A unique method for predicting cardiorespiratory fitness using rating of perceived exertion

The purpose of this study was to develop a simple and convenient indirect method for estimating maximal oxygen uptake (VO2max) and oxygen uptake at the anaerobic threshold (VO2AT) by using workrate and a rating of perceived exertion (RPE) during a submaximal graded cycling test (GCTsubmax). One hundred and fifty-four healthy Japanese men, aged 20 to 64 years, volunteered to participate in the study. The subjects were randomly divided into two groups, a validation (V) group (n = 100) and a cross-validation (CV) group (n = 54). The V and CV groups performed a maximal cycling test and the GCTsubmax. The GCTsubmax was conducted with documentation of three categories (overall, chest, legs) of RPE, up to a rating of 15. Prediction equations of VO2max and VO2AT were developed by multiple regression analysis using data of the V group. The mean VO2max and VO2AT of the V group were 2462 +/- 484 ml.min-1 and 1349 +/- 334 ml.min-1, respectively. Correlational analyses indicated that the workrate (W) at which the legs RPE (RPElegs) reached 15 or higher was evaluated first (WRPE legs 15) together with WRPE legs 14 both yielded the highest correlation coefficients (r) with VO2max (r = 0.781) and V O2AT (r = 0.790), respectively. The developed prediction equations of VO2max and VO2AT were VO2max (ml.min-1) = 1.19 WRPE legs 15 (kgm.min-1) - 15.84 age (yr) + 13.06 weight (kg) + 1365 (R = 0.849, SEE = 261 ml.min-1) VO2AT (ml.min-1) = 1.34 WRPE legs 14 (kgm.min-1) - 5.49 age (yr) + 665 (R = 0.816, SEE = 195 ml.min-1) Results of a cross-validation analysis indicated a similar estimation (r = 0.793 and 0.853, and SEE = 240 ml.min-1 and 183 ml.min-1) compared with the above equations developed from data of the V group. Reliability coefficients of V O2max (r = 0.891) and VO2AT (r = 0.870) respectively were significant and there was no difference in the mean value between trials 1 and 2. The "RPE method" developed for estimating cardiorespiratory fitness is not only a unique indirect method but also a valid and useful tool in various settings of exercise prescription.

Successfully treated composite graft infection after Bentall's procedure

A 47-year-old male patient underwent Bentall's modification with total arch replacement owing to type A acute dissection. Mediastinitis and composite graft infection occurred 3 weeks after the operation. Extensive debridement and irrigation followed by omental wrapping without graft removal were performed and the patient was successfully cured.

Peroxisome proliferator-activated receptor-gamma activation inhibits interleukin-1beta -mediated platelet-derived growth factor-alpha receptor gene expression via CCAAT/enhancer-binding protein-delta in vascular smooth muscle cells

CCAAT/enhancer-binding protein (C/EBP)-binding motifs have been identified in the promoter regions of interleukin (IL)-6, tumor necrosis factor-alpha, and platelet-derived growth factor-alpha receptor (PDGFalphaR). Recently, peroxisome proliferator-activated receptors (PPARs) have been suggested to be important immunomodulatory mediators. Although many studies have demonstrated that the interaction between C/EBPs and PPARs plays a central role in lipid metabolism, expression and function of these factors are unknown in vascular smooth muscle cells (VSMCs). In the present study, we clarified a functional relationship between C/EBPs and PPARgamma in the regulation of IL-1beta-induced PDGFalphaR expression in VSMCs. PPARgamma activators, troglitazone and 15-deoxy-Delta(12,14)-prostaglandin J(2), inhibited IL-1beta-induced PDGFalphaR expression and suppressed PDGF-induced proliferation activity of VSMCs. Electromobility shift and supershift assays for a C/EBP motif in the PDGFalphaR promoter region revealed that PPARgamma activators suppressed IL-1beta-induced DNA binding activity of C/EBPdelta and beta. PPARgamma activators also suppressed IL-1beta-induced C/EBPdelta expression. In contrast, overexpression of C/EBPdelta reversed the suppressive effect of PPARgamma activators on PDGFalphaR expression almost completely. From these results, we conclude that the inhibitory effect of PPARgamma activators on PDGFalphaR expression is mainly mediated by C/EBPdelta suppression. Regulation of C/EBPdelta by PPARgamma activators probably plays critical roles in modulating inflammatory responses in the arterial wall.

Role of GADD153 (growth arrest- and DNA damage-inducible gene 153) in vascular smooth muscle cell apoptosis

GADD153 (growth arrest- and DNA damage-inducible gene 153) is expressed at very low levels in growing cells, but is markedly induced in response to a variety of cellular stresses, including glucose deprivation, exposure to genotoxic agents and other growth-arresting situations. Forced expression of GADD153 induces cell cycle arrest in many types of cells. It is also reported that GADD153 is directly associated with apoptosis. Recently we have reported that platelet-derived growth factor (PDGF)-BB induces apoptosis in cultured vascular smooth muscle cells (VSMC), but only when 100% confluency is reached. These results suggested that cell-cell contact inhibition (cell growth arrest) may be a critical factor for induction of VSMC apoptosis by PDGF-BB. In the present study, we explored the role of GADD153, one of a number of growth-arrest-related gene products, in the molecular mechanisms of VSMC apoptosis in vitro and in vivo. GADD153 was markedly induced at both the mRNA and protein levels, in parallel with the induction of VSMC apoptosis, after treatment with PDGF-BB. Moreover, overexpression of GADD153 in VSMC significantly reduced cell viability and induced apoptosis. In the carotid artery balloon injury model in rats, GADD153 protein was expressed in apoptotic VSMC which were positively stained by in situ DNA labelling. These results demonstrate an important role for GADD153 in the molecular mechanisms of VSMC apoptosis.

Hypoglycemic syncope induced by a combination of cibenzoline and angiotensin converting enzyme inhibitor

A 65-year-old Japanese woman with dilated cardiomyopathy, hypothyroidism and refractory sustained ventricular tachycardia experienced a near-death hypoglycemic syncope. The attack seemed to be induced by a high level of serum insulin, probably due to cibenzoline and by concomitant use of an angiotensin converting enzyme inhibitor (ACEI). Additionally, decreased food intake because of a severe toothache may have contributed to the deterioration of her condition. This case warns cardiologists that a combined cibenzoline and ACEI therapy can provoke serious adverse effects such as hypoglycemic syncope in the elderly. Therefore, the possibility of a hypoglycemic attack associated with these drugs should be explained to patients who are in poor condition.

