ABSTRACT
Synaptic phenotypes in living patients with psychiatric disorders are poorly characterized. Excitatory glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) is a fundamental component for neurotransmission. We recently developed a positron emission tomography (PET) tracer for AMPAR, [11C]K-2, the first technology to visualize and quantify AMPARs density in living human brain. In this study, we characterized patients with major psychiatric disorders with [11C]K-2. One hundred forty-nine patients with psychiatric disorders (schizophrenia, n = 42; bipolar disorder, n = 37; depression, n = 35; and autism spectrum disorder, n = 35) and 70 healthy participants underwent a PET scan with [11C]K-2 for measurement of AMPAR density. We detected brain regions that showed correlation between AMPAR density and symptomatology scores in each of four disorders. We also found brain areas with significant differences in AMPAR density between patients with each psychiatric disorder and healthy participants. Some of these areas were observed across diseases, indicating that these are commonly affected areas throughout psychiatric disorders. Schizophrenia, bipolar disorder, depression, and autism spectrum disorder are uniquely characterized by AMPAR distribution patterns. Our approach to psychiatric disorders using [11C]K-2 can elucidate the biological mechanisms across diseases and pave the way to develop novel diagnostics and therapeutics based on the synapse physiology.
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AIM: Although the antidepressant effect of ketamine on treatment-resistant depression (TRD) has been frequently reported in North American and European countries, evidence is scarce among the Asian population. We aimed to evaluate the efficacy and safety of intravenous ketamine in Japanese patients with TRD. METHODS: In this double-blind randomized placebo-controlled trial, 34 Japanese patients with TRD were randomized to receive either intravenous ketamine (0.5 mg/kg) or placebo, administered over 40 min, twice a week, for 2 weeks. The primary outcome was the change in the Montgomery Åsberg Depression Rating Scale (MADRS) total score from baseline to post-treatment. Secondary outcomes included changes in other depressive symptomatology scores and remission, response, and partial response rates. We also examined the association between baseline clinical demographic characteristics and changes in the MADRS total score. RESULTS: Intention-to-treat analysis indicated no significant difference in the decrease in MADRS total score between the groups (-8.1 ± 10.0 vs -2.5 ± 5.2, t[32] = 2.02, P = 0.052), whereas per-protocol analysis showed a significant reduction in the ketamine group compared to the placebo group (-9.1 ± 10.2 vs -2.7 ± 5.3, t[29] = 2.22, P = 0.034). No significant group differences were observed in other outcomes. Adverse events were more frequent in the ketamine group than in the placebo group, and no serious adverse events were reported. A higher baseline MADRS total score and body mass index were associated with a greater reduction in the MADRS total score. CONCLUSION: Intravenous ketamine outperformed placebo in Japanese patients with TRD who completed the study, suggesting that ketamine could alleviate depressive symptoms of TRD across diverse ethnic populations.
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The administration of anti-vascular endothelial growth factor drugs in the posterior eye segment with sustained release through less invasive methods is a challenge in the treatment of age-related macular disease. We developed a flexible capsule device using porous poly(dimethylsiloxane) (PDMS) that was able to release ranibizumab. The porous PDMS sheet was fabricated by salt-leaching of a micro-sectioned PDMS sheet containing salt microparticles. Observation with scanning electron microscopy revealed that the pore densities could be adjusted by the concentration of salt. The in vitro release study showed that the release rate of fluorescein isothiocyanate-tagged albumin could be adjusted based on the pore density of the porous PDMS sheet. Ranibizumab could be released in a sustained-release manner for 16 weeks. The device was implanted on the sclera; its efficacy in terms of the suppression of laser-induced choroidal neovascularization (CNV) in rats was compared with that of monthly intravitreal injections of ranibizumab. At 8 and 18 weeks after implantation, the CNV area was significantly reduced in rats that received the ranibizumab-releasing device compared with those that received the placebo device. However, although monthly intravitreal injections of ranibizumab reduced CNV for 8 weeks, this reduction was not sustained for 18 weeks. In conclusion, we demonstrated a novel controlled-release device using a porous PDMS sheet that could suppress CNV via a less invasive transscleral route versus intravitreal injections. This device may also reduce the occurrence of side effects associated with frequent intravitreal injections.
