Screening potential polyhydroxyalkanoate-producing bacteria from wastewater sludge.

We applied fluorescence staining of Nile red, polymerase chain reaction (PCR), and carbon substrate utilization and pressure tolerance analysis to execute three-stage screening for potential polyhydroxyalkanoate (PHA) producers in the sludge samples of 21 large-scale wastewater treatment plants of city and industrial parks in Taiwan area. Total 35,429 colonies were grown on 196 plates, the screened 30 strains were subjected to 16S rRNA analysis, and 18 identified genera belonged to Proteobacteria (67%), Firmicutes (17%), and Actinomycetota (16%). The PHA accumulation results revealed that nine genera (50% of 18 screened) produced PHAs by limiting the nitrogen source and excess single carbon sources of glucose in an aerobic status. The PHA accumulation percentage was 1.44-58.77% at dry cell weight, and the theoretical yield from glucose was 0.52-58.76%. Our results indicate that our triple-screening method is promising for identifying a high biodiversity of PHA-accumulating bacteria from activated sludge for future industrial applications.

Electro-catalytic Iodoplumbate Incorporating Two Types of Polymeric Anions.

The development of the most promising electro-catalysts for the high-performance hydrogen evolution reaction (HER) in neutral media is exceedingly desirable. Here, the convenient hydrothermal reaction of PbI2, 3-pyrazinyl-1,2,4-triazole (3-pt), KI, and methanol in HI aqueous solution acquired an organic hybrid iodoplumbate [mtp][Pb2I5][PbI3]·0.5H2O (denoted as PbI-1, mtp2+ = 3-(1,4-dimethyl-1H-1,2,4-triazol-4-ium-3-yl)-1-methylpyrazin-1-ium), which not only provided an infrequent in situ organic mtp2+ cation that originated from the hydrothermal N-methylation reaction of 3-pt in acidic KI solution but also offered the rare example of organic hybrid iodoplumbate incorporating both one-dimensional (1-D) [PbI3-]n and two-dimensional (2-D) [Pb2I5-]n polymeric anions with one configuration of the mtp2+ cation. PbI-1 was applied for the construction of a Ni nanoparticle decorating the PbI-1 electrode (Ni/PbI-1/NF) via successive coating and electrodeposition onto the porous Ni foam (NF) support. The fabricated Ni/PbI-1/NF electrode that served as the cathodic catalyst showed excellent HER electro-catalytic activity.

One-Dimensional Selenidostannates Based on an Infrequent Tetrameric Cluster [Sn4Se12] Exhibiting Electro-Catalytic Properties.

The discovery of low-cost and efficient electro-catalytic materials for hydrogen evolution reaction (HER) is very desirable in hydrogen energy technology. Here, a new type of one-dimensional (1-D) organic hybrid selenidostannate [Ni(en)3]n[Sn2Se5]n (SnSe-1, en = ethylenediamine) with an in situ [Ni(en)3]2+ complex was achieved by the solvothermal reaction of Sn, Se, and NiCl2·6H2O in a mixed solvent of en and triethanolamine at 160 °C for 10 days. The crystal structure of SnSe-1 contains a unique 1-D [Sn2Se52-]n chain built up from the sharing-edge connection of a hitherto-unknown tetrameric [Sn4Se12] cluster, which is separated by discrete [Ni(en)3]2+ complexes. SnSe-1 is first combined with Ni nanoparticles supported on conductive porous Ni foam (NF) to constitute a Ni/SnSe-1/NF electrode as the HER electro-catalyst, displaying superior electro-catalytic activity in near-neutral conditions.

Infrequent Cubane-Like Chromium Sulfide Cluster with σ-Donor Ligands with Efficient Electrocatalytic Property Toward Hydrogen Evolution Reaction.

