Quality Changes in Black Chokeberry Juice Treated by Thermal-Assisted High Hydrostatic Pressure during Cold Storage.

The effects of thermal-assisted high hydrostatic pressure (TAHHP), high hydrostatic pressure (HHP), and thermal pasteurization (TP) treatments on the quality of aronia juice were evaluated in this study. The results showed that TAHHP and HHP significantly decreased the aerobic plate counts of aronia juice. No significant differences in terms of physicochemical properties, such as pH and total soluble solids, were observed between aronia juice treated with high pressure or thermal pasteurization treatment after 28 days of storage. TAHHP and HHP affected the colour and antioxidant characteristics of aronia juice, though to a significantly lower extent than TP. This result demonstrates that TAHHP and HHP can better maintain the original quality of aronia juice than TP. In summary, both TAHHP and HHP can maintain the microbiological safety and original quality characteristics of aronia juice. TAHHP can effectively increase the safety and duration of cold storage of aronia juice, and hence is highly useful for the juice industry.

Control of ice crystal nucleation and growth during the food freezing process.

Freezing can maintain a low-temperature environment inside food, reducing water activity and preventing microorganism growth. However, when ice crystals are large, present in high amounts, and/or irregularly distributed, irreversible damage to food can occur. Therefore, ice growth is a vital parameter that needs to be controlled during frozen food processing and storage. In this review, ice growth theory and control are described. Macroscopic heat and mass transfer processes, the relationship between the growth of ice crystals and macroscopic heat transfer factors, and nucleation theory are reviewed based on the reported theoretical and experimental approaches. The issues addressed include how heat transfer occurs inside samples, variations in thermal properties with temperature, boundary conditions, and the functional relationship between ice crystal growth and freezing parameters. Quick freezing (e.g., cryogenic freezing) and unavoidable temperature fluctuations (e.g., multiple freeze-thaw cycles) are both taken into consideration. The approaches for controlling ice crystal growth based on the ice morphology and content are discussed. The characteristics and initial mechanisms of ice growth inhibitors (e.g., antifreeze proteins (AFPs), polysaccharides, and phenols) and ice nucleation agents (INAs) are complex, especially when considering their molecular structures, the ice-binding interface, and the dose. Although the market share for nonthermal processing technology is low, there will be more work on freezing technologies and their theoretical basis. Superchilling technology (partial freezing) is also mentioned here.

Estimating the structure of sarcoplasmic proteins extracted from pork tenderloin thawed by a high-voltage electrostatic field.

The application of high-voltage electrostatic field (HVEF) is a novel method of thawing. To determine if HVEF thawing could lead to sarcoplasmic proteins denaturation, and to provide a theoretical estimation of the structure of the sarcoplasmic proteins, pork tenderloin was thawed by traditional and HVEF methods. The results from protein solubility analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimeter showed that HVEF thawing did not result in more protein denaturation than those thawed under air or running water. From the principal component analysis of FTIR raw spectra (1700-1600 cm-1, Amide I region), we observed some separations of samples with different thawing treatments. It was found that the proportions of α-helix (1650-1640 cm-1 spectral bands in the original data) could lead to the differences on the PC2 axis of score plots.

Physiological and biochemical changes during fruit maturation and ripening in highbush blueberry (Vaccinium corymbosum L.).

The sweetness of blueberry fruit increases over time, as acids are converted to sugars, and full flavor development is formed by harvest. We comprehensively analyzed the changes and correlation in physiological and biochemical characteristics of blueberries at different maturity stages, including texture, quality, taste and energy change. Our analysis revealed that total anthocyanin content increased and firmness decreased as fruit ripened. Percent moisture, titratable acid (TA), chlorophyll and carotenoid content also decreased, while total soluble solids (TSS), pH, TSS/TA ratio, vitamin C, soluble proteins, and ethylene production all increased. Antioxidant enzyme activity gradually increased during ripening but energy-related metabolites decreased. The flavor attributes of sweetness, bitterness, and sourness were readily perceived using an electronic tongue and a total of 76 volatile compounds were detected by GC-MS. In summary, the maturation of blueberries was correlated with increases of anthocyanins, nutrients, antioxidant activity, taste and aroma, but negatively correlated with energy metabolism.

