Molecular detection and characterization of Acanthamoeba infection in dogs and its association with keratitis in Korea.

Acanthamoeba infection is associated with keratitis in humans; however, its association with keratitis in dogs remains unclear. To investigate this possibility, we collected 171 conjunctival swab samples from dogs with eye-related diseases (65 with keratitis and 106 without keratitis) at Chungbuk National University Veterinary Teaching Hospital, Korea, from August 2021 to September 2022. Polymerase chain reaction identified 9 samples (5.3%) as Acanthamoeba positive; of these, 3 were from dogs with keratitis (4.6%) and 6 were from dogs without keratitis (5.7%). Our results indicated no significant association between Acanthamoeba infection and keratitis, season, sex, or age. All Acanthamoeba organisms found in this study had the genotype T4, according to 18S ribosomal RNA analysis. Acanthamoeba infection in dogs might have only a limited association with keratitis.

Beneficial Effect of Sirolimus-Pretreated Mesenchymal Stem Cell Implantation on Diabetic Retinopathy in Rats.

BACKGROUND: Diabetic retinopathy (DR) is a vision-threatening complication that affects virtually all diabetic patients. Various treatments have been attempted, but they have many side effects and limitations. Alternatively, stem cell therapy is being actively researched, but it faces challenges due to a low cell survival rate. In this study, stem cells were pretreated with sirolimus, which is known to promote cell differentiation and enhance the survival rate. Additionally, the subconjunctival route was employed to reduce complications following intravitreal injections. METHODS: Diabetes mellitus was induced by intraperitoneal injection of 55 mg/kg of streptozotocin (STZ), and DR was confirmed at 10 weeks after DM induction through electroretinogram (ERG). The rats were divided into four groups: intact control group (INT), diabetic retinopathy group (DR), DR group with subconjunctival MSC injection (DR-MSC), and DR group with subconjunctival sirolimus-pretreated MSC injection (DR-MSC-S). The effects of transplantation were evaluated using ERG and histological examinations. RESULTS: The ERG results showed that the DR-MSC-S group did not significantly differ from the INT in b-wave amplitude and exhibited significantly higher values than the DR-MSC and DR groups (p < 0.01). The flicker amplitude results showed that the DR-MSC and DR-MSC-S groups had significantly higher values than the DR group (p < 0.01). Histological examination revealed that the retinal layers were thinner in the DR-induced groups compared to the INT group, with the DR-MSC-S group showing the thickest retinal layers among them. CONCLUSIONS: Subconjunctival injection of sirolimus-pretreated MSCs can enhance retinal function and mitigate histological changes in the STZ-induced DR rat model.

Successful surgical attenuation of portosystemic shunt in a dog with imaging-diagnosed portal vein aplasia.

An 8-month-old female Maltese dog was referred for examination with a history of circling, dullness, and drooling. Serum biochemical analysis revealed hyperammonemia, with microhepatica observed on radiography. Computed tomography angiography revealed a portosystemic shunt originating from the right gastric vein and inserting into the prehepatic caudal vena cava. Portal blood flow to the liver was not observed. Based on computed tomography angiography, the dog was tentatively diagnosed with portosystemic shunt with portal vein aplasia. An exploratory laparotomy was done to obtain a definitive diagnosis. The dog had no subjective clinical signs of portal hypertension during a temporary occlusion test of the portosystemic shunt. A thin-film band was placed around the portosystemic shunt to achieve partial attenuation. There was no evidence of hepatic encephalopathy in the long term after surgery, and the dog's liver volume increased over time. Computed tomography angiography at 6 mo after surgery identified well-visualized intrahepatic portal branches. Key clinical message: We inferred that a direct occlusion test is a reliable diagnostic technique that overcomes the limitations of diagnostic imaging methods, including computed tomography angiography, and is a good technique for determining whether surgical attenuation is possible in dogs with suspected portal vein aplasia.

