Catechol oxidation by peroxidase-positive astrocytes in primary culture: an electron spin resonance study.

In rodents, chronic estrogenization has been shown to induce degeneration of dendrites and myelin figures in the hypothalamic arcuate nucleus adjacent to peroxidase-positive astrocyte processes. Because in this brain region estradiol is metabolized to 2-hydroxyestradiol (catecholestrogen), we hypothesized that the latter may be oxidized by the astrocytic peroxidase activity to cytotoxic ortho-semiquinones as occurs in peripheral tissues. Cysteamine induces nonenzymatic peroxidase activity in cultured astroglia identical to that observed in vivo. Using electron spin resonance, we demonstrate robust peroxidase-catalyzed oxidation of 2-hydroxyestradiol and dopamine by cysteamine-pretreated astrocyte cultures relative to untreated controls. These results implicate the peroxidase-positive astrocytes in the pathogenesis of estradiol-related hypothalamic damage, parkinsonism, and other free-radical-related neurologic disorders.     

Blocking effect of 1389-S on the sodium current in isolated guinea-pig ventricular myocytes

Under whole cell patch conditions, 1389-S blocked the INa in guinea-pig ventricular myocytes under steady state conditions (Kdrest = 30 microM, Kdi = 2.4 microM) with a shift of the inactivation curve to the hyperpolarizing direction. Both brief and long conditioning pulses could produce a use-dependent block of 1389-S. These results suggest that 1389-S had a higher affinity to the inactivated than to the rested state under steady state conditions and had a higher affinity to the activated state during train pulses as well as to the inactivated state, making channels unavailable for conduction upon activation.     

A case of renal pelvic carcinoma in situ]

A 72-year-old female visited our hospital with the complaint of macroscopic hematuria on Jan. 29, 1990. Cystoscopic examination revealed hematuria flowing out from the left ureteral orifice. A 1 cm mass was found in the left upper calyx by retrograde pyelography (RP). Urine cytology obtained by RP was class IIIb. Later, the mass was found in the left middle calyx by CT. Repeated RP revealed no mass and the wall of the left upper calyx was irregular. Washing cytology from the left renal pelvis was class V. Left total nephroureterectomy was performed on Feb. 2, 1990. Macroscopically, no tumor mass was apparent. Microscopically, transitional cell carcinoma in situ was widely spread from the left renal pelvis to the middle ureter. The preoperative upper calyceal mass was thought to have been a blood clot. At twelve months after the operation, there has been no evidence of tumor recurrence.     

Uveitis and immune responses in primates immunized with IRBP-derived synthetic peptides

Monkeys immunized with bovine IRBP-derived synthetic peptides R4 (sequence 1158-1180) or R14 (1169-1191) developed EAU which was detected by both clinical and histological examinations. The inflammation localized mainly in the choroid, with only minor changes being noticed in the adjacent retinal tissue. EAU developed in only one of the two monkeys immunized with each of the peptides and the animals with disease also showed higher levels of cellular immunity toward the immunizing peptide than did the monkeys with no disease. The cellular immune responses, measured by the lymphocyte proliferation assay, were specific toward the immunizing peptides, with no cross responsiveness to whole IRBP. This finding suggests that the two uveitogenic peptides were non-immunodominant in the tested monkeys. In contrast, peptide R14 is highly immunodominant in the Lewis rat. Also, the fine specificity of the monkey response to R14 differed from that of the Lewis rat. The possible genetic control of the monkey susceptibility to EAU induction by the peptides is discussed and the unique finding of an autoimmune disease induction by a non-immunodominant peptide is underscored.     

