Morphological comparison and functional reconstitution of rat hepatic parenchymal cells on various matrices

Four types of materials, type I collagen coat (Coat), acid-soluble type I collagen gel (Hardgel), pepsin-treated acid-soluble type I collagen gel (Softgel), and an extract of extracellular matrix of the murine Engelbreth-Holm-Swarm sarcoma (Matrigel), were used as matrices to culture rat hepatic parenchymal cells, and their morphological changes and adhesion were compared to the matrices by electron microscopic observations. Hepatic parenchymal cells cultured on Coat and Hardgel were extended and flattened, whereas cells cultured on Softgel and Matrigel assembled and formed aggregates. Such aggregates consisted of several hepatic parenchymal cells, with a recognizable bile duct-like alveolus on the inside. Morphologically, the aggregates were more spherical on Matrigel and oval shaped on Softgel. Microvilli of the cell surface were parallel to the matrix on Matrigel, but invaded into the gel on Softgel. Subsequently, investigation into how these morphological features affected the liver-specific functions, including secretion of albumin and induction of P450 by 3-methylcholanthrene, demonstrated that a high level of liver function was maintained in a long-term culture in hepatic parenchymal cells on Softgel. These results suggest that hepatic parenchymal cell interactions were stronger with Softgel than with Matrigel, and that Softgel appears to closely mimic the in vivo environment.     

‘Lung age’ predicts post‐operative complications and survival in lung cancer patients

Background and objective: The Japanese Respiratory Society recently proposed ‘lung age’ as an easily understood concept of respiratory function. In this study, we evaluated whether ‘lung age’ could be a useful predictor of post‐operative respiratory complications and survival patients with lung cancer treated surgically. Methods: The study recruited 308 patients who underwent surgery for primary non‐small‐cell lung cancer. All patients had preoperative pulmonary function testing. ‘Lung age’ was determined using the methods advocated by the Japanese Respiratory Society. Based on the difference between ‘real age’ (R) and ‘lung age’ (L), patients were classified into five groups: group A: R?L > 15 (n = 37), B: 5 < R?L ≤ 15 (n = 50), C: ?5 ≤ R?L ≤ 5 (n = 73), D: ?15 ≤ R?L < ?5 (n = 54), E: ?15 > R?L (n = 94). Clinicopathological factors, post‐operative respiratory complications and survival were compared between the groups. Results: Gender, smoking status and index, histology, operative approach and FEV₁ were significantly associated with the group classification. The incidence of complications was significantly higher in group E compared with other groups (P = 0.003). Multivariate analysis showed that the group classification by ‘lung age’ was an independent predictor of post‐operative respiratory complications (P = 0.02). Overall survival differed significantly between the groups (P = 0.03). Conclusions: ‘Lung age’ could be useful for the prediction of post‐operative respiratory complications and survival in patients with lung cancer treated surgically.     

FUNCTIONAL AND METABOLIC EFFECTS OF BUPIVACAINE AND LIGNOCAINE IN THE RAT HEART-LUNG PREPARATION

We have examined the effects of bupivacaine and lignocaine onmyocardial metabolism in the rat isolated heart-lung preparation.Bupivacaine 1, 5 or 25 µg ml^–1 or lignocaine 4,20 or 100 µg ml^–1 was administered 5 min after thestart of perfusion. Both bupivacaine 25 µg ml^–1and lignocaine 100 µg ml^–1 reduced heart rate significantly.Bupivacaine 25 µg ml^–1 was associated with a higherincidence of arrhythmias than the other groups. Three heartsin the bupivacaine 25 µg ml^–1 group (n = 8) andtwo hearts in the lignocaine 100 µg ml^–1 group (n= 8) failed (zero cardiac output) at the end of the experiment.Although there were no significant differences in myocardiallactate and glycogen concentrations between groups, ATP contentin the bupivacaine 25 µg ml^–1 and lignocaine 100µg ml^–1 groups was significantly less than thatin the control group. The results suggest that myocardial depressionand subsequent metabolic deterioration occurred with both thehigh doses of local anaesthetics; these findings do not accountfor the apparent increased cardiotoxicity of bupivacaine.     

