Hydrogen peroxide triggers the expression of Fas/FasL in astrocytoma cell lines and augments apoptosis

Fas expression increases in perinecrotic areas of glioblastoma. In this study the up-regulation of Fas/FasL by oxidative stress was shown. H(2)O(2) exposure increased Fas expression in two astrocytoma cell lines and cells became sensitive to agonistic anti-Fas antibody. FasL was up-regulated in astrocytoma cells. Apoptosis of Molt-4 cells was augmented by astrocytoma cells pretreated with H(2)O(2). Our findings suggest up-regulation of Fas in astrocytoma cells may lead them to be sensitive to apoptosis when cells are in oxidative stress. Whereas, the up-regulation of FasL may render astrocytoma cells cytotoxic to neighboring brain tissues and infiltrating immune cells.

Sea water or its components alter experimental irritant dermatitis in man

BACKGROUND/AIMS

Ocean bathing has been considered "healthy" for skin, but its efficacy remains testimonial in nature. Our aim was to evaluate the effects of sea water and its main components on experimental irritant contact dermatitis induced by sodium lauryl sulphate (SLS) cumulative irritation.

METHODS

After open application of 2% SLS for 10 min on volar forearm sites, solutions of sea water, 500 mM NaCl, 10 mM KCl, 55 mM MgCl2, 10 mM CaCl2, or deionized water were separately applied using filter paper discs for 20 min. The procedures were repeated daily for 2 weeks. The effects of the treatment were assessed daily using measurements of transepidermal water loss (TEWL), as an indicator of epidermal barrier function, and capacitance, as a parameter of stratum corneum water content.

RESULTS

Sea water, NaCl, and KCl significantly inhibited the increase of TEWL as compared with deionized water (P < 0.003, P < 0.05, P < 0.05, respectively). Sea water and NaCl inhibited the decrease of capacitance as well (P < 0.03, P < 0.01).

CONCLUSION

The effect of sea water may be attributed to skin barrier preservation by NaCl and KCl, and an emollient effect by NaCl.

Genetic enhancement of inflammatory pain by forebrain NR2B overexpression

N-methyl-D-aspartate (NMDA) receptors contribute to many brain functions. We studied the effect of forebrain-targeted overexpression of the NMDA receptor subunit NR2B on the response of mice to tissue injury and inflammation. Transgenic mice exhibited prominent NR2B expression and enhanced NMDA receptor-mediated synaptic responses in two pain-related forebrain areas, the anterior cingulate cortex and insular cortex, but not in the spinal cord. Although transgenic and wild type mice were indistinguishable in tests of acute pain, transgenic mice exhibited enhanced responsiveness to peripheral injection of two inflammatory stimuli, formalin and complete Freund's adjuvant. Genetic modification of forebrain NMDA receptors can therefore influence pain perception, which suggests that forebrain-selective NMDA receptor antagonists, including NR2B-selective agents, may be useful analgesics for persistent pain.

Trafficking of phosphatidylinositol 3-phosphate from the trans-Golgi network to the lumen of the central vacuole in plant cells

Very limited information is available on the role of phosphatidylinositol 3-phosphate (PI[3]P) in vesicle trafficking in plant cells. To investigate the role of PI(3)P during the vesicle trafficking in plant cells, we exploited the PI(3)P-specific binding property of the endosome binding domain (EBD) (amino acids 1257 to 1411) of human early endosome antigen 1, which is involved in endosome fusion. When expressed transiently in Arabidopsis protoplasts, a green fluorescent protein (GFP):EBD fusion protein exhibited PI(3)P-dependent localization to various compartments--such as the trans-Golgi network, the prevacuolar compartment, the tonoplasts, and the vesicles in the vacuolar lumen--that varied with time. The internalized GFP:EBD eventually disappeared from the lumen. Deletion experiments revealed that the PI(3)P-dependent localization required the Rab5 binding motif in addition to the zinc finger motif. Overexpression of GFP:EBD inhibited vacuolar trafficking of sporamin but not trafficking of H(+)-ATPase to the plasma membrane. On the basis of these results, we propose that the trafficking of GFP:EBD reflects that of PI(3)P and that PI(3)P synthesized at the trans-Golgi network is transported to the vacuole through the prevacuolar compartment for degradation in plant cells.

