MicroRNA-7 attenuates secondary brain injury following experimental intracerebral hemorrhage via inhibition of NLRP3.

BACKGROUND AND PURPOSE: The pathophysiological mechanisms underlying brain injury resulting from intracerebral hemorrhage (ICH) remain incompletely elucidated, and efficacious therapeutic interventions to enhance the prognosis of ICH patients are currently lacking. Previous research indicates that MicroRNA-7 (miR-7) can suppress the expression of Nod-like receptor protein 3 (NLRP3), thereby modulating neuroinflammation in Parkinson's disease pathogenesis. However, the potential regulatory effects miR-7 on NLRP3 inflammasome after ICH are yet to be established. This study aims to ascertain whether miR-7 mitigates secondary brain injury following experimental ICH by inhibiting NLRP3 and to investigate the underlying mechanisms. METHODS: An ICH model was established by stereotaxically injecting 100 µL of autologous blood into the right basal ganglia of Sprague-Dawley (SD) rats. Subsequently, these rats were allocated into three groups: sham, ICH + Vehicle, and ICH + miR-7, each comprising 18 animals. Twelve hours post-modeling, rats received intraventricular injections of 10 µL physiological saline, 10 µL phosphate, and 10 µL phosphate-buffered saline solution containing 0.5 nmol of miR-7 mimics, respectively. Neurological function was assessed on day three post-modeling, followed by euthanasia for brain tissue collection. Brain water content was determined using the dry-wet weight method. The expression of inflammatory cytokines in cerebral tissues surrounding the hematoma was analyzed through immunohistochemistry and Western blot assays. These cytokines were re-evaluated using Reverse Transcription-Polymerase Chain Reaction (RT-PCR). Moreover, bioinformatics tools were employed to predict miR-7's binding to NLRP3. A wild-type luciferase reporter gene vector and a corresponding mutant vector were constructed, followed by transfection of miR-7 mimics into HEK293T cells to assess luciferase activity. RESULTS: Our study demonstrates that the administration of miR-7 mimics markedly reduced neurological function scores and attenuated brain edema in rats following ICH. A significant upregulation of NLRP3 expression in microglia/macrophage adjacent to the hematoma was observed, substantially reduced after the treatment with miR-7 mimics. Furthermore, this intervention ameliorated neurodegenerative changes and effectively decreased the protein and mRNA levels of pro-inflammatory cytokines, namely TNF-α, IL-1ß, IL-6, and Caspase1, in the cerebral tissues proximate to the hematomas. In addition, miR-7 mimics distinctly inhibited the luciferase activity associated with the wild-type reporter gene, an effect not mirrored in its mutant variant. CONCLUSIONS: The miR-7 suppressed NLRP3 expression in microglia/macrophage to reduce the production of inflammatory cytokines, leading to conducting certain neuroprotection post-ICH in rats.

CircRNA 06209 inhibits cataract development by sponging miR-6848-5p and regulating ALOX15 expression.

Cataract is the leading cause of blindness in the world, and there is a lack of effective treatment drugs. CircRNA plays an important part in a variety of diseases, however, the role of circRNA in cataracts remains largely unknown. In this study, we constructed a cataract model of rats and obtained the circRNAs related to cataracts by whole transcriptome sequencing and circRNA-mRNA co-expression network. To investigate the effect and mechanism of circRNA 06209 on cataracts, we performed several in vivo and in vitro experiments, including CCK8 assay, flow cytometry, dual luciferase reporter assay, RIP assay, actinomycin D assay, and Western blot analysis. We identify that a necroptosis-related circRNA, circRNA 06209, is down-regulated in cataracts. Vitro experiments showed that up-regulation of circRNA 06209 could promote cell proliferation and inhibit cell apoptosis. Vivo experiments revealed that circRNA 06209 overexpression could inhibit the development of cataracts. Mechanistically, circRNA 06209 acts as a miRNA sponge and competitively binds to miR-6848-5p to curb the inhibitory effect of miR-6848-5p on ALOX15, thereby affecting cell viability and apoptosis. This study found that circRNA 06209 plays a critical part in inhibiting cataracts through the miR-6848-5p/ALOX15 pathway, suggesting that circRNA 06209 may be a promising therapeutic target for cataracts.

