Mental fatigue-induced decrease in levels of several plasma amino acids.

To investigate the relation between plasma amino acid levels and mental fatigue, we measured the plasma concentrations of 20 amino acids in 9 healthy volunteers before and after a fatigue-inducing mental task session for 8 hr. As fatigue-inducing mental tasks, the subjects performed an advanced trail making test, a Japanese KANA pick up test, and a mirror drawing test. As a control, 8-hr relaxation session was performed in the same subjects at an interval of 4 weeks. Immediately after the fatigue session, the plasma levels of branched-chain amino acids, tyrosine, cysteine, methionine, lysine, and arginine were below those after a relaxation session. The values for other blood parameters including total protein, albumin, glucose, and total cholesterol did not show any differences between the 2 sessions. These results indicate that mental fatigue may be characterized by a decrease in the plasma level of these amino acids.

Cysteine conjugate of methazolamide is metabolized by beta-lyase.

Bovine kidney and liver homogenates degraded a cysteine conjugate of methazolamide, S-(5-acetylimino-4-methyl-Delta2-1,3,4-thiadiazolin-2-yl)cysteine. We isolated the degradation product following incubation with kidney homogenate by high-performance liquid chromatography on reversed-phase columns. The chemical structure was confirmed by proton and carbon-13 nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR, respectively), and elemental analysis by high-resolution mass spectrometry to be N-(3-methyl-5-mercapto-Delta4-1,3,4-thiadiazol-2-yl)acetamide, a thiol compound. The reaction is thought to be catalyzed by a pyridoxal-dependent enzyme(s) as indicated by an inhibition study using aminooxyacetic acid. Possible involvement of the thiol compound in the development of an adverse effect is discussed.

Concentration dependent effects of hydrogen peroxide on lens epithelial cells.

AIMS: To evaluate the effects of hydrogen peroxide exposure on the survival and proliferation of cultured lens epithelial cells. METHODS: TOTL-86 cells, a line of rabbit lens epithelial cells, were used. The survival and proliferation of TOTL-86 cells were quantified by a rapid colorimetric assay (MTT assay). To determine the effects of hydrogen peroxide, TOTL-86 cells were exposed to different concentrations of hydrogen peroxide. To determine the effect of cell numbers on the survival and proliferation of TOTL-86 cells at a fixed concentration of hydrogen peroxide, different numbers of cells were plated and exposed to hydrogen peroxide. To determine whether there is a synergistic effect between hydrogen peroxide and EGF, bFGF, PDGF-AA, and insulin, TOTL-86 cells were exposed to hydrogen peroxide combined with one of these growth factors. RESULTS: High levels (1 mM) of hydrogen peroxide killed TOTL-86 cells and sublethal levels (100 microM) suppressed their proliferation. From 1 nM to 1 microM of hydrogen peroxide, there was a dose dependent increase in the cell numbers. The initial seeded cell number dramatically affected the response to hydrogen peroxide. Although growth factors showed no synergistic effects with hydrogen peroxide on proliferation, both EGF and insulin, but not bFGF or PDGF, rescued TOTL-86 cells from the sublethal effect. CONCLUSION: Hydrogen peroxide in cooperation with some growth factors plays an important role in the proliferation of lens epithelial cell.

[Cataracts occur in patients with atopic dermatitis when the serum IgE increases].

The serum-IgE (sIgE) levels of eight patients with cataract complicated by atopic dermatitis (atopic cataract) who had undergone cataract surgery were reported. Five of them were diagnosed as having cataract the first visit to our eye clinic. The other three cases did not show cataract at the first visit but developed it later. The average sIgE of the five cases with cataract was 25,478 +/- 15,936 (mean +/- standard deviation) iu/ml whereas that of the latter three cases without cataract, at the first visit was 4,638 +/- 1,810 iu/ml. The average sIgE of these three cases when their cataracts were diagnosed first went up to 13,210 +/- 5,574 iu/ml. These results suggested that a high level of sIgE may be a warning of the appearance of atopic cataract.

[The inhibitory effects of Arg-Gly-Asp-Ser on attachment of fibroblasts].

