[Experimental techniques for developing new drugs acting on dementia (1)--Senescence-accelerated mouse: neurochemical approaches and the findings]

The senescence-accelerated mouse (SAM) was established by Takeda et al (1991) as a model of accelerated aging. A P/8 strain of SAM spontaneously shows learning and memory disturbances with increasing age. Several neurochemical markers were examined in the brain of mice of P/8 strain and were compared with those in the R/1 strain as a control. Here, the author describes neurochemical methods and our findings obtained by the methods regarding measurement of: 1) the glutamate content, 2) release of glutamate and acetylcholine (ACh) from brain slices, 3) ligand bindings to neurotransmitter receptors (NMDA, muscarinic ACh), protein kinase C and glial cells and 4) mRNA expression and metabolism of amyloid precursor protein (APP).

[The two cases of examination of chemotherapy in advanced gallbladder carcinoma]

Two cases of advanced carcinoma of gallbladder were treated by combination chemotherapy consisting of 5-FU, leucovorin and continuous administration of etoposide. One of the cases was a male 61 years old and another was a female 64 years old, both of whom were diagnosed as inoperable cases by imaging studies. When combination chemotherapy consisting of 5-FU (750mg/day or 1,000mg/day infusion) was given, leucovorin (30mg/day) and etoposide (25mg/day oral or 33mg/day continuous infusion), angiography or other imaging studies pointed out a reduction in their lesions of over 50%, and their QOL was markedly improved.

Relative glucocorticoid potency revisited

To determine the relative potency of synthetic glucocorticoids, glucocorticoid receptor expressing cells were transfected with a hormone-inducible reporter gene, and were cultured in the presence of various glucocorticoid ligands. Hormonal inducibility was determined by means of a chloramphenicol acetyltransferase assay. Dexamethasone and prednisolone, as well as cortisol, induced the expression of the reporter gene in a dose-dependent fashion. The relative potency of each ligand was in this order when inducibility was quantitatively assessed. In conclusion, the transcription assay described here may be a convenient and alternative method to evaluate the relative potency of given glucocorticoids.

Acceleration of desipramine-induced changes on the dopamine receptor-coupled adenylate cyclase system by pertussis toxin

The response of adenylate cyclase to GTP and to dopamine (DA) was investigated in striatal membranes from desipramine (DMI)-treated rats (10 mg/kg, b.i.d., for 5 days). GPT exerted the same biphasic effect on basal and DA-stimulated enzyme activity in membranes from DMI-treated rats as on saline-treated rats. Rats were injected intraventricularly once with islet activating protein (IAP), pertussis toxin, and given extended treatment with DMI in order to study the effects on the inhibitory GTP-binding protein (Gi). Gi loses its function as a signal transducer on being ADP-ribosylated selectively by the IAP. D2 inhibition of adenylate cyclase by DA was attenuated by the IAP treatment in both DMI-and saline-treated rats; peak levels of DA plus GTP stimulation shifted from 1 microM to 100 microM GTP. D1 stimulation of adenylate cyclase by DA was also attenuated by the IAP in the DMI-treated rats. Since long-term treatment with DMI (15 mg/kg, once a day, for 3 weeks) resulted in suppression of D1 stimulation similar to that seen in the present findings, uncoupling between D2 receptors and Gi due to IAP treatment might accelerate DMI-induced adaptive changes of dual control of adenylate cyclase system by DA.

[An evaluation of "now" (Japanese ima) in the process of cognition and solution of contradictory situations]

This study examines the relationship between the process of cognition and solution in contradictory situations and evaluation of the span comprehended by "now" (Japanese ima) in it. Eighty-eight subjects were asked to express the span of "now" in each of 24 contradictory situations, selected for and graded according to degree of both contradictoriness and solvability. The subjects expressed their evaluation on a bi-directional cline, comprising 21 time categories: in this cline, "now" is positioned in the center, and the categories of second, minute, hour, day, week, year, generation, century, and infinity to both the left for the past and the right for the future. Three coordinates emerged from the data, applying Dual Scaling. The first indicated that future-oriented solutions in contradictory situations generate wider spans of "now" than did past ones, the second that negative solutions to contradictions generate a less realistic interrelation between its self and his outside world than did positive ones, and the third that the cognitive process and that by which contradictory situations are solved contain a third dimension, different from both a past-future dimension and a positive-negative dimension.