Subject(s)
Choroidal Neovascularization , Ranibizumab , Rats , Animals , Ranibizumab/therapeutic use , Porosity , Choroidal Neovascularization/drug therapy , Lasers , Angiogenesis Inhibitors/therapeutic useABSTRACT
In this study, we developed a subcutaneous insulin-releasing device consisting of a disk-shaped capsule and drug formulation comprised of poly(ethylene glycol) dimethacrylates, then evaluated its efficacy on retinal function in streptozotocin (STZ)-induced diabetic rats. In vitro release studies showed that recombinant human insulin was released with a constant rate for more than 30 days. The device was able to maintain a basal level of blood glucose in diabetic rats for a prolonged period of more than 30 days, simultaneously preventing a decrease in body weight. For assessing the pharmacological effect of the device on retinal function in diabetic rats, electroretinograms were conducted for 12 weeks. The reduction in amplitude and delay in implicit time were attenuated by the device during the initial 4 weeks of application. The increase in gene expression of protein kinase C (PKC)-γ and caspase-3 in the diabetic retina was also attenuated by the device. Immunohistochemistry showed that the increase in glial fibrillary acidic protein expression in the diabetic retina was attenuated by the device. Histological evaluation of subcutaneous tissue around the device showed the biocompatibility of the device. In conclusion, the insulin-releasing device attenuated the reduction of retinal function in STZ-induced diabetic conditions for 4 weeks and the efficacy of the device might be partially related to PKC signaling in the retina. The long-term ability to control the blood glucose level might help to reduce the daily frequency of insulin injections.
Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetic Retinopathy/prevention & control , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Insulin/administration & dosage , Animals , Blood Glucose , Drug Liberation , Electroretinography , Gene Expression Regulation/drug effects , Hybrid Renal Replacement Therapy , Insulin/pharmacology , Male , Rats , Rats, Sprague-Dawley , Retina/drug effects , Retina/metabolismABSTRACT
Minimally invasive delivery of a sustained drug release device to the body is a promising approach for treating chronic conditions such as retinal diseases. Herein, we describe a sheet-type device capable of sustained drug release and deployment control after being applied to the body through a small opened hole via a syringe-type injector. Such device consists of a four-layered structure of thin photopolymerized sheets, which are in turn made of different ratios of a mixture of polyethylene glycol dimethacrylate (PEGDM) and triethylene glycol dimethacrylate (TEGDM). A layer containing a model drug, i.e., fluorescein, was sandwiched between a controlled release and guard layer to achieve sustained unidirectional drug release. A deployment layer was then attached onto the guard layer to control the curvature of the device following deployment. The sheet-type device was sufficiently flexible to be rolled up and could be inserted into a syringe-type injector. When the device was injected into the subconjunctival space of a rabbit eye through a small opened hole, it unfolded to fit the eyeball curvature. Moreover, homogenates of the choroid/retinal pigment epithelium (RPE) as well as the retina exhibited fluorescence during 4 weeks after implantation, confirming that the drug could be delivered to the retina by using the device. This developed sheet-type device offers the possibility of achieving minimally invasive transplantation into diseased tissues and organs, and could provide improved therapeutic modalities as well as reduce possible side effects.
