Carbon Nitride Loaded with an Ultrafine, Monodisperse, Metallic Platinum-Cluster Cocatalyst for the Photocatalytic Hydrogen-Evolution Reaction

For the realization of a next-generation energy society, further improvement in the activity of water-splitting photocatalysts is essential. Platinum (Pt) is predicted to be the most effective cocatalyst for hydrogen evolution from water. However, when the number of active sites is increased by decreasing the particle size, the Pt cocatalyst is easily oxidized and thereby loses its activity. In this study, a method to load ultrafine, monodisperse, metallic Pt nanoclusters (NCs) on graphitic carbon nitride is developed, which is a promising visible-light-driven photocatalyst. In this photocatalyst, a part of the surface of the Pt NCs is protected by sulfur atoms, preventing oxidation. Consequently, the hydrogen-evolution activity per loading weight of Pt cocatalyst is significantly improved, 53 times, compared with that of a Pt-cocatalyst loaded photocatalyst by the conventional method. The developed method is also effective to enhance the overall water-splitting activity of other advanced photocatalysts such as SrTiO3 and BaLa4 Ti4 O15 .

Periodontal pathogen accelerates lipid peroxidation and atherosclerosis

Recent studies have shown an association between periodontal disease and cardiovascular disease. We previously reported that intravenous challenge with Aggregatibacter actinomycetemcomitans (Aa) accelerated atherosclerosis in apolipoprotein E-deficient spontaneously hyperlipidemic (Apoe(shl)) mice. In this study, we investigated whether live cells were required for atherosclerosis induction or whether lipopolysaccharide (LPS) alone was sufficient to increase atherosclerotic damage. Mice were injected intravenously with live Aa HK1651, heat-killed (H.K.) Aa, or Aa LPS 3 times a week for 3 weeks and were sacrificed at 15 weeks of age. The areas of the aortic sinus that were covered with atherosclerotic plaques were significantly larger in mice treated with live Aa, H.K. Aa, or Aa LPS compared with vehicle-challenged mice. The order of the extent of atherosclerosis was live Aa > H.K. Aa > Aa LPS > sham. Toll and nucleotide oligomerization domain (NOD)-like receptor mRNA expression significantly increased in the live Aa, H.K. Aa, and Aa LPS treatment groups. Aa challenge markedly promoted the oxidation of LDL through oxidative stress involving NADPH oxidase- and myeloperoxidase-derived reactive oxygen species. These results suggested that Aa promoted innate immune signaling and low-density lipoprotein (LDL) oxidation and may facilitate atheroma development.

Clinical course of drug-induced hypersensitivity syndrome treated without systemic corticosteroids

BACKGROUND/AIM

Drug-induced hypersensitivity syndrome (DIHS) is a severe reaction to drugs which characteristically occurs after a long latency period. In addition, human herpes virus 6 (HHV-6) reactivation is a characteristic finding in DIHS, which has been known to be related to disease severity. Because DIHS has generally been treated by systemic corticosteroids, the natural clinical course is not clear.

METHODS

Data for patients with both DIHS and HHV-6 reactivation were retrospectively collected from four hospitals.

RESULTS

Data were collected on 12 patients ranging in age from 21 to 76 years (median, 65.5). All cases had been suspected of DIHS at their initial visit, and the elevation of serum anti-HHV-6 antibody had been confirmed (4-256 times: median; 32). The culprit drugs were carbamazepine (6), salazosulfapyridine (4), mexiletine (1) and zonisamide (1). The period of latency from the first administration of the drug ranged from 15 to 50 days (median, 30). All patients were treated conservatively for DIHS without systemic corticosteroids. The peaks of the patients' symptoms and laboratory findings were as follows (days from the onset of skin lesions): fever, 4-16 (median, 10.5); liver abnormality, 3-22 (median, 7.5); leukocytosis, 7-20 (median, 9). All patients recovered without pneumonia, myocarditis, nephritis or other systemic disease, from 7 to 37 days (median, 18) after withdrawal of the drug and from 11 to 44 days (median, 21) after the onset of skin lesions.

CONCLUSION

It might be unnecessary to give systemic corticosteroids immediately to all patients suspected of having DIHS.

Novel resistin promoter polymorphisms: association with serum resistin level in Japanese obese individuals

OBJECTIVES

Resistin, an adipocyte-secreted cytokine recently discovered in mice, has been proposed as a link between obesity and diabetes. We analyzed resistin gene polymorphisms and examined their association with serum resistin level and obesity phenotypes in humans.

SUBJECTS AND METHODS

Sixty young, obese, non-diabetic subjects taking no medication were studied. DNA sequencing and genotyping of identified single nucleotide polymorphisms were performed. Associations between polymorphisms and serum resistin level, BMI, body composition, fat distribution, and several indices of insulin sensitivity were examined. Moreover, single nucleotide polymorphisms in the promoter region were examined for their influence on resistin gene transcriptional activity using luciferase reporter vectors.

RESULTS

Ten non-coding single nucleotide polymorphisms were found. The -638G>A, -420C>G, and -358G>A polymorphisms in the promoter region showed marked linkage disequilibrium with each other, and were associated with serum resistin level; however, there was no association between these polymorphisms and parameters related to adiposity or insulin resistance. The results of luciferase assay revealed that -638G>A together with the -420C>G polymorphism influenced resistin gene transcriptional activity.

CONCLUSION

We found that variability in the serum resistin level might be related to polymorphic variants of the promoter region of the gene.

Suppressive effects of breast milk on oxidative DNA damage in very low birthweight infants

BACKGROUND

Human milk contains many kinds of antioxidant and is considered to prevent diseases mediated by oxygen free radicals in very low birthweight (VLBW) infants.

AIMS

To examine the antioxidant effects of breast milk in VLBW infants by determining urinary 8-hydroxydeoxyguanosine (8-OHdG) excretion, which is known to be a non-invasive marker for in vivo oxidative DNA damage.

METHODS

Urinary 8-OHdG concentrations were measured in 15 breast fed and 14 formula fed VLBW infants at 2, 7, 14, and 28 days of age.

RESULTS

Urinary 8-OHdG excretion at 14 and 28 days of age was significantly lower than at 2 and 7 days of age in the breast fed group, and significantly lower than in the formula fed group.

CONCLUSION

This is the first direct evidence of the antioxidant action of human milk in VLBW infants.

