Identification of patterns of factors preceding severe or life-threatening asthma exacerbations in a nationwide study.

BACKGROUND: Reducing near-fatal asthma exacerbations is a critical problem in asthma management. OBJECTIVES: To determine patterns of factors preceding asthma exacerbations in a real-world setting. METHODS: In a nationwide prospective study of 190 patients who had experienced near-fatal asthma exacerbation, cluster analysis was performed using asthma symptoms over the 2-week period before admission. RESULTS: Three distinct clusters of symptoms were defined employing the self-reporting of a visual analogue scale. Cluster A (42.1%): rapid worsening within 7.4 hours from moderate attack to admission, young to middle-aged patients with low Body mass index and tendency to depression who had stopped anti-asthma medications, smoked, and hypersensitive to environmental triggers and furred pets. Cluster B (40.0%): fairly rapid worsening within 48 hours, mostly middle-aged and older, relatively good inhaled corticosteroid (ICS) or ICS/long-acting beta-agonist (LABA) compliance, and low perception of dyspnea. Cluster C (17.9%): slow worsening over 10 days before admission, high perception of dyspnea, smokers, and chronic daily mild-moderate symptoms. There were no differences in overuse of short-acting beta-agonists, baseline asthma severity, or outcomes after admission for patients in these 3 clusters. CONCLUSION: To reduce severe or life-threatening asthma exacerbation, personalized asthma management plans should be considered for each cluster. Improvement of ICS and ICS/LABA compliance and cessation of smoking are important in cluster A. To compensate for low perception of dyspnea, asthma monitoring of peak expiratory flow rate and/or exhaled nitric oxide would be useful for patients in cluster B. Avoidance of environmental triggers, increase usual therapy, or new anti-type 2 response-targeted therapies should be considered for cluster C.

Severe or life-threatening asthma exacerbation: patient heterogeneity identified by cluster analysis.

BACKGROUND: Severe or life-threatening asthma exacerbation is one of the worst outcomes of asthma because of the risk of death. To date, few studies have explored the potential heterogeneity of this condition. OBJECTIVES: To examine the clinical characteristics and heterogeneity of patients with severe or life-threatening asthma exacerbation. METHODS: This was a multicentre, prospective study of patients with severe or life-threatening asthma exacerbation and pulse oxygen saturation < 90% who were admitted to 17 institutions across Japan. Cluster analysis was performed using variables from patient- and physician-orientated structured questionnaires. RESULTS: Analysis of data from 175 patients with severe or life-threatening asthma exacerbation revealed five distinct clusters. Cluster 1 (n = 27) was younger-onset asthma with severe symptoms at baseline, including limitation of activities, a higher frequency of treatment with oral corticosteroids and short-acting beta-agonists, and a higher frequency of asthma hospitalizations in the past year. Cluster 2 (n = 35) was predominantly composed of elderly females, with the highest frequency of comorbid, chronic hyperplastic rhinosinusitis/nasal polyposis, and a long disease duration. Cluster 3 (n = 40) was allergic asthma without inhaled corticosteroid use at baseline. Patients in this cluster had a higher frequency of atopy, including allergic rhinitis and furred pet hypersensitivity, and a better prognosis during hospitalization compared with the other clusters. Cluster 4 (n = 34) was characterized by elderly males with concomitant chronic obstructive pulmonary disease (COPD). Although cluster 5 (n = 39) had very mild symptoms at baseline according to the patient questionnaires, 41% had previously been hospitalized for asthma. CONCLUSIONS & CLINICAL RELEVANCE: This study demonstrated that significant heterogeneity exists among patients with severe or life-threatening asthma exacerbation. Differences were observed in the severity of asthma symptoms and use of inhaled corticosteroids at baseline, and the presence of comorbid COPD. These findings may contribute to a deeper understanding and better management of this patient population.

Impact of intraperitoneal chemotherapy after gastrectomy with positive cytological findings in peritoneal washings.