Subject(s)
Delayed-Action Preparations , Drug Delivery Systems/instrumentation , Animals , Eye/metabolism , Fluorescein/metabolism , Male , RabbitsABSTRACT
Introduction Data on the knowledge about antipsychotic medications prescribed in patients with schizophrenia are very limited. Moreover, it remains unclear how patients' knowledge about prescribed antipsychotics affects medication adherence. Methods ighty-one Japanese outpatients with schizophrenia according to the International Classification of Diseases, 10th edition, were included. Patients' knowledge of the primary antipsychotics prescribed to them in terms of therapeutic effects, type, and implicated neurotransmitters was assessed with a multiple-choice questionnaire developed for this study. Medication possession ratios (MPRs) were compared between patients who answered correctly and those who did not in each category. Results The percentages of subjects who answered correctly regarding antipsychotic effects, type, and implicated neurotransmitters were low at 30.9%, 30.9%, and 7.4%, respectively. No differences were found in MPRs between subjects who answered correctly and those who did not. Discussion Our preliminary results indicate that patients lack knowledge about their antipsychotic medications. More concerning, they suggest that knowledge about prescribed antipsychotics may not directly translate into actual medication adherence in patients with schizophrenia.
Subject(s)
Antipsychotic Agents/therapeutic use , Knowledge , Medication Adherence , Schizophrenia/drug therapy , Schizophrenic Psychology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Cross-Sectional Studies , Drug Prescriptions/statistics & numerical data , Female , Humans , Japan , Linear Models , Male , Middle Aged , Retrospective Studies , Surveys and Questionnaires , Young AdultABSTRACT
Transscleral drug delivery is becoming increasingly popular to manage posterior eye diseases. To evaluate the clinical application of a transscleral, sustained, unoprostone (UNO)-release device (URD) constructed of photopolymerized tri(ethyleneglycol) dimethacrylate and poly(ethyleneglycol) dimethacrylate, we evaluated physicochemical and biological properties of this device. The URD consists of a drug-impermeable reservoir and a semi-permeable cover. The in vitro release rate of UNO from the URD increased with increasing temperatures from 20 to 45 °C. Scanning electron microscopy and atomic-force microscopy showed that the border between the reservoir and drug formulation was sharply defined but that between the cover and drug was poorly determined, indicating that UNO could permeate only through the cover. For stability tests, the URDs were sterilized with ethylene oxide gas and stored at 40 °C/75% for 3 and 6 months and at 25 °C/60% for 3, 6, 9, 12, 18, and 24 months; UNO content and release rate at 37 °C were then evaluated. There was no significant decrease in either UNO content or release rate after the storage conditions. Cytotoxicity was evaluated by examining the colony formation of Chinese hamster fibroblast V79 cells in a media extract of the URD without UNO. This extract did not affect colony formation of V79 cells, indicating the cytocompatibility of the URD. In conclusion, the URD was physically stable for 24 months and is potentially useful for clinical application.
Subject(s)
Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/chemistry , Dinoprost/analogs & derivatives , Methacrylates/chemistry , Polyethylene Glycols/chemistry , Absorption, Physicochemical , Antihypertensive Agents/administration & dosage , Antihypertensive Agents/chemistry , Delayed-Action Preparations/toxicity , Diffusion , Dinoprost/administration & dosage , Dinoprost/chemistry , Dinoprost/therapeutic use , Drug Compounding/methodsABSTRACT
We evaluated the effects of a transscleral drug delivery device, consisting of a reservoir and controlled-release cover, which were made of photopolymerized polyethylene glycol dimethacrylate and triethylene glycol dimethacrylate, combined at different ratios. Geranylgeranylacetone (GGA), a heat-shock protein (HSP) inducer, was loaded into the device. The GGA was released from the device under zero-order kinetics. At both 1 week and 4 weeks after device implantation on rat sclera, HSP70 gene and protein expression were up-regulated in the sclera-choroid-retinal pigment epithelium fraction of rat eyes treated with the GGA-loaded device compared with rat eyes treated with saline-loaded devices or eyes of non-treated rats. Flash electroretinograms were recorded 4 days after white light exposure (8000 lx for 18 h). Electroretinographic amplitudes of the a- and b-waves were preserved significantly in rats treated with GGA-loaded devices compared with rats treated with saline-loaded devices. Histological examination showed that the outer nuclear layer thickness was preserved in rats that had the GGA-loaded device. These results may show that transscleral GGA delivery using our device may offer an alternative method to treat retinal diseases.