A nine-year chronic toxicity study of cadmium ingestion in monkeys. I. Effects of dietary cadmium on the general health of monkeys

Thirty-five male rhesus monkeys (Macaca mulatta) 2-5 y-of-age were separated into 5 groups and fed 200 g solid food daily which contained 0, 3, 10, 30 or 100 micrograms cadmium/g (ppm) as cadmium chloride for 462 w (9 y). The control feed (0 ppm) contained 0.27 micrograms cadmium/g. Dietary zinc intake was limited to the minimum requirement of 6 mg zinc/day (control food concentration was 3 mg zinc/100 g) to avoid impacting cadmium toxicity due to excessive zinc intake. Urine was collected at 3-w intervals. Decreased development (reduced body weight and body length) was observed in groups that received 10 ppm cadmium or more. The 100 ppm group had glucose in the urine after 48 w, elevated urine protein at 98 w, and markedly increased urine volume after the 102nd week. No abnormalities in renal functions were noted in the 3 or 10 ppm groups. Despite the development of these clinical signs of renal dysfunction, none of the 100 ppm group had aggravated renal dysfunction or renal failure during the 9 y of study.

[Early phase II study of KW-2307 in advanced or recurrent breast cancer. KW-2307 Cooperative Study Group (Breast Cancer Section]

A multi-institutional early phase II study of KW-2307 (vinorelbine), a new vinca alkaloid derivative, in advanced or recurrent breast cancer was conducted in 15 nationwide hospitals. KW-2307 was intravenously administered once weekly at doses of 15 to 25 mg/m2. Sixty-five among the enrolled 69 patients were eligible. Response rates were 11.8% (2/17) with 15 mg/m2, 28.0% (7/25) with 20 mg/m2 and 17.4% (4/23) with 25 mg/m2, and the overall response rate was 20.0%. Once-weekly intravenous administration of 20 mg/m2 was estimated to be the optimal dose of KW-2307 from the results. The major side effect was leucopenia, which was the dose-limiting factor in this study. Other subjective or objective side effects included anorexia, nausea-vomiting, phlebitis, fever, general fatigue and stomatitis, but none of them was serious.

[Late phase II study of KW-2307 in advanced or recurrent breast cancer. KW-2307 Cooperative Study Group (Breast Cancer Section)]

A multi-institutional late phase II study of KW-2307 (vinorelbine), a new vinca alkaloid derivative, in advanced or recurrent breast cancer was conducted in 26 nationwide hospitals. KW-2307 was intravenously administered at a dose of 20 mg/m2 once weekly. Eighty among the enrolled 82 patients were eligible. The overall response rate was 30.0% (24/80) with 4 CR, 20 PR, 5 MR, 22 NC, 17 PD and 12 unevaluable patients. The major side effect was leucopenia, which was the dose-limiting factor in this study. Other subjective or objective side effects included general fatigue, nausea-vomiting, anorexia, paresthesia, fever and stomatitis, but none of them was serious.

Alterations in glomerular anionic sites in canine anti-glomerular basement membrane nephritis with onset of severe proteinuria

Rabbit anti-glomerular basement membrane serum (AGBM) or normal rabbit serum (NRS) were given intravenously (2 ml/kg body weight) to 8 male beagle dogs. Light and transmission electron microscopy and immunofluorescence were performed on the kidneys on day 7 postinjection. Alterations of anionic sites (ASs) of glomerular basement membrane (GBM) in peripheral, proximal, and paramesangial portions were studied quantitatively by electron microscopy using polyethyleneimine (PEI; molecular weight = 1,800) as a cationic probe. Severe or mild proteinuria developed on day 1 and continued until day 6 postinjection. On day 7 after AGBM injection, the number of PEI granules per 1,000 nm length of the lamina rara externa of GBM in all portions was significantly less than that in NRS-treated dogs (10.48 +/- 1.78 versus 14.19 +/- 2.35 granules per 1,000 nm of GBM in peripheral portion, 10.81 +/- 1.91 versus 14.97 +/- 1.35 granules per 1,000 nm of GBM in proximal portion, 8.44 +/- 1.76 vs 13.43 +/- 2.10 granules per 1,000 nm of GBM in paramesangial portion; p < 0.001). These results indicate that a reduction glomerular AS occurs in AGBM-treated dogs in association with severe or mild proteinuria and alterations in glomerular ASs might play an important role in the pathogenesis of proteinuria in the canine anti-GBM nephritis in addition to morphological changes.

