Effects of 15-month aldose reductase inhibition with fidarestat on the experimental diabetic neuropathy in rats

We examined the effects of long-term treatment with an aldose reductase inhibitor (ARI) fidarestat on functional, morphological and metabolic changes in the peripheral nerve of 15-month diabetic rats induced by streptozotocin (STZ). Slowed F-wave, motor nerve and sensory nerve conduction velocities were corrected dose-dependently in fidarestat-treated diabetic rats. Morphometric analysis of myelinated fibers demonstrated that frequencies of abnormal fibers such as paranodal demyelination and axonal degeneration were reduced to the extent of normal levels by fidarestat-treatment. Axonal atrophy, distorted axon circularity and reduction of myelin sheath thickness were also inhibited. These effects were associated with normalization of increased levels of sorbitol and fructose and decreased level of myo-inositol in the peripheral nerve by fidarestat. Thus, the results demonstrated that long-term treatment with fidarestat substantially inhibited the functional and structural progression of diabetic neuropathy with inhibition of increased polyol pathway flux in diabetic rats.

Prognostic significance of reverse transcriptase-polymerase chain reaction measurement of carcinoembryonic antigen mRNA levels in tumor drainage blood and peripheral blood of patients with colorectal carcinoma

BACKGROUND

The objective of this study was to assess the prognostic value of detecting circulating tumor cells in the tumor drainage blood and peripheral blood of patients with colorectal carcinoma.

METHODS

A total of 53 patients with advanced colorectal carcinoma were studied. Tumor drainage blood and peripheral blood samples that were obtained during surgery were examined for carcinoembryonic antigen (CEA) mRNA using reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

In spiking experiments, the assay indicated a sensitivity limit of 1 carcinoma cell per 10(6) cells. CEA mRNA was detected in the tumor drainage blood of 36 of 53 patients (68%) and in the peripheral blood of 18 of 53 patients (34%). The rate of detection in both tumor drainage blood and peripheral blood was significantly higher in patients with lymph node metastasis, lymphatic invasion, or vascular invasion (P < 0.05). Among those patients who underwent potentially curative resection, the 2-year disease free survival rate of patients whose tumor drainage or peripheral blood was negative for CEA mRNA was significantly better than that of patients who showed CEA mRNA positivity of either sample (tumor drainage blood: 100% vs. 57%; P < 0.05; peripheral blood: 74% vs. 50%; P < 0.01), although the follow-up thus far has been only 9-30 months.

CONCLUSIONS

The presence of CEA mRNA in the blood is a useful indicator of circulating tumor cells, and it is one of the determinant prognostic factors for patients with colorectal carcinoma. Moreover, the absence of CEA mRNA in tumor drainage blood was found to be a superior marker for disease free survival compared with that in peripheral blood.

Telomerase activity and p53 gene mutation in familial polyposis coli

BACKGROUND

Familial adenomatous polyposis (FAP) is a dominantly inherited disorder and it is difficult to know when polyps change to carcinoma. In this study, we retrospectively evaluated whether telomerase activity and p53 gene mutations are useful parameters for detecting malignant changes in polyps in patients with FAP.

MATERIALS AND METHODS

Twenty-one tissue samples (carcinoma: 5, large polyp: 8, and small polyp: 8) were obtained from 8 patients with FAP. Colorectal carcinomas were detected in 5 patients. As a control, 68 colorectal carcinomas and 11 adenomatous polyps with synchronous colorectal carcinoma from 68 patients and 8 polyps from 8 patients without colorectal carcinoma were obtained. The telomeric repeat amplification protocol (TRAP) assay was used for the detection of telomerase activity. In 21 samples from FAP patients, mutations of exon 5 to 8 in the p53 gene were analyzed by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method.

RESULTS

In 5 patients with FAP who had carcinomas in their colon and rectum, all the samples (carcinomas, large polyps and small polyps) showed telomerase activity. In contrast, in the 3 patients with FAP who had no carcinomas, telomerase activity was not detected in either the large or small polyps. Telomerase activity was detected in 51 out of 68 control colorectal carcinomas (75%) and in 6 out of 19 adenomas (32%). The p53 gene mutation was detected in only 2 carcinomas from 2 patients with FAP and was not detected in any large and small polyps.

CONCLUSION

These findings suggest that telomerase is activated before the occurrence of the p53 gene mutation. In FAP, genetic changes associated with the development of colonic adenoma into carcinoma might activate telomerase and such genetic changes might occur in whole polyps of the colon and rectum.