Transcriptome sequencing and microRNA-mRNA regulatory network construction in the lens from a Na2SeO3-induced Sprague Dawley rat cataract model.

BACKGROUND: A sight-threatening, cataract is a common degenerative disease of the ocular lens. This study aimed to explore the regulatory mechanism of age-related cataract (ARC) formation and progression. METHODS: Cataracts in Sprague Dawley rats were induced by adopting the method that injected selenite subcutaneously in the nape. We performed high-throughput RNA sequencing technology to identify the mRNA and microRNA(miRNA) expression profiles of the capsular membrane of the lens from Na2SeO3-induced and saline-injected Sprague Dawley rats. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were carried out to forecast the regulatory and functional role of mRNAs in cataracts by DAVID and Metascape. The protein-protein interaction(PPI) network of differentially expressed mRNA(DEmRNAs) was built via the STRING. Target miRNAs of hub genes were predicted by miRBD and TargetScan. Furthermore, differentially expressed miRNA(DEmiRNAs) were selected as hub genes' targets, validated by quantitative real-time polymerase chain reaction(qRT-PCR), and a DEmiRNA-DEmRNA regulatory network was constructed via Cytoscape. RESULT: In total, 329 DEmRNAs including 40 upregulated and 289 downregulated genes were identified. Forty seven DEmiRNAs including 29 upregulated and 18 downregulated miRNAs were detected. The DEmRNAs are involved in lens development, visual perception, and aging-related biological processes. A protein-protein interaction network including 274 node genes was constructed to explore the interactions of DEmRNAs. Furthermore, a DEmiRNA-DEmRNA regulatory network related to cataracts was constructed, including 8 hub DEmRNAs, and 8 key DEmiRNAs which were confirmed by qRT-PCR analysis. CONCLUSION: We identified several differentially expressed genes and established a miRNA-mRNA-regulated network in a Na2SeO3-induced Sprague Dawley rat cataract model. These results may provide novel insights into the clinical treatment of cataracts, and the hub DEmRNAs and key DEmiRNAs could be potential therapeutic targets for ARC.

Global, regional, national burden and gender disparity of cataract: findings from the global burden of disease study 2019.

BACKGROUND: To evaluate the global burden of cataracts by year, age, region, gender, and socioeconomic status using disability-adjusted life years (DALYs) and prevalence from the Global Burden of Disease (GBD) study 2019. METHODS: Global, regional, or national DALY numbers, crude DALY rates, and age-standardized DALY rates caused by cataracts, by year, age, and gender, were obtained from the Global Burden of Disease Study 2019. Socio-demographic Index (SDI) as a comprehensive indicator of the national or regional development status of GBD countries in 2019 was obtained from the GBD official website. Kruskal-Wallis test, linear regression, and Pearson correlation analysis were performed to explore the associations between the health burden with socioeconomic levels, Wilcoxon Signed-Rank Test was used to investigate the gender disparity. RESULTS: From 1990 to 2019, global DALY numbers caused by cataracts rose by 91.2%, crude rates increased by 32.2%, while age-standardized rates fell by 11.0%. Globally, age-standardized prevalence and DALYs rates of cataracts peaked in 2017 and 2000, with the prevalence rate of 1283.53 [95% uncertainty interval (UI) 1134.46-1442.93] and DALYs rate of 94.52 (95% UI 67.09-127.24) per 100,000 population, respectively. The burden was expected to decrease to 1232.33 (95% UI 942.33-1522.33) and 91.52 (95% UI 87.11-95.94) by 2050. Southeast Asia had the highest blindness rate caused by cataracts in terms of age-standardized DALY rates (99.87, 95% UI: 67.18-144.25) in 2019. Gender disparity has existed since 1990, with the female being more heavily impacted. This pattern remained with aging among different stages of vision impairments and varied through GBD super regions. Gender difference (females minus males) of age-standardized DALYs (equation: Y = -53.2*X + 50.0, P < 0.001) and prevalence rates (equation: Y = - 492.8*X + 521.6, P < 0.001) was negatively correlated with SDI in linear regression. CONCLUSION: The global health of cataracts is improving but the steady growth in crude DALY rates suggested that health progress does not mean fewer demands for cataracts. Globally, older age, females, and lower socioeconomic status are associated with higher cataract burden. The findings of this study highlight the importance to make gender-sensitive health policies to manage global vision loss caused by cataracts, especially in low SDI regions.

