Incorporation, distribution, and metabolism of polyunsaturated fatty acids in the pineal gland of rainbow trout (Oncorhynchus mykiss) in vitro.

The in vitro incorporation of 3H-radio-labeled arachidonic (20:4n-6) and docosahexaenoic (22:6n-3) acids by the photosensitive trout pineal gland was visualized using photon and electron microscopy. After 6 hr of incubation, 3H-20:4n-6 appeared distributed in photoreceptors, as well as in glial cells, whereas 3H-22:6n-3 was preferentially taken up by photoreceptors, mainly in the apical part (including the photoreceptive outer segment). Radioactivity was mainly seen over membranes of glia when the incorporation of 3H-20:4n-6 was followed by 12-18 hr of chase. We also report differences in the incorporation of 14C-radio-labeled linoleic (18:2n-6), linolenic (18:3n-3), eicosapentenoic (20:5n-3), 20:4n-6, and 22:6n-3 acids into the lipids in glands cultured under different lighting regimes. Phosphatidylcholine and triacylglycerols contained most of the radio-labeled polyunsaturated fatty acids (PUFA) incorporated. The proportion of incorporated 20:4n-6 recovered in phosphatidylinositol was always significantly higher than that found with the other PUFA. At least 10% of radioactivity from each incorporated substrate, except 22:6n-3, was recovered in elongation products. It is concluded that the pineal gland of the trout can assimilate exogenous PUFA into cellular lipids in vitro, in a manner consistent with our previous in vivo findings. In terms of lipid composition, the trout pineal gland resembles more the vertebrate retina than the rat pineal gland. This might be related to the loss of direct photosensitivity of the mammalian pineal. Together, the differences reported herein between 22:6n-3 and 20:4n-6 suggest the former plays an important role in the phototransduction process, whereas the latter might be more specifically involved in the production of phosphoinositide-derived second messengers.

Renal cell carcinoma in an intrathoracic kidney: radiographic findings and surgical considerations.

Ectopic intrathoracic kidney is a rare phenomenon and is usually an incidental finding on a chest radiograph. Of all intrathoracic kidneys, congenital ectopia is most often shown, with a traumatic etiology occurring much less frequently. We report a case of an ectopic intrathoracic kidney with associated renal cell carcinoma. Management, which was based on current treatment recommendations for isolated renal masses, consisted of radical nephrectomy. The patient has been without evidence of disease recurrence for 36 months after surgery.

Pentastomids and the tetrapod lung.

Pentastomids comprise a highly specialized taxon of arthropod-like parasites that probably became adapted to the lungs of amphibians and reptiles early in their long evolutionary history. Few other macroparasites exploit this particular niche. Pentastomids are often large, long-lived and yet they cause little observable pathology in lungs, despite being haematophagous. The lungs of all tetrapods are lined with pulmonary surfactant, a remarkable biological material consisting of a complex mixture of phospholipids, neutral lipids and proteins that has the unique ability to disperse over the air-liquid lining of the lung. In the lower tetrapods it acts as an anti-glue preventing adhesion of respiratory surfaces when lungs collapse during swallowing prey or upon expiration. In mammals, pulmonary surfactant also plays a critical role regulating the activity of alveolar macrophages, the predominant phagocytes of the lower airways and alveoli. This review outlines the evidence suggesting that lung-dwelling pentastomids, and also nymphs encysted in the tissues of mammalian intermediate hosts, evade immune surveillance and reduce inflammation by coating the chitinous cuticle with a their own stage-specific surfactant. The lipid composition of surfactant derived from lung instars of the pentastomid Porocephalus crotali cultured in vitro is very similar to that recovered from the lung of its snake host. Pentastomid surfactant, visualised as lamellate droplets within sub-parietal cells, is delivered to the cuticle via chitin-lined efferent ducts that erupt at a surface density of < 400 mm(-2). The fidelity of the system, which ensures that every part of the cuticle surface is membrane-coated, testifies to its strategic importance. Two other extensive glands discharge membrane-associated (hydrophobic?) proteins onto the hooks and head; some have been purified and partly characterized but their role in minimising inflammatory responses is, as yet, undetermined.

The effect of home training with direct blood pressure biofeedback of hypertensives: a placebo-controlled study.