Nuclear factor 1 is a negative regulator of gadd153 gene expression in vascular smooth muscle cells

Growth arrest and DNA damage inducible gene 153 (gadd153) is expressed at very low levels in growing cells but is markedly induced in response to cellular stresses, including glucose deprivation, exposure to genotoxic agents, and other growth-arresting situations. Forced expression of GADD153 can induce cell cycle arrest and/or apoptosis in many types of cells. Recently, we reported that GADD153 was induced in vascular smooth muscle cells (VSMCs) in neointimal lesions of balloon-injured carotid arteries. To investigate the underlying molecular mechanisms of gadd153 gene expression in VSMCs, we isolated and characterized a promoter region of the rat gadd153 gene. Sequence alignments of this region revealed 1 TATA-like sequence and several well-known cis elements. The 5'-deletion analysis for this region showed that a domain spanning -447 through -368 drastically reduced the promoter activity to almost equal levels of promoterless control. Because this domain contained a consensus sequence for the nuclear factor 1 family of proteins (NF1), DNA-binding studies were performed by use of 2 types of NF1 consensus probes. Both probes were specifically shifted by nuclear extracts from proliferating VSMCs and were supershifted by antiserum against CCAAT transcription factor/NF1. In addition, promoter activity of a mutant luciferase vector, which was generated by a point mutation at the NF1 binding motif of the gadd153 gene, was 14-fold higher than that of a wild-type one. These results suggest that gadd153 gene expression in VSMCs is negatively regulated by an NF1-binding motif, and NF1 may act as an antiapoptotic factor by continuously suppressing gadd153 gene expression in growing VSMCs.

Ultrasonography of gastric volvulus: "peanut sign"

We report a case of chronic gastric volvulus in which ultrasonography (US) was useful. An 81-year-old woman was hospitalized due to vomiting, and upper gastroduodenoscopy revealed that the stomach was spirally twisted and constricted. An upper gastrointestinal barium study demonstrated an organoaxial-mesenteroaxial combined type gastric volvulus. US showed constriction between the dilated upper stomach body and the lower stomach body similar to a "peanut". Thereafter, the patient's vomiting stopped and follow-up US demonstrated that the constriction of the stomach was loosened. Therefore, we believe that this characteristic US sign paralleled the symptoms of the patient.

In vivo demonstration of alpha(1A)-adrenoceptor subtype selectivity of KMD-3213 in rat tissues

The present study was undertaken to characterize the in vivo alpha(1)-adrenoceptor binding of KMD-3213, a novel selective antagonist of alpha(1A)-adrenoceptors, in rat tissues by using a tritiated ligand with high specific activity, in comparison with that of [(3)H]prazosin. A significant degree of in vivo specific binding of [(3)H]KMD-3213 after i.v. injection of the radioligand (1. 4 nmol/kg) was seen in most rat tissues, except the cerebral cortex, spleen, and liver, which showed a little or no specific binding. There was a notable difference among tissues in the time course of specific [(3)H]KMD-3213 binding after i.v. injection of the ligand. The specific binding in the lung, kidney, and spleen was greatest at 10 min and declined rapidly with the disappearance of the ligand from the plasma. On the other hand, [(3)H]KMD-3213 binding in the submaxillary gland, vas deferens, and prostate attained peak levels at 60 min, and a considerable degree of binding was present even at 240 min. After i.v. injection of a similar dose (1.2 nmol/kg) of [(3)H]prazosin in rats, the in vivo specific binding in the submaxillary gland was greatest at 10 min and then it fell rapidly, whereas [(3)H]prazosin binding in the spleen attained a peak level at 60 min, and this was maintained even at 120 min. The AUC(0-120) values of the specific binding for [(3)H]KMD-3213, compared with those of [(3)H]prazosin, were markedly lower in the rat aorta, spleen, and liver, whereas the prostate, submaxillary gland, and lung showed significantly higher AUC(0-120) values of [(3)H]KMD-3213 compared with [(3)H]prazosin. Furthermore, the in vivo specific binding of [(3)H]KMD-3213 at dose ranges of 1.4 to 13.6 nmol/kg increased linearly in the prostate and submaxillary gland, but did not increase in a dose-dependent manner in the spleen. On the other hand, there was a dose-dependent increase in the in vivo specific binding of [(3)H]prazosin at doses of 1.2 to 10.6 nmol/kg in all tissues. The in vivo specific binding of [(3)H]KMD-3213 in rat tissues was reduced by concomitant i.v. injection of low doses of prazosin in a dose-dependent manner, but not by even a relatively high dose of yohimbine. In conclusion, the present study shows that KMD-3213 binds to the alpha(1A)-adrenoceptor subtype with a higher affinity than to the alpha(1B)- and alpha(1D)- subtypes under in vivo condition, thus leading to prostate selectivity.

Disposition and alpha(1)-adrenoceptor binding characteristics of JTH-601 and its metabolites in rat tissues

The present study was performed to characterize the disposition and alpha(1)-adrenoceptor binding of JTH-601, a novel alpha(1L)-adrenoceptor antagonist, and its metabolites (beta-D-glucopyranosyl uronic acid, JTH-601-G1; hydrogen sulfate, JTH-601-S1) in the rat prostate and other tissues. JTH-601, JTH-601-G1, and JTH-601-S1 inhibited competitively specific [(3)H]tamsulosin binding in the prostate, submaxillary gland, and spleen of rats in vitro, and the inhibitory effect of JTH-601 was 2. 5 to 6.4 times more potent than that of its metabolites. JTH-601 and its metabolites inhibited dose dependently in vivo specific [(3)H]tamsulosin binding in the particulate fraction of the prostate, aorta, submaxillary gland, and spleen of rats. Compared with that of JTH-601, the in vivo inhibitory effect of JTH-601-G1 was 1.9 to 2. 9 times more potent, and the effect of JTH-601-S1 was 1.3 to 3.2 times less potent. Based on the ratios of ID(50) values, JTH-601 and JTH-601-G1 appeared to be 4.0 to 6.9 times more selective than prazosin as far as the alpha(1)-adrenoceptors in the prostate and submaxillary gland versus the spleen or aorta were concerned. The total radioactivity in rat tissues after i.v. injection of [(3)H]JTH-601-G1 was considerably lower than that of [(3)H]JTH-601. The plasma concentration of [(3)H]JTH-601-G1 at 10 min after i.v. injection in rats was 3 times higher than that of [(3)H]JTH-601, and conversely, the concentration in the prostate was 3 times lower. Although in vivo [(3)H]JTH-601-G1 binding at 10 min was significantly lower than that of [(3)H]JTH-601 in most rat tissues, there was comparable binding between these radioligands in the prostate and vas deferens. Specific binding of [(3)H]JTH-601, at 60 min after i.v. injection compared with that at 10 min, was considerably reduced in rat tissues except the prostate and vas deferens, both of which showed relatively sustained binding. In conclusion, the present study has shown that JTH-601 and its metabolites bind to alpha(1)-adrenoceptors in rat tissues in vivo and that JTH-601-G1 retains the prostatic alpha(1)-adrenoceptor subtype selectivity of its parent compound.