Formation of cleavage products by autoxidation of lycopene

The cleavage products formed by autoxidation of lycopene were evaluated in order to elucidate possible oxidation products of lycopene in biological tissues. Lycopene solubilized at 50 microM in toluene, aqueous Tween 40, or liposomal suspension was oxidized by incubating at 37 degrees C for 72 h. Among a number of oxidation products formed, eight products in the carbonyl compound fraction were identified as 3,7,11 -trimethyl-2,4,6,10-dodecatetraen-1-al, 6,10,14-trimethyl-3,5,7,9,13-pentadecapentaen-2-one, acycloretinal, apo-14'-lycopenal, apo-12'-lycopenal, apo-10'-lycopenal, apo-8'-lycopenal, and apo-6'-lycopenal. These correspond to a series of products formed by cleavage in the respective 11 conjugated double bonds of lycopene. The maximal formation of acycloretinal was 135 nM in toluene, 49 nM in aqueous Tween 40, and 64 nM in liposomal suspension. Acycloretinoic acid was also formed by autoxidation of lycopene, although its formation was lower in the aqueous media than in toluene. The pig liver homogenate had the ability to convert acycloretinal to acycloretinoic acid, comparable to the conversion of all-transretinal to all-trans-retinoic acid. These results suggest that lycopene might be cleaved to a series of apolycopenals and short-chain carbonyl compounds under the oxidative conditions in biological tissues and that acycloretinal is further enzymatically converted to acycloretinoic acid.

Insulin-like growth factor-1 protects H9c2 cardiac myoblasts from oxidative stress-induced apoptosis via phosphatidylinositol 3-kinase and extracellular signal-regulated kinase pathways

Oxidative stress plays a critical role in cardiac injuries during ischemia/reperfusion. Insulin-like growth factor-1 (IGF-1) promotes cell survival in a number of cell types, but the effect of IGF-1 on the oxidative stress has not been elucidated in cardiac muscle cells. Therefore, we examined the role of IGF-1 signaling pathway in cell survival against H2O2-induced apoptosis in H9c2 cardiac myoblasts. H2O2 treatment induced apoptosis in H9c2 cells, and pretreatment of cells with IGF-1 suppressed apoptotic cell death. The antiapoptotic effect of IGF-1 was blocked by LY294002 (an inhibitor of phosphatidylinositol 3-kinase) and by PD98059 (an inhibitor of extracellular signal-regulated kinase (ERK)). The protective effect of IGF-1 was also blocked by rapamycin (an inhibitor of p70 S6 kinase). Furthermore, H9c2 cells stably transfected with constitutively active PI 3-kinase (H9c2-p110*) and Akt (H9c2-Gag-Akt) constructs were more resistant to H2O2 cytotoxicity than control cells. Although H2O2 activates both p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), IGF-1 inhibited only JNK activation. Activated PI 3-kinase (H9c2-p110*) and pretreatment of cells with IGF-1 down-regulated Bax protein levels compared to control cells. Taken together, our results suggest that IGF-1 transmits a survival signal against oxidative stress-induced apoptosis in H9c2 cells via PI 3-kinase and ERK-dependent pathways and the protective effect of IGF-1 is associated with the inhibition of JNK activation and Bax expression.

Skewed abrogation of tolerance to a neo self-antigen in double-transgenic mice coexpressing the antigen with interleukin-1beta or interferon-gamma

Transgenic (Tg) mice expressing hen egg lysozyme (HEL) under the control of the alphaA-crystallin promoter exhibit tolerance to HEL by both their T- and B-cell compartments. Here, we show that double-Tg mice, coexpressing HEL with either interleukin-1beta or interferon (IFN)-gamma, demonstrated unresponsiveness to HEL by their T-cell compartment, but most of them developed antibodies against HEL following a challenge with the antigen. The abrogation of humoral tolerance was more pronounced in the HEL/IL-1 double-Tg mice than in the HEL/IFN-gamma mice. Unlike their controls, double-Tg mice exhibited remarkable levels of variability in their antibody levels. The skewed abrogation of tolerance in the double-Tg mice is proposed to be due to the cytokines' capacity to rescue from clonal deletion small numbers of T cells, which provide help to antibody producing B cells. This notion is supported by the finding that adoptive transfer of small numbers of Th1 or Th2 cells into HEL-Tg mice made possible antibody production similar to that seen in the double-Tg mice.