BACKGROUND: There is no standard treatment available for gastric cancer patients whose sole 'non-curative factor' is positivecytological findings in peritoneal washings (CFPW). The aim of this study was to examine the safety, pharmacokinetics and efficacy for free intraperitoneal cancer cells of intraperitoneal chemotherapy with paclitaxel after gastrectomy with en bloc D2 lymph node dissection in cases of gastric cancer with positive CFPW. METHODS: Ten patients with gastric cancer who underwent gastrectomy and systemic lymphadenectomy with D2 dissection, without any other non-curative factors besides positive CFPW, were treated with early postoperative intraperitoneal paclitaxel. Intra-chemotherapeutic toxicity and operative complications were measured using NCI-CTC version 3.0. Intraperitoneal and plasma paclitaxel concentrations were measured using a high-performance liquid chromatographic assay. RESULTS: Grade 3/4 toxic effects included anemia (20%) and neutropenia (10%) that required no treatment. Operative complications were, for example, superficial surgical site infections (10%) that were treated with antibiotics. No viable cancer cells were observed in the intra-abdominal fluid 24 h after intraperitoneal administration of paclitaxel. The intraperitoneal/plasma area under the drug concentration-time curve ratio was 2,003.3:1. CONCLUSION: Intraperitoneal chemotherapy with paclitaxel is a safe and effective treatment modality for free intraperitoneal cancer cells.

Construction of tumor-specific cells expressing a membrane-anchored single-chain Fv of anti-ErbB-2 antibody.

Cells expressing a membrane-anchored single-chain fragment variable (scFv) domain against a tumor-specific antibody were fabricated. These cells were able to bind to cells of a human colon cancer line (BM314) expressing the erbB-2 proto-oncogene. A plasmid, pMFverbB, was first constructed in which the anti-ErbB-2 scFv gene was cloned in-frame between a signal peptide sequence and the platelet-derived growth factor receptor (PDGFR) transmembrane domain gene to express scFv on the cell surface. An African green monkey cell line, COS-1, was stably transfected with pMFverbB. Immunofluorescence assay experiments and microscopic observation showed that the cells expressing scFv bound to the human tumor cells overexpressing the ErbB-2 protein as well as to cells of a mouse fibroblast line (NIH-3T3) transfected with the erbB-2 gene. The cells expressing scFv could take up magnetite cationic liposomes as a model of particle-type drug and retained the ability to target ErbB-2-expressing cells. The fabricated cells have the potential to serve as drug carriers in drug targeting applications.

Dual axonal terminations from the retrosplenial and visual association cortices in the laterodorsal thalamic nucleus of the rat.

Light and electron microscopic tracing studies were conducted to assess the synaptic organization in the laterodorsal thalamic nucleus (LD) of the rat and the laminar origins of corticothalamic terminals from the retrosplenial and visual association cortices to LD. A survey of the general ultrastructure of LD revealed at least three types of presynaptic terminals identified on the basis of size, synaptic vesicle morphology, and synaptic membrane specializations: (1) small axon terminals with round synaptic vesicles (SR), which accounted for the majority of terminal profiles and made asymmetric synaptic contacts predominantly with small dendritic shafts and spines; (2) large axon terminals with round synaptic vesicles (LR), which formed asymmetric synaptic contacts mainly with large dendritic shafts; and (3) small to medium-size axon terminals with pleomorphic synaptic vesicles (SMP), which symmetrically synapsed with a wide range of postsynaptic structures from cell bodies to small dendrites. Synaptic glomeruli were identified, whereas no presynaptic dendrites were found. To characterize and identify corticothalamic terminals arising from the retrosplenial and visual association cortices that project to LD, wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was injected into these cortices. Axons anterogradely labeled with WGA-HRP ended in both SR and LR terminals. On the other hand, dextran-tetramethylrhodamine injected into LD as a retrograde fluorescent tracer labeled large pyramidal cells of layer V as well as small round or multiform cells of layer VI in the retrosplenial and visual association cortices. These findings provide the possibility that corticothalamic terminations from cortical neurons in layer V end as LR terminals, while those from neurons in layer VI end as SR boutons.

Mediastinoscopic extended thymectomy for pediatric patients with myasthenia gravis.