Development of cDNA microarray for expression profiling of estrogen-responsive genes

Estrogen plays an important role in many physiological events including carcinogenesis and the development of human breast cancer. However, the molecular mechanisms of estrogen signaling in cancers have not been clarified hitherto and accurate therapeutic prediction of breast cancer is earnestly desired. We first carried out estrogen-responsive expression profiling of approximately 9000 genes in estrogen receptor-positive human MCF-7 breast cancer cells. Based on the results, estrogen-responsive genes were selected for production of a custom-made cDNA microarray. Using a microarray consisting of the narrowed-down gene subset, we first analyzed the time course of the estrogen-responsive gene expression profiles in MCF-7 cells, resulting in subdivision of the genes up-regulated by estrogen into early-responsive and late-responsive genes. The expression patterns of several genes were confirmed by Northern blot analysis. We also analyzed the effects of the estrogen antagonists ICI 182780 and 4-hydroxytamoxifen (OHT) on the estrogen-responsive gene expression profiles in MCF-7 cells. While the regulation of most of the genes by estrogen was completely abolished by ICI 182780, some genes were partially regulated by estrogen even in the presence of OHT. Furthermore, the estrogen-responsive gene expression profiles of twelve cancer cell lines derived from the breast, ovary, stomach and other tissues were obtained and analyzed by hierarchical clustering including the profiles in MCF-7 cells. Several genes also showed up-regulation or down-regulation by estrogen in cell lines other than MCF-7 cells. The significance of the estrogen-responsive genes identified in these analyses concerning the nature of cancer is discussed.

OsPAA2, a distinct alpha 1 subunit gene for the 20S proteasome in rice (Oryza sativa L.)

The 20S proteasome is the proteolytic complex that is involved in removing abnormal proteins and other diverse biological functions. The 20S proteasome is constituted of 28 subunits arranged in four rings of seven subunits, and exists as a hollow cylinder. The two outer rings and the two inner rings are composed of seven different alpha and beta type subunits, respectively, giving an alpha 7 beta 7 beta 7 alpha 7 structure. We previously reported the primary structures of the 14 proteasomal subunit subfamilies in rice (Oryza sativa), representing the first set for all the subfamilies from monocot. In this study, a distinct cDNA sequence encoding the alpha1 subunit, OsPAA2, was identified. The amino acid sequence similarity between the two rice alpha1 subunits was as low as 59.6%, contrasting with those between paralogs of Arabidopsis proteasome subunit genes. The expression pattern of the OsPAA2 gene was different from that of another alpha1 gene, OsPAA1. These data suggest that OsPAA2 might play a distinct role from that of OsPAA1 in the 20S proteasome complex.

Cholesteryl ester transfer protein polymorphism associated with macroangiopathy in Japanese patients with type 2 diabetes

A polymorphism in the gene for cholesteryl ester transfer protein (CETP) has been reported to be associated with serum cholesterol levels and risk for atherosclerotic vascular diseases, and to clarify the relationship between the gene polymorphism for CETP and macroangiopathy in diabetes mellitus, a cross-sectional study was performed. The subjects of the study were182 Japanese (age: 59.6+/-8.6 years) with type 2 diabetes and no signs of renal dysfunction, 24 of whom had macroangiopathy, and 158 of whom did not. The genotype of the subjects for the TaqIB polymorphism of CETP in intron one was analyzed by using polymerase chain reaction - restriction fragment length polymorphism. Serum CETP levels were significantly higher in the B1/B1 genotype than in the other genotypes (P<0.05). The serum CETP levels were correlated with the serum LDL cholesterol levels (P<0.01), but not with the HDL cholesterol levels. Macroangiopathy was more frequently observed in subjects with the B1/B1 genotype than in the other genotypes (odds ratio=2.953, 95% confidence interval=1.250-6.977, P=0.0136). Logistic regression analysis revealed that the CETP genotype was independently associated with macroangiopathy. The exact mechanism underlying the association remains unknown, but differences in serum CETP levels may be involved.

Effects of n-3 polyunsaturated fatty acids and vitamin E on colonic mucosal leukotriene generation, lipid peroxidation, and microcirculation in rats with experimental colitis

AIMS

We investigated the effect of n-3 polyunsaturated fatty acids (PUFAs) on mucosal levels of leukotrienes (LTs) and lipid peroxide (LPO), and on mucosal microcirculation, in rats with experimental colitis induced by dextran sulfate sodium (DSS).

METHODS

We fed Wistar rats a perilla oil-enriched diet containing alpha-linolenic acid (63.2% of total fatty acids) with various doses of vitamin E for 4 weeks, with 4% DSS added to the drinking water during the last week. Control rats were fed a diet produced from soybean oil containing alpha-linolenic acid (5.1% of total fatty acids). Colonic mucosal blood flow was measured with a laser Doppler flowmeter.

RESULTS

The mucosal level of arachidonic acid was significantly lower and that of eicosapentaenoic acid was significantly higher in the experimental group. The mucosal level of LPO in the experimental group fed a trace or ordinary dose of vitamin E was significantly higher than that of the controls. The production of LTB(4) and LTC(4) from the colonic mucosa in the experimental group was significantly lower than that in controls. However, only the experimental group fed a vitamin E dose 4-fold higher than that given to the controls showed a significant increase in mucosal blood flow.

CONCLUSION

These results suggest that n-3 PUFAs increase mucosal blood flow by inhibiting LT production when there is sufficient vitamin E to inhibit lipid peroxidation in rats with experimental colitis.

Monoclonal antibody against vascular cell adhesion molecule-1 inhibits neointimal formation after periadventitial carotid artery injury in genetically hypercholesterolemic mice

Vascular cell adhesion molecule (VCAM)-1 is induced in smooth muscle cells after arterial injury, in which it has been implicated in the recruitment of inflammatory cells to the site of injury. To investigate the effect of hypercholesterolemia on VCAM-1 induction after injury and the role of VCAM-1 in neointimal response to injury, we injured the carotid artery of wild-type and apolipoprotein E null (KO) mice fed normal and high cholesterol chow. We demonstrate a graded response of VCAM-1 induction as well as monocyte/macrophage infiltration by immunohistochemistry 3 days after injury that correlated with increasing circulating cholesterol levels. Three weeks after injury, KO mice fed high cholesterol chow (KO HC group) had a significantly greater neointimal formation compared with wild-type and KO mice fed normal chow (P<0.05). Inhibition of VCAM-1 function in the KO HC group by monoclonal antibody treatment significantly reduced monocyte/macrophage infiltration and neointimal formation. There was reduced alpha-actin expression in KO HC mice 7 days after injury that was partially inhibited by VCAM-1 antibody treatment. Cell migration in an in vitro injury model was partially inhibited by monoclonal VCAM-1 antibody treatment. We propose an additional role for VCAM-1 in smooth muscle cell activation and neointimal formation after injury.

