Continuous inhibition of excessive polyol pathway flux in peripheral nerves by aldose reductase inhibitor fidarestat leads to improvement of diabetic neuropathy

We investigated the effects of three aldose reductase (AR) inhibitors, fidarestat, epalrestat and zenarestat, on the slowing of sensory nerve conduction velocity (SNCV), motor nerve conduction velocity (MNCV), and minimal F-wave latency prolongation in streptozotocin (STZ)-induced diabetic rats. Two weeks after STZ injection, SNCV and MNCV in the diabetic rats were significantly slower than in normal rats. Fidarestat (0.25-2 mg/kg/day), epalrestat (48 to 96 mg/kg/day) or zenarestat (10-40 mg/kg/day) was administered orally for the following 2 weeks, and SNCV, MNCV and F-wave latency were measured 3 h after final administration. Significant prolongation of minimal F-wave latency, as well as slowing of SNCV and MNCV, was found in the untreated diabetic rats 4 weeks after STZ injection. At a dose of 0.5 mg/kg/day or more fidarestat showed significant effects on these nervous dysfunctions, effects that were more potent than those shown by the other inhibitors. Furthermore, following the 2-week administration of fidarestat (1 mg/kg/day), epalrestat (48 mg/kg/day) or zenarestat (20 mg/kg/day), which began 2 weeks after STZ injection, sorbitol content in the sciatic nerve, produced by AR, a rate-limiting enzyme in the polyol pathway, was determined at 3, 8, 12, and 24 h after final administration. At each point in time, sorbitol content in the untreated diabetic rats was much higher than that in the normal control rats. Fidarestat suppressed sorbitol accumulation remarkably and continuously until 24 h after administration. On the other hand, the inhibitory effect by zenarestat declined in a time-dependent manner, and epalrestat did not decrease sorbitol content. Therefore, these results suggest that continuous inhibition of increased polyol pathway flux can improve diabetic neuropathy more potently.

Marked suppression of T cells by a benzothiophene derivative in patients with human T-lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis

In a search for new anti-autoimmune agents that selectively suppress activation of autoreactive T cells, one such agent, 5-methyl-3-(1-methylethoxy)benzo[b]thiophene-2-carboxamide (CI-959-A), was found to be effective. This compound, which is known to suppress tumor necrosis factor alpha (TNF-alpha)-induced CD54 expression, inhibited the primary proliferative response of the T cell to antigen (Ag)-presenting cells (APCs) including allogenic dendritic cells (DCs), autologous Epstein-Barr virus-infected B cells, and human T lymphotropic virus type I (HTLV-I)-infected T cells. Autoreactive T cells from patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) spontaneously proliferate in vitro, and their activation is reported to be associated with CD54 expression. The spontaneous proliferation of T cells from patients with HAM/TSP was entirely blocked by CI-959-A. However, in this study, the T-cell proliferation in 15 patients with HAM/TSP was found to depend more extensively on major histocompatibility complex (MHC) class II and CD86 than on CD54 Ags. Since most important APCs for the development of HAM/TSP are DCs and HTLV-I-infected T cells, the effect of CI-959-A on DC generation and on the expression of surface molecules on activated T cells is examined. CI-959-A suppressed recombinant granulocyte-macrophage colony stimulating factor (GM-CSF)- and recombinant interleukin-4-dependent differentiation of DCs from monocytes and inhibited the expression of CD54 and, more extensively, MHC class II and CD86 Ags. CI-959-A showed little toxicity toward lymphoma or HTLV-I-infected T-cell lines or toward monocytes and cultured DCs. These results suggest that CI-959-A might be a potent anti-HAM/TSP agent.