BACKGROUND: Extended thymectomy is indicated for children with myasthenia gravis (MG) when drug-resistance or dependence is seen. We have employed a technique for mediastinoscopic extended thymectomy (MET) on children with MG. METHOD: A total of 14 children underwent MET at Kanagawa Children's Medical Center between 2005 and 2013. A mediastinal operation field was made by a V-shaped hook infrasternally to extirpate the thymus with adipose tissue around the thymus. RESULTS: The operation time and the amount of blood loss were 182±44 minutes and 34±43 ml, respectively. Postoperative complications, in the form of transient paralysis of the right recurrent nerve, occurred in 2 patients. The median length of postoperative hospital stay was 4.5 days. After MET, 6 patients achieved complete remission and 7 patients achieved steroid dose reduction, but no improvement was seen in 1 patient. CONCLUSIONS: This procedure offers the advantage of good surgical access for dissection around the bilateral phrenic nerves in extended total thymectomy, while achieving good cosmetic results.

Heat-inducible TNF-alpha gene therapy combined with hyperthermia using magnetic nanoparticles as a novel tumor-targeted therapy.

Heat-induced therapeutic gene expression is highly desired for gene therapy to minimize side effects. Furthermore, if the gene expression is triggered by heat stress, combined therapeutic effects of hyperthermia and gene therapy may be possible. We combined TNF-alpha gene therapy driven by the stress-inducible promoter, gadd 153, with hyperthermia using magnetite cationic liposomes (MCLs). In nude mice, MCLs induced cell death throughout much of the tumor area on heating under an alternating magnetic field. This heat stress also resulted in a 3-fold increase in TNF-alpha gene expression driven by the gadd 153 promoter as compared with that of nonheated tumor. TNF-alpha gene expression was also observed in the peripheral area where the hyperthermic effect was not enough to cause cell death. The combined treatment strongly arrested tumor growth in nude mice over a 30-day period, suggesting potential for cancer treatment.

Contrasting effects of tachykinins and guanethidine on the acetylcholine output stimulated by nicotine from guinea-pig bladder [corrected].

1. Contractile responses and acetylcholine release evoked by nicotine in guinea-pig detrusor strips were determined by isotonic transducer and radioimmunoassay, respectively. Nicotine stimulated acetylcholine release and a contractile response in guinea-pig detrusor strips treated with the cholinesterase inhibitor, methanesulphonyl fluoride (MSF). Both actions evoked by nicotine were antagonized by the nicotinic receptor antagonist, hexamethonium but were insensitive to tetrodotoxin. 2. A sympathetic nerve blocker, guanethidine and a tachykinin antagonist, [D-Arg1, D-Pro2, D-Trp7,9, Leu11]-substance P (rpwwL-SP) partially inhibited the acetylcholine release evoked by nicotine to much the same degree. The inhibitory effects of guanethidine and rpwwL-SP on acetylcholine release were significantly greater than corresponding effects on the contraction evoked by nicotine. 3. In preparations treated with rpwwL-SP to block the tachykinin receptors, guanethidine had no effect on the response to nicotine. Conversely, after treatment with guanethidine to block release of a mediator from sympathetic nerve endings, nicotine-induced responses were not affected by rpwwL-SP. 4. Nicotine-induced contraction was reduced to 30% by the muscarinic cholinoceptor antagonist, atropine and completely abolished after desensitization of P2-purinoceptors with alpha,beta-methylene ATP in the presence of atropine. 5. A concentration-contractile response curve to neurokinin A (NKA) was shifted to the left after cholinesterase inhibition with MSF. Atropine abolished the facilitatory effect of MSF and partially inhibited contractions induced by NKA at 100 nM to 1 microM. The contractile responses to substance P methyl ester (SPOMe) and Tyr0-neurokinin B (Tyr0-NKB) were not influenced by MSF or atropine. 6. After desensitization of NK, tachykinin receptors with SPOMe or preincubation with senktide, the cholinergic component of the nicotine-induced contraction was the same as the control value (100%). 7. Our findings give further support to our previous results: nicotine stimulates acetylcholine release in a tetrodotoxin-resistant manner in guinea-pig bladder and acetylcholine release evoked by nicotine is increased by the coordinated action of sympathetic nerves and tachykinin(s). It is suggested that the tachykinin receptor subtype involved in acetylcholine release is NK,.

