Reduced inspiratory flow attenuates IL-8 release and MAPK activation of lung overstretch.

Lung overstretch involves mechanical factors, including large tidal volumes (VT), which induce inflammatory responses. The current authors hypothesised that inspiratory flow contributes to ventilator-induced inflammation. Buffer-perfused rabbit lungs were ventilated for 2 h with 21%, O2+5%, CO2, positive end-expiratory pressure of 2-3 cmH2O and randomly assigned to either: 1) normal VT (6 mL x kg(-1)) at respiratory rate (RR) 30, inspiration:expiration time ratio (I:E) 1:1, low inspiratory flow 6 mL x kg(-1) x s(-1); 2) large VT (12 mL x kg(-1)) at RR 30, I:E 1:1, high inspiratory flow 12 mL x kg(-1) x s(-1) (HRHF); 3) large VT at RR 15, I:E 1:1, low inspiratory flow 6 mL x kg(-1) x s(-1) (LRLF); or 4) large VT at RR 15, I:E 1:2.3, high inspiratory flow 10 mL x kg(-1) x s(-1) (LRHF). Physiological parameters, tumour necrosis factor (TNF)-alpha, interleukin (IL)-8 and activation of mitogen-activated protein kinases (extracellular signal-regulated kinase (ERK)1/2, p38 and stress-activated protein kinase (SAPK)/ c-Jun N-terminal kinase (JNK)) were measured. HRHF increased weight gain, perfusate IL-8 and phosphorylation of ERK1/2, p38 and SAPK/JNK. These responses were absent during LRLF but present during LRHF. Changes in TNF-alpha were small. Tissue IL-8 and phospho-ERK1/2 staining was localised primarily to smooth muscle, adventitia and bronchial epithelium within larger bronchioles and arterioles. These results indicate that mild overstretch of perfused lungs during high inspiratory flow enhances inflammatory signalling by cells in lung regions most affected by strong turbulent airflow.

3-D magnetic measurement of neuromagnetic response of somatosensory area to different repetition frequencies.

3-D magnetic measurements of the bilateral somatosensory evoked fields (SEFs) by electric stimulus to the right thumb for four normal subjects were carried out, using a three-dimensional (3-D) second-order gradiometer connected to 39-channel SQUIDs, which can detect magnetic field components perpendicular to the scalp (Br) and tangential to the scalp (Btheta, Bphi) simultaneously. To discuss the relationship between the phase lag and stimulus repetition frequency (SRF), the delay times of a component synchronous with the SRFs (1.99 to 27.02 Hz) were calculated by the convolution of the reference signal and the SEF wave (BPF: 15-40 Hz). The phase lag characteristic to the SRF in the contralateral hemisphere to the stimulus was linear in the ranges below 8 Hz and above 8 Hz in all magnetic components. The phase lag characteristic of the ipsilateral hemisphere to the stimulus was linear in only below-8 Hz in all components. It was tested for significance of the linear regression slope (beta not = 0, P<0.05).

The metastasis suppressor gene KiSS-1 encodes kisspeptins, the natural ligands of the orphan G protein-coupled receptor GPR54.

Natural peptides displaying agonist activity on the orphan G protein-coupled receptor GPR54 were isolated from human placenta. These 54-, 14,- and 13-amino acid peptides, with a common RF-amide C terminus, derive from the product of KiSS-1, a metastasis suppressor gene for melanoma cells, and were therefore designated kisspeptins. They bound with low nanomolar affinities to rat and human GPR54 expressed in Chinese hamster ovary K1 cells and stimulated PIP(2) hydrolysis, Ca(2+) mobilization, arachidonic acid release, ERK1/2 and p38 MAP kinase phosphorylation, and stress fiber formation but inhibited cell proliferation. Human GPR54 was highly expressed in placenta, pituitary, pancreas, and spinal cord, suggesting a role in the regulation of endocrine function. Stimulation of oxytocin secretion after kisspeptin administration to rats confirmed this hypothesis.

Altered growth response to prostaglandin E2 and its receptor signaling in mesangial cells from stroke-prone spontaneously hypertensive rats.