Coronary spastic angina induced by anticholinesterase medication for myasthenia gravis--a case report

Myasthenia gravis (MG) is characterized by weakness of skeletal muscles because of a decrease in the number of available acetylcholine receptors at neuromuscular junctions. Anticholinesterase medication is widely used to treat MG, but muscarinic side effects sometimes appear and limit the drug usage. To their knowledge, the authors present the first case of coronary spastic angina quite possibly induced by anticholinesterase medication to treat MG. The appearance of coronary spastic angina in the present case is likely mediated through the increase of acethylcholine by anticholinesterase medication.

Troglitazone induces apoptosis via the p53 and Gadd45 pathway in vascular smooth muscle cells

Thiazolidinediones, activators of peroxisome proliferator-activated receptor (PPAR)gamma, have been reported to induce apoptosis in many types of cells. In the present study, we investigated the effects of thiazolidinediones, troglitazone, and pioglitazone on the cell growth of vascular smooth muscle cells, and identified a specific effect of troglitazone in addition to PPARgamma activation. Subconfluent rat culture vascular smooth muscle cells were treated with or without PPARgamma activators, troglitazone (1-30 microM), or pioglitazone (1-30 microM) for 72 h. After treatment, cell viability was significantly reduced by troglitazone in concentrations of 5-30 microM but not by pioglitazone. Vascular smooth muscle cells appeared to float and shrink 48 h after treatment with 20 microM of troglitazone. In situ DNA labeling showed that the nuclei of these cells were positively stained, and genomic DNA extracted from the cells showed nucleosomal laddering. Messenger RNA expression levels of c-myc, p21, bax, bcl-2, and bcl-x were not changed by the treatment with troglitazone. In contrast, along with the induction of vascular smooth muscle cell apoptosis, both the mRNA and protein expression levels of p53 and Gadd45 markedly increased in response to troglitazone. These results strongly suggest that troglitazone can induce vascular smooth muscle cell apoptosis and that this effect is caused primarily by activation of the p53 and Gadd45 pathway but not by PPARgamma activation.

Polygonum tinctorium extract suppresses nitric oxide production by activated macrophages through inhibiting inducible nitric oxide synthase expression

Despite its beneficial role in host defense mechanisms, excessive nitric oxide (NO) production by activated macrophages has been implicated in several inflammatory diseases. To clarify the mechanisms of anti-inflammatory activities of Polygonum tinctorium, we evaluated whether extracts of P. tinctorium could modulate the production of NO by activated macrophages. An AcOEt extract of P. tinctorium markedly inhibited NO synthesis by interferon-gamma (IFN-gamma)/lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages and the macrophage-like cell line RAW 264.7 in a dose-dependent manner. Inhibition of NO synthesis was achieved by reducing inducible NO synthase (iNOS) expression at protein and mRNA levels. However, the AcOEt extract of P. tinctorium failed to inhibit NO synthesis when iNOS was already expressed following stimulation with IFN-gamma and LPS. The AcOEt extract also exhibited inhibitory activity on iNOS expression in human lung epithelial A549 cells stimulated with a combination of IFN-gamma, TNF-alpha and IL-1 beta without affecting the expression of constitutive isoforms of NOS. Furthermore, in vivo injection of the AcOEt extract of P. tinctorium into LPS-treated mice significantly reduced NO synthesis by peritoneal exudate cells under ex vivo conditions. These results suggest that P. tinctorium extract may be a potential therapeutic modulator of NO synthesis in various pathological conditions.

Differential down-regulation of the human delta-opioid receptor by SNC80 and [D-Pen(2),D-Pen(5)]enkephalin

We examined the contribution of the human delta-opioid receptor carboxyl terminal tail to (+)-4-[(alphaR)-alpha-((2S,5R)-4-allyl-2, 5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide (SNC80)- and cyclic[D-Pen(2),D-Pen(5)]enkephalin (DPDPE)-mediated receptor down-regulation. Both SNC80 and DPDPE mediated down-regulation of an epitope tagged human delta-opioid receptor. Truncation of the human delta-opioid receptor after Gly(338) blocked DPDPE-mediated down-regulation. However, SNC80 mediated significant down-regulation of the truncated receptor. These findings suggest that SNC80-mediated down-regulation involves receptor domains in addition to the carboxyl terminal tail.

Giant unruptured aneurysm of the thoracic aorta--a case report

An asymptomatic 88-year-old woman underwent a screening medical examination. The chest x-ray film showed a large mediastinal mass with calcification. Both chest computed tomography and nuclear magnetic resonance imaging revealed an unruptured aortic aneurysm, predominantly affecting the ascending aorta and the proximal part of the aortic arch. Its maximum diameter was 10.5 cm. An ascending aortic aneurysm more than 10 cm in diameter is very rare. She died of acute pulmonary embolism unrelated to the aneurysm, and autopsy indicated that the etiology of the aneurysm was atherosclerotic degeneration. Retrospectively, the natural progression of the aneurysm was able to be followed on a series of chest x-ray films obtained over 18 years.

Transcriptional regulation of the platelet-derived growth factor alpha receptor gene via CCAAT/enhancer-binding protein-delta in vascular smooth muscle cells

Inflammatory cytokines stimulate the proliferation of vascular smooth muscle cells (VSMC) and play a pivotal role in the pathogenesis of vascular diseases including atherosclerosis and restenosis. Mitogenic response of interleukin-1beta (IL-1beta) on VSMC is thought to be mediated by induction of endogenous platelet-derived growth factor (PDGF), especially PDGF-AA. Although the action of PDGF-AA is mediated by its specific receptor, PDGFalpha-receptor (PDGFalphaR), very little is known about the regulatory mechanism of PDGFalphaR gene expression in VSMC. To understand the mechanism, we studied the transcriptional control of the PDGFalphaR gene in VSMC after treatment with IL-1beta. IL-1beta (10 ng/ml) drastically increased both PDGFalphaR and CCAAT/enhancer-binding protein delta (C/EBPdelta) mRNA levels in a time dependent manner. A rapid induction of C/EBPdelta mRNA within 30 min was followed by slower emergence of PDGFalphaR mRNA, which reached the maximum level in 12 h, whereas C/EBPdelta mRNA was detectable at 30 min and reached the maximum level at 3 h. Electromobility shift and supershift assays revealed that IL-1beta markedly increased DNA-protein complex, which was mainly composed of C/EBPbeta and/or -delta. Both Western blotting and immunohistochemistry demonstrated that either C/EBPbeta or -delta expression was induced by IL-1beta exclusively in nuclei of VSMC. On the other hand, overexpression of C/EBPdelta specifically transactivated the promoter activity of the PDGFalphaR gene and significantly enhanced VSMC proliferation in PDGF-treated cells. We conclude that induction of PDGFalphaR expression is mainly mediated by C/EBPdelta expression in VSMC, and a high level of C/EBPdelta expression may be involved in the pathogenesis of atherosclerosis and restenosis.