Production of functionally deficient dendritic cells from HTLV-I-infected monocytes: implications for the dendritic cell defect in adult T cell leukemia

Adult T cell leukemia (ATL) is induced by an infection with human T lymphotropic virus type I (HTLV-I) and is accompanied by immunodeficiency. Monocyte-derived immature dendritic cells (DCs) donated by 11 ATL patients were suppressed in the ability to take up fluorescein isothiocyanate (FITC)-dextran and were down-regulated in the expression of CD1a and CD86 antigens (Ags). Monocytes from the patients showed impaired expression of CD14 and HLA-DR Ags. These results suggest intrinsic abnormalities of monocytes and a defect of DC maturation in ATL patients. Therefore, we examined the influence of HTLV-I infection of monocytes on their differentiation to DCs. Monocytes obtained from healthy donors were susceptible to HTLV-I infection in vitro. HTLV-I-infected monocytes were down-regulated in the expression of CD14 Ags, and immature DCs obtained from them expressed CD1a poorly and were impaired in the ability to take up FITC-dextran. Mature DCs differentiated from these cells could not stimulate autologous CD4(+) T cell or CD8(+) T cell proliferation, even after being secondarily pulsed with HTLV-I at an immature DC stage. These results suggest that HTLV-I-infected monocytes cannot properly differentiate to DCs and that this might be one of the important mechanisms producing dysfunctional DCs in ATL patients.

Reduced E-cadherin expression and enlargement of cancer nuclei strongly correlate with hematogenic metastasis in colorectal adenocarcinoma

BACKGROUND

Synchronous and metachronous hematogenic metastases are frequently detected in patients with colorectal carcinoma. Once these metastases have developed, the prognoses of patients are poor. Previously, we reported that enlargement of cancer nuclei significantly correlated with metastatic potential of gastric cancer and hepatocellular carcinoma. Moreover, recently it has been reported that reduced expression of E-cadherin is associated with tumor metastasis. To evaluate the correlation between nuclear area (NA) of cancer cells and expression of E-cadherin, and to elucidate whether these factors correlate with clinical outcome in patients with colorectal carcinoma, 105 consecutive patients were investigated.

METHODS

In each case, the NAs of 600 cancer nuclei were analyzed by means of a computer-assisted image analysis system and E-cadherin expression was detected immunohistochemically by an anti-E-cadherin monoclonal antibody. The expression levels of E-cadherin were divided into three groups according to the percentages of E-cadherin-positive cells (level 0: positive cells < or = 50%, level 1: 50% < positive cells < or = 80%, level 2: positive cells > 80%).

RESULTS

The mean NA of cancer cells in 105 tumors was 57 microm2. The NAs of cancer cells enlarged in proportion to the decrease of E-cadherin expression levels (level 0, n = 48, 62 microm2; level 1, n = 35, 57 microm2, level 2, n = 22, 46 microm2, P = 0.002). The 10-year survival rates decreased in proportion to the reduced E-cadherin expression levels (80% in level 2, 64% in level 1, and 42% in level 0, P = 0.004). Moreover, the 10-year survival rate of 54 patients with large NA tumors (< or = 54 microm2, 36%) was significantly poorer than that of 51 patients with small NA tumors (< 54 microm2, 80%, P < 0.001). The NA of cancer cells was recognized as an important predictor for prognosis and hematogenic metastasis. Although reduced E-cadherin expression was not recognized as the risk factor for hematogenic metastasis, 80% of patients who developed hematogenic metastasis had tumors with both enlarged cancer nuclei and reduced E-cadherin expression.

CONCLUSIONS

Detection of NA of cancer cells and E-cadherin expression in patients with colorectal carcinoma may reveal important information for hematogenic metastasis.

