Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls in human milk in Osaka City, Japan

Forty-eight human milk samples were collected from primiparous mothers in Osaka City from June 1999 to January 2000 and analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like coplanar polychlorinated biphenyls (CoPCBs). Mean toxic equivalents (TEQs) in the milk were 13.86 pg I-TEQ/g fat or 16.50 pg World Health Organization (WHO)-TEQ/g fat for PCDDs and PCDFs; 9.87 pg WHO-TEQ/g fat for CoPCBs; and 23.74 pg TEQ/g fat using I-TEQ values of PCDDs and PCDFs or 26.36 pg TEQ/g fat using WHO-TEQ values of PCDDs and PCDFs for total PCDDs, PCDFs, and CoPCBs. The TEQ levels of these chemicals in human milk in Osaka City were in the range of levels in human milk surveyed in Japan, but the TEQ levels of PCDDs and PCDFs and total PCDDs, PCDFs, and CoPCBs from our study were slightly higher than average TEQ levels in human milk in Japan. When comparing our data with the latest data from the United States and some European countries, the TEQ levels of PCDDs and PCDFs in human milk from Osaka City were relatively high, whereas those of CoPCBs were ranked as being of intermediate level. Only TEQ values of CoPCBs in human milk were found to correlate with the increasing age of mothers and their estimated intake of seafood during the year before pregnancy. Concentrations of PCBs 105 and 118 contributed to TEQ values of CoPCBs associated with seafood intake, whereas those of PCBs 156, 157, 114, 189, 167, and 169 contributed to TEQ values of CoPCBs associated with increasing maternal age.

Pyridalyl, a novel insecticide: potency and insecticidal selectivity

Pyridalyl is an insecticide of a novel chemical class (unclassified insecticides). Toxicity of pyridalyl to two insect pest species, Spodoptera litura and Frankliniella occidentalis, an insect predator, Orius stringicollis, and a pollinator, Bombus terrestris, was evaluated in the laboratory. The insecticidal activity of pyridalyl against S. litura was evaluated using the leaf-dipping method. The potency of pyridalyl was highly effective against all development stages (2nd to 6th instar larvae) of S. litura. This compound was also evaluated against F. occidentalis using the direct spray method. For F. occidentalis, toxicity of pyridalyl was almost similar to that of acrinathrin, but greater than acrinathrin for adults. Then the toxicity of this product to the natural enemies, Orius stringicollis and the pollinating insect Bombus terrestris, was evaluated using the body-dipping method or direct spray method. No acute toxicity of this product was observed on these non-target insects. Moreover, the influence of pyridalyl to the nest of Bombus terrestris was evaluated using the direct spray to the inside of the nest. No apparent influence of this compound was observed by 21 days after treatment. The cytotoxicity of pyridalyl to the Sf9 insect cell line and the CHO-K1 mammalian cell line was evaluated using the trypan-blue exclusion method. High toxicity to the insect cell line, but almost no toxicity to the mammalian cell line, was observed. Thus, pyridalyl exhibited high selectivity in cytotoxicity between the insect and mammalian cell line as well as in insecticidal activity among insect species. We infer pyridalyl may be useful for IPM programs of greenhouse cultivation system.

Leukocytapheresis treatment for pyoderma gangrenosum

A 42-year-old man presented with painful erythema with pustules and multiple small ulcers on the shins. He had suffered from ulcerative colitis (UC) and received oral glucocorticosteroid and salicylazosulfapyridine therapies for 7 years. Biopsy of the lesion demonstrated mixed cellular infiltrates with dominant neutrophils. The patient was diagnosed with pyoderma gangrenosum (PG) and underwent leukocytapheresis (LCAP), an extracorporeal leucocyte removal therapy, once a week for 5 weeks without changing the doses of the oral medications. The skin lesions as well as clinical signs of UC rapidly improved after LCAP, and no recurrence was seen during a follow-up period. There were no major complications during LCAP. LCAP will provide an effective and safe tool for the treatment of PG.

