Therapeutic Effects of Amnion-Conjugated Chitosan-Alginate Membranes on Diabetic Wounds in an Induced Diabetic Swine Model: An In Vitro and In Vivo Study.

Background Chitosan (CS) is a well-known antimicrobial dressing material. Moreover, widely used amniotic membranes contain growth factors beneficial for wound healing. Herein, we created a novel amnion-conjugated CS-alginate membrane dressing and tested its wound healing potency in a diabetic swine model. Methods The bovine amniotic powder growth factor contents were evaluated by protein assay, and the powder's wound healing effects were assessed in vitro by HaCaT cell scratch closure. In vivo, two minipigs developed streptozotocin-induced diabetes. Serial serum glucose measurements and intravenous glucose tolerance tests were performed to confirm their diabetic status. Twelve square-shaped wounds created on each pig's back were randomly divided into control ( n = 4), CS ( n = 4), and amnion-CS (AC; n = 4) groups and treated accordingly with different dressings. Wound healing in each group was assessed by measuring wound contraction over time, capturing wound perfusion with indocyanine green (ICG) angiography, and histologically analyzing inflammatory markers. Results Amniotic powder elution promoted HaCaT cell migration in the scratch wound model, suggesting its beneficial in vitro wound healing effects. In vivo, the CS and AC groups showed earlier wound contraction initiation and reepithelialization and earlier wound perfusion improvement by ICG angiography than the control group. Additionally, the wound size of the AC group at week 3 was significantly smaller than those in the control group. There was no significant difference in the numbers of acute and chronic inflammatory cells between the groups. Conclusion The amnion-conjugated CS-alginate membrane, as well as CS dressing alone, could be a favorable dressing option for diabetic wounds.

Smart Microneedles with Porous Polymer Layer for Glucose-Responsive Insulin Delivery.

A closed-loop system imitating the function of pancreatic cells, connected to microneedles (MNs) that automatically "release" insulin in response to the blood glucose (BG) levels would be highly satisfactory for improving the quality of life and health for diabetes patients. This paper describes an easy, fast and simple technique of coating a porous polymer layer on stainless steel (SS) MNs that release insulin in a glucose-responsive fashion. It was fabricated by sealing insulin, sodium bicarbonate (a pH-sensitive element [NaHCOз]) and glucose oxidase (glucose-specific enzymes [GOx]) into the pores of a porous polymer coating. Glucose can passively diffuse into the pores and become oxidized to gluconic acid by GOx, thereby causing a decrease in local pH. The subsequent reaction of protons with NaHCOз forms carbon dioxide (CO2) which creates pressure inside the pores, thereby rupturing the thin polymer film and releasing the encapsulated insulin. Field emission scanning electron microscopy (FE-SEM) images displayed that upon the exposure of MNs to glucose-free phosphate buffer saline (PBS) with pH 7.4, the pores of the porous MNs were closed, while in MNs exposed to a hyperglycemic glucose level, the pores were opened and the thin film burst. These MNs demonstrated both in vitro (in porcine skin and PBS) and in vivo (in diabetic rats) glucose-mediated insulin release under hyperglycemic conditions with rapid responsiveness. This study validated that the release of insulin from porous MNs was effectively correlated with glucose concentration.

Prediction of drug-induced immune-mediated hepatotoxicity using hepatocyte-like cells derived from human embryonic stem cells.

Drug-induced liver injury (DILI) is a leading cause of liver disease and a key safety factor during drug development. In addition to the initiation events of drug-specific hepatotoxicity, dysregulated immune responses have been proposed as major pathological events of DILI. Thus, there is a need for a reliable cell culture model with which to assess drug-induced immune reactions to predict hepatotoxicity for drug development. To this end, stem cell-derived hepatocytes have shown great potentials. Here we report that hepatocyte-like cells derived from human embryonic stem cells (hES-HLCs) can be used to evaluate drug-induced hepatotoxic immunological events. Treatment with acetaminophen significantly elevated the levels of inflammatory cytokines by hES-HLCs. Moreover, three human immune cell lines, Jurkat, THP-1, and NK92MI, were activated when cultured in conditioned medium obtained from acetaminophen-treated hES-HLCs. To further validate, we tested thiazolidinedione (TZD) class, antidiabetic drugs, including troglitazone withdrawn from the market because of severe idiosyncratic drug hepatotoxicity. We found that TZD drug treatment to hES-HLCs resulted in the production of pro-inflammatory cytokines and eventually associated immune cell activation. In summary, our study demonstrates for the first time the potential of hES-HLCs as an in vitro model system for assessment of drug-induced as well as immune-mediated hepatotoxicity.