The exploitation of efficient and economical electrocatalysts for hydrogen evolution reaction (HER) is of exceeding interest in renewable clean-energy technologies. Herein, the facile solvothermal reaction of S and chromic acetate in ethylenediamine (en) achieved a novel organic hybrid chromium sulfide [Cr4(µ3-S)4(en)4(SH)4]·0.25H2O (1), which offers a new type of antiferromagnetic cubane-like chromium sulfide cluster with σ-donor en ligands. 1 was utilized in combination with Ni nanoparticles and porous Ni foam (NF) to fabricate a Ni/1/NF electrode as an efficient cathodic catalyst, indicating excellent electrocatalytic property toward HER.

The optimal combination of Nile red identification, colony polymerase chain reaction, and gas chromatography detection methods in screening for polyhydroxyalkanoicate-producing bacteria.

The study devised a detection process combining Nile red-containing media, polymerase chain reaction (PCR), and gas chromatography (GC) to evaluate the possibility of microbes becoming polyhydroxyalkanoate (PHA) producers. The Nile red and PCR detection steps of designating PHA producers had true positive rates of 39.4% and 40%, respectively, and the use of GC analysis as the final step yielded accurate results for the production types and yields of PHAs. When the number of screening samples was up to 102, connecting all three inspection methods in tandem generated economic benefits. When up to 105 samples were screened, the use of all three detection methods reduced the cost to 3% of the cost and the time consumed 6% of using just Nile red plus GC or PCR plus GC. However, when the sum of samples exceeded 108, the cost of combining the three methods exceeds 1 million US dollars and was excessive; here, the combination of Nile red plus PCR could be considered, even though the true positive rate was only 30.7%.

One Luminescent Cadmium Iodide with Free Bifunctional Azole Sites as a Triple Sensor for Cu2+, Fe3+, and Cr2O72- Ions.

The exploration of an excellent triple sensor for monitoring Cu2+, Fe3+, and Cr2O72- ions is of exceeding significance because of their serious effects on the human body. Herein, optically active 1H-3,5-bis(pyrazinyl)-1,2,4-triazole (Hbpt) with triazolyl and pyrazinyl groups was applied for the construction of a new type of organic hybrid cadmium iodide [Cd6I8(bpt)4(H2O)4]·2H2O (1) incorporating a hitherto-unknown [Cd3I4(H2O)2]2+ trimeric-cationic unit, which shows an orange light emission at 589 nm with a large Stokes shift of 246 nm. In virtue of the existence of free bifunctional azole sites as the receptors, 1 exhibits a highly selective and sensitive sensing property toward Cu2+, Fe3+, and Cr2O72- ions in aqueous solution with lower detection limits of 0.70∼4.46 ppm, which offers the sole example of cadmium iodide as an excellent triple sensor for detecting Cu2+, Fe3+, and Cr2O72- ions. Moreover, temperature-dependent luminescent determinations also reveal that 1 can be used as the potential luminescent molecular thermometer.

Prognostic significance of soluble CD25 in patients with sepsis: a prospective observational study.

OBJECTIVES: The diagnosis of sepsis is challenging, the need for sensitive and specific diagnostic and prognostic biomarkers has not been met. Soluble CD25 (sCD25) is a readily available biomarker reported to represent the severity of the disease. This study aimed to assess the association between sCD25 and mortality in patients with sepsis. METHODS: In total, 329 adult patients with sepsis were screened through a prospective, observational study. We investigated the severity scores and sCD25 levels at admission to the intensive care unit (ICU), defined by sepsis (sepsis-3). The prognostic value of sCD25 was assessed using receiver operating characteristic (ROC) curves and binary logistic regression models in predicting unfavourable outcome. The correlations between variables and severity of disease were analysed by Spearman correlation tests. RESULTS: After entering the ICU, the sCD25 level and sequential organ failure assessment (SOFA) score were significantly higher in nonsurvivors than in survivors. The prognostic values estimated by the ROC curves were 0.678 for sCD25 and 0.945 for SOFA score at ICU admission. sCD25 had a modest ability to predict poor outcome. Logistic regression showed that increased levels of sCD25 were independently associated with unfavourable outcome. Spearman correlation tests showed that sCD25 levels were positively correlated with disease severity. CONCLUSIONS: In sepsis patients, increased sCD25 levels were independently associated with poor clinical outcomes. Further research is needed to improve the understanding of the pathophysiology of this relationship.

