Suppressive effect of FK-506, a novel immunosuppressant, against MPTP-induced dopamine depletion in the striatum of young C57BL/6 mice

Systemic injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is known to damage the dopaminergic nigrostriatal system in C57BL/6 mice. We have investigated the effects of immunosuppressants, FK-506 and cyclosporin A (CsA), on MPTP-induced dopamine (DA) depletion in the striatum of young C57BL/6 mice. 10 days after MPTP treatment (25 mg/kg i.p. given daily, 5 days), DA in the striatum was depleted by 80%. However, pretreatment with FK-506, a novel immunosuppressant, significantly protected MPTP-induced DA depletion in the striatum, but FK-506 itself did not affect the DA content. CsA, another immunosuppressant, also protected MPTP-induced DA depletion. From these results can be seen that immunosuppressants seem to inhibit MPTP neurotoxicity toward nigrostriatal dopaminergic neurons of young C57BL/6 mice.

[Phase II study of CGS16949A, a new aromatase inhibitor--a dose finding study]

A dose finding phase II study of a novel aromatase inhibitor CGS16949A was performed in postmenopausal patients with advanced breast cancer. The daily dose of 1 mg (0.5 mg b.i.d.), 2 mg (1 mg b.i.d.) or 4 mg (2 mg b.i.d.) CGS16949A was administered orally for 8 weeks or more on dose escalation schedule. The response rates (CR+PR) in the evaluable cases were 13.6%, 22.0% and 13.3% in 1 mg/day group (1 mg group), 2 mg/day group (2 mg group) and 4 mg/day group (4 mg group), respectively. There was no statistically significant difference in the response rates among the three treatment groups. Median time to the onset of PR was 99, 113 and 114 days in 1 mg, 2 mg and 4 mg group, respectively, and the median duration of response was 276 days, 391 days and 277 days in 1 mg, 2 mg and 4 mg group, respectively. Five patients in each treatment group showed prolonged stabilization of disease ("long NC", lasting > or = 6 months). Median durations of stabilization were 223 and 241 days in 2 and 4 mg group respectively. The incidence of adverse effects were 11.9%, 7.5% and 13.0% in 1 mg, 2 mg and 4 mg group respectively, and 30 out of 33 symptoms (90.9%) were of mild. Laboratory abnormalities were observed in 12.2%, 22.9% and 23.8% in the respective groups of 1, 2 and 4 mg, and no patient experienced clinical symptoms related to these changes. Plasma estradiol concentration at one month after initiation of the treatment decreased significantly in comparison with pretreatment levels, and was slightly exceeding the limit of detection. Plasma cortisol was not changed. As shown in this results, CGS16949A showed sufficient efficacy and good tolerability in postmenopausal patients with advanced breast cancer. It was considered that the optimal dose in clinical use judged as 2 mg/day.

[Late phase II study of CGS16949A, a new aromatase inhibitor--a multicentral cooperative study (Western Japan Group)]

A late phase II study of a new non-steroidal aromatase inhibitor CGS16949A was performed in postmenopausal patients with advanced or recurrent breast cancer. The drug was given orally, 1 mg twice daily for 12 weeks or more. Of 72 evaluable cases, there were 1-CR, 10-PR, 17-"long NC", 12 NC and 32-PD, with "long NC" defined as disease stabilization for more than 6 months. Median time to the onset of PR and median duration of objective tumor responses were 85 and 278 days, respectively. Maximum and median duration of long NC were 471 and 243 days, respectively. Adverse effects were observed in 5 (7.8%) of 64 cases. In laboratory evaluations, slight abnormalities were observed in 11 (17.2%) of 64 cases. No adverse effect and laboratory abnormality was found worse than Grade 1 toxicity. As for Global Utility Rating, treatment with CGS16949A was considered to be useful or better in 24 (32.9%) of 73 cases. Plasma estradiol and estrone concentrations at one month after initiation of the treatment decreased significantly in comparison with pre-treatment levels. Plasma cortisol, testosterone and androstenedione was not changed. Thus, CGS16949A showed good efficacy, tolerability and usefulness in postmenopausal patients with advanced or recurrent breast cancer.