Primary structural features of the 20S proteasome subunits of rice (Oryza sativa)

The 20S proteasome is the proteolytic complex that is involved in removing abnormal proteins, and it also has other diverse biological functions. Its structure comprises 28 subunits arranged in four rings of seven subunits, and exists as a hollow cylinder. The two outer rings and two inner rings form an alpha7beta7beta7alpha7 structure, and each subunit, alpha and beta, exists as seven different types, thus giving 14 kinds of subunits. In this study, we report the primary structures of the 14 proteasomal subunit subfamilies in rice (Oryza sativa), representing the first set for all of the subunits from monocots. Amino acid sequence homology within the rice family (alpha-type: 28.9-42.1%; beta-type: 17.2-31. 9%) were lower than those between rice subunits and corresponding orthologs from Arabidopsis and yeast (alpha-type: 49.2-94.5%; beta-type: 34.8-87.7%). Structural features observed in eukaryotic proteasome subunits, i.e., alpha- or beta-type signature at the N-termini, Thr active sites in beta1, beta2 and beta5 subunits, and nuclear localization signal-like sequences in some alpha-type subunits, were shown to be conserved in rice.

Kaposi's varicelliform eruption of an elderly patient with multiple myeloma

Kaposi's varicelliform eruption (KVE) is characterized by disseminated vesiculopustules and erosions due to a herpes virus infection superimposed on a preexisting dermatosis such as atopic dermatitis. However, the occurrence of KVE in patients with multiple myeloma seems to be very rare; to our knowledge, only one such case has been reported. This report documents a second case of KVE in a patient with multiple myeloma.

Activated factor XII levels are dependent on factor XII 46C/T genotypes and factor XII zymogen levels, and are associated with vascular risk factors in patients and healthy subjects

Coagulation factor XII (FXII) is activated on contact with various biologic surfaces, including subendothelial tissues and lipoprotein particles. Thus, the plasma level of activated FXII (XIIa) might represent vascular lesions or be a marker of abnormal lipid metabolism. A 46C/T polymorphism was recently described in the FXII gene close to the ATG translation initiation codon, which was associated with inter-individual variation of plasma FXII zymogen levels. The present paper reports the association of the 46C/T polymorphism with plasma XIIa levels in apparently healthy subjects, and in patients with ischemic cerebrovascular disease (CVD) and arteriosclerosis obliterans (ASO). XIIa levels were not significantly different between patients and controls, but were strongly dependent on XII 46C/T genotypes (2.07 +/- 0.81, 1.65 +/- 0.63, and 0.93 +/- 0.41 ng/ml for C/C, C/T, and T/T genotypes, respectively; P < 0.0001). This association was evident for each group studied (P < 0.0001 for CVD and controls; P= 0.0007 for ASO). There were positive correlations between plasma FXII clotting activity and XIIa levels. In a univariate analysis, XIIa correlated with total cholesterol, triglycerides, plasminogen activator inhibitor-1, and C-reactive protein (CRP), although the presence of conventional cardiovascular risk factors (male sex, smoking, hypertension, hypercholesterolemia, diabetes) did not significantly increase XIIa. Stepwise regression analyses revealed that the XII clotting activity had the strongest association with XIIa. In conclusion, XIIa levels depended on XII 46C/T genotype and correlated with some cardiovascular risk factors. Thus, the FXII genotype should be taken into consideration for interpretation of plasma XIIa levels.

Reconstituted HDL containing human apolipoprotein A-1 reduces VCAM-1 expression and neointima formation following periadventitial cuff-induced carotid injury in apoE null mice

Arterial injury triggers an inflammatory response in part mediated by induction of adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1) and is implicated in neointimal thickening. Since HDL is known to reduce cytokine-activated VCAM-1 expression, we tested the hypothesis that VCAM-1 expression and neontimal thickening following arterial injury are inhibited by reconstituted human HDL containing plasma-derived apoA-1 (rHDL). We used the carotid cuff injury in apoE (-/-) mice fed high cholesterol. Mice received rHDL (40 mg/kg) intravenously every other day for 3 weeks. Compared to control, rHDL treatment inhibited neointima formation (0. 008 +/- 0.004 mm(2) vs. 0.037 +/- 0.019 mm(2); P < 0.01) 21 days after injury, reduced VCAM-1 expression, and decreased monocyte/macrophage infiltration as assessed by histomorphometric analysis within the first week after injury. These changes occurred without any effect on plasma total and HDL cholesterol levels as well as the arterial tissue cholesterol levels. rHDL treatment also reduced the formation of modified lipoprotein in the arterial wall compared to control within the first week after injury. This finding suggests an antioxidant effect of rHDL associated with reduced VCAM-1 expression and neointimal formation after arterial injury.

Effects of troglitazone on fat distribution in the treatment of male type 2 diabetes

We investigated the efficacy of additional administration of 400 mg troglitazone (+T), which became available as a treatment for type 2 diabetes following the demonstration of its ability to reduce insulin resistance, in combination with diet (D + T) or sulfonylurea (S + T) therapy. Body fat area as determined by computed tomographic (CT) scanning at the umbilical level, as well as several clinical and biochemical parameters of glycemic control and lipid metabolism, were compared before and after 3 months of additional treatment with troglitazone. The body mass index (BMI) tended to increase in both groups (22.7 +/- 0.6 v 23.2 +/- 0.6 kg/m2 in D + T, nonsignificant [NS]; 22.2 +/- 0.5 v 22.3 +/- 0.5 kg/m2 in S + T, NS), while it tended to decrease in the control group (only diet therapy, 23.6 +/- 0.6 v 23.1 +/- 0.8 kg/m2, NS). Mean blood pressure ([BP] 96 +/- 3 v 89 +/- 4 mm Hg, P < .05) decreased significantly in the D + T group. Changes in the glycemic and lipid profile and leptin did not reach statistical significance. The D + T group showed a significant decline in immunoreactive insulin ([IRI] 12.4 +/- 1.2 v 8.0 +/- 1.0 microU/mL, P < .05), reflecting markedly reduced insulin resistance, as well as a significant increase in plasma insulin-like growth factor-1 ([IGF-1] 175.7 +/- 14.2 v 189.8 +/- 12.6 ng/mL, P < .05). A slight weight gain was associated with a tendency for subcutaneous fat to increase, while visceral fat decreased in both troglitazone-treated groups. The decrease in the visceral to subcutaneous fat ratio (V/S ratio) was statistically significant in the D + T group (1.09 +/- 0.11 v 0.94 +/- 0.09, P < .05), while the V/S ratio in the control group did not change. A notable finding of this study is the difference in the response to troglitazone between subcutaneous and visceral adipose tissue. It is suggested that troglitazone may exert beneficial effects by reducing visceral fat.

