Menstrual cycle dependent expression of CD44 in normal human endometrium

CD44 is a cell surface glycoprotein known to be a hyaluronate receptor, which functions in lymphocyte homing and cancer metastasis. We have previously shown that CD44 molecules are expressed in normal endometrial tissue. In this study we immunohistochemically examined expression of CD44 glycoproteins in normal human endometrial tissue to gain insight into roles of CD44 molecules. No expression of the CD44 standard form was observed with 11 endometria in the proliferative phase. On the contrary, 13 of 19 secretory phase endometria were stained intensely by anti-CD44 standard form anti-body; all CD44-positive cases were in the mid and late secretory phases. Among the 13 CD44-positive endometria, four also were positive for the CD44 variant with exon v6. CD44 molecules were present at all but the luminal cell surfaces. These results indicate that expression of CD44 depends on menstrual cycle, suggesting that CD44 molecules might be involved in implantation of fertilized ovum in endometrium.

[Two-color flow cytometry analysis of lymphocyte subsets in patients with acute myocardial infarction and post-myocardial infarction syndrome]

Serial changes in lymphocyte subsets were analyzed in 37 patients with acute myocardial infarction (AMI), in 2 patients with postmyocardial infarction syndrome (PMIS), and in healthy subjects (control group) using two-color flow cytometry to investigate cellular immunity after AMI and PMIS. Peripheral blood lymphocyte subsets were measured on admission and at weeks 2, 4, 8, and 16 after the onset of AMI. The white blood cell count was significantly higher on admission and at week 2 in the AMI group compared with the control group. The percentage of CD4-positive helper T cells was significantly higher on admission and at weeks 2 and 4 in the AMI group compared with the control group, and the percentage of CD8-positive suppressor T cells was significantly lower in the AMI group at week 2 than in the control group. The ratio of helper-to-suppressor T cells peaked 2 weeks after the AMI and then decreased gradually. There were no significant changes in the CD4/CD8 ratio, the percentage of cytotoxic T cells, or the percentage of inducer T cells, throughout the observation period. There were no significant differences in the percentage of T cells, B cells, CD4-positive T cells, CD8-positive T cells, and natural killer cells between AMI patients and control subjects. The percentage of activated CD4- and CD8-positive cells was higher in the AMI group at weeks 4 and 8 than in the control group. There was no significant correlation between changes in lymphocyte subsets and infarct size. The percentage of activated CD8-positive cells was consistently higher in the PMIS group compared with the control and AMI groups. The percentage of cytotoxic T cells in one of the PMIS patients was significantly higher than in the AMI group. There were no significant differences in the proportions of other subsets between PMIS and AMI patients. The changes in lymphocyte subsets observed in patients with AMI suggested that immunological competence was enhanced in these patients. Abnormalities in humoral immunity, such as the appearance of anticardiac antibody, have been observed in patients with PMIS. Our results suggest that PMIS is also associated with changes in cellular immunity.

Induction of potent humoral and cell-mediated immune responses following direct injection of DNA encoding the HIV type 1 env and rev gene products

DNA vaccines have the potential of giving rise to a potent cell-mediated immune response by inducing intracellular synthesis and subsequent antigenic presentation of encoded antigens. We have tested a DNA vaccine specific for human immunodeficiency virus type 1 (HIV-1) by the injection of animals with expression plasmids encoding the HIV-1 envelope protein and the Rev regulatory protein. Injection of both plasmids into mice, rabbits, or macaques was found to induce high levels of specific antibodies capable of efficiently inhibiting both HIV-1 infection and envelope-mediated cell fusion. A readily detectable delayed-type hypersensitivity (DTH) response was demonstrable in injected mice and lymphocytes derived from these proliferated in response to an HIV-1 envelope V3 loop-specific peptide. Interestingly, the injected mice or macaques also developed a strong cytotoxic T lymphocyte (CTL) response against target cells pulsed with the V3 peptide. Taken together, these data demonstrate that injection of HIV-1 gene expression plasmids can induce potent humoral and cell-mediated immune responses and suggest that DNA vaccines may prove to be significantly beneficial as a means of immunizing against HIV-1.