Exosome-mediated activation of toll-like receptor 3 in stellate cells stimulates interleukin-17 production by γδ T cells in liver fibrosis.

UNLABELLED: During liver injury, hepatocytes secrete exosomes that include diverse types of self-RNAs. Recently, self-noncoding RNA has been recognized as an activator of Toll-like receptor 3 (TLR3). However, the roles of hepatic exosomes and TLR3 in liver fibrosis are not yet fully understood. Following acute liver injury and early-stage liver fibrosis induced by a single or 2-week injection of carbon tetrachloride (CCl4 ), increased interleukin (IL)-17A production was detected primarily in hepatic γδ T cells in wild-type (WT) mice. However, liver fibrosis and IL-17A production by γδ T cells were both significantly attenuated in TLR3 knockout (KO) mice compared with WT mice. More interestingly, IL-17A-producing γδ T cells were in close contact with activated hepatic stellate cells (HSCs), suggesting a role for HSCs in IL-17A production by γδ T cells. In vitro treatments with exosomes derived from CCl4 -treated hepatocytes significantly increased the expression of IL-17A, IL-1ß, and IL-23 in WT HSCs but not in TLR3 KO HSCs. Furthermore, IL-17A production by γδ T cells was substantially increased upon coculturing with exosome-treated WT HSCs or conditioned medium from TLR3-activated WT HSCs. However, similar increases were not detected when γδ T cells were cocultured with exosome-treated HSCs from IL-17A KO or TLR3 KO mice. Using reciprocal bone marrow transplantation between WT and TLR3 KO mice, we found that TLR3 deficiency in HSCs contributed to decreased IL-17A production by γδ T cells, as well as liver fibrosis. CONCLUSION: In liver injury, the exosome-mediated activation of TLR3 in HSCs exacerbates liver fibrosis by enhancing IL-17A production by γδ T cells, which might be associated with HSC stimulation by unknown self-TLR3 ligands from damaged hepatocytes. Therefore, TLR3 might be a novel therapeutic target for liver fibrosis. (Hepatology 2016;64:616-631).

Mitochondrial Respiratory Defect Causes Dysfunctional Lactate Turnover via AMP-activated Protein Kinase Activation in Human-induced Pluripotent Stem Cell-derived Hepatocytes.

A defective mitochondrial respiratory chain complex (DMRC) causes various metabolic disorders in humans. However, the pathophysiology of DMRC in the liver remains unclear. To understand DMRC pathophysiology in vitro, DMRC-induced pluripotent stem cells were generated from dermal fibroblasts of a DMRC patient who had a homoplasmic mutation (m.3398T→C) in the mitochondrion-encoded NADH dehydrogenase 1 (MTND1) gene and that differentiated into hepatocytes (DMRC hepatocytes) in vitro. DMRC hepatocytes showed abnormalities in mitochondrial characteristics, the NAD(+)/NADH ratio, the glycogen storage level, the lactate turnover rate, and AMPK activity. Intriguingly, low glycogen storage and transcription of lactate turnover-related genes in DMRC hepatocytes were recovered by inhibition of AMPK activity. Thus, AMPK activation led to metabolic changes in terms of glycogen storage and lactate turnover in DMRC hepatocytes. These data demonstrate for the first time that energy depletion may lead to lactic acidosis in the DMRC patient by reduction of lactate uptake via AMPK in liver.

Prevention of post-stroke generalized anxiety disorder, using escitalopram or problem-solving therapy.