Atténuation chirurgicale réussie d'un shunt porto-systémique chez un chien avec une aplasie de la veine porte diagnostiquée par imagerie. Une femelle bichon maltais âgée de 8 mois a été référée pour examen avec une histoire de tournis, apathie et salivation excessive. L'analyse biochimique du sérum a révélé une hyperammionémie, avec un petit foie observé lors des radiographies. Une angiographie par tomodensitométrie a révélé un shunt porto-systémique prenant son origine de la veine gastrique droite et s'insérant dans la veine cave caudale pré-hépatique. Le flot sanguin porte au foie n'était pas observé. Sur la base de l'angiographie par tomodensitométrie, un diagnostic présumé de shunt porto-systémique avec aplasie de la veine porte a été émis. Une laparotomie exploratoire a été effectuée afin d'obtenir un diagnostic définitif. Le chien ne présentait pas de signe clinique subjectif d'hypertension portale durant un test d'occlusion temporaire du shunt porto-systémique. Une bande de film mince a été placée autour du shunt porto-systémique pour causer une réduction partielle. Il n'y avait aucune évidence d'encéphalopathie hépatique à long terme après la chirurgie, et le volume du foie du chien a augmenté dans le temps. Une angiographie par tomodensitométrie effectuée 6 mo après la chirurgie a permis de bien visualiser des branches portes intra-hépatiques.Message clinique clé :Nous avons déduit qu'un test d'occlusion est une technique diagnostique fiable qui surpasse les limites des méthodes d'imagerie diagnostique, incluant l'angiographie par tomodensitométrie, et est une bonne technique pour déterminer si une réduction chirurgicale est possible chez des chiens chez qui on soupçonne une aplasie de la veine porte.(Traduit par Dr Serge Messier).

Evaluation of ciliary cleft changes after phacoemulsification using ultrasound biomicroscopy in dogs with cataracts.

Introduction: Glaucoma is one of the most serious complications that causes irreversible blindness after phacoemulsification in dogs; however, a clear mechanism has not been elucidated. This study aimed to analyse the possible anatomical factors associated with glaucoma after phacoemulsification using parameters that reflect the anatomical characteristics of dogs. Materials and methods: A total of 69 eyes of 48 dogs were included in this study. The patients were divided into three groups: normal eye (n = 18), cataract (n = 39), and post-phacoemulsification for at least 2 months after surgery (post-phaco, n = 12). For further analysis, the dogs were subdivided into two groups according to cataract stage: phacoemulsification non-candidate and candidate groups. Non-cataracts and incipient cataracts were categorized into the non-candidate group, whereas immature and mature cataracts were categorized into the candidate group. Measurements of the ciliary cleft parameters, including the area of the ciliary cleft (CCA), length of the ciliary cleft (CCL), width of the ciliary cleft (CCW), iridocorneal angle, and angle opening distance, were obtained using ultrasound biomicroscopy. Results: CCA, CCL, and CCW were significantly higher in the candidate group than in the non-candidate group. CCA, CCL, and CCW were significantly reduced in the post-phaco group compared to those in the cataract group. Based on these results, we found that the ciliary cleft expanded in cataract-affected eyes and narrowed after phacoemulsification. This may indicate that the space between the trabecular meshworks became narrower, potentially leading to an increase in the resistance of the aqueous humor. Conclusion: A narrowed ciliary cleft after phacoemulsification may be an anatomical factor associated with glaucoma.

Tacrolimus Improves Therapeutic Efficacy of Umbilical Cord Blood-Derived Mesenchymal Stem Cells in Diabetic Retinopathy by Suppressing DRP1-Mediated Mitochondrial Fission.

