Survey of echinococcosis in Hokkaido and measure against it

Exposure to hyperoxia results in lung injury and a decrease in lung collagen. Retinol is known to influence collagen gene expression, and retinol deficiency has been shown to potentiate hyperoxic lung injury. To investigate the combined effects of retinol deficiency and hyperoxia on lung collagen expression, retinol-deficient rats were exposed to acute hyperoxia, and expression of the alpha-1 chains of type I procollagen [pro alpha 1 (I)] and type III procollagen [pro alpha 1 (III)] were determined using Northern hybridization analyses and immunohistochemical staining. Hyperoxia alone reduced pro alpha 1 (I) mRNA by 60 +/- 4% (p < .05) and pro alpha 1 (III) mRNA by 30 +/- 5% (p < .05), and retinol deficiency alone reduced pro alpha 1 (I) mRNA abundance by 49 +/- 8.8% (p < .05) and pro alpha 1 (III) mRNA abundance by 14 +/- 7.5% (p = not significant), respectively. Retinol deficiency plus hyperoxia did not cause any further reduction in procollagen mRNA than that seen with oxygen exposure alone. Immunohistochemical staining demonstrated decreased staining for type I collagen in retinol-deficient animals. Hyperoxic exposure resulted in decreased connective tissue staining and increased alveolar wall staining for type I collagen. Retinol deficiency and hyperoxia together resulted in a marked increase in alveolar exudates staining for type I collagen. No changes in type III collagen staining were seen. These findings demonstrate that while retinol deficiency does not potentiate hyperoxia-induced reductions in procollagen mRNA, it is associated with alterations in collagen staining in distal lung and immunohistologic evidence of collagen fragments in alveolar exudates.     

Dopamine restores lung ability to clear edema in rats exposed to hyperoxia

Exposure to hyperoxia causes lung injury, decreases active sodium transport and lung edema clearance in rats. Dopamine (DA) increases lung edema clearance by stimulating vectorial Na+ flux and Na, K-ATPase function in rat alveolar epithelium. This study was designed to test whether DA (10(-)5 M) would increase lung edema clearance in rats exposed to 100% O2 for 64 h. Active Na+ transport and lung edema clearance decreased by approximately 44% in rats exposed to acute hyperoxia (p < 0.001). DA increased lung edema clearance in room air breathing rats (from 0.50 +/- 0.02 to 0.75 +/- 0.06 ml/h) and in rats exposed to 100% O2 (from 0.28 +/- 0.03 to 0. 67 +/- 0.03 ml/h). Disruption of cell microtubular transport system by colchicine blocked the stimulatory effect of DA on active Na+ transport in control and hyperoxic rats, whereas the isomer beta-lumicolchicine, which does not affect cell microtubular transport, did not inhibit the stimulatory effects of dopamine. The Na,K-ATPase alpha1-subunit protein abundance increased in the basolateral membranes of alveolar type II (ATII) cells incubated with 10(-)5 M DA for 15 min, probably by recruiting Na+ pumps from intracellular pools. Colchicine, but not beta-lumicolchicine, prevented the recruitment of alpha1 subunits to the plasma membrane by DA. Accordingly, DA restored lung ability to clear edema in hyperoxic-injured rat lungs. Conceivably, dopamine induces recruitment of Na+ pumps from intracellular pools to the plasma membrane of alveolar epithelial cells and thus increases lung edema clearance.     

