A synthetic retinoic acid receptor γ antagonist (7C)-loaded nanoparticle enhances bone morphogenetic protein-induced bone regeneration in a rat spinal fusion model

BACKGROUND CONTEXT

Bone morphogenetic proteins (BMPs) have potent osteoinductivity and have been applied clinically for challenging musculoskeletal conditions. However, the supraphysiological doses of BMPs used in clinical settings cause various side effects that prevent widespread use, and therefore the BMP dosage needs to be reduced.

PURPOSE

To address this problem, we synthesized 7C, a retinoic acid receptor γ antagonist-loaded nanoparticle (NP), and investigated its potential application in BMP-based bone regeneration therapy using a rat spinal fusion model.

STUDY DESIGN

An experimental animal study.

METHODS

Fifty-three male 8-week-old Sprague-Dawley rats underwent posterolateral spinal fusion and were divided into the following five treatment groups: (1) no recombinant human (rh)BMP-2 and blank-NP (Control), (2) no rhBMP-2 and 1 μg 7C-NP (7C group), (3) low-dose rhBMP-2 (0.5 μg) and 1 μg blank-NP (L-BMP group), (4) low-dose rhBMP-2 (0.5 μg) and 1 μg 7C-NP (L-BMP + 7C group), and (5) high-dose rhBMP-2 (5.0 μg) and 1 μg blank-NP (H-BMP group). Micro-computed tomography and histologic analysis were performed 2 and 6 weeks after the surgery.

RESULTS

The spinal fusion rates of the Control and 7C groups were both 0%, and those of the L-BMP, L-BMP + 7C, and H-BMP groups were 55.6%, 94.4%, and 100%, respectively. The L-BMP + 7C group markedly promoted cartilaginous tissue formation during BMP-induced endochondral bone formation that resulted in a significantly better spinal fusion rate and bone formation than in the L-BMP group. Although spinal fusion was slower in the L-BMP + 7C group, the L-BMP + 7C group formed a spinal fusion mass with better bone quality than the spinal fusion mass in the H-BMP group.

CONCLUSIONS

The combined use of 7C-NP with rhBMP-2 in a rat posterolateral lumbar fusion model increased spinal fusion rate and new bone volume without deteriorating the quality of newly formed bone.

CLINICAL SIGNIFICANCE

7C-NP potentiates BMP-2-induced bone regeneration and has the potential for efficient bone regeneration with low-dose BMP-2, which can reduce the dose-dependent side effects of BMP-2 in clinical settings.

Evaluation of Choroidal Structure in Type 1 Macular Neovascularization Using Different Optical Coherence Tomography Analyses: Scale Bar and Binarization

BACKGROUND

Macular neovascularization (MNV) has been evaluated by optical coherence tomography (OCT) imaging using various approaches. However, few studies have examined their differences. This study analyzed type 1 MNV with a combination of two approaches: scale bar and binarization.

METHODS

We enrolled 84 patients with untreated type 1 MNV. We measured choroidal parameters using a scale bar and defined the ratios of superficial choroidal thickness to choroidal vessel diameter (SV ratios). We also used binarization and calculated the ratios of the luminal to the choroidal area (LC ratios) in two directions (horizontal and vertical).

RESULTS

Fifty-one patients (61%) were classified as having polyps. SV ratios in the group with polyps were significantly lower than in the group without (p < 0.001). The receiver operating characteristic (ROC) curve showed that the SV ratio was predictive of polyps (AUC 0.733, 95% CI: 0.621-0.844). In patients without polyps, horizontal LC ratios were significantly higher in a subgroup with subretinal fluid than in those without (p = 0.047). The ROC curve showed that the LC ratio was predictive of subretinal fluid (AUC 0.722, 95% CI: 0.517-0.926).

CONCLUSION

The SV ratio reflects the MNV disease type, whereas the LC ratio reflects MNV disease activity. Establishing cut-off values for each ratio may be useful for MNV diagnosis.