Diabetic retinopathy (DR) is a leading cause of blindness in diabetic patients. Umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) are emerging as a promising new drug for degenerative disease associated with diabetes. Recent studies have shown that high glucose-increased excessive calcium levels are a major risk factor for mitochondrial reactive oxygen species (mtROS) accumulation and apoptosis. This study aimed to investigate the role of high glucose-induced NFATC1 signaling in mitochondrial oxidative stress-stimulated apoptosis and the effect of tacrolimus on the therapeutic efficacy of subconjunctival transplantation of UCB-MSCs in a DR rat model. High glucose increased mtROS and cleaved caspase-9 expression in UCB-MSCs. High glucose conditions increased O-GlcNAcylated protein expression and nuclear translocation of NFATC1. Tacrolimus pretreatment recovered high glucose-induced mtROS levels and apoptosis. In the DR rat model, subconjunctival transplantation of tacrolimus-pretreated MSCs improved retinal vessel formation, retinal function, and uveitis. In high glucose conditions, tacrolimus pretreatment reduced protein and mRNA expression levels of DRP1 and inhibited mitochondrial fission. In conclusion, we demonstrated that high glucose-induced O-GlcNAcylation activates NFATC1 signaling, which is important for DRP1-mediated mitochondrial fission and mitochondrial apoptosis. Finally, we proposed NFATC1 suppression by tacrolimus as a promising therapeutic strategy to improve the therapeutic efficacy of UCB-MSC transplantation for DR treatment.

Preventive Effects of Exosome-Rich Conditioned Medium From Amniotic Membrane-Derived Mesenchymal Stem Cells for Diabetic Retinopathy in Rats.

Purpose: Diabetic retinopathy (DR) is an important disease that causes vision loss in many diabetic patients. Stem cell therapy has been attempted for treatment of this disease; however, it has some limitations. This study aimed to evaluate the preventive efficacy of exosome-rich conditioned medium (ERCM) derived from amniotic membrane stem cells for DR in rats. Methods: Twenty-eight 8-week-old male Sprague-Dawley rats were divided into three groups: group 1, normal control (Con) group; group 2, diabetes mellitus (DM) group; and group 3, DM with ERCM-treated (DM-ERCM) group. DM was induced by intraperitoneal injection of streptozotocin. The DM-ERCM group received ERCM containing 1.2 × 109 exosomes into subconjunctival a total of four times every 2 weeks. Results: On electroretinogram, the DM-ERCM group had significantly higher b-wave and flicker amplitudes than those in the DM group. In fundoscopy, retinal vascular attenuation was found in both the DM and DM-ERCM groups; however, was more severe in the DM group. On histology, the ganglion cell and nerve fiber layer rates of the total retinal layer significantly increased in the DM group compared with the Con group, whereas the DM-ERCM group showed no significant difference compared with the Con group. Cataracts progressed significantly more in the DM group than that in the DM-ERCM group and there was no uveitis in the DM-ERCM group. Conclusions: Subconjunctival ERCM delayed the progression of DR and cataracts and significantly reduced the incidence of uveitis. Translational Relevance: Our study shows the clinical potential of minimally invasive exosome-rich conditioned medium treatment to prevent diabetic retinopathy.

Digital cognitive behavioral therapy for insomnia on depression and anxiety: a systematic review and meta-analysis.

Despite research into the development of digital cognitive behavioral therapy for insomnia (dCBT-I), research into the outcomes of dCBT-I on insomnia and the associated clinical conditions of depression and anxiety have been limited. The PubMed, PsycINFO (Ovid), Embase, and Cochrane databases were searched for randomized controlled trials (RCTs) on adult patients with insomnia also having reported measures of depressive or anxiety symptoms. In total, 2504 articles were identified after duplicate removal, and 22 RCTs were included in the final meta-analysis. At the post-treatment assessment, the dCBT-I group had a small to moderate effect in alleviating depressive (standardized mean difference (SMD) = -0.42; 95% CI: -0.56, -0.28; p < 0.001; k = 21) and anxiety symptoms (SMD = -0.29; 95% CI: -0.40, -0.19; p < 0.001; k = 18), but had a large effect on sleep outcome measures (SMD = -0.76; 95% CI: -0.95, -0.57; p < 0.001; k = 22). When considering treatment adherence, the treatment effects of those in the high adherent groups identified a more robust outcome, showing greater effect sizes than those in the low adherent groups for depression, anxiety, and sleep outcomes. Furthermore, additional subgroup analysis on studies that have used the fully automated dCBT-I treatment without the support of human therapists reported significant treatment effects for depression, anxiety, and sleep outcomes. The results demonstrated that digital intervention for insomnia yielded significant effects on alleviating depressive and anxiety symptoms as well as insomnia symptoms. Specifically, the study demonstrated significant effects on the above symptoms when considering treatment adherence and implementing fully automated dCBT-I.