Pericentric inversion of chromosome 6 and male fertility problems.

As a significant chromosomal structural abnormality, chromosomal inversion is closely related to male infertility. For inversion carriers, the interchromosomal effect explains male infertility, but its specific mechanism remains unclear. Additionally, inversion carriers with different chromosomes have different clinical manifestations. Therefore, genetic counseling is difficult in clinical practice. Herein, four male carriers of pericentric inversion in chromosome 6 have been described. Two patients showed asthenospermia, one showed azoospermia, and the wife of the remaining patient had recurrent miscarriages. Through a literature search, the association between the breakpoint of pericentric inversion in chromosome 6 and male fertility problems are also discussed in this study. Overall, important genes related to asthenospermia in chromosome 6p21 were found, which may be related to the clinical phenotype. These results suggest that physicians should focus on the breakpoints of inversion in genetic counseling.

Inhibitory effects of polyphenols from black chokeberry on advanced glycation end-products (AGEs) formation.

Plant-based polyphenols are known to exert mitigating effects on the harmful consequences of advanced glycation. In this study, the antioxidant and antiglycation properties of purified black chokeberry polyphenol and its dominant monomers were studied. The phenolics of black chokeberry had a significant inhibitory effect on glycation products at all stages. The highest inhibition of fructosamine (72.27%) was achieved by chlorogenic acid (CA). Epigallocatechin gallate (EGCG) showed an 84.47% inhibition of α-dicarbonyl and 54.44% inhibition of AGEs (advanced glycation end-products). However, the inhibition of α-dicarbonyl was impacted by the presence of Cu2+. In addition, an EGCG-induced increase in the protein α-helical structure to 21.43% was observed. Overall, EGCG was the main component inhibited protein glycosylation in the simulated glycation system. Furthermore, the mechanism of inhibition was a combination of scavenging free radicals, capturing metal ions, and alleviating changes in the secondary structure of proteins.

Total Talar Replacement With Custom-Made Vitallium Prosthesis for Talar Avascular Necrosis.

Background: The current study investigated the application of three-dimensional (3D) printing technology in the treatment of talar avascular necrosis (TAN). Custom-made Vitallium talar prostheses were designed and generated via 3D printing. We hypothesized that these talar prostheses would facilitate more stable positioning, better ergonomically fit the ankle joint surfaces, and promote favorable long-term prognoses. Material and Methods: Computed tomography scans of both ankle joints were acquired from three patients diagnosed with TAN. The talar on the unaffected side was used as the design blueprint. Hence, with the aid of 3D printing technology a customized talar prosthesis made from a novel Vitallium alloy could be manufactured for each individual patient. Results: In all three cases there were no signs of prosthesis loosening or substantial degenerative change in the surrounding area of the joint, but small osteophytes were observed on the tibial side and navicular side. No chronic infection or other prosthesis-related complications were observed in any of the patients. All three were able to walk without pain at the most recent follow-up. Conclusion: With the aid of 3D printing and a novel Vitallium alloy, total talar replacement achieved encouraging results in 3/3 patients. All patients were satisfied with their joint function, and were able to return to their daily activities without limitations. Although more cases and longer-term follow-up periods are required, the success rate reported herein is encouraging.

Melatonin restores osteoporosis-impaired osteogenic potential of bone marrow mesenchymal stem cells and alleviates bone loss through the HGF/PTEN/Wnt/ß-catenin axis.

