Modifying effects of 1'-acetoxychavicol acetate (ACA) and the novel synthetic retinoids Re-80, Am-580 and Am-55P in a two-stage carcinogenesis model in female rats

Effects of dietary administration of 1'-acetoxychavicol acetate (ACA) and the novel synthetic retinoids 4-[1-hydroxy-3-oxo-3-(5,6,7,8-tetrahydro-3-hydroxy-5,5,8,8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid (Re-80); 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carboxamido]benzoic acid (Am-580); and 6-[(3,5-di-tert-butylphenyl) carbamoyl]nicotinic acid (Am-55P) were examined using a two-stage rat carcinogenesis model. A total of 190 female SD rats was treated sequentially with 1,2-dimethylhydrazine (DMH, s.c.); 7,12-dimethylbenz(a)anthracene (DMBA, i.g.); and 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN, in the drinking water) during the first three weeks (DDD-initiation), and an additional 60 rats received the vehicle alone (non-initiation). One week after the completion of the initiation period, they were divided into nine groups and administrated Re-80 (at dose levels of 1.0 or 0.4 ppm), Am-580 (20 or 4 ppm), Am-55P (20 ppm), ACA (100 ppm), all-trans-retinoic acid (10 or 2 ppm) or no supplement in the diet for 33 weeks, until survivors were euthanatized at week 37 weeks. After DDD-initiation, all-trans-retinoic acid at the high dose delayed the development of mammary tumors. The multiplicity of colon tumors in the group fed Am-55P and the incidences of nephroblastomas with ACA or Am-580 were decreased as compared with the control values, but the other chemicals had no modifying effects on tumor development in any organs. Thus, among ACA and the novel synthetic retinoids tested, only Am-55P showed a weak inhibitory effect on a neoplasm of general interest under the present experimental conditions.     

Cytopathic astrovirus isolated from porcine acute gastroenteritis in an established cell line derived from porcine embryonic kidney.

A cytopathic astrovirus was isolated from pigs with acute diarrhea in an established cell line that was derived from porcine embryonic kidneys with the aid of trypsin. The virus showed a distinct cytopathic effect characterized by an enlargement of cells and the appearance of fine granules in the cytoplasm. Porcine astrovirus was shown to have an RNA genome, as determined by the effect of 5-iodo-2'-deoxyuridine on its replication, and five polypeptides with molecular masses of 13,000, 30,000, 31,000, 36,000, and 39,000 daltons; and it was shown to be stable to lipid solvents and heating at 50 degrees C for 30 min but somewhat labile to acid (pH 3.0). The buoyant density of the isolate determined in CsCl was 1.35 g/ml. Seroconversion to the virus was evident in the paired serum specimens obtained from pigs with diarrhea that were housed at the farm where the disease occurred. The neutralization test on serum specimens collected randomly from 128 adult pigs of eight herds revealed that 50 of the serum specimens were positive for antibody to porcine astrovirus, although there was considerable variation in the prevalence among herds, ranging from 0 to 83%. Hysterectomy-produced, colostrum-deprived, 4-day-old pigs developed mild diarrhea after oral exposure to porcine astrovirus propagated in the cell culture; and the virus was isolated again from diarrheal stool specimens.     

Granuloma associated with Trichosporon asahii infection in the lung: Unusual pathological findings and PCR detection of Trichosporon DNA.

We describe the first case of a Trichosporon asahii infection of the lung characterized by an epithelioid granuloma with multinucleated giant cells. The patient died of respiratory failure due to lung fibrosis and lung cancer. Autopsy showed primary lung cancer with metastasis, lung fibrosis, and a focal infectious lesion containing the filamentous and yeast forms of a fungus. From its shape the fungus was judged to be Trichosporon, but unusual pathological findings revealed an epithelioid granuloma with multinucleated giant cells surrounding the hyphae and yeast cells. Immunohistochemical staining was performed using the specific Trichosporon spp. monoclonal antibodies and DNA identificationn was done by the PCR. The results showed this case to be a localized Trichosporon asahii infection. Hypersensitivity pneumonitis (HP) due to Trichosporon spp. with its pathological finding of inflammation with granuloma is common, but infections with granulomatous inflammation are extremely rare. This case suggests that Trichosporon infection may develop into granuloma with multinucleated giant cells.     