Tachykinin receptors of the NK2 type involved in the acetylcholine release by nicotine in guinea-pig bladder.

1. The effects of guanethidine and tachykinins on nicotine- and electrical stimulation-induced cholinoceptor responses were studied in isolated urinary bladder from the guinea-pig. 2. Acetylcholine release and the contractile response stimulated by nicotine were partially reduced by a sympathetic nerve blocker, guanethidine. Neurokinin A (but not substance P methyl ester or senktide) enhanced both acetylcholine release and contraction by nicotine in the presence of guanethidine. 3. Frequency-contraction curves (1 to 50 Hz) for electrical field stimulation (EFS) were partially reduced by atropine (1 microM), and after desensitization to alpha,beta-methylene adenosine 5'-triphosphate, the atropine-resistant contraction to EFS was completely abolished. Guanethidine, the tachykinin antagonist [D-Arg1, D-Pro2, Trp7,9, Leu11]-substance P and application of neurokinin A or substance P did not change the contractile response to EFS. Preganglionic nerve stimulation (5 Hz and 20 Hz) also evoked a similar response to EFS and was not influenced at all by guanethidine or neurokinin A. 4. We conclude that the ability of nicotine to release acetylcholine is enhanced both by endogenous tachykinins (probably released from sympathetic nerves) and by exogenously applied tachykinins as a result of interaction with NK2 receptors in the urinary bladder.

Mechanism of action of nicotine in isolated urinary bladder of guinea-pig.

1. Nicotine produced a transient contraction of isolated strips of guinea-pig urinary bladder. The response to nicotine was antagonized by the nicotinic receptor antagonist, hexamethonium but was insensitive to tetrodotoxin. 2. The nicotine-induced contraction was potentiated by the cholinesterase inhibitor, physostigmine, and was reduced to 50% and 70% by the muscarinic cholinoceptor antagonist, atropine and the sympathetic neurone blocking drug, guanethidine, respectively. Chemical denervation with 6-hydroxydopamine abolished the inhibitory effect of guanethidine. Simultaneous treatment with atropine and guanethidine did not abolish the response to nicotine, but the degree of inhibition was comparable to that obtained with atropine alone. 3. The nicotine-induced contraction was insensitive to bunazosin and yohimbine (alpha 1- and alpha 2-adrenoceptor antagonists, respectively), and exogenously applied noradrenaline did not cause a contraction even in the presence of blockade of noradrenaline uptake mechanisms with desipramine and normetanephrine and of beta-adrenoceptors with propranolol, suggesting a non-adrenergic nature of the sympathomimetic effect of nicotine in this tissue. 4. The nicotine-induced contraction in the presence of atropine was abolished after desensitization of P2-purinoceptors with alpha, beta-methylene adenosine 5'-triphosphate, a slowly degradable ATP analogue selective for P2-purinoceptors. By this desensitization, the response to ATP, but not to histamine, was also abolished. 5. A cyclo-oxygenase inhibitor flurbiprofen partially inhibited the nicotine-induced contraction. The degree of the inhibition was more pronounced in the presence of atropine than in its absence. Flurbiprofen antagonized the response to exogenously applied ATP in an unsurmountable manner, but not that to carbachol. 6. The present results suggest that nicotine might induce a contraction through an interaction with nicotinic receptors located on the terminals of, possibly, (i) parasympathetic cholinergic, (ii) sympathetic non-adrenergic and (iii) non-sympathetic purinergic nerves in guinea-pig detrusor preparations, and that a portion of the contraction due to the purine nucleotide released is possibly potentiated by intramural prostaglandin(s). Parasympathetic cholinergic output might be modulated by an unknown excitatory substance released by nicotine from sympathetic nerve. 7. Nicotine reveals a latent excitatory effect of the sympathetic hypogastric nerve which innervates guinea-pig detrusor.

Mechanism of action of nicotine in isolated iris sphincter preparations of rabbit.