BACKGROUND: Previous studies reported that melatonin exerts its effect on mesenchymal stem cell (MSC) survival and differentiation into osteogenic and adipogenic lineage. In the current study we aimed to explore the effect of melatonin on osteoporosis and relevant mechanisms. METHODS: Real-time qualitative polymerase chain reaction (RT-qPCR) and Western blot analysis were conducted to determine expression of HGF, PTEN, and osteoblast differentiation-related genes in ovariectomy (OVX)-induced osteoporosis mice and the isolated bone marrow MSCs (BMSCs). Pre-conditioning with melatonin (1 µmol/l, 10 µmol/l and 100 µmol/l) was carried out in OVX mice BMSCs. Bone microstructure was analyzed using micro-computed tomography and the contents of alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase 5b (TRAP5b) were detected by enzyme-linked immunosorbent assay in serum. BMSC proliferation was measured by cell-counting kit (CCK)-8 assay. Alizarin red S (ARS) staining and ALP activity assay were performed to assess BMSC mineralization and calcification. The activity of the Wnt/ß-catenin pathway was evaluated by dual-luciferase reporter assay. RESULTS: Melatonin prevented bone loss in OVX mice. Melatonin increased ALP expression and reduced TRAP5b expression. HGF and ß-catenin were downregulated, while PTEN was upregulated in the femur of OVX mice. Melatonin elevated HGF expression and then stimulated BMSC proliferation and osteogenic differentiation. Additionally, HGF diminished the expression of PTEN, resulting in activated Wnt/ß-catenin pathway both in vitro and in vivo. Furthermore, melatonin was shown to ameliorate osteoporosis in OVX mice via the HGF/PTEN/Wnt/ß-catenin axis. CONCLUSION: Melatonin could potentially enhance osteogenic differentiation of BMSCs and retard bone loss through the HGF/PTEN/Wnt/ß-catenin axis.

Screening of gene markers related to the prognosis of metastatic skin cutaneous melanoma based on Logit regression and survival analysis.

BACKGROUND: Bioinformatics was used to analyze the skin cutaneous melanoma (SKCM) gene expression profile to provide a theoretical basis for further studying the mechanism underlying metastatic SKCM and the clinical prognosis. METHODS: We downloaded the gene expression profiles of 358 metastatic and 102 primary (nonmetastatic) CM samples from The Cancer Genome Atlas (TCGA) database as a training dataset and the GSE65904 dataset from the National Center for Biotechnology Information database as a validation dataset. Differentially expressed genes (DEGs) were screened using the limma package of R3.4.1, and prognosis-related feature DEGs were screened using Logit regression (LR) and survival analyses. We also used the STRING online database, Cytoscape software, and Database for Annotation, Visualization and Integrated Discovery software for protein-protein interaction network, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses based on the screened DEGs. RESULTS: Of the 876 DEGs selected, 11 (ZNF750, NLRP6, TGM3, KRTDAP, CAMSAP3, KRT6C, CALML5, SPRR2E, CD3G, RTP5, and FAM83C) were screened using LR analysis. The survival prognosis of nonmetastatic group was better compared to the metastatic group between the TCGA training and validation datasets. The 11 DEGs were involved in 9 KEGG signaling pathways, and of these 11 DEGs, CALML5 was a feature DEG involved in the melanogenesis pathway, 12 targets of which were collected. CONCLUSION: The feature DEGs screened, such as CALML5, are related to the prognosis of metastatic CM according to LR. Our results provide new ideas for exploring the molecular mechanism underlying CM metastasis and finding new diagnostic prognostic markers.

Mussel-Inspired Gold Nanoparticle and PLGA/L-Lysine-g-Graphene Oxide Composite Scaffolds for Bone Defect Repair.