HSP47 is a useful marker for skin fibroblasts in formalin-fixed, paraffin-embedded tissue specimens

AIM

This study was undertaken to assess whether heat-shock protein (HSP)47 is a useful cell marker for skin fibroblasts in formalin-fixed, paraffin-embedded skin specimens.

BACKGROUND

HSP47, a 47-kDa HSP, is a collagen-specific molecular chaperone localized in the endoplasmic reticulum. HSP47 plays an essential role in collagen biosynthesis in skin fibroblasts.

METHODS

Immunohistochemistry was performed to detect HSP47 in skin fibroblast cultures and skin tissue sections.

RESULTS

Immunostaining for HSP47 clearly detected skin fibroblasts in paraffin tissue sections as well as in fibroblast cultures and frozen tissue sections. HSP47 staining on paraffin sections from diseased skin specimens revealed that skin ulcer, keloid, nodular fascitis, spindle cell lipoma, and dermatofibroma had strong signals for HSP47 compared with the signals obtained from normal skin. Dermatofibrosarcoma protuberans had many HSP47 positive cells, but signals on individual cells were not as strong as those seen from the above benign proliferative disease samples. In neurofibroma, a small number of faintly positive cells were detected. Our double-immunostaining studies also demonstrated that HSP47 staining distinguished skin fibroblasts from CD68-positive histiocytes/macrophages, factor VIII-related antigen-positive endothelial cells, or factor XIIIa-positive dermal dendritic cells. CD34-positive interstitial cells coexpressed HSP47 in spindle cell lipoma.

CONCLUSIONS

These findings indicate that HSP47 staining can detect skin fibroblasts in routine, paraffin-embedded specimens. A panel approach using HSP47 and other cell markers on paraffin sections may help the identification of the cell type involved with mesenchymal proliferative disorders.

Xanthoma disseminatum with large plaques confined to the back, pulmonary involvement and multiple intestinal xanthomas

Xanthoma disseminatum (XD) is a rare benign mucocutaneous xanthomatosis that is classified as a benign non-Langerhans cell histiocytosis. We report a 68-year-old man who presented with peculiar, large plaques confined to the back 7 years after the onset of cranial diabetes insipidus. Histopathological features of the cutaneous lesions were typical of XD. The patient had lower respiratory tract involvement with histiocytic infiltrates, which was unresponsive to various treatments and resulted in a fatal outcome. Gastrointestinal endoscopies revealed multiple xanthomas in the sigmoid colon and the rectum. To our knowledge, this is the first reported case of intestinal xanthomas associated with XD.

Cell kinetic balance in gastric mucosa with intestinal metaplasia after Helicobacter pylori eradication: 2-year follow-up study

BACKGROUND

Proliferation and apoptosis events are altered in Helicobacter pylori infection. However, whether H. pylori eradication has an effect on the disturbed kinetics in metaplastic mucosa has not been well elucidated.

AIM

To investigate the effect of eradication on the gastric cell kinetics.

SUBJECTS AND METHODS

Initially, biopsies were obtained from 74 H. pylori-infected subjects and repeated 12 and 24 months after eradication. Biopsies were immunohistochemically stained for apoptosis by single-stranded DNA, for proliferation by Ki-67 antibodies and for intestinal metaplasia MUC2, MUC5AC, MUC6 and CD10.

RESULTS

While antral apoptosis in intestinal metaplasia was significantly lower than in non-intestinal metaplasia, proliferation was significantly higher (greater and lesser curvatures, P < 0.05, respectively). This resulted in a significantly lower apoptosis/proliferation ratio in intestinal metaplasia than in non-intestinal metaplasia (antrum greater and lesser curvatures and corpus greater curvature, P < 0.05). After successful eradication, apoptosis and proliferation decreased in both intestinal metaplasia and non-intestinal metaplasia. The pattern of reduction of apoptosis and proliferation differed in these two groups. However, in the corpus, the reduction resulted in a significant increase in the apoptosis/proliferation ratio in both.