Effects of artificial blood (FC-43 emulsion) on myocardial energy metabolism in the rat heart-lung preparation

We have assessed the effects of artificial blood (FC-43 emulsion)on myocardial energy metabolism in the rat heart-lung preparation.Animals were allocated to four groups (n = 8 each group) accordingto the ratio of perfusion blood and FC-43 as follows: group1 = control, perfusion blood only; group 2 = 50% FC-43; group3 = 75% FC-43; and group 4 = 100% FC-43. Hearts were perfusedinitially to a cardiac output of 30 ml min^–1 and meanarterial pressure of 50 mm Hg. Thirty minutes after perfusion,the hearts were freeze-dried for 6 days. Myocardial high energyphosphates (ATP, ADP and AMP) were measured by high pressureliquid chromatography. Myocardial lactate and glycogen concentrationswere measured by enzymatic methods. There were almost no significantdifferences in cardiac output, systolic pressure, right atrialpressure and heart rate among the groups. Oxygen contents ofthe perfusate in all FC-43 groups were significantly lower thanthose in the control group. Myocardial ATP concentrations inrats receiving 50%, 75% and 100% FC-43 were significantly lowerthan those in the control group. In addition, myocardial ADPand AMP concentrations in rats receiving 75% and 100% FC-43were significantly higher than those in the control group. Althoughthere is adequate oxygen-carrying capacity in FC-43 to maintaincardiac function during perfusion, the energy levels in thehearts perfused with FC-43 were lower than those in normal hearts.     

CLINICOPATHOLOGICAL,IMMUNOLOGICAL AND GENETIC STUDIES OF CD30+ ANAPLASTIC LARGE CELL LYMPHOMA OF B-CELL TYPE; ASSOCIATION WITH EPSTEIN–BARR VIRUS IN A JAPANESE POPULATION

The clinicopathological features, the immunophenotype, and the presence of Epstein–Barr virus (EBV)-associated genomes and gene products were examined in 17 cases of CD30⁺ anaplastic large cell lymphoma (ALCL) of B-cell type. Microscopically, the 17 cases were divided into ten cases of the monomorphic type and seven cases of the pleomorphic type. EBV was detected in 6 of 17 cases (38 per cent) by RNA in situ hybridization (ISH) with EBV-encoded RNA (EBER1). EBER1⁺ cases consisted of two cases (20 per cent) of the monomorphic type and four cases (57 per cent) of the pleomorphic type. The five EBER1⁺ cases showed clonality of the EBV genome by Southern blotting, consistent with the presence of EBV in a monoclonal proliferation. The EBV-encoded latent membrane protein 1 (LMP1) was found in all six EBER1⁺ cases and EBV-encoded nuclear antigen 2 (EBNA2) was present in two cases by immunohistochemistry. No expression of LMP1 or EBNA2 was observed in the EBER1⁻ cases. The EBER1⁺ cases had a tendency for a more favourable prognosis than the EBER1⁻ cases. It is concluded that EBV has an association with CD30⁺ ALCL of B-cell type in the Japanese population studied, and especially with the large pleomorphic type. EBV infection may play a pathoaetiological role and may influence clinical behaviour.     