En-Face Optical Coherence Tomography Is Useful for Assessing Striated Lesions in Angioid Streaks: A Case Report

Angioid streaks are mainly characterized by radially striated lesions around the optical disc and result in severe vision loss when choroidal neovascularization (CNV) develops at the macula. The prediction of visual prognosis in cases with angioid streaks remains an unsolved problem. In this study, we report the usefulness of en-face optical coherence tomography (OCT) to assess the bilateral striated lesions in angioid streaks. A 59-year-old female who was previously diagnosed with angioid streaks complained of decreased visual acuity in her left eye. However, on en-face OCT, the striated lesions in the right eye with better vision were shown as thicker continuous lesions than those in the left eye. Twenty-four months after the initial visit, her right visual acuity was worse than her left. En-face OCT showed fine-striated lesions extending from those thicker lesions to the macular area in the right eye. The thicker striated lesions observed at the initial visit may be a risk factor for future CNV development and vision loss. The evaluation of lesion size using en-face OCT may be useful for predicting the visual prognosis in angioid streaks.

Development of an Eccentric Macular Hole Followed by Reopening of the Original Macular Hole as a Long-term Sequelae of Internal Limiting Membrane Peeling and Focal Laser Photocoagulation: A Case Report

A macular hole (MH) is a widely known disease among ophthalmologists. Vitrectomy with internal limiting membrane (ILM) peeling is a standard technique for full-thickness MHs. However, the recurrence of MHs is sometimes seen. In addition, an eccentric MH is known to rarely occur after vitrectomy. An eccentric MH has been considered to require no therapeutic intervention because of its lack of increase in size. This study reports a case of two MHs (a recurrent MH and an enlarged eccentric MH) developed after laser photocoagulation around the injured retina caused by ILM peeling at the initial surgery. A 56-year-old woman presented with an idiopathic MH in her left eye and best-corrected visual acuity (BCVA) was decreased to 20/80. She underwent phacoemulsification and vitrectomy combined with posterior hyaloid removal, ILM peeling, and 20% sulfur hexafluoride gas tamponade.  During the ILM peeling, we performed laser photocoagulation around the injured retina within the arcade. The MH was successfully closed and her BCVA was improved to 20/20 one month after surgery. Eight months after surgery, an eccentric MH occurred next to the photocoagulation spots. However, her BCVA remained 20/20; thus, we just followed up on her eye. Six years after surgery, her BCVA was decreased to 20/200. The eccentric MH increased in size and the original MH re-opened. The second vitrectomy was performed, but ILM had been already peeled within the arcade during the previous surgery and a usable sufficient size of ILM which could be auto-transplanted to the holes was not obtained. Thus, free flaps of the posterior lens capsule were harvested and placed within each hole. Two holes were successfully closed and her BCVA improved to 10/20 at three months after the surgery. Laser photocoagulation around the injured retina derived from ILM peeling may be a risk for recurrent MHs. .

Sarcoidosis presenting as optic neuritis with vision loss

Neurosarcoidosis is a rare complication of sarcoidosis and unusually presents as optic neuritis. We present the case of a 51-year-old man who complained of right vision loss. Brain magnetic resonance imaging showed asymmetrical enlargement of the right optic nerve. Chest computed tomography detected mediastinal and hilar lymphadenopathy. There were cutaneous nodules on the back. Biopsy of the mediastinal lymph node by endobronchial ultrasound-guided transbronchial needle aspiration and the skin showed noncaseating granulomas consistent with sarcoidosis. Serum angiotensin-converting enzyme level was elevated (34.2 IU/L) (normal: 8.3-21.4 IU/L). Based on these findings, he was diagnosed as neurosarcoidosis with optic neuritis. He was started on 1000-mg/day methylprednisolone intravenously for 3 days, followed by oral 50-mg/day prednisolone, which was gradually tapered for 8 weeks. Thereafter, the skin nodules and lymphadenopathy decreased and the right vision partially improved. Based on this rare case, sarcoidosis should be considered as a differential diagnosis in cases of optic neuritis.