Monoclonal nonspecific suppressor factor beta inhibits interleukin-4 secretion by a type-2 helper T cell clone

Monoclonal nonspecific suppressor factor (MNSF) is a lymphokine product of a murine T cell hybridoma that inhibits the generation of lipopolysaccharide-induced immunoglobulin secreting cells in an antigen-nonspecific manner. Most recently, a cDNA clone encoding MNSF beta, a subunit of MNSF, was isolated and sequenced (Nakamura et al., Proc. Natl. Acad. Sci. USA 1995. 92: 3463). The MNSF beta cDNA encodes a 14.5-kDa ubiquitin-like protein showing several MNSF activities. We have previously observed that hybridoma-derived native MNSF can inhibit interleukin (IL)-4 secretion by bone marrow-derived mast cells. Therefore, we studied whether MNSF beta is also able to inhibit IL-4 secretion by the type-2 helper T cell clone D10. G4.1. MNSF beta inhibited both the IL-4 secretion and the proliferation of concanavalin A-activated D10 cells, although neither effect was complete.

Reduced muscle uptake of oxygen during exercise in patients with systemic lupus erythematosus

OBJECTIVE

To assess the factors limiting aerobic exercise capacity in patients with systemic lupus erythematosus (SLE).

METHODS

The anaerobic threshold (AT) and O2 pulse, i.e., VO2/heart rate (HR), were measured in 21 patients with SLE without cardiopulmonary complications by the analysis of expired gas during incremental work load in exercise testing. The relationships between work rate (WR) and VO2, HR and VO2/weight (Wt), and lupus activity index (LAI) and AT were analyzed.

RESULTS

The AT of the patients with SLE was significantly lower than for a control group. Little increase in O2 pulse and very low delta VO2/delta WR and delta VO2/Wt@delta HR were found during work load in some patients with SLE, especially those with a low AT and high LAI. Patients with SLE with a high LAI tended to show a low AT.

CONCLUSION

The low aerobic exercise capacity of patients with SLE appeared to be mainly due to a small increase in O2 pulse. This may have resulted from impaired oxygen diffusion in the inflamed peripheral muscles in patients with active SLE. Low AT may explain in part why patients with SLE become easily fatigued.

Application of curdlan to controlled drug delivery. II. In vitro and in vivo drug release studies of theophylline-containing curdlan tablets

Tablets (300 mg) having two different surface areas were prepared from spray-dried particles of curdlan (100 mg)/theophylline(200 mg). Drug release from the tablets was studied in vitro and in vivo. The in vitro drug release from a tablet with a larger surface area (Tab L) was faster than that with a smaller one (Tab S). The water uptake of Tab L was larger than that of Tab S, probably due to the difference in the tablets' surface areas. However, the water uptake was not a rate-determining step for the drug release from curdlan tablets containing a large amount of theophylline. A straight line was obtained when release % was plotted vs. time. The slope of each curve was calculated as 0.59 for Tab L and 0.58 for Tab S. This indicates that the release mechanism is non-Fickian diffusion controlled. In addition, the curdlan tablets or theophylline powder were administered orally to 5 healthy volunteers, and saliva concentrations of theophylline were determined. Each saliva concentration was converted to plasma concentration using the saliva to plasma ratio of the drug in each subject. The AUC of Tab L was nearly the same as that of powder, while the AUC of Tab S was smaller than that of powder. The mean residence times (MRTs) of theophylline powder, Tab S and Tab L were 11.1 +/- 1.5, 25.4 +/- 6.3 and 17.1 +/- 1.5 h (N = 4-5, mean +/- S.D.), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Computed tomographic evaluation of lymph node metastasis in head and neck carcinomas

A retrospective study of 53 patients was undertaken to evaluate the efficacy of computer tomography (CT) in the detection of nodal metastases from carcinomas of the head and neck. The CT findings of 53 patients with head and neck carcinomas who underwent a total of 57 neck dissections were compared with the findings of physical examination (PE) and histopathological examination. Using node size larger than 10 mm in the short-axis diameter or the presence of central lucency as the criteria of nodal metastasis CT scanning staged correctly 52 of 57 necks, providing an accuracy of 91%, a sensitivity of 86% and a specificity of 100% in the detection of nodal metastases. There was agreement of PE findings with histology in 43 (74%) of 57 necks, with a sensitivity of 97% and a specificity of 38%, respectively. Because CT scanning was superior to PE in the pre-operative staging of head and neck carcinomas, it should be used for pre-operative evaluation of metastatic neck disease.

Augmentation of coronary responsiveness to serotonin at the site of X-ray-induced intimal thickening in miniature pigs

OBJECTIVE

X-irradiation is known to enhance atherosclerotic change. We tested whether coronary vasoconstrictor responses are augmented at the sites of X-ray-induced intimal thickening in Göttingen miniature pigs.