[Evaluation of the effects of vibro-acoustic stimulation test on the fetus during labor under epidural analgesia and evidence of its safety by way of auditory brainstem response]

This study was undertaken to elucidate the effects of epidural analgesia on vibro-acoustic stimulation test (VAST) during normal labor and auditory brainstem response (ABR) in fifty full term parturients without any complication. The safety of VAST in relation to the ABR of neonates was also studied. The results were as follows, 1) There were some changes in CTG monitoring in five cases (10%) in the 10 minutes after epidural analgesia. However, these changes were not ominous signs but all related to the coiling of the cord, as previously reported. 2) The ABR latency-intensity curve (audio-function of the newborn infants) revealed no hazardous change in VAST-loaded infants or in the controls. The response threshold was 10dB in this study. The application of VAST to the parturients under epidural analgesia was therefore not only harmless to the fetuses but also a useful way to evaluate fetal well-being.

[Effects on hemodynamics and myocardial metabolism of nicardipine and nitroglycerin during aortic cross clamp in dogs with experimentally produced coronary stenosis]

We investigated the effects of hemodynamics and myocardial metabolism of nicardipine (NIC) and nitroglycerin (NTG) in experimentally coronary constricted dogs. Coronary constriction was produced by reducing 50% of the left anterior descending coronary blood flow. After stabilization of hemodynamics, we cross-clamped the descending aorta and administered nicardipine (10 micrograms.kg-1.min-1) or nitroglycerin (10 micrograms.kg-1.min-1). The drugs were infused for 15 minutes and were discontinued just before the clamp on the aorta was released. In NIC group, the cardiac output (CO) increased 32% and the heart rate (HR) decreased 17% significantly, compared with pre-clamping values. The myocardial blood flow (MBF) in ischemic area measured by hydrogen clearance method was maintained. The value of the myocardial oxygen extraction ratio (MO2EX) decreased significantly for 24.3% compared with the pre-clamping value of 41.4%. On the other hand, in NTG group, CO, HR, and MO2EX were unchanged, but MBF in ischemic area was well maintained. The results of these experimentally coronary constricted dogs suggest that both NIC and NTG maintain the cardiac function during the aortic cross-clamping, but regarding the improvement of the myocardial metabolism, NIC appears to be the better choice for blood pressure control.

[Phase I study of CGS16949A--a new aromatase inhibitor. Cooperative Study Group for CGS16949A]

Phase I study of CGS16949A--a new aromatase inhibitor--was performed in postmenopausal women with advanced breast cancer who received either single oral administration of 4 and 8 mg, or multiple oral daily administration of 1, 2, 4, 8 and 16 mg for 5.5 days. No side effects were observed after single dose administration of 4 mg and 8 mg of CGS16949A. In the multiple administration, one patient received 1 mg/day for 3 days complained of abdominal pain (Grade 2), but administration of CGS16949 A was continued despite of the pain. In order to assess the causal relationship of the drug with the abdominal pain, the number of patients in 1 mg/day group was doubled from 3 to 6 patients, but no side effects were observed in the remaining five patients. In addition, no side effects, including abdominal pain, were noted in the other 2, 4, 8 and 16 mg/day groups. After multiple administration, plasma concentrations of estradiol at 5 hrs after the final dosage in the respective dose groups were reduced to 47.1 +/- 8.3%, 37.3 +/- 3.0%, 28.0 +/- 7.8%, 26.0 +/- 11.3% and 26.6 +/- 13.8% respectively. Similar tendencies were observed in estrone plasma levels and urinary estrogens levels. In this study, the reduction of plasma estrogen levels was confirmed following administration of CGS 16949A. The clinical usefulness of this new aromatase inhibitor remains to be studied further.

Diffusional anisotropy of the human brain assessed with diffusion-weighted MR: relation with normal brain development and aging

PURPOSE

To analyze diffusional anisotropy in frontal and occipital white matter of human brain quantitatively as a function of age by using diffusion-weighted MR imaging.