Alteration of plasma von Willebrand factor in the treatment of retinal vein occlusion with cystoid macular edema

Retinal vein occlusion (RVO) is a major retinal disease caused by venous thrombosis. Although several studies have proposed an association between venous thrombosis and von Willebrand factor (VWF), the association between RVO and VWF remains unclear. We aimed to investigate the association between RVO and VWF and the alteration of VWF levels under anti-vascular endothelial growth factor (VEGF) treatment. We enrolled 55 patients with RVO involved cystoid macular edema. They received intravitreal injection of anti-VEGF drugs, either ranibizumab or aflibercept. We examined the clinical data and measured plasma VWF antigen and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activity to identify variabilities during treatment. At baseline, there was no significant difference between the RVO group and age-matched controls in both VWF antigen and ADAMTS13 activity levels, but ADAMTS13 activity was significantly lower in central RVO than in branch RVO (P = 0.015). In branch RVO, VWF antigen was negatively correlated with central choroidal thickness (r = −0.51, P < 0.001). In branch RVO after anti-VEGF treatment, VWF antigen levels decreased significantly from 134% at baseline to 109% at 1 day (P = 0.002) and 107% at 1 month (P = 0.030) after treatment. In contrast, ADAMTS13 activity showed no significant difference during this period. In branch RVO at 1 month after treatment, VWF antigen was negatively correlated with central choroidal thickness (r = −0.47, P = 0.001). Our findings suggest an association between VWF and central choroidal thickness in patients with branch RVO, thus the measurement of VWF may be useful for evaluating disease activity and prognosis.

Effects of rhBMP-2-loaded hydroxyapatite granules/beta-tricalcium phosphate hydrogel (HA/β-TCP/hydrogel) composite on a rat model of caudal intervertebral fusion

The effects and inflammation-related side effects of bone morphogenetic protein (BMP)-2 on posterior lumbar interbody fusion are controversial. One of the potential causes for the inconsistent results is the uncontrolled release of BMP-2 from the collagen carrier. Therefore, BMP delivery systems that support effective bone regeneration while attenuating the side effects are strongly sought for. We developed NOVOSIS putty (NP), a novel composite material of hydroxyapatite (HA), beta-tricalcium phosphate (β-TCP)/hydrogel, and BMP-2, which can sustainably release BMP-2 over 2 weeks. This study was aimed at comparing the effects and side effects of NP and collagen sponge (CS) containing BMP-2 using a rat caudal intervertebral fusion model. The fusion rates of NP with low and high doses of BMP-2 were significantly higher than those of an iliac bone (IB) graft, but those of CS with low and high doses of BMP-2 were not different from those of the IB graft. Furthermore, the incidences of ectopic bone formation and soft tissue swelling were significantly lower in the NP group than in the CS group. The HA/β-TCP/hydrogel carrier enabled superior bone induction with low-dose BMP-2 and decreased the incidence of side effects caused by high-dose BMP-2 vis-à-vis the collagen carrier.

Prostaglandin EP4 Selective Agonist AKDS001 Enhances New Bone Formation by Minimodeling in a Rat Heterotopic Xenograft Model of Human Bone

To enhance bone regeneration, the use of bone morphogenetic protein (BMP)-2 is an attractive option. Unfortunately, the dose-dependent side effects prevent its widespread use. Therefore, a novel osteogenic agent using a different mechanism of action than BMP-2 is highly desirable. Previous reports demonstrated that prostaglandin E2 receptor 4 (EP4) agonists have potent osteogenic effects on non-human cells and are one of the potential alternatives for BMP-2. Here, we investigated the effects of an EP4 agonist (AKDS001) on human cells with a rat heterotopic xenograft model of human bone. Bone formation in the xenograft model was significantly enhanced by AKDS001 treatment. Histomorphometric analysis showed that the mode of bone formation by AKDS001 was minimodeling rather than remodeling. In cultured human mesenchymal stem cells, AKDS001 enhanced osteogenic differentiation and mineralization via the cAMP/PKA pathway. In cultured human preosteoclasts, AKDS001 suppressed bone resorption by inhibiting differentiation into mature osteoclasts. Thus, we conclude that AKDS001 can enhance bone formation in grafted autogenous bone by minimodeling while maintaining the volume of grafted bone. The combined use of an EP4 agonist and autogenous bone grafting may be a novel treatment option to enhance bone regeneration. However, we should be careful in interpreting the results because male xenografts were implanted in male rats in the present study. It remains to be seen whether females can benefit from the positive effects of AKDS001 MS by using female xenografts implanted in female rats in clinically relevant animal models.

