Choroidal vascular repair following orange dye laser photocoagulation

In order to evaluate the effect of laser photocoagulation on choroidal vessels, moderate laser burns were performed on monkey fundi with a dye orange beam (595 nm) at various intervals for a period of 60 days. After photocoagulation, choroidal vascular casts were prepared by injection of Mercox resin into the carotid arteries, and then observed by scanning electron microscopy. Immediately after photocoagulation, filling defects of the choriocapillaris and medium-sized choroidal vessels were seen in all lesions. By three to five days, restoration of the choroidal microcirculation in the laser lesions had begun. At seven to ten days, filling defects of the choriocapillaris had gradually become undemarcated. By 2 weeks, the sites of the former filling defects were occupied by a loose network of capillaries. At 60 days, the laser lesions had been entirely replaced by newly formed choriocapillaris, composed of narrower lumina and showing a more irregular lobular pattern than normal choriocapillaris.     

Direct evidence for the up‐regulation of Vps34 regulated by PKCγ during short‐term treatment with morphine

In this study, we investigated whether PKCγ could be associated with functional changes of vacuolar protein sorting 34 (Vps34) during morphine treatment using primary cultures of cerebral cortical neurons from mice. The immunoprecipitation analysis showed that p‐PKCγ and Vps34 are present together in molecular complexes. The treatment with morphine increases PKCγ and Vps34 levels. Phosphorylation of PKCγ increased Vps34 level. The inhibition of morphine‐induced increase in PKCγ phosphorylation reduced Vps34 level. These results indicates that opioid receptor activation increases PKCγ phosphorylation in the neurons and, in turn, upregulates Vps34 during short‐term treatment with neurons. Synapse 63:365–368, 2009. © 2009 Wiley‐Liss, Inc.     

Anti-cancer therapy with valine-depleted amino acid imbalance solution

For the purpose of developing amino acid imbalance solution applicable to cancer treatment, we prepared seven kinds of amino acid imbalance solutions based on a 10% balanced amino acid solution and investigated the anti-tumor effects of each solution. The administration of valine-depleted amino acid solution for 8 days at a daily dose of 53 ml/rat (79.5 kcal/rat) resulted in the most significant inhibitory effects on the growth of hepatoma (AH109A) and mammary tumors (MRMT-1), the rate being 82.8% and 90.8%, respectively. Side effects observed were inhibition of increases in host body weight, weight loss of the spleen and thymus, loss of hair, and a decrease in the amounts of total plasma protein and albumin. When the daily dosage of valine-depleted amino acid solution was reduced to 40 ml/rat (58.3 kcal/rat), anti-tumor effects were still noticed, while side effects were abated. These findings indicate that side effects accompanying the use of this solution can be alleviated by controlling the ingredients of the solution as well as the amount administered. It is thus suggested that valine-depleted amino acid imbalance solution is a valuable tool in the treatment of cancer.     

Breast masses with mixed cystic-solid sonographic appearance

Retrospective analysis was performed for 56 breast masses with mixed cystic and solid sonographic patterns encountered in the last 5 years at Keio University Hospital, with the objective of elucidating their significance. The lesions were classified into two major groups: tumor with cyst (TWC—solid mass with cystic component) and intracystic tumor (ICT—cystic mass with solid component). According to the pathological diagnosis, 57% were benign and 43% were malignant. Fifty eight percent of malignant lesions were shown to have a TWC pattern and 42% an ICT pattern. Among benign lesions, 66% were shown to be TWC and 34% ICT. In malignant tumors, 96% of the cases showed irregular shape and heterogeneous internal content. Even in benign lesions, a high incidence of irregular shape and rough border was found, although the predominant internal echo texture was homogeneous, and threedimensional (3-D) contour was not clear. In conclusion, we observed that in the TWC group, the lack of a defined 3-D contour is the most important criterion, and tumors with multiples cysts tend to be benign. © 1993 John Wiley & Sons, Inc.     

Nateglinide and mitiglinide, but not sulfonylureas, induce insulin secretion through a mechanism mediated by calcium release from endoplasmic reticulum