METHODS

Ten neonates (< 1 month), 13 infants (1-10 months), 9 children (1-11 years), and 16 adults (20-79 years) were examined. After taking axial spin-echo images of the brain, diffusion-sensitive gradients were added parallel or perpendicular to the orientation of nerve fibers. The apparent diffusion coefficient parallel to the nerve fibers (0) and that perpendicular to the fibers (90) were computed. The anisotropic ratio (90/0) was calculated as a function of age.

RESULTS

Anisotropic ratios of frontal white matter were significantly larger in neonates as compared with infants, children, or adults. The ratios showed rapid decrease until 6 months and thereafter were identical in all subjects. In the occipital lobe, the ratios were also greater in neonates, but the differences from other age groups were not so prominent as in the frontal lobe. Comparing anisotropic ratios between frontal and occipital lobes, a significant difference was observed only in neonates.

CONCLUSIONS

Diffusion-weighted images demonstrated that the myelination process starts earlier in the occipital lobe than in the frontal lobe. The changes of diffusional anisotropy in white matter are completed within 6 months after birth. Diffusion-weighted imaging provides earlier detection of brain myelination compared with the conventional T1- and T2-weighted images.

Inhibitory effects of botulinum toxin on 5-HT1C receptor-induced Cl- current in Xenopus oocytes

Several low molecular weight G proteins have been identified, but their functional roles remain unclear. To clarify the involvement of low molecular weight G protein in receptor-stimulated turnover of polyphosphoinositide (PI) turnover, influences of botulinum toxins on serotonin (5-HT)-stimulated Cl- current mediated by PI turnover were investigated using Xenopus oocytes injected with rat brain mRNA. Treatment with botulinum toxin C, D or purified ADP-ribosyltransferase of botulinum toxin (botulinum toxin C3 enzyme) inhibited the 5-HT-induced Cl- current in oocytes, and ADP-ribosylated 23 kDa proteins. Both botulinum toxin C3 enzyme-induced inhibition of the current and ADP-ribosylation were suppressed by pretreatment with antibotulinum toxin C3 enzyme antibody. Botulinum toxin D treatment of oocytes was ineffective in the response of Cl- current induced by injection of 50 pmol inositol 1,4,5-trisphosphate and 50 pmol Ca2+. It is suggested that low molecular weight G proteins ADP-ribosylated by botulinum toxin C3 enzyme are involved in phospholipase C activation in Xenopus oocytes.

Unilateral hearing loss following rubella infection in an adult

A 36-year-old man was admitted to our university hospital, complaining of acute hearing loss of the right ear, which was his only hearing ear. He had developed complete deafness due to mumps in the left ear at the age of 26. Before admission, he had been diagnosed as having rubella infection. He noticed hearing loss in the right ear two days after disappearance of macular rash. Headache, nausea and vertigo were not present. Three weeks after the onset of hearing loss, he was admitted to our university hospital. Pure tone audiometry revealed sensorineural hearing loss; a mild ascending audiometric curve with a marked loss at 4,000 Hz and 8,000 Hz. SISI test was positive. Caloric stimulation (ice water 10 ml/10 s) to the right ear demonstrated a normal response. Rubella hemagglutination antibody titer was 512. Specific IgG antibody was over 3,200. Specific IgM antibody was positive (7.01 Enzyme Immunoassay). The data indicated recent infection with rubella. He was given betamethasone for 14 days. Pure tone audiometry showed hearing improvement.