Selective Retinoic Acid Receptor γ Antagonist 7C is a Potent Enhancer of BMP-Induced Ectopic Endochondral Bone Formation

Bone morphogenetic proteins (BMPs) have been clinically applied for induction of bone formation in musculoskeletal disorders such as critical-sized bone defects, nonunions, and spinal fusion surgeries. However, the use of supraphysiological doses of BMP caused adverse events, which were sometimes life-threatening. Therefore, safer treatment strategies for bone regeneration have been sought for decades. Systemic administration of a potent selective antagonist of retinoic acid nuclear receptor gamma (RARγ) (7C) stimulated BMP-induced ectopic bone formation. In this study, we developed 7C-loaded poly lactic nanoparticles (7C-NPs) and examined whether local application of 7C enhances BMP-induced bone regeneration. The collagen sponge discs that absorbed recombinant human (rh) BMP-2 were implanted into the dorsal fascia of young adult mice to induce ectopic bone. The combination of rhBMP-2 and 7C-NP markedly increased the total bone volume and thickness of the bone shell of the ectopic bone in a dose-dependent manner compared to those with rhBMP-2 only. 7C stimulated sulfated proteoglycan production, expression of chondrogenic marker genes, and Sox9 reporter activity in both chondrogenic cells and MSCs. The findings suggest that selective RARγ antagonist 7C or the related compounds potentiate the bone inductive ability of rhBMP-2, as well as support any future research to improve the BMP-2 based bone regeneration procedures in a safe and efficient manner.

Analysis focusing on plasma von Willebrand factor in pachychoroid neovasculopathy and age-related macular degeneration

Pachychoroid neovasculopathy (PNV) is a new concept of macular disorder. Some cases diagnosed as age-related macular degeneration (AMD) have been re-diagnosed as PNV. However, the biological features of PNV are still uncertain. The purpose of this study was to compare PNV and AMD by analyses focusing on von Willebrand factor (VWF) and complement factor H (CFH). Ninety-seven patients who were previously diagnosed with treatment naïve AMD were enrolled in this study. They were re-classified as either PNV or AMD based on the clinical criteria and 33 patients were classified as PNV and 64 patients as AMD. We examined the clinical data, analyzed VWF multimer and two genetic polymorphisms (I62V and Y402H) in the CFH. PNV group was significantly younger than AMD group (P = 0.001). In both I62V and Y402H, there were no significant differences between PNV and AMD while the recessive homozygous (AA) was found only in PNV group in I62V. The presence of unusually large VWF multimers (UL-VWFMs) and subretinal hemorrhages were significantly higher in PNV than in AMD (P = 0.045, P = 0.020, respectively). Thus, the residual UL-VWFMs may result in platelet thrombosis and hemorrhages in the choriocapillaris of PNV. In conclusion, our results suggest the biological differences between PNV and AMD.

Clinical implications of pachyvessels in polypoidal choroidal vasculopathy

Background

Polypoidal choroidal vasculopathy (PCV) is one of the disorders within the pachychoroid spectrum diseases. The presence of pachyvessels is one of the characteristics of pachychoroid disorders. However, the relationship between the presence of pachyvessels and the clinical characteristics of PCV eyes has not been determined. The purpose of this study was to determine the relationship between the presence of choroidal pachyvessels and the clinical characteristics of eyes with PCV.

Methods

The medical records of patients who were diagnosed with PCV and were treatment-naïve were reviewed. Fluorescein and indocyanine green angiography, fundus photography, spectral domain optical coherence tomography (SD-OCT), and enhanced depth imaging OCT (EDI-OCT) were used to obtain images of the choroid. The presence of pathologically dilated outer choroidal vessels, pachyvessels, was determined by ICGA images. These pachyvessels were confirmed to correspond with the large choroidal vessels in the EDI OCT images. The PCV eyes were divided into two groups based on the presence or absence of pachyvessels and clinical features and subfoveal choroidal thickness (SFCT) were evaluated between the two groups.