Intracellular production of interleukin-18 in human epithelial-like cell lines is enhanced by hyperosmotic stress in vitro

Interleukin-18 is a novel multifunctional cytokine, which enhances natural killer cell activity and promotes the induction of cytokine production, including that of interferon-gamma by T cells and antitumor effects. Interleukin-18 is produced by cells of several different tissues (e.g., macrophages, keratinocytes, osteoblasts, and intestinal epithelium); however, it is unclear what physiological conditions or stimuli induce interleukin-18 production. To determine physiological conditions for the production of interleukin-18, we have examined the effect of mannitol-induced hyperosmotic conditions on normal human umbilical vein endothelial cells (HUVEC) and eight established human epithelial-like cell lines (Intestine 407, Caco-2, A253, HeLa, SCC25, HT1197, ACHN, A549). Hyperosmotic conditions induced interleukin-18 immunoreactivity in all the human cell lines tested, as detected by immunocytochemistry. The enhanced interleukin-18 production was also observed when mannitol was replaced with NaCl as the inducer of hyperosmotic stress. Enzyme-linked immunosorbent assays revealed that interleukin-18 concentrations in cell extracts were significantly increased by hyperosmotic conditions. Reporter gene assays also revealed that hyperosmotic conditions stimulated transcriptional activity of the interleukin-18 promoter. These results show for the first time that hyperosmotic stress is a stimulator of interleukin-18 production in epithelial-like cells.

The unique 5-flanking region of the human basic calponin gene

Calponin has been implicated in the regulation of smooth muscle contraction. Basic calponin, one of the calponin isoforms, is expressed exclusively in smooth muscle cell (SMC)-rich tissues, and is considered to be a phenotypic marker of differentiated SMC. To define the molecular mechanism of SMC-specific gene transcription in humans, we isolated and characterized the 5'-flanking region of this gene. Sequence analysis revealed that several putative cis-acting elements were clustered within a 500-bp sequence upstream of the transcription start site. However, the 1.9-kb promoter region obtained herein lacked a completely matched consensus sequence of the CArG box that is commonly identified in the promoter region of other SMC-specific genes. A luciferase assay demonstrated that the 1.9-kb promoter region was sufficient to drive a basal transcriptional activity not only in human vascular smooth muscle cells (VSMC) but also in HeLa cells. In particular, the sequence between positions -1,906 and -867 had a significantly higher transcriptional activity in VSMC than in HeLa cells. In contrast, the promoter activity was drastically decreased between positions -327 and -257 in both types of cells. These results indicate that the sequence spanning from position -327 to -257 contains an essential domain involved in the basal transcriptional activity of the human basic calponin gene, and that the distal region of the 1.9-kb 5'-flanking sequence presented herein may play a pivotal role in the phenotypic modulation of VSMC.

Apoptosis and Bcl-xs in the intimal thickening of balloon-injured carotid arteries

We performed balloon injury in the rat carotid artery and identified intimal thickening after injury. Balloon-injured carotid arteries showed maximum thickness of the neointima on the 14th day before complete endothelial cell regeneration. In this lesion we identified apoptosis of vascular smooth muscle cells (VSMCs) by in situ DNA labelling and electron microscopy in the neointima on the 14th day after injury. mRNA expression levels of bcl-2, bax, bcl-x, p53 and caspase-1 were determined by the reverse transcriptase-polymerase chain reaction method both in injured and uninjured carotid arteries. Neither bcl-2 nor bcl-xl mRNA expression was detected in either injured or uninjured arteries, whereas bax and p53 mRNA expression was identified and their mRNA levels were not altered after balloon injury. In contrast, both bcl-xs and caspase-1 mRNA was detected and was markedly induced only in the injured carotid artery. Positive staining for immunoreactive Bcl-x was observed specifically in the injured arterial wall and co-localized with positive staining of nuclei identified by in situ DNA labelling. We conclude that two opposite cellular responses, VSMC proliferation and apoptosis, exist together in the neointima of the rat carotid artery after balloon injury, and selective induction of Bcl-xs expression is a key regulator of VSMC apoptosis in the process of vascular remodelling.

Novel cis element for tissue-specific transcription of rat platelet-derived growth factor beta-receptor gene

Platelet-derived growth factor (PDGF) and its receptors are widely expressed in several tissues in the stage of cellular growth and development. In adulthood, PDGF beta-receptor (PDGFbetaR) is mainly detected in pathological conditions such as atherosclerotic lesions and injured vascular wall. The purpose of the present study was to elucidate the underlying mechanism of PDGFbetaR gene expression under pathological conditions in vascular smooth muscle cells (VSMC) and to identify the important cis elements responsible for tissue-specific gene transcription. Gel mobility shift assay and supershift assay indicated that the CCAAT motif located at -67 (C67) was mainly interacted with NF-YC, and this element drove the basal promoter activity of the gene as a putative promoter. On the other hand, another important sequence essential for the basal transcription was found at a 30-bp region (R30) spanning -150 to -121. To test whether R30 actually regulates the tissue-specific transcription of PDGFbetaR gene, electromobility shift pattern was compared between VSMC and hepatoma cell line (HTC). We obtained the result that DNA-protein complex seen only in nuclear extracts from HTC suppressed the promoter activity in HTC in a tissue-specific manner. Furthermore, cis element decoy transfection experiments for C67 and R30 also revealed that both elements were functionally important in mRNA expression of PDGFbetaR in VSMC. From these results, we concluded that the basal activity of PDGFbetaR gene expression was transactivated by the interaction or coordination of both C67 and R30, and the latter one mainly controlled the tissue-specific gene expression in VSMC.

Postprandial hypotension is associated with asymptomatic cerebrovascular damage in essential hypertensive patients

offelucidate the relationship between postprandial hypotension (PPH) and asymptomatic cerebrovascular damage, we evaluated changes in blood pressure after a meal by 24-hour blood pressure monitoring in 70 hospitalized essential hypertensive patients aged >/=50 years. They received a diet containing standard nutritional ingredients with 120 mmol (7 g) NaCl and were free from medication for at least 1 week. PPH was defined as the mean reduction of systolic blood pressure during 2 hours after a meal. Patients were divided into three groups according to mean values of PPH after 3 meals: PPH-1 (n=16, 5 mm Hg</=PPH<10 mm Hg), PPH-2 (n=18, PPH>/=10 mm Hg), and normal (n=36, PPH<5 mm Hg). As asymptomatic cerebrovascular damage, lacunae and leukoaraiosis were evaluated by magnetic resonance imaging. PPH did not correlate with daytime or nighttime blood pressure or the nondipper phenomenon; however, PPH was significantly related to asymptomatic cerebrovascular damage. The prevalence of lacunae in the normal, PPH-1, and PPH-2 groups was 44%, 69%, and 83%, respectively (chi2=8.22, P<0.05). The number of lacunae in the normal, PPH-1, and PPH-2 groups was 1.0+/-1.3, 1.3+/-1.2, and 1. 9+/-1.4, respectively (F[2,67]=3.2, P<0.05). The prevalence of advanced leukoaraiosis in the normal, PPH-1, and PPH-2 groups was 44%, 50%, and 83%, respectively (chi2=7.63, P<0.05). Severity score of leukoaraiosis in the normal, PPH-1, and PPH-2 groups was 1.5+/-0. 7, 1.7+/-0.8, and 2.1+/-0.7, respectively (F[2,67]=4.3, P<0.05). These findings indicate that elderly hypertensive patients with marked PPH should be considered to have advanced cerebrovascular damage even in the absence of abnormal neurological findings.