Effect of early restrictive fluid resuscitation on inflammatory and immune factors in patients with severe pelvic fracture.

PURPOSE: To study the effect of early restrictive fluid resuscitation (EFR) on inflammatory and immune factors in patients with severe pelvic fracture (SPF). METHODS: A total of 174 SPF patients in the Department of Orthopaedics, the First Affiliated Hospital of Chengdu Medical College from July 2015 to June 2018 were involved in this study and divided into EFR group (n = 87) and control group (n = 87) using the random number table method. Conventional fluid resuscitation (CFR) was performed in control group, and EFR was performed in EFR group. The incidences of acute respiratory distress syndrome (ARDS) and multiple organ dysfunction syndrome (MODS) during rescue, successful rescue rate, blood transfusion volume, fluid input, and resuscitation time were compared between the two groups. The parameters including prothrombin time (PT), hematocrit (HCT), platelet (PLT) and blood lactate (BL) at the 4th hour after fluid resuscitation were recorded. The levels of inflammatory factors (TNF-α, IL-6, CRP) and immune factors (CD3+, CD4+, CD8+, CD4+/CD8+) were compared between the two groups before treatment and 7 days after treatment. The revised acute physiologic and chronic health evaluation system and the sequential organ failure assessment scores were adopted for evaluation before treatment and 7 days after treatment. RESULTS: The incidences of ARDS and MODS during rescue in EFR group were significantly lower than those in control group (p=0.015 and 0.010 respectively), and the successful rescue rate in EFR group was significantly higher than that in control group (p = 0.011). The blood transfusion volume, fluid input, resuscitation time in EFR group were significantly lower than those in control group (p = 0.016, 0.002 and 0.001 respectively). At the 4th hour after fluid resuscitation, PT and BL in EFR group were significantly lower than those in control group (p = 0.021 and 0.003 respectively), while HCT and PLT in EFR group were significantly higher than those in control group (p = 0.016 and 0.021 respectively). On day 7 after treatment, TNF-α, IL-6, CRP and CD8+ in EFR group were significantly lower than those in control group (p = 0.003, 0.004, 0.007 and 0.003 respectively), while CD3+, CD4+ and CD4+/CD8+ in EFR group were significantly higher than those in control group (p = 0.004, 0.000, 0.007 respectively). On day 7 after treatment, the revised acute physiologic and chronic health evaluation (APACHE) system and the sequential organ failure assessment (SOFA) scores in EFR group were significantly lower than those in control group. CONCLUSION: EFR can effectively eliminate inflammatory factors, improve immune function, maintain the stability of blood components, reduce the incidences of ARDS and MODS, and elevate the successful rescue rate in patients with SPF.

Effects of Ulinastatin on In Vitro Storage Lesions of Human Red Blood Cells.

BACKGROUND: The study aimed to investigate the influence of in vitro storage on erythrocyte complement receptor one (E-CR1), cell shrinkage and eryptosis of human red blood cells (RBCs), and to assess the possible effects of ulinastatin (UTI) on them. METHODS: After collection, RBCs were treated with saline (control group) and different concentrations of UTI (5,000 U/mL, 10,000 U/mL, and 50,000 U/mL in Group C1, Group C2, and Group C3, respectively). E-CR1, cell size, and phosphatidylserine (PS) exposure and intracellular Ca2+ concentration were analyzed by flow cytometer every 7 days up to Day 35. RESULTS: E-CR1 level and cell size of all groups decreased during storage. In the control group, E-CR1 began to decrease on Day 28 and cells shrank on Day 21. The E-CR1 level of Group C2 was significantly higher than that of the control group beginning on Day 21. The cells of Group C1 and Group C2 began to shrink remarkably on Day 21, and those of Group C3 on Day 35. PS-exposure levels of 4 groups started to increase on Day 7 (p < 0.05), while from Day 14 to 35 those of Group C3 were significantly lower than the control group (p < 0.05). The intracellular Ca2+ levels of the control group started to increase significantly on Day 7, one week earlier than the experimental groups. From Day 21 to 35, the intracellular Ca2+ levels of Group C2 and C3 were significantly lower than those of the control group (p < 0.05). CONCLUSIONS: RBCs underwent E-CR1 loss, cell shrinkage, and eryptosis during in vitro storage, which could be attenuated by UTI.