Mechanism of induction of transforming growth factor-beta type II receptor gene expression by v-Src in murine myeloid cells

Transforming growth factor (TGF)-beta1 plays an important role during hematopoiesis. Previously, we had shown that the growth of a v-Src-transformed myeloid cell line was markedly more inhibited by TGF-beta treatment when compared with the wild-type myeloid cell line. To investigate the increased growth sensitivity of the v-Src-transformed myeloid cell line, 32D-src, to TGF-beta, we examined expression of the TGF-beta type II receptor (TGF-beta RII) gene in myeloid cell lines. Northem blot analysis showed that expression of approximately 8- and 6-kb species of TGF-beta RII transcripts was markedly increased in the 32D-src cell line. The expression of the TGF-beta RII promoter linked to a reporter gene was increased 23-fold by v-Src. DNA transfection and electrophoretic mobility shift assay revealed that v-Src induces TGF-beta RII promoter activity through an AP1/ATF2-like sequence (-219 to -172), ETS binding sites (+1 to +36), and the inverted CCAAT box (-81 to -77). Novel DNA-protein complexes with ETS binding sites are significantly increased in v-src-transformed cell lines compared with the control cell line. These results suggest that v-Src induces activity of the TGF-beta RII promoter through multiple elements by inducing expression of nuclear proteins interacting with these elements.

Mutation in hepatocyte nuclear factor-1alpha is not a common cause of MODY and early-onset type 2 diabetes in Korea

Maturity-onset diabetes of the young (MODY)-3 with a mutation in hepatocyte nuclear factor (HNF)-1alpha has been identified in most races, but the prevalence of Korean MODY and early-onset type 2 diabetes with a mutation in this gene is unknown. To determine the prevalence of MODY and early-onset type 2 diabetes with the mutation of HNF-1alpha gene in Korea, we analyzed this gene in 69 Korean early-onset type 2 diabetics and in 35 healthy persons using the single-strand conformation polymorphism (SSCP) technique and direct sequencing. We identified one mutation in exon 4 (C900A) in only one of the 69 Korean subjects with early-onset type 2 diabetes; this mutation was silent and did not change the amino acid (Pro300). Additionally, we identified four polymorphisms: S487N, AAC-->AGC, intron 2 (nt -23), intron 7: (nt +7) and intron 9 (nt -24). However, there was no significant difference in frequencies of the four polymorphisms between the type 2 diabetes and control groups. Among type 2 diabetics, codon 487 variant showed no relationship to age at onset, body mass index, fasting blood glucose, HbA1c, lipid profile, basal C-peptide and 2 hour C-peptide. We concluded that this genetic mutation in HNF-1alpha gene may not be a common contributor to MODY and early-onset type 2 diabetes susceptibility in Korea.

Expression of interleukin-8 correlates with angiogenesis, tumorigenicity, and metastasis of human prostate cancer cells implanted orthotopically in nude mice

We determined whether the expression of interleukin-8 (IL-8) by human prostate cancer cells correlates with induction of angiogenesis, tumorigenicity, and production of metastasis. Low and high IL-8-producing clones were isolated from the heterogeneous PC-3 human prostate cancer cell line. The secretion of IL-8 protein correlated with transcriptional activity and levels of IL-8 mRNA. All PC-3 cells expressed both IL-8 receptors, CXCR1 and CXCR2. The low and high IL-8-producing clones were injected into the prostate of nude mice. Titration studies indicated that PC-3 cells expressing high levels of IL-8 were highly tumorigenic, producing rapidly growing, highly vascularized prostate tumors with and a 100% incidence of lymph node metastasis. Low IL-8-expressing PC-3 cells were less tumorigenic, producing slower growing and less vascularized primary tumors and a significantly lower incidence of metastasis. In situ hybridization (ISH) analysis of the tumors for expression of genes that regulate angiogenesis and metastasis showed that the expression level of IL-8, matrix metalloproteinases, vascular endothelial growth factor (VEGF), and E-cadherin corresponded with microvascular density and biological behavior of the prostate cancers in nude mice. Collectively, the data show that the expression level of IL-8 in human prostate cancer cells is associated with angiogenesis, tumorigenicity, and metastasis.

