.