METHODS

In 17 pigs, a major branch of the left coronary artery was denuded with a balloon catheter. In 10 pigs, the denuded portion of the left coronary artery was selectively irradiated with 15 Gy of X-rays twice at 3 and 4 months after denudation (group 1). The remaining 7 pigs were not irradiated (group 2). The effects of intracoronary administration of serotonin, histamine and phenylephrine on the coronary diameter were studied 3 (3M) and 5 months (5M) after denudation. After the angiographical study at 5M, the vessels were isolated and isometric tension was measured in an organ chamber.

RESULTS

The percent reduction in coronary diameter evoked with 10 micrograms.kg-1 of serotonin increased from 39(s.e.m. 4)% before X-irradiation (3M) to 75(6)% after X-irradiation (5M) in group 1 (P < 0.01), while it did not differ in group 2 [39(6)% at 3M vs. 33(8)% at 5M[ [39(6)% at 3M vs. 33(8)% at 5M]. In group 1, serotonin-induced coronary constriction was frequently accompanied by ischemic ECG changes. Histamine (10 micrograms.kg-1)-induced vasoconstriction was also augmented but to a smaller degree [47(6)% at 3M vs. 62(4)% at 5M; P < 0.05] in group 1, while it remained unchanged in group 2[52(5)% at 3M vs. 44(7)% at 5M]. Phenylephrine did not cause detectable contraction in either group at 3M or 5M. Methysergide and ketanserin attenuated serotonin-induced hypercontraction in a dose-dependent fashion. In the in vitro studies, endothelium-dependent relaxation to serotonin was impaired at the denuded site with (group 1) and without (group 2) X-irradiation to a similar extent. Isometric tension of medial smooth muscle developed by serotonin was significantly greater at the denuded site with X-irradiation (group 1) than the control site and the denuded site without X-irradiation (group 2) (P < 0.05). Intimal thickening was significantly greater at the denuded sites with X-irradiation [group 1, 238(45) microns] than at the denuded sites without X-irradiation [group 2, 58(5) microns] (P < 0.05).

CONCLUSIONS

These results indicate that X-irradiation augments the coronary vasoconstrictor responses to autacoids, predominantly to serotonin, and that this augmentation is accompanied by enhanced intimal thickening. Serotonin-induced hypercontraction after X-irradiation resulted mainly from the hyperreactivity of medial smooth muscle.

Apoptotic cell death triggered by nitric oxide in pancreatic beta-cells

Nitric oxide (NO) is believed to be an effector molecule that mediates interleukin (IL)-1 beta-induced destruction and dysfunction of pancreatic beta-cells. We have demonstrated that both exogenous NO and NO generated endogenously by IL-1 beta brought about apoptosis of isolated rat pancreatic islet cells as well as pancreatic beta-cell tumor-derived cell line HIT. This apoptosis was characterized by cleavage of DNA into nucleosomal fragments of 180-200 bp and morphologically by nuclear shrinkage, chromatic condensation, and apoptotic body formation. The IL-1 beta-induced internucleosomal DNA cleavage occurred in a time- and dose-dependent manner. Actinomycin D, cycloheximide, and nitric oxide synthase inhibitors inhibited the DNA cleavage, which was correlated with the amount of NO produced, indicating that NO produced by HIT cells themselves could mediate the apoptosis. Furthermore, in the presence of tumor necrosis factor (TNF)-alpha, large amounts of NO were produced by IL-1 beta and DNA cleavage occurred more noticeably, although TNF-alpha alone did not generate NO. Streptozotocin (STZ), a diabetogenic reagent containing a nitroso moiety, also released NO and induced internucleosomal DNA cleavage in HIT cells. These results suggest that NO-induced internucleosomal DNA cleavage is an important initial step in the destruction and dysfunction of pancreatic beta-cells induced by inflammatory stimulation or treatment with STZ.