Involvement of central opioid systems in human interferon-alpha induced immobility in the mouse forced swimming test

1. We investigated the mechanism by which human interferon-alpha (IFN-alpha) increases the immobility time in a forced swimming test, an animal model of depression. 2. Central administration of IFN-alpha (0.05 - 50 IU per mouse, i.cist.) increased the immobility time in the forced swimming test in mice in a dose-dependent manner. 3. Neither IFN-beta nor -gamma possessed any effect under the same experimental conditions. 4. Pre-treatment with an opioid receptor antagonist, naloxone (1 mg kg(-1), s.c.) inhibited the prolonged immobility time induced by IFN-alpha (60 KIU kg(-1), i.v. or 50 IU per mouse. i.cist. ). 5. Peripheral administration of naloxone methiodide (1 mg kg(-1), s. c.), which does not pass the blood - brain barrier, failed to block the effect of IFN-alpha, while intracisternal administration of naloxone methiodide (1 nmol per mouse) completely blocked. 6. The effect of IFN-alpha was inhibited by a mu(1)-specific opioid receptor antagonist, naloxonazine (35 mg kg(-1), s.c.) and a mu(1)/mu(2) receptor antagonist, beta-FNA (40 mg kg(-1), s.c.). A selective delta-opioid receptor antagonist, naltrindole (3 mg kg(-1), s.c.) and a kappa-opioid receptor antagonist, nor-binaltorphimine (20 mg kg(-1), s.c.), both failed to inhibit the increasing effect of IFN-alpha. 7. These results suggest that the activator of the central opioid receptors of the mu(1)-subtype might be related to the prolonged immobility time of IFN-alpha, but delta and kappa-opioid receptors most likely are not involved.

Production of IL-10 and IL-12 in CD40 and interleukin 4-activated mononuclear cells from patients with Graves' disease

We investigated the effect of T cell-dependent B cell activation on the production of IL-10 and IL-12 by peripheral blood mononuclear cells (PBMCs) obtained from patients with Graves' disease vs Hashimoto's thyroiditis, type 1 diabetes or normal controls. Incubation of PBMCs, from each of the subject groups, with a combination of anti-CD40 monoclonal antibodies and interleukin 4 (IL-4)-activated B cells, as shown by an increased level of soluble CD23. There was also a notable increase in the number of CD23(+)cells in PBMCs from patients with Graves' disease as compared to the other subject groups. This combination of B cell stimulants increased production of IL-10 in PBMCs obtained from patients with Graves' disease relative to those patients with Hashimoto's thyroiditis, type 1 diabetes, or the control subjects. The production of IL-12 showed wide variation that depended on the basal IL-12 level. In subjects with a low basal IL-12 level there was a positive correlation between the production of IL-12 and that of IL-10 from PBMCs stimulated with anti-CD40 antibodies plus IL-4. On the contrary, in the patients with a high basal IL-12 level, no change or a decrease of IL-12 production was observed after the stimulation. Thus, T cell-dependent B cell activation via a CD40 pathway triggers the overproduction of IL-10 and overcome the effect of IL-12 to shift the Th(1)/Th(2)balance to Th(2)dominance in patients with Graves' disease but not in Hashimoto's thyroiditis or type 1 diabetes.

Identification of a major heparin and cell binding site in the LG4 module of the laminin alpha 5 chain

The G domain of the laminin alpha chains consists of five homologous G modules (LG1-5) and has been implicated in various biological functions. In this study, we identified an active site for cell and heparin binding within the laminin alpha5 G domain using recombinant proteins and synthetic peptides. Recombinant LG4, LG5, and LG4-5 modules were generated using a mammalian expression system. The LG4 and LG4-5 modules were highly active for cell binding, whereas the LG5 module alone showed only weak binding. Heparin inhibited cell binding to the LG4-5 module, whereas no inhibition was observed with EDTA or antibodies against the integrin beta(1) subunit. These results suggest that the LG4-5 module interacts with a cell surface receptor containing heparan sulfate but not with integrins. Solid-phase assays and surface plasmon resonance measurements demonstrated strong binding of the LG4 and LG4-5 modules to heparin with K(D) values in the nanomolar range, whereas a 16-fold lower value was determined for the LG5 module. Treatment with glycosidases demonstrated that N-linked carbohydrates on the LG5 module are complex-type oligosaccharides. The LG4-5 module, devoid of N-linked carbohydrates, exhibited similar binding kinetics toward heparin. Furthermore, cell binding was unaffected by removal of N-linked glycosylation. To localize active sites on the LG4 module, various synthetic peptides were used to compete with binding of the tandem module to heparin and cells. Peptide F4 (AGQWHRVSVRWG) inhibited binding, whereas a scrambled peptide of F4 failed to compete binding. Alanine replacements demonstrated that one arginine residue within F4 was important for cell and heparin binding. Our results suggest a critical role of the LG4 module for heparan sulfate-containing receptor binding within the laminin alpha5 chain.