Insulin promotes phosphorylation and activation of geranylgeranyltransferase II. Studies with geranylgeranylation of rab-3 and rab-4

Rab proteins play a crucial role in the trafficking of intracellular vesicles. Rab proteins are GTPases that cycle between an inactive GDP-bound form and an active GTP-bound conformation. A prerequisite to Rab activation by GTP loading is its post-translational modification by the addition of geranylgeranyl moieties to highly conserved C-terminal cysteine residues. We examined the effect of insulin on the activity of geranylgeranyltransferase II (GGTase II) in 3T3-L1 fibroblasts and adipocytes. In fibroblasts, insulin increased the enzymatic activity of GGTase II 2.5-fold after 1 h of incubation, an effect that is blocked by perillyl alcohol, an inhibitor of prenyltransferases, but not by the geranylgeranyltransferase I inhibitor, GGTI-298, or the farnesyltransferase inhibitor, alpha-hydroxyfarnesylphosphonic acid. Concomitantly, insulin stimulated the phosphorylation of the GGTase II alpha-subunit without any effect on the GGTase II beta-subunit. At the same time, insulin also increased the amounts of geranylgeranylated Rab-3 in 3T3-L1 fibroblasts from 44 +/- 1.2% in control cells to 63 +/- 3.8 and 64 +/- 6.1% after 1 and 24 h of incubation, respectively. In adipocytes, insulin increased the amounts of geranylgeranylated Rab-4 from 38 +/- 0.6% in control cells to 56 +/- 1.7 and 60 +/- 2.6% after 1 and 24 h of incubation, respectively. In both fibroblasts and adipocytes, the presence of perillyl alcohol blocked the ability of insulin to increase geranylgeranylation of Rab-4, whereas GGTI-298 and alpha-hydroxyfarnesylphosphonic acid were without effect, indicating that insulin activates GGTase II. In summary, insulin promotes phosphorylation and activation of GGTase II in both 3T3 L1 fibroblasts and adipocytes and increases the amounts of geranylgeranylated Rab-3 and Rab-4 proteins.     

Hypoxia regulates basal and induced DNA synthesis and collagen type I production in human cardiac fibroblasts: effects of transforming growth factor-beta1, thyroid hormone, angiotensin II and basic fibroblast growth factor

Analysis of post-infarct ventricular remodeling consistently shows the accumulation of collagen in failing heart. The goal of this study was to gain insights into the underlying mechanisms of this event. We determined the effect of hypoxia, caused as the result of ischemia, on biological responses including cell viability, basal and growth factor-stimulated proliferative capacity and collagen type I production in cardiac fibroblasts obtained from adult human heart. The cell viability, as examined by light microscopy and analysis of DNA, did not change by hypoxia (2% oxygen). Basal level of protein synthesis, as determined by measuring the incorporation of 3H-leucine, decreased (30%, P<0.05) under hypoxia. Transforming growth factor-beta (TGF-beta1)- and thyroid hormone (T3)-induced increases in protein synthesis did not change under hypoxia. In contrast, basic fibroblast growth factor (bFGF)-stimulated protein synthesis enhanced significantly under hypoxia. Angiotensin II (Ang II)-treatment, which did not induce significant changes in protein synthesis under ambient conditions, led to moderate but significant increase under hypoxia. Basal level of DNA synthesis, as determined by measuring the incorporation of 3H-thymidine into DNA, decreased (32%, P<0.05) under hypoxia. The TGF-beta1-induced inhibition of DNA synthesis which was observed under ambient conditions was reversed [61% (P<0.005) increase under hypoxia]. Under ambient conditions, T3, Ang II and bFGF stimulated DNA synthesis and their effects were enhanced under hypoxia. Northern analysis showed a 46% (P<0.05) increase in the level of pro alpha1(l) collagen mRNA under hypoxia. The TGF-beta1-induced increase in the level of pro alpha1(l) collagen mRNA, under ambient conditions, was not observed under hypoxia. On the other hand, the T3-induced decrease in pro alpha1(l) collagen mRNA was reversed under hypoxia. Ang II- and bFGF-treatment of human cardiac fibroblasts did not cause detectable changes in the level of pro alpha1(l) collagen mRNA under ambient conditions or hypoxia. At the protein level, the amount of immunoreactive collagen type I, as determined by immunoslot blot analysis, was increased (33%, P<0.05) under hypoxia. Treatment of human cardiac fibroblasts with TGF-beta1 and T3 under ambient conditions led to diminished level of collagen type I. Under hypoxia, however, effect of both factors was reversed. The level of immunoreactive collagen type I in Ang II- and bFGF-treated cells, which was comparable to that in untreated cells under ambient conditions, remained unchanged under hypoxia. Together, these results provide evidence that hypoxia regulates growth, proliferative capacity and collagen type I production in human cardiac fibroblasts, and that although hypoxia alone may not be a stimulus for human cardiac fibroblast proliferation, it enhances growth factor-induced DNA synthesis in those cells. Furthermore, hypoxia by increasing the basal levels of collagen type I and by reversing the TGF-beta1- and T3-induced inhibition of collagen type I gene expression in human cardiac fibroblasts can enhance overall collagen type I production. Combinatorial effects of hypoxia on proliferation and collagen type I production in cardiac fibroblasts contribute to the post-infarct remodeling of the collagen matrix in failing human heart.     