Identification and characterization of multiple isoforms of a mouse ribosome receptor

We isolated multiple cDNA clones encoding various isoforms of a mouse ribosome receptor protein (mRRp). The cDNAs were isolated from a 13.5-day-old mouse conceptus cDNA library by polymerase chain reaction-based screening. The predicted proteins encoded by these cDNAs showed significant homology with ribosome receptors present in dogs (83%), humans (80%), and chickens (45%). The cDNA isoforms had highly identical N- and C-terminal sequences but differed in their central sequences, suggesting that these cDNA isoforms may be derived by alternative splicing from a single gene. Genomic Southern blot analysis confirmed the existence of only a single mouse ribosome receptor gene. Alignments of the deduced amino acid sequences of the mRRp cDNA isoforms revealed that they differ in the number of decapeptide repeats present in the central domain of the protein. These repeats have been previously suggested to mediate ribosome binding and thus differences in repeat number may translate to different ribosome binding abilities. The longest mRRp isoform had 61 tandem repeats. This is of interest because in the human and canine ribosome receptor proteins there are only 54 tandem repeats, suggesting that humans and dogs may also have larger ribosome receptor protein isoforms. Surprisingly, mRRp has a very short basic C-terminal sequence of only 35 amino acids, while in contrast, the known human and canine forms of this protein have acidic C-terminal regions comprised of 803 and 798 amino acid residues, respectively. Although the function of the C-terminal region is currently unknown, it may be that those C-terminal sequences that are present in human and canine RRp proteins but missing in mRRp do not play critical roles in RRp function. The cDNA of the ES/130 isoform, which lacks tandem repeats and presumably are unable to bind ribosomes, could be isolated by reverse transcriptase-PCR from E 13.5 mouse embryos. mRRp mRNAs were expressed in all tissues examined but expression levels of each isoform differed between tissues. The identification of multiple mRRp isoforms in the mouse will allow us to study the regulation and function of ribosome receptors on a genetic level.

Proteome analysis of light-induced proteins in Synechocystis sp. PCC 6803: identification of proteins separated by 2D-PAGE using N-terminal sequencing and MALDI-TOF MS

The cyanobacterium Synechocystis sp. PCC 6803 is an ideal model organism for the proteome study of light-induced gene expression because the whole genomic sequence has been determined. The soluble proteins extracted from light- and dark-cultured cells were separated by two-dimensional polyacrylamide gel electrophoresis. Light-induced protein spots electroblotted on a polyvinyldiene difluoride membrane were analyzed by N-terminal Edman sequence determination and followed by CyanoBase. The tryptic digests of some proteins were also confirmed by matrix-assisted laser desorption ionization/time-of-flight (MALDI-TOF) and MS-Fit search. Interestingly, eight proteins were related to photosynthesis and respiration (RbcS/L, CbbA, Gap2, AtpB, CpcB, PsbO, and PsbU). Four proteins (SodB, DnaK, GroEL2, and Tig) were involved in cellular processes and the functions of another two proteins (rehydrin and membrane protein) were unknown. The proteome analysis by N-terminal Edman sequencing and MALDI-TOF enabled us to characterize one-shot protein profiles expressed under different physiological conditions.

Clinical results of the transjugular intrahepatic portosystemic shunt (TIPS) for the treatment of variceal bleeding

BACKGROUND

Transjugular intrahepatic portosystemic shunt (TIPS) has been popularized for the treatment of refractory variceal bleeding. The aim of this study was to assess the safety and long-term effect of TIPS in the treatment of variceal bleeding that is not controlled with pharmacological and endoscopic treatment.

METHODS

Thirty-six patients who underwent transjugular intrahepatic portosystemic shunt (TIPS) due to refractory variceal bleeding were included in the study. The effectiveness of portal decompression and bleeding control was evaluated. Upper gastrointestinal endoscopy was performed to analyse the degree of varices and portal hypertensive gastropathy (PHG) before TIPS procedure and one to three weeks after TIPS. Angiography was performed in surviving patients, if bleeding recurred, or if ultrasonography or endoscopy suggested stent dysfunction.