Impact of data extraction errors in meta-analyses on the association between depression and peripheral inflammatory biomarkers: an umbrella review.

BACKGROUND: Accumulating evidence suggests that alterations in inflammatory biomarkers are important in depression. However, previous meta-analyses disagree on these associations, and errors in data extraction may account for these discrepancies. METHODS: PubMed/MEDLINE, Embase, PsycINFO, and the Cochrane Library were searched from database inception to 14 January 2020. Meta-analyses of observational studies examining the association between depression and levels of tumor necrosis factor-α (TNF-α), interleukin 1-ß (IL-1ß), interleukin-6 (IL-6), and C-reactive protein (CRP) were eligible. Errors were classified as follows: incorrect sample sizes, incorrectly used standard deviation, incorrect participant inclusion, calculation error, or analysis with insufficient data. We determined their impact on the results after correction thereof. RESULTS: Errors were noted in 14 of the 15 meta-analyses included. Across 521 primary studies, 118 (22.6%) showed the following errors: incorrect sample sizes (20 studies, 16.9%), incorrect use of standard deviation (35 studies, 29.7%), incorrect participant inclusion (7 studies, 5.9%), calculation errors (33 studies, 28.0%), and analysis with insufficient data (23 studies, 19.5%). After correcting these errors, 11 (29.7%) out of 37 pooled effect sizes changed by a magnitude of more than 0.1, ranging from 0.11 to 1.15. The updated meta-analyses showed that elevated levels of TNF- α, IL-6, CRP, but not IL-1ß, are associated with depression. CONCLUSIONS: These findings show that data extraction errors in meta-analyses can impact findings. Efforts to reduce such errors are important in studies of the association between depression and peripheral inflammatory biomarkers, for which high heterogeneity and conflicting results have been continuously reported.

Two cases of ectopic dirofilariasis by Dirofilaria immitis in subconjunctival and subcutaneous tissues in dogs.

We report two cases of ectopic dirofilariasis caused by Dirofilaria immitis in the subconjunctival and subcutaneous tissues of dogs. In Case 1, a 10-year-old female poodle suffered from a subconjunctival mass in the left eye that was refractory to antibiotic and steroid treatments. The mass was removed surgically, and a whitish nematode was identified within the mass. In Case 2, a stray 3-year-old male greyhound was rescued and transferred to a local veterinary hospital. During care, two nematodes were observed on the left hind paw and leg. The observed worms were not typical of D. immitis; therefore, the species was confirmed using molecular methods. Phylogenetic analysis revealed high genetic identity with other previously reported D. immitis strain. Subcutaneous and subconjunctival dirofilariasis have been mainly caused by D. repens. To the best of our knowledge, this is the first report of subconjunctival ectopic dirofilariasis by D. immitis in a dog, and the first report of subcutaneous localization in Korea. Therefore, in endemic regions, ectopic dirofilariasis caused by D. immitis should be considered as a differential diagnosis in subconjunctival and subcutaneous masses.

Initial Healing Effects of Platelet-Rich Plasma (PRP) Gel and Platelet-Rich Fibrin (PRF) in the Deep Corneal Wound in Rabbits.