[A study of institutional medical care of female victims of sexual assault and violence]

OBJECTIVE

The purpose of the study is to clarify the present situation of medical care for victims of sexual assault and violence. Medical facilities in two wards in Tokyo were studied in order to know what problems regarding medical care exist and how to support female victims.

METHODS

In April 1998, we distributed questionnaires to 338 medical facilities covering all the clinics and hospitals, that had more than only otorhinolaryngology and ophthalmology, in Kouto-ku and Sumida-ku, Tokyo. The questionnaire included questions about individual experience of consulting with sexual assault and violence against women, the number of victims in the last year, and their understandings for victims.

RESULT

1) 76 of the respondents completed the answer sheet by themselves. The mean age of the subjects was 57.4 years old, 16.3% of them had seen sexual assault victims, and about 36.8% had cared for victims of violence. 2) 67 victims of sexual assault and violence were reported in the previous year. 36% of victims of sexual assault were reported by facilities related to obstetrics, and 85% of victims of violence were reported by general medical facilities. 3) As for understandings for victims, those who thought the victims were responsible for the sexual assault also regarded violence as caused by carelessness of victims.

CONCLUSION

Medical facilities may be an important place to care for victims of sexual assault and violence against women. There are few data available as to how many women suffer from sexual violence. This study showed for the first time the reality of sexual assault and violence from the viewpoints of medical facilities in Japan, although it had some limitations. It is necessary for more discussion about roles of medical care for female victims of sexual assault and violence.

p53 as an indicator of lymph node metastases in invasive early colorectal cancer

We examined whether overexpression of p53 can be used as a new genetic marker to predict the presence of lymph node metastases of early invasive colorectal cancer. Forty-nine patients with primary colorectal adenocarcinomas invading to the submucosa (sm-CRC) were analyzed and 7 patients were found to have lymph node metastases. Immunostaining was used to detect the p53 overexpression; 43% of sm-CRC stained positive for p53 and all the cancer cells metastasized to lymph nodes were p53 positive. Both lymph node involvement and tumor budding were significantly more frequent in p53 positive than p53 negative tumors (p < 0.05, respectively), and multivariate analysis showed that p53 overexpression constituted a higher relative lisk for lymph node metastases of sm-CRC than either histologic type, level of sm invasion, macroscopic type, tumor budding or vascular invasion, although the difference was not significant (p = 0.086). We concluded that p53 overexpression is a useful biological marker of lymph node metastases of sm-CRC, and that p53 negative status may be an indicator for limited surgery, such as local excision of sm-CRC.

Vascularized metacarpal bone graft for scaphoid non-union and Kienböck's disease

A new vascularized bone graft from the base of the second metacarpal was used to treat scaphoid non-union and Kienböck's disease. In two patients with scaphoid non-union, the procedure promoted healing, even when the proximal segment was poorly vascularized. In one patient with Kienböck's disease, the graft held stable and wrist pain was markedly reduced. Further clinical experience may establish this procedure as an option for carpal bone fractures or disease.

Mitochondrial DNA mutations in Leigh syndrome and their phylogenetic implications

Of 100 patients with the clinical diagnosis of Leigh syndrome, 21 were found to have specific enzyme defects: 15 involving cytochrome c oxidase (COX); 4, pyruvate dehydrogenase complex (PDHC); one, complex I (reduced nicotinamide adenine dinucleotide [NADH]-coenzyme Q reductase) and one, complex II (succinate-ubiquinone reductase) deficiencies. In addition to the most common form of COX deficiency, mtDNA mutations in the adenosine triphosphatase (ATPase) 6 coding region were also commonly seen. Eighteen patients (18%) had mtDNA mutations at nucleotide position (np) 8993 or 9176. The mutated DNAs were present in a heteroplasmic state, comprising more than 90% of the DNA in muscle and/or blood samples from all patients. Patients with the T-to-G mutation at np 8993 usually had early onset of the disease with rapid progression, showing the typical clinical features of Leigh syndrome. On the other hand, those with the T-to-C 8993 mutation showed a milder and more chronic course. Patients with the mutation at np 9176 showed variable courses. Phylogenetic analysis of mtDNA D-loop sequences for the patients with the ATPase 6 mutations and normal Japanese subjects revealed that a T-to-G/C mutation at np 8993 and a T-to-C mutation at np 9176 occurred many times independently in the Japanese population.