Hormone-dependent enhancement in binding of oto- and nephrotoxic aminoglycoside antibiotics

Intraperitoneal administration of gentamicin (40 mg/ml) to the guinea pig is known to cause damage of the tissue of the kidneys and auditory organs. By indirect immunohistochemical staining with anti-gentamicin antiserum, those cells with high affinity to gentamicin in the auditory organs and kidneys were the hair cells in the cochlea and the epithelial cells in the renal tubules. The concentrations of gentamicin in the serum and perilymph of the guinea pig with tissue damage were found to be 2 and 0.6 mg/ml at the maximal levels, respectively, by high performance liquid chromatography. The same concentration of gentamicin, 2 mg/ml, also inhibited cell growth and resulted in cell damage of the renal tubule-derived cell lines, JTC-12 and MDCK. Among the antibiotics examined, i.e. streptomycin, gentamicin, fradiomycin and kanamycin, gentamicin showed the strongest effect on growth inhibition of the renal tubule-derived cells, when these cells were cultured in a medium with 5% fetal calf serum. Although the number of JTC-12 cells in the medium without fetal calf serum remained the same for a week, even with the addition of either gentamicin (0.5 mg/ml) or parathyroid hormone (2 mM) the coadministration of gentamicin and parathyroid hormone resulted in a loss of cells due to cellular death, and the amount of gentamicin bound onto the cells cultured with gentamicin plus parathyroid hormone was significantly higher than that with gentamicin alone. These results indicate that the expression of the receptor for gentamicin on the cell surface is greatly enhanced by hormonal stimulation.

Chronic desipramine treatment influences D1 stimulation and D2 inhibition (dual control) of adenylate cyclase by dopamine in rat striatum

The response of adenylate cyclase to GTP and to dopamine (DA) was investigated in striatal membranes from desipramine (DMI)- or saline-treated rats. DMI (15 mg/kg) or saline was injected i.p. once a day for 3 weeks. In saline-treated control membranes, GTP exerted a biphasic effect on basal and DA-stimulated enzyme activity; peak levels of stimulation by DA plus GTP were observed at 1 microM GTP. On the other hand, peak levels moved to the right in the GTP dose response curve in DMI-treated membranes. Therefore, D2 inhibition might be attenuated, while the D2 specific agonist, PPHT, was not observed to cause inhibition of adenylate cyclase. Furthermore, D1 stimulation of adenylate cyclase via D1 specific agonist SKF was attenuated in DMI-treated membranes. It seems, therefore, that chronic treatment of rat striatum with DMI exerts a dual influence, that is, a lessening of both D1 stimulation and D2 inhibition of adenylate cyclase, and alters specifically the overall process of the adenylate cyclase system.

Perilymph fistula: concept, diagnosis and management

Perilymph fistula is caused by changes of cerebrospinal fluid pressure and/or middle ear pressure. For diagnosis, history taking is extremely important in regard to whether the occurrence of symptoms is related to physical exertion, such as straining, nose blowing, sneezing etc. A variety of symptoms are due to pathologic changes of the membranous labyrinth. Exploratory tympanotomy is needed to verify the occurrence of leakage. However, perilymph fistula cannot be excluded, even if leakage is not observed. Management consists of absolute rest and closure of the fistula. If dizziness or vertigo is intractable and long-lasting, destruction of vestibular function should be considered.

Development of atherosclerosis in alloxan diabetic rats

Rats with alloxan-induced diabetes developed severe atherosclerotic lesions when they were maintained on a 0.25% cholesterol diet for one year. The atheromatous changes developed at the aortic arch, appeared as early as 3 months after the start of the experiment, and increased thereafter. The diabetic rats also developed atherosclerosis when they were fed standard rat chow, but the area of the atheromatous lesion was about one tenth of that in rats fed the high-cholesterol diet. Normal rats did not develop atherosclerosis even when fed the high-cholesterol diet for one year. The alloxan diabetic rats showed no increase in body weight, but developed serum glucose levels as high as 600-800 mg/dl as well as high serum cholesterol levels and lower serum HDL-cholesterol levels. The development of atherosclerosis in these rats was significantly related to an increase in the serum cholesterol/phospholipid ratio, the atherogenic index (TC-HDLC/HDLC), and the serum total cholesterol level, but was not related to the serum glucose, HDL-cholesterol, triglyceride, or lipid peroxide levels. These relationships were found as early as B-16 weeks after the start of the experiment. These data suggest that the serum cholesterol/phospholipid ratio, the atherogenic index, and the total cholesterol level are important risk factors for the development of atherosclerosis in rats with alloxan diabetes.