Trabeculectomy often fails because of scarring of the filtering bleb, which is caused by the proliferation of fibroblasts. In this study, we investigated the inhibitory effect of Arg-Gly-Asp-Ser (RGDS) oligopeptide, a cell binding domain of fibronection molecules, on the attachment of fibroblasts in vitro and on scarring of filtering bleb after trabeculectomy on rabbits' eyes. The following results were obtained. 1. RGDS inhibited the attachment of rabbit conjunctival fibroblasts significantly (p < 0.01) when it was added to the culture medium at final concentrations of 2 and 5 mg/ml. 2. The administration of 0.2 ml of RGDS solution (5 mg/ml) into the filtering bleb 3 days after surgery caused significant reductions of intra ocular pressure compared with the control maintained the bleb more than 13 days whereas the blebs of the control eyes disappeared within 6 days (p < 0.01). 3. No complications were caused on the eyeballs of the rabbits by the administration of RGDS.

Differential effects of fibronectin-derived oligopeptides on the attachment of rabbit lens epithelial cells in vitro.

Among the Arg-Gly-Asp (RGD)-containing sequences that are known to be cell-binding domains of fibronectin, 500 migrograms/ml of Arg-Gly-Asp-Ser (RGDS) and Gly-Arg-Gly-Asp-Ser showed 100% inhibition of the attachment of cultured lens epithelial cells (TOTL-86 cells), when they were added to culture medium and coincubated with the cells for 24 h whereas RGD at concentrations of 500, 1,000 and 2,000 micrograms/ml had no such activity. After 48 h of cocultivation of 800, 400 or 200 micrograms/ml of RGDS with TOTL-86 cells, the percentage of floating cells was 100, 30.1 or 11.1%, respectively. After 144 h of cocultivation with RGDS, the percentage of floating cells was 1.6, 2.4 or 1.9%, respectively, indicating that RGDS was not cytotoxic to lens epithelial cells. However, replacing the medium with fresh medium containing new RGDS peptide resulted in floating of cells. We also studied the inhibitory effect of two other amino acid sequences that are found in cell-binding sites of the fibronectin molecule: Glu-Ile-Leu-Asp-Val-Pro-Ser-Thr (EILDVPST) and Arg-Glu-Asp-Val (REDV). At 500 and 1,000 micrograms/ml, respectively, neither EILDVPST nor REDV has an inhibitory effect on the attachment of TOTL-86 cells, while RGDS at a concentration of 500 micrograms/ml completely inhibited the attachment of the cells in 24 h of incubation.

An SV40-immortalized human corneal epithelial cell line and its characterization.

PURPOSE: The authors attempted to immortalize human corneal epithelial cells; it is difficult to propagate primary human corneal epithelial cells because of scarcity of available tissue. However, cell immortalization by virus is always accompanied by shedding of free virus. The current study was performed to establish a cell line that produces no free viral particle. METHODS: Primary cultured human corneal epithelial cells were infected with a recombinant sv40-adenovirus vector and were cloned three times to obtain a continuously growing cell line. Morphologic, cytologic, and biochemical characteristics of this cell line were analyzed. RESULTS: This cell line continued to grow for more than 400 generations, exhibiting a cobblestone-like appearance similar to normal corneal epithelial cells in culture. Transmission electron microscopy showed the evidence for the characteristic features of epithelial cells, including desmosome formation and development of microvilli. It expressed cornea-specific, 64-kD cytokeratin in addition to five major insoluble proteins. By enzymatic analysis using NADP as a coenzyme and a gas chromatograph mass spectrometer, this cell line was found to possess 8.71 IU/mg protein of aldehydedehydrogenase activity. When this cell line was grown at air-liquid interface on collagen type I gel, it differentiated in a multilayered fashion. CONCLUSIONS: The authors have established an SV40-immortalized human corneal epithelial cell line with properties similar to normal corneal epithelial cells.

Safety and efficacy of intraperitoneal injection of etoposide in oil suspension in mice with peritoneal carcinomatosis.