CONCLUSION

Proliferation and apoptosis are unevenly and disproportionately altered in H. pylori infection leading to an imbalance in cell kinetics. Eradication of the organism improves the balance and may possibly play a role in the prevention of malignancy transformation in the metaplastic mucosa.

First Report of Stem Rot of Guiana Chestnut (Pachira aquatica) Caused by Pythium splendens

Guiana chestnut is a perennial tropical plant that has recently become popular as a potted ornamental in Japan. In October 2001, severe stem rot occurred on Guiana chestnut plants grown in a greenhouse in Mie Prefecture, Japan. Water-soaked lesions appeared initially at the base of the stems and enlarged gradually toward the tops of plants. The affected tissues were softened and turned dark brown. Rotting was observed in the vascular bundles with advanced disease development. Globose hyphal swellings were numerous on diseased stems. Sections from diseased stems were cleaned by washing with running tap-water, placed on water agar, and incubated at 25°C. A species of Pythium was identified on the basis of morphological and cultural characteristics (1) and isolated consistently from the rotted stems of diseased plants. All isolates produced abundant hyphal swellings that were globose, smooth, 12 to 39 μm in diameter, mostly terminal, dark colored, and with dense granulated contents. Zoospores were absent. All isolates were of the compatibility '+ type' with production of sexual organs when paired with cultures of the '- type' tester isolate of Pythium splendens Braun (CBS462.48). Oogonia produced by crossings between Guiana chestnut isolates and isolate CBS462.48 were terminal or intercalary, globose, smooth-walled, and 32 to 38 μm in diameter. Antheridia were terminal, one to three per oogonium, sac-like, and diclinous. Oospores were single, aplerotic, globose, and 28 to 32 μm in diameter. The thickness of the oospore wall ranged from 1 to 2 μm. The internal transcribed spacer rDNA sequences of representative isolate OPU591 from Guiana chestnut matched those of CBS462.48 (similarity 99.2%) and have been deposited in GenBank under the Accession No. AY375242. Pathogenicity tests were conducted on potted Guiana chestnut plants (30 cm high and 7 to 10 cm in diameter at base of the stem) using isolate OPU591. A mycelial suspension from one culture, grown at 25°C for 7 days on water agar, was inoculated onto a single plant. Prior to inoculation, a wound (10 mm deep and 30 mm long) was made on the surface at the stem base on five plants. The mycelial suspension was poured onto the base of the stems of five wounded and five nonwounded plants. In addition, five wounded and five nonwounded, noninoculated plants were used as controls. Plants were maintained in a greenhouse for 8 weeks after inoculation. The temperature and relative humidity in the greenhouse ranged from 25 to 30°C and 65 to 75%, respectively. Dark-brown rotting developed on the stems of all wounded, inoculated plants by 20 days after inoculation. P. splendens was isolated from diseased tissues and found to be morphologically identical to the original isolate. This confirmed P. splendens as the causal agent of the disease. Disease did not develop on nonwounded inoculated plants or noninoculated plants. To our knowledge, this is the first report of P. splendens on Guiana chestnut. Potted plants of Guiana chestnut are often injured by frequent transplanting and transferring. Such injuries may have predisposed the plant to infection by P. splendens. Reference: (1) A. J. van der Plaats-Niterink. Page 1 in: Monograph of the Genus Pythium. Studies in Mycology Vol. 21, Centraalbureau Voor Schimmelcultures, Baarn, the Netherlands, 1981.

