Y2, the smallest of the Sendai virus C proteins, is fully capable of both counteracting the antiviral action of interferons and inhibiting viral RNA synthesis

An open reading frame (ORF) overlapping the amino-terminal portion of the Sendai virus (SeV) P ORF in the +1 frame produces a nested set of carboxy-coterminal proteins, C', C, Y1, and Y2, which are referred to collectively as the C proteins. The C proteins are extremely versatile triple-role players; they counteract the antiviral action of interferons (IFNs), inhibit viral RNA synthesis, and are involved in virus assembly. In this study, we established HeLa cell lines stably expressing the C, Y1, and Y2 proteins individually and examined the capacities of these cells to circumvent the antiviral action of alpha/beta IFN (IFN-alpha/beta) and IFN-gamma and to inhibit viral transcription. The assay protocols included monitoring of IFN-alpha/beta-mediated signaling by interferon-stimulated response element-driven reporter gene expression and of the antiviral state induced by IFN-alpha/beta and IFN-gamma and measurement of reporter gene expression from an SeV minigenome, as well as quantification of SeV primary transcripts. When necessary, the activities measured were carefully normalized to the expression levels of the respective C proteins in cells. The data obtained clearly indicate that the smallest protein, Y2, was as active as the C and Y1 proteins in both counteracting the antiviral action of IFNs and inhibiting viral transcription. The data further show that intracellular transexpression of either C, Y1, or Y2 rendered HeLa cells moderately or only poorly permissive for not only wild-type SeV but also 4C(-) SeV, which expressed none of the four C proteins. On the basis of these findings, the roles of SeV C proteins in the natural life cycle are discussed.

Relationship between partial inhibition of glycolysis and hemolysis after induction of gametocytogenesis in synchronous cultures of Plasmodium falciparum

In the present study, the low molecular-weight fraction of the culture supernatant of anti-Plasmodium falciparum antibody-producing hybridoma cells (HybSL) was used in synchronous culture with P. falciparum FVO strain. When synchronous cultures were treated with HybSL solution on day 5, gametocytogenesis was also induced. Gametocytes were consistently found from the third day after treatment and reached a peak on the fourth day. An increase in pH and hemoglobin concentrations and decrease in lactate concentrations were observed on the first day after treatment. These phenomena suggested that HybSL solution partially inhibited glycolysis of erythrocytes parasitized with schizonts and resulted in hemolysis of infected erythrocytes. On the other hand, the production of gametocytes did not increase in cultures treated with HybSL solution on day 4 of synchronous cultures in which ring forms were plentiful. Most ring forms were not killed by HybSL solution and quickly developed to trophozoites and schizonts rather than gametocytes. Consequently, it is assumed that ring forms on day 4 of synchronous cultures have finished differentiation into the asexual stage. The conversion of asexual parasites to gametocytes may be triggered only when late-stage trophozoites or early-stage schizonts are treated with HybSL solution.

Accumulation of latent transforming growth factor-beta binding protein-1 and TGF beta 1 in extracellular matrix of filtering bleb and of cultured human subconjunctival fibroblasts

PURPOSE

To examine immunohistochemically whether extracellular matrix (ECM) of the filtering bleb and of cultured human subconjunctival fibroblasts contains latent TGF beta binding protein-1 (LTBP-1) and TGF beta.

METHODS

An enucleated human eye that had undergone trabeculectomy and cultured human subconjunctival fibroblasts were processed for light microscopic immunohistochemistry. Antibodies against LTBP-1, collagen types, fibrillin-1 and TGF beta s were used. TGF beta 1 was located by detecting beta 1-latency associated peptide (LAP).

RESULTS

LTBP-1, beta 1-LAP and fibrillin-1 were all located in the subepithelial ECM as well as in the basal epithelial cells of the conjunctiva over the filtering bleb. TGF beta 2 and beta 3 were immunolocated to epithelium and/or fibroblasts/keratocytes. ECM deposited in confluent fibroblast cultures was positive for beta 1-LAP, LTBP-1 and fibrillin-1, whereas sparse cells were negative.