[Research on output and quality of Panax notoginseng and annual change characteristics of N, P and K nutrients of planting soil under stereo-cultivation].

The output and agronomic characters of 3-year-old Panax notoginseng cultured under stereo structure (upper, middle and down layers) were investigated, and the annual change of N, P and K of its planting soil were also studied. Results showed that, compared with field cultured Panax notoginseng, growth vigour and output of stereo-cultivation were significantly lower. But the total production of the 3 layers was 1.6 times of field. The growth vigor and production of P. notoginseng was in the order of upper layer > middle layer > down layer. The content of ginsenoside in rhizome, root tuber and hair root of P. notoginseng was in the order of upper layer > field > middle layer > down layer. Organic matter content and pH of stereo-cultivation soil decreased with the prolonging of planting time, which with the same trend of yield. Organic matter content of stereo-cultivation soil was significantly higher than field, but the pH was significantly lower. Contents of total and available N, P and K in stereo-cultivation soil and field decreased with the prolonging of planting time. The content of N and P were in the order of upper layer > middle layer > yield > down layer, the content of K was in the order of upper layer > middle layer > down layer > yield. Compared with field, the proportion of N and P in the organ of underground (rhizome, root tuber and hair root) of upper layer were increased, while decreased in middle and down layers. Proportion of K in underground decreased significantly of the 3 layers. In conclusion, the agronomic characters and production of stereo-cultivation were significantly lower than that of yield. But the total production of the 3 layers were significantly higher than field of unit area. And the aim of improving land utilization efficiency was achieved. Nutritions in the soil of stereo-cultivation were enough to support the development of P. notoginseng, which was not the cause of weak growth and low production. The absorbing ability of P. notoginseng to N, P and K nutrients was decreased by stereo-cultivation mode. So, improve the growth vigour of P. notoginseng from the perspective of adjusting the stereo-cultivation mode so as to improve the nutrient absorption capacity is the future direction.

Acute macular neuroretinopathy following COVID-19 infection: Three case reports.

BACKGROUND: During the Coronavirus disease 2019 (COVID-19) pandemic, a notable increase in acute macular neuroretinopathy (AMN) cases was observed. This study aimed to investigate the potential association between AMN and COVID-19 by examining 3 cases in China. CASE SUMMARY: The first case involved a 30-year-old man who presented with progressive vision loss following a COVID-19 infection. Optical coherence tomography (OCT) and near-infrared imaging identified hallmark AMN lesions, hyperreflective disruptions within the outer plexiform layer, and hyporeflective anomalies in the ellipsoid zone, leading to an AMN diagnosis. Despite partial visual recovery, OCT angiography (OCTA) revealed persistent microvascular changes, specifically a decreased vascular density in the deep capillary plexus. The second case was a 24-year-old woman who experienced blurred vision and exhibited bilateral cotton-wool spots on fundus examination post-COVID-19. Imaging confirmed the presence of AMN along with paracentral acute middle maculopathy (PAMM). Follow-up OCTA found a progressive reduction in vascular density, indicating ongoing microvascular compromise. The third case was a 28-year-old woman who reported sensations of occlusion in her right eye following a COVID-19 infection. Imaging confirmed both AMN and PAMM, revealing similar decreases of microvascular density on OCTA despite a significant improvement in visual acuity. We noted that all 3 patients had received the COVID-19 vaccine prior to the appearance of symptoms. CONCLUSION: The findings highlight the diagnostic utility of advanced ocular imaging in detecting AMN in COVID-19 patients and the importance of comprehensive eye examinations.

Expression of cytokines in mouse hepatitis B virus X gene-transfected model.