This study examined the efficacy of antidepressant treatment for preventing the onset of generalized anxiety disorder (GAD) among patients with recent stroke. Of 799 patients assessed, 176 were randomized, and 149 patients without evidence of GAD at the initial visit were included in this double-blind treatment with escitalopram (N=47) or placebo (N=49) or non-blinded problem-solving therapy (PST; 12 total sessions; N=53). Participants given placebo over 12 months were 4.95 times more likely to develop GAD than patients given escitalopram and 4.00 times more likely to develop GAD than patients given PST. Although these results should be considered preliminary, the authors found that both escitalopram and PST were effective in preventing new onset of post-stroke GAD.

Prevention of poststroke apathy using escitalopram or problem-solving therapy.

OBJECTIVE: Apathy occurs frequently following stroke and prior studies have demonstrated the negative effect of apathy on recovery from stroke. This study was a secondary analysis examining the efficacy of escitalopram, problem-solving therapy (PST), or placebo administered for 1 year to prevent the onset of apathy among patients with recent stroke. METHODS: Patients within 3 months of an index stroke who did not meet DSM-IV diagnostic criteria for major or minor depression and who did not have a serious comorbid physical illness were enrolled. Patients were recruited from three sites: University of Iowa, University of Chicago, and Burke Rehabilitation Hospital. One hundred fifty-four patients without evidence of apathy at initial evaluation were included in the randomized controlled trial using escitalopram (10 mg patients ≤65 years; 5 mg patients >65 years) (N = 51) or placebo (N = 47) or non-blinded PST (12 total sessions) (N = 56) over 1 year. At 3, 6, 9, and 12 months, patients were assessed for diagnosis and severity of apathy using the Apathy Scale. RESULTS: Using a Cox proportional hazards model of time to onset of apathy, participants given placebo were 3.47 times more likely to develop apathy than patients given escitalopram and 1.84 times more likely to develop apathy than patients given PST after controlling for age, sex, cognitive impairment, and diabetes mellitus status (adjusted hazard ratio: 3.47, 95% CI: 1.79-6.73 [escitalopram group]; adjusted hazard ratio: 1.84, 95% CI: 1.21-2.80 [PST group]). CONCLUSION: Escitalopram or PST was significantly more effective in preventing new onset of apathy following stroke compared with placebo.

Incident apathy during the first year after stroke and its effect on physical and cognitive recovery.

OBJECTIVE: This prospective study examined the course of cognitive, physical, and social impairment among patients who developed apathy during the first year after stroke. METHODS: Patients diagnosed with apathy (N = 23) were compared with patients who had no apathy (N = 33) at initial, 3, 6, 9, and 12 months after stroke for severity of global cognitive impairment as measured by Mini-Mental State Examination, severity of impairment in activities of daily living (ADLs) as measured by Functional Independence Measure, and severity of impairment in social functioning as measured by Social Functioning Exam. RESULTS: A total of 41.1% of patients met diagnostic criteria for apathy during the first year after stroke. The mean time from stroke to onset of apathy was 3.8 (3.3 SD) months and the mean duration was 5.6 (2.3 SD) months. Using a linear mixed model, after controlling for age, initial severity of impairment, and major depression, patients in the apathy group had significantly less recovery in cognition (t(149) = -2.06; p = 0.0411) and ADLs (t(104) = -3.37; p = 0.0011) during the first year after stroke compared with nonapathic patients. CONCLUSION: Apathy is common after stroke and leads to less recovery in cognition and ADLs over the first year after stroke compared with similar nonapathic patients.

Variations in the epigenetic regulation of lineage-specific genes among human pluripotent stem cell lines.

Pluripotent stem cells (PSCs) have unique transcriptional regulatory networks and epigenetic states that are involved in maintaining pluripotency. In this study, the transcriptional levels and histone modifications of lineage-specific genes were compared for human ESC (hESC) lines and human induced pluripotent stem cell (hiPSC) lines. Expression of the pluripotency marker genes, OCT4, SOX2, and NANOG, was largely modulated in hESCs by permissive histone marks, whereas hiPSC lines showed differential histone modifications in the gene promoters. The permissive histone mark, H3K4me3, predominantly contributed to expression of the oncogene, c-MYC, in hESC lines, whereas histone modifications of the c-MYC promoter varied between hiPSC lines. Interestingly, the transcriptional levels and epigenetic marks in the promoters of the developmental genes such as SOX17, T, and NESTIN varied among individual hiPSC lines. In particular, a partially-reprogrammed hiPSC cell line showed lower frequencies of permissive and repressive histone marks in the promoters of most genes, indicating incomplete epigenetic reprogramming. Our data indicate that respective hPSCs have distinct epigenetic signatures of lineage-specific genes, thereby leading to in their propensities to follow a particular differentiation pathway.

