A Maternal Risk Factor for Mother-to-Child HTLV-I Transmission: Viral Antigen-producing Capacities in Culture of Peripheral Blood and Breast Milk Cells

We examined the relationship between productivity of HTLV-I antigen-positive cells in cultured peripheral blood mononuclear cells (PBMC) and breast milk mononuclear cells (BMMC) and the incidence of mother-to-child transmission of HTLV-I. Among 61 cases of HTLV-I carrier mothers, 17 cases were revealed to produce large numbers of HTLV-I antigen-positive cells (high HTLV-I antigen-producing mothers) whose positive rate was 9.6% in PBMC and 10.2% in BMMC, while the remaining 44 cases produced small numbers of HTLV-I antigen-positive cells (low HTLV-I antigen-producing mothers) whose positive rate was 0.3% In PBMC and 0.5% in BMMC. The HTLV-I transmission rate among children born to the high HTLV-I antigen-producing mothers was 37.5% (6/16 children from 11 mothers), while that of the low HTLV-I antigen-producing mothers was 3.2% (1/31 children from 20 mothers). The transmission rate of HTLV-I was significantly different between high and low HTLV-I antigen-producing mothers (P<0.05). However, there was no positive relationship between anti-HTLV-I antibody titers and productivity of HTLV-I antigen-positive cells (P=0.11). These results suggested that mother-to-child transmission of HTLV-I might be influenced by a maternally determined factor to produce HTLV-I antigen-positive cells in PBMC and BMMC of HTLV-I carrier mothers.     

Allogeneic chimerism established with a mixture of low dose bone marrow cells and splenocytes in sublethally irradiated mice

BACKGROUND: Allogeneic chimerism has been established in graft-accepting recipients and the donor cells in the host may act in a major way to facilitate the induction of tolerance. In this study, we examined the effects of allogeneic chimerism after injecting donor bone marrow cells (BMCs) mixed with splenocytes (SPLCs) to the sublethally conditioned recipients. METHODS: In BALB/c(H-2(d)) to B6(H-2(b)) combination, B6 recipients were irradiated at 7.5 Gy and were injected a mixture of donor BMCs and SPLCs intravenously. On day 90 after injection, the degree of chimerism in peripheral blood lymphocytes (PBL) and in the splenocytes was checked by flow cytometry. RESULTS: In groups which were injected varying BMCs, when > 45 x 10(6) BMCs were injected into B6, a large percentage of donor cells were detected in PBL and in the spleen. In contrast, when < 30 x 10(6) BMCs were injected into B6, only a small percentage of donor cells were detected. In the groups which were injected 3 x 10(6) BMCs with varying SPLCs, when > 10 x 10(6) SPLCs were added, a large percentage of donor cells were detected in PBL and SPLCs, but a small percentage of donor cells were detected with the addition of < 3 x 10(6) SPLCs. A high percentage of chimeric mice showed donor specific tolerance in vitro, mixed lymphocyte responses, and in vivo, skin grafting. In contrast, only a small percentage of chimeric mice showed no donor specific tolerance by skin grafting. CONCLUSION: These findings suggested that even a low dose of BMCs can establish a state of allogeneic chimerism and donor specific tolerance if combined with SPLCs.     

Vitrectomy for diabetic cystoid macular edema

PURPOSE: We evaluated visual outcomes following vitrectomy for diabetic cystoid macular edema. METHODS: Visual outcomes and factors possibly influencing final visual acuity were assessed and documented retrospectively in 45 eyes of 40 patients, all of whom were followed up for at least 6 months postoperatively. RESULTS: Compared with the preoperative logarithm of the minimum angle of resolution (logMAR) visual acuity, final logMAR visual acuity improved 0.2 or more in 51% of the eyes, was unchanged in 47%, and decreased 0.2 or more in 2%. A final postoperative visual acuity of 0.5 or better was achieved in 38%. Preoperative visual acuity and the extent of the cystoid space on fluorescein angiography were significantly related to final visual acuity. A final postoperative visual acuity of 0.5 or better was noted in 8% of eyes with a preoperative visual acuity below 0.1, in 50% of eyes with a preoperative visual acuity of 0.1 or better, in 71% of eyes with a cystoid space smaller than 5 disc areas, and in 20% of eyes with a cystoid space of 5 disc areas or more. The state of the posterior vitreous membrane did not influence final visual acuity. There were no complications that decreased visual acuity. CONCLUSIONS: We conclude that diabetic cystoid macular edema is a good indication for vitrectomy, regardless of the state of the posterior vitreous membrane. A preoperative visual acuity of 0.1 or better and/or a cystoid space smaller than 5 disc areas may be indications for surgery aimed at achieving a final postoperative visual acuity of 0.5 or better.     