OBJECTIVE: Prostaglandin (PG) E2, a major arachidonic acid metabolite in the kidney, acts on four receptor subtypes (EP1, EP2, EP3 and EP4). One of major causes of end-stage renal failure is hypertensive renal disease, in which enhanced renal PGE2 production has been shown. In this study, to explore the pathophysiological significance of EP subtypes in the kidney, we examined the role of EP subtypes on proliferation of mesangial cells (MCs) from stroke-prone spontaneously hypertensive rats (SHRSPs), which show faster growth than those from normotensive Wistar-Kyoto rats (WKYs). DESIGN AND METHODS: Using MCs from SHRSPs and WKYs, we investigated DNA synthesis and its upstream event, the phosphorylation of extracellular signal-regulated kinase (ERK), together with the gene expression of EP subtypes. RESULTS: Sulprostone, an EP1 agonist, dose-dependently increased DNA synthesis and the phosphorylation of ERK in MCs from both strains. The EP4 agonist, 11-deoxy-PGE1, inhibited sulprostone-induced phosphorylation of ERK in WKY-MCs. In contrast, 11-deoxy-PGE1 failed to inhibit the ERK activity in SHRSP-MCs. Interestingly, cAMP production mediated by EP4 was markedly attenuated in SHRSP-MCs as compared with that in WKY-MCs, despite the overproduction of endogenous PGE2 in SHRSP-MCs. Similar gene expressions of EP1 and EP4 and only faint expression of EP3 were detected in MCs from both strains. CONCLUSIONS: These results indicate that the PGE2/EP4 system counteracts the PGE2/EP1 system at the level of the intracellular signaling pathway. The altered EP4 signaling may play a critical role in the exaggerated mesangial growth in SHRSPs.

New bronchoscopic microsample probe to measure the biochemical constituents in epithelial lining fluid of patients with acute respiratory distress syndrome.

OBJECTIVE: A noninvasive bronchoscopic microsampling (BMS) probe was developed to sample biochemical constituents of the epithelial lining fluid in small airways. DESIGN: Observational, controlled study. SETTING: Intensive care unit of academic medical center. PATIENTS AND PROCEDURE: BMS was applied in a control group of seven patients who had hemoptysis or small solitary peripheral nodules but no hypoxemia or other signs of acute inflammation and in four patients with acute respiratory distress syndrome (ARDS), to test whether BMS can ascertain the presence of acute pulmonary inflammation without complications. MEASUREMENTS AND RESULTS: Complications, including a significant decrease in arterial oxygen saturation, were observed neither during nor after BMS. In the ARDS group, albumin, lactate dehydrogenase, interleukin-6, basic fibroblast growth factor, and neutrophil elastase concentrations in epithelial lining fluid were significantly higher (p <.0001, p =.012, p <.0001, p <.0001, and p <.0001, respectively) than in the control group. Serial BMS was safely performed in one patient with ARDS, allowing us to observe a correlation between changes in the concentration of inflammation-related biochemical markers and clinical course of the disease. CONCLUSIONS: These results suggest that BMS is safe and useful to monitor pulmonary biochemical events in ARDS.

Agonist and antagonist activities on human NPFF(2) receptors of the NPY ligands GR231118 and BIBP3226.

Neuropeptide FF (NPFF) is a part of a neurotransmitter system acting as a modulator of endogenous opioid functions. At this time, no non-peptide or peptide NPFF-antagonists have been discovered. Here, we demonstrate that Neuropeptide Y (NPY) ligands, in fact possess significant ability to interact with the human NPFF(2) receptors. NPY Y(1) antagonist BIBP3226 and mixed Y(1) antagonist/Y(4) agonist GR231118 are able to displace with low affinity, 50 -- 100 nM, the specific binding on NPFF receptors expressed in CHO cells as well as in rat dorsal spinal cord, an affinity however superior to those determined against Y(2), Y(4) or Y(5) receptors. Furthermore, BIBP3226 which is unable to inhibit the forskolin-stimulated cyclic AMP production mediated by NPFF(2) receptors, antagonizes the effect of NPFF, revealing the first antagonist of NPFF receptors. These properties of NPY ligands on Neuropeptide FF receptors must be considered when evaluating pharmacological activities of these drugs.

Functional characterization of a human receptor for neuropeptide FF and related peptides.

