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J B Karlinsky

Publications and source records attributed to J B Karlinsky.

At least 19 recordsLinked to original sources
PubMed1998

cDNA cloning, genomic organization and chromosomal localization of human heparan glucosaminyl N-deacetylase/N-sulphotransferase-2.

The cDNA and gene encoding human heparan glucosaminyl N-deacetylase/N-sulphotransferase-2 have been cloned. The cDNA encoded a protein of 883 amino acids that was 94% similar to heparan N-sulphotransferase-2 from mouse mast cells. Comparison of the deduced amino acid sequences of human heparan N-sulphotransferase-1 and -2 showed that the enzymes were 70% similar; greater than 90% of the amino acids between residues 418 and 543 were identical. The least conserved amino acids were found in the N-terminus/putative transmembrane regions of the two enzymes. The human heparan N-sulphotransferase-2 gene was localized to chromosome arm 10q (band 10q22) by in situ fluorescent hybridization. The gene contains 13 exons spanning 6.5 kb, ranging in size from 88 bp (exon 2) to >1 kb (exon 1), and 12 introns, which were found to occur at similar sites within the coding sequence of the human heparan N-sulphotransferase-1 gene. The structure of the two genes differed in that the heparan N-sulphotransferase-1 gene contained one additional intron. The similarity of the heparan N-sulphotransferase-1 and -2 proteins and their similar exon-intron organization suggest that they derive from a common ancestral gene.

Amidohydrolases↗
PubMed1995

Molecular cloning of the human ryudocan promoter.

The promoter region of human ryudocan was isolated from a human lambda dash genomic library and cloned into pBluescript. The 5'flanking region contained a classical TATA box and GC rich regions that are commonly found in constitutively expressed genes. Two fusion gene constructs, one of 898 bp and the other of 480 bp of the 5' flanking DNA coupled to the luciferase gene, were transiently expressed in a mouse endothelioma cell line and in human umbilical endothelial cell cultures. Both constructs were capable of driving luciferase expression; the 898 bp construct produced greater levels of luciferase activity than the 480 bp construct in both cell types examined. Analysis of the sequence revealed the presence of several potential sites for nuclear transcription factor binding; the relevance of these sites is presently unknown.

Base Sequence↗
PubMed1992

Stress-strain characteristics of normal and emphysematous hamster lung strips.

A simple mathematical model of the one dimensional, stress-strain behavior of hamster lung tissue based on strain energy considerations was tested in degassed, uniaxially stretched strips obtained from normal and emphysematous hamster lungs cycled in saline. The relationship between Eulerian stress (sigma) and extension ratio (lambda) was found to take the form sigma = (lambda 2-1/lambda) x f(lambda) where the function f(lambda) was experimentally determined. Stress in six normal and five emphysematous strips was calculated by dividing the tension at each stretch increment by the strip cross-sectional area. Plotting sigma lambda/(lambda 2-1) versus a function of the form e eta lambda yielded a linear expression for f(lambda), me eta lambda + b, where n = 2. The complete stress-strain behavior of hamster lung strip tissue could then be expressed as a simple function of lambda over a range of lambda = 1.0-2.0: sigma = (lambda 2-1/lambda)(me2 lambda+b) The values of the constants m and b depend solely upon the mechanical properties of the elastic and collagen fiber networks in these atelectatic, saline cycled lung strips. The slope m = 0.151, and the intercept b = 0.416 in normal strips (r = 0.98). In emphysematous strips m = 0.016 and b = -0.199 (r = 0.82). Given the smaller m found for emphysematous strips, less strain energy accumulated with increasing stretch and did not even begin in these strips until lambda = 1.3. Further, the fit of the equation to the data was not as good for emphysematous as for normal strips. We conclude that the above equation adequately describes the stress-strain properties of normal hamster lung strips tissue but is not as good in emphysematous strips where the disease is patchy.

Animals↗
PubMed1992

Effects of hypoxia on heparan sulfate in bovine aortic and pulmonary artery endothelial cells.