Cloning and expression of a single-chain Fv fragment specific for the human interleukin 18 receptor

We have recently reported the successful purification and characterization of the human interleukin 18 (IL-18) receptor (R) using a monoclonal antibody (MAb) of the IgM kappa class (117-10C) after immunizing mice with cells of the Hodgkin's disease-derived cell line L428. This antibody is specific for the human IL-18R and inhibits the bioactivity of IL-18. Here we report on the polymerase chain reaction (PCR)-assisted cloning and sequencing of cDNAs encoding the variable regions of the light and heavy chains of 117-10C. We expressed the antibody in the form of a single-chain Fv fragment (scFv) in Chinese Hamster Ovary (CHO) cells and purified it from culture supernatants by chromatography. The purified scFv has an affinity for IL-18R of 5.6 x 10(8) M(-1), whereas 117-10C binds to the receptor with an affinity constant of 3.6 x 10(9) M(-1). Since 117-10C is of the IgM class, it is expected to be in the pentamer form and should theoretically therefore bind IL-18R with 10 times the affinity of the single-chain fragment may explain the difference in the affinity constants for the two molecules. The inhibitory efficiency of 117-10C was found to be 6-fold that of scFv in an interferon gamma (IFN-gamma)-inducing assay on the IL-18-responsive cell line KG-1. In conclusion, we have produced a single-chain fragment of a murine anti-human IL-18R antibody that is as potent at binding IL-18 as the parent antibody, and may be useful in neutralizing the cytokine in human conditions associated with high production of IL-18.

Two factors of experienced deficits in schizophrenia and their relationships with positive, negative, and depressive symptoms

Eighty inpatients and 20 outpatients with ICD-10 schizophrenia were assessed with the Manchester Scale (MS) and the scale for the assessment of Subjective Experience of Deficits in Schizophrenia (SEDS). A factor analysis on MS scores yielded a three-factor solution: negative symptoms, positive symptoms, and anxious-depressive factor. On the other hand, a factor analysis on SEDS scores provided a seven-factor solution. The first factor, "awareness of social incompetence (ASI)," positively correlated with the anxious-depressive factor. ASI may reflect a negative cognitive attitude of persons who easily become depressive. The second factor, "subjective cognitive disturbance (SCD)," positively correlated with the positive-symptoms factor. SCD might represent a subtle disturbance, which can also produce positive symptoms. We found no factor on SEDS that correlated with the negative-symptoms factor. It was noted that a selection and comparison of items and the cultural background of subjects should be considered.

Postprandial hypotension: evaluation by ambulatory blood pressure monitoring

To elucidate whether postprandial hypotension (PPH) is associated with any diurnal change of blood pressure, ambulatory blood pressure monitoring was performed on 121 hospitalized essential hypertensive patients who received standardized meals. Postprandial change in blood pressure was defined as the difference between mean systolic blood pressure (SBP) 1 h before and 2 h after each meal. The postprandial decline of SBP showed age-dependent augmentation. The degree of PPH was significantly related to the level of preprandial blood pressure for each meal. Patients were divided into the following three groups according to the mean PPH of three meals: Normal group (n = 79); mean postprandial decline of SBP <5 mm Hg, PPH-1 group (n = 24); 5 mm Hg ' mean PPH < 10 mm Hg, and PPH-2 group (n = 18); PPH 2 > or = 10 mm Hg. There was no difference in 24-h, nighttime, or daytime blood pressure among the three groups. The prevalence of dipper and nondipper patients was not different among the three groups. However, patients in PPH-2 showed significantly greater daytime and 24-h blood pressure variability. Furthermore, there was a significant positive relationship between the morning surge of SBP and PPH after breakfast (r = 0.36, P < .001). These findings indicate that PPH increases blood pressure variability independently of nocturnal change in blood pressure.

Constitutive and induced IL-18 receptor expression by various peripheral blood cell subsets as determined by anti-hIL-18R monoclonal antibody

Interleukin-18 (IL-18) was identified as a molecule that induces IFN-gamma production and enhances NK cell cytotoxicity. Characterization of the receptor for human IL-18 (hIL-18R) is important for investigating the physiological role of IL-18 in nature. In the present study, we describe a monoclonal antibody (mAb) against hIL-18R (mAb No. 117-10C). This mAb inhibited the binding of 125I-labeled hIL-18 to IL-18R-expressing L428 cells. This mAb also neutralized hIL-18-induced T helper 1 type cytokine (IFN-gamma and GM-CSF) production by Con A-stimulated PBMC. PBMC were examined for the expression of IL-18R by two-color flow cytometry. Most CD19(+) B cells and a percentage of CD8(+) T cells were found to constitutively express IL-18R. Treatment of PBMC with IL-12 preferentially induced IL-18R expression on CD56(+) NK cells regardless of costimulation with mitogen. IL-18R expression on CD4(+) T cells was induced weakly by IL-12 treatment and moderately by PHA stimulation. However, neither could IL-12 treatment nor PHA stimulation induce IL-18R expression on CD8(+) T cells. Costimulation with both IL-12 and PHA was necessary for optimal IL-18R expression on CD8(+) T cells as well as on CD56(+) NK cells, CD4(+) T cells, and CD19(+) B cells. These results support the growing number of reports showing that IL-18 has modulatory effects on T, B, and NK cells.

Establishment of the cells useful for murine interleukin-18 bioassay by introducing murine interleukin-18 receptor cDNA into human myelomonocytic KG-1 cells

We genetically engineered human myelomonocytic KG-I cells by introducing cDNA of murine interleukin-18 receptor (MuIL-18R) and established human cells which were capable of responding to MuIL-18. These cells expressed larger number of MuIL-18R (> 13,000 sites/cell) than intrinsic human IL-18 receptor (HuIL-18R) (< 2,500 sites/cell). And the cells responded to MuIL-18 as well as to HuIL-18 in a dose-dependent manner, and produced large amounts of interferon-gamma (IFN-gamma). We could estimate the amount of murine IL-18 based on the amounts of IFN-gamma produced by these cells. The stoichiometry was observed up to 150 ng/ml of MuIL-18. By using these cells, a large amount of MuIL-18 (448 +/- 89.2 ng/ml) was detected in sera of Propionibacterium acnes (P. acnes)/lipopolysaccharide (LPS)-treated endotoxic mice (the same conditions in which IL-18 was first identified). These cells provide us with a useful tool for determining the bioactivity of MuIL-18.