PURPOSE: Insufficient biological activity heavily restricts the application and development of biodegradable bone implants. Functional modification of bone implants is critical to improve osseointegration and bone regeneration. METHODS: In this study, L-lysine functionalized graphene oxide (Lys-g-GO) nanoparticles and polydopamine-assisted gold nanoparticle (AuNPs-PDA) coatings were applied to improve the biological function of PLGA scaffold materials. The effects of Lys-g-GO nanoparticles and AuNPs-PDA functionalized coatings on the physicochemical properties of PLGA scaffolds were detected with scanning electron microscopy (SEM), contact angle measurement, and mechanical testing instruments. In vitro, the effects of composite scaffolds on MC3T3-E1 cell proliferation, adhesion, and osteogenic differentiation were studied. Finally, a radial defect model was used to assess the effect of composite scaffolds on bone defect healing. RESULTS: The prepared AuNPs-PDA@PLGA/Lys-g-GO composite scaffolds exhibited excellent mechanical strength, hydrophilicity and antibacterial properties. In vitro, this composite scaffold can significantly improve osteoblast adhesion, proliferation, osteogenic differentiation, calcium deposition, and other cell behaviour. In vivo, this composite scaffold can significantly promote the new bone formation and collagen deposition in the radial defect site and presented good biocompatibility. CONCLUSION: The combination of bioactive nanoparticles and surface coatings shows considerable potential to enhance the osseointegration of bone implants.

Exploring the biochemical properties of three polyphenol oxidases from blueberry (Vaccinium corymbosum L.).

Purification of blueberry polyphenol oxidase (PPO) has not been substantially progressed for a long time, which leads to little further study. We purified three PPOs from blueberries for the first time by modified Native-Page. The PPO-2 consists of two subunits (68 and 36 kDa), whereas PPO-3 and PPO-4 contain only one subunit (36 kDa). The optimum pH and temperature of PPO-2, PPO-3, and PPO-4 were 5.8-6.2 and 40 °C-45 °C with catechol as a substrate. The optimal substrates for them were all catechol (Km = 14.91, 7.19, and 11.20, respectively). High-pressure processing (HPP) had a limited inhibitory effect on the three PPOs. The activities of PPO-2, PPO-3, and PPO-4 were significantly reduced with increased SDS concentration. The binding of substrate to catalytic cavity is related to the residues His76, His209, His213, Gly228, and Phe230. The carbonyl group of residue Gly228 is one of the key sites for screening substrates.

Bone Marrow Mesenchymal Stem Cell-Derived Exosomal miR-25 Regulates the Ubiquitination and Degradation of Runx2 by SMURF1 to Promote Fracture Healing in Mice.

Recent evidence has demonstrated that mesenchymal stem cells (MSCs) can release a large number of functionally specific microRNA (miRNA) microvesicles that play a role in promoting osteogenic differentiation, but the specific mechanism is not yet clear. Under such context, this study aims to elucidate the mechanism of bone marrow mesenchymal stem cell-derived exosomes (BMSC-Exo) promoting fracture healing in mice. We isolated and identified the BMSC-Exo. Bioinformatics analysis predicted high expression of miRNA in exosomes and verified the transfer of miR-25 in exosomes by immunofluorescence. Targeting relationship between miR-25 and Smad ubiquitination regulatory factor-1 (SMURF1) was predicted and verified by dual-luciferase reporter gene assay. Immunoprecipitation and protein stability assays were used to detect Runt-related transcription factor 2 (Runx2) ubiquitination and the effect of SMURF1 on Runx2 ubiquitination, respectively. The effect of miR-25 in BMSC-Exo on fracture healing in mice was assessed using X-ray imaging. alkaline phosphatase, alizarin red staining, EdU, CCK-8, and Transwell were used to evaluate the effects of exosomes transferred miR-25 on osteogenic differentiation, proliferation, and migration of osteoblasts. Bioinformatics analysis predicted that miR-25 expression in exosomes increased significantly. Moreover, the targeted regulation of SMURF1 by miR-25 was verified. SMURF1 inhibited Runx2 protein expression by promoting ubiquitination degradation of Runx2. Notably, miR-25 secreted by BMSC-Exo can accelerate osteogenic differentiation, proliferation, and migration of osteoblasts through SMURF1/Runx2 axis. Our results demonstrate that miR-25 in BMSC-Exo regulates the ubiquitination degradation of Runx2 by SMURF1 to promote fracture healing in mice.