Nateglinide and mitiglinide (glinides) are characterized as rapid-onset and short-acting insulinotropic agents. Although both compounds do not have a sulfonylurea structure, it has been postulated that insulin secretion is preceded by their binding to Kir6.2/SUR1 complex, and a mechanism of insulin secretion of glinides has been accounted for by this pathway. However, we hypothesized the involvement of additional mechanisms of insulin secretion enhanced by glinides, and we analyzed the pattern of time course of insulin secretion from MIN6 cells with the existence of agents that have specific pharmacologic actions. Dose-dependent effects of tolbutamide, glibenclamide, nateglinide, and mitiglinide were observed. Insulin secretion induced by 3 microM tolbutamide and 1 nM glibenclamide was completely inhibited by 10 microM diazoxide and 3 microM verapamil, although the latter half-component of insulin secretion profile induced by 3 microM nateglinide or 30 nM mitiglinide remained with the existence of those agents. Glinides enhanced insulin secretion even in Ca2+-depleted medium, and its pattern of secretion was same as the pattern with existence of verapamil. The latter half was suppressed by 1 microM dantrolene, and concomitant addition of verapamil and dantrolene completely suppressed the entire pattern of insulin secretion enhanced by nateglinide. Thus, we conclude that glinide action is demonstrated through two pathways, dependently and independently, from the pathway through K(ATP) channels. We also demonstrated that the latter pathway involves the intracellular calcium release from endoplasmic reticulum via ryanodine receptor activation.     

Adenosine abolishes MTX-induced suppression of osteoclastogenesis and inflammatory bone destruction in adjuvant-induced arthritis

Methotrexate (MTX) is widely utilized for the treatment of patients with rheumatoid arthritis (RA); however, recent observation of the MTX-resistant patients proposed some difficulty in MTX-dependent therapeutic approach for RA. To access cellular events related to MTX resistance in RA in respect to inflammatory bone destruction, we investigated on an involvement of the potent inflammatory mediator adenosine in the regulation of osteoclastogenesis and inflammatory bone destruction. In rats with adjuvant-induced arthritis (AA rats), MTX efficiently suppressed bone destruction when it was administrated within 3 days after adjuvant injection, while it could not suppress inflammatory bone destruction if MTX was injected at the time of onset of inflammation (at day 10 after adjuvant injection). Time-course change in the level of plasma adenosine of AA rats was estimated by use of high-performance liquid chromatography and elucidated that adenosine level was markedly elevated till 10 days after adjuvant injection. In vitro bone marrow culture system for evaluating osteoclastogenesis, MTX markedly suppressed osteoclastogenesis in a stromal cell-dependent manner. This MTX-induced suppression of osteoclastogenesis was abrogated by the addition of adenosine. MTX suppressed the expression of mRNA for the receptor activator NF-κB ligand (RANKL), but it did not suppress the expression of osteoprotegerin (OPG). The addition of MTX and adenosine together markedly suppressed the level of OPG expression. Abolishment of MTX action by adenosine was significantly blocked by MRS1754, a highly selective antagonist for the A(2b) adenosine receptor (A(2b)AR), but not by caffeine, an antagonist for A?, A(2a), A? AR (A?AR, A(2a)AR, and A?AR), which suggests that adenosine acts through A(2b)AR. Immunohistochemical studies showed abundant expression of A(2b)AR in cells localized in the bone-bone marrow boundary of the distal tibia in AA rats but not in control rats. When adenosine was injected in the ankle joints of MTX-treated AA rats, the suppressive effects of MTX on bone destruction was abolished. The current data therefore suggest that upregulation of adenosine production abolished the suppressive effect of MTX on osteoclastic bone destruction. Involvement of the adenosine-A(2b)AR system may explain MTX resistance in RA.     

Serologically HLA-DR—Mismatched Unrelated Donors Might Provide a Valuable Alternative in Allogeneic Transplantation: Experience from a Single Japanese Institution

To clarify the clinical significance of a serologic HLA-DR mismatch after unrelated-donor transplantation, we evaluated for hematologic malignancies 123 cases of unrelated bone marrow transplantation carried out in a single institution between 1995 and 2004. Of the patients in these cases, 12 were serologically mismatched at the single HLA-DR locus. Eighty-two patients who received HLA-matched transplantations were used as controls. Conditioning consisted of a conventional total body irradiation-based regimen or a fludarabine-based reduced-intensity regimen. Prophylaxis for graft-versus-host disease (GVHD) consisted of tacrolimus plus short-term methotrexate. Graft failure did not develop. With a median follow-up of 42 months (range, 11-99 months), rates of overall survival, nonrelapse mortality, and relapse at 4 years were 63%, 38%, and 0%, respectively, all of which were comparable with those after HLA-matched transplantation. The frequency of acute GVHD of grades II to IV was 75%, significantly higher than after HLA-matched transplantation (42%, P = .046), and there was a trend toward an increased incidence of acute GVHD of grades III to IV after serologically HLA-DR-mismatched unrelated transplantation (27% versus 10%, P = .093). Chronic GVHD developed in 4 of 11 evaluable patients, an incidence comparable with that after HLA-matched transplantation. In summary, serologically HLA-DR-mismatched unrelated transplantation is feasible and might be an acceptable alternative for the Japanese population, although the higher incidence of acute GVHD is notable.