1. Neuropeptides FF (NPFF) and AF (NPAF) are involved in pain modulation and opioid tolerance. These peptides were known to act through uncharacterized G protein-coupled receptors (GPCR). We describe here, using an aequorin-based assay as screening tool, that an orphan GPCR, previously designated HLWAR77, is a functional high affinity receptor for NPFF and related peptides. This receptor is further designated as NPFFR. 2. Binding experiments were performed with a new radioiodinated probe, [(125)I]-EYF, derived from the EFW-NPSF sequence of the rat NPFF precursor. Chinese hamster ovary (CHO) cell membranes expressing NPFFR bound [(125)I]-EYF with a K(d) of 0.06 nM. Various NPFF analogues and related peptides inhibited [(125)I]-EYF specific binding with the following rank order (K(i)): human NPAF (0.22 nM), SQA-NPFF (0.29 nM), NPFF (0.30 nM), 1DMe (0.31 nM), EYW-NPSF (0.32 nM), QFW-NPSF (0.35 nM), 3D (1.12 nM), Met-enk-RF-NH(2) (3.25 nM), FMRF-NH(2) (10.5 nM) and NPSF (12.1 nM). 3. The stimulatory activity of the same set of peptides was measured by a functional assay based on the co-expression of NPFFR, G(alpha 16) and apoaequorin. The rank order of potency was consistent with the results of the binding assay. 4. Membranes from NPFFR expressing CHO cells bound GTP gamma[(35)S] in the presence of SQA-NPFF. This functional response was prevented by pertussis toxin treatment, demonstrating the involvement of G(i) family members. 5. SQA-NPFF inhibited forskolin induced cyclic AMP accumulation in recombinant CHO cells in a dose dependent manner. This response was abolished as well by pertussis toxin pre-treatment. 6. RT -- PCR analysis of human tissues mRNA revealed that expression of NPFFR was mainly detected in placenta, thymus and at lower levels in pituitary gland, spleen and testis.

Expression of prostaglandin E receptor EP4 subtype in rat adrenal zona glomerulosa: involvement in aldosterone release.

We examined the role of prostaglandin (PG) E receptors in the secretion of aldosterone. PGE2 is known to exert its various biological functions by binding to PGE receptors. There are four subtypes of PGE receptors, EP1, EP2, EP3, and EP4. Among the PGE receptors EP2 and EP4 subtypes are coupled to Gs protein and stimulate adenylyl cyclase. In this study, PGE2 caused a dose-dependent increase in aldosterone production from the rat adrenal zona glomerulosa cells in vitro accompanied with an increase in intracellular cAMP concentration. A specific agonist for EP2, butaprost, did not increase the cAMP production or the aldosterone release, suggesting the possibility that EP4 mediates the secretion of aldosterone by PGE2. Northern blot hybridization analysis disclosed that EP4 gene was expressed in the rat adrenal gland but that EP2 gene was not. In situ hybridization revealed that EP4 mRNA is present abundantly in the zona glomerulosa of rat adrenal gland. These findings suggest that the PGE2-EP4 system is involved in the regulation of aldosterone secretion from the rat adrenal gland.

Multiple signal transduction pathways through two prostaglandin E receptor EP3 subtype isoforms expressed in human uterus.

PGE2 is known to induce uterine contraction by increasing intracellular Ca2+. In the present study, to investigate other functions of PGE2 in human uterus, two EP3 isoforms were isolated by the RT-PCR method using human uterus polyadenylated ribonucleic acid (RNA). These EP3 isoforms, named EP3-V and EP3-VI, are composed of 402 and 393 amino acid residues, respectively, which are unique compared with EP3 isoforms of other species. Their N-terminal 359 amino acid residues are identical to those of previously reported human EP3 isoforms, whereas the two isoforms contained a novel amino acid sequence in their C-terminal tails. The dissociation constant values of EP3-V and EP3-VI for PGE2 were 3.9 and 1.4 nmol/L, respectively, which were consistent with those of previously reported EP3 isoforms. Signaling experiments revealed that M&B28767, an EP3 agonist, not only inhibited forskolin-induced cAMP concentrations, but also activated mitogen-activated protein kinase in Chinese hamster ovary cells stably expressing EP3-V and EP3-VI. These responses were abolished by treatment with pertussis toxin. In addition, M&B28767 increased cAMP concentrations in EP3-VI-expressing cells, whereas it did not in EP3-V-expressing cells. M&B28767 did not stimulate phosphoinositide turnover in EP3-V or EP3-VI-expressing cells. EP3-V and EP3-VI messenger RNAs (mRNAs) were detected abundantly in human uterus, whereas weak, but substantial, bands were detected in the lung and kidney in RT-PCR specific for each mRNA. In situ hybridization revealed EP3-V and EP3-VI mRNAs in the human myometrium, but not in the endometrium. The present study suggests that EP3-V and EP3-VI are possibly involved in the proliferation of cells in human myometrium.