Platelet concentrates (PCs), including platelet-rich plasma (PRP) gel and platelet-rich fibrin (PRF), are autologous blood-derived biomaterials containing numerous growth factors. This study aimed to evaluate the initial healing effects of PRP gel and PRF on deep corneal wounds. Thirty-three eyes from New Zealand white rabbits were divided into four groups: group 1, lamellar keratectomy (LK); group 2, LK + commercial porcine small intestinal submucosal membrane (SIS); group 3, LK + SIS + PRP gel; and group 4, LK + SIS + PRF. Postoperative clinical and histological findings were observed for eight weeks. Group 1 showed no neovascularization during the observation period, and incompletely recovered with a thin cornea. Group 2 showed active healing through neovascularization, and a thick cornea was regenerated through the sufficient generation of myofibroblasts. Although group 3 showed a healing effect similar to that of group 2, angiogenesis and subsequent vessel regression were promoted, and corneal opacity improved more rapidly. In group 4, angiogenesis was promoted during initial healing; however, the incidence of complications, such as inflammation, was high, and myofibroblasts were hardly generated in the corneal stroma, which adversely affected remodeling. In conclusion, while PRP gel is a safe surgical material for promoting remodeling through vascular healing and myofibroblast production in deep corneal wounds, the use of PRF is not recommended.

Prediction of good sleep with physical activity and light exposure: a preliminary study.

STUDY OBJECTIVES: Cognitive behavioral treatment for insomnia is performed under the premise that feedback provided by evaluation of sleep diaries written by patients will result in good sleep. The sleep diary is essential for behavior therapy and sleep hygiene education. However, limitations include subjectivity and laborious input. We aimed to develop an artificial intelligence sleep prediction model and to find factors associated with good sleep using a wrist-worn actigraphy device. METHODS: We enrolled 109 participants who reported having no sleep disturbances. We developed a sleep prediction model using 733 days of actigraphy data of physical activity and light exposure. Twenty-four sleep prediction models were developed based on different data sources (actigraphy alone, sleep diary alone, or combined data), different durations of data (1 or 2 days), and different analysis methods (extreme gradient boosting, convolutional neural network, long short-term memory, logistic regression analysis). The outcome measure of "good sleep" was defined as ≥ 90% sleep efficiency. RESULTS: Actigraphy model performance was comparable to sleep diary model performance. Two-day models generally performed better than 1-day models. Among all models, the 2-day, combined (actigraphy and sleep diary), extreme gradient boosting model had the best performance for predicting good sleep (accuracy = 0.69, area under the curve = 0.70). CONCLUSIONS: The findings suggested that it is possible to develop automated sleep models with good predictive performance. Further research including patients with insomnia is needed for clinical application. CITATION: Park KM, Lee SE, Lee C, et al. Prediction of good sleep with physical activity and light exposure: a preliminary study. J Clin Sleep Med. 2022;18(5):1375-1383.

Sex-specific association of hair cortisol concentration with stress-related psychological factors in healthy young adults.

BACKGROUND: Hair cortisol concentration (HCC) has received attention as a useful marker of stress, but evidence on associations between psychological factors and cortisol concentration is inconsistent. The purpose of this study was to investigate the sex differences in the relationship between cortisol concentration and psychological factors in healthy young adults. METHODS: A total of 205 (103 females, 102 males) healthy young adults participated. HCC and various stress-related psychological measures were compared between sexes. Multiple linear regression analyses were performed to assess associations between HCC and stress-related psychological measures for all participants and for each sex. RESULTS: The difference in HCC according to sex was not significant. The reported number of stressful life events in the past year, stress perception, depressive and anxiety-related symptoms, and emotion dysregulation were not different between sexes, either. The association between HCC and emotion dysregulation was significant in females but not males. CONCLUSION: We observed a sex-specific association between HCC and psychological factors. Our findings may imply that HCC could be a useful biomarker of stress and stress-related emotion dysregulation in healthy young women.