Production of monoclonal antibodies against human bladder cancer cells and application to immunohistochemical analysis of bladder cancer

Two hybridomas secreting two monoclonal antibodies IgG1 B1.4 and IgG2a B1.6 were obtained by immunizing BALB/c mice with human bladder cancer cell line EJ-1. In immunohistochemical staining of cryopreserved tissues, B1.4 reacted with 0 of 9 grade 1 TCC, 6 of 11 grade 2, all of 6 grade 3 and five metastatic specimens. The antigen recognized by B1.4 was not expressed by normal urothelial cells but were expressed by vascular endothelial cells and muscle of tunica media. The target antigen of B1.6 was expressed by normal urothelial cells and all grade of TCC. In this study, it was demonstrated that poorly differentiated bladder cancer and metastatic specimens of bladder cancer express a vascular carbohydrate antigen. Taking the escape mechanism of immune surveillance, into consideration, it is possible that the antigen recognized by B1.4 is an indicator of metastatic potential of bladder cancer.     

Effect of intermittent parathyroid hormone (1-34) treatment on the bone response after placement of titanium implants into the tibia of ovariectomized rats.

PURPOSE: This study investigated the effect of parathyroid hormone (1-34) [PTH(1-34)] on bone reactions after tibial placement of titanium screw implants into ovariectomized rats. MATERIALS AND METHODS: Twelve-week-old female Wistar rats were divided into 3 groups of 24. The first group (Sham group) was sham-operated; the second group (OVX group) was ovariectomized only; and the third group (PTH group) was subcutaneously administered 30 microg/kg PTH in the dorsal region 3 days per week starting the fourth week after ovariectomy until the end of the experiment. Titanium screw implants were placed in the proximal metaphysis of the tibia of all 3 groups at 168 days after surgery. The animals were killed 7, 14, 28, and 56 days after implantation. Undecalcified sections were prepared and evaluated by light microscopy. Histomorphometric measurements were obtained using a computer-based image analyzer to quantify the unit bone mass around the implant and the rate of implant-bone contact. RESULTS: When PTH administration was started 21 days after ovariectomy, the volume density of bone around implants in the PTH group was almost the same as that of the Sham group throughout the entire observation period. This finding suggests that not only can intermittent human PTH(1-34) administration prevent resorption of newly generated trabeculae around an implant but also it can aid in the recovery of bone volume lost due to ovariectomy. CONCLUSION: When dental implants are applied to jaw bone showing trabecular bone loss, it may be possible to increase bone density around an implant by intermittent human PTH(1-34) administration and thereby improve clinical results.     

Two cases of persistent hypouricemia associated with diabetes mellitus.

Two patients with diabetes mellitus had persistent hypouricemia due to increased urate clearance; the degree of the apparent renal hypouricemia with uricosuria was quite mild. At the onset of diabetes, their serum urate levels were normal. Even after good diabetes control in both cases, hypouricemia continued. Based on the pharmacological evaluation in both patients, pyrazinamide administration could partially decrease urate clearance, however, suppression by pyrazinamide was less than in normal subjects, and probenecid increased urate clearance. These results suggest that the present cases had a renal abnormality affecting tubular presecretory reabsorption of urate, which might be due to diabetes mellitus.     

Quartromicin, a complex of novel antiviral antibiotics. I. Production, isolation, physico-chemical properties and antiviral activity.

A strain of Amycolatopsis orientalis No. Q427-8 (ATCC 53884) was found to produce a complex of new antiviral antibiotics, quartromicin which consisted of at least six components A1, A2, A3, D1, D2 and D3. Structural studies suggested that they are a novel type of molecules unrelated to any known antibiotics. Each component of quartromicin exhibited antiviral activity against herpes simplex virus type 1, influenza virus type A and human immunodeficiency virus.     

Study on local recurrence of squamous cell carcinoma of the lung on hilar lesion

The study population consisted of 62 patients with squamous cell carcinoma of the lung on hilar lesion who underwent curative or relative curative resection during the seven year period between January, 1980 and December, 1986. We studied the correlation between local recurrence and the distance from the surgical margin of the trachea or bronchus to the tumor. 1) As the classification of the T and N factors increased, the incidence of local recurrence became higher. 2) In order to prevent local relapse, we need to completely resect the hilar and mediastinal lymph nodes, and we must maintain a distance of 16 mm or more between the surgical margin of the trachea or bronchus and the tumor.