Renoprotective effects of asialoerythropoietin in diabetic mice against ischaemia–reperfusion-induced acute kidney injury

Aim: Diabetic patients are at higher risk of failure to recover after acute kidney injury, however, the mechanism and therapeutic strategies remain unclear. Erythropoietin is cytoprotective in a variety of non‐haematopoietic cells. The aim of the present study was to clarify the mechanism of diabetes‐related acceleration of renal damage after ischaemia–reperfusion injury and to examine the therapeutic potential of asialoerythropoietin, a non‐haematopoietic erythropoietin derivative, against ischaemia–reperfusion‐induced acute kidney injury in diabetic mice. Methods: C57BL/6J mice with and without streptozotocin‐induced diabetes were subjected to 30 min unilateral renal ischaemia–reperfusion injury at 1 week after induction of diabetes. They were divided into four group: (i) non‐diabetic plus ischaemia–reperfusion injury; (ii) non‐diabetic plus ischaemia–reperfusion injury plus asialoerythropoietin (3000 IU/kg bodyweight); (iii) diabetic plus ischaemia–reperfusion injury; and (iv) diabetic plus ischemia–reperfusion injury plus asialoerythropoietin. Experiments were conducted at the indicated time periods after ischaemia–reperfusion injury. Results: Ischaemia–reperfusion injury of diabetic kidney resulted in significantly low protein expression levels of bcl‐2, an anti‐apoptotic molecule, and bone morphogenetic protein‐7 (BMP‐7), an anti‐fibrotic and pro‐regenerative factor, compared with non‐diabetic kidneys. Diabetic kidney subsequently showed severe damage including increased tubular cell apoptosis, tubulointerstitial fibrosis and decreased tubular proliferation, compared with non‐diabetic kidney. Treatment with asialoerythropoietin induced bcl‐2 and BMP‐7 expression in diabetic kidney and decreased tubular cell apoptosis, tubulointerstitial fibrosis and accelerated tubular proliferation. Conclusion: Reduced induction bcl‐2 and BMP‐7 may play a role in the acceleration of renal damage after ischaemia–reperfusion injury in diabetic kidney. The renoprotective effects of asialoerythropoietin on acute kidney injury may be mediated through the induction of bcl‐2 and BMP‐7.     

Effects of JTV-506, a new K+ channel activator, on airway smooth muscle contraction and systemic blood pressure

Background ATP-sensitive K⁺ (K_ATP) channel activators produce relaxation of smooth muscle in many tissues. However, this wide range of effects restricts their clinical usefulness in bronchial asthma because of a reduction in systemic blood pressure. Methods We have now examined the effects of JTV-506, a new benzopyran derivative, on airway smooth muscle contraction and systemic blood pressure and have compared this compound with cromakalim. We measured isometric tension records from guinea-pig isolated trachea, as well as the respiratory resistance (R_rs) and systemic blood pressure in anesthetized guinea-pigs. Results JTV-506 caused a concentration-dependent inhibition of histamine-induced contraction in guinea-pig isolated tracheal smooth muscle, and was antagonized by glibenclamide. JTV-506 was 7.6-fold more potent than cromakalim. In anesthetized animals the intravenous injection of JTV-506 reduced the increase in R_rs induced by intravenous application of 5 μg/kg of histamine in a dose-dependent manner, 10μ/kg of JTV-506 resulted in 57.0 17.9% inhibition of the increase in R_rs at 10 min. The inhibitory action on R_rs disappeared after 60 min. 10μg/kg of cromakalim caused 25.4 ± 5.8% inhibition of the increase in R_rs induced by histamine at 1 min. The ED₅₀ values for JTV-506 and cromakalim were 6.7 ± 3.5μg/kg and 60.1 ± 15.8μg/kg, respectively (P<0.05). Cromakalim was ± 9-fold less potent in inhibiting the increased R_rs by histamine. and the inhibitory action lasted less than 10 min. The reduction of systemic blood pressure by JTV-506 and cromakalim (each at a dose of 10μg/kg iv) was 11.3% and 21.5%, respectively Conclusion JTV-506 inhibits histamine-induced contraction of tracheal smooth muscle by activation of K_ATP channels. This compound is more potent and longer-lasting in the suppression of histamine-induced increases in R_rs, and is less hypotensive than cromakalim. Our results suggest that this compound merits further investigation for utility as a bronchodilator in the clinic.