Soluble CD44 variant 6 as a prognostic indicator in patients with colorectal cancer

The expression of CD44v6 is well known as a useful marker of tumor progression and prognosis in colorectal cancer. In this study, we evaluated the serum levels of soluble CD44 splice variants containing exon v6 (sCD44v6) and examined the histological expression of CD44v6 in patients with colorectal cancer. Serum samples were obtained from 44 primary colorectal cancer patients before surgery. We used enzyme-linked immunosorbent assay to determine the serum levels of sCD44v6. The expression of CD44v6 was examined by immunohistochemical staining of the primary tumors obtained from the same patients. Both the serum concentration of sCD44v6 and the expression of CD44v6 were significantly associated with lymph node metastasis (p < 0.05). Furthermore, the serum level of sCD44v6 was higher in those patients with CD44v6-positive tumor tissues (154.4 +/- 34.8 ng/ml) than in those with CD44v6-negative ones (130.7 +/- 32.3 ng/ml; p < 0.05). The 5-year survival rate was significantly lower in patients with high serum levels of sCD44v6 (52.4%) than in those with low levels of sCD44v6 (78.0%; p < 0.05), and it was also significantly lower in patients with CD44v6-positive cancer (42.1%) than in those with CD44v6-negative cancer (84%; p < 0. 01). We concluded that preoperative elevation in the serum levels of sCD44v6 might be a prognostic indicator for patients with colorectal cancer.

[Gene cloning and expression of Mycobacterium leprae alpha 2 antigen]

OBJECTIVES

The recombinant alpha 2 antigen of M. leprae was prepared using the molecular biologic tools and the recombinant DNA expression technology.

METHODS

Screening of the M. leprae expression library was performed by the plaque hybridization technique. Nucleotide sequences were determined by dideoxy termination method.

RESULTS

The gene coding for alpha 2 antigen of M. leprae was cloned and characterized, and the complete nucleotide sequence data has been assigned in the GSDB, DDBJ, EMBL and NCBI nucleotide sequence databank. The over expression system of alpha 2 antigen gene in E. coli was constructed, and the recombinant alpha 2 antigen has been purified by amylose column chromatography at the purity of more than 95%. More than 10 mg of recombinant alpha 2 antigen has been obtained from 200 ml of liquid culture.

CONCLUSION

The recombinant alpha 2 antigen of M. leprae could be used as one of the specific antigens for the sero-diagnosis of leprosy.

Glucose transporter 2 concentrations in hyper- and hypothyroid rat livers

The deterioration of glucose metabolism frequently observed in hyperthyroidism may be due in part to increased gluconeogenesis in the liver and glucose efflux through hepatocyte plasma membranes. Glucose transporter 2 (GLUT 2), a facilitative glucose transporter localized to the liver and pancreas, may play a role in this distorted glucose metabolism. We examined changes in the levels of GLUT 2 in livers from rats with l-thyroxine-induced hyperthyroidism or methimazole-induced hypothyroidism by using Western blotting to detect GLUT 2. An oral glucose tolerance test revealed an oxyhyperglycemic curve (impaired glucose tolerance) in hyperthyroid rats (n=7) and a flattened curve in hypothyroid rats (n=7). GLUT 2 levels in hepatocyte plasma membranes were significantly increased in hyperthyroid rats and were not decreased in hypothyroid rats compared with euthyroid rats. The same results were obtained with a densitometric assay. These findings suggest that changes in the liver GLUT 2 concentration may contribute to abnormal glucose metabolism in thyroid disorders.

CD40-deficient mice infected with the defective murine leukemia virus LP-BM5def do not develop murine AIDS but produce IgE and IgG1 in vivo

CD40-deficient mice, when inoculated with the LP-BM5def murine retorvirus, become infected and show virus expression similar to wild-type mice. However, unlike the wild-type mice, CD40-deficient mice do not develop symptoms of immunodeficiency, lymphoproliferative disease and the typical histological changes in the lymphoid tissue. These results show that the CD40-CD40 ligand (CD40L) interaction in vivo is essential for anergy induction and the subsequent development of immunodeficiency and pathologic expansion of lymphocytes. Infected CD40-deficient mice and their littermates express a similar pattern of cytokine mRNA, which is not biased towards a Th2 phenotype. Nevertheless, hypergammaglobulinemia is induced in infected wild-type and CD40-deficient mice. Surprisingly, murine AIDS infection even induces IgE production in CD40-deficient mice in vivo. Our data demonstrate that antibody class switch to IgE and IgG1 can be induced by a retroviral infection in vivo even in the absence of CD40-CD40L interaction and an apparent switch to a Th2 cytokine production.