Learning/memory and drug dependence

We investigated the possible mechanisms of development of latent learning and morphine dependence by the methods of behavioral pharmacology and confirmed them by using mutant mice. The heterozygous mice for the tyrosine hydroxylase (TH) gene and for the cyclic AMP (cAMP) response element binding protein (CREB) binding protein (CBP) gene showed the impairment of latent learning in the water finding task, and these mice did not develop morphine dependence. The spatial learning and hippocampal long-term potentiation (LTP) were normal in the both mutants. TH heterozygous mice showed a reduction of high K(+)-evoked noradrenaline release in the frontal cortex measured by the microdialysis technique and of cAMP content in the brain. In conclusion, the results of mutant mice suggest that the alternation of catecholamine biosynthesis and cAMP signal pathways may play a key role in development of latent learning and morphine dependence, and they furthermore show that the expression of genes mediated by phosphorylated CREB may be involved in the development of latent learning and morphine dependence.     

New and better protocols for a short-term Caco-2 cell culture system

The aim of the present study was to develop new and better protocols for a short-term Caco-2 cell culture system for use in rapid screening of intestinal drug absorption. Caco-2 cells were cultured according to several protocols for short-term cell culture to obtain monolayers. The effects of serum (fetal bovine serum, FBS) in the culture medium and of the period of cell culture on the barrier function and transporter activities of the monolayers were examined. The barrier function was estimated both from the transepithelial electrical resistance (TEER) and the permeability of [(14)C]mannitol. Transporter activities were monitored by measuring the permeability of [(14)C]glycylsarcosine for oligopeptide transporter (PepT1) and of rhodamine 123 for P-glycoprotein (P-gp). Caco-2 monolayers obtained by 3-day culture in the BIOCOAT HTS Caco-2 Assay System, developed by Becton Dickinson Bioscience, showed much higher permeability to hydrophilic compounds, such as mannitol, compared with those obtained by the standard 21-day culture system, due to the leaky structure of cell junctions. The newly developed 3-day protocol, which includes 10% FBS in the culture medium during the first day of culture, markedly enhanced TEER and lowered mannitol permeability of the monolayers. This protocol allowed us to better determine the rank order of permeability of compounds, giving results equivalent to those in the 21-day culture system. The longer culture period gave tighter monolayers, and the maximum value of TEER was obtained with 5 days in culture. However, after 5 days in culture, the integrity of monolayers decreased gradually. The highest activities of transporters, PepT1 and P-gp, in monolayers were obtained at days 5 or 6 of culture by the new protocol with FBS-containing medium. These results indicate that by a simple modification of the short-term culture protocol, it is possible to obtain Caco-2 monolayers with better barrier properties and higher activity of transporters that are equivalent to those found in the 21-day Caco-2 culture system.     

The pharmacological characterization of attentional processes using a two-lever choice reaction time task in rats

Activating the noradrenergic and cholinergic systems is known to enhance attentional processes, while stimulating dopaminergic, serotonergic, and GABAergic systems suppresses them. The objective of the present study was to investigate the pharmacological characterization in the attentional processes of a two-lever choice reaction time (CRT) task using different centrally acting drugs. We designed seven parameters in this task: the correct response (CR) rate; error response rate; nonresponse (NR) rate; differential reinforcement of other behavior (DRO) responses; number of incorrect lever pressings during both the intertrial interval and DRO periods; the mean CRT of CR; and activity during 30 trials. The compounds produced different profiles at each dose. 1) Facilitative and disruptive effects on attentional processes occurred with changes in CRT alone. Scopolamine (0.1 mg/kg) and prazosin (0.3-1 mg/kg) prolonged the CRT, whereas methamphetamine (0.3 mg/kg) shortened the CRT. 2) Attentional deficits occurred with abnormal behavior showing premature response or perseverative behavior. Scopolamine (0.2-1 mg/kg), methamphetamine (3 mg/kg), delta(9)-tetrahydrocannabinol (10 mg/kg), and MK-801 (0.1-0.3 mg/kg) produced a marked increase in the number of total lever pressings. 3) Motor function deficits rather than attentional deficits occurred. 8-OH DPAT (1 mg/kg) and muscimol (1 mg/kg) produced a decrease in CR and an increase in NR with a marked decrease in activity and prolonged the CRT. Activating noradrenergic alpha(1) receptors was found to enhance the attentional processes, while blocking muscarinic receptors, alpha(1) receptors, and NMDA receptors, and stimulating cannabinoid receptors and the dopaminergic systems impaired the attentional processes in the two-lever CRT task.     