BACKGROUND: Home training in self-lowering of blood pressure using continuous blood pressure feedback has not previously been reported. Enhancement of laboratory-learned skills was hypothesized on the basis of outcomes from other intellectual, emotional and physical endeavours. OBJECTIVE: To examine the supplementary effect of home blood pressure biofeedback training. DESIGN: Thirty unmedicated, mild hypertensives participated in a randomized, double-blinded, modified contingency placebo-controlled study. METHOD: After suitable screening and baseline blood pressure measurements subjects undertook eight laboratory biofeedback sessions and then 12 home training sessions over 4 weeks using continuous finger blood pressure monitoring. RESULTS: In the laboratory those being administered active therapy (n=16) lowered systolic pressures by 5 +/- 5.4 mmHg compared with a lowering of 4 +/- 4.2 mmHg with placebo (NS). During the fourth week at home lowering for the active group (11 +/- 8 mmHg) was greater than that with placebo (4 +/- 6.2 mmHg, P=0.017). Arm-cuff blood pressures were not statistically different for groups and with time but that of the active group was lower by 9 +/- 15.4/7 +/- 10.2 mmHg, which is a clinically relevant change, after home biofeedback. CONCLUSIONS: The efficacy of self-lowering of systolic blood pressure in mild hypertensives by continuous feedback was enhanced by 6 mmHg with 4 weeks of practice at home. Standard arm-cuff blood pressure was reduced by a clinically relevant amount. The home environment proved cost effective for this 'high-tech' approach.

Effects of docosahexaenoic (22:6n-3), tetracosapentaenoic (24:5n-3) and tetracosahexaenoic (24:6n-3) acids on the desaturation and elongation of n-3 polyunsaturated fatty acids in trout liver microsomes.

The effects of long chain n-3 polyunsaturated fatty acids (PUFA) on the desaturation and elongation systems involved in the conversion of 18:3n-3 to 24:6n-3 were investigated. Microsomes were prepared from the livers of rainbow trout and incubated with 14C-labelled 18:3n-3 and cofactors required for elongation and/or desaturation in the presence of 22:6n-3, 24:5n-3 or 24:6n-3. The formation of 24:6n-3 was significantly inhibited in the presence of 50 microM 22:6n-3, 24:5n-3 or 24:6n-3, whereas the amount of radiolabelled 20:5n-3 formed was inhibited by only 24:5n-3 or 24:6n-3 at the same concentration. When malonyl-CoA was omitted from the incubation system to allow the measurement of desaturation in the absence of elongation, the Delta6 desaturation of 14C-18:3n-3 to 14C-18:4n-3 was inhibited by approximately 25% in the presence of 24:5n-3 or 24:6n-3 but was not affected by 22:6n-3. The Delta5 desaturation of 14C-20:4n-3 was not affected by the presence of any of the long chain PUFA and no significant effect of 18:3n-3, 22:6n-3 or 24:6n-3 on the Delta6 desaturation of 24:5n-3 to 24:6n-3 was observed. To permit the measurement of individual elongation reactions, KCN was included in the incubation medium to inhibit desaturation and 14C-labelled 18:3n-3, 18:4n-3, 20:4n-3, 20:5n-3 and 22:5n-3 were examined as substrates. 18:4n-3 and 22:5n-3 were more extensively used for elongation than 18:3n-3, 20:4n-3 and 20:5n-3. The presence of 22:6n-3, 24:5n-3 or 24:6n-3 in the incubation system had no effect on any of the specific elongations of any of the substrates examined. It is concluded that, in the conversion of 18:3n-3 to 24:6n-3 by trout liver microsomes, the Delta6 desaturation of 18:3n-3 may be subjected to direct feedback inhibition and that 24:5n-3 may be preferred over 18:3n-3 as a substrate for Delta6 desaturation.

Effect of feedback signal and psychological characteristics on blood pressure self-manipulation capability.

Blood pressure presentation mode and personality are likely to influence biofeedback outcome. Thirty-six normotensive subjects were randomly assigned to visual or auditory continuous systolic feedback. "Distracting speech" and "broad band noise" were also superimposed and the effect on the biofeedback response was investigated. Psychological influence was also investigated. Systolic pressure reduction of 4 +/- 4.3 mmHg (visual, p = .04) and 5 +/- 5.5 mmHg (visual + auditory, p = .03) were achieved compared with auditory feedback (2 +/- 4.7 mmHg), which was less effective. The addition of noise or speech had no effect on the systolic response, but speech adversely affected diastolic reduction (p = .04). Mood (p = .003) was associated with systolic lowering, whereas increased trait anxiety (p = .06) and expectation (p = .03) had trends for opposite effects. Increased anger-hostility, state-anxiety, and expectation (p = .06) had links with systolic raising capability. We conclude that feedback modality and psychological characteristics have implications for studies investigating blood pressure manipulation capability.