RESULTS

TIPS were successfully placed in 36 of 38 patients (94.6%). TIPS achieved hemostasis of variceal bleeding in 34 patients (94.4%). Portal venous pressure decreased from an initial average of 28.7 +/- 7.9 to 23.2 +/- 9.4 mmHg after TIPS (p < 0.05). The portosystemic pressure gradient was significantly decreased from 15.5 +/- 6.3 to 7.8 +/- 4.1 mmHg (p < 0.01). The degree of esophagogastric varices and PHG was significantly improved after TIPS. The total length of follow-up was from one day to 54 months (mean: 355 days). The actuarial probability of survival was 83% at one year and 74% at two years. Overall, 16 episodes of stent dysfunction were diagnosed during follow-up. Stent revision by means of angioplasty was successfully performed in 14 of these episodes.

CONCLUSION

TIPS is an effective and reliable nonoperative means of lowering portal pressure. This procedure has proved useful in the management of acute variceal bleeding refractory to endoscopic treatment. Surveillance by ultrasonography, endoscopy, and angiographic intervention is useful for the maintenance of shunt patency.

Bleeding Dieulafoy's lesions and the choice of endoscopic method: comparing the hemostatic efficacy of mechanical and injection methods

BACKGROUND

Dieulafoy's lesion has unique endoscopic and histopathologic characteristics. This is a clinical trial of endoscopic therapy in 24 patients with Dieulafoy's lesions.

METHODS

Patients were divided into 2 groups according to initial endoscopic treatment method. Data were analyzed with respect to clinical and endoscopic characteristics as well as outcomes. The 24 patients were evenly divided into mechanical (9 hemoclipping, 3 band ligation) and injection groups (12).

RESULTS

The average number of therapeutic endoscopic sessions needed to achieve permanent hemostasis for the mechanical and injection groups were 1.17 and 1.67, respectively. Initial hemostasis was achieved in 91.7% of patients undergoing mechanical therapy and 75% of those undergoing injection therapy, with none in the former group needing subsequent surgery in comparison to 17% of the latter group. The rate of recurrent bleeding in the mechanical therapy group was significantly lower in comparison to the injection therapy group (8.3% versus 33.3%, p < 0. 05).

CONCLUSIONS

Higher efficacy in terms of initial hemostasis and less recurrent bleeding was achieved by mechanical hemostatic therapy with hemoclip and band ligation compared with injection therapy. Endoscopic mechanical therapy is recommended as effective for bleeding Dieulafoy's lesions.

Combined periodontal-prosthodontic treatment of early-onset periodontitis--an alternative to implant therapy

A variety of treatment systems should be available for patients whose dentitions are seriously compromised so that they may select customized treatment modalities that satisfactorily restore occlusal function, consider systemic conditions, and lessen the surgical and financial burdens. These requirements become more demanding when clinicians are faced with advanced cases of rapidly progressive periodontitis. Therefore, it is critical to establish sophisticated multidisciplinary treatment modalities for the successful management of these compromised patients. Obviously, because of various limitations, implant therapy cannot be the only solution. This article reports on the successful long-term management of seriously compromised early-onset periodontitis by a combined periodontal-prosthetic treatment as an alternative to implant therapy.

Development of pulmonary arteriovenous fistulas after bidirectional cavopulmonary shunt

BACKGROUND

A high incidence of pulmonary arteriovenous fistulas (PAVF) has been reported after bidirectional cavopulmonary shunt (BCPS) or total cavopulmonary shunt (TCPS; BCPS in patients with interrupted inferior vena cava). However, the definite diagnostic criteria or standard diagnostic modality of PAVF has not yet been defined. The goal of this study was to evaluate the diagnostic modalities and the prevalence of PAVF.

METHODS

We selected 10 patients with TCPS and 27 patients with BCPS. Lung perfusion scan, contrast echocardiogram, and pulmonary angiogram were performed. The results were compared among groups of patients and among each diagnostic modality.

RESULTS

All 10 patients with TCPS and 16 and 13 patients with BCPS showed positive results on contrast echocardiograms and lung scans, respectively. Six patients with TCPS and 4 patients with BCPS showed positive results on pulmonary angiograms. All patients with TCPS developed subclinical or clinical PAVF and 19 patients with BCPS developed subclinical PAVF and none of them had clinical PAVF during the short-term follow-up.

CONCLUSIONS

Most patients with bidirectional cavopulmonary anastomosis have subclinical evidence of right-to-left intrapulmonary shunting. This problem can be demonstrated with various diagnostic modalities.