Interleukin-3-associated expression of gangliosides in mouse myelogenous leukemia NFS60 cells introduced with interleukin-3 gene: expression of ganglioside GD1a and key involvement of CMP-NeuAc:lactosylceramide alpha 2-->3-sialyltransferase in GD1a expression

Murine interleukin-3 (IL-3)-associated expression of gangliosides has been investigated using a gene transfection technique. A murine IL-3 cDNA was introduced into the parental NFS60-17 cells that was exclusively dependent on IL-3. We analyzed the glycosphingolipids from the parental cells and the transfected cells by fast atom bombardment mass spectrometry analyses and/or immunostaining techniques using specific antibodies. Two major gangliosides, IV3NeuAc-GgOse4Cer (GM1b) and IV3-NeuAc,III6NeuAc-GgOse4Cer (GD1 alpha), were expressed, in the parental cells. By contrast, in the IL-3 gene-transfected cells, a ganglioside IV3NeuAc,II3NeuAc-GgOse4Cer (GD1a) was strikingly expressed, in addition to GM1b and GD1 alpha that were already present in the parental cells. In spite of various IL-3-secreting capabilities, all transfectants investigated have exhibited the same ganglioside patterns and expressed GD1a. Furthermore, the appearance of GD1a was a consequence of the up-regulation of a single glycosyltransferase, CMP-NeuAc:lactosylceramide alpha 2-->3-sialytransferase (GM3 synthase). Activities of the other downstream glycosyltransferases that were involved in GD1a synthesis were not significantly different between the parental and the transfected cells. According to these data, the progression of tumor stage by the acquisition of autonomous cell growth ability after IL-3 gene transfection resulted in dramatic changes in cell surface gangliosides and their biosynthetic pathways. GD1a could be considered as an IL-3-associated ganglioside and was expressed in a tight connection with a single glycosyltransferase (GM3 synthase) up-regulation and with IL-3 expression in murine myelogenous leukemia cells.

[A familial case of ADPKD with intracranial aneurysms detected by MR angiography]

The management and screening of unruptured asymptomatic intracranial aneurysm (ICA) in patients with ADPKD and those with a family history of ICA remains a subject of considerable controversy. In recent years, it has been revealed that MRA (magnetic resonance angiography) can define the circle of Willis to allow detection of ICA as small as 3-4 mm. We report a case of a 63-year-old man with ADPKD and his family. No definite aneurysm was observed by angiography screening at 46 years of age, when he was referred for hemodialysis. For the past three years, his family history revealed that three relatives were suffering from subarachnoid hemorrhage at the ages of 32, 36 and 39 years, respectively, two of whom had ICA and one had arterio-venous malformation detected by angiography. Whether they had ADPKD was unknown, but two were suggestive of ADPKD. Therefore, our case underwent MRA as screening for ICA, which showed an ICA with a diameter of 5mm in the anterior communicating artery. The ICA was confirmed as being 6 mm in diameter by conventional angiography. His niece and her son, who had ADPKD, also underwent MRA, which showed a suspicious image of a 2 mm ICA in the latter case. These results suggest that prophylactic screening for ICA is important in an ICA clustering family. MRA is useful in screening for ICA and in the follow-up study on the natural course of ICA.

[Two cases with metastatic intracerebral alveolar soft part sarcoma]

The alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor which usually occurs in the lower extremity of young girls. The incidence of metastasis is said to be highest in the lung (38%), and second highest in the bone and brain (33%). This report describes two cases of metastatic intracerebral alveolar soft part sarcoma, originating in the lower extremity. A female patient noticed a painless swelling in her right leg at the age of 11, and 10 years later she underwent total removal of the tumor. The diagnosis was alveolar soft part sarcoma. At 37 she was admitted to our service with a diagnosis of cerebral metastasis in the left frontal lobe. Since then she has undergone surgical removal 4 times for recurrent cerebral metastasis and twice for lung metastasis. Now she is 55 years old and doing well except for mild left hemiparesis. She survives without cerebral or general metastasis 44 years following the onset of the sarcoma in her right leg and 18 years following the onset of the metastatic brain tumor. A 30-year-old man, who noticed a painless swelling in his left thigh in January 1991, underwent total removal of the tumor and the diagnosis was alveolar soft part sarcoma. He was admitted to our service with no neurological deficits in October 1992, but a CT scan showed a metastatic brain tumor in the left parieto-occipital region. Total removal of this metastatic brain tumor was successfully performed in November 1992. However, he died because of multiple brain and lung metastasis in February, 1994.(ABSTRACT TRUNCATED AT 250 WORDS)

Macrophage colony stimulating factor inhibits experimental liver metastases from colon cancer

This study investigated the inhibitory effect of human macrophage colony stimulating factor (hM-CSF) on experimental liver metastases. Murine colon cancer cell lines C-26 and C-36 were each injected into the spleen of BALB/c mice and the number of subsequent liver metastases was counted. An optimal dose (3,000U/body/day) of hM-CSF to inhibit liver metastases was identified. Additionally, hM-CSF (3,000U/body/day) administration for 7 days before and after the injection of the same cancer cell lines was investigated. The mean number of liver metastases decreased significantly in the hM-CSF group compared with the saline group. These results suggest potential therapeutic benefit for the use of hM-CSF in the adjuvant treatment of liver metastases.