Modification of odd-chain length unsaturated fatty acids by hepatocytes of rainbow trout (Oncorhynchus mykiss) fed diets containing fish oil or olive oil.

Hepatocytes isolated from rainbow trout fed on diets containing either fish oil or olive oil were incubated with individual odd-chain length unsaturated fatty acids (19:1n-9, 19:2n-6, 19:3n-3, 21:2n-6, 21:3n-6, 21:4n-6, 21:3n-3, and 21:5n-3) to examine whether these fatty acids were substrates for modification by desaturation and elongation. All odd-chain length fatty acids were readily assimilated into the lipids of hepatocytes from both dietary groups of fish, but their conversion to longer-chain, more unsaturated derivatives was more pronounced with cells from trout fed olive oil. Thus, the conversion of 19:2n-6 and 21:2n-6 to 21:3n-6 and 21:4n-6, and of 19:3n-3 to 21:4n-3 and 21:5n-3, was most obvious in cells from the olive oil group, as was the conversion of 21:3n-6 and 21:3n-3 to 21:4n-6 and 21:4n-3, respectively. Elongation of 19:1n-9 to 21:1n-9 and 23:1n-9 occurred in cells from both groups. No 23:6n-3 was detectable as a product of 19:3n-3 or 21:3n-3. However, this fatty acid was a major product formed by cells from fish fed olive oil presented with 21:5n-3. Cells from both groups of fish incorporated 21:4n-6 and 21:5n-3 into their lipids largely without modification but chain-shortened around 40, 23, and 19% of the incorporated 21:2n-6, 21:3n-3, and 19:1n-9, respectively. The results demonstrate that odd-chain length unsaturated fatty acids can act as substrates for the desaturation, elongation, and chain-shortening systems of trout hepatocytes.

Placebo-controlled biofeedback blood pressure effect in hypertensive humans.

The role of biofeedback in blood pressure control remains ill-defined because of nonspecific (placebo) effects, small study numbers, and the technical limitations of continuous pressure feedback. Clarification of its potential is awaited by those seeking a nonpharmacological approach to blood pressure control. This study examines the capability for systolic pressure lowering of 5 mm Hg or more using continuous pressure feedback in a statistical sample of untreated, well-characterized, mildly hypertensive individuals. Subjects were randomized in a double-blind study to active or placebo biofeedback. Placebo consisted of a modified contingency approach, using a partial disguise based on a digital high pass filter with 15 elements. Blood pressure-lowering capability was assessed during two laboratory sessions. Continuous visual feedback resulted in 11 of 28 subjects on active treatment and 12 of 28 on placebo treatment lowering their systolic pressure by 5 mm Hg or more (11 +/- 5.6 and 12 +/- 8.4 mm Hg, respectively; P = NS). Prestudy pressure was well-matched (153 +/- 9/97 +/- 4 and 154 +/- 8/98 +/- 4 mm Hg, respectively). An initial small difference in diurnal profile did not change. These findings indicate that among mildly hypertensive individuals, almost half can lower systolic pressure at will for short periods. This capability is independent of the real or placebo nature of the feedback signal. We conclude that there is no specific short-term biofeedback pressure-lowering capability in hypertensive individuals. Further exploration is needed to determine whether specific components of the placebo effect can be delineated, whether personality characteristics influence the response, and whether further biofeedback training can alter the outcome.

Biosynthesis of docosahexaenoic acid in trout hepatocytes proceeds via 24-carbon intermediates.