Results

Eighty-six eyes of 84 patients with PCV were evaluated. Pachyvessels were detected in 48 eyes (55.8%). The mean SFCT was 203.9 ± 83.9 μm in all 86 eyes, and it was significantly thinner in eyes with pachyvessels (+) than without pachyvessels (−) (183.2 ± 58.4 μm vs 230.2 ± 103.1 μm; P = 0.01). The differences in the incidence of subretinal fluid, pigment epithelial detachments, and hemorrhages between the two groups were not significant. However, the PCV eyes in pachyvessels (+) group with hemorrhage had the thinnest choroid (P = 0.047). The choroidal features of the fellow eyes were similar to those of the PCV affected eyes, that is, the fellow eyes in pachyvessels (+) group had pachyvessels and the fellow eyes in pachyvessels (−) group did not have pachyvessels.

Conclusions

Pachyvessels were presented 55.8% in eyes with PCV, and these eyes had the thin SFCT. The presence of pachyvessels and attenuation of the inner choroid were probably due to the pathological changes in the eyes with PCV.

Effects of concentration of amyloid β (Aβ) on viability of cultured retinal pigment epithelial cells

Background

Amyloid beta (Aβ) is a constituent of drusen that is a common sign of age-related macular degeneration (AMD). The purpose of this study was to investigate the effect of Aβ on human retinal pigment epithelial (RPE) cells in culture.

Methods

Cells from a human RPE cell line (ARPE-19) were exposed to 0 to 25 μM of Aβ 1–40 for 48 h, and the number of living cells was determined by WST-8 cleavage. Replicative DNA synthesis was measured by the incorporation of 5′-bromo-2′-deoxyuridine. The cell death pathway was investigated by the WST-8 cleavage assay after the addition of caspase-9 inhibitor, an anti-apoptotic factor. Real-time qRT-PCR was performed using Aβ-exposed cellular RNA to determine the level of vascular endothelial growth factor (VEGF)-A and pigment epithelium derived factor (PEDF). To determine the effect of receptor-for-advanced glycation end products (RAGE), the siRNA for RAGE was inserted into ARPE-19 treated with Aβ, and the levels of expression of VEGF-A and PEDF were determined.

Results

The number of living ARPE-19 cells was increased by exposure to 5 μM Aβ but was decreased by exposure to 25 μM of Aβ. Replicative DNA synthesis by ARPE-19 cells exposed to 25 μM of Aβ was significantly decreased indicating that 25 μM of Aβ inhibited cell proliferation. Real-time RT-PCR showed that the level of the mRNA of PEDF was increased by exposure to 5 μM Aβ, and the levels of the mRNAs of PEDF and VEGF-A were also increased by exposure to 25 μM Aβ. The addition of an inhibitor of caspase-9 blocked the decrease the number of ARPE-19 cells exposed to 25 μM Aβ. Exposure to si-RAGE attenuated the increase of VEGF-A and PEDF mRNA expression in ARPE-19 exposed to Aβ.

Conclusions

Exposure of ARPE-19 cells to low concentrations of Aβ increases the level of PEDF which then inhibits the apoptosis of ARPE-19 cells leading to RPE cell proliferation. Exposure to high concentrations of Aβ induces RPE cell death and enhances the expression of the mRNA of VEGF-A in RPE cells. The Aβ-RAGE pathway may lead to the expression VEGF-A and PEDF in RPE cells. These results suggest that Aβ is strongly related to the pathogenesis of choroidal neovascularization.

Case of progressive hyperopia due to flattening of cornea

Purpose

To report a case that had a progressive decrease in the visual acuity caused by a progressive increase in the hyperopia due to a flattening of the cornea.

Observations

A 50-year-old woman complained of decreased vision in both eyes. Her decimal best-corrected visual acuity was 1.2 in the right and 0.5 in the left eyes, and the refractive error (spherical equivalent) was +3.75 diopters (D) for the right eye and +6.5 D for the left eye. Slit-lamp examinations showed clear corneas but Descemet‘s folds and fine pigmentations and opacities were present beneath the corneal epithelium in both eyes. Analysis of the corneal shape by anterior segment optical coherence tomography showed that the corneas were flattened, and the corneal refractive power was decreased in both eyes. The large values of the higher-order aberration in the cornea and total eye displayed bilateral irregular astigmatism. She obtained good vision by wearing hard contact lenses but her refractive power continued to decrease for at least 1 year.

Conclusions

and Importance: We report a rare case of progressive hyperopia and irregular astigmatism due to a flattening of the cornea. Folds were present in Descemet‘s membrane but the cornea was not edematous.