The expression profile in the mouse hepatitis B virus X (HBx)-transfected model was investigated in order to lay a foundation for further study on the implication of cytokines expression in hepatitis B virus (HBV) infection. Hydrodynamic injection method via the tail vein was used to establish the animal HBx-transfected model. By using microassay, the differential expression of gene in each group was analyzed, which was further confirmed by using real-time PCR and semi-quantitative PCR. Most of chemokine genes such as Ccl2, Ccl5, Ccl9, MIG and IP-10 were up-regulated in the HBx-transfected mouse model versus the control mice, which was coincided with the microarray results. Western blotting and immunohistochemistry were applied to detect the expression of MIG and IP-10 in the liver tissues. Simultaneously, ELISA was adopted to measure the content of IFN-γ in the liver tissues. DNA microassay revealed that the expression of 611 genes changed in HBx-transfected mice as compared with that in pCMV-tag2B-transfected mice, and most of the screened chemokines were up-regulated (including MIG and IP-10). Additionally, IFN-γ protein levels were increased by 20.7% (P<0.05) in pCMV-tag2B-HBx-transfected mice as compared with the untreated mice. IFN-γ protein levels were reduced by 53.9% (P<0.05) in pCMV-tag2B-transfected mice as compared with the untreated mice, which was consistent with the up-regulation of MIG and IP-10. It was suggested HBx transfection could induce the expression of MIG and IP-10 in the liver tissues, which might play the roles in HBV-related liver immunity and cytokines-mediated antiviral effect.

Chemotherapy and radiotherapy downregulate the activity and expression of DNA methyltransferase and enhance Bcl-2/E1B-19-kDa interacting protein-3-induced apoptosis in human colorectal cancer cells.

Bcl-2/E1B 19-kDa interacting protein 3 (BNIP3) is a proapoptotic protein whose expression level is often low in colorectal cancer (CRC) cells due to the BNIP3 gene promoter DNA methylation by DNA methyltransferase (DNMT). It is known that chemotherapy and radiotherapy suppress CRC through inducing tumor apoptosis. However, the molecular mechanisms underlying chemotherapy and radiotherapy-induced apoptosis of CRC cells are not well defined. In this study, we observed that the expression level of BNIP3 in colon cancer cells was significantly increased by treatment with therapeutic agents and radiation in vitro. The BNIP3 protein level in CRC tissues from patients who received preoperative concurrent chemotherapy was significantly higher than in those who received surgery alone. Furthermore, treatment with chemotherapeutic agents and radiation significantly decreased the DNMT1 expression level and enzymatic activity. Both expression level and activity of DNMT1 were inversely correlated with the expression level of BNIP3 in colon carcinoma cells after treatment with chemotherapeutic agents and radiation. Consistent with increased BNIP3 expression, chemotherapeutic agents and radiation induced colon carcinoma cell apoptosis in a dose-dependent manner. Based on these observations, we conclude that chemotherapy and radiotherapy inhibit DNMT1 expression to upregulate BNIP3 expression to promote CRC cell apoptosis. And, BNIP3 may play a role in the caspase-dependent apoptosis pathways, mainly during treatment with chemotherapy and radiotherapy.

Can circulating interleukin-18 differentiate between sarcoidosis and idiopathic pulmonary fibrosis?

OBJECTIVE: The aim of the present study was to investigate serum and bronchoalveolar lavage fluid (BALF) interleukin-18 (IL-18) levels in sarcoidosis and idiopathic pulmonary fibrosis (IPF) and to assess the clinical usefulness of IL-18 in these diseases. METHODS: Serum and BALF levels of IL-18 were measured in 15 patients with sarcoidosis, 10 patients with IPF and 24 control subjects (8 with lung tumor, 6 with pulmonary tuberculosis and 10 healthy controls). Lymphocyte fractions (T, B and natural killer (NK) cells) in blood and BALF were analysed by flow cytometer. RESULTS: The serum and BALF levels of IL-18 in patients with sarcoidosis were significantly higher (p < 0.05) than those in IPF subjects and control groups. The percentages of T, B and NK cells in blood and BALF did not differ among all groups, while the blood and BALF CD4/CD8 ratios in patients with sarcoidosis were significantly higher (p < 0.05) than those in the other groups. Among all subjects, the serum levels of IL-18 correlated positively with the CD4/CD8 ratios in BALF (r = 0.693, p < 0.001). CONCLUSIONS: As to the levels of IL-18 in serum and BALF, there were differences between sarcoidosis and IPF indicating a different role of IL-18 in the pathogenesis of these diseases. Measurement of circulating IL-18 might have a potential of clinical utility in the differential diagnosis of sarcoidosis versus IPF.