We compared the safety and efficacy in mice with peritoneal carcinomatosis of two etoposide formulations: an aqueous solution (Etp-sol) and particles suspended in oil (the addition products of iodine and the ethyl esters of the fatty acids obtained from poppy-seed oil (Lipiodol) or sesame oil; Etp-oil). We also investigated tissue distribution of etoposide in rats treated with Etp-oil and Etp-sol. Etoposide was injected intraperitoneally at concentrations ranging from 52 to 392 mg/kg (increasing geometrically by a factor of 1.4). The 50% lethal dose (LD50), determined over a 2-week period of observation, was 135 mg/kg for Etp-oil and 108 mg/kg for Etp-sol. Autopsy findings included macroscopic intestinal bleeding, necrosis of the intestinal mucosa, and pulmonary congestion in mice from both treatment groups. In the efficacy trials. 10(6) P388 leukemia cells were transplanted into CDF1 male mice, and Etp-oil and Etp-sol were injected at doses of 20 mg/kg and 80 mg/kg. In the groups receiving the 20 mg/kg dose, 11 of 19 mice in the Etp-oil group survived to day 60 compared with 3 of 20 mice in the Etp-sol group. Toxicity-related deaths occurred in 1 of 20 mice treated with 80 mg/kg Etp-oil and in 8 of 20 mice treated with 80 mg/kg Etp-sol. No cancer-related deaths were associated with the 80 mg/kg dose in either treatment group. Our findings showed that the Etp-oil was associated with a lower toxicity and a higher efficacy than the Etp-sol. To evaluate tissue distribution, rats were injected intraperitoneally with 5 mg/kg body weight of Etp-sol or Etp-oil. The tissue distribution of etoposide was subsequently analyzed by high performance liquid chromatography. Compared with Etp-sol, Etp-oil delivered significantly greater amounts of etoposide and for a longer period to the omentum, taken as representative of the intraperitoneal tissue, and the etoposide concentration in blood plasma was increased more slowly and decreased more gradually.

A rapid method for isolation of retinal pigment epithelial cells from rat eyeballs.

A new, simple method for isolating retinal pigment epithelial (RPE) cells from rat eyeballs was developed: incubation of the eyeballs in 0.1% proteinase K solution. This method yielded an average of 4 x 10(4) viable RPE cells from each Sprague-Dawley rat eyeball in 1 h. These RPE cells were hexagonal and had cytokeratin in their cytoplasm and numerous microvilli on their surface, similar to RPE cells evaluated in vivo. The results of this study thus show that our method for incubating eyeballs in proteinase K can provide good-quality RPE cells in sufficient quantities for study in a short time.

[Eye complications in atopic dermatitis].

Eye complications were studied in 240 cases of atopic dermatitis (age distribution 9 months to 40 years) hospitalized in the dermatology ward of our hospital. One hundred and thirty-four patients (55.8%) had at least one eye complication. Allergic conjunctivitis, cataracts, vernal conjunctivitis, retinal detachment, keratoconus, and retinal tears were detected in 28.3%, 17.9%, 2.1%, 1.3%, 1.3%, and 0.8%, respectively. Serum IgE levels and eye complications did not correlate. Routine ophthalmological examinations are recommended for patients with atopic dermatitis.

[The effect of cultivation on the differentiated function of rabbit lens epithelial cells in vitro].

Changes in the characteristics of rabbit lens epithelial cells during long-term cultivation were examined. From the beginning of cultivation to the 24th generation, the cells grew exponentially, and then the growth stopped. This growth-arrested period lasted for 60 days, and then they grew exponentially again. The cells had a cobblestone-like appearance through the whole cultivation period except in the growth-arrested period. In an immunofluorescence examination with a monoclonal antibody against alpha-crystallin, all of the primary cells and the cells in the 20th generation showed specific fluorescence to alpha-crystallin throughout their cytoplasm. However, some of the cells in the 24th generation did not show this fluorescence, and all of the cells in the 35th and 70th generations showed fluorescence only around the nuclei and none in the cytoplasm. The primary cells and the cells in the 20th generation were capable of forming lentoid bodies, but the cells after the 24th generation were not. These results indicate that some of the characteristics of the rabbit lens epithelial cells are lost during the growth-arrested period.

[Immortalization of rat corneal epithelial cells by SV40-adenovirus recombinant vector].

Using a SV40-adenovirus recombinant vector, we have successfully established a rat corneal epithelial cell line (RatCE) and studied its biological characteristics. RatCE continued to grow for more than 400 generations. It proliferated centrifugally in the early phase of the culture (1-3 days in culture) and had a cobblestone-like appearance in confluency. Desmosomes and microvilli were clearly seen under a transmission electron microscope. RatCE could be stored in liquid nitrogen and its biological characteristics were: doubling time, 18.3 hrs, colony forming ability, 36%, and growth ability in soft agar, 2%. When the insoluble extract from RatCE was electrophoresed, insoluble proteins were seen at 36 kD, 40 kD, 44 kD, 48 kD, 56 kD, and 64 kD. Anti-64 kD cytokeratin antibody strongly reacted with numerous filaments in the cytoplasm of RatCE. Hence, RatCE possessed 64 kD corneal specific keratin. A large amount of fibronectin was also assessed at focal contact by immunohistochemistry. Thus, RatCE retains several kinds of epithelial characteristics, is derived from one clone, and is immortalized. RatCE will be a useful tool in studies of the corneal epithelium.