Effects of Chronic Restraint Stress on Apoptosis of Amygdala Cells in Rats.

OBJECTIVES: To explore the damage effects of chronic restraint stress (CRS) on amygdala cells through the rat CRS model. METHODS: The rat CRS model was established, and the changes in body weight and adrenal mass in control group and CRS group were monitored at 1 d, 7 d, 14 d and 21 d. The behavior changes were evaluated by the percentage of retention time of open arms and open arm entries using the elevated plus maze (EPM). ELISA was used to detect the concentrations of rat's corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and cortisol. The changes of expression of glucocorticoid receptor (GR) and glial fibrillary acidic protein (GFAP) in amygdala were determined by immunohistochemistry and Western blotting. Ultrastructure changes of glial cell were observed by transmission electron microscopy. The apoptosis rate of amygdala was measured by flow cytometry. RESULTS: Compared with the control group at the same time points, body weight of CRS 1 d, 7 d, 14 d and 21 d groups increased slowly, but adrenal mass increased significantly; the serum level of CRH, cortisol and ACTH increased significantly at 7 d, 14 d and 21 d respectively; the expression of GR in amygdala was increased while that of GFAP was decreased; EPM test suggested that the percentage of retention time of open arms and open arm entries decreased significantly after 14 d. The CRS group showed different degrees of glial cell damage in amygdala, and the apoptosis rate of glial cell was significantly increased in 21 d group. CONCLUSIONS: This study successfully established a CRS model in rats, and anxiety-like behavioral changes in model rats may be caused by apoptosis of amygdala astrocytes.

Molecular detection and genetic diversity of Rickettsia spp. in pet dogs and their infesting ticks in Harbin, northeastern China.

BACKGROUND: Pet dogs are important companion animals that share the environment within households, and play an important role in local community life. In addition, pet dogs also are reservoirs of zoonotic agents, including Rickettsia spp., thus increasing the risk of rickettsial infections in humans. It's meaningful to investigate the epidemiology of rickettsial agents in pet dogs, and make contribute to the surveillance of rickettsioses in human in China. RESULTS: In this study, a total of 496 pet dogs' blood samples and 343 ticks infested in pet dogs were collected, and the presence and prevalence of Rickettsia were determined by amplifying the partial gltA and 17-kDa genes, with an overall positive rate of 8.1 % in blood samples and 14.0 % in tick samples. In addition, the rrs, gltA, groEL, and ompA genes of rickettsial were also recovered to determine the species of Rickettsia detected furtherly. Sequencing blast and phylogenetic analyses revealed the presence of three human pathogenic Rickettsia species (Rickettsia raoultii, Candidatus Rickettsia tarasevichiae and Rickettsia felis) in samples associated with pet dogs. Moreover, all the sequences of Rickettsia that we obtained presented close relationship with others available in GenBank, and Rickettsia raoultii was the most predominant Rickettsia species infected in pet dogs' blood samples or in tick samples. CONCLUSIONS: This study provides the molecular epidemiology data about the Rickettsia spp. infection associated with pet dogs in urban areas of Harbin city. Three rickettisae species pathogenic to humans were identified from pet dogs' blood and the infested ticks in urban areas of Harbin city. Considering the intimate relationship between human and pets, these results indicate the potential transmission risk of human rickettisal infections from pet dogs through ectoparasites, and also highlighting that more attention should be paid to rickettsial infection in pet dogs and the infested ticks from the "One health" perspective.

Sulforaphane prevents rat cardiomyocytes from hypoxia/reoxygenation injury in vitro via activating SIRT1 and subsequently inhibiting ER stress.