Subject(s)
Diterpenes/administration & dosage , Drug Delivery Systems/methods , Retinal Diseases/prevention & control , Sclera/metabolism , Animals , Blotting, Western , Choroid/drug effects , Choroid/metabolism , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/pharmacokinetics , Diterpenes/pharmacokinetics , Drug Delivery Systems/instrumentation , Electroretinography , Gene Expression/drug effects , HSP70 Heat-Shock Proteins/genetics , HSP70 Heat-Shock Proteins/metabolism , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Light/adverse effects , Male , Methacrylates/chemistry , Polyethylene Glycols/chemistry , Polymers/chemistry , Polymethacrylic Acids/chemistry , Rats, Sprague-Dawley , Retina/drug effects , Retina/metabolism , Retina/radiation effects , Retinal Diseases/etiology , Retinal Diseases/physiopathology , Retinal Pigment Epithelium/drug effects , Retinal Pigment Epithelium/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Thioredoxins/genetics , Thioredoxins/metabolismABSTRACT
Age-related macular degeneration is the leading cause of legal blindness among older individuals. Therefore, the development of new therapeutic agents and optimum drug delivery systems for its treatment are crucial. In this study, we investigate whether clotrimazole (CLT) is capable of protecting retinal cells against oxidative-induced injury and the possible inhibitory effect of a sustained CLT-release device against light-induced retinal damage in rats. In vitro results indicated pretreatment of immortalized retinal pigment epithelium cells (RPE-J cells) with 10-50 µM CLT before exposure to oxygen/glucose deprivation conditions for 48 h decreased the extent of cell death, attenuated the percentage of reactive oxygen species-positive cells, and decreased the levels of cleaved caspase-3. The device consists of a separately fabricated reservoir, a CLT formulation, and a controlled release cover, which are made of poly(ethyleneglycol) dimethacrylate (PEGDM) and tri(ethyleneglycol) dimethacrylate (TEGDM). The release rate of CLT was successfully tuned by changing the ratio of PEGDM/TEGDM in the cover. In vivo results showed that use of a CLT-loaded device lessened the reduction of electroretinographic amplitudes after light exposure. These findings indicate that the application of a polymeric CLT-loaded device may be a promising method for the treatment of some retinal disorders.
Subject(s)
Clotrimazole/administration & dosage , Drug Implants , Macular Degeneration/drug therapy , Animals , Cell Line, Transformed , Clotrimazole/pharmacology , Clotrimazole/therapeutic use , Delayed-Action Preparations , Electroretinography , Male , Oxidation-Reduction , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Retinal Pigment Epithelium/cytology , Retinal Pigment Epithelium/drug effects , Retinal Pigment Epithelium/metabolismABSTRACT
We constructed brain-derived neurotrophic factor (BDNF) expressing rat retinal pigment epithelial (RPE) cells by stable transfection of BDNF cDNA, and the RPE cells were cultured on a cross-linked collagen sheet (Coll-RPE-BDNF). BDNF expression of the Coll-RPE-BDNF was confirmed by western blot, and the Coll-RPE-BDNF was transplanted into the rabbit sclera. In vivo BDNF expression was confirmed by His expression that was linked to the expressing BDNF. The effect of the released BDNF was examined in a rabbit acute high intraocular pressure system by electroretinogram and histological examination. Statistically significant preservation of ERG b wave amplitude was observed in the rabbits treated by Coll-RPE-BDNF when compared to that of no treatment. Statistically significant preservation of the thickness of the inner nuclear layer at the transplanted area was observed in the rabbits treated by Coll-RPE-BDNF compared to that of no treatment. Intra-scleral Coll-RPE-BDNF transplantation may partially rescue retinal cells from acute high intraocular pressure.
Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Cell Transplantation/methods , Intraocular Pressure/physiology , Retina/physiology , Retinal Diseases/surgery , Retinal Pigment Epithelium/transplantation , Animals , Collagen/pharmacology , Cross-Linking Reagents/pharmacology , Electroretinography , Graft Survival , Male , Rabbits , Rats , Retina/cytology , Retinal Diseases/etiology , Retinal Pigment Epithelium/cytology , Retinal Pigment Epithelium/metabolism , Sclera/surgeryABSTRACT
BACKGROUND: The dominant diagnostic model of the classification of depression today is unitarian; however, since Kurt Schneider (1920) introduced the concept of endogenous depression and reactive depression, the binary model has still often been used on a clinical basis. Notwithstanding this, to our knowledge, there have been no collective data on how psychiatrists differentiate these two conditions. We therefore conducted a survey to examine how psychiatrists in Japan differentiate patients with major depressive disorder who present mainly with melancholic features and those with reactive features. METHODS: Three case scenarios of melancholic and reactive depression, and one-in-between were prepared. These cases were designed to present with at least 5 symptoms listed in the DSM-IV-TR with severity being mild. We have sent the questionnaires regarding treatment options and diagnosis for those three cases on a 7-point Likert scale (1 = "not appropriate", 4 = "cannot tell", and 7 = "appropriate"). Five hundred and two psychiatrists from over one hundred hospitals and community clinics throughout Japan have participated in this survey. RESULTS: The melancholic case resulted significantly higher than the reactive case on either antidepressants (mean ± SD: 5.9 ± 1.2 vs. 3.6 ± 1.7, p < 0.001), hypnotics (mean ± SD: 5.5 ± 1.1 vs. 5.0 ± 1.3, p < 0.001), and electroconvulsive therapy (mean ± SD: 1.5 ± 0.9 vs. 1.2 ± 0.6, p < 0.001). On the other hand, the reactive case resulted in significantly higher scores compared to the melancholic case and the one- in-between cases in regards to psychotherapy (mean ± SD: 4.9 ± 1.4 vs. 4.3 ± 1.4 vs. 4.7 ± 1.5, p < 0.001, respectively). Scores for informing patients that they suffered from "depression" were significantly higher in the melancholic case, compared to the reactive case (mean ± SD: 4.7 ± 1.7 vs. 2.2 ± 1.4, p < 0.001). CONCLUSIONS: Japanese psychiatrists distinguish between major depressive disorder with melancholic and reactive features, and thus choose different treatment strategies regarding pharmacological treatment and psychotherapy.
Subject(s)
Attitude of Health Personnel , Depressive Disorder, Major/diagnosis , Depressive Disorder, Major/therapy , Practice Patterns, Physicians'/statistics & numerical data , Severity of Illness Index , Adjustment Disorders , Adult , Antidepressive Agents/therapeutic use , Depressive Disorder/diagnosis , Depressive Disorder, Major/classification , Diagnostic and Statistical Manual of Mental Disorders , Electroconvulsive Therapy/methods , Female , Humans , Hypnotics and Sedatives/therapeutic use , Japan , Male , Middle Aged , Surveys and QuestionnairesABSTRACT
BACKGROUND: We have developed crosslinked salmon-derived atelocollagen sponge, which has a denaturation temperature of 47 degrees Celsius. The purpose of this study is to evaluate the fundamental in vivo efficacy of the osteogenic protein (OP) -1 containing salmon-derived collagen sponge disc (SCS) on cartilage regeneration, using a rabbit model. METHODS: A total of 24 rabbits were used in this study. In each animal, a full-thickness osteochondral defect was created in each femoral trochlea. Then, each 12 rabbits were randomly divided into the two groups. In Group I, an OP1-SCS disc was implanted into the defect in the right knee. In Group II, a SCS disc without OP-1 was implanted into the defect in the right knee. A control group of 12 rabbits was assembled from randomly-selected left knees from among the first two groups. In Group-III, we applied no treatment for a defect in the left knee to obtain the untreated control. All rabbits were sacrificed at 12 weeks after surgery. In each group, 10 animals were used for histological and immunohistological evaluations, and the remaining 2 were used for real-time