Egg envelope glycoprotein gp37 as a Xenopus homolog of mammalian ZP1, based on cDNA cloning.

The egg envelope is a kind of extracellular matrix, which surrounds growing oocytes, ovulated eggs and early embryos. Among the glycoprotein components of the Xenopus laevis egg envelope, gp43/gp41 and gp69/64 have already been shown to be frog homologs of the mammalian zona pellucida components ZP3 and ZP2, respectively. To determine the structure of another major component of egg envelope, gp37, the peptides isolated from the lysyl endopeptidase digests of gp37 were sequenced for amino acids to design degenerate primers for polymerase chain reaction. By reverse transcription-polymerase chain reaction with a poly(A)+ RNA from the ovary of a postovulated female Xenopus, a specifically amplified band was obtained and sequenced. The upstream and downstream sequences of the sequenced region were completed by 5'- and 3'-rapid amplification of cDNA ends, respectively. The gp37 cDNA comprises 1674 bp and contains one open reading frame encoding a polypeptide with 543 amino acids. The predicted amino acid sequence of the gp37 cDNA has a close similarity to that of mammalian ZP1. Northern blot and in situ hybridization studies indicated that the transcript (1.8 kb) is exclusively expressed in the oocytes, particularly in the previtellogenic young oocytes, just like the expression pattern of gp43 mRNA, suggesting a coordinate transcription of the gp43 and gp37 genes in Xenopus.

Ganglioside GT1b in rat brain binds to p58, a brain-specific sodium-dependent inorganic phosphate cotransporter: expression cloning with a specific monoclonal antibody to ganglioside GT1b-binding protein.

To evidence the notion that gangliosides involve neuronal cell interactions in the brain, we surveyed the presence of ganglioside-binding proteins in membrane lysates of adult rat cerebellum. Three proteins (p58, p90, and p160) were identified as GT1b-binding proteins by incubation of the blot of the membrane lysate with GT1b micelles. We generated a monoclonal antibody (mAb) specific to the polypeptide portion of the GT1b-binding proteins (YAK-2). The YAK-2 mAb specifically reacted with all three proteins on blots of proteins pretreated under nonreducing conditions for SDS-PAGE, but reacted mainly with p58 under reducing conditions, showing that p90 and p160 are oligomeric forms of p58. The binding activity of the YAK-2 mAb was completely inhibited by the presence of GT1b micelles, indicating the specificity of YAK-2 mAb for p58 and its oligomers. Immunohistochemical investigations revealed that both p58 and GT1b colocalize within the granular layer of adult rat cerebellum. Expression cloning of p58 cDNA was performed using YAK-2 mAb, and five putative clones were obtained. Among them, the nucleotide sequence of one cDNA completely matched that of rat brain-specific sodium-dependent inorganic phosphate cotransporter (rBNPI), a 61 kDa membrane protein. COS7 cells were transfected with a Flag-chimeric construct containing the rBNPI/p58 cDNA, and the membrane lysate was subjected to immunoprecipitation with anti-Flag antibody. One protein (64 kDa) was detected only with YAK-2 mAb, and the membrane lysate specifically bound to GT1b micelles. Taking together, we propose that rBNPI/p58 functions as a GT1b-binding protein in neuronal cells.

Bone marrow-derived cells are responsible for the development of autoimmune arthritis in human T cell leukemia virus type I-transgenic mice and those of normal mice can suppress the disease.