AIM: Sulforaphane (SFN), a natural dietary isothiocyanate, is found to exert beneficial effects for cardiovascular diseases. This study aimed to investigate the mechanisms underlying the protective effects of SFN in a model of myocardial hypoxia/reoxygenation (H/R) injury in vitro. METHODS: Cultured neonatal rat cardiomyocytes pretreated with SFN were subjected to 3-h hypoxia followed by 3-h reoxygenation. Cell viability and apoptosis were detected. Caspase-3 activity and mitochondrial membrane potential (ΔΨm) was measured. The expression of ER stress-related apoptotic proteins were analyzed with Western blot analyses. Silent information regulator 1 (SIRT1) activity was determined with SIRT1 deacetylase fluorometric assay kit. RESULTS: SFN (0.1-5 µmol/L) dose-dependently improved the viability of cardiomyocytes, diminished apoptotic cells and suppressed caspase-3 activity. Meanwhile, SFN significantly alleviated the damage of ΔΨm and decreased the expression of ER stress-related apoptosis proteins (GRP78, CHOP and caspase-12), elevating the expression of SIRT1 and Bcl-2/Bax ratio in the cardiomyocytes. Co-treatment of the cardiomyocytes with the SIRT1-specific inhibitor Ex-527 (1 µmol/L) blocked the SFN-induced cardioprotective effects. CONCLUSION: SFN prevents cardiomyocytes from H/R injury in vitro most likely via activating SIRT1 pathway and subsequently inhibiting the ER stress-dependent apoptosis.

Experimental Study on the Characteristics of Chemiluminescence in Coal Water Slurry Diffusion Flames Based on Hot Oxygen Burner Technology.

Most published works focused on the characteristics of chemiluminescence in homogeneous flames, but the research about radiation spectrum in heterogeneous flames was still limited. In this paper, improved hot oxygen burner (HOB) technology is applied to ignite coal water slurry (CWS) directly in the open space, for stable combustion. Radiation spectrum and two-dimensional OH* chemiluminescence in methane and CWS diffusion flames are measured by a fiber optic spectrometer and a high-spatial-resolution UV imaging system. The results show that OH* (309.12 nm), CH* (431.42 nm) and C2* (463.52~563.43 nm) radicals exist in both methane and CWS diffusion flame, but Na* (589.45 nm), Li* (670.88 nm), K* (766.91, 770.06 nm), H* (816.04, 819.99 nm) radiation spectrum line and continuous black-body radiation have been detected only in the CWS flame. These differences can be used to characterize the combustion or gasification of CWS and distinguish whether CWS is ignited or not. In addition, the injection of CWS into methane flame leads to a significant reduction in OH* and an increase in C2* and CH* radiation intensity. This is because a lot of heat is absorbed in the processes of CWS combustion reactions. Then the generation of CH is inhibited, and the production of OH* is reduced. The increase of C2* and CH* is due to simple substance carbon produce more after injecting CWS. Besides, axial OH* radiation intensity increases at first then decreases, and the position of peak intensity is closer to outlet of hot oxygen burner compared with methane flames. Radial OH* radiation distribution is bimodal in methane flame because reactions take place in the thin layer where methane and oxygen meet. However, in CWS flame, radial OH* radiation distribution is always unimodal since CWS diffuses fiercely and mixes with oxygen sufficiently. As the ratio of oxygen atom to carbon atom ([O/C]e) increases, the reaction region of OH* radicals becomes larger in methane and CWS flame. This indicates that increasing oxygen can promote reactions and benefit OH* radicals' generation. Moreover, with the increase of CWS flow, reaction center is closer to burner outlet, OH* distribution range and peak intensity decrease obviously, CH*, C2*, Na*, Li*, K*, H* and black-body radiation intensities markedly rise. And these characteristics can reflect the changes of operation loads.

Inhibition of miR-29a-3p Alleviates Apoptosis of Lens Epithelial Cells via Upregulation of CAND1.