[Rapid growth of eyelid squamous cell carcinoma in elderly patients with multiple cancers].

Two cases of squamous cell carcinoma of the eyelid are reported. Both patients had multiple cancers. Case 1 was an 81-year-old man who had a squamous cell carcinoma on his right upper eyelid and on his right palm, and Bowen's disease in his left thumb. Case 2 was an 87-year-old woman who had a squamous cell carcinoma on her right lower eyelid, an adenocarcinoma in her colon, and a uterus cancer of unknown histology. In spite of their advanced age, the eyelid tumors showed rapid growth in both cases. The reason for this rapid growth was unclear. However, the presence of cancers in other organs may provide clues, because the immunological ability in patients with multiple cancers is considered to be weakened.

Immortalization of rabbit corneal epithelial cells by a recombinant SV40-adenovirus vector.

PURPOSE: Cultured corneal epithelial cell is detrimental because of its short life span and its heterogeneity. We have tried to establish an immortalized epithelial cell line. METHODS: Primary cultured rabbit corneal epithelial cells were infected with a recombinant SV40-adenovirus vector and were cloned three times. RESULTS: The immortalized cell continued to grow by more than 400 generations through 100 passages. SV40-associated large T antigen was demonstrable on the nuclear membrane of these immortalized cells by immunofluorescence technique. This cell line exhibited a similar cobblestone-like appearance as normal corneal epithelial cells. Transmission electron microscopy showed a line of evidence for stratification, including desmosome formation and microvilli development at the superficial cell layer. As the culture grew, these cells began to express cornea-specific 64 kD cytokeratins. In contrast to cultured normal corneal epithelial cells, this cell line had a good proliferative ability after a long-term storage in liquid nitrogen. CONCLUSIONS: Because this particular cell line shares properties consistent with normal corneal epithelial cells and is easy to handle in vitro, it may serve as a useful tool in corneal epithelial research.

Pharmacologic effects of cisplatin microspheres on peritoneal carcinomatosis in rodents.

BACKGROUND: A new drug-delivery formulation of cisplatin, whereby cisplatin was incorporated in lactic acid oligomer microspheres (CDDP-MS), has been developed in dosage form for peritoneal carcinomatosis and has been designed to release 70% of the incorporated cisplatin slowly during a period of 3 weeks. In this study, its pharmacologic effects were examined in rodents. METHODS: CDDP-MS was tested to determine (1) tissue distribution of cisplatin after intraperitoneal administration of cisplatin at 3.0 mg/kg body weight to rats, (2) acute toxicity in mice when injected intraperitoneally, and (3) therapeutic effects on peritoneal carcinomatosis induced by transplantable M5076 tumors in mice. RESULTS: These experiments revealed the following: (1) CDDP-MS resulted in a higher cisplatin concentration in tissues adjacent to the peritoneum for a longer period, and the concentration of cisplatin measured in the rest of the body was lower than that delivered by the cisplatin aqueous solution; (2) the 50% lethal dose value, determined by the Litchfield-Wilcoxon method, was 23.8 mg/kg body weight in CDDP-MS in terms of cisplatin, whereas in the cisplatin aqueous solution it was 13.5 mg/kg body weight; (3) CDDP-MS enhanced therapeutic effects when compared with the same toxicity dosage of cisplatin aqueous solution. CONCLUSIONS: Intraperitoneal CDDP-MS releases cisplatin into the peritoneal cavity for a long time, and it results in less systemic toxicity and greater therapeutic effects on peritoneal carcinomatosis than does cisplatin aqueous solution.

Spontaneously arising immortal cell line of rat retinal pigmented epithelial cells.

A continuous cell line of rat retinal pigment epithelium (RPE), named BPEI-1, has been established and characterized. Sheets of pure RPE cells, uncontaminated by choroidal or neural retinal cell types, were isolated from eyes of 7-day-old Long Evans rats and established in primary culture. The primary RPE cells became extensively spread and grew slowly for approximately 1 month, at which time a colony of small rapidly dividing cells spontaneously appeared. Following trypsinization, most of the typical primary RPE cells did not survive and were quickly outnumbered by the smaller cells, which gave rise to a cell line that was grown continuously for several hundred generations. When growing at the maximal rate in media containing 20% FBS (doubling time 18 h), the cells were fibroblastic and nearly devoid of pigment, but were capable of morphologic transition back to a pigmented, epithelioid form when cultured under low serum conditions. Evidence that these cells originated from RPE included specific immunolabeling with antibodies to cellular retinaldehyde binding protein and cytokeratin, negative GFAP immunoreactivity, and demonstration of avid phagocytosis of isolated rod outer segments by these cells. Partial characterization of choroidal cells eliminated the latter cells as possible contaminants which could have given rise to the cell line. The BPEI-1 cell line, and other rat RPE cell lines currently being developed from pigmented normal (LE, RCS rdy+p+) and retinal dystrophic (RCS p+) rats should facilitate biochemical and molecular biological approaches to study of RPE cell function in health and disease.