[A case of medial medullary syndrome detected by diffusion-weighted magnetic resonance imaging]

We report an 84-year-old woman with medial medullary syndrome diagnosed by diffusion-weighted magnetic resonance imaging (MRI). She was admitted because of left hemiparesis and hypesthesia. T2-weighted and diffusion-weighted MRI showed a high signal lesion at the right medial medulla oblongata 10 days after the onset. It is well known that diffusion-weighted MRI is useful for detecting supratentrial cerebral ischemic lesions in the extremely acute stage. However, to our knowledge, there have been only a few reports of diffusion-weighted MRI in patients with ischemic stroke of the medulla oblongata. Normal nerve fibers in the direction perpendicular to the motion-probing gradient (MPG) shows a high signal by diffusion-weighted MRI (anisotropy of apparent diffusion cofficient [ADC]). Normal nerve fibers in the pyramidal tract of medulla oblongata also shows a high signal when the MPG pulse is applied in the x and y directions. We solved this problem by using isotropic diffusion-weighted imaging and were able to detect ischemic lesion of medial medullary infarction in the acute phase.

S-phase accumulation precedes apoptosis induced by preoperative treatment with 5-fluorouracil in human colorectal carcinoma cells

BACKGROUND

In this study, the authors examined the correlations among enhancement of apoptosis, changes in cell cycle distribution, and expression of Ki-67 in human colorectal carcinoma cells during different durations of preoperative treatment with 5-fluorouracil (5-FU).

METHODS

Forty-one patients with advanced colorectal carcinoma were divided into 4 groups, which received intravenous 5-FU at 500 mg/body/day preoperatively for 3 days (n = 11), 5 days (n = 13), 7 days (n = 9), or 10 days (n = 8). Patients were further divided into two subgroups according to the DNA ploidy pattern of their tumors, i.e., diploid or aneuploid. Apoptotic cells were stained by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method. The expression of Ki-67 was examined by immunohistochemical staining. Flow cytometry was used to analyze changes in cell cycle distribution.

RESULTS

Apoptosis of cancer cells was mostly increased in the 7-day group (apoptotic index [Al]: 18.3+/-1.7%] compared with that of the 3-day, 5-day (AI: 11.3+/-2.3% and 13.2+/-2.8%, respectively) (P < 0.01), or 10-day (Al: 16.2+/-2.1%) (P < 0.05) groups. The expression of Ki-67 was reduced with increasing prolongation of 5-FU administration, from 55.2+/-2.1% in the 3-day group to 38.1+/-2.7% in the 10-day group. The authors also assessed the S-phase fraction (SPF) of cancer cells to evaluate changes in cell cycle distribution caused by 5-FU. All tumor samples from patients treated by 5-FU showed S-phase accumulation. The ratio of SPF (after 5-FU/before 5-FU) was higher in the 5-day group (2.35+/-0.78) than in the 3-day (1.71+/-0.48), 7-day (1.68+/-0.55), or 10-day (1.20+/-0.20) groups (P < 0.05). DNA ploidy pattern of the tumor had no influence on the enhancement of apoptosis, the increased ratio of SPF, or the decrease in proliferative activity of colorectal carcinoma cells induced by 5-FU.

CONCLUSIONS

S-phase accumulation preceded apoptotic cell death when intravenous 5-FU was administered continuously to human colorectal carcinoma cells.