Platelet-derived growth factor induces apoptosis in vascular smooth muscle cells: roles of the Bcl-2 family

Apoptosis (programmed cell death) is observed in vascular smooth muscle cells (VSMC) in atherosclerotic lesions and stenotic lesions after injury, and modulates the cellularity of these lesions. It is recognized that cell growth and apoptosis are two linked processes. Platelet-derived growth factor (PDGF) induces VSMC proliferation and migration in vitro. We studied the effect of PDGF on apoptosis in VSMC. Cultured rat VSMC were treated with PDGF-AA or PDGF-BB. PDGF-BB induced cell death in cultured VSMC in a time- and dose-dependent manner, but PDGF-AA did not. Gel electrophoresis of genomic DNA and in situ DNA labeling confirmed that the cell death induced by PDGF-BB is apoptosis. PDGF-BB treatment reduced bcl-2 mRNA and bcl-xl mRNA expression, in contrast, induced bcl-xs mRNA expression, linked with the induction of apoptosis in cultured VSMC.

Endoscopic transthoracic sympathectomy with a fine (2-mm) thoracoscope in palmar hyperhidrosis: a case report

Endoscopic transthoracic sympathectomy (ETS) is a minimally invasive method, causing only small injuries and few complications, and requires only a short period of hospitalization. Therefore, this method has been applied to patients with palmar hyperhidrosis to whom the conventional transthoracic sympathectomy, which is much more invasive, or thoracic sympathetic blockade, which often causes complications, cannot be applied. Conventional thoracoscopes, such as a resectoscope 8 mm in diameter for urological operations, or a thoracoscope 5 mm in diameter, were usually used for this purpose, but they cause operative injuries. We performed ETS using a thoracoscope 2 mm in diameter (MiniSite 2 mm 0 degrees, USSC171303). Its visual field and handling were not inferior to those of conventional thoracoscopes, and the operative injuries were only 2 mm in size. For the patient, a small scar of this size means virtually no scar.

Molecular structure and function of rat platelet-derived growth factor beta-receptor gene promoter

OBJECTIVE

To understand the regulatory mechanism of platelet-derived growth factor beta-receptor gene expression.

METHODS

A 1.7 kb genomic fragment was obtained from a rat genomic library. After we had determined an entire sequence of this fragment, transcription start sites were determined both by primer extension analysis and by riboprobe mapping. We performed a functional promoter assay by using a dual-luciferase reporter system. Progressive 5'-deletions of the fragment and site-directed mutagenesis for the CCAAT motif located at -67 or -94 were used for the assay, and their promoter activities in vascular smooth muscle cells were assessed. Gel-mobility shift analysis was also performed for the CCAAT motif at -67. Effects of the upstream sequence spanning -310 through -120 on heterologous gene promoters were also investigated.

RESULTS

Multiple transcription start sites were observed in the 5'-flanking region, and the 1.7 kb sequence was actually active as a functional promoter in vascular smooth muscle cells. Two important sequences responsible for the basal transcriptional activity were identified by the functional promoter assay. One was the CCAAT motif at -67 which acts as a promoter itself, and the other was the upstream region spanning -310 through -210 which positively regulates the basal promoter activity.

CONCLUSION

The basal promoter activity of the rat platelet-derived growth factor beta-receptor gene is mainly regulated by the interaction or coordination of two sequences, the CCAAT motif and the upstream control element.

[An elderly patient with bleeding from the alimentary tract caused by aberrant pancreas of the small intestine]

A 71-year-old woman was admitted to hospital because of malaise and bloody stool. Laboratory findings consistently showed anemia (Hb 9.2 g/dl) and occult blood in the stool. Although barium series and endoscopy of the upper and lower intestinal tructs were carried out, there was no evidence of bleeding from the gastrointestinal tract 99mTcO4- scintigraphy, which was performed to exclude bleeding from Meckel's diverticulum, also did not locate a significant lesion. Angiographic imaging of the superior mesenteric arteries (SMA) was performed to exclude lesions such as small intestine tumors with extraluminal growth and vascular abnormalities such as A-V malformation and it revealed the round encasement of arteries in the peripheral SMA region, strongly suggestive of a small intestine tumor. Surgery was performed and an extraluminally protruding tumor was found in the small intestine. The excised tumor was 4 x 3 x 3.5 cm in size, are was diagnosed histologically as aberrant pancreas. The postoperative laboratory findings showed that the anemia had improved and occult blood was not detected in the stools. Although aberrant pancreas of the small intestine is a common benign tumor, it is a very unusual cause of bleeding from the alimentary tract.

Involvement of caspase-1 and caspase-3 in the production and processing of mature human interleukin 18 in monocytic THP.1 cells

Recently, human interleukin 18 (hIL-18) cDNA was cloned, and the recombinant protein with a tentatively assigned NH2-terminal amino acid sequence was generated. However, natural hIL-18 has not yet been isolated, and its cellular processing is therefore still unclear. To clarify this, we purified natural hIL-18 from the cytosolic extract of monocytic THP.1 cells. Natural hIL-18 exhibited a molecular mass of 18.2 kDa, and the NH2-terminal amino acid was Tyr37. Biological activities of the purified protein were identical to those of recombinant hIL-18 with respect to the enhancement of natural killer cell cytotoxicity and interferon-gamma production by human peripheral blood mononuclear cells. We also found two precursor hIL-18 (prohIL-18)-processing activities in the cytosol of THP.1 cells. These activities were blocked separately by the caspase inhibitors Ac-YVAD-CHO and Ac-DEVD-CHO. Further analyses of the partially purified enzymes revealed that one is caspase-1, which cleaves prohIL-18 at the Asp36-Tyr37 site to generate the mature hIL-18, and the other is caspase-3, which cleaves both precursor and mature hIL-18 at Asp71-Ser72 and Asp76-Asn77 to generate biologically inactive products. These results suggest that the production and processing of natural hIL-18 are regulated by two processing enzymes, caspase-1 and caspase-3, in THP.1 cells.