CONCLUSIONS

LTBP-1, beta 1-LAP and fibrillin-1 are co-localized to the ECM of the filtering bleb and of cultured conjunctival fibroblasts. Both conjunctival epithelium and fibroblasts are considered to be the source of TGF beta in healing bleb. ECM secreted by in vivo and in vitro subconjunctival fibroblasts may works as a scavenger or repository of TGF beta.

Overexpression of human H-ras transgene is responsible for tumors induced by chemical carcinogens in mice

Level of human prototype H-ras transgene expression in tumors induced by chemical carcinogens (N-ethyl-N-nitrosourea and N-methyl-N-nitrosourea) was analyzed in human H-ras transgenic mice (CB6F1-TgrasH2 Jic mice). All forestomach tumors examined revealed about 2-fold overexpression of the human H-ras transgene with or without point mutation at codon 12 or codon 61. However, endogenous mouse H- and K-ras genes exhibited neither point mutation nor overexpression. These results suggested that increased levels of ras gene products in the cell played an important role in facilitating chemical carcinogenesis in transgenic mice.

Effects of dietary polyamine deficiency on Trypanosoma gambiense infection in rats

Nishimura, K., Araki, N., Ohnishi, Y., and Kozaki, S. 2001. Effects of dietary polyamine deficiency on Trypanosoma gambiense infection in rats. Experimental Parasitology 97, 95-101. A diet deficient in polyamines decreases the availability of dietary polyamines. We used rats infected with the Wellcome strain of Trypanosoma gambiense to examine the effects of polyamine-deficient chow (PDC) on trypanosome proliferation and symptoms of infection. Rats fed PDC showed limited increase of trypanosome and symptoms of infection and limited loss of body weight and anemia. Survival in these rats was prolonged. Before infection, the heparinized plasma concentration of spermidine in the PDC-fed rats was lower than that in control rats fed with standard chow. After infection, the content of spermidine in red blood cells increased in the control rats, but was only slightly increased in PDC-fed rats. The content of spermidine in the trypanosomes after infection was low in the PDC-fed rats. Decreases in the polyamine content of trypanosomes limited their increase. These observations suggest that a reduction in dietary polyamines may help in the regulation of trypanosome infection.

[Complete response of a massive hepatocellular carcinoma with lung metastasis to UFT (DPD inhibitory fluoroprymidines: DIF)]

A 77-year-old man was referred to our hospital because a periodic examination for hepatitis C cirrhosis and diabetes mellitus at a nearby clinic had revealed an elevated AFP level. Abdominal ultrasound and CT scan revealed a giant tumor in the right hepatic lobe, and a diagnosis of hepatocellular carcinoma was made with a biopsy. A pulmonary CT scan also revealed a diffuse granular shadow in the right lung field, leading to a diagnosis of multiple pulmonary metastases from the hepatocellular carcinoma. Arterial infusion chemotherapy was performed, but was ineffective. Thus, the administration of 600 mg/day of UFT was initiated. Both the AFP and PIVKA-2 levels, which had been increasing, returned to normal 3 months later. Ultrasound and CT scan showed that the hepatocellular carcinoma and lung metastatic foci had disappeared completely. The administration of UFT therefore appears promising for the treatment of hepatocelluar carcinoma and can be used safely, even with patients in poor general condition.

Risk stratification for sudden cardiac death in dilated cardiomyopathy using microvolt-level T-wave alternans

Predicting sudden cardiac death (SCD) in patients with dilated cardiomyopathy (DCM) is difficult, so the present study evaluated the efficacy of microvolt-level T-wave alternans (TWA) and compared it with conventional parameters for prospective risk stratification of SCD in patients with DCM. Eighty-two patients with DCM (53+/-15 years old, 67M/15F) underwent assessment of TWA, left ventricular end-diastolic diameter (LVDd), left ventricular ejection fraction (LVEF), signal-averaged ECG, and analysis of 24-h Holter monitoring and QT dispersion (QTd). The endpoint of the study was defined as either SCD or documented sustained ventricular tachycardia/ventricular fibrillation (SVT/VF) during the follow-up period. During an average follow-up period of 24 months, 1 patient died suddenly and 9 patients had SVT/VF. Kaplan-Meier survival analysis showed that TWA, LVEF (< or =35%), nonsustained ventricular tachycardia, and QTd (>90ms) were significant univariate risk stratifiers (p<0.005, p<0.005, p<0.005, and p<0.05, respectively). Multivariate Cox regression analysis showed that TWA and the LVEF were statistically significant independent risk stratifiers (p<0.05 and p<0.01, respectively). A combination of TWA and LVEF identified high risk DCM patients (p<0.01); TWA for the electrical substrate and the LVEF for the hemodynamic function.