Newly synthesized heparan sulfates purified from the cell layer of bovine aortic endothelial cells (BAECs) and main pulmonary artery endothelial cells (BPAECs) cultured under either normoxic (21% oxygen) or hypoxic (3% oxygen) conditions were characterized by size, charge, and capacity to bind to antithrombin III. Incorporation of radiolabeled sulfate into cell layer-associated heparan sulfate was reduced by 70% in BAECs and by 45% in BPAECs during exposure to 3% oxygen; degradation of radiolabeled heparan sulfate was not affected by hypoxia. However, the percentage of total radiolabeled heparan sulfate that bound to antithrombin III was increased by 33% for BAECs and by 120% for BPAECs when compared with radiolabeled heparan sulfate synthesized during the 21% oxygen exposure. Both the high- and low-antithrombin III affinity radiolabeled heparan sulfate consisted of two components of different sizes; the low-affinity components (mean sizes, 60 and 40 kd) generated under normoxic conditions were smaller than their respective high-affinity components (mean sizes, 70 and 55 kd) by molecular sieve chromatography. The components of low-antithrombin III affinity heparan sulfate generated during exposure to 3% oxygen were increased in size compared with the corresponding low-affinity components generated during the 21% oxygen exposure for both BPAECs and BAECs. In addition, the amount of the larger high-antithrombin III affinity component was reduced in both cell types exposed to hypoxia. There was no difference in functional heparin-like activity per dish between cells cultured at 3% and 21% oxygen; BAECs had twofold to threefold greater activity per dish than did BPAECs at both levels of oxygen.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Effects of intratracheal endotoxin administration on hamster lung glycosaminoglycans.

Incorporation of [3H]glucosamine and 35S into glycosaminoglycan (GAG) was measured in hamster lung explant cultures at 0, 1, 4, and 24 h after a single endotracheal instillation of Escherichia coli endotoxin. Lung content of GAG was measured in a second group of treated animals over an 8-day period. Albumin was detected after endotoxin treatment in bronchoalveolar lavage fluid at 24 h but was not found in lavage fluid 7 days later or in lavage fluid of saline-treated animals. Over the initial 24 h, increasing amounts of radiolabeled precursor molecules were incorporated into all classes of GAG. Proportionally more radiolabel was incorporated into hyaluronic acid and chondroitin sulfate, and less was incorporated into heparan sulfate. The proportion of radiolabel incorporated into dermatan sulfate did not change. Total lung content of hyaluronate and chondroitin sulfate was elevated at 24 h but was returning to baseline by 8 days. The lung content of dermatan sulfate was increased at 8 days; lung content of heparan sulfate did not change over the 8-day study period. Elevations in the amount of explant heparan sulfate that bound to antithrombin III (AT III) were found at 1 h after both saline and endotoxin treatment. Radiosulfated heparan sulfates were found in blood from hamsters treated with endotoxin 1 h previously; these heparan sulfates did not bind to AT III. However, blood contained heparin-like activity. We conclude that endotoxin differentially alters the metabolism of each class of hamster lung glycosaminoglycans and that metabolic changes begin very rapidly after endotoxin exposure. The relation of pulmonary endothelial injury to the presence of heparin-like activity in blood is not yet clear.

Animals↗
PubMed1990

Intrathoracic lymphadenopathy. A rare manifestation of rheumatoid pulmonary disease.

This is the first antemortem report of a patient with long-standing RA and interstitial lung disease who developed reactive mediastinal adenopathy coincident with increases in the activity of his interstitial process. Mediastinal adenopathy was discovered by means of CT of the chest as part of an evaluation of interstitial lung disease. The increasing use of better imaging techniques for this purpose will undoubtedly reveal more patients with this finding. Mediastinal lymphadenopathy complicating rheumatoid lung is clinically relevant; speculation is provided regarding the mechanism of the lymph node enlargement in this setting.

Aged↗
PubMed1989

Regulation of sulfated glycosaminoglycan production by prostaglandin E2 in cultured lung fibroblasts.