Bioadsorption of cadmium ion by cell surface-engineered yeasts displaying metallothionein and hexa-His

The Cd(2+)-chelating abilities of yeast metallothionein (YMT) and hexa-His displayed on the yeast-cell surface were compared. Display of YMT and hexa-His by alpha-agglutinin-based cell-surface engineering was confirmed by immunofluorescent labeling. Surface-engineered yeast cells with YMT and hexa-His fused in tandem showed superior cell-surface adsorption and recovery of Cd2+ under EDTA treatment on the cell surface than hexa-His-displaying cells. YMT was demonstrated to be more effective than hexa-His for the adsorption of Cd2+. Yeast cells displaying YMT and/or hexa-His exhibited a higher potential for the adsorption of Cd2+ than Escherichia coli cells displaying these molecules. In order to investigate the effect of the displayed YMT and hexa-His on sensitivity to toxic Cd2+, growth in Cd(2+)-containing liquid medium was monitored. Unlike hexa-His-displaying cells, cells displaying YMT and hexa-His fused in tandem induced resistance to Cd2+ through active and enhanced adsorption of toxic Cd2+. These results indicate that YMT-displaying yeast cells are a unique bioadsorbent with a functional chelating ability superior to that of E. coli.

Effects of cysteine on the cytotoxicity of arsenic compounds

Effects of cysteine on the cytotoxicity of arsenic compounds, such as arsenite, arsenate, methylarsonic acid (MMA), and dimethylarsinic acid (DMA), were investigated in cultured human HL-60 cells. Using adenosine triphosphate bioluminescence assay, the rank order of the mixtures of arsenicals with cysteine was: DMA > arsenite > arsenate > MMA. The IC50 of DMA with equimolar cysteine was approximately 7.7 microM, nearly two orders of magnitude lower than that of DMA alone. Apoptotic cells were examined by the TUNEL method, and cysteine was found to enhance the induction of apoptosis by arsenicals. Using LC-ICP-MS, trivalent arsenic was detected in the mixtures of arsenate, DMA, and MMA with cysteine. These results suggested that the trivalent arsenic in the mixtures of arsenicals with cysteine might account for the enhanced cytotoxicity as well as apoptosis, and that cysteine is involved in induction of the adverse effects of arsenicals in humans.

Levofloxacin based triple therapy as a second-line treatment after failure of helicobacter pylori eradication with standard triple therapy

BACKGROUND

Successful eradication of Helicobacter pylori infection after failure of standard triple therapy is difficult. The efficacy and safety of levofloxacin based triple therapy as a first-line therapy has-been studied.

AIMS

The aim was to evaluate the efficacy and tolerability of levofloxacin based therapy after a failed standard triple therapy.

PATIENTS

We conducted a prospective, uncontrolled study of a consecutive series of 33 patients who failed eradication with 1 week of lansoprazole-amoxicillin-clarithromycin triple therapy.

METHODS

The subjects were retreated with 1 week of LA-LVFX triple therapy (lansoprazole, 30 mg twice daily; amoxicillin, 1000 mg twice daily: levofloxacin, 200 mg twice daily). Cure of infection was defined as negative results from culture, histology and a urea breath test 4 to 8 weeks after the second-line therapy.

RESULTS

The eradication rate was 69.7% (23/33) by both intention-to-treat and per-protocol analyses (95% confidence interval=61-79%). Seven (21.2%) patients experienced mild side-effects, such as soft stools and taste disturbance. No patient stopped the medication on account of adverse effects.

CONCLUSIONS

Levofloxacin based triple therapy is an effective second-line treatment after a failed standard triple therapy.

Flow-mediated dilation in brachial artery in the second half of pregnancy and prediction of pre-eclampsia

Endothelial injury and increased vascular reactivity are involved in the pathogenesis of pre-eclampsia (pregnancy-induced hypertension). To investigate whether flow-mediated dilation (endothelium-dependent dilation) and the reactive hyperemic response can predict pre-eclampsia, we prospectively measured flow-mediated dilation and the Doppler flow velocity pattern (V, cm/s) in the brachial artery using high-resolution ultrasound in 43 pregnant women (32+/-5 years old) in the second half of their pregnancy, and compared the findings with traditional risk factors. Regarding the Doppler flow velocity pattern, the pulsatility index (PI)=(systolic V-diastolic V)/mean V and resistance index (RI)=(systolic V-diastolic V)/systolic V were calculated. For the flow-mediated dilation, the per cent diameter changes were determined based on those from baseline to hyperemic conditions. Nine women suffered from pre-eclampsia and 34 women remained normotensive. Only flow-mediated dilation was found to be significantly lower in the subsequently developed pre-eclampsia patients (1.6+/-1.0% in subsequently developed pre-eclampsia patients vs 11.0+/-4.5% in normotensive patients, P<0.05). Neither the other traditional factors nor the Doppler flow velocity pattern were significantly different between the subsequently developed pre-eclampsia and normotensive patients. If a normal cutoff value of 3.0% obtained from age-matched 14 nonpregnant women (32+/-7 years old) in our laboratory was used, the positive predictive value of flow-mediated dilation (<3.0%) for subsequent pre-eclampsia is 90% and the negative predictive value is 100%. In conclusion, flow-mediated dilation in brachial artery can be a simple and noninvasive modality to predict pre-eclampsia.