Inhibitory effects of bitter melon (Momordica charantia Linn.) on bacterial mutagenesis and aberrant crypt focus formation in the rat colon

Antimutagenicity and chemopreventive activity of an 80%-ethanol extract of bitter melon (Momordica charantia Linn.) against the formation of azoxymethane (AOM)-induced aberrant crypt foci (ACF) was investigated. The bitter melon extract was nonmutagenic and inhibited the mutagenicity of heterocyclic amines 2-amino-3,4-dimethylimidazo[4,5-f]quinoline and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, and aflatoxin B1 in the Salmonella mutation assay. To examine the inhibitory effect of bitter melon on AOM-induced ACF formation, male F344 rats were fed various concentrations of the extract (0.1, 0.5, and 1.0 g/kg body weight) for five weeks during the initiation stage. One week after the administration of the plant extract, rats were subcutaneously given AOM at 15 mg/kg body weight once a week for two weeks. Three rats in each group were sacrificed 12 hr after the second AOM injection to analyze DNA adducts, O6-methylguanine (O6-meG) and N7-methylguanine in the liver and colon. The remaining rats were sacrificed 3 weeks after the second AOM injection to observe ACF. To examine the inhibitory effect of the extract on ACF formation in the postinitiation stage, rats were fed the extract at 0.1 and 1.0 g/kg body weight for 12 weeks starting two weeks after the second AOM injection. Treatment with bitter melon extract significantly inhibited ACF formation in the colon during the initiation stage and dose-dependently decreased the average of O6-meG DNA adduct in the colonic mucosa. During the postinitiation stage, bitter melon extract, at 1.0 g/kg body weight, significantly inhibited ACF formation in the colon, especially the formation of ACF with four or more crypts per focus. These findings suggest that bitter melon is a possible chemopreventive agent against colon carcinogenesis.

PCR-dot blot hybridization based on the neuraminidase-encoding gene is useful for detection of Bacteroides fragilis

Bacteroides fragilis is a Gram-negative obligate anaerobe frequently isolated from clinical specimens and sometimes causes severe septicemia in compromised hosts. Increasing interest has been shown in the enterotoxigenicity and drug resistance of B. fragilis in the field of medical microbiology. We previously reported rapid detection of this anaerobe by nested PCR targeting a neuraminidase-encoding gene nanH. In the present study, we synthesized a digoxigenin-labeled oligonucleotide probe, NH1, which is specific for nanH of B. fragilis, and we combined the hybridization assay using NH1 with the nanH-PCR to detect this anaerobe in a bacteremia model mice. In the specificity test, the oligonucleotide probe, NH1, hybridized only to amplification products from B. fragilis. PCR-dot blot hybridization based on nanH enabled detection of cells of B. fragilis in blood samples even when the number was as low as 2 x 10(3) colony-forming units/ml. These findings suggest that PCR-dot blot hybridization targeting nanH is a useful procedure for diagnosis of septicemia caused by B. fragilis when viable cells in blood cannot be detected by the traditional culture techniques.