[Effect of lipoprotein metabolism abnormality for intimal thickening]

Recent advances of lipoprotein metabolism abnormality were reviewed. Recombinant apolipoprotein and transgenic mice expressing high levels of apolipoproteins or apolipoprotein deficient mice produced by gene targetting technique are providing important information on effect of lipoprotein metabolism. We made novel mouse cuff injury model for transgenic mice and knock-out mice. This injury model will also provide important information on intimal thickening using transgenic mice and knock-out mouse.

A 127-kDa protein (UV-DDB) binds to the cytoplasmic domain of the Alzheimer's amyloid precursor protein

Alzheimer amyloid precursor protein (APP) is an integral membrane protein with a short cytoplasmic domain of 47 amino acids. It is hoped that identification of proteins that interact with the cytoplasmic domain will provide new insights into the physiological function of APP and, in turn, into the pathogenesis of Alzheimer's disease. To identify proteins that interact with the cytoplasmic domain of APP, we employed affinity chromatography using an immobilized synthetic peptide corresponding to residues 645-694 of APP695 and identified a protein of approximately 130 kDa in rat brain cytosol. Amino acid sequencing of the protein revealed the protein to be a rat homologue of monkey UV-DDB (UV-damaged DNA-binding protein, calculated molecular mass of 127 kDa). UV-DDB/p127 co-immunoprecipitated with APP using an anti-APP antibody from PC12 cell lysates. APP also co-immunoprecipitated with UV-DDB/p127 using an anti-UV-DDB/p127 antibody. These results indicate that UV-DDB/p127, which is present in the cytosolic fraction, forms a complex with APP through its cytoplasmic domain. In vitro binding experiments using a glutathione S-transferase-APP cytoplasmic domain fusion protein and several mutants indicated that the YENPTY motif within the APP cytoplasmic domain, which is important in the internalization of APP and amyloid beta protein secretion, may be involved in the interaction between UV-DDB/p127 and APP.

Interaction of a neuron-specific protein containing PDZ domains with Alzheimer's amyloid precursor protein

A novel protein, human X11-like (human X11L), contains a phosphotyrosine interaction (PI) domain and two PDZ domains and displays 55.2% amino acid homology with the human X11 (human X11). The PI domain of human X11L interacts with a sequence containing the NPXY motif found in the cytoplasmic domain of Alzheimer's amyloid precursor protein. A construct lacking the carboxyl-terminal domain, which comprises two PDZ domains (N + PI), enhances PI binding to APP, whereas another construct lacking an amino-terminal domain relative to PI domain (PI + C) suppresses PI binding to APP. Overexpression of full-length human X11L (N + PI + C) in cells that express APP695 stably decreased the secretion of Abeta40 but not that of Abeta42. However, overexpression of the PI domain alone and the N + PI construct in cells did not affect the secretion of Abeta despite their ability to bind to the cytoplasmic domain of Alzheimer's amyloid precursor protein. These observations suggest that the amino-terminal domain regulates PI binding to APP and that the carboxyl-terminal domain containing PDZ motifs is essential to modulate APP processing. Because expression of the human X11L gene is specific to brain, the present observations should contribute to shedding light on the molecular mechanism of APP processing in Alzheimer's disease.

Chronic oral antigen exposure induces lymphocyte migration in anaphylactic mouse intestine

Persistent diarrhea, vomiting, and dehydration are symptoms often seen in patients suffering from food allergy after chronic antigen exposure; however, the precise mechanisms involved have not been well defined. In an effort to clarify the mechanisms of the chronic intestinal changes attributable to genuine IgE-mediated anaphylactic reactions induced by orally administered antigen, a mouse model was established by s.c. implantation of a murine hybridoma capable of producing monoclonal anti-trinitrophenyl IgE antibody, and the morphologic and immunologic changes occurring in the intestine upon chronic antigen exposure were investigated. In the early stage after ingestion of the antigen, diarrhea and noticeable infiltration of mast cells as well as eosinophils into the lamina propria were observed. A substantial increase in serum histamine levels as well as an increase in leukotriene C4 synthesis in the jejunal mucosa were observed 1 h after antigen challenge. Also, the synthesis of leukotriene B4 was significantly elevated for up to 9 h after antigen challenge. The expression of both intercellular adhesion molecule-1 (ICAM-1) on mucosal vascular endothelial cells and IAd on epithelial cells was markedly enhanced, and noticeable infiltration of eosinophils and lymphocytes was also confirmed in the mouse model after chronic antigen exposure. These findings suggest that oral antigen exposure induces anaphylactic reactions in the intestine mediated by mast cells and eosinophils in response to the IgE-antigen complex in the early phase, and also induces lymphocyte migration after chronic antigen exposure.

Improved hatching for in vitro quail embryo culture using surrogate eggshell and artificial vessel

The establishment of avian embryonic culture is important both for the analysis of the developmental process and the establishment of transgenic chickens that produce useful biological materials in eggs. However, the hatchability of cultured embryos has been approximately 50%. We identified that the low rate of hatchability of cultured embryos was caused by limited oxygen and calcium availability. In quail embryo culture using chicken eggshell as a culture vessel, viability in the middle stage of culture was improved and 30% of embryos were hatched by oxygen enrichment. Furthermore, hatchability increased to 80% by supplementation with calcium lactate in addition to oxygen aeration. In the present study, a fully artificial vessel for quail embryo culture was designed using a gas-permeable Teflon membrane. By the addition of fine eggshell powder and calcium lactate, quail embryos grew and developed normally, and 43% of embryos hatched. Although the hatchability was lower than that of cultures using a surrogate eggshell, we achieved in hatching an avian embryo using a fully artificial vessel.

Short-chain fatty acids regulate IGF-binding protein secretion by intestinal epithelial cells

Gastrointestinal epithelial cells secrete insulin-like growth factor (IGF)-binding proteins (IGFBPs), which modulate the actions of IGFs on cell proliferation and differentiation. Short-chain fatty acids are bacterial metabolites from unabsorbed carbohydrate (including fiber). We hypothesized that they may alter the pattern of IGFBPs secreted by epithelial cells as part of a wider phenomenon by which luminal molecules regulate gastrointestinal epithelial cell signaling. The intestinal epithelial cell line, Caco-2, predominantly secretes IGFBP-3; however, butyrate increased the secretion of IGFBP-2 in a dose-dependent and reversible manner. Butyrate decreased the secretion of IGFBP-3. Butyrate altered only the synthesis and not the cell sorting of IGFBPs because 1) the secretion of IGFBPs remained polarized despite changes in their rates of production, and 2) IGFBP secretion corresponded to mRNA accumulation. The ability of short-chain fatty acids or the fungicide trichostatin A to stimulate IGFBP-2 correlated with their actions on histone acetylation. In conclusion, intestinal epithelial cells respond to short-chain fatty acids by altering secretion of IGFBPs.