Prevention of polyglutamine oligomerization and neurodegeneration by the peptide inhibitor QBP1 in Drosophila

Polyglutamine (polyQ) diseases are a growing class of inherited neurodegenerative diseases including Huntington's disease, which are caused by abnormal expansions of the polyQ stretch in each unrelated disease protein. The expanded polyQ stretch is thought to confer toxic properties on the disease proteins through alteration of their conformation leading to pathogenic protein-protein interactions including oligomerization and/or aggregation. Hypothesizing that molecules with selective binding affinity to the expanded polyQ stretch may interfere with the pathogenic properties, we previously identified Polyglutamine Binding Peptide 1 (QBP1) from combinatorial peptide phage display libraries. We show here that a tandem repeat of the inhibitor peptide QBP1, (QBP1)(2), significantly suppresses polyQ aggregation and polyQ-induced neurodegeneration in the compound eye of Drosophila polyQ disease models, which express the expanded polyQ protein under the eye specific promoter. Most importantly, (QBP1)(2) expression dramatically rescues premature death of flies expressing the expanded polyQ protein in the nervous system, resulting in the dramatic increase of the median life span from 5.5 to 52 days. These results suggest that QBP1 can prevent polyQ-induced neurodegeneration in vivo. We propose that QBP1 prevents polyQ oligomerization and/or aggregation either by altering the toxic conformation of the expanded polyQ stretch, or by simply competing with the expanded polyQ stretches for binding to other expanded polyQ proteins. The peptide inhibitor QBP1 is a promising candidate with great potential as a therapeutic molecule against the currently untreatable polyQ diseases.     

Evaluation of the simultaneous detection system for Chlamydia trachomatis/Neisseria gonorrhoeae DNA by the isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN)

The isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN) is a new isothermal DNA amplification method composed of exo Bca DNA polymerase, RNaseH and DNA-RNA chimeric primers. We developed the simultaneous detection system for Chlamydia trachomatis/Neisseria gonorrhoeae DNA, combined with luminescence detection by a probe hybridization. In the performance tests, this system was able to detect 10 to 100 copies of C. trachomatis/N. gonorrhoeae DNA for only 3.5 hours, and was highly specific to C. trachomatis/N. gonorrhoeae without any cross-reaction to C. pneumoniae, N. lactamica, N. sicca or N. meningitidis. When we tested 60 clinical samples of urine and cervical swabs, the interpretive results were completely consistent with those obtained by Roche PCR system. Of 13 positive samples by the ICAN and PCR systems for C. trachomatis, four were negative by EIA method(IDEIA Chlamydia). These results indicate that the ICAN system is an efficient and sensitive system to simultaneously detect C. trachomatis/N. gonorrhoeae DNA.     

Lack of synergism among DMAB, BOP, and MNU in induction of carcinomas of the rat ventral prostate.

The present experiment was undertaken to investigate possible synergism in induction of rat prostate tumor. F344 rats were repeatedly administered the prostate carcinogens 3,2'-dimethyl-4-aminobiphenyl (DMAB),N-nitrosobis(2-oxopropyl)amine(BOP), and N-methylnitrosourea (MNU) sequentially or together at times of hormonal castration induced regenerative cell proliferation of prostate epithelial cells. Group 1 animals received two 100 mg/kg doses of DMAB, two 20 mg/kg applications of BOP, and two times 15 mg/kg of MNU. Groups 2, 3, and 4, respectively, received each of the carcinogen treatment alone. Group 5 was given 6 applications of all three in combination, each at one-third the dose administered to the other groups. The results showed a clear synergism in enhanced tumor development in the colon but not in the prostate, in which the incidence of lesions induced by the three carcinogens was similar to that with DMAB alone.     