A sigmaB-like factor responsible for carotenoid biosynthesis in Streptomyces griseus

Self-cloning experiments with a high-copy-number plasmid and Streptomyces griseus IFO13350 led to the cloning of a 11-kb DNA fragment that conferred yellow pigment production on the host. The cloned fragment contained a gene cluster for carotenoid biosynthesis, in which two polycistrons, crtE (encoding geranylgeranyl pyrophosphate synthase)-crtI (phytoene dehydrogenase)-crtB (phytoene synthase)-crtV (functionally unknown methyltransferase-like protein) and crtY (lycopene cyclase)-crtT (functionally unknown methyltransferase-like protein)-crtU (beta-carotene dehydrogenase), were present in a convergent way. Since strain IFO13350 produced no detectable amount of carotenoids, an increase in the copy number of the crt gene cluster led to production of carotenoids at a detectable level. Overexpression of the stress-responsive sigmaB-like protein CrtS from Streptomyces setonii also activated the cryptic crt genes in S. griseus and conferred pigmentation. A CrtS homologue (sigmaCrtS) in S. griseus, which was predicted by a computer-aided homology search, caused carotenogenesis to the same extent as CrtS of S. setonii, indicating that the two sigmaB-like proteins were functionally the same. Yellow pigment production by S. griseus containing crtS under the control of a strong promoter on a high-copy-number plasmid resulted from activation of transcription of the crt genes, because overexpression of sigmaCrtS in S. griseus led to transcriptional activation of the promoters in front of crtE and crtY. S1 nuclease mapping showed that crtS itself was transcribed at a low level under the laboratory conditions, which may account for undetectable production of carotenoids. The crt genes were suggested to locate very near one end of the linear chromosome, since they were completely deleted in mutant HH1 having large deletions at both ends. The gene organization of crt in S. griseus is similar to that in S. coelicolor A3(2) where the whole crt gene set is near one end of the chromosome.

Quantitative changes of calcium, phosphorus, and magnesium in common iliac arteries with aging

To elucidate the mechanism of element accumulations in the arteries with aging, the authors investigated the mass ratios among calcium, phosphorus, and magnesium in the common iliac arteries by inductively coupled plasma-atomic emission spectrometry. The subjects consisted of 16 men and 8 women, ranging in age from 65 to 93 yr. It was found that there were extremely significant correlations between calcium and phosphorus contents, between calcium and magnesium contents, and between phosphorus and magnesium contents in the common iliac arteries. In regard to the mass ratio, although the mass ratio of calcium to phosphorus was almost constant, the mass ratios of magnesium to calcium and phosphorus were different at early and advanced stages of the accumulation of calcium and phosphorus. It was found that both the mass ratios of magnesium to calcium and phosphorus were higher at an early stage of the accumulation of calcium and phosphorus in the arteries than at an advanced stage of the accumulation.

A calcium-binding protein with four EF-hand motifs in Streptomyces ambofaciens

A gene (cabA) encoding a calcium-binding protein was cloned from Streptomyces ambofaciens. CabA was 180 amino acid residues long and contained four typical EF-hand motifs bearing high sequence similarity to the calcium-binding sites in calmodulin. Consistent with this, CabA showed distinct calcium-binding activity, comparable to bovine brain calmodulin. cabA was transcribed throughout growth, as found by S1 nuclease mapping. Southern hybridization experiments showed that a single copy of cabA was present in various Streptomyces species. A hypothetical relationship between CabA and aerial mycelium formation in this strain was examined, since S. ambofaciens showed calcium-dependent aerial mycelium formation. However, disruption of cabA or overexpression of cabA in S. ambofaciens caused no detectable phenotypic changes.

Extracellular matrix components in a case of retrocorneal membrane associated with syphilitic interstitial keratitis

PURPOSE

A web-like retrocorneal membrane (RCM) is an uncommon complication of chronic syphilitic interstitial keratitis. Extracellular matrix components have not yet been defined in this structure, although previous histologic examinations have suggested the presence of collagen. We examined the presence and distribution of extracellular matrix components in a patient with an RCM.

METHODS

A specimen of the opaque cornea affected by syphilitic interstitial keratitis with RCM formation was obtained during penetrating keratoplasty in a 62-year-old woman and was evaluated by histology, immunohistochemistry, and scanning electron microscopy (SEM). Antibodies against collagen types I, III, and IV; fibronectin; vimentin; alpha-smooth muscle actin (alpha-SMA); heat shock protein 47 (Hsp 47); proliferating cell nuclear antigen (PCNA); and Ki67 were used.