Characteristic epiluminescent microscopic features of early malignant melanoma on glabrous skin. A videomicroscopic analysis

OBJECTIVE

To investigate the characteristic epiluminescent microscopic features of early lesions of malignant melanoma affecting glabrous skin, which is the most prevalent site of the neoplasm in nonwhite populations.

DESIGN

The epiluminescent microscopic features of various kinds of melanocytic lesions affecting glabrous skin were investigated using a videomicroscope. All the diagnoses were determined clinically and histopathologically using the standard criteria.

SETTING

A dermatology clinic at a university hospital.

PATIENTS

The following 130 melanocytic lesions consecutively diagnosed at our department were examined: 16 lesions of acral lentiginous melanoma, 6 lesions of malignant melanoma in situ, and 108 lesions of benign melanocytic nevus (acquired or congenital).

MAIN OUTCOME MEASURE

The incidence of each characteristic epiluminescent feature was compared among disease categories.

RESULTS

On epiluminescent microscopy, malignant melanoma in situ and the macular portions of invasive malignant melanoma showed accentuated pigmentation on the ridges of the skin markings, which are arranged in parallel patterns on glabrous skin. This "parallel ridge pattern" was found in 5 (83%) of 6 lesions of malignant melanoma in situ and in 15 (94%) of 16 lesions of malignant melanoma. The parallel ridge pattern was rarely found in the lesions of benign melanocytic nevus. Most benign melanocytic nevi showed 1 of the following 3 typical epiluminescent patterns: (1) a parallel furrow pattern exhibiting pigmentation on the parallel sulci of [he skin markings (54%), (2) a latticelike pattern (21%), and (3) a fibrillar pattern showing filamentous or meshlike pigmentation (15%). The remaining 11 benign nevi (10%) showed a nontypical pattern.

CONCLUSION

Because epiluminescent microscopic features of early malignant melanoma on glabrous skin are characteristic, we can effectively detect early lesions using this noninvasive method.

Reducing cell membrane n-6 fatty acids attenuate mucosal damage in food-sensitive enteropathy in mice

Mucosal damage is commonly observed in food-sensitive enteropathy in infants, and the generation of leukotrienes is involved in the pathogenesis of this enteropathy. Because supplementing n-3 fatty acids is known to modify the production of leukotrienes, we investigated whether a change of dietary fatty acid composition affects leukotriene synthesis and food hypersensitivity reactions in the intestine by using a mouse model of food-sensitive enteropathy. The model was prepared by feeding ovalbumin to BALB/c mice after intraperitoneal injection of cyclophosphamide. Diets were prepared from soybean oil (control), perilla oil, lard, corn oil, and 0.125 volume of corn oil (low fat diet) and given to mice for 4 wk. Villous heights, crypt depths, leukotriene B4 and C4 production in the intestine were measured. Crypt hyperplasia and villous atrophy were severer in the corn oil-fed group than those of control group, whereas mucosal damage in the perilla oil and low fat diet groups was minimal. In the corn oil-fed group, red blood cell membrane levels of n-3 fatty acids were lower than the control, and the synthesis of leukotrienes was highest among all groups. In the perilla oil and low fat diet groups, n-6 fatty acids were lower than those of control group and leukotriene production was significantly suppressed. These results indicate that reducing cell membrane levels of n-6 fatty acids by feeding less n-6 fatty acids or supplementing n-3 fatty acids, is important to suppress leukotriene biosynthesis for prevention from mucosal damage in food-sensitive enteropathy.

Growth factors in breast milk and their effect on gastrointestinal development

Breast milk contains various biologically active factors including, hormones, peptide growth factors, and cytokines. Epidermal growth factor (EGF) and insulinlike growth factor-I (IGF-I) are two of the major milk-derived peptide growth factors. Colostrum contains higher levels of these growth factors than mature milk does, and, these factors are relatively resistant to proteolysis and stable in the G-I tract. There are specific receptors found in G-I mucosa. Luminal EGF and IGF-I stimulate growth and development of gastrointestinal tract. Intestinal epithelial Caco-2 cells are a good model for studying physiological roles of exogenous growth factors in the G-I development. Effect of EGF and IGF-I on proliferation, differentiation, and IGF-binding protein (IGFBP) production of intestinal Caco-2 cells were studied. Both EGF and IGF-I increased cell proliferation in dose dependent manner. The number of IGF-I receptors on Caco-2 cells increased after differentiation, in contrast to EGF binding which was reported to decrease. Caco-2 cells produced at least three IGFBPs, namely IGFBP-2, -3, and -4. The profile of these IGFBPs varied with differentiation. Secretion of IGFBP-2 and -3 increased with differentiation, but IGFBP-4 diminished. IGF-I stimulated mainly IGFBP-3 production, while EGF stimulated predominantly IGFBP-4. The effects of IGF-I and EGF on IGFBP secretion diminished with increasing cell differentiation. Thus, the interaction between intestinal epithelial cells and extrinsic growth factors are complex and the stage of differentiation is an important determinant of this phenomenon.

The estimated incidence of cystic fibrosis in Japan

BACKGROUND

It is believed that the incidence of cystic fibrosis (CF) among Asiatic races, including the Japanese, is very rare. This epidemiological study was carried out to investigate the incidence of CF in Japan.

METHODS

We collected literature describing CF cases among pure Japanese and found 124 cases reported as CF during the 43 years from 1951, when the first case was reported, to 1993. Only 104 cases (57 male and 47 female patients) of 124 cases met our diagnostic criteria.

RESULTS

A simple calculation based on the number of reported CF cases and of live births after 1980 suggested that the incidence of CF is about 1 in 350,000 in the Japanese population. Twenty-nine (27.9% of the total) of 30 patients diagnosed in the neonatal period presented symptoms of meconium ileus, an incidence higher than that reported for the white population.

CONCLUSIONS

Our study results suggest that the incidence of CF in the Japanese population is even rarer than had been estimated before and that there is a genetic difference between northern European and Japanese populations.