PURPOSE: Accumulated evidence has shown that microRNAs (miRNAs) are closely related to the pathogenesis and progression of senile cataracts. Here we investigate the effect of miR-29a-3p in cataractogenesis and determined the potential molecular mechanism involved. METHODS: In this study, we constructed a selenite cataract model in rats and obtained the miRNAs related to cataracts by whole transcriptome sequencing. To investigate the effect and mechanism of miR-29a-3p on cataracts, we performed several in vivo and in vitro experiments, including CCK8 assay, flow cytometry, luciferase reporter assay, Edu assay, and western blot analysis. RESULT: Sequencing data showed downregulation of miR-29a-3p in rats with selenite cataracts. Down-regulation of miR-29a-3p could promote lens epithelial cells (SRA01/04) proliferation and inhibit cell apoptosis, and miR-29a-3p silence could inhibit the development of cataracts. Additionally, CAND1 was a direct target gene for miR-29a-3p. CONCLUSION: These data demonstrate that miR-29a-3p inhibits apoptosis of lens epithelial cells by regulating CAND1, which may be a potential target for senile cataracts.

The burden of vision loss due to cataract in China: findings from the Global Burden of Disease Study 2019.

OBJECTIVE: To provide a reference for future policy and measure formulation by conducting a detailed analysis of the burden of vision loss due to cataract by year, age, and gender in China from 1990 to 2019. METHODS: Data on the prevalence and disability-adjusted life-years (DALYs) due to cataract in China and neighboring and other G20 countries were extracted from the 2019 Global Burden of Disease (GBD) study to observe the changing trends of vision loss. RESULTS: The number and rate of all-age prevalence and DALYs for cataract in China increased significantly from 1990 to 2019. The age-standardized DALYs rate witnessed a slowly declining trend by 10.16%. And the age-standardized prevalence increased by 14.35% over the 30-year period. Higher prevalence and DALYs were observed in female population from 1990 through 2019, with little improvement over the decades(all p < 0.001). The disease burden of cataract is higher in middle-aged and elderly people. Blindness accounted for the largest proportion of vision impairment burden caused by cataract in China. The age-standardized prevalence and DALY rate of cataract in China were lower than those in India and Pakistan, but higher than those in Russia, South Korea, North Korea, Singapore, and Japan. CONCLUSIONS: In the past 30 years, although the age-standardized DALYs rate has decreased slightly in China, the all-age prevalence and DALYs have both increased. This study highlights the importance of reducing cataract burden by providing timely and easily accessible quality care, especially in females and the elderly population.

Suppression of rat Frizzled-2 attenuates hypoxia/reoxygenation-induced Ca2+ accumulation in rat H9c2 cells.

Growing evidence suggests that Ca(2+) overload is one of the major contributors of myocardial ischemia/reperfusion-induced injury. Since Frizzled-2 receptor, a seven transmembrane protein, transduces downstream signaling by specialized binding of Wnt5a to increase intracellular Ca(2+) release, this work aimed to investigate the effect of Frizzled-2 on Ca(2+) accumulation in H9c2 cells, which were subjected to hypoxia/reoxygenation to mimic myocardial ischemia/reperfusion. After exposing H9c2 cells to hypoxia/reoxygenation, we observed higher expression of Frizzled-2 and Wnt5a as compared to control group cells. Hypoxia/reoxygenation-induced intracellular Ca(2+) accumulation approached that of cells transfected with frizzled-2 plasmid. In cells treated with RNAi specifically designed against frizzled-2, intracellular Ca(2+) in both hypoxia/reoxygenation-treated cells and plasmid-treated cells were decreased. Rats that underwent ischemia/reperfusion injury exhibited increased intracellular Ca(2+) with high expression levels of Frizzled-2 and Wnt5a as compared to the sham group. Our data indicates that upon binding to Wnt5a, increased Frizzled-2 expression after hypoxia/reoxygenation treatment activated intracellular calcium release in H9c2 cells. Our findings provide a new perspective in understanding calcium overload in myocardial ischemia/reperfusion.

Timing of Tracheostomy in Patients with Intracerebral Haemorrhage: A Propensity-Matched Analysis.