Conserved features of TBE1 transposons in ciliated protozoa

BACKGROUND: Accessory function (AF) is one way antigen presenting cells generate sufficient secondary signals for optimal T-cell proliferation and IL-2 production. In general, alveolar macrophages (AM) are inferior accessory cells in comparison to monocytes whereas in sarcoidosis AF of AM is increased. METHODS: We compared the accessory index (AI) of AM and peripheral blood monocytes (PBM) of 41 patients with inactive sarcoidosis (SAR I, n = 12); active sarcoidosis with new or progressing symptoms (SAR II, n = 19), active sarcoidosis with spontaneous remission (SAR III, n = 10), tuberculosis (TB, n = 12), hypersensitivity pneumonitis (HP, n = 12), Wegener's disease (WD, n = 2), undefined alveolitis (UA, n = 8) and chronic obstructive pulmonary disease (COPD, n = 6) by employing the histoincompatibility-insensitive Jurkat cells as indicator cells. RESULTS: Compared with the controls (1.08 +/- 0.3) AMs of all groups but SAR I (AI: 0.96 +/- 0.42) exhibited significantly increased AIs (SAR II: 3.6 +/- 3.9; SAR III: 3.2 +/- 2.4; TB: 2.8 +/- 2.2; HP: 3 +/- 2; UA: 2.7 +/- 2.3; COPD: 3.1 +/- 2.2; p < 0.05 for all comparisons). Only in HP, AI of PBM was significantly increased compared with controls (3 +/- 1.5, 1.3 +/- 0.5, respectively; p < 0.001). Alveolar macrophages from patients with arcoidosis, TB, and HB express the costimulatory molecule CD80 on their surface and anti-CD80 antibodies inhibited the IL-2 release of Jurkat cells in this system to 59 +/- 27%. CONCLUSIONS: Our data demonstrate that AM from patients with various diseases have the capability to act as competent accessory cells and that the reported accessory function of these cells is at least in part mediated by the expression of CD80.     

Comparison of metoprolol and carvedilol pharmacology and cardioprotection in rabbit ischemia and reperfusion model

Carvedilol, a selective alpha1 and non-selective beta-adrenoceptor antagonist and antioxidant, has been shown to provide significant cardiac protection in animal models of myocardial ischemia. To further explore the mechanisms contributing to carvedilol cardioprotection efficacy, the effects of carvedilol on hemodynamic variables, infarct size and myeloperoxidase activity (an index of neutrophil accumulation) were compared with a beta1-selective adrenoceptor antagonist, metoprolol. Carvedilol (1 mg/kg) or metoprolol (1 mg/kg or 1 mg/kg + 0.5 mg/kg 90 min later) was given intravenously 5 min before reperfusion. In vehicle-treated rabbits, ischemia (60 min) and reperfusion (180 min) resulted in significant increments in left ventricular end diastolic pressure, large infarcts (59+/-2.6% of area-at-risk) and marked increase in myeloperoxidase activity (0.59+/-0.09 U/100 mg tissue). Carvedilol treatment resulted in sustained reduction of pressure-rate-index and significantly smaller infarcts (22.0+/-2.5%, P < 0.01 vs. vehicle) as well as decreased myeloperoxidase activity (0.186+/-0.056 U/100 mg tissue, P < 0.01 vs. vehicle). The highest dose of metoprolol, 1 mg/kg + 0.5 mg/kg, that resulted in pressure-rate-index comparable to that of 1.0 mg/kg carvedilol, failed to reduce myeloperoxidase activity in the ischemic myocardial tissue, and the infarct size (35+/-3.1%) was significantly larger than in carvedilol-treated animals. Taken together, this study suggests that the superior cardioprotection of carvedilol over metoprolol is not a consequence of hemodynamic variances but possibly the result of the additional pharmacological properties of carvedilol such as the antioxidant and anti-neutrophil effects.     

