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Biomedical subjects

R C Schwartz

Publications and source records attributed to R C Schwartz.

At least 19 recordsLinked to original sources
PubMed2005

Phosphorus extractability of soils amended with stockpiled and composted cattle manure.

Managing fertilizer applications to maintain soil P below environmentally unacceptable levels should consider the contribution of manure and synthetic fertilizer sources to soluble and extractable forms of P. Our objective was to evaluate soil and manure characteristics and application rates on P extractability in recently amended soils. Five soils of the U.S. southern High Plains were amended with beef cattle manures, composted beef manure, and inorganic fertilizers [Ca(H(2)PO(4))(2) or KH(2)PO(4)] at five rates and incubated under controlled conditions. Mehlich 3-, Olsen (NaHCO(3))-, Texas A&M extractant (TAM)-, and water-extractable P were determined for the soils after selected incubation periods. Except for TAM and some water extractions, P extractability as a function of total P applied was linear (P < 0.001) for a wide range of application rates. Mehlich-3, NaHCO(3), and water P extraction efficiencies of KH(2)PO(4)-amended soils averaged 22, 34, and 115% greater (P < or = 0.036), respectively, than efficiencies of soils amended with manures except for the Texline (calcareous) loam and Pullman clay loam soils. Phosphorus extraction efficiencies decreased with time for KH(2)PO(4)-amended soils (P < 0.05) but remained stable or increased for manure-amended soils during the 8-wk incubation period. Across all soils and manure sources, changes in water-extractable P per unit increase in Mehlich 3-, NaHCO(3)-, and TAM-extractable P averaged 100, 85, and 125% greater, respectively, for inorganic as compared with manure-amended soils. These source-dependent relationships limit the use of agronomic soil extractants to make correct inferences about water-extractable P and dissolved P in runoff.

Animals↗
PubMed2001

Superinduction of TNF-alpha and IL-6 in macrophages by vomitoxin (deoxynivalenol) modulated by mRNA stabilization.

Vomitoxin (VT or deoxynivalenol), a trichothecene, superinduces proinflammatory cytokine gene expression in vitro and in vivo. To better understand the underlying molecular mechanisms for this observation, post-transcriptional effects of VT on TNF-alpha and IL-6 gene expression were studied in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. VT was found to enhance both TNF-alpha and IL-6 protein secretion in the presence of LPS. Upon addition of the transcriptional inhibitor, 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole (DRB), secretion of both cytokines was inhibited. Using Northern analysis, the mRNA stabilities of TNF-alpha and IL-6 were studied in DRB-treated cells exposed to VT and LPS in both asynchronous and delayed synchronous modes. In the asynchronous model, cells were first incubated with LPS for 2 h, and then the medium was removed and replaced with medium containing DRB and VT. In the delayed synchronous model, cells were pretreated with LPS for 2 h and then DRB and VT were added to the culture. TNF-alpha and IL-6 mRNA were rapidly stabilized by VT (100 and 250 ng/ml) in both asynchronous and delayed synchronous models. In the asynchronous model, TNF-alpha mRNA half-life was 25 min but this was extended in the presence of 100 and 250 ng/ml of VT to >3 h. VT also extended half-lives of IL-6 mRNA from 60 min to >3 h. In the delayed synchronous model, the half-lives for TNF-alpha and IL-6 mRNA of 1.3 and 1.5 h, respectively, were extended to >3 h upon incubation with 100 and 250 ng/ml VT. These results suggest that post-transcriptional control via enhancement of mRNA stability is likely to contribute to proinflammatory cytokine superinduction in macrophages by VT and other trichothecenes.

Analysis of Variance↗
PubMed2001

Predictors of homicidal ideation and intent in schizophrenia: an empirical study.

Correlations of age, gender, and psychosocial variables with ratings of current homicidal ideation and intent were investigated among psychiatric facility clients with schizophrenia. Multiple regression analyses revealed, irrespective of age or gender, significantly positive correlations of three psychosocial variables--manic symptoms, psychotic symptoms, and impaired global functioning--with homicidal ideation and intent. Implications for research are discussed.

Adolescent↗
PubMed2001

Physical illness: social construction or biological imperative?

All cultures have metaphors for mental illness that define how it is diagnosed, treated, and experienced by the patient. Cultural metaphors that define mental illness have been traced predominantly to biomedical and systems models. However, the research on factors such as progression of illness, survival rates, adherence to medical regimens, level of disability, and experience of pain in chronic and acute life-threatening illnesses suggests another metaphor. This article not only explores how a constructivist metaphor makes sense of this research, but also suggests an approach to consider in helping patients and their families deal with the difficult life circumstances that illness imposes. Implications for nurses are outlined.