Significant clinical response of activated carbon adsorbed-peplomycin against esophageal cancer: a pilot study.

Activated carbon particle adsorbed-peplomycin (PEP-CH) was administered to three patients who had advanced esophageal cancer and its clinical usefulness was evaluated. The PEP-CH was injected endoscopically into the tumor or the adjacent normal esophageal tissue. Case 1 and case 3 were treated by topical injection of PEP-CH with or without surgery and case 2 was subjected to the PEP-CH treatment with radiation. The barium swallow and endoscopic examination exhibited a marked tumor reduction in all the patients at the end of the PEP-CH treatment. Although a marked clinical response was seen, case 1 died of postoperative complication. Two patients were capable of oral food intake after the treatment, which had been impossible before the treatment. There were no serious adverse side effects caused by the PEP-CH treatment in all the patients. PEP-CH should prove valuable as a new form of chemotherapy for the treatment of esophageal cancer patients.

Enhancement of cytotoxicity in mouse regional lymph nodes by local tissue injection of aclacinomycin A.

The effect of local tissue injection of activated carbon particle adsorbing aclacinomycin A (ACR-CH) on the cytotoxicity in popliteal, inguinal, paraaortic, and axillary lymph nodes was investigated in mice. Aclacinomycin (0.2 mg/kg), a potent antineoplastic drug was injected subcutaneously into the footpad of mice in the form of ACR-CH or as an ACR solution. After a single injection of ACR-CH, the regional nodal cytotoxic response against mouse YAC-1 lymphoma cells was markedly increased and sustained for 7-10 days. The immune response was also increased after ACR solution but to a much lesser extent. These effects were found in popliteal, inguinal, and paraaortic lymph nodal effector cells but not in the more remote axillary nodes. Absorption of adherence cells largely abrogated the cytotoxic response. These results suggest that ACR-CH did not impair but rather stimulated nodal immunoregulatory cells. Potentially ACR-CH may enhance immune responsiveness of regional lymph nodes after subcutaneous administration while concomitantly curtailing neoplastic growth in these same lymph nodes.

Toxicity of a new dosage format, cisplatin incorporated in lactic acid oligomer microspheres, in mice.

A new drug delivery system, cisplatin incorporated into lactic acid oligomer microspheres (CDDP-MS), was developed for the treatment of peritoneal carcinomatoses. We studied the acute toxicity and pathological effects of CDDP-MS injected intraperitoneally in mice. The 50% lethal dose was 23.8 mg/kg (21.3-26.7 mg/kg at 95% level of confidence), which was 1.76 times that of the cisplatin aqueous solution of 13.5 mg/kg (11.9-15.3 mg/kg at 95% level of confidence). The duration for the restoration of the body weight loss was prolonged when CDDP-MS at doses close to the 50% lethal dose was administered, as compared with the cisplatin aqueous solution at doses close to its 50% lethal dose. On autopsy there were no macroscopic or microscopic differences between the two dosage forms.

Lymph nodal vital staining with newer carbon particle suspensions compared with India ink: experimental and clinical observations.

CH40 and CH1500AA are newly prepared carbon suspensions which were examined as vital staining dyes for their usefulness in visualizing lymphatics at operation and to blacken lymph nodes. In mice, these carbon suspensions at 0.001 ml/g of body weight and India ink were injected subcutaneously into the footpad of the right hindpaw. Regional lymph nodes were visualized and were examined stereomicroscopically to determine how intensely these nodes blackened with carbon suspensions. Compared with India ink, CH40 and CH1500AA blackened the regional lymph nodes much faster and more vividly (1-8 min. after subcutaneous injection). As analyzed by centrifugal particle size distribution, CH40 and CH1500AA are narrowly distributed with a small particle size (150 and 167 nm, respectively, in mean diameter). By contrast, India ink is comprised of widely distributed and relatively large particles in suspension (mean diameter--254 nm). In 10 patients undergoing radical gastrectomy for treatment of stomach cancer, CH40 blackened 69% of regional lymph nodes with metastases (38 of 55) and 76% of those nodes without metastases (387 of 512).