Reduction of drug accumulation in cisplatin-resistant variants of human prostatic cancer PC-3 cell line

We have isolated cis-diamminedichloroplatinum (II) (CDDP)-resistant variants, P/CDP4 and P/CDP5, from human prostatic cancer PC-3 cells after a stepwise exposure to CDDP. P/CDP4 and P/CDP5 showed 11-fold and 23-fold higher resistance to CDDP than did PC-3. P/CDP5 was cross-resistant to carboplatin, mitomycin C, etoposide, m-AMSA, bleomycin and UV irradiation. Alkaline elution of DNA showed an increased amount of DNA interstrand cross-links in PC-3 but not in P/CDP5 when PC-3 and P/CDP5 were cultured with CDDP. Flameless atomic absorption spectrophotometry revealed that intracellular accumulation of CDDP in P/CDP4 and P/CDP5 was decreased to 18 to 34% and 9 to 18% of that of PC-3, respectively, when PC-3 and its CDDP-resistant counterparts were incubated with 5 and 10 micrograms./ml. of CDDP for 24 hours. These data suggest that decreased drug accumulation is involved in the development of CDDP-resistance in the PC-3 cell line.

[A new approach to intra-arterial infusion chemotherapy for breast cancer]

To perform intra-arterial infusion chemotherapy for breast cancer, we cannulated the internal thoracic and lateral thoracic arteries, respectively. In the past, we could catheterize the former vessel only 43% of the time using gross observation, but now we can do so 100% of the time with an operating microscope apparatus. It was selectively done in the latter vessel through the brachial artery after the Seldinger method. An 82-day-long intra-arterial chemotherapy could be continued without any restriction in the patient's daily life, and the tumor decreased in size considerably. Nevertheless, intra-arterial preservation of the catheter and administration of anticancer drugs decrease local blood flow and produce thromboangitis, resulting in an extremely hypovascular state of tumor lesion. These changes, observed both angiographically and fluorographically, pose problems which must be resolved for long-term intra-arterial infusion chemotherapy.

Inducible nitric oxide synthase in glial cells

Nitric oxide (NO), a free radical gas, has been suggested to mediate both synaptic plasticity and neuronal death. NO is generated by constitutive and inducible types of NO synthase (cNOS and iNOS, respectively). The neuronal cNOS was recently cloned, sequenced and characterized. In contrast, properties of iNOS in the brain are not fully understood. It is noted that glial cells can form NO and that microglial and reactive astroglial cells are accumulated around neurodegenerative sites in the brain, suggesting a relationship between neuronal injury and NO originated from glial cells. We found that several stimuli such as endotoxin (lipopolysaccharide) and cytokines induced iNOS in glial cells of rat brain. This article reviews recent findings on characteristics and the induction mechanism of iNOS in the glial cells, and discusses the possible pathophysiological functions of iNOS in the brain.

Localization of a gene for Fukuyama type congenital muscular dystrophy to chromosome 9q31-33

Fukuyama type congenital muscular dystrophy (FCMD) is an autosomal recessive severe muscular dystrophy associated with an anomaly of the brain. Twenty-one FCMD families, 13 of them with consanguineous marriages, were analysed by genetic linkage analyses with polymorphic microsatellite markers to map the FCMD gene. Significant lod scores were obtained with the markers D9S58 (Zmax = 5.81 at theta = 0.06), D9S59 (Zmax = 4.33 at theta = 0.02), and HXB (Zmax = 3.28 at theta = 0.09) on chromosome 9q31-33. Multipoint analysis placed FCMD between D9S58 and D9S59, with a maximum lod score of 16.93. These markers will be useful for presymptomatic, prenatal and carrier diagnosis of family members carrying FCMD, and they represent important resources for the identification of a gene responsible for FCMD.