polymerase chain reaction (PCR) analyses. RESULTS: In Group I, a regenerated cartilage tissue rich in proteoglycan and type-2 collagen was found at 12 weeks, although the width was thicker than that of Group II. In Group II, the defect was filled with thick inhomogeneous tissues, including cartilage, fibrous, and bone tissues at 12 weeks. Concerning the gross observation and histological scores at 12 weeks, the ANOVA showed significant differences (p < 0.0001, and p < 0.0001, respectively). The post-hoc test indicated that the gross observation and histological scores of Group I was significantly greater than those of Groups II (p = 0.035, and p = 0.0104, respectively) and III (p < 0.0001, and p < 0.0001, respectively), while Group II was significantly greater than Group III (p = 0.0069, and p = 0.005, respectively). The real time PCR analysis showed that gene expression of type-2 collagen and aggrecan of Group I was greater than that of Group II. CONCLUSIONS: The present study clearly demonstrated that the implantation of the OP1-SCS disc without any cultured cells may induce spontaneous hyaline-like cartilage regeneration to greater degrees than implantation of only the salmon-derived collagen sponge disc.
Subject(s)
Bone Morphogenetic Protein 7/administration & dosage , Cartilage, Articular/drug effects , Cartilage, Articular/physiology , Collagen/administration & dosage , Drug Carriers/administration & dosage , Regeneration/drug effects , Animals , Bone Morphogenetic Protein 7/chemical synthesis , Collagen/chemical synthesis , Drug Carriers/chemical synthesis , Female , Rabbits , Random Allocation , Regeneration/physiology , SalmonABSTRACT
Olanzapine is one of the SGAs (second-generation antipsychotics) which have been used for the treatment of patients with schizophrenia and bipolar disorder in Japan. Olanzapine has various affinities for multiple receptors, including dopamine D2 receptor, serotonin 5-HT2A, 5-HT2C, 5-HT6 receptors, and adrenaline alpha1, histamine H1, muscarine M1-M5 receptors as well. Therefore, olanzapine is known as MARTA(multi-acting receptor targeted antipsychotics). Numerous studies have been conducted to compare the effectiveness of olanzapine between SGAs and FGAs (first-generation antipsychotics). According to the head-to-head meta-analysis and large-scale studies like CATIE and EUFEST, olanzapine seems to have not only higher efficacy but also less discontinuation comparing to other anti-psychotics.
Subject(s)
Antipsychotic Agents/therapeutic use , Benzodiazepines/therapeutic use , Bipolar Disorder/drug therapy , Schizophrenia/drug therapy , Adolescent , Antipsychotic Agents/adverse effects , Antipsychotic Agents/chemistry , Benzodiazepines/adverse effects , Benzodiazepines/chemistry , Bipolar Disorder/diagnosis , Clozapine/chemistry , Humans , Male , Olanzapine , Treatment OutcomeABSTRACT
The objectives of this study were to develop a sustained-release device for carteolol hydrochloride (CH) and investigate any potential difference in the intraocular distribution of this agent between the transscleral administration of the device and treatment with eyedrops. The device was formulated with photocurable resin, poly (ethyleneglycol) dimethacrylate, to fit within the curve of the rabbit eyeball. In vitro study showed that CH was released in a sustained-release manner for 2 weeks. The concentration of CH in the retina, choroid/retinal pigment epithelium, sclera, iris, and aqueous humor was determined by high-performance liquid chromatography. Transscleral administration was able to deliver CH to the posterior segment (i.e., retina and choroid/retinal pigment epithelium) rather than the anterior segment (i.e., aqueous humor), while eyedrops delivered CH only to the anterior segment. Transscleral administration could deliver CH to aqueous humor at half the concentration versus treatment with eyedrops and reduced intraocular pressure (IOP) at 1 day after implantation; however, the IOP-lowering effect was not sustained thereafter. In conclusion, transscleral drug delivery may be a useful method for the reduction of IOP. Notably, the aqueous concentration must be equal to that delivered by the eyedrops, and this approach might be preferable for drug delivery to the posterior segment of the eye.