The role of 24:5n-3 and 24:6n-3 as intermediate in the formation of 22:6n-3 in trout liver was examined. Microsomes prepared from trout liver converted [1-14C]-eicosapentaenoic acid (20:5n-3) to 24: 5n-3 and 24:6n-3 but not docosahexaenoic acid (22:6n-3). The radiolabeled 24:5n-3 and 24:6n-3 were isolated from the microsomal incubations by argentation chromatography and used as substrates in incubations with hepatocytes isolated from trout liver. Both 14C-labelled 24:6n-3 and 22:6n-3-were produced by hepatocytes incubated with radiolabelled 24:5n-3. When hepatocytes were incubated with radiolabelled 24:6n-3, the amount of radioactivity recovered in 22:6n-3 over 6 hr increased in direct relation to the decrease observed in the amount of radioactivity recovered in 24:6n-3. The results suggest that the formation of 22:6n-3 in trout liver does not involve delta 4 desaturation of 22:5n-3 but rather proceeds via the delta 6 desaturation of 24:5n-3 with the subsequent chain shortening of the 24:6n-3 produced.

Prostate-specific antigen (PSA) and PSA density: racial differences in men without prostate cancer.

BACKGROUND: Many physicians now use serum prostate-specific antigen (PSA) to screen for prostate cancer in asymptomatic men. Whether or not a prostate biopsy should also be performed depends on an accurate definition of what constitutes a normal PSA value. Until recently, studies conducted to establish normal serum PSA values have involved study populations that have included few African-American men. PURPOSE: We sought to compare serum PSA levels and PSA density (i.e., serum PSA level/prostate volume ratio) in African-American and white men without histologic evidence of prostate cancer. METHODS: We reviewed the medical records of 826 consecutive men who underwent one or more prostate biopsies at the Veterans Affairs Medical Center in Shreveport, LA, from January 1993 through December 1995. In this retrospective review, we recorded patient's age, race, serum PSA level, digital rectal examination result, ultrasound-determined prostate volume, indications for biopsy, and biopsy results. Data from a total of 752 consecutive men who were either white or African-American and whose indication for biopsy included a serum PSA of greater than 4.0 ng/mL and/or an abnormal digital rectal examination were analyzed. To examine possible differences in serum PSA level, PSA density, prostate volume, and patient age, the two-sided Student's t test was employed. Multivariate linear regression analysis was used to determine if serum PSA levels were associated with the patient's age, race, or prostate volume in men without prostate cancer. RESULTS: Of the 752 men included in this analysis, 254 had histologic evidence of prostate cancer and 498 did not. Of the 498 men without prostate cancer, 367 (74%) men were white and 131 (26%) were black. There were no racial differences in age or calculated prostate volume. Serum PSA levels and calculated PSA density, however, were significantly (both P < .0001) higher in African-American men that in white men. A multivariate linear regression analysis indicated that race and prostate volume were independent variables associated with serum PSA level. For African-American and white men, serum PSA values of greater than 4 ng/mL were associated with prostate cancer with sensitivities of 89.5% and 81.9%, respectively, and specificities of 38.2% and 52.3%, respectively. CONCLUSION: Among biopsied men without histologic evidence of prostate cancer, African-Americans have a significantly higher PSA level and PSA density than similarly aged white men. IMPLICATIONS: Published criteria for normal PSA level and density have been derived primarily from white men and may not be directly applicable to other populations. Race-specific data are needed to fully optimize PSA as a tumor marker in racial populations that are at high risk for prostate cancer death.

The biosynthesis of docosahexaenoic acid [22:6(n-3)] from linolenic acid in primary hepatocytes isolated from wild northern pike.

Primary hepatocytes from wild northern pike Esox lucius were incubated with radiolabelled linolenic acid ([l-14 C]-18:3(n-3)) to assess their ability to synthesize docosahexaenoic acid [22:6(n-3)]. The distribution of radioactivity in lipid classes and hepatocyte polyunsaturated fatty acids (PUFA) was measured over the time-course of 24h. The majority of radioactivity from [l-14 C]-18:3(n-3) was recovered in hepatocyte triacylglycerols (TAG) and phosphatidylcholine (PC). The levels of radioactivity in TAG and in most of phospholipids, including PC, increased significantly over the incubation period. Radioactivity from [1-14 C]-18:3(n-3) was recovered in several hepatocyte PUFA, including 22:6(n-3), and the Δ6 and Δ5-desaturation products 18:4(n-3) and 20:5(n-3). The presence of radioactivity in C24 (n-3) PUFA may be evidence that the biosynthesis of 22:6(n-3) in pike proceeds via a pathway independent of Δ4-desaturation. Analysis by radio gas chromatography revealed that radiolabelled 24:6(n-3) was present among the desaturation and elongation products of [l-14 C]-18:3(n-3). The results establish that, under the in vitro conditions employed, pike hepatocytes are able to convert linolenic acid to 20:5(n-3) and 22:6(n-3).

