Glycemic Control and Retinal Microvascular Changes in Type 2 Diabetes Mellitus Patients without Clinical Retinopathy.

Background: To investigate the association of glycemic control and retinal microvascular changes in patients with type 2 diabetes mellitus (T2DM) without diabetic retinopathy (DR). Methods: This retrospective, observational, cohort study included patients with T2DM without DR. The patients were categorized into intensive control (IC; mean glycosylated hemoglobin [HbA1c] ≤7.0%) and moderate control (MC; mean HbA1c >7.0%) groups. Optical coherence tomography (OCT) and swept-source OCT angiography (OCTA) image parameters were compared between three groups, including healthy controls. Results: In total, 259 eyes of 259 participants (88 IC, 81 MC, and 90 controls) were included. The foveal avascular zone area was significantly larger in the MC group than IC and control groups (all P<0.05). The IC group had lower vessel density in the superficial retinal layer and deep retinal layer than the controls (all P<0.05). The choriocapillaris (CC) flow deficit (FD) was significantly greater in the MC group than in the IC and control groups (18.2%, 16.7%, and 14.2%, respectively; all P<0.01). In multivariate regression analysis, CC-FD was associated with the mean HbA1c level (P=0.008). There were no significant differences in OCT parameters among the groups. Conclusion: OCTA revealed that early CC impairment is associated with HbA1c levels; the CC changes precede clinically apparent DR. The OCTA parameters differed among the groups according to the degree of glycemic control. Our results suggest that microvascular changes precede DR and are closely related to glycemic control.

Anti-thymocyte globulin-mediated immunosenescent alterations of T cells in kidney transplant patients.

Objectives: Kidney transplant (KT) is the most effective treatment for end-stage renal disease. The immunosuppressant anti-thymocyte globulin (ATG) has been applied for induction therapy to reduce the risk of acute transplant rejection for patients at high immunological risk. Despite its putative role in replicative stress during immune reconstitution, the effects of ATG on T-cell immunosenescent changes remain to be understood. Methods: Phenotypic and functional features of senescent T cells were examined by flow cytometry in 116 healthy controls (HC) and 95 KT patients for comparative analysis according to ATG treatment and CMV reactivation. The TCR repertoire was analysed in peripheral blood mononuclear cells (PBMCs) of KT patients. Results: T cells of KT patients treated with ATG (ATG+) show typical immunosenescent features, accumulation of CD28-, CD85j+ or CD57+ T cells, and imbalance of functional T-cell subsets, compared with untreated KT patients (ATG-). Plasma IL-15 and CMV-IgG levels were higher in KT patients than in HCs, and the IL-15 level positively correlated with the frequency of CD28- T cells in KT patients. ATG+ patients had a higher prevalence of CMV reactivation, which is associated with an increased frequency of CD28- T cells. As a result, ATG+ patients had expanded CMV-specific T cells and decreased TCR diversity. However, proliferation, cytokine-producing capacity and polyfunctionality of T cells were preserved in ATG+ patients. Conclusion: Our findings suggest that ATG treatment contributes to the accumulation of senescent T cells, which may have lifelong clinical implications in KT patients. Thus, these patients require long-term and comprehensive immune monitoring.

Properties and anti-inflammatory effects of Sargassum muticum enzymatic extracts decomposed using crude enzyme from Shewanella oneidensis PKA1008.

This study was conducted to investigate the general properties of an enzymatic extract of Sargassum muticum (SM) produced using a crude enzyme from Shewanella oneidensis PKA 1008 and their anti-inflammatory activities. The SM was mixed with crude enzymes from S. oneidensis PKA 1008 (1:1 (v/v)) and incubated at 30 °C for 0, 3, 6, 12, 24, 48, and 60 h. S. oneidensis PKA 1008 crude enzyme showed the highest SM enzymatic extracts degradation ability when reacted with SM for 48 h. These evaluations demonstrated a 134.25% increase in reducing sugar content and a 14.90% reduction in viscosity at 48 h. The pH, lightness (L*) and yellowness (b*) of the SM enzymatic extracts decreased significantly with increasing reaction time. Moreover, the SM enzymatic extracts demonstrated significant anti-inflammatory activity. These results indicate that the crude enzyme from S. oneidensis PKA 1008 can be used to enhance the polysaccharide degradation of SM, and the resultant oligosaccharides may have an anti-inflammatory effect.

Effects of Gamma Irradiation on Inhibition of Urease Activity and Fishy Smell in Mackerel (Scomber japonicus) during Refrigerated Storage.

