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D J Hartmann

Publications and source records attributed to D J Hartmann.

At least 37 records · Page 2Linked to original sources
PubMed1995

Imbalance between 95 kDa type IV collagenase and tissue inhibitor of metalloproteinases in sputum of patients with cystic fibrosis.

A growing body of evidence suggests that neutrophil-derived proteinases play a major role in lung tissue damage in cystic fibrosis (CF). Most previous studies have focused on serine proteinases such as neutrophil elastase, providing no information on the extent to which metalloproteinases participate in proteolytic processes in CF. To address this issue, we evaluated the contribution of one of the major neutrophil metalloproteinases, i.e., 95 kDa gelatinase (type IV collagenase), to the total gelatinolytic activity measured in sputum specimens from 27 patients with CF. Compared with asthmatic children (n = 9), CF patients had a 6.7 times greater level of total gelatinase activity in sputum revealed by zymography. The 95 kDa gelatinase was increased 3.7-fold in the CF subjects (2,441 +/- 411 [SEM] arbitrary units [AU] x 10(6) per ml of sputum versus 665 +/- 201 in asthmatics) and the 88-kDa active form 23.2-fold (2,272 +/- 372 AU x 10(6) per ml of sputum versus 98 +/- 43, respectively). Using radiolabeled 3H-gelatin as the substrate, we demonstrated uninhibited gelatinolytic activity in all CF patients; this activity was significantly correlated to disease severity as assessed by pulmonary function tests. Western blotting using anti-tissue inhibitor of metalloproteinase (anti-TIMP) and anti-95/88-kDa gelatinase antibodies demonstrated a more than 10-fold excess of 95/88 kDa gelatinase over TIMP. Bacterial proteinases from Pseudomonas aeruginosa were shown to contribute little to the gelatinolytic activity measured in sputum supernatants from patients with CF, although culture supernatants from various P. aeruginosa strains expressed gelatinolytic activity in vitro. Finally, lung damage, as assessed by increased type IV collagen degradation products in sputum, was significantly correlated to concentrations of active 88 kDa gelatinase. These data argue for a significant role of 95/88 kDa gelatinase in airway damage in CF.

Adolescent↗
PubMed1995

Ultrastructural characterization of mesenchymal and epithelial cells co-cultured from human dental root apical explants.

Previous studies have shown the role of cell-cell and cell-matrix interactions in the differentiation of the specific secretory cells of the tooth. In order to elucidate the mechanisms implicated in root dentin formation, we developed a co-culture system of human pulpal mesenchymal and epithelial root sheath cells. Root tips of premolars were cultured in Eagle's basal Medium supplemented with fetal calf serum, ascorbic acid, antibiotics and, for some of them, with sodium beta-glycerophosphate. After 60 days of culture, cells were prepared for light and electron microscopy. Three main cell types were observed: (1) polygonal mesenchymal cells showing a functional polarity and producing a dense network of tactoid collagenous fibers. The latter had a specific circular organization that delimited small lacunae around the cells and mineralized in the presence of beta-glycerophosphate; (2) spindle-shaped mesenchymal cells mainly localized inside epithelial-mesenchymal knots and synthesizing an abundant collagenous matrix; and (3) epithelial cells lying on the plastic culture dish, on the dense collagenous matrix, or on spindle-shaped cells. Epithelial cells deposited a structured basement membrane when they were lying on the plastic culture dish or on spindle-shaped cells. On the contrary, no basement membrane was found when epithelial cells were overlying the dense collagenous network. Immunoelectron microscopic analysis of type IV collagen and laminin indicated that these two specific basement membrane components were produced by all cell types. These results show that the co-culture system should be valuable for (1) studying the in vitro formation of human dental root hard tissues, (2) characterizing cell-cell and cell-matrix interactions implicated in dental basement membrane production, and (3) isolating populations of cells implicated in dental root formation.

Adolescent↗
PubMed1995

Ultrastructural Localization of elastin-like immunoreactivity in the extracellular matrix around human small lymphatic vessels.

The distribution of elastin-like immunoreactivity around small lymphatic vessels was investigated in three different human tissues (skin, heart and dental pulp) using high resolution immunocytochemistry. Quantitative assessment of the immunogold reaction was performed with an image analysis system. Intense and moderate elastin-immuno-reactivity was detected in the extracellular matrix around small lymphatic vessels of the skin and heart, respectively. By contrast, absence of immunostaining was observed around lymphatic vessels in the dental pulp. Although the staining was mostly detectable on the non-fibrillar amorphous component of the extracellular matrix, some microfibrils were also immunostained in close proximity to the lymphatic vessel wall. These findings support the concept that small lymphatic vessels may be heterogeneous with respect to the composition of the extracellular matrix around their wall. The observation that it is possible to observe small lymphatic vessels displaying low or no elastin-immunoreactivity in the adjoining matrix militates against the hypothesis that elastic fibers play a pivotal role in the mechanisms that regulate the function of small lymphatic vessels.