MARKED EPITHELIAL HYPERPLASIA OF THE RAT GLANDULAR STOMACH INDUCED BY LONG-TERM ADMINISTRATION OF IODOACETAMIDE

Iodoacetamide (IAA), an ulcerogenic compound, was continuously given to male Wistar rats for up to 74 weeks. No carcinomas developed but marked glandular hyperplasias were frequently observed accompanied by chronic ulcer or erosion in the fundic region. They showed pseudo-invasive growth into the submucosa, the granulomatous tissue and even into the muscle layer, but no cellular and nuclear atypia was observed in their glands. Characteristically the mucosal damage caused by chronic IAA treatment was restricted to the fundic mucosa along the limiting ridge. Abnormally regenerated mucosa in the damaged area showed pyloric gland type metaplasia, demonstrated histo-chemically by paradoxical concanavalin A-staining and high-iron diamine-Alcian blue staining for mucin. No intestinal metaplasia was observed in these mucosa.     

Pathogenicity of avian nephritis virus in chicks previously infected with infectious bursal disease virus

Pathogenicity of avian nephritis virus (ANV) was studied in 7‐day‐old chicks previously infected with infectious bursal disease virus (IBDV) at 1 day of age. Three IBDV+ANV infected chicks were found dead with no apparent clinical signs within 10 days of inoculation with ANV and they had marked urate deposits throughout the body. All of the surviving IBDV+ANV infected chicks had reduced body weight gain, unlike the ANV‐only infected, IBDV‐only infected and non‐infected control chicks.

In a chronological study, all of the ANV‐infected chicks revealed interstitial nephritis accompanied by tubular cell degeneration and lymphoid cell infiltration. Avian nephritis virus antigen was detected with equal sensitivity by fluorescent antibody and immunoperoxidase techniques and was widely distributed in the degenerated epithelial cells. The concentration of serum uric acid in IBDV+ANV infected chicks was higher than that in ANV‐only infected chicks. The antibody against ANV in ANV‐only infected chicks was first detected 8 dpi and its titre increased gradually. In contrast, the antibody in the IBDV+ANV infected chicks was very low and was detected in only three out of seven chicks 16 dpi; the titre was 1:4 in one chick and 1:8 in the other 2 chicks. Coincident with serological results, the number of lgG‐ and IgM‐containing cells in the kidneys and spleen were less in IBDV + ANV‐infected chicks than in ANV‐only infected chicks. These finding suggested that IBDV infection in chicks might influence the immunological response and susceptibility to subsequent ANV infection.     

Nutritional Assessment in Adult Patients with Dysphagia: A Scoping Review

Malnutrition negatively affects the quality of life of patients with dysphagia. Despite the need for nutritional status assessment in patients with dysphagia, standard, effective nutritional assessments are not yet available, and the identification of optimal nutritional assessment items for patients with dysphagia is inadequate. We conducted a scoping review of the use of nutritional assessment items in adult patients with oropharyngeal and esophageal dysphagia. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched to identify articles published in English within the last 30 years. Twenty-two studies met the inclusion criteria. Seven nutritional assessment categories were identified: body mass index (BMI), nutritional screening tool, anthropometric measurements, body composition, dietary assessment, blood biomarkers, and other. BMI and albumin were more commonly assessed in adults. The Global Leadership Initiative on Malnutrition (GLIM), defining new diagnostic criteria for malnutrition, includes the categories of BMI, nutritional screening tool, anthropometric measurements, body composition, and dietary assessment as its required components, but not the blood biomarkers and the “other” categories. We recommend assessing nutritional status, including GLIM criteria, in adult patients with dysphagia. This would standardize nutritional assessments in patients with dysphagia and allow future global comparisons of the prevalence and outcomes of malnutrition, as well as of appropriate interventions.