Clinical application of magnetoencephalography in a patient with corticobasal degeneration

Previous neuroimaging studies in corticobasal degeneration (CBD), such as MRI and positron emission tomography, showed lateralized cortical atrophy and a decrease in cortical oxygen metabolism, respectively. The advantage of magnetoencephalography in the research of the auditory system is that activity of both hemispheres can be detected separately. Auditory-evoked magnetic fields (AEFs) were then applied to a patient with corticobasal degeneration. The strength of N100m equivalent current dipoles (ECD) in left hemisphere was extremely smaller (20 nAm) than that in right hemisphere (48 nAm). This results implies that CBD patient might have a decrease in the number of neurons in the primary auditory cortex. This study suggests that AEF measurement is one of the most powerful tools for detecting latent impairment of auditory function in patients with corticobasal degeneration.

[Spinal subarachnoid hemorrhage presenting as disturbance of consciousness with severe hypoglycorrhachia]

We report the case of an 84-year-old woman with spinal subarachnoid hemorrhage who presented with disturbance of consciousness and nuchal stiffness, bloody cerebrospinal fluid and severe hypoglycorrhachia. Initially, it was difficult to determine whether this was a case of spinal subarachnoid hemorrhage, purulent meningitis, or hemorrhagic encephalitis, because of the nuchal stiffness, disturbance of consciousness and severe hypoglycorrhachia. It is known that intracranial subarachnoid hemorrhage is accompanied by mild hypoglycorrhachia, but descriptions of glucose levels in cerebrospinal fluid in cases of spinal subarachnoid hemorrhage are rare. This case suggests that both spinal subarachnoid hemorrhage and intracranial subarachnoid hemorrhage are associated with hypoglycorrhachia. Furthermore, spinal subarachnoid hemorrhage is frequently accompanied by disturbance of consciousness. Therefore, sudden back pain or lumbago might not be interpreted as indicators of spinal subarachnoid hemorrhage, because patients, particularly elderly patients, may lose consciousness. We emphasize that the possibility of spinal subarachnoid hemorrhage should be considered in patients with disturbance of consciousness or hypoglycorrhachia even if they do not complain of sudden back pain.

Etiology of idiopathic scoliosis. Computational study

A review of the literature on the mechanical aspects of the etiology for idiopathic scoliosis reveals that the buckling hypothesis has been presented as a purely mechanical phenomenon. In an attempt to confirm the buckling hypothesis, a numerical simulation of growth and the resulting buckling phenomena was done by means of finite element analysis. It previously was observed that growth was induced in the T4 to T10 vertebrae. Only the sacrum was assumed to be stationary. From the growth analysis, a deformation process that mitigated thoracic kyphosis was obtained as observed in healthy children during early adolescence. From the buckling analysis, the first to the fourth buckling modes that correspond to the first side bending, first forward bending, first rotation, and second side bending modes were obtained. The shape of the fourth buckling mode (second side bending mode) was in good agreement with the clinical shape. Considering the potential for controlling these modes by posture change, it is concluded that the second bending mode in the coronal plane is one of the most likely etiologic candidates in the mechanics of thoracic idiopathic scoliosis.

Effects of thyroid hormone on the sorbitol pathway in streptozotocin-induced diabetic rats

Sorbitol accumulation plays an important role in diabetic complications involving the kidney, nerves, retina, lens and cardiac muscle. To investigate the influence of thyroid hormone on the sorbitol pathway, we studied the effects of thyroid hormone on polyol metabolism in normal and diabetic rats. Rats were divided into three groups: controls, streptozotocin (STZ)-induced diabetic euthyroid rats (DM) and STZ-induced diabetic hyperthyroid (thyroxine-injected) rats (DM+HT). The sorbitol (Sor) concentrations in the kidney, liver and sciatic nerve (2.53+/-0.74, 0.97+/-0.16 and 24.0+/-5.1 nmol/mg protein, respectively) of the DM rats were significantly higher than those (1.48+/-0.31, 0.58+/-0.13 and 3. 1+/-0.6 nmol/mg protein) of the control rats. The Sor concentrations in the kidney and sciatic nerve of the DM+HT rats (1.26+/-0.29 and 9. 40+/-1.2 nmol/mg protein) were significantly lower than those in the DM rats. These values were reduced in the liver, unchanged in the kidney, and increased in the sciatic nerve from the hyperthyroid rats without diabetes. Thyroid hormone reduced the aldose reductase (AR) activities in the kidney, liver and sciatic nerve of the DM rats, and similarly reduced AR in the kidney and liver, but not in the sciatic nerve, of the non-diabetic rats. The sorbitol dehydrogenase (SDH) activities were decreased by thyroid hormone in the kidney and liver but not the sciatic nerve of DM rats. In the non-diabetic rats, this enzyme activity was decreased in liver, but not in kidney or sciatic nerve. A positive correlation between the Sor concentration and AR activity was observed in the kidney and liver but not in the sciatic nerve from control, DM and DM+HT rats. A negative correlation was observed between the Sor concentration and SDH activities in the same organs. These data suggest that thyroid hormone affects the sorbitol pathway, but the detailed mechanism whereby this hormone reduces the sorbitol content (especially in diabetic rats) remains to be clarified.