Elastin↗
PubMed1994

Transforming growth factor beta 1 stimulates type V collagen expression in bovine vascular smooth muscle cells.

Vascular smooth muscle cells (SMCs) produce the bulk of the connective tissue of major arteries, including collagen types I, III, and V. Recently, we have shown, they also have the capacity to synthesize the alpha 1 chain of type XI, a collagen related to type V (Brown, K., Lawrence, R., and Sonenshein, G. (1991) J. Biol. Chem. 266, 23268-23273). Furthermore, expression of types V and XI collagen were coordinately regulated with respect to serum deprivation and cell density in a fashion distinct from that for types I and III. To begin to determine the factors that influence vascular SMC production of types V/XI collagen, we have examined the effects of transforming growth factor (TGF)-beta 1, a major modulator of connective tissue expression. In serum-deprived confluent cultures of bovine pulmonary artery SMCs, TGF-beta 1 treatment increased the steady-state levels of the mRNAs of collagen types V and XI, as well as of types I and III, elastin and fibronectin. The largest increase was seen for alpha 2(V) procollagen. The increase in alpha 2(V) mRNA was detectable by 12 h after addition of 2 ng/ml TGF-beta 1, and concentrations as little as 0.5 ng/ml were effective. A similar increase in alpha 2(V) mRNA levels was observed with SMCs derived from the aortic arch and carotid artery. Type V collagen protein was found to be elevated by TGF-beta 1 treatment in both the conditioned media and the cell layer associated fraction of pulse-labeled cultures. A slight decrease in SMC proliferation as judged by DNA content, [3H]thymidine incorporation, and steady-state levels of histone H3.2 mRNA resulted from TGF-beta 1 treatment. These results suggest that the elevated levels of TGF-beta 1 in the vessel wall during atherosclerosis may be, in part, responsible for the increase in type V collagen that typifies advanced fibrotic lesions.

Animals↗
PubMed1994

Qualitative study of collagenous and noncollagenous glycoproteins of the human healthy keratinized mucosa surrounding implants.

The purpose of this study was to analyse the distribution of interstitial collagenous and noncollagenous glycoproteins of keratinized mucosa surrounding successful endosseous implants. Biopsies were incubated with highly purified antibodies against types I, III, IV collagen, laminin and fibronectin and routinely observed by immunofluorescence staining. Whereas no significative difference in the distribution of collagenous components was observed in comparison with healthy human gingiva, the collagen fibers of the connective tissue attachment ran parallel to the long axis of the implant. In 50% of the biopsies the gingival connective tissue underlying the junctional epithelium was rich in inflammatory cells and poor in collagenous components. However, the increased staining of type III collagen and the intense presence of fibronectin in this area reflect the very important remodeling ability of the local keratinized mucosa.

Collagen↗
PubMed1994

[Significance of type III serum N-terminal peptide procollagen assay in chronic viral hepatitis C].

The aim of this study was to evaluate the relationship between the serum N-terminal peptide of type III procollagen (PIIINP), Knodell's score and the response to treatment in 79 patients with viral C chronic hepatitis. Liver biopsy and serum PIIINP was assessed in all patients. Serum PIIINP was correlated with Knodell'score (r = 0.60; P = 10(-4)). Correlation between serum alanine amino-transferase and Knodell'score was smaller than for PIIINP (r = 0.38; P = 0.02). Forty-nine patients were treated with interferon alpha. A second biopsy and serum PIIINP determination were performed one year after treatment discontinuation. Means of serum PIIINP and Knodell'score significantly decreased after treatment (P < 0.01; P < 0.03). Among non-responder patients, serum PIIINP was initially more elevated: 37.5 +/- 12.6 ng/mL versus 22.6 +/- 3.8 (P < 10(-3)). Knodell's score decreased only among responder patients (P < 0.01 vs P < 0.7). Positive and negative predictive value for the response to treatment, evaluated by aminotransferases normalization, of serum PIIINP level < or = 24 ng/mL were 0.6 and 0.9 respectively. These findings suggest that serum PIIINP is a relevant marker of activity in patients with viral C chronic hepatitis and that it might have a predictive value of response to treatment.

Adult↗
PubMed1994

The managerial nature of case management.

Case managers have been viewed as engaging in direct practice, community practice, or both. This article offers a third view: Case managers also engage in the practice of management. Employing Mintzberg's seminal research on chief executive behavior, the authors argue that case managers' work is similarly characterized by brevity, variety, and fragmentation. Case managers perform the 10 roles developed in Mintzberg's original study. These roles are divided into three groups: interpersonal, including figurehead, leader, and liaison; informational, including monitor, disseminator, and spokesperson; and decision-making, including entrepreneur, disturbance handler, resource allocator, and negotiator. Case managers' tasks associated with each role are presented. Considering their work as managerial in nature will help case managers more effectively assist clients in goal achievement.

