The Acute and Chronic Toxicities of Nivalenol in Mice

The Acute and Chronic Toxicities of Nivalenol in Mice. Ryu,J.-C, Ohtsubo, K., Izumiy-ama, N., Nakamura, JL, Tanaka, T.,Yamamura, H., and Ueno, Y. (1988). Fundam. Appl Toxicol. 11,38–47. In an attempt to ascertain precisely the toxiceffects of nivalenol (N1V), we conducted the determination ofLD50 values, and interim kills during the carcinogenic studyin mice. LD50 values (mg/kg) of NIV in 6-week-old male ddY micewere determined as 38.9 (po), 7.4 (ip), 7.2 (sc), and 7.3 (iv).Seven-week-old female C57BL/6CrSlc SPF mice were fed diets containing0, 6, 12, and 30 ppm (mg/kg) NIV over 1 year, and were assessedfor effects on body weight gain, feed efficiency, terminai organweights, hematology, and histopathology. The rates of body weightgain and feed efficiency showed a good dose-dependent correlationin all experimental periods. Gross and histopathological evaluationof the liver, thymus, spleen, kidneys, stomach, adrenal glands,pituitary gland, ovaries, sternum, bone marrow, lymph node,brain, and small intestines with or without Peyer's patch portionfrom control and all NIV-exposed mice revealed that these tissueswere normal in appearance and in histopathological structure.Also, no changes were observed in the ultrastructural studieson the bone marrow. Dietary NIV did, however, cause dose-dependentdecreases of absolute organ weights (mg) and increases of relativeorgan weights (mg/g body weight) in the terminal organ weightsrecorded. A significant leukopenia was observed in the 30 ppmgroup at 6 months and in all NIV-treated groups at 1 year. Nomarked changes were observed in the other hematological parameters.These results indicated that 6 ppm or more of dietary NIV for1 year showed a characteristic toxic effect of trichothecenemycotoxins in mice.     

Testosterone inhibits immunoglobulin production by human peripheral blood mononuclear cells

We studied the in vitro effect of testosterone on spontaneous immunoglobulin production by human peripheral blood mononuclear cells (PBMC). Testosterone inhibited IgG and IgM production by PBMC both from males and females. The inhibitory effect of testosterone was revealed at doses more than 1 nm, increased dose-dependently, and reached a plateau at 100 nm. At doses <1000 nm, testosterone did not reduce cell viability. Testosterone treatment reduced IgG production by 59.0% and that of IgM by 61.3% compared with control. Immunoglobulin production by B cells was also suppressed by testosterone, though the magnitude of the suppressive effect on B cells was lower than that on whole PBMC; testosterone-induced decrease of IgG production compared with control was 26.9% and that of IgM was 24.9%. Exogenous IL-6 partially restored the impaired immunoglobulin production of testosterone-treated PBMC; IgG production in testosterone culture was increased by IL-6 from 35.6% to 66.5% of control and that of IgM was also increased from 38.9% to 71.2%, respectively. Testosterone treatment reduced IL-6 production of monocytes by 78.4% compared with control, but neither affected that of T cells or B cells. These results suggest that testosterone may suppress immunoglobulin production of human PBMC directly by inhibiting B cell activity and indirectly by reducing IL-6 production of monocytes. It is thus indicated that this hormone may have protective and therapeutic effects on human autoimmune diseases.     

Characteristics of juvenile dermatomyositis in Japan

Questionnaires were sent to 1290 hospitals in Japan asking for data on patients with juvenile dermatomyositis (JDM) diagnosed between June 1984 and May 1994. Of the 204 patients identified by these questionnaires, 102 met the criteria for JDM. JDM is categorized into three subtypes: Banker-type JDM , Brunsting-type and fulminant-type; patients with the latter exhibit markedly elevated serum levels of creatinine phosphokinase (> 10 000 U/mL) and appear to be at risk of renal failure. Cutaneous manifestations were present in 98% of patients and preceded the appearance of other symptoms. This tendency is one of the reasons for the difficulty in some cases in diagnosing the onset of JDM. Better criteria for early treatment of JDM are needed. The results of the present study suggest that itching and calcinosis are factors that indicate a poor prognosis in patients with JDM. Muscle enzyme levels do not always reflect disease activity, suggesting that methods other than measurement of muscle enzymes, such as measurement of the levels of neoprerin and von Willebrand factor antigen, as well as magnetic resonance imaging should be used to be evaluate disease severity. Patients with Brunsting-type JDM who exhibit dysphagia and antinuclear antibody positivity and patients with Banker-type JDM should be treated aggressively. Pulse therapy should be selected as the initial therapy in patients with fulminant-type JDM.     

DETECTION OF ANTIRIBOSOMAL P PROTEIN ANTIBODIES IN PATIENTS WITH SYSTEMIC SCLEROSIS

This study investigated the prevalence and clinical significanceof anti-ribosomal P protein (anti-P) antibodies in patientswith systemic sclerosis (SSc). Serum samples from 150 patientswith SSc were examined by indirect immunofluorescence, ELISAand immunoblotting. Anti-P antibodies were detected in four(3%) patients with SSc. Three of the four patients showed SSc/SLE(systemic lupus erythematosus) overlap syndrome, but psychiatricdisorders were not observed in these patients. By longitudinalimmunoblotting analysis one patient, who was initially diagnosedwith SSc, later developed anti-P antibodies along with clinicalmanifestations of SLE. Our data suggest that anti-P antibodiesare uncommon in SSc and that the presence of anti-P antibodiesin patients with SSc indicates an overlap with SLE. KEY WORDS: Anti-ribosomal P protein antibodies, Systemic sclerosis, Systemic lupus erythematosus     

Secondary cutaneous candidiasis with eosinophilia

Cutaneous candidiasis is a common skin infection caused by the Candida species, especially in intertriginous areas, and neutrophils usually infiltrate histopathologically. We describe a case of secondary cutaneous candidiasis which spread extensively to the trunk and extremities and showed marked dermal eosinophilia. This case and a similar reported case suggest that Candida can sometimes cause cutaneous inflammation predominantly composed of eosinophils.     

A case of granular cell tumor of the bladder successfully managed with extraperitoneal laparoscopic surgery

Granular cell tumor is a benign neoplasm which frequently occurs in the oral cavity, skin, and subcutaneous tissue. Granular cell tumor of the bladder is an extremely rare disease, and only nine cases have been reported. We present here an additional case of granular cell tumor occurring in the bladder. Unlike the other tumors reported, this tumor extruded into the Retzius' cavity. Therefore, the tumor was successfully excised through extraperitoneal laparoscopic surgery. The patient was free from recurrence 40 months after surgery. The small tumor located in Retzius' cavity could be managed with extraperitoneal laparoscopic surgery.     

Antigenicity of premelanosomes and melanoma cytotoxic activity demonstrated by spleen mononuclear cells of melanoma-bearing hamster

The antigenicity of premelanosomes, which are specific organelles for melanin biosynthesis in the cytoplasm of malignant melanoma cells, has been revealed by the blastogenic responses of lymphocytes from melanoma-bearing Syrian (golden) hamsters, using the lymphocyte stimula tion assay. The lymphocytes from these hamsters have also been found to exhibit cytotoxic effects on cultured melanoma cells as shown by the microcytotoxic assay technique.