Previously, we reported that human T cell leukemia virus type I env-pX region-introduced transgenic (pX-Tg) mice developed an inflammatory polyarthropathy associated with a development of autoimmunity. To elucidate roles of autoimmunity in the development of arthritis, the immune cells were reciprocally replaced between pX-Tg mice and non-transgenic (Tg) mice. When bone marrow (BM) cells and spleen cells from pX-Tg mice were transferred into irradiated non-Tg mice, arthritis developed in these mice. In contrast, arthritis in pX-Tg mice was completely suppressed by non-Tg BM and spleen cells. Similar results were obtained with BM cells only. After the transplantation, T cells, B cells, and macrophages were replaced completely, whereas cells in the joints were replaced partially. In those mice, serum Ig and rheumatoid factor levels correlated with the disease development, and inflammatory cytokine expression was elevated in the arthritic joints. Furthermore, involvement of T cells in the joint lesion was suggested, because the incidence was greatly reduced in athymic nu/nu mice although small proportion of the mice still developed arthritis. These observations suggest that BM stem cells are abnormal, causing autoimmunity in pX-Tg mice, and this autoimmunity plays an important, but not absolute, role in the development of arthritis in this Tg mouse.

Identification of a novel R642C mutation in Na/Cl cotransporter with Gitelman's syndrome.

Gitelman's syndrome, a variant of Bartter's syndrome, is an inherited disorder characterized by hypokalemic metabolic alkalosis, hypomagnesemia, and hypocalciuria, and these abnormalities have recently been linked to the thiazide-sensitive Na/Cl cotransporter (TSC) gene. We evaluated three unrelated patients affected with this syndrome whose diagnosis was made based on clinical and biochemical features. The data of clearance studies in these patients were compatible with Gitelman's syndrome. We then investigated possible mutations of the TSC gene. In one patient whose parents are consanguineous, we identified a novel missense mutation in the TSC gene, which causes alteration of arginine to cysteine at codon 642 (R642C mutation) located in the cytoplasmic tail of the product. This mutation results in the loss of an MspI site in exon 15 of the TSC gene. MspI digestion analysis of genomic DNA fragments from the family was consistent with the autosomal recessive inheritance of the disorder, and presence of this mutation correlated with the clinical manifestations. Such mutation was not detected in 47 normal healthy subjects. In the second patient, we found another missense mutation in one allele of the TSC gene, which results in alteration of arginine to glutamine at codon 955. In the third patient, no mutation causing amino acid substitution was found in the TSC gene. These results indicate that the R642C mutation in TSC is critically important for impairment of this cotransporter function and also suggest the necessity of further investigations in the genetic background of Gitelman's syndrome.

Molecular basis for oviductin-mediated processing from gp43 to gp41, the predominant glycoproteins of Xenopus egg envelopes.

Acquisition of fertilizability in Xenopus coelomic eggs is correlated with the conversion from coelomic to vitelline envelope during passage of the eggs through the pars recta portion of oviduct. The conversion includes processing of a major envelope constituent gp43 of coelomic envelopes to gp41 of vitelline envelopes by a trypsin-type protease, oviductin, which is secreted from the pars recta. Our recent sequencing analyses [Kubo et al., (1997): Dev Growth Diff 39:405-411] strongly suggested that the N-terminal portion of gp41 is exposed as a result of oviductin digestion. In this study, a monoclonal antibody specific to the predicted N-terminus of gp41 was raised by immunizing mice with a synthetic N-terminal hexapeptide (QLPVSP) coupled to keyhole limpet hemocyanin. The antibody specifically reacted to gp41, but not to gp43, indicating that Gln62 is exposed as the N-terminal amino acid of gp41 by oviductin-mediated cleavage of gp43 at Arg61 in GSR61. The C-terminal sequencing of gp43 and gp41 indicated that Arg373 in GSR373 as the C-terminus of gp41 is generated by cleavage of three amino acid (WNQ) residues from the C-terminus of gp43. The resulting polypeptide moiety of gp41 has a molecular mass of 33900 Da with 312 amino acid residues. We propose that oviductin possessing the substrate specificity of GSR simultaneously digests gp43 at Arg residues in GSR61 and GSR373 to generate the N- and C-terminus of gp41, respectively.