In this study, gamma-irradiated mackerel (Scomber japonicus) meat was stored in a refrigerator for 20 days to examine the physicochemical changes related to fishy smell. The effect of gamma irradiation on the inhibition of the activity of crude urease extracted from Vibrio parahaemolyticus was also evaluated. Increased levels of trimethylamine (TMA) and volatile basic nitrogen (VBN) content, which are the main components causing fishy smell, were significantly reduced by day 20 of storage after gamma irradiation, indicating that freshness was maintained during storage. The ammonia nitrogen contents of 3, 7, 10, and 20 kGy gamma-irradiated groups were significantly decreased by 6.5, 15.2, 17.4, and 23.9%, respectively, compared to non-irradiated groups on day 20 of storage. In addition, urease activity decreased in a gamma irradiation intensity-dependent manner. Volatile organic compounds (VOCs) were measured during the storage of gamma-irradiated mackerel meat. The contents of ethanol, 2-butanone, 3-methylbutanal, and trans-2-pentenal, which are known to cause off-flavors due to spoilage of fish, were significantly reduced by day 20 of storage. Therefore, gamma irradiation can be considered useful for inhibiting urease activity and reducing fishy smell during fish storage.

Effect of High Hydrostatic Pressure Treatment on Urease Activity and Inhibition of Fishy Smell in Mackerel (Scomber japonicus) during Storage.

In this study, the physicochemical changes related to fishy smell were determined by storing high hydrostatic pressure (HHP)-treated mackerel (Scomber japonicus) meat in a refrigerator for 20 days. The inhibition of crude urease activity from Vibrio parahaemolyticus using HHP treatment was also investigated. The mackerel meat storage experiment demonstrated that production of trimethylamine (TMA) and volatile basic nitrogen (VBN), the main components of fishy smell, was significantly reduced on the 20th day of storage after the HHP treatment compared to the untreated mackerels. The results demonstrated that the increased ammonia nitrogen rates in the 2000, 3000, and 4000 bar, HHP-treated groups decreased by 23.8%, 23.8%, and 31.0%, respectively, compared to the untreated groups. The enzyme activity of crude urease was significantly reduced in the HHP-treated group compared to that in the untreated group. Measurement of the volatile organic compounds (VOCs) in mackerel meat during storage indicated that the content of ethanol, 2-butanone, 3-methylbutanal, and trans-2-pentenal, which are known to cause off-flavor due to spoilage, were significantly reduced by HHP treatment. Collectively, our results suggested that HHP treatment would be useful for inhibiting the activity of urease, thereby reducing the fishy smells from fish and shellfish.

Improving enzyme activity, thermostability and storage stability of ß-1,3-1,4-glucanase with poly-γ-glutamic acid produced by Bacillus sp. SJ-10.

ß-1,3-1,4-glucanase (BG) is an industrially important enzyme owing to its stringent specificity for ß-glucan cleavage. In this study, poly-γ-glutamic acid (γ-PGA) was added to BG to investigate its effect on improving the activity and stability of the enzyme. The effect of γ-PGA was investigated by analyzing kinetic and thermodynamic parameters. Compared to control, significant differences (P < .05) in enzyme activity were observed when 1.0 %, 1.5 %, and 2.0 % γ-PGA was added, and the activities were increased 1.23 ±â€¯0.05, 1.23 ±â€¯0.07, and 1.31 ±â€¯0.07-fold, respectively. Regarding thermostability, residual BG activity after a 1 h incubation at 60 °C was 12.53 ±â€¯0.06 % without γ-PGA and 79.02 ±â€¯5.76 % with 1% γ-PGA. The storage stability at 25 °C and 50 °C also increased when γ-PGA was present. The kinetics and thermodynamic investigations indicated that the increased activity and stability of BG when γ-PGA was added were due to increased values of the Vmax, Kcat, and activation energy for denaturation. The findings of this study suggest that adding γ-PGA to BG increases the application value of this enzyme in the food and feed industries.

Indoxyl Sulfate-Mediated Metabolic Alteration of Transcriptome Signatures in Monocytes of Patients with End-Stage Renal Disease (ESRD).

End-stage renal disease (ESRD) is the final stage of chronic kidney disease, which is increasingly prevalent worldwide and is associated with the progression of cardiovascular disease (CVD). Indoxyl sulfate (IS), a major uremic toxin, plays a key role in the pathology of CVD via adverse effects in endothelial and immune cells. Thus, there is a need for a transcriptomic overview of IS responsive genes in immune cells of ESRD patients. Here, we investigated IS-mediated alterations in gene expression in monocytes from ESRD patients. Transcriptomic analysis of ESRD patient-derived monocytes and IS-stimulated monocytes from healthy controls was performed, followed by analysis of differentially expressed genes (DEGs) and gene ontology (GO). We found that 148 upregulated and 139 downregulated genes were shared between ESRD patient-derived and IS-stimulated monocytes. Interaction network analysis using STRING and ClueGo suggests that mainly metabolic pathways, such as the pentose phosphate pathway, are modified by IS in ESRD patient-derived monocytes. These findings were confirmed in IS-stimulated monocytes by the increased mRNA expression of genes including G6PD, PGD, and TALDO1. Our data suggest that IS causes alteration of metabolic pathways in monocytes of ESRD patients and, thus, these altered genes may be therapeutic targets.