Propentofylline inhibits production of TNFalpha and infection of LP-BM5 murine leukemia virus in glial cells

We examined the effects of a xanthine derivative, propentofylline, on TNFalpha production by glial cells and on infection ofglial cells with a murine leukemia virus, LP-BM5, which induces murine AIDS in susceptible mice. Propentofylline suppressed TNFalpha production in glial cells and also effectively suppressed infection ofglial cells with LP-BM5 in vitro. Addition ofTNFalpha, but not IL-1 or IL-6, abolished the suppressive effects ofpropentofylline. Anti-TNFalpha antibody also suppressed infection of LP-BM5 in these cells. These findings suggest that propentofylline suppressed LP-BM5 infection in glial cells by suppressing TNFalpha production by these cells. Because propentofylline reportedly passes through the blood-brain barrier, it may be useful in the treatment of central nervous system involvement by HIV infection or neurological diseases in which TNFalpha plays a causative role, such as multiple sclerosis.

The contributions of reactive oxygen intermediates and reactive nitrogen intermediates to listericidal mechanisms differ in macrophages activated pre- and postinfection

The contribution of reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI) to the killing of Listeria monocytogenes by macrophages activated by addition of spleen cells from listeria-immune mice plus specific antigen was examined. When macrophages were infected with L. monocytogenes and then spleen cells were added, there was not as big a difference in listericidal activity between macrophages cultured with normal spleen cells and those cultured with immune spleen cells as expected. In this culture system, RNI was mainly involved in the macrophage intracellular killing. In macrophages first activated and then infected, a significant level of enhanced killing was observed. Blockade of ROI production drastically affected the enhanced killing ability, while inhibition of RNI production had a negligible effect. Thus, the contributions of ROI and RNI to listericidal mechanisms of macrophages were different between macrophages activated at pre- and postinfection stages.

Enhancement of immobility in mouse forced swimming test by treatment with human interferon

We investigated the depression induced by human interferons using the forced swimming test in mice. Intravenous (i.v.) administration of interferon-alpha s (natural interferon-alpha, recombinant interferon-alpha-2a and recombinant interferon-alpha-2b, 600-60000 IU/kg) increased the immobility time in the forced swimming test in a dose-dependent manner, but natural interferon-beta and recombinant interferon-gamma-1a did not affect the immobility time. The increase in the immobility time induced by recombinant interferon-alpha-2b peaked at 15 min after dosing. Administration of recombinant interferon-alpha-2b (6000 IU/kg, i.v.) once daily for 7 consecutive days increased the immobility time, but natural interferon-beta and recombinant interferon-gamma-la did not. Recombinant interferon-alpha-2b in combination with the anti-depressants imipramine (10 mg/kg, i.p.) and mianserin (20 mg/kg, i.p.) did not increase the immobility time. These results suggest that interferon-alpha has a greater potential for inducing depression than interferon-beta and -gamma, and that anti-depressants are effective against interferon-alpha-induced depression.