Inhibitory effects of cimicifugae rhizoma extracts on histamine, bradykinin and COX-2 mediated inflammatory actions

Rhizoma Cimicifugae (RC) has been used traditionally to treat pain and inflammation in Korea. The present study was conducted to gain insights into the mechanism of action regarding analgesic and antiinflammatory activities of RC extracts. RC was first extracted with methanol. The methanol extract (A) was fractionated to an ether-soluble fraction (B) and a water-soluble fraction (C). Fraction C was fractionated to a butanol-soluble fraction (D) and a water-soluble fraction (E). Each fraction (100 mg/kg, i.p.) was tested for analgesic and antiinflammatory activities. Administration of fractions A and D caused dramatic analgesic effects based on acetic acid writhing and tail-flick assays. However, fraction E had an analgesic effect only based on the acetic acid writhing assay. Fractions A, D and E exerted antiinflammatory effects on the rat paw oedema assay. The fractions A, D, E had an inhibitory action on the bradykinin/histamine-mediated contractions of guinea-pig ileum. In addition, fractions A, D and E had the ability to inhibit the production of LPS-induced 6-keto-PGF1alpha production in macrophage cultures. Taken together, these results provide scientific evidence that RC extracts exert analgesic and antiinflammatory effects by inhibiting bradykinin/histamine mediated actions and inhibiting 6-keto-PGF1alpha induction.

Water extract of 1:1 mixture of Phellodendron cortex and Aralia cortex has inhibitory effects on oxidative stress in kidney of diabetic rats

Enhanced activity of the lipid peroxidation and oxidative damages have been implicated in the pathogenesis of diabetic kidney complications. We explored to determine whether these changes in diabetic kidney could be prevented by water extract of mixture of Phellodendron cortex and Aralia cortex (P55A). Greatly elevated content of thiobarbituric acid reactive substances (TBARS) and carbonylated protein in kidneys of diabetic rats were significantly reduced by P55A treatment. In addition, abnormally low ratio of GSH/GSSG in diabetic kidneys was elevated to almost normal levels by the treatment with P55A. These results suggest that P55A extracts exert antioxidant effect by reducing lipid peroxidation and protein carbonylation as well as by elevating the ratio of GSF/GSSG in diabetic kidney.

Clinics in diagnostic imaging (56). Cavernous vascular malformation with intracerebral haematoma

A 28-year-old woman presented following a seizure. Physical and neurological examinations showed no significant abnormality except a drowsy mental state. Routine laboratory studies were normal. Emergency MR imaging showed a rounded, high signal intensity lesion with a focal eccentric heterogeneous signal focus in the right frontal lobe. The heterogeneous focus revealed an irregular low signal rim on T1- and T2-weighted images. Mild surrounding parenchymal oedema was noted. The eccentric focus showed some central enhancement. The diagnosis of cavernous vascular malformation with intracerebral haematoma was confirmed at surgery. The combination of typical MR imaging findings, with clinical and family histories consistent with cavernous angiomata provides sufficient conclusive evidence.

A novel mitochondrial septin-like protein, ARTS, mediates apoptosis dependent on its P-loop motif

Here we describe a protein product of the human septin H5/PNUTL2/CDCrel2b gene, which we call ARTS (for apoptosis-related protein in the TGF-beta signalling pathway). ARTS is expressed in many cells and acts to enhance cell death induced by TGF-beta or, to a lesser extent, by other apoptotic agents. Unlike related septin gene products, ARTS is localized to mitochondria and translocates to the nucleus when apoptosis occurs. Mutation of the P-loop of ARTS abrogates its competence to activate caspase 3 and to induce apoptosis. Taken together, these observations expand the functional attributes of septins previously described as having roles in cytokinesis and cellular morphogenesis.

Hypersensitivity pneumonitis caused by Fusarium napiforme in a home environment

BACKGROUND

We report a case of hypersensitivity pneumonitis (HP) in a 17-year-old male student caused by Fusarium napiforme found in his home environment.

METHODS

The patient was diagnosed according to history, chest radiograph, spirometry, high-resolution chest CT, and transbronchial lung biopsy. To identify the causative agent, cultured aeromolds were collected by the open-plate method. From the main fungi cultured, fungal antigens were prepared, and immunoblot analysis with the patient's serum and each fungal antigen was performed.