Occipitocervical fusion combined with 3-dimensional navigation and 3-dimensional printing technology for the treatment of atlantoaxial dislocation with basilar invagination: A case report.

INTRODUCTION: Basilar invagination (BI) is a common deformity in the occipitocervical region. The traditional surgical method of BI is direct transoral decompression followed by posterior decompression and fixation. Posterior-only decompression and fixation have achieved good efficacy in the treatment of BI in recent years, but complications are common due to the operation in the upper cervical vertebra and the medulla oblongata region. Moreover, posterior-only occipitocervical fusion combined with an intraoperative 3-dimensional (3D) navigation system is relatively rare, and reports of this procedure combined with 3D printing technology have not been published. We present a case of BI treated with posterior-only occipitocervical fusion combined with 3D printing technology and 3D navigation system to reduce the risk of surgical complications. PATIENT CONCERNS: A 55-year-old patient with a history of neck pain and numbness of the extremities for 6 years developed a walking disorder for 1 year. DIAGNOSES: Atlantoaxial dislocation with BI. INTERVENTIONS: The patient underwent posterior-only occipitocervical fusion combined with intraoperative 3D navigation system and 3D printing technology. OUTCOMES: The patient's walking disorder was resolved and he was able to walk approximately 100 m by himself when he was allowed to get up and move around with the help of a neck brace. At 6 months postoperatively, the patient reported that the numbness of the limbs was reduced, and he could walk >500 m by himself. CONCLUSION: Occipitocervical fusion is one of the established techniques for the treatment of BI. The biggest advantage of the 2 technologies was that it ensured precise implant placement. The advantages of intraoperative 3D navigation systems are as follows: real-time intraoperative monitoring of the angle and depth of implant placement; the best nailing point can be determined at the time of implantation, rather than according to the operator's previous experience; and the extent of screw insertion is visible to the naked eye, rather than being dependent on the "hand feel" of the surgeon. At the same time, the 3D printing technology can be applied to clarify the relationship between blood vessels and bone around the implant to minimize injury to important structures during implantation.

Aberrantly Methylated and Expressed Genes as Prognostic Epigenetic Biomarkers for Colon Cancer.

This study aimed to identify prognostic epigenetic biomarkers for colon cancer (CC). Methylation and mRNA expression in CC samples with clinical characteristics that corresponded to those in The Cancer Genome Atlas were analyzed. Differentially methylated genes (DMGs) and differentially expressed genes (DEGs) were screened between matched tumor and nontumor tissues. Among the 415 DEGs and DMGs that significantly correlated between cytosine-phosphate-guanine (CpG) methylation and gene expression, unc-5 netrin receptor C (UNC5C), solute carrier family 35 member F (SLC35F)1, Ly6/Neurotoxin (LYNX)1, stathmin (STMN)2, slit guidance ligand (SLIT)3, cell adhesion molecule L1 like (CHL1), CAP-Gly domain containing linker protein family member 4 (CLIP4), transmembrane protein (TMEM) 255A, granzyme B (GZMB), and brain expressed X-Linked (BEX)1 were promising epigenetic biomarkers. Prediction was more accurate when models were based on the expression and/or methylation of GZMB rather than clinical stage. Comparisons of tissues with high or low GZMB expression significantly associated the DEGs with natural killer-mediated cytotoxicity, cytokine-cytokine receptor interactions, and chemokine signaling pathways. From among the 10 epigenetic biomarkers, GZMB might serve as a tumor suppressor and function in several immune-related pathways in CC. Prognostic models based on GZMB expression and/or methylation would be significant for patients with CC.

Blockade of AT1 receptor partially restores vasoreactivity, NOS expression, and superoxide levels in cerebral and carotid arteries of hindlimb unweighting rats.