[Development and evaluation of self-study material for smoking prevention education]

A booklet for smoking prevention education was developed for junior high school students, which is a role-play activity book for self-study and discusses not only the harmful effects and dependency of smoking but also psychosocial factors affecting smoking behavior among students. The purpose of this material is to provide students with basic information needed to choose a non-smoking lifestyle even without a teacher's direct instruction. Process evaluation and impact evaluation studies were carried out between September 1991 and September 1992. Six hundred sixty-nine students and 9 teachers from three junior high schools in Osaka, Tokyo and Yamagata participated in the process evaluation study. More than 90% of the students were able to complete the material in one school hour and less than 4% students expressed difficulty in learning from the booklet. Nine hundred seventy-seven students from 2 junior high schools in Tokyo participated in an intervention study to evaluate the effectiveness of the material. There were 500 students in the experimental school and 477 students in the control school. All students were given a pretest and posttest, 2 months apart. Knowledge concerning smoking increased and attitudes toward smoking were modified significantly in the experimental school. However, intention to smoke and smoking behavior did not change significantly, due to the small numbers of students with intention to smoke at the time of pretest and because there was not enough time for their intention to change. This study demonstrates the effectiveness of the material in junior high school. However, teacher participation during the instruction is also seen to be necessary for greater effect.

Ultrastructure and x-ray microanalytical study of human pineal concretions

We examined human pineal concretions and found them to exhibit a multi-layered concentric structure consisting of irregularly spaced dense and sparse zones containing fine crystals. The hydroxyapatite crystallites were shown to be irregularly outlined plate forms (measuring 11-70 nm in their longest dimension and 2-10 nm in thickness). At the center of each crystallite a central dark line was observed by means of high resolution electron microscopy. The structure and size of the crystals were similar to those of dentin and bone. The ground surface of the concretions was observed metallurgically by means of an electron probe microanalyzer (EPMA). The surface zones of the concretions contained a higher concentration of zinc, which seems to play an important role during the mineralization process, whereas calcium and phosphorus exhibited higher concentrations at the center.

Establishment and structural analysis of human mAb to the E2 component of the 2-oxoglutarate dehydrogenase complex generated from a patient with primary biliary cirrhosis

We established one Epstein-Barr virus-transformed B cell hybrid clone producing human mAb of the IgG class to the 2-oxoglutarate dehydrogenase complex (OGDC) for the first time from the peripheral B lymphocytes of a patient with primary biliary cirrhosis (PBC). This mAb, designated mAbM37GO37, specifically bound to OGDC and its dissociation constant with OGDC was calculated to be 3.70 x 10(-10) mol/l. mAbM37GO37 stained murine stomach/kidney cryostat sections in a typical immunofluorescence pattern of antimitochondrial antibody (AMA). Western blotting analysis revealed that mAbM37GO37 reacted with an E2 component of OGDC but not with other components of OGDC nor pyruvate dehydrogenase complex (PDC). Furthermore, mAbM37GO37 completely inhibited the enzymatic activity of OGDC. In order to determine the structure and genetic origin of anti-OGDC autoantibody, we cloned and sequenced the Ig heavy and light chain variable regions of mAbM37GO37. This mAb used the VHIII family member, V3-7, and the V kappa IV family member. The amino acid difference between the expressed V genes of this mAb and respective putative germline genes was concentrated within the complementarity determining regions (CDR) rather than the framework regions (FR). The R:S mutation ratio was high in the CDR and low in the FR. These features suggested that the immune response to OGDC is similar to that to exogenous antigen, and that the heavy and light chain variable regions of the anti-OGDC antibody undergo somatic hypermutation through antigen-driven clonal selection. This human mAb to OGDC, which was established for the first time from a patient with PBC and characterized at the molecular level, would be a valuable tool to study the B cell autoepitopes of OGDC, to clone as yet undetermined full length cDNA encoding OGDC and to dissect the autoimmune response to mitochondrial antigens in PBC.