RESULTS

Histologic analysis detected multiple concentric, acellular layers positive for collagen types I, III, and IV. The corneal endothelial cells (CECs) were positive for vimentin, collagen I, fibronectin, and Hsp 47 but not for alpha-SMA. Furthermore, the CECs were negative for PCNA and Ki67, indicating that they were not proliferating. SEM revealed the RCM was covered by CECs with a fibroblastic appearance.

CONCLUSION

RCM associated with syphilitic interstitial keratitis contained collagen types I, III, and IV and fibroblast-like CECs. These CECs may secrete the extracellular matrix components found in the RCM. Hsp 47 up-regulation in the CECs may play an important role in RCM formation. These findings provide further insights into the phenotypic modulation of CECs.

Estrogenic influences of estradiol-17 beta, p-nonylphenol and bis-phenol-A on Japanese medaka (Oryzias latipes) at detected environmental concentrations

Mature male medaka were continuously exposed to 0.005, 0.0-5 or 1.0 ppb of estradiol-17 beta (E2 or 0.1, 10 or 100 ppb of p-nonylphenol (NP) or bis-phenol-A (BPA). Female-specific proteins (Fsp) were induced in medaka exposed to 0.005 ppb of E2, 0.1 ppb of NP, or 10 ppb of BPA. Concentrations of 0.005 pbb of E2 and 0.1 ppb of NP corresponded to concentrations of these chemicals detected in river water in Japan. The abilities of the 3 chemicals to induce Fsp were E2 > NP > BPA. Embryonic medaka were exposed to E2, NP and BPA under conditions of static-renewal for 200-230 days until pre-maturity. Survival ratios of medaka exposed to E2 and NP declined in concentrations more than 25 ppb and 50 ppb, respectively. The groups of medaka exposed to E2 had individuals with testis-ova or abnormal gonad. There was no male in exposure to 1.0 ppb E2. When exposed to 100 ppb of NP or BPA, abnormal gonad was also detected. Abnormal anal fin (female-like) was observed in male exposed to 100 ppb of NP. The LC50 values for each of the 3 chemicals were much higher than the concentrations detected in water in the environment--the 3 chemicals were considered to have no lethal effect on medaka in aquatic environments. However, exposures to E2 or NP at environmental concentrations induced Fsp. BPA also had the ability to affect medaka as an environmental estrogen, although its extrogenic activity was weaker than that of E2 or NP.

Characterization of the mutations of the K-ras, p53, p16, and SMAD4 genes in 15 human pancreatic cancer cell lines

Human pancreatic cancer is one of the most malignant diseases in the world. In order to save patients with pancreatic cancer, it is necessary to develop novel methods for treatment. For such a purpose, a series of well-characterized cancer cell lines are of great help for in vitro studies that are generally the first step in approaching the invention of novel methods for treatment. In the present study, we analyzed 15 human pancreatic cancer cell lines for genetic alterations of the K-ras, p53, p16, and SMAD4 genes, which are very frequent targets for mutation in pancreatic cancer; these cell lines are useful resources in cancer research.

Intravascular ultrasound imaging before and after angioplasty for stenosis of arteriovenous fistulae in haemodialysis patients

BACKGROUND

Complications of haemodialysis vascular access have emerged as a major cause of patient morbidity. Intravascular ultrasound imaging is a new technical modality providing visualization of the vessel lumen and wall structure in a cross-sectional fashion. Percutaneous transluminal angioplasty has long been used in the treatment of stenoses of arteriovenous fistulae. However, there is no detailed quantitative information on the stenotic lesion and the morphological change by angioplasty.

METHODS

Intravascular ultrasound studies were performed in 40 haemodialysis patients with 63 stenoses in arteriovenous fistulae who had percutaneous transluminal angioplasty. The patients were qualitatively and quantitatively evaluated for echogenic patterns and morphological changes before and after angioplasty.

RESULTS

Morphological plaque features in stenotic lesions were classified as 37 soft (58%), five hard (8%), 20 mixed (32%), and one calcified sites. Plaque fractures after angioplasty were detected in 45/63 (71%) instances. The lumen cross-sectional area was found to be dilated approximately threefold (from 3.8+/-2.4 to 11.1+/-4.5 mm(2)) and the external elastic membrane cross-sectional area was dilated approximately twofold (from 11.1+/-5.3 to 19.8+/-8.1 mm(2)) after angioplasty.