Prostaglandin E2 (PGE2) has been shown to increase the synthesis of hyaluronic acid in cultured fibroblasts by increasing the activity of hyaluronate synthetase, a group of plasma membrane-bound synthetic enzymes. We examined whether PGE2 also increased the activity of those enzyme systems involved in the synthesis of sulfated glycosaminoglycan in the human embryonic lung fibroblast. Exposure of cells to PGE2 resulted in dose-dependent increases in glucosamine incorporation into all sulfated glycosaminoglycan subtypes. PGE2 at 10(-7) mol/L increased total glycosaminoglycan per dish to 21.6 +/- 3.1 micrograms versus 12.0 +/- 2.5 micrograms in control untreated cultures. Stimulation of endogenous PGE2 production by bradykinin had a similar effect on glycosaminoglycan synthesis. To examine whether PGE2 affected sulfated glycosaminoglycan protein core production, cells were labeled with tritiated glucosamine in the presence of cycloheximide. Under these conditions, incorporation of radiolabel into all glycosaminoglycan subtypes was reduced. However, when exogenous sulfated glycosaminoglycan chain initiator (p-nitrophenyl beta-D-xyloside) was added, incorporation of tritiated glucosamine into sulfated glycosaminoglycan increased but not to levels found in control cultures. Application of PGE2 to cultures treated with cycloheximide alone, or to cultures treated with cycloheximide plus xyloside, increased tritiated glucosamine incorporation into chondroitin, dermatan sulfate, and to a lesser extent into heparan sulfate. We conclude that PGE2 stimulates synthesis of all sulfated glycosaminoglycan even in the absence of new protein core production, probably by increasing activities of sulfated glycosaminoglycan synthetase enzymes. PGE2 stimulation of heparan sulfate synthesis is partially dependent on the availability of heparan sulfate-specific protein core.

Bradykinin↗
PubMed1986

Lung mechanics and connective tissue levels in starvation-induced emphysema in hamsters.

The effect of starvation on lung mechanics, morphometry, and levels of connective tissue components was determined in young adult golden Syrian hamsters. A base-line control, fed control, and starved group were studied. Fed group animals increased body weight by 13%, but dry lung weight did not increase above that of the base-line controls. The total lung capacity when transpulmonary pressure was at 25 cmH2O (TLC25) also increased by 20% above base-line controls. The mean TLC25 of the starved group was greater than that of the base-line control group but less than that of the fed control group (P less than 0.05). Volume-corrected air-filled volume pressure (VP) curves of the three groups were similar. Volume-corrected saline-filled VP curves were identical in the three groups. Total lung collagen, elastin, glycosaminoglycan, and protein were similar in the three groups. Air space size was significantly increased and mean internal surface area was significantly decreased in the starved group compared with the base-line and fed controls. No evidence of alveolar wall destruction was evident by light or electron microscopy. We conclude that severe starvation of young adult hamsters produces air space enlargement without changes in lung elastic recoil. The mechanism of alveolar wall remodeling is not yet understood in this model of emphysema.

Air↗
PubMed1986

Bronchopulmonary lavage in pulmonary alveolar proteinosis: chest radiograph observations.

Ten therapeutic bronchopulmonary lavages were performed in four patients with pulmonary alveolar proteinosis. Chest radiographs taken during the lavage procedure showed increased density of the washed lung owing to the presence of instilled lavage saline. Radiographs obtained within the first hours after lavage showed a spectrum of change from minimal improvement to marked worsening compared with prelavage examinations. Subsequent radiographs over the next week showed gradual improvement in the treated lung. By 6 weeks there was moderate to marked improvement of chest radiographs compared with baseline in all cases.

Humans↗
PubMed1986

Young hamsters are more resistant than adults to endotracheally instilled porcine pancreatic elastase.