Tumor necrosis factor soluble receptor 75: the principal receptor form released by human alveolar macrophages and monocytes in the presence of interferon gamma

Tumor necrosis factor alpha(TNF alpha), a proinflammatory cytokine secreted predominantly by monocytemacrophages, interacts with two cell-surface receptors: TNF-R55 and TNF-R75. Few studies have been devoted to their modulation on human alveolar macrophages (AM). Both source and target of TNF(alpha), AM also release its inhibitors, the soluble receptors, following the cleavage of the extracellular domain of TNF-R55 and TNF-R75. Because in vivo AM are subject to activation by exogenous or endogenous stimuli, we analyzed the release of both receptors into the cell culture supernatant in response to lipopolysaccharide (LPS), phorbol myristate acetate (PMA), and cytokines such as interleukin 2(IL-2), IL-4, IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), and interferon gamma (IFN-gamma). Results were compared with those obtained on peripheral blood monocytes (Mo), and the role of receptor recycling was investigated using inhibitors such as monensin and chloroquine. In our culture conditions, basal release by unstimulated AM amounted to 0.3 +/- 0.1 and 0.5 +/- 0.1 ng/ml for TNF-sR55 and TNF-sR75, respectively. In the same conditions, Mo released 1.2 +/- 1.2 ng/ml of TNF-sR55 and 5.1 +/- 0.1 ng/ml of TNF-sR75. PMA slightly increased mRNA expression and release of TNF-sR55, but those of TNF-sR75 were enhanced approximately 4-fold. After 24 h of culture, the release of TNF-sR75 was 2.5-fold higher on Mo than on AM. Of the cytokines tested on AM, IFN-gamma increased the release of TNF-sR75 3-fold, but that of TNF-sR55 only between 1.5- and 2-fold. GM-CSF enhanced them to a lower extent (approximately 1.5-fold). Shedding occurred despite the presence of chloroquine, monensin and colchicine, suggesting that cleavage takes place on the cell surface rather than after internalization. Addition of colchicine increased the release of TNF-sR75 induced by LPS and IFN-gamma, but not by PMA. In conclusion, Mo and AM differ in their ability to release TNF(alpha) and TNF-sR. On AM the release of each receptor appears to be regulated separately. Finally, IFN-gamma was among the most efficacious cytokines to induce the release of both receptors, with TNF-sR75 being more liable to shedding. Thus, the two TNF-R seem to be ruled by separate mechanisms and to differ in terms of release sensitivity.     

Quantitation of the alveolar distribution of surfactant mixtures in normal and injured lungs