Associations of Serum S100A12 With Severity and Prognosis in Patients With Community-Acquired Pneumonia: A Prospective Cohort Study.

Background: Previous studies indicated the calcium-binding protein S100A12 to be involved in the pathophysiology of pulmonary inflammatory diseases. However, the role of S100A12 has remained elusive in patients with community-acquired pneumonia (CAP). Therefore, the purpose of this prospective cohort study was to evaluate the association between serum S100A12 with severity and prognosis in CAP patients. Methods: Two groups with either 239 CAP patients or 239 healthy controls were enrolled in our study. Fasting blood and clinical characteristics were collected. On admission, serum S100A12 was measured using enzyme-linked immunosorbent assay (ELISA). Results: Serum S100A12 was increased in CAP patients compared to control subjects. Furthermore, serum S100A12 was elevated according to the severity of CAP. Correlative analysis suggested that the level of serum S100A12 was associated with blood routine indices, renal function markers, inflammatory cytokines and other clinical parameters among CAP patients. Additionally, linear and logistical regression analyses indicated that serum S100A12 was positively associated with CAP severity scores in CAP patients. In addition, the association of high serum S100A12 and prognosis was accessed using a follow-up research. Elevated serum S100A12 on admission increased the risk of death and hospital stay in CAP patients during hospitalization. Conclusions: Elevated serum S100A12 on admission is positively associated with the severity and adverse prognosis in CAP patients, suggesting that S100A12 may involve in the pathophysiological process of CAP. The titre of serum S100A12 may be used as a biomarker for diagnosis and prognosis among CAP patients.

Corrigendum: Associations of Serum S100A12 With Severity and Prognosis in Patients With Community-Acquired Pneumonia: A Prospective Cohort Study.

[This corrects the article DOI: 10.3389/fimmu.2021.714026.].

[Effect and mechanism of DNMT inhibitor on the reversal of multidrug resistance in human colon cancer cell line sw620/L-OHP].

OBJECTIVE: To explore whether demethylation inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) could reverse multidrug resistance (MDR) of human colon cancer and its impacts on the expressions of Bcl-2/adenovirus E1B 19 KDa protein interacting protein 3 (BNIP3), P-glycoprotein (P-GP) and multidrug resistance-associated protein (MRP), as well as the activity of DNA methyltransferase (DNMT). METHODS: Oxaliplatin (L-OHP) resistant human colon carcinoma cells (sw620/L-OHP) and its parental cells (sw620) were used to determine the effect of 5-aza-dC. CCK-8 assay was adopted to evaluate the cytotoxicity of 5-aza-dC. Western blot was performed to observe the expressions of BNIP3, P-GP and MRP. H microassay was used to detect the activity of DNMT. RESULTS: After the addition of 1.4 micromol/L 5-aza-dC, the 50% inhibitory concentration (IC50) of L-OHP to sw620/ L-OHP cells was decreased from (0.335 +/- 0.043) microg/mL to (0.069 +/- 0.023) microg/mL, and the chemosensitivity increased 8.26 times (P < 0.001). Western blot analysis showed that the expression of BNIP3 was up-regulated by 5-aza-dC in a concentration-dependent manner (P < 0.001), and P-GP and MRP expression were also significantly changed (P < 0.05) but not in a concentration-dependent manner (P > 0.05). DNMT activity was down-regulated by 5-aza-dC in sw620/L-OHP cells (P < 0.001). CONCLUSIONS: 5-aza-dC could reversed multi drug resistance of sw620/L-OHP, which may due to the demethylation to upregulate BNIP3 expression, and inhibit the expression of resistance-associated protein P-GP and MRP further by some unknown mechanism.