Ultrasound diagnosis of filarial funiculoepididymitis.

Genital presentation of filarial disease is not uncommon in endemic areas of the world. Acute, febrile illness involving the epididymis and spermatic cord (funiculoepididymitis) is one of many such presentations. With an internationally mobile society, physicians today, even in nonendemic areas, may encounter patients with filarial infestations. We report the first case of presumptive diagnosis of this disease using scrotal ultrasound.

Polyunsaturated fatty acid composition of the salmon (Salmo salar L.) pineal organ: modification by diet and effect on prostaglandin production.

To examine the influence of dietary polyunsaturated fatty acids (PUFA) on the lipid composition of the pineal organ and its production of prostaglandins, Atlantic salmon were fed diets containing either fish oils rich in long-chain n-3 polyunsaturated fatty acids, or plant oils with high levels of 18:2(n-6) (sunflower oil) or 18:3(n-3) (linseed oil) for 12 weeks. Lipid content and lipid class composition of the pineal organ were not greatly influenced by the type of oil fed to the fish: choline phosphoglycerides were always the predominant lipid class and the proportion of polar lipids exceeded that of neutral lipids. The pattern of PUFA present in total lipid and individual lipid classes was, however, related to that of the dietary oil. The major PUFA in pineal total lipid from all four dietary groups was 22:6(n-3) and the proportion of n-6 PUFA present was highest in lipid from salmon fed sunflower oil. Both PGE and PGF analogues of the 2- and 3-series were detected in pineal homogenates from all dietary groups with the former prostaglandin being the most abundant. The ratio of PGE2/PGE3 was greatest in fish fed sunflower oil and lowest in those fed linseed oil. The results provide further evidence that despite its anatomical location the pineal organ resembles non-neural tissues more than brain in terms of lipid composition and prostaglandin production.

The desaturation and elongation of linolenic acid and eicosapentaenoic acid by hepatocytes and liver microsomes from rainbow trout (Oncorhynchus mykiss) fed diets containing fish oil or olive oil.

The products of desaturation and elongation of [1-14C]18:3(n - 3) and [1-14C]20:5(n - 3) were studied using hepatocytes and microsomes prepared from livers of trout maintained on diets containing either olive oil or fish oil, to establish the extent to which the formation of 22:6(n - 3) was enhanced in the absence of dietary 22:6(n - 3) and to investigate the pathway(s) of conversion of 18:3(n - 3) and 20:5(n - 3) to 22:6(n - 3). Levels of 20:5(n - 3) and 22:6(n - 3) in the total lipid of hepatocytes from trout fed olive oil were 20-fold and 10-fold, respectively, lower than in cells from trout fed fish oil. For both dietary groups, [1-14C]18:3(n - 3) was incorporated into hepatocyte lipid to a greater extent than [1-14C] 20:5(n - 3). Almost 70% of the total radioactivity from [1-14C]18:3(n - 3) was recovered in hepatocyte triacylglycerols, whereas radioactivity from [1-14C]20:5(n - 3) was recovered almost equally in neutral lipids (52%) and polar lipids (48%). The products of desaturation and elongation from both labelled substrates were esterified mainly into hepatocyte polar lipids, whereas elongation products of [1-14C]18:3(n - 3) were preferentially incorporated into neutral lipids. Radioactivity recovered in the 22:6(n - 3) of polar lipids of hepatocytes from trout fed olive oil, from both 14C substrates, was approximately double that in hepatocytes from trout fed fish oil. No radioactivity from either [1-14C]18:3(n - 3) or [1-14C]20:5(n - 3) was incorporated into 22:6(n - 3) by microsomes isolated from livers from either group of fish and incubated in the presence of acetyl-CoA, malonyl-CoA, NADH, NADPH, ATP and coenzyme A. However, significant radioactivity was recovered in 24:5(n - 3) and 24:6(n - 3) from [1-14C]20:5(n - 3) and more radioactive 24:6(n - 3) accumulated in microsomes from trout fed olive oil than from trout fed fish oil. The results establish that the formation of 22:6(n - 3) from both 18:3(n - 3) and 20:5(n - 3) in hepatocytes of rainbow trout is stimulated by omitting 22:6(n - 3) from the diet and are consistent with the biosynthesis of 22:6(n - 3) in trout liver cells proceeding via 24:5(n - 3) and 24:6(n - 3) intermediates.