The uptake and distribution of two surfactant mixtures, Exosurf and Infasurf, instilled into the lungs of normal and hyperoxia-exposed (100% O2, 60 h) rabbits, were quantified at the alveolar level using flow cytometry and fluorescence microscopy. The surfactants were labeled with the fluorescent phospholipid analog NBD-C12-PC (1-palmitoyl-2-[12-[(7-nitro-2-1, 3-benzoxadiazol-4-yl)amino]dodecanoyl]-sn-glycero-3-phosphocholine ) in 100:1 molar ratio. Rabbits were killed 2 h after the instillation of either surfactant (80 mg phospholipid [PL]/kg), and alveolar macrophages (AM) and alveolar type II (ATII) cells were isolated and examined for the presence of NBD fluorescence. The fractions of cells, with NBD fluorescence values higher than autofluorescence, isolated from the lungs of air-breathing rabbits instilled with either Infasurf or Exosurf, were 84% and 63% for AM, and 55% and 45% for ATII cells. Exposure of rabbits to hyperoxia decreased the fraction of NBD-positive AM following Infasurf instillation, and the mean increase in NBD-associated fluorescence in ATII cells following Exosurf instillation. Our results suggest that sublethal hyperoxia decreases the short-term uptake but not the distribution of intratracheally instilled Exosurf.     

Preparation and activity of complexes of transition metals and thiolic heterocyclic ligands

The activities of cell-associated IL-1 (IL-1 alpha) and extracellular IL-1 (IL-1 beta) in alveolar macrophages (AM) from rats with bleomycin-induced pulmonary fibrolosis were measured to determine their role in fibroblast growth. AM were obtained on Days 1, 3, 6, 9 and 12 after a intratracheal injection of bleomycin, and the IL-1 activity and fibroblast growth-stimulating activity in fixed AM and AM supernatants were measured. Higher cell-associated IL-1 activity was detected in AM from bleomycin-treated rats than in those of control on Day 1 through 9. But extracellular IL-1 activity in the supernatant of AM from bleomycin-treated rats significantly higher only on Day 1. Expression of IL-1 alpha mRNA in AM from bleomycin-treated rats was significantly higher than that in AM of control, but there was no significant difference in the mRNA levels of IL-1 beta in AM of these two groups. Fixed AM from bleomycin-treated rats caused growth-inhibition of fibroblasts in a density-dependent manner. The inhibitory activity was decreased by pretreatment of fixed AM with anti IL-1 alpha antibody, but not anti IL-1 beta antibody. These results suggest that cell-associated IL-1 (IL-1 alpha) is produced continuously in AM from rats with bleomycin-induced pulmonary fibrosis and may be important in regulation of this disorder by inhibiting fibroblast growth.     

The prognosis of surgery on the elderly. Proposal for a parametric evaluation

The effect of lipophilicity on the absorption of peptides from the lungs was investigated. D-phenylalanine (F)-glycine (G) hexapeptides were synthesised to differ, predominantly, only in their lipophilicity. Rat alveolar type II cells were isolated and cultured on plastic, or polycarbonate filters; by day 6 they had de-differentiated to an alveolar type I-like epithelium. The permeability of the monolayers to the hexapeptides was determined. The hexapeptides were metabolically and chemically stable for greater than 24h in the presence of the cells. They did not adhere to the cell culture plastic and were associated only to a low extent with the cell monolayer. The apical to basolateral permeability coefficients for D-F1G5, D-F2G4, and D-F3G3 were 2.19+/-0.53, 1.75+/-0.42 and 2.20+/-0.56 x 10(-7) cm s(-1) respectively. The permeability of the monolayers to D-F1G5 and D-F2G4 was concentration and direction independent, however for D-F3G3 the monolayer was more permeable in the basolateral to apical direction. There was no correlation between the lipophilicity of the hexapeptides and permeability coefficients: other physicochemical parameters did not predict hexapeptide transport. Lipophilicity does not appear to control the transport of hexapeptides across the alveolar epithelium probably as a consequence of the peptides being transported via the paracellular route.     