Increased frequency of first-episode poststroke depression after discontinuation of escitalopram.

BACKGROUND AND PURPOSE: The purpose of this study was to compare escitalopram, problem-solving therapy, and placebo to prevent poststroke depression during 6 months after discontinuation of treatment. METHODS: We examined for depression 33 patients assigned to placebo, 34 to escitalopram, and 41 to problem-solving therapy. RESULTS: After controlling for age, gender, prior mood disorder, and severity of stroke, new-onset major depression and Hamilton Depression scores were significantly higher 6 months after escitalopram was discontinued compared with the problem-solving therapy or placebo groups. CONCLUSIONS: Discontinuation of escitalopram may increase poststroke depressive symptoms.

Effect of antidepressants on the course of disability following stroke.

OBJECTIVE: Stroke often produces marked physical and cognitive impairments leading to functional dependence, caregiver burden, and poor quality of life. We examined the course of disability during a 1-year follow-up period after stroke among patients who were administered antidepressants for 3 months compared to patients given placebo for 3 months. METHODS: A total of 83 patients entered a double-blind randomized study of the efficacy of antidepressants to treat depressive disorders and reduce disability after stroke. Patients were assigned to either fluoxetine (N = 32), nortriptyline (N = 22) or placebo (N = 29). Psychiatric assessment included administration of the Present State Examination modified to identify DSM-IV symptoms of depression. The severity of depression was measured using the 17-item Hamilton Depression Rating Scale. The modified Rankin Scale was used to evaluate the disability of patients at initial evaluation and at quarterly follow-up visits for 1 year. Impairment in activities of daily living was assessed by Functional Independence Measure at the same time. RESULTS: During the 1-year follow-up period, and after adjusting for critical confounders including age, intensity of rehabilitation therapy, baseline stroke severity, and baseline Hamilton Depression Rating Scale, patients who received fluoxetine or nortriptyline had significantly greater improvement in modified Rankin Scale scores compared to patients who received placebo (t [156] = -3.17, p = 0.002). CONCLUSIONS: Patients treated with antidepressants had better recovery from disability by 1-year post stroke (i.e., 9 months after antidepressants were stopped) than patients who did not receive antidepressant therapy. This effect was independent of depression suggesting that antidepressants may facilitate the neural mechanisms of recovery in patients with stroke.

Epigenetic signatures and temporal expression of lineage-specific genes in hESCs during differentiation to hepatocytes in vitro.

Embryonic stem cells (ESCs) maintain unique epigenetic states to maintain their pluripotency. Differentiation of ESCs into specialized cell types requires changes in these epigenetic states. However, the dynamics of epigenetic marks found in hESCs during differentiation are poorly understood. Here, we report the variation in the dynamics of epigenetic modifications associated with the expression of lineage-specific genes during differentiation of hESCs to hepatocytes in vitro. The promoter regions of pluripotency marker genes characterized by permissive histone marks such as trimethylation of H3 at lysine 4 (H3K4me3) and acetylation of H3 at lysine 9 (H3K9ac) in hESCs were instead enriched with repressive histone marks such as dimethylation of H3 at lysine 9 (H3K9me2), trimethylation of H3 at lysine 9 (H3K9me3) and trimethylation of H3 at lysine 27 (H3K27me3) during differentiation to hepatocytes. Interestingly, expression of definitive endoderm marker genes containing bivalent and non-bivalent domains may be modulated by a marked reduction in H3K27me3 and a significant enhancement of permissive marks such as H3K4me3 and H3K9ac during hESC differentiation. Expression of hepatocyte marker genes regulated by histone modifications was similar to that of pluripotency marker genes. Our findings provide insight into the epigenetic mechanisms regulating expression of developmental genes. Of particular interest, they may be differentially regulated either in a bivalent or non-bivalent domain manner during hESC differentiation.