Fatty acid metabolism in freshwater fish with particular reference to polyunsaturated fatty acids.

Fatty acids in fish can arise from two sources: synthesis de novo from non-lipid carbon sources within the animal, or directly from dietary lipid. Acetyl-CoA derived mainly from protein can be converted to saturated fatty acids via the combined action of acetyl-CoA carboxylase and fatty acid synthetase. The actual rate of fatty acid synthesis de novo is inversely related to the level of lipid in the diet. Freshwater fish can desaturate endogenously-synthesized fatty acids to monounsaturated fatty acids via a delta 9 desaturase but lack the necessary enzymes for complete de novo synthesis of polyunsaturated fatty acids which must therefore be obtained preformed from the diet. Most freshwater fish species can desaturate and elongate 18:2(n-6) and 18:3(n-3) to their C20 and C22 homologues but the pathways involved remain ill-defined. Cyclooxygenase and lipoxygenase enzymes can convert C20 polyunsaturated fatty acids to a variety of eicosanoid products. The dietary ratio of (n-3) to (n-6) polyunsaturated fatty acids influences the pattern of eicosanoids formed. The beta-oxidation of fatty acids can occur in both mitochondria and peroxisomes but mitochondrial beta-oxidation is quantitatively more important and can utilise a wide range of fatty acid substrates.

Physiological influences on continuous finger and simultaneous intra-arterial blood pressure.

Because of the clinical and experimental utility of continuous finger blood pressure measurements and the need for accuracy, we tested the performance of a new hydraulic device in 22 consecutive hypertensive subjects during physiological and pharmacological interventions. Ipsilateral brachial intra-arterial pressure was monitored during rest, Valsalva's maneuver, static handgrip, and mental arithmetic and after sublingual glyceryl trinitrate. In excess of 40,000 blood pressure values were analyzed. Average bias (intra-arterial minus finger blood pressure) was 8.2 +/- 17.0 mm Hg (mean +/- SD, P = NS) for systolic and 2.8 +/- 10.4 mm Hg (P = NS) for diastolic pressure. Two-way ANOVA of biases with subject and task factors showed a subject effect (P < .001). Intersubject and intrasubject standard deviations of bias were 13.8 and 9.8 mm Hg systolic and 8.7 and 5.7 diastolic, respectively. Linear drift (millimeters of mercury per minute) of finger pressure was greater (P < .001) for systolic than diastolic pressure during static exercise and math and after glyceryl trinitrate. Coefficients of determination for blood pressure ranged from 0.4 +/- 0.3 to 0.8 +/- 0.3 during the tasks. We conclude that (1) noninvasive finger blood pressure faithfully follows intra-arterial changes but with clinically relevant offsets, (2) this technique is best suited for assessing pressure changes, (3) physiological and pharmacological interventions do not consistently affect finger pressure accuracy, (4) many reports of finger blood pressure measuring devices are based on direct readings obtained with inadequate system response characteristics, and (5) the tested instrument falls short of the standard requirements (bias < or = 5 +/- 8 mm Hg) for devices that measure intermittently.

Characterization of proteoglycans produced by rat pleural mesothelial cells in vitro.

The mesothelial cell envelopes the surface of the parietal and visceral pleura. These cells are known to synthesize most of the protein constituents of the pleural basement membrane and interstitium. This study examined the ability of a rat pleural mesothelial cell line to synthesize proteoglycans in vitro. Cells were labeled with inorganic 35SO4 to label the glycosaminoglycan moiety of proteoglycans. The medium and combined cell membrane/extracellular matrix fractions contained 73 and 25% of the proteoglycan radioactivity, respectively. The medium contained a single chondroitin/dermatan sulfate proteoglycan of approximately 190 kDa, consistent with biglycan. As determined by Northern analysis of steady-state levels of messenger RNA, the cells contained message for biglycan. Stimulation of the cells with epidermal growth factor resulted in the appearance of a second chondroitin/dermatan sulfate proteoglycan of approximately 97 kDa, characteristic of decorin. The cell membrane/matrix contained a biglycan-like chondroitin/dermatan proteoglycan and several heparan sulfate proteoglycans. Pleural mesothelial cells in vitro are capable of synthesizing a variety of interstitial and basement membrane proteoglycans.