Mycobacterium tuberculosis invades and replicates within type II alveolar cells

Although Mycobacterium tuberculosis is assumed to infect primarily alveolar macrophages after being aspirated into the lung in aerosol form, it is plausible to hypothesize that M. tuberculosis can come in contact with alveolar epithelial cells upon arrival into the alveolar space. Therefore, as a first step toward investigation of the interaction between M. tuberculosis and alveolar epithelial cells, we examined the ability of M. tuberculosis to bind to and invade alveolar epithelial cells in vitro. The H37Rv and H37Ra strains of M. tuberculosis were cultured to mid-log phase and used in both adherence and invasion assays. The A549 human type II alveolar cell line was cultured to confluence in RPMI 1640 supplemented with 5% fetal bovine serum, L-glutamine, and nonessential amino acids. H37Rv was more efficient in entering A549 cells than H37Ra, Mycobacterium avium, and Escherichia coli Hb101, and nonpiliated strain (4.7% +/- 1.0% of the initial inoculum in 2 h compared with 3.1% +/- 0.8%, 2.1% +/- 0.9%, and 0.03% +/- 0.0%, respectively). The invasion was more efficient at 37 degrees C than 30 degrees C (4.7% +/- 1.0% compared with 2.3% +/- 0.8%). H37Rv and H37Ra were both capable of multiplying intracellularly at a similar ration over 4 days. Binding was inhibited up to 55.7% by anti-CD51 antibody (antivitronectin receptor), up to 55% with anti-CD29 antibody (beta(1) integrin), and 79% with both antibodies used together. Update of M. tuberculosis H37Rv was microtubule and microfilament dependent. It was inhibited by 6l.4% in the presence of 10 micron colchicine and by 72.3% in the presence of 3 micron cytochalasin D, suggesting two separate pathways for uptake. Our results show that M. tuberculosis is capable of invading type II alveolar epithelial cells and raise the possibility that invasion of alveolar epithelial cells is associated with the pathogenesis of lung infection.     

Effects of tumor necrosis factor-alpha on glucose metabolism in cultured human muscle cells from nondiabetic and type 2 diabetic subjects

The effects of tumor necrosis factor-alpha (TNF alpha) on glucose uptake and glycogen synthase (GS) activity were studied in human skeletal muscle cell cultures from nondiabetic and type 2 diabetic subjects. In nondiabetic muscle cells, acute (90-min) exposure to TNF alpha (5 ng/ml) stimulated glucose uptake (73 +/- 14% increase) to a greater extent than insulin (37 +/- 4%; P < 0.02). The acute uptake response to TNF alpha in diabetic cells (51 +/- 6% increase) was also greater than that to insulin (31 +/- 3%; P < 0.05). Prolonged (24-h) exposure of nondiabetic muscle cells to TNF alpha resulted in a further stimulation of uptake (152 +/- 31%; P < 0.05), whereas the increase in cells from type 2 diabetics was not significant compared with that in cells receiving acute treatment. After TNF alpha treatment, the level of glucose transporter-1 protein was elevated in nondiabetic (4.6-fold increase) and type 2 (1.7-fold) cells. Acute TNF alpha treatment had no effect on the fractional velocity of GS in either nondiabetic or type 2 cells. Prolonged exposure reduced the GS fractional velocity in both nondiabetic and diabetic cells. In summary, both acute and prolonged treatment with TNF alpha up-regulate glucose uptake activity in cultured human muscle cells, but reduce GS activity. Increased skeletal muscle glucose uptake in conditions of TNF alpha excess may serve as a compensatory mechanism in the insulin resistance of type 2 diabetes.     