Reduction of activity, but no decrease in concentration, of erythrocyte Cu,Zn-superoxide dismutase by hyperglycaemia in diabetic patients

Cu,Zn-superoxide dismutase(SOD) activity in erythrocytes is affected by various diseases, including diabetes mellitus (DM). We investigated changes in the Cu,Zn-SOD activity compared to changes in the Cu,Zn-SOD concentration in erythrocytes obtained from patients with Type 2 (non-insulin-dependent) diabetes mellitus. Cu,Zn-SOD activity in erythrocytes was significantly lower in Type 2 DM patients than in healthy non-diabetic subjects. The activity correlated negatively with HbA1c, but not with other indicators of metabolic control, such as fasting blood glucose or plasma cholesterol or triglyceride. However, there was no statistically significant difference in erythrocyte concentration of Cu,Zn-SOD between diabetic and control samples. Concentration did not correlate with enzymatic activity or HbA1c. These findings indicate that the inactivation of Cu,Zn-SOD activity in erythrocytes of Type 2 DM patients by hyperglycaemia may be slow, because there is a negative correlation between the enzyme activities and HbA1c levels, but not fasting blood glucose levels. This is consistent with glycosylation of the active site of Cu,Zn-SOD, without any effect of hyperglycaemia on the concentration of Cu,Zn-SOD.

Delayed healing of chronic gastric ulcer after Helicobacter pylori infection in mice

It has been suggested that there is a close relationship between Helicobacter pylori and the onset or recurrence of gastroduodenal disease. The aim of this study was to examine the effect of H. pylori on the healing of chronic gastric ulcers induced in mice. H. pylori administered to nude mice delayed the healing of experimental acetic acid-induced gastric ulcers. Histological examination showed the occurrence of high densities of H. pylori on the surface of epithelial cells and in the ulcerated area. Repeated administration of amoxicillin (10 mgkg(-1) daily for 5 days) eradicated H. pylori and increased the rate of healing of gastric ulcers in H. pylori-infected mice, but metronidazole, which also eradicated the organisms, did not significantly affect the rate of healing. In conclusion, H. pylori-infection delayed the healing of gastric ulcers induced by the serosal application of acetic acid in mice, possibly by aggravation or prolongation of the mucosal inflammation. Amoxicillin eradicated H. pylori and promoted gastric ulcer healing in mice infected with H. pylori.

Surface expression and release of soluble forms of CD8 and CD23 in CD40- and IL-4-activated mononuclear cells from patients with Graves' disease (GD)

We investigated the effect of T cell-dependent B cell activation on the surface expression and release of the soluble forms of CD8 and CD23 by peripheral blood mononuclear cells (PBMC) obtained from patients with GD, versus patients with Hashimoto's thyroiditis, and normal controls. Incubating the PBMC with anti-CD40 MoAbs and IL-4 increased the soluble CD23 levels in cells from all three groups. An increase in the number of CD23+ cells was observed in the PBMC from the patients with GD, but not in PBMC from Hashimoto's thyroiditis or controls. Less soluble CD8 was released from anti-CD40 antibody and IL-4-stimulated PBMC obtained from patients with GD relative to those from the controls. In addition, the number of CD8+ cells was significantly reduced in stimulated PBMC from the GD patients relative to those from controls. Incubation of PBMC with anti-CD40 antibody plus IL-4 did not affect the proportions of CD4+, CD20+, Fas+ CD4+, and Fas+ CD8+ cells. The addition of T3 to cultured PBMC from controls did not reproduce the changes in CD23+ and CD8+ cells noted in the samples froin GD patients. Thus, T cell-dependent B cell activation, mediated by a CD40 pathway, may reduce the number of CD8+ cells, causing exacerbation of GD.