CONCLUSION

These results indicate that intravascular ultrasound allows both qualitative and quantitative assessments of arteriovenous fistulae in haemodialysis patients. The results further suggest that the mechanism of expansion of arteriovenous fistulae stenoses by percutaneous transluminal angioplasty involves stretching of the vessel wall as well as plaque fractures.

Induction of drug metabolism-related enzymes by methylcholanthrene and phenobarbital in transgenic mice carrying human prototype c-Ha-ras gene and their wild type littermates

Transgenic mice hemizygously carrying human c-Ha-ras proto-oncogene, Tg-rasH2 show very sensitive and facilitated carcinogenicity to various carcinogens. In this study, activities of certain enzymes related to drug metabolism and energy metabolism were measured in microsome and cytosol fractions of livers of Tg-rasH2 mice and their wild type littermates with both sexes treated with 3-methylcholanthrene (MC) and phenobarbital (PB). Aminopyrine N-demethylase activities increased significantly in livers of all mice treated with PB. MC and PB treatments induced significant increases in activities of UDP-glucuronosyltransferase and S-adenosyl homocysteinase compared to those in the non-treated groups in microsome fractions from all mice. In cytosol fractions of livers of all mice, glutathione S-transferase activity was significantly induced in the PB treated groups. There were no significant differences in activities of lactate dehydrogenase, glucose 6-phosphate dehydrogenase, pyruvate kinase and glucose 6-phosphatase related to energy metabolism in livers and kidneys among all mice. Tg-rasH2 mice showed stable activities of enzymes related to drug detoxication and energy metabolism similar to those of non-transgenic mice. These results suggest that the human c-Ha-ras transgene may not affect drug metabolism-related enzymes, and the facilitated carcinogenic response in the Tg-rasH2 mouse is not due to these enzymatic disorders.

Simultaneous accumulation of calcium, phosphorus, and magnesium in various human arteries

To elucidate compositional changes of the arteries with aging, the authors investigated the relationships among average contents of calcium, phosphorus, sulfur, and magnesium in the arteries by inductively coupled plasma-atomic emission spectrometry. The arteries used were the thoracic and abdominal aortas, coronary, common carotid, anterior, middle and posterior cerebral, vertebral, basilar, internal thoracic, axillary, radial, truncus celiacus, common, internal and external iliac, femoral, popliteal, and umbilical arteries. It was found that high correlations were found between the average contents of calcium and phosphorus, between the average contents of calcium and magnesium, and between the average contents of phosphorus and magnesium in the arteries, but not between the average contents of sulfur and the other elements. These correlations revealed that as the content of calcium and phosphorus increased in the arteries, the magnesium content increased simultaneously in the arteries, but the sulfur content did not. It is likely that magnesium forms compounds with phosphorus in the arteries.

Accumulation of calcium and phosphorus accompanied by increase of magnesium and decrease of sulfur in human arteries

To elucidate the accumulation of elements in the arteries with aging, the authors investigated age-related changes of elements in human arteries, such as the thoracic aorta, femoral, basilar, coronary, radial, and common iliac arteries by inductively coupled plasma-atomic emission spectrometry. The subjects consisted of 17 men and 9 women, ranging in age from 55 to 92 yr in the cases of the five arteries, except for the common iliac arteries, in which the subjects consisted of 16 men and 8 women, ranging in age from 65 to 93 yr. It was found that there were significantly direct correlations between calcium and phosphorus contents and between calcium and magnesium contents in all of the six arteries: thoracic aorta, femoral, basilar, coronary, radial, and common iliac arteries. Significantly direct correlations were also found between phosphorus and magnesium contents in the five arteries, except for the basilar artery. In contrast, significantly inverse correlations were found between calcium and sulfur contents and between phosphorus and sulfur contents in the four arteries, except for the coronary and radial arteries. These revealed that the accumulation of calcium and phosphorus in the arteries was accompanied by an increase of magnesium in the arteries and by a decrease of sulfur in the arteries.