[Worsened orthostatic hypotension due to levodopa administration in a case of Parkinson's disease]

A 70-year-old woman began to experience gait disturbance in 1995, followed by the appearance of action tremor of the left hand in 1996. This tremor was subsequently noted in the right hand. Her doctor initially diagnosed Parkinson's disease and administered amantadine and levodopa. The gait disturbance and tremor improved. However, she stopped taking the medication and her symptoms worsened in April, 1998. She was admitted to our hospital, and showed rigidity and action tremor predominantly on the left side, frozen gait, postural reflex disturbance and orthostatic hypotension. Following levodopa administration, her UPDRS score improved from 61.3 +/- 1.2 (mean +/- SD) to 41.7 +/- 5.4. However, she experienced a greater decrease in systolic blood pressure following administration upon standing, from 12.5 +/- 5.8 mmHg to 17.8 +/- 9.2 mmHg. Thus, although levodopa administration led to an improvement in rigidity, tremor and akinesia, her orthostatic hypotension worsened. Based on the present results clinicians should be aware of the potential of worsened orthostatic hypotension when prescribing levodopa to treat Parkinson's disease.

Human interferon-alpha induces immobility in the mouse forced swimming test: involvement of the opioid system

In a previous study, we indicated that human interferon (IFN)-alpha (IFN-alpha, 6 x 10(4) IU/kg, i.v.), but not human IFN-beta or -gamma, prolonged the immobility time of the forced swimming test in mice. In this study, we investigated the mechanism of the effect of human IFN-alpha. None of the mouse IFNs tested (IFN-alpha/beta, IFN-beta, and IFN-gamma, 3 x 10(5) U/kg, i.v.) changed the immobility time or the spontaneous locomotor activity in mice. Indomethacin (10 mg/kg, s.c.), a cyclooxygenase inhibitor, did not affect the increase in the immobility time induced by human IFN-alpha (6 x 10(4) IU/kg, i.v.). However, naloxone (1 mg/kg, s.c.), an opioid receptor antagonist, blocked the increasing caused by human IFN-alpha in the forced swimming test. These results suggest that the increase in the immobility time caused by human IFN-alpha in the forced swimming test might be mediated through opioid receptors, but not mouse IFN receptors.

Human interferon-alpha increases immobility in the forced swimming test in rats

OBJECTIVES

We examined the immobility of the forced swimming test induced in an animal model by human interferon (IFN), which has often been reported to induce depression in clinical use.

METHODS

In the present study, we examined the effects of human IFNs on results of the forced swimming test in rats.

RESULTS

Single intravenous (IV) administration of human IFN-alpha (6x10(4) IU/kg), but not of human IFN-beta or -gamma, significantly increased immobility time in the forced swimming test in rats. Repeated administration of human IFN-alpha (6x10(3) IU/kg) also significantly increased the immobility time. On the other hand, none of the rat IFNs (rat IFN-alpha, -beta and -gamma, 6x10(4) IU/kg, IV) changed the immobility time. Neither human IFNs nor rat IFNs changed the locomotor activity of rats.

CONCLUSIONS

These findings suggest that human IFN-alpha has a greater potential for inducing increase of the immobility in the rat forced swimming test than human IFN-beta and -gamma, and that the effect of human IFN-alpha might not be mediated through IFN-alpha/beta receptors.

Lipid peroxidation levels in rat cardiac muscle are affected by age and thyroid status

Free radicals, hydroxyperoxides and H(2)O(2) are all known to damage cell components. This study was designed to compare the concentrations of hydroxyperoxide and free radical scavengers in the cardiac muscles of old rats in the hyper- or hypothyroid condition, to determine whether rates of peroxidation would differ with age, thyroid status, or both. Rats were rendered hyper- or hypothyroid by administration of l-thyroxine or methimazole for 4 weeks. Among the old rats, the lipid peroxide (LPO) concentrations, measured as thiobarbituric acid (TBA) reactants, were significantly greater in the hyperthyroid than in the euthyroid state and the LPO concentrations measured as TBA+Fe(3+) reactants, which may be precursors of LPO, were significantly greater in the hyperthyroid state, whereas in young rats, the LPO concentrations measured by TBA or TBA+Fe(3+) methods did not differ significantly in the hyperthyroid state. In the euthyroid state, the concentration of LPO measured as TBA+Fe(3+) reactants was significantly reduced with age. Xanthine oxidase (XOD) activity also was markedly increased with age, being more pronounced in the hyperthyroid than in the euthyroid state. The Mn and Cu/Zn superoxide dismutase activities were greater in the hyperthyroid than in the euthyroid state. Glutathione peroxidase activity decreased with age in the euthyroid and, particularly, in the hyperthyroid state. Catalase activity was not affected in the old rats. Concentrations of alpha-tocopherol in the old rats were high in the hyperthyroid state and low in the hypothyroid state, whereas the levels of beta- and gamma-tocopherols in these rats were unchanged in both conditions as compared with the euthyroid state findings. Data suggest that the site of free radical generation differs in older rats, with additional shifts in the location of intracellular lipid peroxidation being noted during hyperthyroidism. Thus, as rats age, the reduction of the free radical scavenger system and the increase in LPO and XOD activities might induce myocardial dysfunction.