Prevention of murine AIDS development by (R)-9-(2-phosphonylmethoxypropyl)adenine

LP-BM5 murine leukemia virus (MuLV) infection causes severe immunodeficiency termed murine AIDS (MAIDS). The acyclic nucleoside phosphonates, (R)-9-(2-phosphonylmethoxypropyl)adenine (PMPA) and 9-(2-phosphonylmethoxyethyl)adenine (PMEA) were examined, in comparison with zidovudine (AZT), for their inhibitory effect on the development of MAIDS. Although no significant difference in inhibition of LP-BM5 MuLV replication was identified between PMPA and PMEA in cell cultures, PMPA was obviously less cytotoxic to the host lymphocytes. None of the mice treated in vivo with 5 or 25 mg/kg of PMPA or 25 mg/kg of PMEA developed MAIDS at 5 weeks after viral infection. However at 9 weeks, none of the 25 mg/kg PMPA-treated mice progressed to MAIDS, except for one that developed mild MAIDS, whereas PMEA, even at 100 mg/kg, could not prevent disease progression. MAIDS-associated activation of lymphocytes and viral replication were drastically inhibited by PMPA treatment. These results indicate that PMPA is a highly effective antiretroviral agent in vivo.

[Effect of plaunotol on trinitrobenzene sulfonic acid and acetic acid induced colonic lesions in rats]

The aim of this study was to assess the effect of plaunotol, an anti-ulcer agent, on trinitrobenzene sulfonic acid (TNB)- and acetic acid-induced colonic lesions in rats. Plaunotol significantly reduced the severity of colonic mucosal lesions induced by TNB at a dose of 600 mg/kg/day. Moreover, plaunotol, at a dose of 600 mg/kg/day, significantly depressed the myeloperoxidase activity of the lesioned area induced by TNB of the rat colon. In the model of colitis induced by acetic acid, plaunotol reduced the area of lesions dose-dependently and significantly at doses of 60, 200 and 600 mg/kg/day as assessed by macroscopic observation. Microscopic observation showed obvious changes by administration of plaunotol such as reduction of epithelial cell necrosis, decreased mucin production and a decreased infiltration of a large number of neutrophils. In conclusion, plaunotol showed a protective effect against colonic lesion formation induced by TNB and acetic acid in rats. This study suggests the possibility that plaunotol may be effective and useful for treatment of inflammatory bowel disease in humans.

[Prevalence of dementia and its subtypes in a rural area in Japan]

The prevalence of dementia in Japan in 1985 for people aged 65 years or older was 4.8%. Vascular dementia (VD) has been reported to be the commonest subtype A report from Tokyo in 1970 showed that it was 2.8 times more frequent than Alzheimer type dementia (SDAT). We assessed the prevalence of dementia in a rural area (population: 12,931, 25.3% were 65 years or older in 1994) in Kyoko. First, we questioned subjects about their demographic circumstances, memory disturbance, apraxia (agnosia) and daily activities. Our questionnaire was answered by 3.132 (95.8%) subjects, and 2,280 of them agreed to be examined by neurologists. Those who met the appropriate criteria of the DSM-III-R and NINCDS-ADRDA were diagnosed with dementia. By use of the Hachinski ischemic score (HIS), we distinguished VD from non-vascular dementia. In this study patients with non-vascular dementia were diagnosed with SDAT by the neurologists. Analysis of the data revealed that 4.8% of the study population was demented. According to the HIS results, only 3 of 15 had vascular dementia. The prevalence of dementia was the same as the average prevalence in Japan even though the elderly population of this town was twice as high as the average. It is hard to determine the prevalence of dementia in any community. Many factors must be taken into consideration: the coverage rate, the criteria for dementia, and whether to include institutionalized residents. The prevalence of dementia will increase with the aging of the population, and we must collect accurate data in order to plan efficiently.