Previous studies have demonstrated activation of the local renin-angiotensin system in hindlimb unweighting (HU) rat vasculature. The present study intended to identify the effects of blockade of angiotensin II (ANG II) type 1 (AT(1)) receptors with losartan on vascular reactivity, nitric oxide synthase (NOS) expression, and superoxide anion (O(2)(*-)) levels in 3-wk HU rat cerebral and carotid arteries. Three weeks later, vasoconstriction, vasodilatation, endothelial NOS (eNOS) and inducible NOS (iNOS) protein, as well as O(2)(*-) levels in rat cerebral and carotid arteries were examined. We found that HU enhanced maximal response to KCl/5-hydroxytryptamine (P < 0.01) in basilar arteries and KCl/phenylephrine (P < 0.05) in common carotid arteries from HU rats. Acetylcholine induced concentration-dependent vasodilatation in all the artery rings, but with significantly smaller amplitude in basilar (P < 0.01) and common carotid (P < 0.05) arteries from HU rats than those from control rats. Chronic treatment with losartan partially restored response to vasoconstrictors and acetylcholine-induced vasodilatation in basilar (P < 0.01) and common carotid (P < 0.05) arteries from losartan-treated HU rats. Furthermore, iNOS content in cerebral arteries and eNOS/iNOS content in carotid arteries were significantly (P < 0.01) increased in HU rats. Meanwhile, HU increased O(2)(*-) levels in all the layers of these arteries. However, losartan restored NOS content and O(2)(*-) levels toward normal. These results suggested that the HU-induced enhancement of vasoconstriction and reduction in endothelium-dependent relaxation involved alterations in O(2)(*-) and NOS content through an ANG II/AT(1) receptor signaling pathway.

Post-thawing metabolite profile and amino acid oxidation of thawed pork tenderloin by HVEF-A short communication.

The post-thawing quality, metabolite profile and amino acid oxidation of frozen pork tenderloin following the use of a high-voltage electrostatic field (HVEF) were investigated in this study. There were not significant differences of pH for pork thawed by air and HVEF, which were consistent with the lactic acid level and glycogen content. No changes in the tenderness of thawed pork were found. There were only 6 volatiles with different contents in the pork tenderloin (P < 0.05). Moreover, there were no oxidized cysteine and methionine residues in myosin of thawed pork by HVEF. A total of 23 discriminating metabolites between the air-thawed and HVEF-thawed pork after orthogonal partial least squares-discriminate analysis (OPLS-DA). There were 10 pathways containing >5 discriminating metabolites, among them, there were 10 discriminating metabolites in the glycerophospholipid metabolism (ssc00564) and retrograde endocannabinoid signaling (ssc04723). The glycerophospholipid metabolism could be related to the pork spoilage processes.

DIDS attenuates staurosporine-induced cardiomyocyte apoptosis by PI3K/Akt signaling pathway: activation of eNOS/NO and inhibition of Bax translocation.

AIMS: 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), a non-selective chloride channel blocker, has been shown to prevent cell apoptosis, however, the underlying mechanisms remain undefined, thus the present study was to explore whether phosphatidylinositol 3'-kinase (PI3K)/Akt and its downstream molecules are involved in the cytoprotective effect of DIDS. METHODS: Neonatal rat cardiomyocytes were exposed to staurosporine (STS) in the presence or absence of DIDS. Cell viability, apoptosis and expressions of Akt, phospho-Akt (p-Akt), eNOS, phospho-eNOS (p-eNOS), Bcl-2/Bax and nitric oxide (NO) production were determined, and Bax translocation was assessed by double immunofluorescence labeling and Western blotting. RESULTS: DIDS markedly improved cell viability and exerted an anti-apoptotic effect on STS-exposed cardiomyocytes. DIDS resulted in a 2.1-fold increase of p-Akt over control levels, prevented the reduction in eNOS expression and phospho-eNOS levels induced by STS and significantly increased NO production (all P<0.01 vs. STS alone). Treatment with LY294002, a selective PI3K inhibitor, abolished DIDS-induced increases in p-Akt, eNOS, p-eNOS and NO production, and completely abrogated the DIDS-induced anti-apoptotic effect (P<0.01). Treatment with L-NAME, a non-selective NOS inhibitor similarly inhibited the increased NO but only partly abolished protective effects of DIDS (P<0.05). In addition, DIDS effectively inhibited STS-induced Bax translocation to mitochondria, which was also reversed by LY294002. CONCLUSION: DIDS protects cardiomyocytes against STS-induced apoptosis via activating PI3K/Akt signaling pathway, including increasing eNOS phosphorylation and the subsequent NO production and inhibiting Bax translocation.