Computerized nuclear morphometry is a useful technique for evaluating the high metastatic potential of colorectal adenocarcinoma

BACKGROUND

Nuclear profiles have been reported to be useful prognostic predictors in various cancers. Data from computerized morphometry are objective and are quickly obtained by conventional microscopic analysis. However, this image analysis of nuclear features has been only rarely applied to investigations of colorectal adenocarcinoma. The aim of this study was to evaluate the correlation between the morphologic nuclear features and clinicopathologic parameters in cases of colorectal adenocarcinoma.

METHODS

Morphometric nuclear features (nuclear area, perimeter, and shape) were analyzed in 343 patients with colorectal carcinoma and in 57 patients with colorectal adenoma. In each case, 300 nuclei of carcinoma or adenoma cells were analyzed on routine hematoxylin and eosin stained slides by means of a computer-assisted image analysis system that involved tracing the nuclear profiles (magnification x400) on a computer monitor. The morphometric data were compared with patients' survival, clinicopathologic status, and DNA ploidy pattern of tumors.

RESULTS

The mean nuclear area (NA) enlarged from normal colorectal mucosa to adenoma and carcinoma (normal mucosa: n = 343, mean NA = 19 micrometer(2); adenoma: n = 57, mean NA = 34 micrometer(2); mucosal carcinoma: n = 15, mean NA = 45 micrometer(2); P < 0.001). In 343 colorectal carcinomas, NAs of cancer cells in tumors with lymphatic invasion, venous invasion, lymph node metastasis, or hepatic metastasis were significantly larger than those of cancer cells in tumors without such factors. The mean NA of DNA aneuploid tumors was larger than that of DNA diploid tumors (P < 0.001). The nuclear area of cancer cells was determined to be one of the independent prognostic factors in multivariate analysis (P < 0.001). Moreover, the large nuclear area of cancer cells was recognized as one of the risk factors of metachronous hematogenic metastasis in patients after curative surgery.

CONCLUSIONS

Data from computerized morphometry are objective and can be obtained rapidly by conventional microscopic analysis. The nuclear area of cancer cells appears to predict 1) the ability of cancer cells to invade the microvessels in the colorectal wall and 2) the ability of cancer cells to metastasize to the lymph nodes or liver. Therefore, nuclear morphometry is beneficial in mass screening to select patients who are at risk of hematogenic or lymph node metastatic recurrence after curative surgery for colorectal carcinoma.

Increased urinary phosphate excretion in pseudohypoparathyroidism type II with long-term treatment with phosphodiesterase inhibitor

A 58-year-old woman was diagnosed to have pseudohypoparathyroidism (PHP) type II because of the absence of an increase of urinary phosphate secretion, despite a marked increase in urinary cAMP excretion on the Ellsworth-Howard test. We treated the patient with a cyclic-nucleotide phosphodiesterase inhibitor, theophylline, resulting in increased urinary phosphate and cAMP excretions. Dibutyl cAMP administration induced the increase in the urinary phosphate excretion. In this case, the unresponsiveness of the urinary phosphate secretion to cAMP was recovered by a high dose of cAMP or long-term administration of a phosphodiesterase inhibitor. These data imply that cAMP responsiveness to renal tubular phosphate reabsorption should be more strictly elucidated in the patient with PHP type II.