RESULTS

Five fungal species were isolated from the patient's home. Immunoblotting analysis with the patient's serum demonstrated more than 10 IgG-binding fractions to F. napiforme extract only, while little binding was noted with the other fungal antigens.

CONCLUSIONS

We should be aware that HP may be caused by F. napiforme in the home environment.

The clinical significance of upper gastrointestinal endoscopy in gastrointestinal vasculitis related to scrub typhus

BACKGROUND AND STUDY AIMS

Scrub typhus is an acute febrile illness caused by Rickettsia tsutsugamushi-induced vasculitis, which is common in Asia and the Pacific islands and is sometimes encountered in Western countries because of increased travel and economic changes spurred by world globalization. Skin rash and eschar are typical physical findings on the trunk and extremities, but endoscopic mucosal changes have not been described in the gastrointestinal tract until now. We aimed to describe different endoscopic characteristics of the gastrointestinal manifestation of scrub typhus, to ascertain the necessity for endoscopy, and to determine correlations between the degrees of endoscopic lesion and clinical severity, including cutaneous manifestation.

PATIENTS AND METHODS

Between January 1993 and October 1998, out of 256 scrub typhus patients, we applied esophagogastroduodenoscopy to 58 patients who complained of gastrointestinal symptoms but had no past history of these symptoms. We categorized clinical severity into four grades according to the degree of six clinical indicators of systemic complications, and endoscopic findings were graded from I to IV (I, normal, nonspecific hyperemia; II, distinct hyperemia, petechiae, purpura; II, superficial hemorrhage, erosion; IV, ulcer, active bleeding).

RESULTS

Endoscopic findings of scrub typhus were characterized by petechiae, superficial hemorrhage, erosion, ulcers, and vascular bleeding (grade I, 14 patients; grade II, 11 patients; grade III, 16 patients; grade IV, 17 patients). In 83.3% of patients there was multiple occurrence of lesions without any predilection sites. Clinical severity was graded (grade I, 7 patients; grade II, 23 patients; grade III, 22 patients; grade IV, 6 patients). There was a correlation between clinical severity and endoscopic findings (P < 0.01). The grade of lesion was high in patients with cutaneous lesions (r(s) 0.359, P < 0.01). In two cases of gastric vascular bleeding, complete hemostasis was achieved by endoscopic hemoclipping.

CONCLUSIONS

The major endoscopic features that can develop in scrub typhus are superficial mucosal hemorrhage, multiple erosions and ulcers without any predilection sites, and unusual vascular bleeding. The endoscopic features are related to cutaneous lesions and severity of the disease. Endoscopy is useful for diagnosis and management of gastrointestinal vasculitis related to scrub typhus.

Background nonselective cationic current and the resting membrane potential in rabbit aorta endothelial cells

The ion channel conductances that regulate the membrane potential was investigated by using a perforated patch-clamp technique in rabbit aorta endothelial cells (RAECs). The whole-cell current/voltage (I-V) relation showed a slight outward rectification under physiological ionic conditions. The resting membrane potential was -23.3 +/- 1.1 mV (mean +/- SEM, n = 19). The slope conductances at the potentials of -80 and 50 mV were 31.0 +/- 4.0 and 62.8 +/- 7.1 pS pF(-1), respectively (n = 15). Changes in the extracellular and intracellular Cl(-) concentrations did not affect the reversal potential on I-V curves. The background nonselective cationic (NSC) current was isolated after the K(+) current was suppressed. The relative permeabilities calculated from the changes in reversal potentials using the constant-field theory were P(K):P(Cs):P(Na):P(Li) = 1:0.87:0.40:0.27 and P(Cs):P(Ca) = 1:0.21. Increases in the external Ca(2+) decreased the background NSC current in a dose-dependent manner. The concentration for half block by Ca(2+) was 1.1 +/- 0.3 mM (n = 7). Through the continuous recording of the membrane potential in a current-clamp mode, it was found that the background NSC conductance is the major determinant of resting membrane potential. Taken together, it could be concluded that the background NSC channels function as the major determinant for the resting membrane potential and can be responsible for the background Ca(2+) entry pathway in freshly isolated RAECs.