Purification and characterization of the human interleukin-18 receptor

Interleukin (IL)-18 was identified as a molecule that induces IFN-gamma production and enhances NK cell cytotoxicity. In this paper, we report upon the purification and characterization of human IL-18 receptor (hIL-18R). We selected the Hodgkin's disease cell line, L428, as the most strongly hIL-18R-expressing cell line based on the results of binding assays. This binding was inhibited by IL-18 but not by IL-1beta. The dissociation constant (Kd) of 125I-IL-18 binding to L428 cells was about 18.5 nM, with 18,000 binding sites/cell. After immunizing mice with L428 cells and cloning, a single monoclonal antibody (mAb) against hIL-18R was obtained (mAb 117-10C). Sequentially, hIL-18R was purified from 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid (CHAPS)-extracted L428 cells by wheat germ lectin-Sepharose 4B chromatography and mAb 117-10C-Sepharose chromatography. The internal amino acid sequences of hIL-18R all matched those of human IL-1 receptor-related protein (IL-1Rrp), the ligand of which was unknown to date. When expressed in COS-1 cells, the cDNA of IL-1Rrp conferred IL-18 binding properties on the cells and the capacity for signal transduction. From these results, we conclude that a functional IL-18 receptor component is IL-1Rrp.

Asymptomatic cerebrovascular damages in essential hypertension in the elderly

To investigate the underlying mechanisms of asymptomatic cerebrovascular damage, the diurnal change in blood pressure was evaluated in hypertensive patients with silent cerebral infarction (SCI). Sixty elderly hypertensive patients (age > or = 60 years) were matched with 40 middle-aged patients (age < or = 59 years) for sex and left ventricular mass index (LVMi). Lacunar lesions were evaluated by magnetic resonance imaging as SCI. The presence and the severity of SCI increased with age. In the middle-aged group, the presence of SCI was significantly related to 24-h blood pressure and LVMi evaluated by echocardiography. In elderly patients, the presence of SCI had no relationship with 24-h blood pressure or LVMi. The lowest level of nocturnal diastolic blood pressure showed a J-shaped relationship with the incidence of SCI in the elderly patients. These findings indicate that the hemodynamic characteristics underlying the development of SCI differ between middle-aged and elderly hypertensive patients. A different approach to the treatment of hypertension in the elderly appears necessary.

[Mollaret meningitis associated with a high level of cytokines in cerebrospinal fluid]

A 70-year-old man was admitted to our hospital for further evaluation of recurrent fever, which had begun in October 1994. The patient had 5 to 7 days without fever, and then 2 to 3 days of fever. He had headaches during the febrile periods. On admission, he had abnormal pyramidal, extrapyramidal, and celebellar signs, and nuchal rigidity during the febrile period. However, these neurological abnormalities were completely absent during the afebrile period. Examination of cerebrospinal fluid revealed pleocytosis of mononuclear cells. During the febrile period, pleocytosis was associated with high levels of IgG, IL-6, TNF-alpha, and PGE2 in the cerebrospinal fluid. Administration of indomethacin prevented the fever, which suggests that abnormal production of cytokines in the cerebrospinal fluid contributes to fever in Mollaret meningitis.

Protection against Fas/APO-1- and tumor necrosis factor-mediated cell death by a novel protein, sentrin

Fas/APO-1 and TNF receptor 1 share a common signaling motif in their cytoplasmic tail called the "death domain." Using the death domain as bait in the yeast two-hybrid system, several death domain-containing proteins that participate in cell death signaling have been identified. Here we report the isolation of a novel protein, sentrin, which interacts with Fas/APO-1 and TNF receptor 1 but not with FADD/MORT1 or CD40. Two-hybrid interaction assays reveal that sentrin associates only with the signal-competent forms of Fas/APO-1 or TNF receptor 1 death domains. Sentrin is a novel protein of 101 amino acids with homology to ubiquitin, Nedd8, and a Saccharomyces cerevisiae protein, Smt3. When overexpressed, sentrin provides protection against both anti-Fas/APO-1 and TNF-induced cell death.

Protection against Fas/APO-1- and tumor necrosis factor-mediated cell death by a novel protein, sentrin

Fas/APO-1 and TNF receptor 1 share a common signaling motif in their cytoplasmic tail called the "death domain." Using the death domain as bait in the yeast two-hybrid system, several death domain-containing proteins that participate in cell death signaling have been identified. Here we report the isolation of a novel protein, sentrin, which interacts with Fas/APO-1 and TNF receptor 1 but not with FADD/MORT1 or CD40. Two-hybrid interaction assays reveal that sentrin associates only with the signal-competent forms of Fas/APO-1 or TNF receptor 1 death domains. Sentrin is a novel protein of 101 amino acids with homology to ubiquitin, Nedd8, and a Saccharomyces cerevisiae protein, Smt3. When overexpressed, sentrin provides protection against both anti-Fas/APO-1 and TNF-induced cell death.

Pneumatization of the tympanic bulla after blockage of the ventilation route through the eustachian tube in the pig

To examine whether gas exchange occurs in the middle ear air cell system independent of the eustachian tube (ET), we occluded the middle ear clefts of piglets, whose tympanic bullae closely resemble the human mastoid air cell system, and investigated subsequent changes in the air cell system. We anticipated that pneumatization and development of the air cell system would continue if gas were exchanged through the mucosa lining the air cell system. If, on the other hand, mastoid air cells depend on the ET, mastoid development would be impaired or arrested. In noninflamed ears, pneumatization was maintained, and development of the air cell system continued after the middle ear cleft had been occluded with an acrylate adhesive and the bullar air cell system was thus excluded from any communication with the ET. These results indicate that the normal middle ear air cell system has the capacity to perform gas exchange independently of the ET, with gas exchange appearing to occur through the submucosal capillary network.

Tissue-specific molecular heterogeneity of human growth hormone-releasing hormone receptor protein

A site-directed anti-peptide antibody (anti-hGHRHRc18) was generated against the cytoplasmic tail of human GHRH receptor. The dissociation constant (Kd) and the antibody binding site (AbT) of anti-hGHRHRc18 were 2.5 nmol/l and 0.54 nmol/l, respectively. In an immunoblotting experiment, affinity-purified anti-hGHRHRc18 specifically recognized a single 50-kDa protein in human pituitary. In a screening of the expression of GHRH receptor protein in extra-pituitary tissues, only human kidney showed a single 52-kDa protein. Our results suggest that the GHRH receptor protein exhibits tissue-specific molecular heterogeneity.

Angiotensin-converting enzyme gene polymorphism in essential hypertensive patients in Japanese population

Association between angiotensin-converting enzyme (ACE) gene polymorphism and essential hypertension in a Japanese population with the same socioeconomic background was investigated. Insertion-deletion (I/D) polymorphism of the ACE gene located on intron 16 was detected by polymerase chain reaction. Association between ACE gene polymorphism and family history of essential hypertension as well as the development of vascular damage in eye fundi were also investigated. Variation at ACE loci did not contribute to essential hypertension and the vascular damages in eye fundi. These results suggest that the ACE gene was not directly responsible for essential hypertension in this particular Japanese population with the same socioeconomic background.