Culture↗
PubMed2000

Autosomal dominant Emery-Dreifuss dystrophy due to mutations in rod domain of the lamin A/C gene.

BACKGROUND: Autosomal dominant Emery-Dreifuss muscular dystrophy (EDMD-AD) is a disorder characterized clinically by humeropelvic weakness, contractures, and cardiomyopathy, and genetically by mutations in the lamin A/C gene on 1q21.2-q21.3. Of the 14 lamin A/C gene mutations reported thus far, the four involving the rod domain have been associated with isolated cardiomyopathy and conduction-system disease. This is the first report of rod domain mutations in patients with the full EDMD-AD phenotype. METHODS: Clinical, pathologic, and genetic data are provided on two families with EDMD-AD. RESULTS: In both families, the full clinical spectrum of EDMD-AD was demonstrated. For the proband in family 1, sequence analysis detected a mutation within exon 2 of the lamin A/C gene. The missense mutation was due to a A448C base substitution causing a Thr150Pro amino acid change. For the proband of family 2, sequence analysis detected an in-frame 3-bp deletion (AAG 778-780 or 781-783) removing one of two adjacent lysine residues (K 260 or 261) of exon 4. Both mutations were in the central rod domain of the lamin A/C gene. CONCLUSIONS: Mutations in the rod domain of the lamin A/C gene may cause the full clinical spectrum of EDMD-AD.

Adolescent↗
PubMed2000

The C/EBP bZIP domain can mediate lipopolysaccharide induction of the proinflammatory cytokines interleukin-6 and monocyte chemoattractant protein-1.

C/EBPalpha, beta, and delta are all expressed by bone marrow-derived macrophages. Ectopic expression of any of these transcription factors is sufficient to confer lipopolysaccharide (LPS)-inducible expression of interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) to a B lymphoblast cell line, which normally lacks C/EBP factors and does not display LPS induction of proinflammatory cytokines. Thus, the activities of C/EBPalpha, beta, and delta are redundant in regard to expression of IL-6 and MCP-1. Surprisingly, the bZIP region of C/EBPbeta, which lacks any previously described activation domains, can also confer LPS-inducible expression of IL-6 and MCP-1 in stable transfectants. Transient transfections reveal that the bZIP regions of C/EBPbeta, C/EBPdelta, and, to a lesser extent, C/EBPalpha can activate the IL-6 promoter and augment its induction by LPS. Furthermore, the transdominant inhibitor, LIP, can activate expression from the IL-6 promoter. The ability of the C/EBPbeta bZIP region to activate the IL-6 promoter in transient transfections is completely dependent upon an intact NF-kappaB-binding site, supporting a model where the bZIP protein primarily functions to augment the activity of NF-kappaB. Replacement of the leucine zipper of C/EBPbeta with that of GCN4 yields a chimeric protein that can dimerize and specifically bind to a C/EBP consensus sequence, but shows a markedly reduced ability to activate IL-6 and MCP-1 expression. These results implicate the leucine zipper domain in some function other than dimerization with known C/EBP family members, and suggest that C/EBP redundancy in regulating cytokine expression may result from their highly related bZIP regions.

Animals↗
PubMed2000

Critique of recent empirical research on insight and symptomatology in schizophrenia.

During the past decade there has been a resurgence of interest in investigating the relationship between insight and symptomatology among clients with schizophrenia. The breadth and depth of the articles have dramatically increased over the past 10 years, including the number of empirical research studies. This article summarizes the strengths and limitations of the empirical research focused on the association between insight and severity of psychotic symptoms and published between 1990 and 1999.

Awareness↗
PubMed1999

Reliability and validity of the functional assessment rating scale.

The Functional Assessment Rating Scale was developed as a measure of psychiatric symptomatology and psychosocial impairments. This study was designed to report estimates of reliability and validity with a population of schizophrenic patients. The scale showed very good interrater agreement, test-retest reliability, construct validity, and concurrent validity, so the scale seems a useful measure of psychopathology which may be used to assess and monitor patients displaying severe mental illnesses.

Antisocial Personality Disorder↗
PubMed1999

Correlates of empathic understanding among neophyte trainees in psychotherapy.