1. Nicotine produced a transient contraction of rabbit isolated iris sphincter muscle, a parasympathetic ganglion-free tissue. The response to nicotine was antagonized by hexamethonium, but was insensitive to tetrodotoxin (TTX). While single treatments with atropine, capsaicin or [D-Arg1, D-Pro2, D-Trp7,9, Leu11]-substance P (rpwwL-SP) partially blocked the response, combined treatment abolished it. 2. Chronic treatment of animals with nicotine added to the drinking water (about 12 mg kg-1 per day) had no effect on the responsiveness to nicotine or the pharmacological properties of nicotine-induced contraction. 3. These results suggest that acetylcholine and tachykinin(s) released via sodium channel-independent mechanisms from nerve terminals of parasympathetic and primary sensory nerves, respectively, are involved in the nicotine-induced contractile response.

Synergism between mild hyperthermia and interferon-beta gene expression.

In the present study, the synergistic effect of mild hyperthermia in combination with gene expression of interferon-beta (IFN-beta) was examined in vitro in the human glioma cell line U87MG. The cells transiently expressed the IFN-beta gene under the control of the mouse mammary tumor virus promoter and were then subjected to temperature elevation (41 degrees C for 1 h). In terms of the cell killing effect, the optimum scheme was obtained by transfection for 4 days before hyperthermia, i.e. rate in the time course of IFN-beta gene expression. The relative specific growth rate decreased to 32% compared with the control while it was only 40% under the hyperthermic conditions. These observations suggest that IFNbeta expression was able to enhance the sensitivity of transfected glioma cells to mild hyperthermia.

Macrophage-derived transforming growth factor-beta1 induces hepatocellular injury via apoptosis in rat severe acute pancreatitis.

BACKGROUND: The mechanism of acute pancreatitis-induced hepatocellular injury is unclear. We have observed hepatocyte apoptosis in rat acute necrotizing pancreatitis. These studies were designed to determine the mediator(s) responsible for hepatocyte apoptosis and to clarify the significance of macrophages as its source. METHODS: A rat sodium deoxycholate-induced pancreatitis model was used. Immunohistochemical studies for apoptosis-inducing mediators on hepatocytes were examined in the liver and on the peritoneal macrophages. The levels of transforming growth factor-beta1 (TGF-beta1) were also evaluated quantitatively with an enzyme-linked immunosorbent assay. Induction of apoptosis on the hepatocytes was evaluated by in situ nick-end labeling and tissue DNA fragmentation enzyme-linked immunosorbent assay. Finally, the effects of TGF-beta1 neutralization and macrophage depletion were examined. RESULTS: In the liver and the peritoneal macrophages, strong expression of TGF-beta1 was detected early in the course of pancreatitis. In sodium deoxycholate-induced pancreatitis, the levels of TGF-beta1 were also elevated in the plasma (9.2 +/- 0.8 ng/mL), in the pancreatitis-associated ascitic fluid (11.5 +/- 0.6 ng/mL), and in the liver homogenate (2.8 +/- 0.3 ng/g of liver tissue). Moreover, the amount of fragmented DNA of the liver with pancreatitis was 290% +/- 20% of that with a sham operation and serum alanine aminotransferase levels elevated to 248.2 +/- 67.0 IU/L. TGF-beta1 neutralization partly blocked the positive labeling on the nuclei of the hepatocytes, the elevation of the amounts of fragmented DNA (205% +/- 10% of sham operation), and the serum alanine aminotransferase level (144.2 +/- 14.9 IU/L). On the other hand, the macrophage depletion caused a marked decrease in the TGF-beta1 protein level in the plasma (4.8 +/- 1.2 ng/mL) or in the pancreatitis-associated ascitic fluid (8.0 +/- 1.0 ng/mL). Moreover, the macrophage depletion completely inhibited the elevation of the TGF-beta1 protein level in the liver homogenate (1.5 +/- 0.4 ng/g of liver tissue), and thereafter decreased the amounts of the positive labeling on the nuclei of the hepatocytes and decreased the amount of fragmented DNA (120% +/- 18% of sham operation) and the serum alanine aminotransferase elevation (119.2 +/- 24.2 IU/L). CONCLUSIONS: In a model of sodium deoxycholate-induced pancreatitis, macrophages are responsible for pancreatitis-induced hepatocellular injury by means of apoptosis, and macrophage-derived TGF-beta1 is one of the major factors inducing the hepatocyte apoptosis.