Immunosenescent characteristics of T cells in young patients following haploidentical haematopoietic stem cell transplantation from parental donors.

OBJECTIVES: Paediatric and adolescent patients in need of allogeneic haematopoietic stem cell transplantation (HSCT) generally receive stem cells from older, unrelated or parental donors when a sibling donor is not available. Despite encouraging clinical outcomes, it has been suggested that immune reconstitution accompanied by increased replicative stress and a large difference between donor and recipient age may worsen immunosenescence in paediatric recipients. METHODS: In this study, paired samples were collected at the same time from donors and recipients of haploidentical haematopoietic stem cell transplantation (HaploSCT). We then conducted flow cytometry-based phenotypic and functional analyses and telomere length (TL) measurements of 21 paired T-cell sets from parental donors and children who received T-cell-replete HaploSCT with post-transplant cyclophosphamide (PTCy). RESULTS: Senescent T cells, CD28- or CD57+ cells, were significantly expanded in patients. Further, not only CD4+CD28- T cells, but also CD4+CD28+ T cells showed reduced cytokine production capacity and impaired polyfunctionality compared with parental donors, whereas their TCR-mediated proliferation capacity was comparable. Of note, the TL in patient T cells was preserved, or even slightly longer, in senescent T cells compared with donor cells. Regression analysis showed that senescent features of CD4+ and CD8+ T cells in patients were influenced by donor age and the frequency of CD28- cells, respectively. CONCLUSION: Our data suggest that in paediatric HaploSCT, premature immunosenescent changes occur in T cells from parental donors, and therefore, long-term immune monitoring should be conducted.

Effect of Polar Amino Acid Residue Substitution by Site-Directed Mutagenesis in the N-terminal Domain of Pseudomonas sp. Phytase on Enzyme Activity.

The N-terminal domain of the Pseudomonas sp. FB15 phytase increases low-temperature activity and catalytic efficiency. In this study, the 3D structure of the N-terminal domain was predicted and substitutions for the amino acid residues of the region assumed to be the active site were made. The activity of mutants, in which alanine (A) was substituted for the original residue, was investigated at various temperatures and pH values. Significant differences in enzymatic activity were observed only in mutant E263A, suggesting that the amino acid residue at position 263 of the N-terminal domain is important in enzyme activity.

Osteoarthritis Affects Health-Related Quality of Life in Korean Adults with Chronic Diseases: The Korea National Health and Nutritional Examination Surveys 2009-2013.

BACKGROUND: Osteoarthritis (OA) is a chronic disease that commonly afflicts the elderly. This disease reduces the health-related quality of life (HRQoL) and causes a significant social burden. Whether the effect of coexisting chronic conditions on HRQoL varies according to the presence of OA remains unclear. Therefore, this study aimed to investigate this notion. METHODS: A total of 13,395 participants were identified from the 2009-2013 Korean National Health and Nutrition Examination Survey for analysis. HRQoL was assessed using the European quality of life-5 dimensions (EQ-5D) index. Patients with OA were defined as those diagnosed by a physician or those who displayed both, symptoms and radiological findings consistent with OA at the time of the survey. Associations between OA and 8 chronic conditions were tested using regression analysis. RESULTS: The EQ-5D index was lower in patients with OA than in those without (mean difference, -0.145; 95% confidence interval [CI], -0.138 to -0.151; P<0.001). Most patients with OA and chronic conditions showed a lower score than those without. EQ-5D was particularly lower in OA patients with hypertension, dyslipidemia, stroke, and renal failure. The estimated ß coefficient for the interaction term was significant in renal failure (-0.034; 95% CI, -0.055 to -0.012), after adjusting for demographic and socio-economic variables. CONCLUSION: OA significantly affects HRQoL of Korean elderly individuals alone or when combined with other conditions. OA combined with renal failure is particularly detrimental. These results indicate the importance of managing OA, which is an underestimated disease in public health surveys.

Elderly Patients Exhibit Stronger Inflammatory Responses during Gout Attacks.