Effect of Childhood Trauma on the Association Between Stress-Related Psychological Factors and Hair Cortisol Level in Young Adults.

OBJECTIVE: Relationship between hair cortisol concentration (HCC) and stress-related psychological measures are inconclusive, possibly due to overlooked heterogeneity regarding childhood trauma and a lack of comprehensive research on stress-related psychological factors. This study aims to compare young adults without history of childhood trauma to young adults who experienced childhood trauma using HCC and various stress-related psychological factors, as well as investigate the impacts of childhood trauma on the association between HCC and stress-related psychological measures. METHODS: A total of 206 young, healthy adults were recruited. We divided participants into two groups depending on whether or not they had suffered moderate-to-severe childhood trauma (CT+ and CT-) and compared HCC and various stress-related psychological measures between groups. Using multiple linear regression analyses, we assessed the associations between HCC and stress-related psychological measures for each group. RESULTS: We found no difference between the groups in HCC or the reported number of stressful life events in the past year; however, CT+ individuals reported higher stress perception, more depressive and anxiety-related symptoms, and more difficulties in emotion regulation than CT- individuals. HCC was associated with emotion dysregulation among the CT- individuals, but not among the CT+ individuals. CONCLUSION: These findings suggest that history of childhood trauma should be considered in studies using HCC as a biomarker for stress in young adults. Furthermore, HCC might be a useful biomarker of stress and stress-related emotion dysregulation in individuals without moderate-to-severe childhood trauma.

Shame and guilt in youth at ultra-high risk for psychosis.

OBJECTIVE: Feelings of shame and guilt have rarely been investigated in people at ultra-high risk (UHR) for psychosis. We aimed to outline differences in shame and guilt in relation to empathy and theory of mind (ToM) in young people, particularly those at UHR for psychosis. METHODS: First, 166 young healthy controls were assessed for their proneness to shame and guilt using the Test of Self-Conscious Affect, empathy and its four subdomains (perspective taking, fantasy, empathic concern, and personal distress) using the Interpersonal Reactivity Index (IRI), ToM using the ToM picture stories task, and neurocognitive performance using the Raven's Standard Progressive Matrices (SPM). Next, we evaluated shame and guilt in 24 UHR individuals comparing them to 24 age- and sex-matched healthy controls. Finally, we explored relationships for shame and guilt in relation to empathy and ToM in the UHR individuals. RESULTS: In the healthy youth, a regression analysis showed fantasy and personal distress in IRI to be significant determinants of shame, while perspective taking and empathic concern in IRI, ToM, and SPM were independent predictors of guilt. Meanwhile, compared to the healthy controls, individuals with UHR exhibited higher levels of shame, which was associated with increased personal distress. DISCUSSION: Our findings showed that four subdomains of empathy, ToM, and neurocognition were differentially associated with shame and guilt in healthy young people. Given the correlation between excessive feelings of shame and high levels of the personal distress dimension of empathy in UHR for psychosis, redressing the tendency to focus on self-oriented negative emotions upon witnessing distress of others could possibly reduce self-blame or self-stigma of help-seeking individuals.

First Clinical Cases of Spirometrosis in Two Cats in Korea.

This study reports the first two clinical cases of spirometrosis caused by Spirometra sp. in cats in Korea. In these two cases, the cats vomited, and long proglottids of tapeworm were recovered. The sick cats presented with anorexia and lethargy. However, they unexpectedly showed no diarrhea, which is the main symptom of spirometrosis. Based on a fecal floatation test as well as morphological and molecular analyses, the parasite was diagnosed as Spirometra sp. The 2 cases were treated with praziquantel. This study suggests regular monitoring of health and deworming in companion animals, even when animals are well cared for, with regular preventive medication. Additionally, spirometrosis should be considered in the differential diagnosis in cases of gastrointestinal symptoms in Spirometra endemic areas.

Custom-made artificial eyes using 3D printing for dogs: A preliminary study.