Disappearance of desmosomal components in rat corneal epithelium during wound healing

PURPOSE

Epithelial migration is essential for healing of the ablated corneal epithelium. To reveal the mechanism which enables the corneal epithelial cells to dissociate during migration, we investigated the immunolocalization of the components of the desmosome, which is the main constituent of the intercellular junction attaching the intermediate filaments to the cell surface, desmoplakin 1, desmoglein and plakoglobin, in the corneal epithelium during wound healing in rats.

METHODS

Under general anesthesia with ether inhalation, Wistar rats (n = 48) underwent removal of the central corneal epithelium of one eye with a small trephine and a scalpel. After various intervals of healing (5 min; 1, 3, 6, 9, 12, 24, 48 h; 1 and 2 weeks), the animals were killed and the affected eye was excised. Cryosections of each anterior segment of the eye were fixed with cold acetone and treated with primary antibodies against desmoplakin 1, desmoglein and plakoglobin. Immunolocalization of these substances was visualized by the peroxidase-diaminobenzidine reaction.

RESULTS

A marked immunoreactivity for these desmosome components was detected at the intercellular junction in the normal corneal and conjunctival epithelium. At 6-24 h after epithelial ablation, a weak immunoreactivity for desmoplakin 1 and plakoglobin was observed in the migrating epithelium. At 48 h after epithelial ablation, a marked immunoreactivity for these desmosome components was seen again. At 6-48 h after epithelial ablation, a weak immunoreactivity for desmoglein was observed in the migrating epithelium. At 1 week after epithelial ablation, a marked immunoreactivity for this desmosome component reappeared. The regenerated epithelium gradually exhibited normal immunolocalization of the proteins.

CONCLUSIONS

The desmosome components were considered to be degraded or destroyed prior to epithelial migration and reconstructed during healing of the squamous epithelium.

Matrix metalloproteinases and tissue inhibitors of metalloproteinases of fibrous humans lens capsules with intraocular lenses

PURPOSE

We located immunohistochemically the matrix metalloproteinases (MMP) -1, -2, -3 and -9 and the tissue inhibitors of matrix metalloproteinases (TIMP) -1 and -2 in the fibrous capsule of patients with intraocular lenses (IOLs).

METHODS

During vitreoretinal surgery in 10 patients we obtained post-cataract surgery lens capsules with or without an IOL. The mean interval between the previous cataract operation and the extraction of the specimens was 35.2 months (range: 2-120 months). Circular sections of the anterior capsule with lens epithelial cells (LECs) were also obtained during cataract surgery. Specimens were processed for immunohistochemical identification of MMPs and TIMPs by light microscopy.

RESULTS

While all the members of MMPs and TIMPs were not detected in the normal anterior capsules, they were detected in the ECM and/or LECs on the lens capsules extracted within 18 months after IOL implantations in all of the 4 patients, but were not observed in specimens obtained 18 months or longer postoperatively. In LECs of 1 capsule specimen 10 years postoperatively, MMP-1, but not other MMPs and TIMPs, was detected.

CONCLUSIONS

MMPs and TIMPs were detected in the ECM and/or LECs on post-cataract surgery capsules. These proteins may be remodeling the newly deposited ECM and regulating LEC behavior on residual lens capsules in the early phase of healing after cataract surgery.

Immunohistochemical localization of MYOC/TIGR protein in the trabecular tissue of normal and glaucomatous eyes

PURPOSE

To examine immunohistochemically the localization of myocilin/trabecular meshwork inducible glucocorticoid response (MYOC/TIGR) protein in the glaucomatous and normal trabecular meshworks.

METHODS

Trabecular tissues were used from one eye with late-onset goniodysgenetic glaucoma, three with primary open angle glaucoma (one of which had the MYOC/TIGR gene mutation), two with exfoliation glaucoma and one without glaucoma. For light microscopic immunohistochemistry, frozen sections were stained by the avidin-biotin complex method using anti-MYOC/TIGR polyclonal antibody. For electron microscopic immunohistochemistry, the pre-embedding method using the same antibody was performed. Double immunostaining using both anti-MYOC/TIGR and anti-type VI collagen antibodies was done by the immunofluorescence method.