Clinical study of urine NMP 22 (nuclear matrix protein 22) as a tumor marker in urinary epithelial cancer

The prognosis of urinary epithelial cancer is still poor, and early detection of this cancer is strongly desirable. The sensitivity of conventional urinary cytology is not satisfactory enough. It is hoped that a specific tumor marker will be established. In recent years, it has been reported that urine NMP 22 is very useful and that urine BFP is also relatively useful. We have now determined urine NMP22 and BFP and studied their clinical usefulness as a tumor marker. Using patients diagnosed with histologically confirmed urinary epithelial cancer as the subjects, we retrospectively studied the usefulness of NMP 22, BFP and cytology mainly with regard to the sensitivity (positivity rate), and also in relation to atypia, degree of infiltration and clinical course.

Increased procollagen alpha1(I) mRNA expression by dermal fibroblasts in melorheostosis

We report a patient with melorheostosis in whom increased procollagen alpha1(I) mRNA expression and alpha1(I), alpha2(I) and alpha1(III) collagen secretion were observed in dermal fibroblasts obtained from a skin biopsy overlying the involved bone. The patient was a 53-year-old man with melorheostosis lesions over the left knee joint. Multiple pigmented macules were present on the medial aspect of the lower left leg. Hyperpigmentation of the basal keratinocytes, thick-walled vessels in the reticular dermis, and proliferation of normal-appearing collagen around the hair follicles were observed histologically.

Acute haemorrhagic oedema of infancy associated with cytomegalovirus infection

Acute haemorrhagic oedema (AHO) of infancy is a cutaneous leukocytoclastic vasculitis, clinically characterized by the acute development of peripheral oedema and targetoid purpuric lesions on the face and extremities. It usually affects children younger than 2 years of age. The disorder follows a benign course usually without recurrence or long-term complication. In most cases the origin is not clear, but underlying infections are assumed to play an aetiological role. We describe a 7-month-old boy whose clinical and histopathological features are typical of AHO. Serological tests clearly demonstrated a primary infection for cytomegalovirus (CMV). To our knowledge, this is the first reported case of AHO associated with CMV infection.

Genotoxicity of gardenia yellow and its components

Gardenia fruit (Gardenia jasminoides ELLIS) is widely used as a natural food colorant and as a traditional Chinese medicine for treatment of hepatic and inflammatory diseases. "Gardenia yellow" is a natural food colorant which is extracted by ethanol from gardenia fruit. The purpose of this study was to evaluate the genotoxicity of gardenia yellow. Genotoxicity of gardenia yellow and its components, crocetin, gentiobiose (a component of crocin), geniposide and genipin (formed by hydrolysis of geniposide), was studied by Ames test, rec-assay, and sister chromatid exchange (SCE) using V79 cells. Gardenia yellow and its components were found not to be mutagenic in the Salmonella reverse mutation assay. Gardenia yellow and genipin caused damage of DNA in rec-assay. Gardenia yellow induced a significant dose-dependent increase of SCE frequency (8.6 times at 1000 microg/ml as the value for the solvent control). Only genipin induced SCEs significantly among the components of gardenia yellow. Moreover, genipin induced a significant increase of tetraploids at all doses tested (95% at 8 microg/ml). Gardenia yellow preparation was analyzed by capillary electrophoresis (CE), and geniposide was detected. However, genipin was not observed. In conclusion, we have shown that genipin possesses genotoxicity. Furthermore, there were unidentified genotoxicants in gardenia yellow.