A prospective phase II study of combined androgen blockade in patients with androgen receptor-positive metastatic or locally advanced unresectable salivary gland carcinoma

Background

There is no standard first-line chemotherapy for recurrent/metastatic (RM) or unresectable locally advanced (LA) salivary gland carcinoma (SGC).

Patients and methods

We conducted a single institution, open-label, single arm, phase II trial of combined androgen blockade (CAB) for androgen receptor (AR)-positive SGC. Leuprorelin acetate was administered subcutaneously at a dose of 3.75 mg every 4 weeks. Bicalutamide was administered orally at a daily dose of 80 mg. Patients were treated until progressive disease or unacceptable toxicities.

Results

Thirty-six eligible patients were enrolled. Thirty-three patients had RM disease and three patients had LA disease. The pathological diagnoses were salivary duct carcinoma (34 patients, 94%) and adenocarcinoma, NOS (two patients, 6%). The best overall response rate was 41.7% [n = 15, 95% confidence interval (CI), 25.5%-59.2%], the clinical benefit rate was 75.0% (n = 27, 95% CI, 57.8%-87.9%). The median progression-free survival was 8.8 months (95% CI, 6.3-12.3 months) and the median overall survival was 30.5 months (95% CI, 16.8 months to not reached). Additional analyses between treatment outcomes and clinicopathological factors or biomarkers including AR positivity, human epidermal growth factor receptor 2 status, and its complex downstream signaling pathway gene mutations showed no statistically significant differences. Elevated grade 3 liver transaminases and increased serum creatinine were reported in two patients, respectively. Discontinuation of leuprorelin acetate or bicalutamide due to adverse event occurred in one patient.

Conclusion

This study suggests that CAB has equivalent efficacy and less toxicity for patients with AR-positive RM or unresectable LA SGC compared with conventional chemotherapy, which warrants further study.

Clinical Trial Registration

UMIN-CTR (http://www.umin.ac.jp/ctr/index-j.htm), identification number: UMIN000005703.

Artificial Conditioner for Stored Organs

We have developed an artificial organ conditioning system in order not only to condition but also evaluate the viability for transplant graft of kidneys which have been stored for a long time and damaged by warm ischaemia following cardiac arrest. The conditioning system consisted of an artificial lung, a roller pump, an organ chamber and perfusate. The perfusate was prepared with electrolytes, fluorocarbon, amino acid, glucose, an oxygen scavenger and so on. Conditioning was performed by continuous perfusion under mild hypothermia at 24° C. Mildly damaged kidneys (0 and 30 minutes warm ischaemia rabbit kidneys) were well conditioned but severely damaged kidneys failed to produce urination. Our device successfully exposed the viability of stored kidneys and the successful conditioning of damaged kidneys due to warm ischaemia avoiding transplantation. By establishing our method, the harvesting of kidneys following cardiac arrest will be feasible.

Statins decrease vascular epithelial growth factor expression via down-regulation of receptor for advanced glycation end-products

Aims

Statins, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase, possess pleiotropic effects that have been extended to modulation of various cellular behaviors. This study aimed to examine whether statins modulate vascular endothelial growth factor A (VEGF-A) expression in human retinal pigment epithelium (RPE) cells.

Main methods

Human RPE cells (h1RPE7), damaged by hydroquinone (HQ) + advanced glycation endproducts (AGE) in an in vitro AMD model, were treated with atorvastatin or lovastatin for 24 h. The expression of VEGF-A and receptor for AGE (RAGE) was evaluated by real-time RT-PCR. VEGF-A secretion was measured by ELISA. To investigate the impact of RAGE on VEGF-A expression, small interfering RNA (siRNA) for RAGE (siRAGE) was introduced into h1RPE7 cells and VEGF-A expression was measured by real-time RT-PCR. Deletions of VEGF-A and RAGE promoters were performed and transcriptional activities were measured after the addition of statins to HQ + AGE-damaged RPE cells.