Tympanic bulla pneumatization following experimental mastoidectomy in a porcine animal model

The effect of mastoidectomy on mastoid pneumatization was investigated in an animal model. Experimental mastoidectomy was performed on the air cell system of the tympanic bullae in 10 four-week-old piglets. The developmental process of this structure is very similar to that of the human mastoid air cell system. Two piglets each were decapitated at 1 and 2 weeks, and 1, 3 and 5 months after the operation, and hematoxylin and eosin sections of the bullae were examined histopathologically. The development of the tympanic bulla itself was not affected by the operation. However, inside the bulla, a great amount of bone tissue had proliferated peripheral to the surgical cavity without new formation of normal pneumatized cells. When mastoidectomy was performed in the course of the pneumatization, subsequent pneumatization did not occur in this animal model. This result suggests that mastoidectomy in childhood may arrest the new formation of mastoid air cells in humans.

Cloning of the cDNA for human IFN-gamma-inducing factor, expression in Escherichia coli, and studies on the biologic activities of the protein

We have recently reported that a novel molecule, murine IFN-gamma-inducing factor (IGIF) produced by mouse liver cells, possesses potent biologic activities, including the induction of IFN-gamma production by spleen cells and the enhancement of NK cell cytotoxicity. In this paper, we report on the isolation of human IGIF cDNA clones from normal human liver cDNA libraries using murine IGIF cDNA as a probe. The amino acid sequence deduced from the human cDNA clones indicated a 193-amino acid precursor peptide and revealed 65% homology with that of murine IGIF. The amino acid sequence of IGIF also included an IL-1 signature-like sequence. Subsequently, the cloned cDNA was expressed in Escherichia coli, and preliminary studies on the biologic activities of the recombinant protein were performed. The recombinant human IGIF induced IFN-gamma production by mitogen-stimulated PBMC and enhanced NK cell cytotoxicity, in a manner similar to murine IGIF. In addition, recombinant human IGIF also augmented granulocyte-macrophage-CSF production and decreased IL-10 production, but had no effect on IL-4 production by Con A-stimulated PBMC. Based on these pleiotropic effects of IGIF, we propose that this novel cytokine be designated as IL-18.

Cloning of the cDNA for human IFN-gamma-inducing factor, expression in Escherichia coli, and studies on the biologic activities of the protein

We have recently reported that a novel molecule, murine IFN-gamma-inducing factor (IGIF) produced by mouse liver cells, possesses potent biologic activities, including the induction of IFN-gamma production by spleen cells and the enhancement of NK cell cytotoxicity. In this paper, we report on the isolation of human IGIF cDNA clones from normal human liver cDNA libraries using murine IGIF cDNA as a probe. The amino acid sequence deduced from the human cDNA clones indicated a 193-amino acid precursor peptide and revealed 65% homology with that of murine IGIF. The amino acid sequence of IGIF also included an IL-1 signature-like sequence. Subsequently, the cloned cDNA was expressed in Escherichia coli, and preliminary studies on the biologic activities of the recombinant protein were performed. The recombinant human IGIF induced IFN-gamma production by mitogen-stimulated PBMC and enhanced NK cell cytotoxicity, in a manner similar to murine IGIF. In addition, recombinant human IGIF also augmented granulocyte-macrophage-CSF production and decreased IL-10 production, but had no effect on IL-4 production by Con A-stimulated PBMC. Based on these pleiotropic effects of IGIF, we propose that this novel cytokine be designated as IL-18.

[Twenty-one cases of malignant tumor of the external auditory canal or middle ear]

Between 1982 and 1994, 21 patients with malignant tumors of the external auditory canal and middle ear were treated at the Department of Otolaryngology, Niigata University. Eleven patients with tumors of the external auditory canal and 10 tumors of the middle ear were registered. There were 9 males and 12 females, and their ages ranged from 10 to 80 years (median: 61). Otalgia, otorrhea or bloody otorrhea were the chief complaints of most patients with external auditory canal of middle ear tumors. Pathological examination revealed squamous cell carcinoma in 16 patients, adenoid cystic carcinoma in 3 patients, and basal cell carcinoma and rhabdomyosarcoma in 1 patient each. External auditory canal tumors were surgically excised, while radical mastoidectomy and subsequent irradiation were performed for the middle ear tumors. The five-year survival rate determined by the Kaplan-Meier method, was 77.8% for patients with external auditory canal tumors and 40% for those with middle ear tumors.

Cloning of a new cytokine that induces IFN-gamma production by T cells

The mechanism underlying the differentiation of CD4+ T cells into functionally distinct subsets (Th1 and Th2) is incompletely understood, and hitherto unidentified cytokines may be required for the functional maturation of these cells. Here we report the cloning of a recently identified IFN-gamma-inducing factor (IGIF) that augments natural killer (NK) activity in spleen cells. The gene encodes a precursor protein of 192 amino acids and a mature protein of 157 amino acids, which have no obvious similarities to any peptide in the databases. Messenger RNAs for IGIF and interleukin-12 (IL-12) are readily detected in Kupffer cells and activated macrophages. Recombinant IGIF induces IFN-gamma more potently than does IL-12, apparently through a separate pathway. Administration of anti-IGIF antibodies prevents liver damage in mice inoculated with Propionibacterium acnes and challenged with lipopolysaccharide, which induces toxic shock. IGIF may be involved in the development of Th1 cells and also in mechanisms of tissue injury in inflammatory reactions.

A novel costimulatory factor for gamma interferon induction found in the livers of mice causes endotoxic shock

Administration of monoclonal anti-CD3 antibody to mice treated with Propionibacterium acnes induced secretion of a high level of gamma interferon (IFN-gamma) into the circulation system, while it induced no significant release in untreated mice. In order to analyze this high-level induction of IFN-gamma in these bacterium-treated mice, we investigated the factors that might be involved. An activity that induces IFN-gamma in T cells was observed in the liver extracts of mice treated with P. acnes and subsequently challenged with lipopolysaccharide. Here, we purified an IFN-gamma-inducing factor from the liver extract to homogeneity and characterized it. Its molecular mass was 18 to 19 kDa, and its pI was 4.9. The amino acid sequence of the NH2-terminal portion was determined and shown to have no similarities to any protein in the EMBL, GenBank, and PIR data bases. The same molecule was also demonstrated in the serum factor that was previously reported to have an IFN-gamma-inducing activity and to have an apparent molecular mass of 75 kDa. Moreover, the activity of this serum factor was recovered in the fraction containing the 18- to 19-kDa protein under reducing conditions and was shown to have the same NH2-terminal amino acid sequence as that of the factor from the liver extract. In addition to the ability to induce IFN-gamma, this protein augmented T-cell proliferation and NK activity in the spleen cells. Thus, several of its biological activities were apparently similar to those of interleukin-12. These results indicated that this novel protein, which exhibited marked costimulatory activity on IFN-gamma production in vitro, was elevated vivo in response to P. acnes treatment. This factor, probably released from the producing cells by lipopolysaccharide stimuli, may be involved in the high-level induction of IFN-gamma in the P. acnes-treated mice.