Results are summarized of an empirical study testing the associations among various academic, demographic, and personal characteristics and rated empathic understanding among 93 neophyte psychotherapy trainees from six universities. Multiple regression analyses suggested that completion of a graduate group counseling course with a specific personal growth component was the only characteristic significantly correlated with ratings of empathic understanding.

Adult↗
PubMed1998

Autocrine signals control CCAAT/enhancer binding protein beta expression, localization, and activity in macrophages.

The transcription factor CCAAT/enhancer binding protein beta (C/EBPbeta, or NF-IL6) is expressed in macrophages, where it participates in lipopolysaccharide (LPS)-mediated induction of proinflammatory cytokine genes such as interleukin-6 (IL-6) and IL-1beta. We have identified activities in conditioned medium from a macrophage tumor cell line that regulates the expression, localization, and transcriptional activity of C/EBPbeta. One factor was shown to be tumor necrosis factor- (TNF-), which increased C/EBPbeta expression by a posttranscriptional mechanism. A second activity, designated autocrine macrophage factor (AMF), elicited a change in C/EBPbeta localization from a punctate nuclear staining pattern to diffuse nuclear distribution. The punctate form of C/EBPbeta correlated with increased susceptibility of this protein to cleavage by an endogenous protease during nuclear extract preparation. Conditioned medium stimulated the ability of C/EBPbeta to transactivate a reporter gene and activated the expression of two cytokine genes that are putative targets of C/EBPbeta. These observations suggest that diffuse distribution of C/EBPbeta in the nucleus corresponds to an activated form of this protein. AMF activity could not be mimicked by an extensive set of recombinant cytokines and growth factors and therefore may represent a novel extracellular factor.

Animals↗
PubMed1998

C/EBPepsilon is a myeloid-specific activator of cytokine, chemokine, and macrophage-colony-stimulating factor receptor genes.

C/EBPepsilon is a member of the CCAAT/enhancer binding protein family of basic region/leucine zipper transcriptional activators. The C/EBPepsilon protein is highly conserved between rodents and humans, and its domain structure is very similar to C/EBPalpha. In mice C/EBPepsilon mRNA is only detected in hematopoietic tissues, including embryonic liver and adult bone marrow and spleen. Within the hematopoietic system, C/EBPepsilon is expressed primarily in myeloid cells, including promyelocytes, myelomonocytes, and their differentiated progeny. To identify potential functions of C/EBPepsilon, cell lines over-expressing the C/EBPepsilon protein were generated in the P388 lymphoblastic cell line. In contrast to the parental cell line, C/EBPepsilon-expressing cell lines displayed lipopolysaccharide-inducible expression of the interleukin-6 and monocyte chemoattractant protein 1 (MCP-1) genes as well as elevated basal expression of the MIP-1alpha and MIP-1beta chemokine genes. In the EML-C1 hematopoietic stem cell line, C/EBPepsilon mRNA levels increased as the cells progressed along the myeloid lineage, just preceding activation of the gene encoding the receptor for macrophage-colony-stimulating factor (M-CSFR). M-CSFR expression was stimulated in C/EBPepsilon-expressing P388 cell lines, when compared with either the parental P388 cells or P388 cell lines expressing either C/EBPalpha or C/EBPbeta. These results suggest that C/EBPepsilon may be an important regulator of differentiation of a subset of myeloid cell types and may also participate in the regulation of cytokine gene expression in mature cells.

Amino Acid Sequence↗
PubMed1998

Redundancy of C/EBP alpha, -beta, and -delta in supporting the lipopolysaccharide-induced transcription of IL-6 and monocyte chemoattractant protein-1.

C/EBP alpha, -beta, and -delta are members of the CCAAT/enhancer binding protein family of transcriptional regulators. All three of these factors are expressed by bone marrow-derived macrophages, with the DNA binding activity of C/EBP beta and -delta increased by treatment with LPS while that of C/EBP alpha is decreased. We have ectopically expressed each C/EBP protein in P388 lymphoblasts. The expression of any of these transcription factors is sufficient to confer the LPS-inducible expression of IL-6 and monocyte chemoattractant protein-1 to lymphoblasts, which normally lack C/EBP factors and do not display LPS induction of proinflammatory cytokines. Thus, the activities of C/EBP alpha, -beta, and -delta are redundant in regard to the expression of IL-6 and monocyte chemoattractant protein-1. Since C/EBP beta-deficient mice have been reported to be largely normal in their expression of proinflammatory cytokines, it is likely that the lack of C/EBP beta is compensated for by the induction of C/EBP delta upon LPS treatment.

Adjuvants, Immunologic↗