Roles of prostaglandin E receptors in mesangial cells under high-glucose conditions.

BACKGROUND: High glucose reportedly stimulates prostaglandin (PG) E2 production and DNA synthesis in mesangial cells (MCs). However, the pathophysiological significance of PGE2 in MCs has remained unclear. METHODS: The effects of prostanoids on [3H]-thymidine uptake and cAMP production in rat MCs cultured with 5.6 mM glucose, 25 mM glucose, or 5.6 mM glucose supplemented with 19.4 mM mannitol were examined. The gene expression of PGE2 receptor (EP) subtypes in MCs was analyzed with Northern blotting techniques. RESULTS: Northern blotting indicated EP1 and EP4 gene expression in MCs. EP1 agonists and PGE2 stimulated [3H]-thymidine uptake in MCs. EP1 antagonists dose dependently attenuated high-glucose-induced [3H]-thymidine uptake, which suggests EP1 involvement, by an increase in intracellular Ca2+, in DNA synthesis of MCs. On the other hand, forskolin, db-cAMP, and 11-deoxy-PGE1, an EP4/EP3/EP2 agonist, significantly decreased DNA synthesis in MCs. These inhibitory effects are thought to be mediated via EP4 as a result of an increase in cAMP synthesis. The effects via EP4 seem to be particularly important because PGE2-induced cAMP synthesis was significantly attenuated in the high-glucose group compared with the mannitol group, in which [3H]-thymidine uptake did not increase in spite of augmented PGE2 production. CONCLUSION: The increase in DNA synthesis in MCs under high-glucose conditions can be explained, at least in part, by the high-glucose-induced inhibition of cAMP production via EP4, which augments EP1 function in conjunction with the overproduction of PGE2.

Urinary excretion of the vitronectin receptor (integrin alpha V beta 3) in patients with Fabry disease.

A renal disorder is one of the important manifestations of Fabry disease, but the details of the pathogenesis have not been clarified yet. We examined the possibility that the vitronectin receptor (VNR, integrin alpha V beta 3), one of the integrins, is involved in the progression of the renal injury in Fabry disease. We measured the urinary excretion of beta 3 originating from VNR in Fabry patients by immunoblotting analysis and enzyme-linked immunosorbent assay (ELISA). Immunofluorescent microscopic analyses for VNR and globotriaosylceramide were performed on urinary sediments from Fabry patients. Furthermore, beta 3 and vitronectin in kidney tissues were analyzed immunohistochemically. Immunoblotting analysis and ELISA showed that the urinary excretion of beta 3 originating from VNR was significantly increased in the Fabry group compared with both the pathological and healthy control groups. Immunofluorescent microscopy revealed the expression of VNR and accumulation of globotriaosylceramide in urinary sediments from the Fabry patients. Increased expression of beta 3 was observed in glomerular epithelial cells, and in Bowman's capsular epithelial layer and tubular cells, and the amount of vitronectin was moderately increased in the kidney tissues from the Fabry patients. The urinary excretion of VNR was increased, and the expression of VNR was observed in Fabry kidney tissues. The expression of VNR may be involved in the progression of the renal injury in this disease.

Involvement of autoimmunity against type II collagen in the development of arthritis in mice transgenic for the human T cell leukemia virus type I tax gene.

We previously reported that transgenic mice carrying the human T cell leukemia virus type I (HTLV-I) env-pX region (pX-transgenic mice) develop rheumatoid-like inflammatory arthropathy, and suggested involvement of autoimmunity in the pathogenicity. In this report, to elucidate pathogenesis of the arthritis, we investigated arthritogenic antigens in the joints. The TCR beta-chain variable region (Vbeta) repertoires in the lymphatic organs were normal in transgenic mice, however, specific Vbeta-positive T cells were expanded oligoclonally in the affected joints, suggesting that specific antigens, but not superantigens, were involved in the expansion of these T cells. These expanded T cells had the same TCR as those of lymph node T cells reactive to type II collagen (IIC). Moreover, these mice were susceptible to IIC-induced arthritis and oligoclonal T cells of the same Vbeta specificity as that found in spontaneously developed arthritic joint accumulated in the arthritic joints after immunization with IIC. These observations show that endogenous IIC is one of the arthritogenic antigens in the joint, suggesting tolerance break to this antigen in pX-transgenic mice.