Ventilator-associated lung injury decreases lung ability to clear edema in rats

Ventilator-associated lung injury (VALI) is caused by high tidal volume (VT) excursions producing microvascular leakage and pulmonary edema. However, the effects of VALI on lung edema clearance and alveolar epithelial cells' Na,K-ATPase function have not been elucidated. We studied lung edema clearance in the isolated-perfused rat lung model after ventilation for 25, 40, and 60 min with high VT (peak airway opening pressure [Pao] of approximately 35 cm H2O) and compared them with low VT ventilation (Pao approximately 8 cm H2O), moderate VT ventilation (Pao approximately 20 cm H2O), and nonventilated rats. Lung edema clearance in control rats was 0.50 +/- 0.02 ml/h and decreased after 40 and 60 min of high VT to 0.26 +/- 0.03 and 0.11 +/- 0.08 ml/h, respectively (p < 0.01), but did not change after low VT and moderate VT ventilation at any time point. Lung permeability to small (22Na+, [3H]mannitol) and large solutes (fluorescein isothiocyanate-tagged albumin [FITC-albumin]) increased significantly in rats ventilated for 60 min with high VT, compared with low VT, moderate VT, and control rats (p < 0.01). Paralleling the impairment in lung edema clearance we found a decrease in Na,K-ATPase activity in alveolar type II (ATII) cells isolated from rats ventilated with moderate VT and high VT for 40 min without changes in alpha1 Na,K-ATPase mRNA. We reason that VALI decreases lung ability to clear edema by inhibiting active sodium transport and Na,K-ATPase function in the alveolar epithelium.     

Type II alveolar epithelial cells and free alveolar cells after intratumor TNF-alpha administration

The experiment used Morris hepatoma 5123 series growing in muscles of the Buffalo rats. A suspension of 3 x 10(6) neoplastic cells was injected into the right hind leg of the animals. After fourteen days, TNF-alpha was administered into the tumour in a dose of 1.5 x 10(4) U/24 hours in 0.5 ml PBS solution. The group I animals were injected for 4 days and group II for 8 days. Control groups consisted of rats with injected Morris hepatoma which were given PBS solution instead of TNF-alpha (group III A and B) and animals without the hepatoma, given 4 or 8 TNF-alpha, respectively (groups IV A and B). In the present study, we have explored the effect of intratumor TNF-alpha administration on the composition of cells isolated from the lungs through multiple bronchoalveolar lavages (BAL). Ultrastructural evaluation of the pulmonary tissue was done using a transmission electron microscope (TEM), with special attention paid to type II alveolar epithelial cells and free alveolar cells. Examinations in TEM in groups I, II and IV (A and B) found, in the lumen of alveoli, an increase in the number of alveolar macrophages (AM) with morphological features of intensified activity and AM with numerous secondary lysosomes containing material of phospholipid structure. Also, numerous type II alveolar epithelial cells with emptied lamellar bodies were observed. The above mentioned changes were especially marked after eightfold TNF-alpha administration. In groups I, II and IV (A and B), compared with group III, a significant increase was found in the total number of cells isolated by BAL as well as in the number of cells with positive reaction in staining according to Beckstead's method. It may indicate that the changes in the parameters mentioned above are related to TNF-alpha action. The results obtained indicate the possibility of systemic effect of TNF-alpha after its administration into the experimental Morris hepatoma.     

Vitamin D3 inhibits proliferation and increases c-myc expression in fibroblasts from psoriatic patients

Fibroblast cultures were established from the skin of normal and psoriatic subjects. The response to 1 alpha,25-dihydroxyvitamin D3 [1,25-(OH)2D3] of each kind of cells was assessed by measuring tritiated thymidine incorporation into DNA as an index of cell proliferation. We found that both types of cells responded with a similar dose- and time-dependent inhibition of thymidine incorporation. We also studied the response of the mRNA encoding the proto-oncogene c-myc, since its level is associated to the proliferative state in many cell types. Psoriatic fibroblasts contained higher basal amounts of c-myc RNA than control fibroblasts. Addition of 1,25-(OH)2D3 to the culture medium induced a time-dependent increase of c-myc RNA in psoriatic fibroblasts but not in controls. As a control, retinoic acid had no effect in any of the two cell types. It is concluded that in primary normal human fibroblasts, c-myc RNA levels are not correlated with the proliferative state, and that there is an altered expression of this proto-oncogene in psoriasis.     