Key findings

The mRNA levels of VEGF-A and RAGE and the levels of VEGF-A in the culture medium were increased by HQ + AGE. Both atorvastatin and lovastatin attenuated HQ + AGE-induced VEGF-A and RAGE expression. These statins also decreased VEGF-A levels in the culture medium. RNA interference of RAGE attenuated the up-regulation of VEGF-A in the HQ + AGE treated cells. The deletion analysis demonstrated that these statins attenuated RAGE promoter activation in HQ + AGE-damaged RPE cells.

Significance

Statins attenuated HQ + AGE-induced VEGF expression by decreasing RAGE expression. As VEGF is an important factor in developing wet AMD, statins could decrease the risk of wet-type AMD and be used as preventive medicines.

Constitutively active ABL family kinases, TEL/ABL and TEL/ARG, harbor distinct leukemogenic activities in vivo

ABL (ABL1) and ARG (ABL2) are highly homologous to each other in overall domain structure and amino-acid sequence, with the exception of their C termini. As with ABL, translocations that fuse ARG to ETV6/TEL have been identified in patients with leukemia. To assess the in vivo leukemogenic activity of constitutively active ABL and ARG, we generated a bone marrow (BM) transplantation model using the chimeric forms TEL/ABL and TEL/ARG, which have comparable kinase activities. TEL/ABL rapidly induced fatal myeloid leukemia in recipient mice, whereas recipients of TEL/ARG-transduced cells did not develop myeloid leukemia, instead, they succumbed to a long-latency infiltrative mastocytosis that could be adoptively transferred to secondary recipients. Swapping of the C termini of ABL and ARG altered disease latency and phenotypes. In a detailed in vitro study, TEL/ARG strongly promoted mast cell differentiation in response to stem cell factor or interleukin-3, whereas TEL/ABL preferentially induced myeloid differentiation of hematopoietic stem/progenitor cells. These results indicate that ABL and ARG kinase activate distinct differentiation pathways to induce specific diseases in vivo, that is, myeloid leukemia and mastocytosis, respectively. Further elucidation of the differences in their properties should provide important insight into the pathogenic mechanisms of oncogenes of the ABL kinase family.

The development of laboratory tests for cancer in Japan with special reference to carcinoembryonic proteins

The present paper describes the present status of clinical tests for cancer in Japan. Since no cancer-specific substance has been found so far the clinical tests for cancer at present are always quantitative but not qualitative. Among these substances, alpha-fetoprotein is one of the most specific substances for cancer and its test is essential for diagnosis of hepatoma beins used worldwide. AFP is a specific product of liver cancer cells. The measurement of carcinoembryonic antigen in patient blood is a hopeful method for cancer diagnosis. This substance is not specifically produced by cancer cells, but the phenomenon of appearance in bloodstream appears to be cancer-specific. This may reflect the invasion of blood vessels in tissues such as colorectum, lung, etc., by infiltration of cancer cell. This is the reason for the appearance of CEA in a wide variety of cancers. There are many other clinical tests at present but these are only secondary aids for the diagnosis of cancer. This is the reason why the description concentrates mostly on AFP and CEA. The companies manufacturing the kits for these tests in Japan are also listed in this paper.

AV-65, a novel Wnt/β-catenin signal inhibitor, successfully suppresses progression of multiple myeloma in a mouse model

Multiple myeloma (MM) is a malignant neoplasm of plasma cells. Although new molecular targeting agents against MM have been developed based on the better understanding of the underlying pathogenesis, MM still remains an incurable disease. We previously demonstrated that β-catenin, a downstream effector in the Wnt pathway, is a potential target in MM using RNA interference in an in vivo experimental mouse model. In this study, we have screened a library of more than 100 000 small-molecule chemical compounds for novel Wnt/β-catenin signaling inhibitors using a high-throughput transcriptional screening technology. We identified AV-65, which diminished β-catenin protein levels and T-cell factor transcriptional activity. AV-65 then decreased c-myc, cyclin D1 and survivin expression, resulting in the inhibition of MM cell proliferation through the apoptotic pathway. AV-65 treatment prolonged the survival of MM-bearing mice. These findings indicate that this compound represents a novel and attractive therapeutic agent against MM. This study also illustrates the potential of high-throughput transcriptional screening to identify candidates for anticancer drug discovery.