Change in obstructive pulmonary function as a result of cumulative exposure to welding fumes as determined by magnetopneumography in Japanese arc welders.

OBJECTIVES: To examine the effect of chronic exposure to welding fumes on pulmonary function by a direct estimate of fumes accumulated in the lungs. METHODS: The strength of the residual magnetic field of externally magnetised lungs (LMF) was used as an estimate of fumes accumulated in the lungs. The results of forced spirometry manoeuvres obtained in 143 of 153 male welders in the original sample were cross sectionally evaluated according to LMF. Seven conventional forced spirogram indices and two time domain spirogram indices were used as pulmonary function indices, and height squared proportional correction was performed when necessary. RESULTS: The distribution of LMF values was considerably skewed towards positive. There was a weak but significant positive relation between age and log transformed LMF. Obstructive pulmonary function indices correlated well with LMF. After adjustment for age and smoking, however, a significant association with LMF was only found with percentage rate of forced expiratory volume in one second (FEV1%) divided by forced vital capacity (FVC) and mu, and average component of assumed time constant distribution of lung peripheral units. Neither FVC nor vital capacity (VC), as indices of restrictive disorders, showed a significant association with LMF. Based on the results of multiple regression analyses, a 0.6% decrease in FEV1% and 0.039 unit increase in mu were expected for each doubling of LMF. CONCLUSION: Obstructive changes in pulmonary function were found to be related to level of cumulative exposure to welding fume in male Japanese arc welders after controlling for age and smoking, assuming that LMF adequately reflects accumulation of welding fumes in the lungs.

Tissue factor expression and fibrin deposition in the lungs of patients with idiopathic pulmonary fibrosis and systemic sclerosis.

Although abnormalities of alveolar fibrin turnover have been reported to play a role in the development of idiopathic pulmonary fibrosis (IPF), the pathophysiological relevance remains unclear. We therefore investigated the localization of tissue factor (TF) and fibrin deposition in patients with IPF using immunohistochemistry and compared the results with those from patients who had interstitial pneumonia associated with systemic sclerosis (IP-SSc) and idiopathic bronchiolitis obliterans with organizing pneumonia (BOOP). Expression of TF-mRNA was also assessed, using in situ hybridization with a digoxigenin-labeled cRNA probe. In patients with IPF, IP-SSc, and idiopathic BOOP, the TF antigen was positively stained in type II pneumocytes and in some alveolar macrophages. The fibrin antigen was stained in the type II pneumocytes and the adjacent area. Tissue factor-mRNA was expressed in the type II pneumocytes and in some alveolar macrophages. Neither TF antigens nor TF-mRNA were detected in the normal lung. These results indicate that type II pneumocytes are a major source of TF, suggesting that TF production in these cells is closely related to fibrin deposition in the lungs of people with these diseases.

Loss of the tumor suppressor p53 gene at the liver cirrhosis stage in Japanese patients with hepatocellular carcinoma.

The incidence of p53 gene aberrations is reported to be about 20-50% in hepatocellular carcinomas (HCCs). In most cases, HCC is clinically preceded by liver cirrhosis, but the genetic changes in cirrhosis are not known well. Therefore, we studied the loss of heterozygosity (LOH) of the p53 gene in cirrhotic and neoplastic foci in the livers of patients with HCC. To assess the relationship between the LOH status of the p53 gene in the liver cirrhosis stage and that in HCC, we analyzed the samples microdissected from paraffin-embedded tissues using the polymerase-chain-reaction-based assay. We studied 18 patients with HCC. Fourteen of the 18 cases showed constitutional heterozygosity for the microsatellite markers. In 8 (57%) of the 14 informative cases, LOH was detected in primary HCCs. Among these 8 doubly informative (informative and LOH positive in primary HCC) cases, 5 cases (63%) showed LOH in liver cirrhosis lesions. The pattern of p53 allelic loss in the cirrhotic foci was identical with that in the corresponding tumor. The remaining 6 cases without LOH of the p53 gene in HCC showed on p53 loss in any cirrhotic foci. LOH of the p53 gene may occur before the development of HCC.