Immobilization of uranium into magnetite from aqueous solution by electrodepositing approach.

Immobilization of uranium into magnetite (Fe3O4), which was generated from metallic iron by electrochemical method, was proposed to rapidly remove uranium from aqueous solution. The effects of electrochemical parameters such as electrode materials, voltage, electrode gap, reaction time and pH value on the crystallization of Fe3O4 and uranium removal efficiencies were investigated. More than 90% uranium in the solution was precipitated with Fe3O4 under laboratory conditions when uranium concentration range from 0.5mg/L to 10mg/L. The Fe3O4 crystallization mechanism and immobilization of uranium was proved by XPS, XRD, TEM, FTIR and VSM methods. The results indicated that the cationic (including Fe2+, Fe3+ and U(VI)) migrate to cathode side under the electric field and the uranium was incorporated or adsorbed by Fe3O4 which was generated at cathode while the pH ranges between 2-7. The uranium-containing precipitate of Fe3O4 can exist stably at the acid concentration below 60g/L. Furthermore, the precipitate may be used as valuable resources for uranium or iron recycling, which resulted in no secondary pollution in the removal of uranium from aqueous solution.

Gastrodin inhibits high glucose­induced human retinal endothelial cell apoptosis by regulating the SIRT1/TLR4/NF­κBp65 signaling pathway.

Diabetic retinopathy (DR), one of the most common complications of late­phase diabetes, is associated with the ectopic apoptosis of microvascular cells. Gastrodin, a phenolic glucoside derived from Gastrodia elata Blume, has been reported to have antioxidant and anti­inflammation activities. The aim of the present study was to investigate the effects of gastrodin on high glucose (HG)­induced human retinal endothelial cell (HREC) injury and its underlying mechanism. The results demonstrated that HG induced cell apoptosis in HRECs, which was accompanied by increased levels of reactive oxygen species production. Gastrodin treatment significantly alleviated HG­induced apoptosis and oxidative stress. Furthermore, HG stimulation decreased the levels of SIRT1, which was accompanied by an increase in Toll­like receptor 4 (TLR4) expression and the levels of phosphorylated nuclear factor (NF)­κBp65. However, the administration of gastrodin significantly inhibited the activation of the sirtuin 1 (SIRT1)/TLR4/NF­κBp65 signaling pathway in HRECs exposed to HG. Collectively, the present study demonstrated that gastrodin may be effective against HG­induced apoptosis and its action may be exerted through the regulation of the SIRT1/TLR4/NF­κBp65 signaling pathway.

Inhibition of TLR4 protects rat islets against lipopolysaccharide-induced dysfunction.

Oxidative stress leads to dysfunction in pancreatic cells, causing a reduction in insulin secretion following exposure to glucose. Toll-like receptor 4 (TLR4) may be activated by exposure to lipopolysaccharide (LPS) stress. TLR4 may mediate the initiation of inflammatory and immune defense responses; however, the importance of the LPS/TLR4 interaction in apoptosis induced by oxidative stress in pancreatic ß cells remains to be elucidated. The present study aimed to investigate the importance of TLR4 during LPS­induced oxidative stress, apoptosis and dysfunction of insulin secretion in isolated islets of rats. LPS­induced stimulation of TLR4 increased the production of reactive oxygen species and promoted apoptosis by upregulating the expression levels of caspase­3, poly ADP ribose polymerase and altering the expression ratio of B­cell lymphoma­2 (Bcl­2)/Bcl­2 associated X protein. Additionally, the insulin secretion of islets cells was reduced. Anti­TLR4 antibody and a knockdown of TLR4 by TLR4­short hairpin RNA were used to inhibit TLR4 activity, which may reverse LPS­induced events. The present study determined that in islets exposed to LPS oxidative stress, dysfunction may be partly mediated via the TLR4 pathway. Inhibition of TLR4 may prevent dysfunction of rat islets due to oxidative stress. The present study revealed that targeting the LPS/TLR4 signaling pathway and antioxidant therapy may be a novel treatment for the severely septic patients with hyperglycemia stress.