Deletion of Ia-2 and/or Ia-2β in mice decreases insulin secretion by reducing the number of dense core vesicles

AIMS/HYPOTHESIS

Islet antigen 2 (IA-2) and IA-2β are dense core vesicle (DCV) transmembrane proteins and major autoantigens in type 1 diabetes. The present experiments were initiated to test the hypothesis that the knockout of the genes encoding these proteins impairs the secretion of insulin by reducing the number of DCV.

METHODS

Insulin secretion, content and DCV number were evaluated in islets from single knockout (Ia-2 [also known as Ptprn] KO, Ia-2β [also known as Ptprn2] KO) and double knockout (DKO) mice by a variety of techniques including electron and two-photon microscopy, membrane capacitance, Ca(2+) currents, DCV half-life, lysosome number and size and autophagy.

RESULTS

Islets from single and DKO mice all showed a significant decrease in insulin content, insulin secretion and the number and half-life of DCV (p < 0.05 to 0.001). Exocytosis as evaluated by two-photon microscopy, membrane capacitance and Ca(2+) currents supports these findings. Electron microscopy of islets from KO mice revealed a marked increase (p < 0.05 to 0.001) in the number and size of lysosomes and enzymatic studies showed an increase in cathepsin D activity (p < 0.01). LC3 protein, an indicator of autophagy, also was increased in islets of KO compared with wild-type mice (p < 0.05 to 0.01) suggesting that autophagy might be involved in the deletion of DCV.

CONCLUSIONS/INTERPRETATION

We conclude that the decrease in insulin content and secretion, resulting from the deletion of Ia-2 and/or Ia-2β, is due to a decrease in the number of DCV.

Oral health and cancer, cardiovascular, and respiratory mortality of Japanese

Cardiovascular diseases, cancer, and respiratory disease are major causes of death in developed countries. No study has simultaneously compared the contribution of oral health with these major causes of death. This study examined the association between oral health and cardiovascular diseases, cancer, and respiratory mortality among older Japanese. Self-administered questionnaires were mailed to participants in the Aichi Gerontological Evaluation Study (AGES) Project in 2003. Mortality data were analyzed for 4425 respondents. Three categories of oral health were used: 20 or more teeth, 19 or fewer teeth and eat everything, 19 or fewer teeth and eating difficulty. Sex, age, body mass index (BMI), self-rated health, present illness, exercise, smoking, alcohol, education, and income were used as covariates. During 4.28 years' follow-up, 410 people died, 159 from cancer, 108 of cardiovascular diseases, and 58 of respiratory disease. Multivariate adjusted Cox proportional hazard models showed that, compared with the respondents with 20 or more teeth, respondents with 19 or fewer teeth and with eating difficulty had a 1.83 and 1.85 times higher hazard ratio for cardiovascular disease mortality and respiratory disease mortality, respectively. There was no significant association with cancer mortality. Oral health predicted cardiovascular and respiratory disease mortality but not cancer mortality in older Japanese.

Geographical accessibility to dental care in the Japanese elderly

OBJECTIVE

The current research aims to clarify the factors relevant to elderly people's access to dental care in Japan, particularly focusing on geographical accessibility.

METHODS

The sample was taken from among the Japanese elderly, aged 65 and over, who responded to a postal survey conducted in 2003 (n = 2,192). Six types of geographical accessibility to the dental clinics were calculated using Geographic Information Systems. Logistic regression analysis was conducted using 'having a regular dentist' as a dependent variable and geographical accessibility as an explanatory variable.

RESULTS

The results showed an association between having a regular dentist and geographical accessibility only for females. In the univariate model, distance to the closest dental clinics (OR = 0.62 (95% CI: 0.43-0.90)), number of dental clinics at the school district level (OR = 1.14 (95% CI: 1.03-1.26)), number of dental clinics at the municipality level (OR = 1.02 (95% CI: 1.00-1.05)), and density distribution of dental clinics (OR = 1.56 (95% CI: 1.11-2.19)) showed significant relations with having a regular dentist. After controlling for demographic, socioeconomic, and health related variables, only the density distribution of dental clinics showed significant relations at the 5% level, although distance and number of dental clinics kept a marginal significance.

CONCLUSION

The current study verifies that geographical accessibility correlates with access to dental care among women, and that there were large gender differences concerning the issue of geographical access.