Investigation of mortality and morbidity associated with severe self-injurious behavior.

A retrospective study was conducted to determine whether severe self-injurious behavior was associated with shortened lengths of life or greater sensory impairments for Minnesota Regional Treatment Center residents with developmental disabilities. The client records of 209 institutionalized individuals who died between January 1, 1980, and December 31, 1989, were reviewed. The data revealed that the 29 clients who exhibited severe self-injury did not live significantly shorter lives compared to matched cohorts without self-injury. However, those clients with severe self-injury were found to have a significantly higher incidence of vision and hearing impairments than did the matched cohorts. Implications of these findings were discussed.

Human serum amyloid A genes are expressed in monocyte/macrophage cell lines.

Serum amyloid A (apoSAA) is a family of proteins found, mainly associated with high density lipoproteins, in the blood plasma of mammals and at least one avian species, the Pekin duck. These proteins are present in small amounts under normal circumstances, but their concentration is capable of rising 100- to 1,000-fold in situations involving tissue injury or infection. Like classic acute phase proteins they are produced in the liver; however, expression of one of the apoSAA genes is known to occur in activated macrophages of mice. We examined three human macrophage precursor cell lines (THP-1, U-937, and HL-60), before and after differentiation with phorbol 12-myristate 13-acetate or 1 alpha,25-dihydroxy-vitamin D3, for apoSAA messenger (m)-RNA expression and found that: 1) induction of steady-state apoSAA mRNA by lipopolysaccharide, interleukin-1, or interleukin-6 required the presence of the synthetic glucocorticoid dexamethasone; 2) the three known active genes, apoSAA1, apoSAA2, and apoSAA4, were induced in THP-1 cells, whereas the pseudogene apoSAA3 was not; 3) differentiated and undifferentiated THP-1 cells expressed apoSAA mRNA, but U-937 cells expressed apoSAA mRNA (low levels) only after phorbol 12-myristate 13-acetate differentiation and HL-60 cells did not express apoSAA mRNA whether differentiated or not; 4) apoSAA protein was detectable immunologically at a low level in lyophilized medium from induced THP-1 cells. Our findings are compatible with the hypotheses that 1) apoSAA gene expression in human monocytes/macrophages in vivo is differentiation dependent; 2) activated macrophages provide a local source of apoSAA at sites of tissue injury or inflammation; 3) apoSAA is induced in tissue macrophages by local stimuli, under conditions that may not evoke the systemic acute phase response.

Preservation of RNA for in situ hybridization: Carnoy's versus formaldehyde fixation.

Tissues fixed with organic solvent fixatives such as Carnoy's solution are known to give poor and erratic results with in situ hybridization, whereas those fixed with paraformaldehyde produce more consistent results. To understand this difference and to improve the utility of Carnoy's-fixed tissue for in situ hybridization, we explored several parameters of RNA integrity and preservation. Carnoy's-fixed, paraffin-embedded livers and paraformaldehyde-fixed, paraffin-embedded livers of mice were compared for RNA extractability, degradation, and hybridizability. In addition, retention of RNA in tissue sections after sequential in situ hybridization treatments was compared. RNA was found to be easily extractable from Carnoy's-fixed liver and was well preserved, with only slight degradation of high molecular weight RNA. Conversely, only a small percentage of the RNA was extractable from paraformaldehyde-fixed liver unless the tissue was digested with protease. The extracted RNA was well preserved, without detectable degradation. Sections of tissue fixed in Carnoy's solution subjected to in situ hybridization retained only about 10% of their original RNA content and gave correspondingly weak in situ hybridization signals. Formaldehyde-fixed tissues retained much more of the RNA (about 45%) and produced strong in situ hybridization signals. Treatment of Carnoy's-fixed tissue sections with vaporous formaldehyde increased retention of RNA and provided in situ hybridization signals comparable with those of paraformaldehyde-fixed tissues.

Stereotypic behavior of mentally retarded adults adjunctive to a positive reinforcement schedule.

Stereotypic behavior is one of the more common disturbed behaviors displayed by people who are developmentally disabled. This study evaluated the indirect effects on stereotypic frequency when the value of a concurrent fixed-interval reinforcement schedule for adaptive behavior was varied. Three profoundly mentally retarded adults performed a simple adaptive task reinforced under a fixed-interval schedule. The reinforcement schedule value was varied from fixed-interval 15 to 90, and 180 seconds after schedule control under each condition was demonstrated. The dependent measure was the frequency of stereotypic behavior. Stereotypic behavior increased in direct relation to the interval length. The theoretical and practical implications of treating stereotypies as an adjunctive behavior partially controlled by the reinforcement frequency for adaptive behaviors are discussed.

Amyloid protein SAA is an apoprotein of mouse plasma high density lipoprotein.

Mouse plasma contains a protein antigenically related to mouse protein AA, the principal protein derived from tissue deposits of amyloid substance in mice. In this work the plasma antigen, SAA, was found mainly as a high molecular weight form (2 x 10(5)) residing for the most part in the density interval 1.063-1.21 g/cm3 (high density lipoprotein, HDL); the largest amount of SAA, absolute and relative to total protein, was found in the density interval 1.125-12.1 g/cm3 (HDL3). When apoproteins of the mouse HDL obtained by delipidation of the lipoprotein particles were chromatographed in acid/urea, the antigenic activity appeared in the 10,000- to 15,000-dalton portion of the apoprotein complex. In these characteristics mouse SAA closely resembles human SAA and the behavior of the protein related to amyloid protein AA indicates that is one of the apoproteins of the HDL complex in both species. Therefore we suggest that it be named apoSAA.

Reliability of Estimates With Alternative Cluster Sizes in the Health InterviewSurvey.

The practice of grouping the elements of the universe of study into clusters and sampling the clusters is a common feature of sample designs. Dealing with clusters of elements ahnost invariably increases the sampling error of the statistics estimated from the sample. However, clustering usually reduces the per-unit costs of the sampling and data collection. As the cluster size is increased, the costs of conducting a survey are usually reduced but the sampling errors of the statistics generally increase for a given sample size. The increase in variance due to clustering may be considered as a "loss" in the reliability of a statistic. The purpose of this study is to obtain measurements of the loss in reliability due to clustering of households using various cluster sizes for data collected by the Health Interview Survey (HIS).