The role of neutrophils in the pathogenesis of idiopathic pulmonary fibrosis

STUDY OBJECTIVES: The prognostic value of the neutrophil count in BAL fluid (BALF) has been controversial. The role of neutrophils in this inflammatory lung disease, therefore, was evaluated in this study by additional measures. MATERIALS AND METHODS: We performed BAL in 22 patients with idiopathic pulmonary fibrosis (IPF) diagnosed by open lung biopsy specimen. Percent polymorphonuclear leukocyte (PMN) in BALF and absolute neutrophil counts were compared with those of normal nonsmokers. Elastase complexed to alpha-1-proteinase inhibitor (alpha1-PI) in plasma and BALF was measured as a marker of elastase burden, and neutrophil distribution in 22 lung tissues was observed by immunohistochemistry using antineutrophil elastase antibody. RESULTS: Percent PMN and absolute neutrophil counts in BALF did not increase in patients with IPF as compared with normal nonsmokers (n=15); the plasma elastase-alpha1-PI complex value (mean+/-SE) of patients with IPF (668.5+/-112.4 ng/mL) was significantly high as compared with that of normal nonsmokers (130.3+/-21.3, p<0.001). In addition, the BALF elastase-alpha1-PI complex value (mean+/-SE) of patients with IPF was also significantly high (333.1+/-87.0 ng/mg albumin) as compared with that of normal nonsmokers (83.1+/-29.3 ng/mg albumin, p<0.05). Immunohistochemistry demonstrated considerable numbers of neutrophils infiltrating the lung parenchyma in biopsy specimens obtained by open lung biopsy. CONCLUSIONS: These results suggested that although the neutrophil count in BALF could not represent the distribution of neutrophil in the lung, high levels of neutrophil elastase were demonstrated in lung parenchyma and also in both BALF and sera. Therefore, neutrophils might indeed play an important role in the pathogenesis of IPF.     

Effects of erythromycin on surfactant synthesis, secretion, and recycling by rat alveolar type II cells

Effects of erythromycin on surfactant synthesis, secretion, and recycling by rat alveolar type II cells were examined. Type II cells were isolated from rat lungs and incubated with 3H-choline, a precursor of surfactant. Synthesis was quantified from the amount of 3H-phosphatidylcholine and from the distribution to lamellar body fractions as measured with sucrose density gradients. Secretion was quantified from the percent of synthesized 3H-phosphatidylcholine released into the medium over 3 hr. Recycling was quantified from the percent uptake over 1 h of 3H-labeled synthetic liposomes. Type II cells incubated with erythromycin (5-50 micrograms/ml) for 22 hrs secreted less surfactant in response to PMA and ATP than did control cells. Erythromycin did not affect synthesis or recycling of surfactant by type II cells. These results show that erythromycin inhibits surfactant secretion from type II cells, and suggest that erythromycin may be effective in surfactant-excess states such as alveolar proteinosis.     

Lack of evidence for P2X-purinoceptor involvement in fast synaptic responses in intact sympathetic ganglia isolated from guinea-pigs

Recordings were made from neurons in intact pre- and paravertebral guinea-pig sympathetic ganglia using intracellular microelectrodes. Fast excitatory synaptic responses were evoked by stimulation of preganglionic and peripheral nerve trunks. Suramin (0.1-1 mM) did not affect passive or active membrane properties, nor the amplitude or decay time-course of either synaptic potentials or synaptic currents. Synaptic responses were reversibly reduced in amplitude by hexamethonium (98.7 +/- 0.8%, 50-1000 microM) and d-tubocurarine (95.3 +/- 2.6%, 10-280 microM). ATP (0.5-1 mM) and alpha,beta-methylene ATP (1-40 microM) applied in the bathing solution produced no significant changes in resting membrane potential or input resistance. Prolonged application (up to 25 min) of either compound was also without effect on synaptic responses. These substances also did not affect ganglion cells axotomized one to five days in vivo. These data suggest that activation of P2X-purinoceptors is not involved in the generation of fast excitatory synaptic responses in intact guinea-pig sympathetic ganglia. It appears that dissociation of these neurons must markedly increase their sensitivity to purine nucleotides.