[A case of renal cell carcinoma in a young adult]

Renal cell carcinoma in young adults under the age of forty is rare. A case of renal cell carcinoma in a 22-year-old female is presented. Microhematuria was pointed out in the patient by a health check up system and an ultrasonogram revealed a solid mass 5 cm in diameter in the lower pole of the right kidney. The patient was referred to our clinic in January, 1994. An abdominal CT showed a solid and well bordered mass in the right kidney. Renal tumor biopsy was revealed renal cell carcinoma. Right radical nephrectomy was performed on February 9, 1994. From 1986 to 1994, 4 cases of renal cell carcinoma in young adults, other than this case, have been treated in our clinic. All of them have been healthy for more than 6 years, suggesting a good prognosis.

Keratinocyte growth factor accelerates corneal epithelial wound healing in vivo

PURPOSE

To examine whether the topical application of keratinocyte growth factor (KGF) can enhance corneal epithelial healing in vivo. In addition, the distribution of S-phase cells in KGF-treated and control corneas was investigated during regeneration and under normal conditions.

METHODS

A 10-mm diameter epithelial defect was made in the center of rabbit corneas. A 50-microliters aliquot of 10 micrograms/ml human keratinocyte growth factor (hKGF) was then applied topically five times a day. The same volume of phosphate-buffered saline (PBS) vehicle was applied to the contralateral eye as a control. Each corneal epithelial defect was subsequently photographed every 12 hours and was measured by a computer-assisted digitizer. For the S-phase cell analysis, entire corneas were labeled with 3H-thymidine and were subjected to autoradiography at 24 hours after wounding or in the normal cornea at 24 hours after the application of KGF or PBS.

RESULTS

Topical application of 10 micrograms/ml hKGF significantly accelerated corneal epithelial wound healing when compared with controls. In the S-phase cell analysis, KGF did not have any effect on normal corneal epithelial cells. However, in the regenerating cornea, the number of S-phase cells in the KGF-treated limbal epithelium was twofold higher than in the controls.

CONCLUSIONS

Topical application of KGF accelerated corneal epithelial wound healing in vivo and increased cell proliferation in the limbal epithelium of the regenerating cornea.

[Localization of Mn-SOD mRNA in rat cornea by in situ hybridization]

We investigated the localization of Mn-SOD mRNA in the rat cornea under physiological conditions using in situ hybridization. A Mn-SOD cDNA probe was synthesized by polymerase chain reaction. Slot blot analysis was performed to confirm that the cDNA probe hybridizes with rat Mn-SOD mRNA. Frozen sections of rat cornea were subjected to in situ hybridization using 3H-labeled Mn-SOD cDNA probe. The results demonstrated the expression of Mn-SOD mRNA in the rat corneal epithelial layer. We suggest that corneal epithelial cells are constantly exposed to active oxygen stress even under physiological conditions and synthesize Mn-SOD to protect themselves from the stress.

Acute and subacute toxicity tests of madder root, natural colorant extracted from madder (Rubia tinctorum), in (C57BL/6 X C3H)F1 mice

As part of the safety assessment of madder root (MR), a food colorant extracted from madder (Rubia tinctorum), toxicity tests were undertaken using (C57BL/6 x C3H)F1 mice of both sexes. An acute toxicity test was performed by 14-day administration of MR dissolved in distilled water by gavage at doses of 0, 500, 2000, 3500, and 5000 mg/kg body weight to groups of each sex. One male mouse dosed at 5000 mg/kg body weight was dead before the end of the study, indicating that the maximum tolerated dose of MR was between 3500 and 5000 mg/kg body weight. A subacute toxicity test of MR was performed using 62 mice of each sex, mixing their diets with MR at concentrations of 0, 0.3, 0.6, 1.25, 2.5, and 5% for 90 days. All mice tolerated these doses of MR well. The body weight gains of either sex were not affected by the treatment. None of the mice treated with MR showed clinical signs of toxicity. Histopathological examinations showed retention cysts of the kidneys and epidermal vaginal cysts in a few of the treated or control mice. No hyperplastic, preneoplastic, and neoplastic lesions and no pathological findings of toxicity were found. These results suggest that dietary exposure of MR at these doses has no acute or subacute toxic effects on mice.

[Inoculum sizes necessary for maintaining the activity of Mycobacterium leprae in cell-free liquid media]

Evidence was presented in the previous paper that the activity of cells of Mycobacterium leprae was maintained in the phosphate buffer(pH 7) containing fetal calf serum (10%) with/without glycerin (2%) for approximately 4 weeks during incubation of cells at 30 degrees C, when the inoculum having more than 3,000 pg ATP was used. In the present paper, it is confirmed that the definite inoculum sizes are essential for obtaining the reproducible results that are described above, by using the inocula containing more and less than 3,000 pg ATP.