Vaticanol C, a novel resveratrol tetramer, inhibits cell growth through induction of apoptosis in colon cancer cell lines

A novel resveratrol tetramer, vaticanol C, isolated from the stem bark of Vatica rassak markedly suppressed cell growth through induction of apoptosis, which was characterized by nuclear changes and DNA ladder formation, in three different human colon cancer cell lines.     

Heart allograft tolerance without development of posttransplant cardiac allograft vasculopathy in chimerism-based, drug-induced tolerance

BACKGROUND: Recently, we have described a drug (cyclophosphamide [CP] plus busulfan [BU])-induced skin allograft tolerance in mice that can regularly overcome fully H-2-mismatched barriers. Using this method, we have investigated whether or not this regimen can prolong the survival of heart allografts and inhibit the development of posttransplant cardiac allograft vasculopathy (CAV). METHODS: The components of the method are intravenous administration of 1 x 108 allogeneic spleen cells on day 0, intraperitoneal injection of 200 mg/kg of CP and 30 mg/kg of BU on day 2, and intravenous injection of T cell-depleted 1 x 107 allogeneic bone marrow cells from the same strain of mice on day 3. Heart grafting was performed on day 28. Chimerism in peripheral blood was followed by flow cytometric analysis, and histological analysis was performed at various times after grafting. RESULTS: In a fully major histocompatability complex (MHC)-mismatched combination of B10.D2 (H-2d, IE+)-->B10 (H-2b, IE-), stable, multilineage-mixed chimerism was observed permanently. B10.D2 heart grafts were accepted permanently in a donor-specific manner, and posttransplant CAV did not develop. CONCLUSIONS: These results demonstrated that the drug-induced tolerance recently established by us can regularly induce a long-lasting heart allograft tolerance without development of CAV.     

A graft-versus-tumor effect in a patient with ependymoma who received an allogenic bone marrow transplant for therapy-related leukemia. Case report

Graft-versus-leukemia effect is an immune-mediated antitumor phenomenon associated with allogenic bone marrow transplants (BMTs) for hematological malignancies, and recent findings have indicated that a similar effect could occur in some solid tumors such as breast cancers. The authors report on a 42-year-old man with a recurrent ependymoma who received an allogenic BMT for therapy-related leukemia. After transplantation, the patient developed chronic graft-versus-host disease, which was controlled with steroid agents. Interestingly, the recurrent ependymoma regressed steadily over the next 21 months posttransplant, until the tumor became almost undetectable on magnetic resonance images. This case indicates that the graft-versus-tumor effect, mediated by cytotoxic T cells, may be able to target intraparenchymal neuroepithelial tumors, despite the brain's generally recognized status as an immunoprivileged organ.     

Preclinical combination chemotherapy of nedaplatin with gemcitabine against gemcitabine-refractory human lung cancer

This study determined the selective cytotoxicity of eight coumarin compounds to human renal carcinoma cells, relative to non-carcinoma proximal tubular cells. Selectivity cytotoxicity was observed following exposure to 6-nitro-7-hydroxycoumarin (6-NO(2)-7-OHC) and 7,8-dihydroxycoumarin (7,8-OHC). 6-NO(2)-7-OHC induced cytotoxicity was irreversible in both cell lines, unlike 7,8-OHC, which was reversible in the carcinoma cells only. Mobility shift and BrdU incorporation assays showed that both compounds did not intercalate DNA but had a concentration-dependent inhibitory effect on its synthesis. All coumarins studied were found to be non-mutagenic using the standard Ames test. These results would suggest that 6-NO(2)-7-OHC and 7,8-OHC might have a therapeutic role to play in the treatment of renal cell carcinoma.