Various incurable eye diseases in companion animals often result in phthisis bulbi and eye removal surgery. Currently, the evisceration method using silicone balls is useful in animals; however, it is not available to those with impaired cornea or severe ocular atrophy. Moreover, ocular implant and prostheses are not widely used because of the diversity in animal size and eye shape, and high manufacturing cost. Here, we produced low-cost and customized artificial eyes, including implant and prosthesis, using computer-aided design and three-dimensional (3D) printing technique. For 3D modeling, the size of the artificial eyes was optimized using B-mode ultrasonography. The design was exported to STL files, and then printed using polycaprolactone (PCL) for prosthesis and mixture of PCL and hydroxyapatite (HA) for ocular implant. The 3D printed artificial eyes could be produced in less than one and half hour. The prosthesis was painted using oil colors and biocompatible resin. Two types of eye removal surgery, including evisceration and enucleation, were performed using two beagle dogs, as a preliminary study. After the surgery, the dogs were clinically evaluated for 6 months and then histopathological evaluation of the implant was done. Ocular implant was biocompatible and host tissue ingrowth was induced after in vivo application. The custom-made prosthesis was cosmetically excellent. Although long-term clinical follow-up might be required, the use of 3D printed-customized artificial eyes may be beneficial for animals that need personalized artificial eye surgery.

Tissue engineered ultra-thin descemet stripping corneal endothelial layers using porcine cornea and stem cells.

Due to their very poor proliferative capacity, the dysfunction of corneal endothelial cells can sometimes lead to incurable eye diseases that require corneal transplantation. Although many studies have been performed to reconstruct corneal endothelial cells, corneal transplantation is still considered to be the established approach. In this study, we developed bio-engineered Descemet stripping endothelial (DSE) layers, using porcine cornea and induced pluripotent stem cell (iPSC)-derived corneal endothelial cells (iCECs). First, we optimized a protocol to prepare an ultra-thin and decellularized Descemet stripping (DS) scaffold from porcine cornea. Our DS layers show over 90% transparency compared to the control. Porcine-derived cells and xenogenic antigens disappeared, whereas the collagen matrix remained in the graft. Next, corneal endothelial cell lines or iCECs were seeded on the decellularized DS graft and cultured for 7 days. The drying method reduced graft rolling and edema, and increased transparency during culture. The reseeded cells were evenly distributed over the graft, and most of the cells survived. Although future clinical studies are warranted, engineered DSE tissues using xenogenic tissues and stem cells will be useful tools for the treatment of incurable corneal diseases.

Decellularized hepatic extracellular matrix hydrogel attenuates hepatic stellate cell activation and liver fibrosis.

Liver fibrosis results from excessive accumulation of extracellular matrix (ECM) proteins that distort the hepatic architecture. Progression of liver fibrosis results in cirrhosis and liver failure, and often, liver transplantation is required. The decellularized liver tissue contains different components that mimic the natural hepatic environment. We hypothesized that a decellularized liver hydrogel can be used to replace the necrotic hepatocytes and damaged ECM. Therefore, our aim in this study is to develop a therapy for treating liver fibrosis. Mice livers were decellularized and processed to form a hepatic hydrogel. We evaluated the biocompatibility and bioactivity of the hydrogel. The ability of the hydrogel to enhance the migration of hepatocytes and endothelial cells was investigated. Human hepatic stellate cell line (LX-2) activated by transforming growth factor-ß1 (TGF-ß1) was used as in vitro model for fibrogenesis. Then, the hydrogel was injected into the liver parenchyma of mice after the induction of liver fibrosis using thioacetamide. The resulting hydrogel maintained a complex composition, which included glycosaminoglycans, collagen, elastin, and growth factors. Hepatocytes and endothelial cells were shown to migrate toward the hydrogel in vitro. Liver hydrogel improved TGF-ß1-induced LX-2 cells activation via blocking the TGF-ß1/Smad pathway. The matrix was delivered successfully in vivo and enhanced the reduction of fibrosis and recovery to a nearly normal structure. In conclusion, we have demonstrated that the liver hydrogel can be utilized as an injectable biomaterial for liver tissue engineering in order to reduce the degree of fibrosis.