Gout attacks are often accompanied by systemic inflammatory response. The aim of the retrospective study was to compare gout patients in different age groups in terms of their clinical features at gout attacks. Patients, who were treated for gout attack in two tertiary medical centers between January 2000 and April 2014, were divided into young (≤ 50 years), middle-aged, and elderly (> 65 years) groups. Patients in three age groups were compared in terms of presence of fever (> 37.8°C), C-reactive protein (CRP) levels, and erythrocyte sedimentation ratio (ESR) at the gout attacks. Monocytes, which were isolated from 10 consecutive patients who previously experienced gout attacks, were stimulated with monosodium urate (MSU) crystals and cytokine production was measured by flow cytometry. Among 254 patients analyzed in this study, 48 were young, 65 were middle-aged, and 141 were elderly. The elderly patients were more likely to have fever (51.1%) during the attack than the young (20.8%) and middle-aged (30.8%) patients (P < 0.001 by χ² test). They were also more likely to have higher ESR and CRP levels than the young patients (P = 0.002 for ESR, P < 0.001 for CRP). Patients' age correlated significantly with CRP and ESR levels (both P < 0.001). After stimulation with MSU, the production of interleukin-1ß by monocytes increased with patients' age (r = 0.670, P = 0.03). In conclusion, gout attacks in elderly patients are associated with fever and higher ESR and CRP levels, often resembling a septic arthritis.

Indoxyl sulfate (IS)-mediated immune dysfunction provokes endothelial damage in patients with end-stage renal disease (ESRD).

Progressive renal failure causes uremia-related immune dysfunction, which features a chronic inflammatory milieu. Given the central role of end-stage renal disease (ESRD)-related immune dysfunction in the pathogenesis of cardiovascular diseases (CVDs), much attention has been focused on how uremic toxins affect cellular immunity and the mechanisms underlying pathogenesis of atherosclerosis in ESRD patients. Here, we investigated the characteristics of monocytes and CD4+ T cells in ESRD patients and the immune responses induced by indoxyl sulfate (IS), a key uremic toxin, in order to explore the pathogenic effects of these cells on vascular endothelial cells. In ESRD patients, monocytes respond to IS through the aryl hydrocarbon receptor (AhR) and consequently produce increased levels of TNF-α. Upon stimulation with TNF-α, human vascular endothelial cells produce copious amounts of CX3CL1, a chemokine ligand of CX3CR1 that is highly expressed on CD4+CD28-T cells, the predominantly expanded cell type in ESRD patients. A migration assay showed that CD4+CD28- T cells were preferentially recruited by CX3CL1. Moreover, activated CD4+CD28- T cells exhibited cytotoxic capability allowing for the induction of apoptosis in HUVECs. Our findings suggest that in ESRD, IS-mediated immune dysfunction may cause vascular endothelial cell damage and thus, this toxin plays a pivotal role in the pathogenesis of CVD.

Efficacy of Carboxymethylcellulose and Hyaluronate in Dry Eye Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: The efficacy of two artificial tears, carboxymethylcellulose (CMC) and hyaluronate (HA), was compared in the treatment of patients with dry eye disease. METHODS: We conducted a systematic review and meta-analysis on randomized controlled trials in the PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases. The efficacy was compared in terms of the mean change from baseline in tear break-up time. The meta-analysis was conducted using both random and fixed effect models. The quality of the selected studies was assessed for risk of bias. RESULTS: Five studies were included involving 251 participants. Random effect model meta-analysis showed no significant difference between CMC and HA in treating dry eye disease (pooled standardized mean difference [SMD]=-0.452; 95% confidence interval [CI], -0.911 to 0.007; P=0.053). In contrast, fixed effect model meta-analysis revealed significant improvements in the CMC group when compared to the HA group (pooled SMD=-0.334; 95% CI, -0.588 to -0.081; P=0.010). CONCLUSION: The efficacy of CMC appeared to be better than that of HA in treating dry eye disease, although meta-analysis results were not statistically significant. Further research is needed to better elucidate the difference in efficacy between CMC and HA in treating dry eye disease.

Unusual CD4+CD28- T Cells and Their Pathogenic Role in Chronic Inflammatory Disorders.

CD28 is a primary co-stimulatory receptor that is essential for successful T cell activation, proliferation, and survival. While ubiquitously expressed on naive T cells, the level of CD28 expression on memory T cells is largely dependent on the T-cell differentiation stage in humans. Expansion of circulating T cells lacking CD28 was originally considered a hallmark of age-associated immunological changes in humans, with a progressive loss of CD28 following replicative senescence with advancing age. However, an increasing body of evidence has revealed that there is a significant age-inappropriate expansion of CD4+CD28- T cells in patients with a variety of chronic inflammatory diseases, suggesting that these cells play a role in their pathogenesis. In fact, expanded CD4+CD28- T cells can produce large amounts of proinflammatory cytokines such as IFN-γ and TNF-α and also have cytotoxic potential, which may cause tissue damage and development of pathogenesis in many inflammatory disorders. Here we review the characteristics of CD4+CD28- T cells as well as the recent advances highlighting the contribution of these cells to several disease conditions.