Effect of tachykinins on the acetylcholine output stimulated by nicotine from guinea-pig bladder.

Effects of tachykinins on contractile responses and acetylcholine release evoked by nicotine were determined by isotonic transducer and radioimmunoassay. A sympathetic nerve blocker guanethidine and tachykinin antagonist, [D-Arg1,D-Pro2,D-Trp7,9,Leu11]-substance P (rpwwL-SP) partially inhibited the acetylcholine release evoked by nicotine to much the same degree. In preparations treated with rpwwL-SP to block the tachykinin receptors, guanethidine had no effect on the response to nicotine and vice versa, suggesting an exclusive contribution of the sympathetic nerve communications to the action of tachykinins. A concentration response curve to neurokinin A but not SP methyl ester or Tyr0-neurokinin B was shifted to the left after cholinesterase inhibition with methanesulphonyl fluoride (MSF) and was partially inhibited by atropine. In the presence of guanethidine, an acetylcholine output by nicotine was facilitated in the presence of neurokinin A (10 nM) but not SP methyl ester (10 nM) or senktide (10 nM). These results indicate that acetylcholine release evoked by nicotine is increased by the coordinated action of sympathetic nerves and tachykinins. Tachykinin receptor subtype involved in acetylcholine release is NK2.

Postoperative flow characteristics of left internal thoracic artery grafts.

Twenty patients whose left internal thoracic artery (LITA) was anastomosed to the left anterior descending artery (LAD) underwent postoperative coronary angiography and Doppler ultrasound velocimetry. During angiography, the diameter of the LITA conduit was measured at three points: proximal, mid, and distal. The degree of left anterior descending artery stenosis proximal to the anastomotic site was evaluated by densitometry. The LITA flow velocity pattern was obtained at the three points to calculate the total, systolic, and diastolic flow volume. There were significant differences in the total LITA flow among the three points (proximal, 36.0 +/- 17.2 mL/min; mid, 29.9 +/- 15.2 mL/min; distal, 27.2 +/- 14.0 mL/min; p < 0.001 between the proximal and the mid or distal portions). The degree of left anterior descending artery stenosis affected the distal LITA flow and diameter (r = 0.823 and 0.811, respectively). There were significant differences in the systolic LITA flow among the three points (proximal, 13.2 +/- 6.5 mL/min; mid, 8.1 +/- 4.7 mL/min; distal, 5.6 +/- 3.4 mL/min; p < 0.001 between the proximal and the mid or distal portions). However, there was no statistically significant difference in the diastolic LITA flow among the three points (proximal, 22.9 +/- 11.0 mL/min; mid, 21.7 +/- 10.8 mL/min; distal, 21.6 +/- 10.8 mL/min). We conclude that a lower degree of LAD stenosis significantly reduces the LITA flow, inducing the string phenomenon. Additionally, during the diastolic phase, the LITA graft transports the blood primarily to the coronary artery but not to the side branches. Therefore, the steal phenomenon might not apply in the setting of an LITA graft.

Direct synaptic connections between thalamocortical axon terminals from the mediodorsal thalamic nucleus (MD) and corticothalamic neurons to MD in the prefrontal cortex.

A combined anterograde axonal degeneration with ibotenic acid and wheat germ agglutinin-horseradish peroxidase (WGA-HRP) retrograde tracing study revealed that some degenerating thalamocortical axon terminals from the mediodorsal thalamic nucleus (MD) directly formed asymmetrical synaptic contacts predominantly with dendritic spines of apical dendrites of WGA-HRP-labeled corticothalamic projection neurons to MD in the prelimbic cortex of the rat. This result suggests that there is a monosynaptic feedback loop from and to MD via deeper layer neurons in the prelimbic cortex.

Electron microscopic evidence that axon terminals from the mediodorsal thalamic nucleus make direct synaptic contacts with callosal cells in the prelimbic cortex of the rat.