A case of infantile Dubin-Johnson syndrome with high CT attenuation in the liver

We report a case of Dubin-Johnson syndrome (DJS) with severe infantile cholestasis and elevated computed tomography (CT) attenuation of the liver. Increased levels of urinary coproporphyrin I were found as well as pigment granules in the hepatocytes and hepatosteatosis. The CT attenuation was markedly higher in the liver of this patient at the ages of 3 and 7 months than in the spleen or kidneys. This high attenuation may be a finding specific to infantile DJS and, therefore, abdominal CT may be helpful in the diagnosis.

Food antigen activates intraepithelial and lamina propria lymphocytes in food-sensitive enteropathy in mice

Morphologic and immunologic changes in the gut mucosa of food-hypersensitive mice, from a study model generated by feeding ovalbumin (OVA) to female BALB/c mice after intraperitoneal injection of cyclophosphamide (CY), were investigated in an effort to clarify the mechanisms of food-sensitive enteropathy. Villous atrophy, crypt hyperplasia, and increased numbers of intraepithelial lymphocytes (IEL) were confirmed in the antigen-challenged OVA-sensitive mice as seen in food-sensitive enteropathy in humans, whereas no significant morphologic changes were observed in the nontreated control group or groups treated with OVA or CY alone. IEL and lamina propria lymphocytes (LPL) were isolated from the intestinal mucosa before and after the antigen challenge, and surface markers were analyzed by FACScan. After the antigen challenge, the numbers of CD8+ cells increased among the IEL, and the occurrence of both CD4+ and CD8+ cells increased among the LPL. The numbers of Thy-1+ cells and TCR- alpha/beta + cells increased among both the IEL and LPL, and LFA-1 expression was enhanced in both of these lymphocyte populations. The proliferative response of IEL and LPL to OVA increased in a dose-dependent manner after the antigen challenge in the OVA-sensitive mouse model. These results indicate that IEL and LPL, possibly those that have migrated from peripheral blood, are activated by orally administered antigens and cause mucosal damage in the food-sensitive enteropathy.

Microbiologic studies on the small intestine in Kawasaki disease

In an attempt to elucidate the etiology of Kawasaki disease (KD), the microflora of the small intestine was investigated in 15 Japanese KD patients. The range of bacterial species adhering to the lumen of the jejunum of KD patients was quite different from that of controls. A wider variety of bacteria was isolated from jejunal biopsies in the acute phase of KD as compared with those from control children. Gram-positive cocci were isolated from KD patients predominantly. Notably, five kinds of streptococci and two kinds of staphylococci were isolated only from KD patients. Further investigation of the microflora of the small intestine of KD patients may provide clues to clarify the pathogenesis of this disease.

Selective increase of V beta 2+ T cells in the small intestinal mucosa in Kawasaki disease

The current study tested the hypothesis that the gastrointestinal tract could be one of the primary sites of entry for etiologic agents in Kawasaki disease (KD). In an attempt to elucidate the pathogenic role of certain superantigenic agents in KD, T cell receptor V beta expression by T cells in the small intestinal mucosa of KD patients was investigated using MAb on frozen tissue sections. Twelve Japanese patients with KD and eight controls were enrolled in the study. The numbers of cells stained by an immunofluorescence from each study group were counted and analyzed statistically by the t test. The occurrence of V beta 2+ T cells was found to be selectively increased in the small intestinal mucosa of patients in the acute phase of KD compared with controls (p < 0.01). In our previous study, five kinds of streptococci and two kinds of staphylococci, not detected in control patients, were isolated from the lumen of the jejunum of KD patients. These data suggest that the increased occurrence of V beta 2+ T cells in the jejunal mucosa of KD patients may be caused by exotoxins acting as superantigens produced by bacteria colonizing the small intestinal mucosa of these patients.

Patterns of 24 h intragastric acidity in duodenal ulcers in children: the importance of monitoring and inhibiting nocturnal acidity

The objective of this study was to compare the gastric acidity patterns of patients with duodenal ulcers and normal children. Eight patients with duodenal ulcer had their intragastric pH monitored for two consecutive 24 h periods using intragastric glass electrodes. The first 24 h period elucidated pH patterns in the absence of treatment and the second period evaluated the acid suppressive effect of 15 mg/kg of cimetidine when given in three divided doses. Results showed that the ulcer patients were hyperacidic, particularly at midnight. This finding was in marked contrast to the results obtained in the study of normal controls. The mean pH of normal children was above 3 around midnight. This phenomenon is known as intragastric pH inversion. The mean pH 3 time (the cumulative duration of the time for which gastric pH is maintained at > or = pH 3) was significantly shorter in patients with ulcers. However, pH 3 time of these patients significantly increased throughout the 24 h recording period during the daytime and at night after the introduction of cimetidine. This resulted in an induction of apparent nocturnal intragastric pH inversion for the ulcer patients. This study demonstrates the usefulness of 24 h continuous intragastric pH monitoring in children. The data showed that there was a pattern of gastric hyperacidity in pediatric ulcer patients which is clearly distinct from that of normal children, particularly in the patterns occurring at midnight. Cimetidine at 15 mg/kg per day in three divided doses was effective in suppressing secretion even at night.

In vivo observation of magnified features of pigmented lesions on volar skin using video macroscope. Usefulness of epiluminescence techniques in clinical diagnosis

BACKGROUND AND DESIGN

In vivo epiluminescence microscopy is now used as a useful noninvasive method for determining clinical diagnosis of pigmented skin lesions. Until now, however, pigmented lesions on the volar skin have been hardly studied with this method. In the present epiluminescent study, various kinds of pigmented lesions on the volar skin were extensively investigated by means of video macroscope, a newly developed electronic device with a higher magnification power, and correlation between the magnified features and histopathologic findings was evaluated.

RESULTS

Magnified features of most lesions of acquired or congenital melanocytic nevus on the volar skin were classified into the following three typical patterns: (1) a parallel pattern formed by pigmented parallel lines corresponding to the furrows of the skin markings, (2) a latticelike pattern composed of pigmented lines along and across the furrows of the skin markings, and (3) a fibrillar pattern formed by densely packed, fibrillar pigmented lines arranged in the direction crossing the furrows. In contrast, macular or plaque portions of acral lentiginous melanoma exhibited disorderly arranged, irregular pigment patterns, mainly affecting the ridges of the skin markings. In addition, brown globules of various shades and many black dots of variable sizes were often observed and, on the margin of the lesions, pseudopods and/or the "serrated" pattern were detected. Cutaneous hemorrhagic macule and so-called black heel showed highly specific features and thus could be easily diagnosed with video macroscopy.

CONCLUSION

Video macroscope proved to be a very useful instrument for the diagnosis of pigmented lesions on the volar skin.