Estimation of myocardial damage in Kawasaki disease using antimyosin antibody

In a retrospective study, 121 children with Kawasaki disease (KD) were investigated to determine (i) the incidence of myocardial damage using the antimyosin antibody (AMA) titer; (ii) the differences in the electrocardiograms between the AMA-positive and -negative patients; and (iii) the effect of treatment with intravenous gamma globulin (IVGG) on the AMA. Comparisons were made with 117 normal children (controls). Patients with KD showed a significantly higher mean AMA titer and more patients were positive for AMA than the controls. The AMA titer in the KD group was not related to the presence of coronary artery lesions. Electrocardiograms obtained during the acute and the convalescent stage of KD revealed that patients positive for AMA had a significantly lower voltage of T wave in lead V6 at week four than at week two of illness, whereas patients negative for AMA showed no T wave change after week two. The group treated with IVGG showed a significantly lower AMA titer than that not given IVGG. These observations suggest that myocardial damage occurs in some patients with KD which is unrelated to the presence of coronary artery lesions and that the treatment with IVGG reduces the AMA titer in patients with KD.

Morphological change and destabilization of beta-actin mRNA by tumor necrosis factor in human microvascular endothelial cells

Tumor necrosis factor-alpha (TNF-alpha) produced morphological changes from a cobblestone-like shape into a spindle shape in human omental microvascular endothelial (HOME) cells and also a drastic rearrangement of actin filaments. Expression of beta-actin gene was diminished in HOME cells treated with TNF-alpha for 24 h. Northern blot analysis of the beta-actin gene demonstrated that the cellular level of beta-actin mRNA was decreased at 6-12 h after exposure to TNF-alpha. However, there appeared to be no changes in cellular mRNA levels of beta-tubulin, fibronectin, laminin B1, laminin B2, and laminin binding protein genes after treatment with TNF-alpha. Nuclear run-on assays showed increased transcription of the low-density lipoprotein receptor gene, but not of the beta-actin gene. These data suggested that the TNF-alpha-induced inhibition of beta-actin gene expression was not due to altered transcription activity. The degradation rates of beta-actin, plasminogen activator inhibitor-1, and epidermal growth factor receptor mRNAs were examined in the presence of actinomycin D. beta-Actin mRNA was found to be specifically destabilized in TNF-alpha-treated HOME cells, while other mRNA species were not. Coadministration of cycloheximide blocked the TNF-alpha-induced degradation of beta-actin mRNA. The TNF-alpha-induced destabilization of beta-actin mRNA and rearrangement of actin filaments are discussed in relation to the morphological changes in human microvascular endothelial cells.

Restriction endonuclease Aor13HI from Acidiphilium organovorum 13H, a new isoschizomer of BspMII: purification and characterization

A restriction endonuclease, Aor13HI, an isoschizomer of BspMII, was purified to homogeneity from cell extracts of Acidiphilium organovorum strain 13H. The enzyme has a molecular mass of 60,000 daltons and consists of two subunits identical in molecular mass of 30,000 daltons. Aor13HI endonuclease, like BspMII, recognizes the palindromic six-base sequence 5'-TCCGGA-3', and cleaves between the T and C to produce a four-base 5' extension. Aor13HI is not inhibited by dam-dependent methylation. The isoelectric point of the enzyme is 5.7. Aor13HI activity was maximum at pH 7.5, 100 mM KCl, 7.5-10 mM MgCl2, and 55 degrees C. The enzyme was stable up to 60 degrees C. The N-terminal amino acid sequence (30 residues) of Aor13HI did not show any similarity with the sequence of other restriction endonucleases reported.