We measured the physiologic and stereologic response to 0.1, 0.2, and 0.4 microgram of porcine pancreatic elastase instilled in a volume of 0.25 ml 0.9% NaCl/100 g body weight into the trachea of groups of young and adult hamsters. The young hamsters averaged 50 g and the adult hamsters 116 g in initial body weight. Twenty-one days after administration of elastase, lung volumes, static lung compliance, maximum expiratory flow, the whole section mean linear intercepts (MLI) were measured. The degree of emphysema increased in all animals as a function of dose. Examination of the lung volume and compliance dose-response characteristics indicated that young hamsters developed less physiologic change with increasing elastase dose than did adult hamsters. Maximum expiratory flow and whole section MLI dose-response were similar in the young and adult elastase-treated groups. However, the MLI in young hamsters treated with the 0.4 microgram elastase dose was decreased in the outer third of the lung compared to adult emphysematous hamsters. Also, mean airspace density relative to saline control values in young hamsters was double that found in adult hamsters treated with the 0.4 microgram elastase dose. Although serum alpha 1-globulin levels were equivalent in both young and adult normal hamsters, values normalized for lung elastin content were significantly increased in young animals. We conclude that young hamsters show less change in lung function as a function of elastase dose twenty-one days after elastase instillation. Possible reasons for this include an increased ratio of lung alpha 1-globulin/lung elastin in young hamsters, their continued ability to grow new alveoli, and age related differences in airway size favoring a central distribution of enzyme.

Aging↗
PubMed1985

Thermoelastic properties of uniaxially deformed lung strips.

We examined the temperature dependence of small degassed hamster lung strip mechanics to develop insights into the molecular basis of lung elasticity. Quasi-static length-tension curves of adapted lung strips were generated at 10, 23, 37, 50, and 80 degrees C; quasi-static tension-temperature plots (QSTT) at strains of 0.5, 0.75, and 1.0 were then formulated. Static tension-temperature (STT) plots at strain 1 were independently generated from other strips. Stress relaxation was evaluated as a function of temperature at different strains; hysteresis ratio was calculated as a parameter of mechanical efficiency. Between 23 and 37 degrees C, the slopes of the QSTT plots at the different strains were close to zero. The slope of the STT plot was slightly positive, indicating that the tension developed by a stretched strip was primarily due to entropic changes with length, suggesting that strips behave like rubber polymers near physiological temperature. Between 10 and 23 degrees C, the slope of the QSTT curve was zero at the two lowest strains but was negative at strain 1; and slope of the STT curve was zero at strain 1. These data indicated that collagen fiber and possibly glycosaminoglycan function was abnormally affected at 10 degrees C. Between 50 and 80 degrees C at strain 1, the slopes of both the QSTT and STT plots at all strains were positive. These data suggested that elastic fiber function was altered between 50 and 80 degrees C such that both internal energetic and entropic contributions to the tension were changed. Stress relaxation and hysteresis data were consistent with these findings.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1982

Glycosaminoglycans in emphysematous and fibrotic hamster lungs.

Amounts and distributions of glycosaminoglycans were measured in lungs obtained from hamsters treated intratracheally 21 to 30 days previously with either saline, purified pancreatic elastase, or bleomycin. Normal hamster lungs contained 150 to 200 micrograms glycosaminoglycans per lung. Lungs made fibrotic by bleomycin contained significantly more glycosaminoglycans per lung than saline-treated control lungs; this increase was equally distributed among all glycosaminoglycan subtypes. Emphysematous lungs also contained more glycosaminoglycans than saline control lungs; this increase was less than that of fibrotic lungs and was limited to the dermatan sulfate subtype. The latter was increased in emphysematous lungs when expressed as a percentage of total glycosaminoglycans. In these hamster models of lung diseases that affect the connective tissue framework of the lungs, changes in lung glycosaminoglycans accompany changes in the other connective tissue components.

Animals↗
PubMed1980

Lung statics and connective tissues after penicillamine in bleomycin-treated hamsters.

Penicillamine was administered intraperitoneally to male golden hamsters for 30 days following a single intratracheal dose of bleomycin. Penicillamine treatment increased soluble collagen and decreased glycosaminoglycans in both normal and fibrotic lungs; total collagen and elastin were not significantly changed in normals but were lower in fibrotic animals. The proportions of the different glycosaminoglycans were not affected by penicillamine treatment. When related to body weight, the total lung capacity, vital capacity, and compliance both at low and high lung volumes were increased in animals that received only penicillamine when compared with animals that did not, but interpretation of these results is difficult because penicillamine-treated animals had low body weights. Lung statics were the same in animals that received penicillamine after bleomycin as in those that received bleomycin only, though penicillamine partially reversed the connective tissue expression of the bleomycin lung injury. We conclude that factors other than connective tissue levels are important in determining the mechanical behavior of fibrotic lungs.

Animals↗