Differentiation and polarity alter the binding of IGF-I to human intestinal epithelial (Caco-2) cells

This study examined whether insulin-like growth factor-I (IGF-I) bound to specific functioning IGF receptors on the surface of Caco-2 cells and how this binding was affected by the differentiation and polarity of these cells. IGF-I, which increased cell proliferation in a dose-dependent manner, bound to a specific receptor on the surface of Caco-2 cells. Affinity cross-linking with labeled IGF-I followed by reducing sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed M(r)s at 135,000, 270,000 and 355,000 bands, which was inhibited by unlabeled IGF-I. A Scatchard analysis of radioligand-receptor binding showed the presence of a single class of receptors with high affinity for IGF-I. This class of receptors was specific for IGF-I, the affinity of IGF-I to the receptor being four and 150 times greater than IGF-II and insulin, respectively. There was no difference in the affinity of IGF-I to type 1 IGF receptors between less-differentiated [dissociation constant (Kd) = 3.81 nM] and well-differentiated cells (Kd = 3.78 nM); however, well-differentiated cells showed a 2.4-fold higher maximum number of binding sites (Bmax) than less-differentiated cells (3.45 vs. 1.44 x 10(4) sites/cell), indicating an increase in the density of IGF-I receptors with differentiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Helicobacter pylori colonization in children with peptic ulcer disease. III. Diagnostic value of the 13C-urea breath test to detect gastric H. pylori colonization

The efficiency of the 13C-Urea Breath Test (13C-UBT) for the detection of Helicobacter pylori colonization in gastric mucosa was evaluated. The 13C-UBT was performed in five pediatric and six adult subjects who had had upper gastrointestinal endoscopy within 2 weeks. H. pylori colonization was confirmed in two pediatric and three adult subjects with peptic ulcer combined with antral gastritis, by histological examination of antral biopsy specimens. When an individual with H. pylori colonization ingested a solution containing 13C-urea, a significant amount of 13CO2 appeared in the respiratory CO2 within 10 min. The mean cumulative percentage dose of 13C recovered in the breath over 30 min in the cases with H. pylori colonization was significantly higher than that in those who were not colonized (4.91 vs 0.41, P < 0.001). In addition, the effect of antibiotic on the eradication of H. pylori from gastric mucosa was monitored by 13C-UBT in two cases. The values of cumulative percentage dose of 13C over 30 min fell to the same levels as those observed in H. pylori negative subjects after just 2 weeks treatment with amoxicillin; however, positive results were obtained again 1 month after the withdrawal of amoxicillin. In summary, 13C-UBT is a simple, reliable, non-invasive method in the diagnosis of gastric H. pylori colonization especially for pediatric patients.

Quantitative analysis and immunohistochemical studies on small intestinal mucosa of food-sensitive enteropathy

Quantitative analysis and immunohistochemical studies of small intestinal mucosa were performed to investigate the mechanism of mucosal damage in 10 patients with food-sensitive enteropathy. Jejunal biopsy specimens were taken before and after treatment and after clinical relapse following a challenge test. The low villous height of untreated patients normalized after introduction of an elimination diet but declined again to subnormal level after a challenge test. Several other types of cells were significantly increased in the untreated patients in comparison to controls. These included HLA-DR+ (DR+) CD4+ cells in the lamina propria and intraepithelial CD8+ cells. Moreover, those cell patterns, such as increased DR+ CD4+ cells and CD8+ cells, normalized with treatment but regressed to pretreatment levels when the patients were challenged. These findings suggest that activated CD4+ cells in the lamina propria of the small intestinal mucosa, probably by releasing cytokines, may play an important role in contributing to mucosal damage in patients with food-sensitive enteropathy.

Iron saturation alters the effect of lactoferrin on the proliferation and differentiation of human enterocytes (Caco-2 cells)

Recent studies have indicated that lactoferrin may act as a cell mitogen. The effect of human and bovine lactoferrins on the proliferation and differentiation of a human intestinal epithelial cell line (Caco-2) was investigated and compared with that of human transferrin. Caco-2 cells were cultured in serum-free media supplemented with both iron-unsaturated and -saturated forms of the iron-binding proteins. Cell proliferation and differentiation were evaluated by examining growth curves and measuring sucrase and alkaline phosphatase activities of brush border membrane fractions, respectively. The iron-binding status of lactoferrins and transferrin affected the proliferation of Caco-2 cells. The iron-saturated forms of human (S-hLf), bovine (S-bLf) lactoferrins and human transferrin (S-hTf) enhanced cell proliferation, while iron-unsaturated forms (U-hLf, U-bLf, and U-hTf) suppressed it. Iron-binding status also determined the effect of lactoferrin and transferrin on cellular differentiation, but this effect differed for different brush border enzymes. S-hTf enhanced sucrase activity more than S-hLF or S-bLf. Both U-hLf and U-bLf markedly suppressed sucrase activity. U-hTf suppressed alkaline phosphatase activity appreciably, while the other iron-binding proteins showed no significant effect on it. Lactoferrin and transferrin may modulate the proliferation and differentiation of intestinal epithelial cells, but their efficacy depends on their saturation with iron.

Profile of IGF-binding proteins secreted by intestinal epithelial cells changes with differentiation

Previous reports have shown that gastrointestinal epithelial cells produce insulin-like growth factor-binding proteins (IGF-BP), which modulate the actions of IGF. This study aims to examine the relationship between differentiation and IGF-BP secretion by human intestinal epithelial cells and the effect of growth factors on their production. Caco-2 cells were cultured in serum-free media. IGF-BP secretion into the incubation media was analyzed by Western ligand blotting and immunoblotting. Caco-2 cells produced IGF-BP-2, IGF-BP-3, and IGF-BP-4. Secretion of IGF-BP-2 and IGF-BP-3 increased with differentiation, but IGF-BP-4 secretion diminished. The effect of exogenous growth factors on IGF-BP secretion was maximal at earlier stages of differentiation. IGF-I stimulated mainly IGF-BP-3 production, but epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) stimulated predominantly IGF-BP-4 secretion. Adding an anti-EGF receptor antibody to block autocrine TGF-alpha activity inhibited IGF-BP-4 production but stimulated IGF-BP-2 and IGF-BP-3. In conclusion, the profile of IGF-BP secretion changes with differentiation. IGF-I and EGF (or TGF-alpha) stimulate different types of IGF-BP, with autocrine TGF-alpha activity being a factor affecting IGF-BP production during differentiation.