Studies on the constituents of Mikania hirsutissima (Compositae)

Two novel norhumulene-type sesquiterpenes, named mikaniahumulene I (1) and II (2) were isolated along with nine known compounds, seven kaurenic acid-type diterpenes (3-9), a coumarin (10) and a flavone (11), from the aerial parts of Mikania hirsutissima DC (Compositae). The structures of new norhumulenes were determined by spectroscopic means. The cytotoxic activities of isolated compounds against leukemia cells (L 1210) were investigated; among the isolated compounds, 1, 5, 8, and 11 showed relatively strong cytotoxicity.

Monocyte-driven activation-induced apoptotic cell death of human T-lymphotropic virus type I-infected T cells

We attempted apoptotic cell death induction of T cells infected with human T lymphotropic virus type I (HTLV-I) which induces HTLV-I-associated myelopathy/tropical spastic paraparesis and adult T cell leukemia. T cells acutely infected and expressing HTLV-Igag Ags were killed by cross-linking their TCR with anti-CD3 mAb. Cells in apoptotic process were found by staining with annexin V. The apoptosis was not affected by costimulation through CD28 molecules and was resistant to ligation of Fas molecules. Whereas the virus-infected T cells expressed higher levels of HLA-DR, CD25, CD80, and CD86 Ags than apoptosis-resistant PHA-blasts, the T cell apoptosis was enhanced by addition of exogenous IL-2. Furthermore, in this apoptosis, monocytes played an important role because T cells infected in the absence of monocytes were resistant to the death signals. The apoptosis-sensitive T cells responded to TCR signaling more strongly by proliferating than those apoptosis-resistant cells. Monocytes weakly affected the expression levels of viral Ags on T cells. However, HTLV-I-infected monocytes primed T cells to die by subsequent TCR signaling. T cells primed with the monocytes, subsequently infected in the absence of monocytes, were killed by TCR signaling. These observations suggest that primed and infected T cells could be killed by activation-induced cell death.

Changes in superoxide dismutase activities and concentrations and myeloperoxidase activities in leukocytes from patients with diabetes mellitus

To investigate whether the two free-radical scavengers, Cu, Zn- and Mn-superoxide dismutase (SOD), are changed in leukocytes of diabetic patients, and the alteration of these enzymes correlates with the diabetic state, we measured the activity and concentration of these enzymes in leukocytes from diabetic patients. Both Cu, Zn-SOD and Mn-SOD activities in neutrophils and lymphocytes were significantly lower in patients with non-insulin-dependent diabetes mellitus than in healthy controls. The concentrations of these enzymes in leukocytes from diabetic patients, however, did not differ from those in controls. Cu, Zn-SOD and Mn-SOD activities in neutrophils inversely correlated with HbA(1c) concentrations. Myeloperoxidase activity in leukocytes was significantly reduced in NIDDM patients. These findings suggest that changes in these enzymes may affect the susceptibility to infection and immunocompetence of patients with diabetes.

The role of human T-lymphotropic virus type 1 (HTLV-1)-infected dendritic cells in the development of HTLV-1-associated myelopathy/tropical spastic paraparesis

The development of human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is closely associated with the activation of T cells which are HTLV-1 specific but may cross-react with neural antigens (Ags). Immature dendritic cells (DCs), differentiated from normal donor monocytes by using recombinant granulocyte-macrophage colony-stimulating factor and recombinant interleukin-4, were pulsed with HTLV-1 in vitro. The pulsed DCs contained HTLV-1 proviral DNA and expressed HTLV-1 Gag Ag on their surface 6 days after infection. The DCs matured by lipopolysaccharides stimulated autologous CD4(+) T cells and CD8(+) T cells in a viral dose-dependent manner. However, the proliferation level of CD4(+) T cells was five- to sixfold higher than that of CD8(+) T cells. In contrast to virus-infected DCs, DCs pulsed with heat-inactivated virions activated only CD4(+) T cells. To clarify the role of DCs in HAM/TSP development, monocytes from patients were cultured for 4 days in the presence of the cytokines. The expression of CD86 Ag on DCs was higher and that of CD1a Ag was more down-regulated than in DCs generated from normal monocytes. DCs from two of five patients expressed HTLV-1 Gag Ag. Furthermore, both CD4(+) and CD8(+) T cells from the patients were greatly stimulated by contact with autologous DCs pulsed with inactivated viral Ag as well as HTLV-1-infected DCs. These results suggest that DCs are susceptible to HTLV-1 infection and that their cognate interaction with T cells may contribute to the development of HAM/TSP.