A combined study of anterograde axonal degeneration and HRP retrograde labeling has shown that there exist monosynaptic connections between afferent fibers from the mediodorsal thalamic nucleus (MD) and callosal cells in the prelimbic cortex of the rat. Degenerating axon terminals from MD made asymmetrical synaptic contacts with dendritic spines from apical dendrites of layer III pyramidal cells that were retrogradely labeled with HRP after its injection into the prelimbic cortex contralateral to MD lesions.

Synaptic relationships between axon terminals from the mediodorsal thalamic nucleus and layer III pyramidal cells in the prelimbic cortex of the rat.

A combined study of anterograde axonal degeneration and Golgi electron microscopic technique was designed to examine the distribution and density of axon terminals from the mediodorsal thalamic nucleus (MD) over layer III pyramidal cells in the prelimbic cortex of the rat. The reconstructive analysis of serial ultrathin sections of gold-toned apical and basal dendrites of layer III pyramidal cells showed that degenerating thalamocortical axon terminals from MD formed asymmetrical synaptic contacts predominantly with dendritic spines of the identified basal dendrites as well as apical dendrites. There was little difference in the numerical density of thalamocortical synapses from MD per unit length of both apical and basal dendrites.

Hepatocyte growth factor increases in injured organs and functions as an organotrophic factor in rats with experimental acute pancreatitis.

We previously reported that serum hepatocyte growth factor (HGF) levels are elevated in patients with acute pancreatitis and that pancreatitis-associated ascitic fluid (PAAF) contains cytotoxic factor(s) inducing apoptosis on Madin-Darby canine kidney (MDCK) cells. In this study, plasma HGF levels and HGF tissue distribution were investigated in rats with experimental acute pancreatitis, and the effects of HGF on the cytotoxic activity and apoptosis-inducing activity of PAAF also were examined. Plasma HGF levels were elevated in rats with two experimental pancreatitis models of different grades of severity. The degree of its elevation was correlated with the severity and the organ dysfunctions. In rats with severe pancreatitis, HGF protein and messenger RNA (mRNA) levels significantly increased in liver, kidney, and lung, which were injured organs. When anti-HGF neutralizing antibody was administered in severe pancreatitis, liver dysfunction worsened, and apoptotic cells increased in kidney. Recombinant HGF inhibited the cytocidal activity of PAAF on MDCK cells in a dose-dependent manner. Moreover, recombinant HGF prevented the apoptotic cell death (DNA fragmentation, nuclear fragmentation, and caspase-3 activation) induced by PAAF. These results suggest that HGF is produced in injured organs and may function as an organotrophic and antiapoptotic factor against the organ injuries in acute pancreatitis.

Pre- and postjunctional actions of endothelin in the rat iris sphincter preparation.

Effects of endothelins (ETs) were studied in the rat iris sphincter preparation. Three peptides (ET-1, ET-2 and ET-3) caused contractile responses, and the rank order of agonist potency was: ET-1 = ET-2 > ET-3. The concentration-response curve to ET-1 was shifted to the right by the ETA receptor antagonist cyclo [D-Asp-L-Pro-D-Val-L-Leu-D-Trp] (BQ-123: 10(-7) M), the pA2 value of which was 7.41 +/- 0.09 (n = 4). ET-1 and ET-3, at the concentration of 10(-9) M, potentiated cholinergic contractions evoked by electrical field stimulation (5 and 20 Hz) without affecting the postjunctional sensitivity to carbachol. This potentiating effect was not influenced by BQ-123 (10(-6) M). The ET-evoked percentage increase in the stimulation-induced contraction observed at 5 Hz was significantly greater than that at 20 Hz. A release of immunoreactive ET was detected when the preparation was stimulated at 20 Hz (1.81 +/- 0.36 pg/sphincter n = 6). ET release evoked by 20 Hz stimulation was completely abolished by tetrodotoxin (10(-7) M). In conclusion, ET interacts with two different receptor types, ETA and non-ETA receptors (probably ETB) which exist post- and presynaptically at cholinergic neuroeffector junctions of the rat iris preparation. Stimulation of ETA receptor results in a direct muscle contraction and non-ETA receptor activation facilitates the acetylcholine output from cholinergic nerve endings. It is suggested that ET released from a tetrodotoxin-sensitive site is involved in the modulation of acetylcholine release in the rat iris sphincter preparation.