[The trend of leprosy treatment in which the prevention of peripheral nerve damage being as its main theme]

We have examined in leprosy in Bangladesh the change in the rate of peripheral nerve damage before and after the treatment. In the well-organized NGO program where the early diagnose is given, the damage rate improves slightly during the treatment. But among the MB cases, it has been found that the damage rate taken at the time of patient's first check-up still stays high. Furthermore, during the treatment of MB cases, 72% cases show the episode of neuritis, and even during two years of observation period after treatment, 15% cases show the same episode. Among the recurrent cases of last ten years in Oku-Komyo-en, we have looked into the ways of drugs prescribed for the treatment of previous recurrent term in the double recurrent cases. In these prescription, the amount of each dosage was relatively a little and the prescription period was rather long. In RFP, prescription frequency was relatively high, and in DDS and CLF, they were low. We think that the treatment of leprosy in Japan should be based on WHO's regimen. However before making Japanese regimen, it is necessary to discuss more when to finish the treatment.

[A case of juvenile muscular atrophy of the upper limb with intraspinal cavity formation]

The patient was a 23-year-old man. He had no history of trauma in the head and neck. When he was 20 years old (in 1992), he noticed muscle atrophy and weakness in the right hand. In a hospital, he had cervical MRI study and other examinations. The diagnosis was juvenile muscular atrophy of the upper limb (Hirayama's disease). After that the symptoms became worse in the bilateral forearms and hands. The neurological examination showed severe atrophy in bilateral C7 to Th1 innervated muscles, right pyramidal sign, mild superficial and deep sensory disturbance in the dermatome of C7-Th1, and right Horner's sign. Cervical MRI and myelography revealed the atrophy of cervical cord and intraspinal cavity formations from C5 to Th1. We concluded that chronic and intermittent compression to cervical cord with flexion position made the cavities during the clinical course because these cavities were not found in the MRI taken in 1992.

Inhibition of human immunodeficiency virus type 1 replication and cytokine production by fluoroquinoline derivatives

We have recently identified 8-difluoromethoxy-1-ethyl-6-fluoro-1, 4-dihydro-7-[4-(2-methoxyphenyl)-1-piperazinyl]-4-oxoquinoline-3-carb oxylic acid (K-12) as a potent and selective inhibitor of human immunodeficiency virus type 1 (HIV-1) transcription. In the search for more effective derivatives and their mode of action, we have found 7-(3,4-dehydro-4-phenyl-1-piperidinyl)-1, 4-dihydro-6-fluoro-1-methyl-8-trifluoromethyl-4-oxoquinoline-3- carboxylic acid (K-37) and 8-difluoromethoxy-1,4-dihydro-6-fluoro-7-(3, 4-dehydro-4-phenyl-1-piperidinyl)1-[4,(1,2, 4-triazol-1-yl)methylphenyl]-4-oxoquinoline-3-carboxylic acid (K-38) to be more potent inhibitors of HIV-1 replication than K-12. The EC50 values of K-37 and K-38 for HIV-1IIIB were 27 and 3.8 nM in peripheral blood mononuclear cells, respectively. These values were approximately 3- and 24-fold lower than the EC50 of K-12. K-38 was also a more potent inhibitor of HIV-1 replication in chronically infected cells, such as tumor necrosis factor alpha-stimulated OM-10. 1 cells. K-37 and K-38 proved to be more cytotoxic than K-12 for a variety of cell lines as well as peripheral blood mononuclear cells. These compounds were more inhibitory of Tat-induced HIV-1 long terminal repeat-driven gene expression than K-12, which suggests that their mechanism of action is attributable in part to the inhibition of Tat function. Interestingly, K-37 and K-38 could suppress the production of tumor necrosis factor alpha and interleukin 6 in phytohemagglutinin-stimulated peripheral blood mononuclear cells and the expression of intercellular adhesion molecule 1 in tumor necrosis factor alpha-stimulated human umbilical vein endothelial cells at their nontoxic concentrations. In contrast, another K-12 derivative, 1, 4-dihydro-8-dimethylaminomethyl-6-fluoro-7-[4-(2-methoxyphenyl)-1-pip eradinyl]-1-methyl-4-oxoquinoline-3-carboxylic acid (K-42), had anti-HIV-1 activity and cytotoxicity profiles similar to those of K-12, but K-42 scarcely inhibited the cytokine production and intercellular adhesion molecule 1 expression.