Helicobacter pylori colonization in children with gastritis and peptic ulcer. II. Ultrastructural change of the gastric mucosa

To evaluate the role of Helicobacter pylori in the pathogenesis of gastritis and peptic ulcer in children, ultrastructural changes of the gastric mucosa with H. pylori colonization were studied in two pediatric patients with duodenal ulcers. The study demonstrated that H. pylori: (i) colonized the mucous layer covering normal gastric epithelium; (ii) lay atop short, irregular microvilli and at the intercellular junctions of damaged cells; and (iii) adhered firmly by specific junction zone (firm connection) and loosely by filamentous appendages to the epithelial surfaces of cells which lacked evidence of a protective mucous layer. The ultrastructural changes, which become progressively worse from patterns (i) to (iii) mentioned above, suggest that these patterns represent distinct and successive stages of the infection. These findings, therefore, lend support to the notion that H. pylori infection is quite common and may relate to the pathogenesis of gastritis and peptic ulcer in children as well as in adults.

Helicobacter pylori colonization in children with gastritis and peptic ulcer. I. The colonization rate and effects of colonization on mucin content and mucosal inflammation in the antrum

The incidence of Helicobacter pylori infection and effects of H. pylori colonization on mucin content and mucosal inflammation of the antral mucosa were studied quantitatively in 55 Japanese children with suspected gastritis and peptic ulcers (aged 6-16 years, mean 12.3 years). H. pylori was detected, using Warthin-Starry stain, in nine of the 22 cases (41%) with antral histological gastritis, but in none of the 33 histologically normal cases. Five out of seven duodenal ulcer cases showed histological gastritis, and all five cases were H. pylori positive. Severity of gastritis, evaluated by means of gastritis score, was significantly higher in H. pylori positive gastritis cases than in H. pylori negative gastritis cases (5.4 +/- 1.0 vs 3.1 +/- 0.3, P < 0.001). A PAS-AB index, a proportion of the periodic acid Schiff-alcian blue (PAS-AB) positive mucin area to the total epithelial area, was significantly lower in H. pylori positive cases than in H. pylori negative cases, irrespective of the existence of histological gastritis (23.5 +/- 7.6% vs 40.4 +/- 5.5%, 43.5 +/- 4.2%, P < 0.001). The decreased mucin content of gastric mucosa is likely to lead to weakening of an important defensive factor of gastric mucosa. These findings suggest that H. pylori plays an important role in gastritis and peptic ulcers in children, especially in cases with duodenal ulcer.

Dual mechanism for the control of inducible-type NO synthase gene expression in macrophages during activation by interferon-gamma and bacterial lipopolysaccharide. Transcriptional and post-transcriptional regulation

Production of nitric oxide (NO) by macrophages is enhanced upon activation by bacterial endotoxins and cytokines mainly via an increase of the intracellular content of the inducible isoform of nitric oxide synthase (i-NOS). We have studied in detail the effect of several modulators of macrophage activity on steady state levels of i-NOS mRNA in the mouse macrophage-like cell line RAW 264.7. Bacterial lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) were found to be effective inducers of i-NOS mRNA, in accordance with their known ability to stimulate both i-NOS activity and NO production in macrophages from different sources, while TNF-alpha, IL-1, or IL-6 was ineffective in this regard. Accumulation of i-NOS mRNA in response to either LPS or IFN-gamma stimulation was accompanied by increased i-NOS gene transcription, as detected both by using a nuclear "run-on" transcription assay and by transient transfection of the cloned gene promoter in RAW 264.7 cells. Co-stimulation of the cells with both inducers resulted in higher steady state levels of i-NOS mRNA in the absence, however, of a corresponding potentiation of the rate of gene transcription. This was due primarily to a considerable effect of LPS on i-NOS mRNA stability, with prolongation of its half-life from 1-1.5 h, in the presence of IFN-gamma alone, to 4-6 h in the presence of both LPS and IFN-gamma.

Enhancement of inducible-type NO synthase gene transcription by protein synthesis inhibitors. Activation of an intracellular signal transduction pathway by low concentrations of cycloheximide

Treatment of mouse macrophage-like RAW 264.7 cells with certain protein synthesis inhibitors is followed by accumulation of the mRNA for the inducible isoform of nitric oxide synthase (i-NOS). The activity of these compounds on the i-NOS gene in RAW 264.7 cells was analyzed here in detail. Results show that both cycloheximide and anisomycin can efficiently induce i-NOS mRNA, even when used at concentrations so low (0.25 microgram/ml) to have only negligible effects on protein synthesis; puromycin, on the other hand, shows only a limited effect on i-NOS mRNA expression, detectable only when cells are treated with higher concentrations of inhibitor (25 micrograms/ml). In RAW 264.7 cells, low concentrations of cycloheximide trigger an immediate-early gene response, as indicated by induction of c-fos and JE mRNAs, and can efficiently activate transcription of transiently transfected recombinant reporter genes including either the i-NOS or the c-fos gene promoters.

In situ localization of transforming growth factor-beta 1 mRNA in the rat kidney with Masugi nephritis

Masugi nephritis was induced in rats by the administration of nephrotoxic duck serum and, in their kidneys, the distributions of transforming growth factor-beta 1 (TGF-beta 1) mRNA, TGF-beta 1, and macrophage antigenic marker were investigated. Kidney specimens were obtained at 3, 7, and 14 days after the injection. By in situ hybridization, TGF-beta 1 mRNA was found to be localized in the cells of mesangial region from the early stage of nephritis. By the immunohistochemical stainings, TGF-beta 1 was found to be localized in the cells of distal convoluted tubulus throughout the experiments and the macrophage antigenic marker was found to be localized in the occasional cells which were different from that contained TGF-beta 1 mRNA. Our data indicate that TGF-beta 1 mRNA is expressed by the resident glomerular cells and not by the migrating macrophages in rat kidney with Masugi nephritis.

Insulin-like growth factor binding protein profile secreted by human intestinal epithelial cells varies with polarity

The actions of insulin-like growth factors (IGFs) are modulated by interaction with a family of secreted binding proteins (IGFBPs). We have now demonstrated in intestinal epithelial cells (Caco-2) that the secretion of different members of this family depends on the cell surface secreting them. Polarized monolayers of cells secreted IGFBP-3 mainly into the medium adjacent to the apical surface, while IGFBP-2 was secreted predominantly through the basolateral surface. The secretion of IGFBP-1 and -4 was equivalent from both surfaces. However, administration of epidermal growth factor (EGF) induced polarized secretion of IGFBP-4 by increasing secretion from the apical surface more than from the basolateral aspect. It did not affect the polarity of the other IGFBPs. We believe that this is the first evidence that epithelial cells can interact with extrinsic agents in a polarized fashion at sites other than the membrane surface.