Health Resources↗
PubMed1993

Ultrastructural organization of type XI collagen in fetal bovine epiphyseal cartilage.

Type XI collagen was localized with polyclonal antibodies specific for alpha 1 (XI) and alpha 2 (XI) chains in the resting zone of epiphyseal cartilage from calf fetuses. The immunofluorescence technique was used on sections of cartilage, and the immunogold labelling technique for electron microscopy on fibrils isolated from cartilage and, for the first time, in situ on blocks of cartilage fractured in liquid nitrogen. Immunofluorescence showed that without pepsin treatment the staining of type XI collagen was restricted to the pericellular zones; after pepsin treatment, the staining was co-distributed with that of type II collagen. Immunoelectron microscopy performed on isolated fibrils and on cartilage blocks showed that after disruption of fibrils with pepsin, type XI collagen was labelled on small filaments on the fibrils. When the fibrils were not disrupted, labelling was observed in situ only at the ends of the fibrils or on cross-sections of some fibrils. These results indicate that type XI collagen is located inside type II collagen fibrils in fetal bovine epiphyseal cartilage, as already postulated for embryonic chicken sterna.

Animals↗
PubMed1993

The effects of PEG on second antibody immunoprecipitation and its use in immunoassay.

The effects of PEG on the second antibody immunoprecipitation have been studied in several radioimmunological systems. The following parameters have been studied in the assays: the average molecular weight and concentration of PEG, the species of the animal producing the first and second antibody, the nature of the antigen, the concentration of carrier immunoglobulins, and the rate of the immunoprecipitation. Thus, optimal conditions for the use of PEG with a second antibody have been defined in order to be used in any liquid phase immunoassay.

Animals↗
PubMed1993

Four markers of collagen metabolism as possible indicators of disease in the adult respiratory distress syndrome.

During the adult respiratory distress syndrome (ARDS), an irreversible fibrotic process can occur extremely rapidly. To establish indices of ARDS in pneumonia as well as the severity of the lung fibrosis, we have undertaken for the first time a study of four markers of collagen metabolism obtained from both bronchoalveolar lavage fluid (BALF) and serum: Type I (CI), Type III (CIII), N-terminal peptide of Type III procollagen (PIIINP), and galactosylhydroxylysylglucosyltransferase activity (GGT). We studied 61 patients (13 coma controls, 29 with pneumonia, and 19 with ARDS). In BALF, the average values of CI, CIII, PIIINP, and GGT were significantly higher in ARDS than in the control patients. The values for patients with pneumonia, although increased, were significantly lower than those in ARDS for CI, CIII, and PIIINP. In serum, the mean CI and PIIINP were significantly increased in pneumonia and ARDS, but the mean CIII was significantly increased only in ARDS compared with the control group. Significant positive linear correlations were observed for ARDS between CI and CIII or PIIINP and CIII in BALF and serum. Such correlations were observed for pneumonia only in serum. Molecular mass determinations demonstrated that CI- and CIII-related antigens in BALF were essentially intact triple helices of collagens or procollagens. Among patients with histologically defined interstitial fibrosis, the level of PIIINP in BALF was significantly higher for those with an additional intraalveolar fibrosis. In conclusion, measurements of these collagen markers may be useful for assessing disease activity and reflecting the flux of collagen molecules in the lung.

Adult↗
PubMed1993

Composition and organization of the collagen network produced by fetal bovine chondrocytes cultured at high density.

Fetal bovine chondrocytes isolated from the resting zone of epiphyseal cartilage were maintained in high-density culture for 4 weeks. From Day 2 in culture, the chondrocytes deposited an extracellular matrix composed of Types II, IX, and XI collagen. Types IX and XI collagen were restricted to the pericellular domain from Day 5. By 2 weeks the entire cell layer stained for antibodies to Type II and IX collagens. Type XI could be demonstrated throughout the cell layer by pepsinization of the sections. Results from both rotary shadowing and immunochemistry showed that the fibrils formed in culture were heterotypic, with Type IX collagen arranged along the surface and with Type XI collagen buried in Type II fibrils. Nonspecific Type VI collagen and the glycoproteins tenascin and fibrillin, previously described in cartilaginous tissue, were identified by their ultrastructural characteristics in the cell layer homogenate. Although the cells presented morphological characteristics of chondrocytes and still expressed cartilage-specific collagens, the appearance of Type I collagen in the culture cell layer after 4 weeks of culture demonstrates a partial dedifferentiation of the chondrocytes. The culture system described in this report provides an interesting tool for maintaining chondrocytes in a cartilage-like matrix to study the influence of different physical and chemical factors on the expression and differentiation of the cells.