The development of sleep-wakefulness rhythm in normal infants and young children

The development of circadian sleep-wakefulness rhythm was investigated by a longitudinal study of two normal newborns for two and a half years and by a transversal study of 182 normal infants and young children living in three different areas of Japan. The circadian rhythm became established before 4 months of age, and daytime sleep became concentrated within two time periods from 7 months of age, and then within a single peak from 14 months of age. The time period 00:00-04:00 developed into the "absolute sleep period" from 3 months of age, and the "absolute wakefulness period" appeared first in the time period 08:00-11:00 from 14 months of age, and then in the time period 16:00-21:00 from one and a half years of age. Establishment of circadian rhythm as indicated by the numbers of sleep epochs in daytime and in nighttime, and the longest continuous sleep or wakefulness periods reflect the development of the nervous system and were influenced by the change of light-dark in the environment. These parameters showed critical ages, but not sexual or regional differences. However, regional differences were found in the times of waking up in morning and falling asleep at night. This indicated the phase of the circadian rhythm was also influenced by natural and social environmental factors.

Benign breast disease as a breast cancer risk in Japanese women

A hospital-based retrospective cohort study of benign breast disease (BBD) as a risk factor of future breast cancer (BC) development was conducted. Four hundred and twenty-eight patients with biopsied BBD were followed-up for a median period of 8 years, together with age-matched women with normal breasts (normal control) and BC patients (cancer control), at the ratio of 1:2:2. Twenty-one breast cancers developed, 7 in the cases, 4 in the normal controls, and 10 in the BC controls, showing the relative risk (RR) with 95% confidence intervals (CI) to be 3.5 (1.03-11.9) in the cases with respect to the normal controls. The RR of the cases is not lower than that of contralateral breast cancer incidence. There were no significant differences in the risks of cancers in other organs among the groups. Pathological examination revealed that only atypical hyperplasia increased the RR of BC, as compared with the normal control breast group, or with non-proliferative disease. These results suggest that in a low-risk country, Japan, BBD is a definite risk factor for BC development as in high-risk countries.

Successful treatment of refractory polymyositis with pulse intravenous cyclophosphamide and low-dose weekly oral methotrexate therapy

A 36-year-old woman gradually developed dysphagia and muscle weakness of the lower extremities. Diagnosis of polymyositis was given from elevation of serum creatine kinase and pathological findings of a muscle biopsy. Despite oral prednisolone and intravenous pulse methylprednisolone therapy, her muscle weakness persisted, and then pulse intravenous cyclophosphamide (IVCY) therapy was initiated and repeated five times in total, which resulted in significant improvement in muscle strength. Thereafter, weekly administration of methotrexate at low dosage further normalized the serum creatine kinase level. We may conclude that IVCY and low-dose weekly methotrexate together could be an alternative in refractory polymyositis.

Prevention of overt diabetes and insulitis by intrathymic injection of syngeneic islets in newborn nonobese diabetic (NOD) mice

Based on previous studies showing that allogeneic islets transplanted into the thymus can induce donor-specific unresponsiveness, we investigated in the nonobese diabetic (NOD) mouse the effect of intrathymic islet isografts on preventing autoimmunity directed against pancreatic islet antigens. Islets prepared from newborn NOD pancreata were injected into one lobe of the thymus of 10- to 11-day-old female NOD mice (experimental group) with no immunosuppression. PBS alone was used for injection into age- and sex-matched litter mates (control group). Thirty of 32 (94%) experimental mice remained normoglycemic for over 30 weeks. Well-formed islets with no indication of insulitis were found in the thymus of these 30 mice, whereas no grafted islets were found in the 2 mice that became diabetic at 17 and 19 weeks, respectively (technical failures). In the control group, 10 of 32 (31%) mice became diabetic between 20 and 29 weeks. This diabetic incidence was, however, lower than that in our colony female mice. In the pancreas of experimental mice, 90.9% of islets were free of infiltrates, whereas only 13.1% of islets were intact in control mice. The spleens of 30-week-old experimental mice contained a slightly higher percentage of CD8+ T cells (P < 0.05) than those of control mice. Cyclophosphamide injections at 30 weeks induced diabetes in 4 of 9 experimental mice. The 2 lines of evidence, (1) marked reduction in insulitis of intrathymic islet-grafted mice and (2) induction of diabetes after treatment with cyclophosphamide, suggest that both thymic clonal deletion and peripheral tolerance may play a role in preventing diabetes.