Changes in resting-state brain connectivity following computerized cognitive behavioral therapy for insomnia in dialysis patients: A pilot study.

OBJECTIVE: Insomnia is prevalent among dialysis patients and affects their mortality. Although cognitive behavioral therapy for insomnia (CBTi) is recommended, attending regular face-to-face CBTi sessions is a major challenge for patients. We evaluated the effectiveness of a self-directed computerized CBTi (cCBTi) in dialysis patients, and investigated changes in resting-state brain connectivity and inflammatory cytokines following cCBTi. METHOD: Thirty-five patients undergoing maintenance hemodialysis or peritoneal dialysis who had insomnia were screened for participation in the study, with 17 participants included in the final analyses. A self-directed cCBTi protocol accessed via tablet computer during dialysis or at home was developed and applied. Information about sleep, anxiety, depression, laboratory data, and resting-state functional magnetic resonance imaging data was obtained 3-5 days before and after cCBTi. RESULTS: cCBTi improved sleep quality, and this was correlated with increased resting-state brain connectivity between the default-mode network and the premotor/dorsolateral prefrontal cortex. The decrement of interleukin-1ß levels were correlated with improved sleep quality and increased brain connectivity after cCBTi. CONCLUSION: Our pilot study findings suggest that cCBTi is effective for dialysis patients with insomnia, and the therapeutic effects of cCBTi are related to changes in brain functional connectivity and inflammatory cytokines.

Role of GRK6 in the Regulation of Platelet Activation through Selective G Protein-Coupled Receptor (GPCR) Desensitization.

Platelet G protein-coupled receptors (GPCRs) regulate platelet function by mediating the response to various agonists, including adenosine diphosphate (ADP), thromboxane A2, and thrombin. Although GPCR kinases (GRKs) are considered to have the crucial roles in most GPCR functions, little is known regarding the regulation of GPCR signaling and mechanisms of GPCR desensitization by GRKs in platelets. In this study, we investigated the functional role of GRK6 and the molecular basis for regulation of specific GPCR desensitization by GRK6 in platelets. We used GRK6 knockout mice to evaluate the functional role of GRK6 in platelet activation. Platelet aggregation, dense- and -granule secretion, and fibrinogen receptor activation induced by 2-MeSADP, U46619, thrombin, and AYPGKF were significantly potentiated in GRK6-/- platelets compared to the wild-type (WT) platelets. However, collagen-related peptide (CRP)-induced platelet aggregation and secretion were not affected in GRK6-/- platelets. Interestingly, platelet aggregation induced by co-stimulation of serotonin and epinephrine which activate Gq-coupled 5HT2A and Gz-coupled 2A adrenergic receptors, respectively, was not affected in GRK6-/- platelets, suggesting that GRK6 was involved in specific GPCR regulation. In addition, platelet aggregation in response to the second challenge of ADP and AYPGKF was restored in GRK6-/- platelets whereas re-stimulation of the agonist failed to induce aggregation in WT platelets, indicating that GRK6 contributed to P2Y1, P2Y12, and PAR4 receptor desensitization. Furthermore, 2-MeSADP-induced Akt phosphorylation and AYPGKF-induced Akt, extracellular signal-related kinase (ERK), and protein kinase Cδ (PKC) phosphorylation were significantly potentiated in GRK6-/- platelets. Finally, GRK6-/- mice exhibited an enhanced and stable thrombus formation after FeCl3 injury to the carotid artery and shorter tail bleeding times, indicating that GRK6-/- mice were more susceptible to thrombosis and hemostasis. We conclude that GRK6 plays an important role in regulating platelet functional responses and thrombus formation through selective GPCR desensitization.