Unique intronic variations of HLA-DQ beta gene in early-onset periodontitis

Human leukocyte antigen (HLA) class II beta chain plays an important role in the recognition of foreign antigens in immune reactions. Different forms of immune reaction may be concerned with initiation and progression of infectious diseases such as periodontitis. In this study we examined the frequency of HLA class II serotype and the variation of HLA class II beta gene in periodontitis patients. HLA serotypic frequencies in 70 Japanese patients with periodontitis and 26 individuals with periodontal health were examined. No HLA serotype specific to any type of periodontitis was observed. In order to detect differences among some HLA serotypes, restriction fragment length polymorphism (RFLP) analysis was undertaken with cDNA probes for HLA-DR beta and HLA-DQ beta genes in 20 subjects (15 patients and 5 healthy individuals). Atypical BamHI and EcoRI restriction sites were found in the HLA-DQ beta gene from 3 patients with early-onset periodontitis. In addition to these 20 subjects, an additional 80 subjects (40 patients and 40 healthy individuals) were screened for the atypical BamHI restriction site using the polymerase chain reaction method. It was detected in 7 patients with early-onset periodontitis, 1 patient with adult periodontitis, and 3 healthy subjects. No clinical differences except age were found between patients with this gene variation and other patients. Interestingly, all 3 healthy subjects with this gene variation were from subjects whose family members developed early-onset periodontitis with the gene variation. Atypical BamHI and EcoRI restriction sites and 41-nt repeated sequence were found in the intron before the third exon of HLA-DQB gene. These results suggest that these intronic gene variations may be useful as gene markers for a subpopulation of early-onset periodontitis and might affect immune reactions such as antigen recognition.

Relationship between the degree of injury at operation and the change in antimyosin antibody titer in the postpericardiotomy syndrome

Successive measurements of cardiac myosin light chain I (MLC), creatine kinase isoenzyme MB (CKMB), and the titer of antimyosin antibody (AMA) were performed prospectively in 19 patients following open heart surgery. Seven of these patients showed the postpericardiotomy syndrome (PPS). No differences in serum concentrations of MLC or CKMB were observed between the patients with and without PPS, and all patients in both groups had abnormal MLC values after surgery. However, only patients with PPS had significantly elevated AMA titers. The maximum AMA titer was significantly correlated with the severity of the effusion. These data suggest that PPS is unrelated to the severity of myocardial injury during operation. Furthermore, the AMA titer may be useful as one of the indicators for determining the patient's clinical condition.

Expression of adult and fetal natural killer cell markers in sinonasal lymphomas

The majority of sinonasal non-Hodgkin's lymphomas (NHLs) are thought to originate from T-cell lineage. However, they often express natural killer (NK)-cell markers so that their origin still remains obscure. In this study, cell type of sinonasal NHLs were characterized by immunohistochemical and Southern blot analyses. We examined nine patients with sinonasal NHL. Six patients with tonsillar or pharyngeal non-B-cell lymphomas served as a control group. Immunohistochemical study showed that all nine cases of sinonasal NHL were CD56+CD2+, whereas controls were CD56-CD2+. According to the rearrangement of T-cell receptors (TCRs) and expression of CD3 markers, the sinonasal NHL cases were classified into three groups: TCR-CD56(Leu-19)+CD3(Leu4)- NHL (three patients), TCR-CD56+CD3+ NHL (five patients), and TCR+CD56+CD3+ NHL (one patient). In contrast, control patients' NHLs were TCR+CD56-CD3+. These results imply that eight cases of TCR-CD56+ sinonasal NHL are of NK-cell lineage. Among these eight cases, TCR-CD56+CD3+ cases (five of eight patients) were rather similar to the phenotype of fetal NK cells. From these results, the majority of sinonasal NHLs seem to originate from varying maturation stages of NK-cell lineage.