Efficient differentiation of human pluripotent stem cells into functional CD34+ progenitor cells by combined modulation of the MEK/ERK and BMP4 signaling pathways.

Differentiation of human pluripotent stem cells (hPSCs) into functional cell types is a crucial step in cell therapy. In the present study, we demonstrate that functional CD34(+) progenitor cells can be efficiently produced from human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) by combined modulation of 2 signaling pathways. A higher proportion of CD34(+) cells (∼ 20%) could be derived from hPSCs by inhibition of mitogen-activated protein kinase (MAPK) extracellular signal-regulated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling and activation of bone morphogenic protein-4 (BMP4) signaling. hPSC-derived CD34(+) progenitor cells further developed to endothelial and smooth muscle cells with functionality. Moreover, they contributed directly to neovasculogenesis in ischemic mouse hind limbs, thereby resulting in improved blood perfusion and limb salvage. Our results suggest that combined modulation of signaling pathways may be an efficient means of differentiating hPSCs into functional CD34(+) progenitor cells.

Therapist adherence to a motivational-interviewing intervention improves treatment entry for substance-misusing adolescents with low problem perception.

OBJECTIVE: This study evaluated whether adherence to the Strengths-Oriented Referral for Teens (SORT) model, a motivational interviewing (MI)-consistent intervention addressing ambivalence about attending treatment, positively predicted adolescents' initial-session attendance. METHOD: Therapist adherence was rated in 54 audiotaped SORT sessions by coders who were blind to treatment-entry status. Higher adherence scores reflected greater use of MI and solution focused language, discussion of client strengths, and dialogue with families on treatment need and options. RESULTS: Therapist adherence during adolescent segments interacted with adolescent problem perception. Predicted probabilities of attending initial sessions increased for low-problem-perception adolescents at increasingly higher therapist adherence. CONCLUSIONS: Although replication studies are needed, the SORT model of providing MI-consistent debriefing following initial assessments appears to be a promising approach for increasing treatment entry. Initial support for the treatment-matching hypothesis was found for substance-misusing adolescents contemplating treatment entry.

Iowa Case Management for Rural Drug Abuse.

OBJECTIVE: The purpose of this research was to evaluate the effectiveness of a comprehensive, strengths-based model of case management for clients in drug abuse treatment. METHOD: 503 volunteers from residential or intensive outpatient treatment were randomly assigned to one of three conditions of Iowa Case Management (ICM) plus treatment as usual (TAU), or to a fourth condition of TAU only. All were assessed at intake and followed at 3, 6, and 12 months. RESULTS: Clients in all four conditions significantly decreased substance use by 3 months after intake and maintained most gains over time. However, the addition of ICM to TAU did not improve substance use outcomes. CONCLUSION: Overall, the addition of case management did not significantly improve drug treatment as hypothesized by both researchers and clinicians. Some results were mixed, possibly due to the heterogeneous sample, wide range of case management activities, or difficulty retaining participants over time.

Substance abuse treatment with rural adolescents: issues and outcomes.

This study compared the characteristics and treatment outcomes of rural adolescents with urban adolescents in substance abuse treatment programs in CSAT's Strengthening Communities for Youth (SCY) initiative. Using data from ten SCY programs nationally, the authors classified adolescents as rural or urban using Rural-Urban Commuting Area (RUCA) codes. We then evaluated changes in substance use frequency and substance-related problems at three, six, and 12 months after baseline assessments for the two sites that treated rural (n = 59) and urban (n = 345) youth in outpatient settings. Data were analyzed using a two-part mixed effects model for zero-saturated dependent variables. At treatment intake, rural youth exhibited greater problem severity on a number of substance abuse and mental health indices. From intake to the 12-month follow-up point, the percentages of both urban and rural youth who reported abstinence increased significantly. Both rural and urban youth also reported fewer problems due to substance use over time, but differences between groups were not consistent. Overall, treatment appears equally effective for both rural and urban adolescents. As few rural youth obtained treatment, we encourage funding agencies and treatment providers to consider innovative ways for providing services in rural areas and addressing gaps in primary prevention, early identification, and continuing care.