RESULTS

With light microscopy, immunoreactivity was seen in the whole trabecular meshwork of each of the specimens. No notable differences were detected in staining among the types of glaucoma, or between the eyes with and those without the gene mutation. Under electron microscopy, immunoreaction products were observed not only in the cytoplasm of the trabecular cells but also in the extracellular matrix, where staining was associated with the long-spacing collagen, fine granular materials and possibly microfibrils. With double immunohistochemistry, MYOC/TIGR was colocalized with type VI collagen in the trabecular meshwork.

CONCLUSIONS

In glaucomatous and normal trabecular meshworks, the MYOC/TIGR protein is distributed in the extracellular matrix colocalizing with type VI collagen.

Ribozyme approach to downregulate vascular endothelial growth factor (VEGF) 189 expression in non-small cell lung cancer (NSCLC)

The aim of this study was to further clarify the role of the cell-associated isoform of vascular endothelial growth factor (VEGF189) on tumour growth and vascularity. Five isoforms of VEGF have been identified with different biological activities. VEGF121, VEGF145, VEGF165, VEGF189, VEGF206 are generated by alternative splicing. We used a hammerhead-type ribozyme (V189Rz) to suppress VEGF189 mRNA. The V189Rz specifically cleaved exon 6 of VEGF189 mRNA, but showed no activity against the VEGF121 or VEGF165 isoforms. The V189Rz was introduced into the human non-small cell lung cancer (NSCLC) cell line (OZ-6/VR). The expression level of VEGF189 mRNA was decreased in the OZ-6/VR cells, while VEGF121 and 165 expression was unaltered. The OZ-6/VR cells xenotransplanted into nude mice showed markedly reduced vascularisation and growth, whereas the cell line did not show any decreased growth under tissue culture conditions. The OZ-6/VR cells (1 x 10(5) cells/mouse) formed no tumours, whereas the parental OZ-6 cells formed large tumours within 8 weeks. The specific suppression of VEGF189 by the ribozyme decreased vascularity and xenotransplantability of the lung cancer cell line. Thus, the cell-associated isoform of VEGF, VEGF189, might have a key role in stromal vascularisation and the growth of NSCLC xenografts in vivo.

Expression of involucrin by ocular surface epithelia of patients with benign and malignant disorders

PURPOSE

Keratinization of the ocular surface epithelium is associated with various disorders impairing vision. We immunohistochemically determined whether the ocular surface epithelia express involucrin, and whether its expression pattern may differ in benign vs. malignant disorders. Expression of cytokeratins was also examined to provide further information relative to the epithelial differentiation.

METHODS

We evaluated 17 specimens; 6 specimens of the normal ocular surface epithelia, 3 specimens from cases of conjunctival intraepithelial neoplasia (CIN), 6 of conjunctival squamous cell carcinoma (SCC) and 2 of conjunctivae from cases of superior limbic keratoconjunctivitis (SLK).

RESULTS

Corneal epithelium exhibited intracellular immunoreactivity for involucrin. Four of the 6 specimens of bulbar conjunctival epithelium showed involucrin immunoreactivity in the perimembranous region, whereas the fornical conjunctiva was negative. Cornified envelope in SLK specimens was positive for involucrin. The CIN showed its immunoreactivity in the perimembranous region in all levels of the hyperproliferative epithelium without keratinization, i.e., similar to the bulbar conjunctiva. The neoplastic cells of well-differentiated SCC showed involucrin in the perimembranous region, and those of moderately- to poorly-differentiated SCC have involucrin in their cytoplasm. The expression pattern of cytokeratins was unrelated to grade of malignancy in ocular SCC.

CONCLUSION

The epithelia of normal subjects and of CIN expresses involucrin without keratinization. In contrary, the keratinized SLK epithelium markedly expresses involucrin in the cornified envelope. The subcellular immunolocalization of involucrin in the ocular SCC may help in evaluating the differentiation, i.e., malignancy, of neoplastic cells.