AIMS: Although early tracheostomy (ET) is recommended for patients with severe stroke, the optimal timing of tracheostomy for patients with intracerebral haemorrhage (ICH) remains controversial. This study aimed to explore the clinical characteristics, risk factors and timing of tracheostomy in patients after tracheal intubation using a propensity-matched analysis. METHODS: We conducted a retrospective database search and assessed 267 consecutive patients who underwent endotracheal intubation (175 of whom underwent tracheostomy) and ICH between July 2017 and June 2021. A logistic regression model was applied to identify the critical factors influencing the decision for tracheostomy by comparing factors in a tracheostomy group and a nontracheostomy group. Patients were divided into an early (≤5 days) or a late (>5 days) group according to the median time of tracheostomy. Propensity score matching was performed to adjust for possible confounders and investigate differences in outcomes between ET and late tracheostomy (LT). RESULTS: Among the 267 enrolled patients with ICH and endotracheal intubation, 65.5% received tracheostomy during hospitalisation, and 52.6% received ET. The independent risk factors for tracheostomy included National Institute of Health Stroke Scale (NIHSS) (odds ratio [OR]: 1.179; 95% confidence interval [CI]: 1.028-1.351; P = 0.018), aspiration (OR: 2.171; 95% CI: 1.054-4.471; P = 0.035) and infiltrates (OR: 2.149; 95% CI: 1.088-4.242; P = 0.028). Using propensity matching, we found that ET was associated with fewer antibiotic-using days (15 vs. 18; P < 0.001) and sedativeusing days (6 vs. 8; P < 0.001), shorter intensive care unit (ICU) Length of Study (LOS) (9 vs. 12; P < 0.05) and reduced in-ICU costs (3.59 vs. 7.4; P < 0.001) and total hospital costs (8.26 vs. 11.28, respectively; P < 0.001). Muscle relaxants (31.8% vs. 60.6%) were used less frequently in patients with ET (P = 0.001). However, there were no differences between the ET and LT groups in terms of modified Rankin Scale (mRS) (4 vs. 4; P = 0.932), in-general-ward costs (4.74 vs. 4.37; P = 0.052), mechanical ventilation days (6 vs. 6; P = 0.961) and hospital LOS (23 vs. 23; P = 0.735) as well as the incidences of ventilator-associated pneumonia (28.8% vs. 37.9%; P = 0.268), tracheostomyrelated complications (16.7% vs. 19.7%; P = 0.652), respiratory failure (24.2% vs. 31.8%; P = 0.333), all-cause deaths (15.2% vs. 16.7%; P = 0.812) and pneumonia (77.3% vs. 87.9%; P = 0.108). CONCLUSION: We recommend ET for high-risk patients with ICH. Although ET cannot reduce inhospital mortality or improve patient prognosis, it may help reduce hospital costs and ICU LOS as well as the use of antibiotics, sedatives and muscle relaxants.

Changes in tumor suppressors and inflammatory responses during hydrogen peroxide-induced senescence in rat fibroblasts.

Cell proliferation and senescence are processes induced by oxidative stress. In this study, we aimed to establish a cellular model of rapid proliferation and senescence of rat tail-tip fibroblasts by hydrogen peroxide (H2O2), a well-known oxidant. On this basis, changes in oxidative stress, inflammatory response and cell cycle of fibroblasts were studied. After H2O2 treatment, cell counting and flow cytometry results showed that 50 µM of H2O2 for 12 h and 100 µM for 8 h effectively promoted fibroblast proliferation, while 500 µM rapidly led to cell cycle arrest. In addition, stimulation with H2O2 at a concentration of 50 µM also promoted the inflammatory effects of the cells. At a concentration of 100 µM H2O2, the cellular antioxidant system began to collapse at 8 h and began to affect cellular activity. 500 µM of H2O2 at 4 h the levels of senescence-associated ß-galactosidase, a marker of senescence and oxidative stress, were almost positive in fibroblasts. In addition, we found that the risk of fibroblasts carcinogenesis increased with increased H2O2 stimulation. The results of this study indicate that H2O2 can cause rapid proliferation and senescence of fibroblasts and that its mechanism of action may be mainly through influencing cellular antioxidant systems, cellular inflammatory responses and cell cycle.

Comparison of the accuracy of intraocular lens power calculation formulas for eyes after corneal refractive surgery.