ABSTRACT
Retinal cells are irreparably damaged by diseases such as age-related macular degeneration (AMD). A promising method to restore partial or whole vision is through cell-based transplantation to the damaged location. However, cell transplantation using conventional vitreous surgery is an invasive procedure that may induce infections and has a high failure rate of cell engraftment. In this study, we describe the fabrication of a biodegradable composite nanosheet used as a substrate to support retinal pigment epithelial (RPE-J) cells, which can be grafted to the sub-retinal space using a minimally invasive approach. The nanosheet was fabricated using polycaprolactone (PCL) and collagen in 80:20 weight ratio, and had size of 200 µm in diameter and 300 nm in thickness. These PCL/collagen nanosheets showed excellent biocompatibility and mechanical strength in vitro. Using a custom designed 27-gauge glass needle, we successfully transplanted an RPE-J cell loaded nanosheet into the sub-retinal space of a rat model with damaged photoreceptors. The cell loaded nanosheet did not trigger immunological reaction within 2 weeks of implantation and restored the retinal environment. Thus, this composite PCL/collagen nanosheet holds great promise for organized cell transplantation, and the treatment of retinal diseases.
Subject(s)
Macular Degeneration , Retinal Pigment Epithelium , Rats , Animals , Retina , Collagen , Macular Degeneration/surgery , Cell TransplantationABSTRACT
The excitatory glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) contribute to epileptogenesis. Thirty patients with epilepsy and 31 healthy controls are scanned using positron emission tomography with our recently developed radiotracer for AMPARs, [11C]K-2, which measures the density of cell-surface AMPARs. In patients with focal-onset seizures, an increase in AMPAR trafficking augments the amplitude of abnormal gamma activity detected by electroencephalography. In contrast, patients with generalized-onset seizures exhibit a decrease in AMPARs coupled with increased amplitude of abnormal gamma activity. Patients with epilepsy had reduced AMPAR levels compared with healthy controls, and AMPARs are reduced in larger areas of the cortex in patients with generalized-onset seizures compared with those with focal-onset seizures. Thus, epileptic brain function can be regulated by the enhanced trafficking of AMPAR due to Hebbian plasticity with increased simultaneous neuronal firing and compensational downregulation of cell-surface AMPARs by the synaptic scaling.
Subject(s)
Epilepsy , Receptors, AMPA , Humans , Receptors, AMPA/physiology , Neurons , SeizuresABSTRACT
PURPOSE: To determine whether intravitreal vasohibin-1 will reduce the grade of the choroidal neovascularization in monkey eyes. METHODS: Choroidal neovascularizations were induced in 12 monkey eyes by laser photocoagulation. Three monkeys were evaluated for the safety of the vasohibin-1 injections, 6 monkeys for the effects of a single injection, and 3 monkeys for repeated injections of vasohibin-1. Ophthalmoscopy, fluorescein angiography, focal electroretinograms, and optical coherence tomography were used for the evaluations. The level of vascular endothelial growth factor in the aqueous was determined by enzyme-linked immunosorbent assay. Immunohistochemistry was performed. RESULTS: An intravitreal injection of 10 µg of vasohibin-1 induced mild intraocular inflammation. Eyes with an intravitreal injection of 0.1 µg and 1.0 µg of vasohibin-1 had significant less fluorescein leakage from the choroidal neovascularizations and larger amplitude focal electroretinograms than that of vehicle-injected eyes. Similar results were obtained by repeated injections of 0.1 µg of vasohibin-1. Immunohistochemistry showed that vasohibin-1 was expressed mainly in the endothelial cells within the choroidal neovascularizations. The vascular endothelial growth factor level was not significantly altered by intravitreal vasohibin-1. CONCLUSION: The reduction of the laser-induced choroidal neovascularizations and preservation of macular function in monkey by intravitreal vasohibin-1 suggest that it should be considered for suppressing choroidal neovascularizations in humans.