Splenic hamartoblastoma in a sow

Multiple lesions of splenic hamartoblastoma were found incidentally in a 2- to 3-year-old crossbred sow. The predominant cells, characterized by extreme nuclear irregularity and hemidesmosome-like structures, were considered to be derived from reticular cells of the spleen, and demonstrated infiltrative growth. Their cytological atypism and growth pattern suggest that the present lesions are true neoplasms.

[Urogenital sinus cyst in a child. A case report]

A rare case of urogenital sinus cyst in a child is reported. A 10-month-old boy was referred to our hospital under the diagnosis of acute epididymitis. IVP showed left hydronephrosis and round filling defect in the bladder. Ultrasonography and CT scan demonstrated a retrovesical cystic lesion. Right vesiculography under general anesthesia revealed a midline cystic lesion. Fenestration between the prostatic urethra and cystic lesion was performed by TUR-velmontanum. However, that cystic lesion did not disappeared. Our case seems to be the youngest case of urogenital sinus cyst reported in the Japanese literature.

Role of cholinergic neurotransmission in the amygdala on performances of passive avoidance learning in mice

To clarify the role of cholinergic neurons in the amygdala on learning and memory, scopolamine was injected topically into the bilateral amygdala of mice, and the ability to perform two types of passive avoidance tasks (step-through and step-down) was investigated. On the first day mice performed the learning trial and on the second day their retention was tested. Scopolamine (0.5 or 1 microgram/site) was injected bilaterally into the amygdala 30 min before or immediately after the learning trial or 30 min before the testing trial. Scopolamine impaired the performance ability of the mice dose-dependently only when it was injected 30 min before the learning trial. The results coincided well with the effect of scopolamine injected intraperitoneally. Taken together, these results suggest that the site of action for scopolamine to cause anterograde amnesia is the amygdala, and that cholinergic neurons projecting to the amygdala play an important role in memory acquisition in the two passive avoidance tasks.

Successful engraftment of autologous and allogeneic islets into the porcine thymus

Work in rodents has shown that injection of pancreatic islets of Langerhans into the thymus can induce donor-specific unresponsiveness to islets subsequently transplanted to extrathymic sites. The overall objective of our investigation is to test this in a large animal (pig) model. In the current study we examined whether autologous and allogeneic adult or fetal islets survive in the porcine thymus. Collagenase-digested adult and fetal porcine islets were injected into the thymic lobes of 5- to 13-month-old, normal pigs. Pigs receiving allografts were given either a standard triple regimen of oral cyclosporine, azathioprine, and prednisone or intravenous anti-lymphocyte globulin (ALG) for immunosuppression. Two pigs of each group that received an allograft or autograft were given no immunosuppression. Biopsies of the grafts were taken at 4, 6, or 12 weeks for examination. Islet survival was assessed by histology with hematoxylin and eosin and insulin staining and by measurement of tissue insulin content using acid alcohol extraction and radioimmunoassay. The insulin content of control thymus was found to be 0.71 +/- 0.29 microU/mg (n = 5). The insulin content of the islet-grafted thymic tissues ranged from 1.57 to 10.65 microU/mg. Since the amounts of injected islets were not equal and not distributed evenly, and only a part of the graft site was used for determination of tissue insulin, thymic insulin contents higher than 1.4 microU/mg (twice that of the control value) were considered to demonstrate the presence of viable islets. With this criterion, we concluded that islets were found to be viable in seven of nine pigs and two pigs which were treated with ALG were shown to be marginally positive. On histological examination, islets were found in the thymus as well as under the thymic capsule, except for the above two pigs. These results demonstrate that the pig thymus supports fetal and adult islet transplants.

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.