Animals↗
PubMed1993

Inpatient and outpatient outcomes in Missouri's alcohol and drug treatment programs.

A comparison of the effectiveness of inpatient and outpatient services for alcohol and drug clients is presented. Controls for program completion and severity of substance use on entry to treatment are included. While inpatients do only as well as outpatients overall, inpatient services show significant advantage for particular classes of clients. Results, though preliminary, suggest that the recent call for a cutback in inpatient services is premature.

Alcoholism↗
PubMed1993

[Comparison of six potential serum markers of hepatic fibrosis in alcoholic disease of the liver].

The aim of this study was to compare 6 potential serum markers for hepatic fibrosis in patients with alcoholic liver disease. Ninety-three patients (50 +/- 11 years old, 62 males) with biopsy-proven alcoholic liver disease were included in the study. A liver biopsy and serum assays of type I, type III and type IV collagens, N-terminal peptide of type III procollagen, laminin (by radioimmunoassays) and apolipoprotein A1 (by nephelometry) were performed in all patients. A histological score of hepatic fibrosis was established. Alcoholic hepatitis lesions and perisinusoidal fibrosis were assessed separately. A significant correlation was found between the score of hepatic fibrosis and serum levels of type I collagen (r = 0.44, P < 10(-3)), type III collagen (r = 0.36, P < 10(-2)), N-terminal peptide of type III procollagen (r = 0.50, P < 10(-3)), type IV collagen (r = 0.44, P < 10(-3)), laminin (r = 0.50, P < 10(-3)), and apolipoprotein A1 (r = 0.21, P < 0.05). After adjustment for the presence of lesions of alcoholic hepatitis and perisinusoidal fibrosis (partial correlation), serum levels of type I collagen, type III collagen, N-terminal peptide of type III procollagen, type IV collagen, and laminin remained significantly correlated with the score of hepatic fibrosis; in contrast, correlation with serum apolipoprotein A1 was no longer significant. Serum levels of N-terminal peptide of type III procollagen, type IV collagen and laminin were significantly higher in patients with perisinusoidal fibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

The human rhabdomyosarcoma cell line A204 lays down a highly insoluble matrix composed mainly of alpha 1 type-XI and alpha 2 type-V collagen chains.

The biosynthesis of collagen by the A204 cell line was examined using polyclonal antibodies raised against collagen type V and type XI. The study of the pepsin-digested collagen showed that it is composed mainly of alpha 1(XI) and alpha 2(V) collagen chains in an apparent 2:1 ratio, suggesting the formation of heterotypic molecules [alpha 1(XI)]2 alpha 2(V). The existence of this chain stoichiometry was further demonstrated by immunoprecipitation of the molecule with an antibody recognizing alpha 2(V) but not alpha 1(XI) collagen chains. Electron microscopy analyses of 24-h cultures showed that this matrix is composed of thin fibrils, that can be decorated with immunogold-labelled anti-(type-V collagen) IgG, but not with anti-(type-XI collagen) IgG. The collagen matrix laid down by A204 cells is highly insoluble. In the presence of beta-aminopropionitrile, an inhibitor of lysyl oxidase, only a small proportion of intact collagen could be extracted without proteolytic treatment. Immunoblotting of intact medium collagen from cultures performed in the presence of beta-aminopropionitrile showed four distinct bands with each antibody. The migration of the bands, stained with anti-(type-V collagen) IgG, had apparent molecular masses of 127, 149, 161 and 198 kDa (compared to globular standards) while the bands stained with anti-(type-XI collagen) IgG had apparent masses of 145, 182, 207 and 225 kDa. These data indicate that type-V and type-XI collagen chains can assemble in heterotypic isoforms. In this system, the synthesized isoforms are able to aggregate into a highly cohesive matrix and they undergo a proteolytic processing closely similar to that of other fibrillar collagens.

Blotting, Western↗
PubMed1992

Immunoassay techniques for the detection of circulating antibodies to collagen following the use of collagen medical devices.

During the use of collagen medical devices, some adverse clinical reactions occur involving both the cellular and humoral types of the immune response. Thus, the development of immunoassay techniques for measuring the presence and the levels of circulating anticollagen antibodies is required. The authors present their protocol: it is a solid phase radioimmunoassay using collagen coated on polystyrene microplates and labelled protein A as the tracer. An example of the application of the technique is described. Anticollagen antibodies were monitored in 586 patients undergoing bovine collagen implant therapy. In a retrospective study on 166 patients we found a good correlation between the presence of antibodies to collagen and cellular immune reactions such as a positive skin test or adverse clinical reactions after implantation. A prospective study on 420 patients showed that the pretreatment anticollagen serologic test can be useful as an adjunct to skin testing in the conservative management of patients desiring bovine collagen implant therapy. The use of this double test allowed avoidance of any major clinical reaction and reduced minor signs of intolerance.

Adult↗