Subject(s)
Angiogenesis Inhibitors/administration & dosage , Cell Cycle Proteins/administration & dosage , Choroidal Neovascularization/drug therapy , Angiogenesis Inhibitors/metabolism , Animals , Cell Cycle Proteins/metabolism , Choroidal Neovascularization/metabolism , Choroidal Neovascularization/pathology , Choroidal Neovascularization/physiopathology , Disease Models, Animal , Electroretinography/drug effects , Enzyme-Linked Immunosorbent Assay , Fluorescein Angiography , Immunohistochemistry , Intravitreal Injections , Macaca , Ophthalmoscopy , Tomography, Optical Coherence , Vascular Endothelial Growth Factor A/metabolismABSTRACT
Background: To become a doctor with a high level of professionalism and ethical standards, it is important to have and maintain a high level of motivation right from medical school. However, studies in Japan have not quantitatively investigated the factors related to motivation immediately after enrollment. This study aimed to identify the demographic factors that influence the motivation of medical students immediately after admission. Methods: A cross-sectional single-center study was conducted. First-year medical students answered our questionnaire three weeks after the admission. The questionnaire comprised 16 demographic items and the 28-item Academic Motivation Scale, which was used to quantify motivation. Results: Our analysis showed that amotivation, representing low levels of self-determinant motivation, was significantly higher in students whose parents were medical professionals and in students who did not talk about their problems than in those whose parents were not medical professionals and those who did talk about their problems. Intrinsic motivation, which indicates the level of self-determinant motivation, was significantly lower in students who belonged to a sports club. Conclusions: We suggest that having parents who are medical professionals may be associated with an individual's decreased motivation when entering medical school in Japan. Though this is a novel finding, further research is needed to analyze this relationship.
ABSTRACT
Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A serological test is used to assess the efficacy of vaccination. It has been reported that anti-SARS-CoV-2 spike (S) and neutralizing antibody (Ab) levels are lower following vaccination in patients with rheumatic disease. Here, we investigated anti-SARS-CoV-2 S and neutralizing Abs in vaccinated rheumatoid arthritis (RA) patients in Japan. Anti-SARS-CoV-2 S and neutralizing Abs were quantified in 101 RA patients and 117 controls. Anti-SARS-CoV-2 S Ab levels were lower in RA patients than both earlier after vaccination in controls (mean RA 324.1 ± 591.8 SDM vs. control 1216.6 ± 854.4 [U/mL], p < 0.0001) and later after vaccination (324.1 ± 591.8 vs. 582.0 ± 415.6 [U/mL], p = 0.0002). The interval between vaccination of the RA patients and serum collection was longer than for controls early after vaccination (142.1 ± 31.6 vs. 98.3 ± 11.2 [days], p < 0.0001), but shorter than the later sample from the controls (142.1 ± 31.6 vs. 257.3 ± 11.2 [days], p < 0.0001). Importantly, anti-SARS-CoV-2 neutralizing Ab titers in RA patients were higher than in either early or later control samples (10.7 ± 4.9 vs. 8.6 ± 6.6 [%], p = 0.0072, and 10.7 ± 4.9 vs. 3.1 ± 3.7 [%], p < 0.0001, respectively). Anti-SARS-CoV-2 S Ab titers in vaccinated RA patients were lower than in controls, but they were influenced by other clinical manifestations. Anti-SARS-CoV-2 neutralizing Ab levels were independently increased in RA.