BACKGROUND: In cataract surgery, calculating intraocular lens (IOL) power in patients who have previously received corneal refractive surgery on the same eye presents a clinical challenge. This study aims to compare the accuracy of the Haigis-L, Barrett True-K, and Shammas-PL formulas in predicting the IOL power in eyes following corneal refractive surgery. METHODS: This study analyzed 32 eyes belonging to 28 patients who underwent cataract surgery and IOL implantation after previously undergoing myopic corneal refractive surgery. The IOL power was calculated using the Haigis-L, Barrett True-K, and Shammas-PL formulas, and the accuracy of the three formulas was compared. RESULTS: The Haigis-L, Barrett True-K, and Shammas-PL formulas had a mean arithmetic IOL prediction error of -0.65, -0.39, and -0.46, respectively. The mean numerical errors of the three formulas were significantly different from zero (P<0.001). The smallest median absolute refraction prediction error (median =0.40) belonged to the Barrett True-K formula, which was significantly smaller than that of the Haigis-L formula (median =0.57, P<0.05) but similar to that of the Shammas-PL formula (median =0.49, P>0.05). There was no significant difference in the percentage of eyes within either ±0.50 D or ±1.00 D of the predicted refraction error across the three formulas. CONCLUSIONS: The Barrett True-K formula can predict IOL power in eyes that have previously undergone myopic corneal refractive surgery better than the Haigis-L formula.

Spermidine-enhanced autophagic flux improves cardiac dysfunction following myocardial infarction by targeting the AMPK/mTOR signalling pathway.

BACKGROUND AND PURPOSE: Spermidine, a natural polyamine, is abundant in mammalian cells and is involved in cell growth, proliferation, and regeneration. Recently, oral spermidine supplements were cardioprotective in age-related cardiac dysfunction, through enhancing autophagic flux. However, the effect of spermidine on myocardial injury and cardiac dysfunction following myocardial infarction (MI) remains unknown. EXPERIMENTAL APPROACH: We determined the effects of spermidine in a model of MI, Sprague-Dawley rats with permanent ligation of the left anterior descending artery, and in cultured neonatal rat cardiomyocytes (NRCs) exposed to angiotensin II (Ang II). Cardiac function in vivo was assessed with echocardiography. In vivo and in vitro studies used histological and immunohistochemical techniques, along with western blots. KEY RESULTS: Spermidine improved cardiomyocyte viability and decreased cell necrosis in NRCs treated with angiotensin II. In rats post-MI, spermidine reduced infarct size, improved cardiac function, and attenuated myocardial hypertrophy. Spermidine also suppressed the oxidative damage and inflammatory cytokines induced by MI. Moreover, spermidine enhanced autophagic flux and decreased apoptosis both in vitro and in vivo. The protective effects of spermidine on cardiomyocyte apoptosis and cardiac dysfunction were abolished by the autophagy inhibitor chloroquine, indicating that spermidine exerted cardioprotective effects at least partly through promoting autophagic flux, by activating the AMPK/mTOR signalling pathway. CONCLUSIONS AND IMPLICATIONS: Our findings suggest that spermidine improved MI-induced cardiac dysfunction by promoting AMPK/mTOR-mediated autophagic flux.

Interleukin-1ß inhibits collagen synthesis and promotes its decomposition in cultured cardiac fibroblasts.

The present study aimed to investigate the effects of interleukin-1ß (IL-1ß) at different doses on collagen synthesis and decomposition in cultured cardiac fibroblasts from neonatal Sprague-Dawley rat. Cardiac fibroblasts were treated with IL-1ß (0.01, 0.1, 1, 10, 100 ng/mL) for 24 h. Cell DNA synthesis was measured by (3)H-thymidine ((3)H-TdR) incorporation and collagen synthesis was measured by (3)H-proline ((3)H-Pro) incorporation. Matrix metalloproteinase (MMP) activity was measured by gelatinase zymography. MMP-2, MMP-9 protein expressions were measured by Western blot. mRNA expressions of MMP-2 and MMP-9 were detected by reverse transcription-polymerase chain reaction (RT-PCR). Compared with that in the control group, the incorporation of (3)H-TdR and (3)H-Pro decreased in high-dose IL-1ß groups (≥0.1 ng/mL) but not in low-dose IL-1ß group (0.01 ng/mL). IL-1ß significantly increased MMP-2 and MMP-9 activities. IL-1ß (0.01-100 ng/mL) also dose-dependently increased the protein and mRNA expressions of MMP-2 and MMP-9 (P<0.05, P<0.01), respectively. These results suggest that IL-1ß decreases collagen synthesis and MMP activities through transcriptional and posttranslational processes via degrading collagen in a dose-dependent way. Elevation of IL-1ß is possibly involved in the process of ventricular remodeling after myocardial infarction, and the concentration of IL-1ß is possibly a major factor which affects the extent of ventricular remodeling.