Variation in MT expression in early-stage depressed-type and polypoid-type colorectal tumours

Metallothionein (MT) expression is observed in various carcinomas, but its role is not fully understood. To clarify the clinicopathological significance of MT, 87 colorectal adenomas and 128 early-stage carcinomas were immunohistochemically analysed for MT expression. The degree of MT immunostaining of a specimen was graded according to the proportion of MT-positive cells; negative (<5%) and positive (focally 5-50%, diffusely >50%). MT expression significantly decreased with tumour development. For carcinomas, MT-positivity was significantly associated with depth of invasion (T1 60% versus T2 33%; P<0.01), vascular involvement (positive 35% versus negative 61%; P<0.01) and morphology (polypoid 62% versus depressed 26%; P<0.01). Regarding MT-positive distribution, the diffuse-positive rate in MT-positive polypoid lesions was 28%, while MT-positive depressed lesions were all diffusely stained (P<0.01). In conclusion, our results suggested that decreasing MT expression is an early event in colorectal carcinogenesis and may reflect local invasion. Furthermore, MT-positive distribution may reflect genetic differences between the polypoid and depressed-type.

Clinical study on the antiseptic effect of povidone-iodine solution for the surgical field of digestive tract operations

Our previous study showed 10% povidone-iodine solution (Isodine) to be safe and effective for skin antisepsis in healthy young adults. The present study was carried out in 45 adult and old-age patients undergoing surgery (average age 62 years). 10% povidone-iodine solution was effective for skin antisepsis; however, after completion of the intra-abdominal procedures, contaminations were found due to the type II and IV operations with unprotected incision sites and wound walls. Diabetes was found to be one of the most important factors in surgical site infection. In conclusion, the antiseptic efficacy immediately after application of 10% povidone-iodine solution was evidenced in surgical patients with class II wounds. The solution was also effective for the prevention of postoperative skin wound infection.

Cell surface-engineered yeast with ability to bind, and self-aggregate in response to, copper ion

In order to construct a cell surface-engineered yeast Saccharomyces cerevisiae that facilitates adsorption and recovery of heavy metal ions, we endowed it with the ability to self-aggregate in response to binding and accumulation of copper ion. A fusion gene for the expression of GTS1, which encodes a putative zinc-finger transcription factor related to occurrence of cell-aggregation, was constructed under the control of the copper ion-inducible CUP1 promoter from the yeast metallothionein gene. The multicopy plasmid carrying the fusion gene was introduced into a cell surface-engineered yeast displaying histidine hexa-peptide, which can chelate copper ion. This transformant strain aggregated in medium only in the presence of copper ion, with aggregation induced by as little as 1 mM copper ion. The copper ion-induced aggregation did not interfere with the copper ion-adsorbing function of the cell surface-engineered yeast, indicating that this transformant strain has the twin features of enhanced cell surface adsorption of copper ion and self-aggregation in response to environmental copper ion.

An arming yeast with the ability to entrap fluorescent 17beta-estradiol on the cell surface

We constructed a novel surface-engineered yeast displaying the ligand-binding domain of the rat estrogen receptor (ERLBD). ERLBD, display of which on the yeast cell surface was confirmed by immunofluorescence, possessed strong binding activity to fluorescent 17beta-estradiol - an analogue of the natural ligand of the estrogen receptor - that was comparable to the activity of the native receptor. Environmental homeostasis has recently been disturbed by endocrine disruptors, which cause confusion in the hormone secretion system. It is therefore very important to identify chemical compounds with hormone-like activity and remove them from the environment. The present results demonstrate that the new arming yeast displaying ERLBD on its cell surface will be capable of screening, entrapping, and removing estradiol-like compounds from the environment.