[Screening for cellular signal transduction pathway involved in C-reactive protein induced endothelial cell inflammation].

OBJECTIVE: To investigate the cellular signal transduction pathway involved in participation of C-reactive protein (CRP) in inflammation process in endothelial cell. METHODS: Human umbilical vascular endothelial cells were cultured and characterized by anti-Factor VIII-related antigen. The cells were divided into CRP group and control group, and they were respectively treated with CRP (20 mg/L) or serum-free medium for 24 hours. RNAs of two groups were extracted and analyzed by human signal transduction pathway gene array. RESULTS: Expressions of 13 genes were increased, whereas expressions of 25 genes were decreased in CRP group compared with control group. Especially, WNT1 inducible signaling pathway protein 2 (WISP2) was increased by 37.63 folds, which was believed to involve in inflammation process as a growth factor, p53 was increased by 30.50 folds, which was a key factor to modulate apoptosis, whereas, Bcl-x and Bcl-2 were decreased by 9.61% and 49.95% which were characterized as an important factor to prevent apoptosis. Vascular cell adhesion molecule-1 (VCAM-1) was increased by 2.75 folds after treated with CRP, while intercellular adhesion molecular (ICAM) between two groups didn't show statistically significant difference. CONCLUSION: CRP may be involved in inflammatory process of endothelial cell, and the mechanism may be to induce apoptosis and activate cellular signal transduction pathway of cell adhesion proteins.

[Isolation and identification of pronuciferine monomer].

OBJECTIVE: To isolate and identify pronuciferine monomer. METHODS: The primary compositions in the seed of Nelumbo nucifera were extracted by supercritical CO2 way, then isolated and purified by column chroatography fractionation and identified by HPLC, TLC, GC-MS. RESULTS: A monomer was further isolated and purifed by column chromatography fractionation from the primary compositions in the seed of Nelumbo nucifera which were extracted by supercritical CO2 way. The compositions of the monomer was pronuciferine which wrer identified by HPLC, TLC, GC-MS. CONCLUSION: The pronucierine monomer could be isolated from the seed of Nelumbo nucifera by combining supercitical CO2 way with column chromatography fractionation, which will be available for further functional study.

[Role of AcSDKP on collagen synthesis and degradation in cultured rat cardiac fibroblast].

OBJECTIVE: To investigate the role of AcSDKP on collagen synthesis and degradation in cultured rat cardiac fibroblasts. METHODS: Neonatal rat cardiac fibroblasts were isolated and stimulated by PDGF. The cell proliferation was observed by (3)H-TdR incorporation assay. The synthesis of collagen was measured by (3)H-proline incorporation assay. The expression of type I and type III collagen and MMP-1 protein were measured by Western blot. The MMP-2 and MMP-9 activity was evaluated with zymography assay. RESULTS: PDGF stimulated cardiac fibroblasts proliferation with increased collagen synthesis and type I and type III collagen protein expressions as well as MMP-2 and MMP-9 activities and MMP-1 expression. AcSDKP inhibited cardiac fibroblasts proliferation induced by PDGF and reduced collagen synthesis and type I and type III collagen protein expression. AcSDKP also further up-regulated MMP-2 and MMP-9 activities and MMP-1 expression in cardiac fibroblasts induced by PDGF. CONCLUSION: AcSDKP inhibited proliferation and collagen synthesis and up-regulated matrix metalloproteinases activity or expression induced by PDGF, which was possibly related with the effect of AcSDKP anti-fibrosis.