Nitric oxide induces heat shock protein 72 production and delayed protection against myocardial ischemia in rabbits via activating protein kinase C.

BACKGROUND: Nitric oxide (NO) is a biologically active molecule which has been reported to protect the heart against ischemia and reperfusion injury in different species. This study aimed to test the hypothesis that nitric oxide may induce the expression of heat shock protein 72 (HSP72) which may protect the heart against ischemia. METHODS: Rabbits were given intravenous saline or S-nitroso-N-acetylpenicillamine (SNAP), a nitric oxide donor, or Zaprinast, an inhibitor of cyclic guanosine monophosphate (GMP)-phosphodiesterase, which may increase myocardial cyclic GMP content. Twenty-four hours later, the rabbits were either sampled to measure HSP72, or induced with a 30-minute coronary occlusion followed by a 120-minute reperfusion, and then the infarct size was measured. Meanwhile, chelerythrine (CHE, an inhibitor of protein kinase C) was given intravenously 5 minutes before SNAP injection and the effect on HSP72 expression and infarct size was determined. RESULTS: Twenty-four hours after pretreatment, immunoblotting showed HSP72 expression increased in the SNAP group compared with control groups, and this was blocked by CHE. Myocardial infarct size in the SNAP group was smaller than that of the control group ((32.4 +/- 5.8)% vs (51.1 +/- 4.7)%, P < 0.05). Pretreated with CHE abolished the infarct size-limiting effect of SNAP ((46.0 +/- 5.1)%). Pretreatment with Zaprinast neither induced HSP72 expression nor reduced infarct size ((55.4 +/- 5.4)%). CONCLUSION: NO induced HSP72 expression and a delayed protection to the heart via the activities of protein kinase C by a cyclic GMP-independent pathway.

Physicochemical changes in myofibrillar proteins extracted from pork tenderloin thawed by a high-voltage electrostatic field.

The application of a high-voltage electrostatic field (HVEF) is a novel method for thawing. To determine the effects of HVEF thawing (voltage range: -25kV to 0kV) on myofibrillar protein oxidation and/or denaturation and to provide a theoretical understanding of this process, pork tenderloin was thawed by traditional and HVEF methods. Based on the total sulfhydryl and carbonyl contents, further protein oxidation did not occur during HVEF thawing. It was proposed that the free radical-mediated oxidation of myofibrillar proteins was hindered by HVEF. The results of dynamic rheological analysis, protein aggregation and gel texture studies showed that HVEF thawing, especially -10kV HVEF thawing, led to better indicators than those achieved under air thawing. A higher abundance of proteins extracted from -10kV HVEF-thawed samples compared with air-thawed samples was found. Finally, this study showed that thawing under -10kV conditions did not affect the structure of myofibrillar proteins.

Alpha-linolenic acid attenuates high glucose-induced apoptosis in cultured human umbilical vein endothelial cells via PI3K/Akt/eNOS pathway.

OBJECTIVE: High glucose-induced apoptosis in vascular endothelial cells contributes to the acceleration of atherosclerosis associated with diabetes. We hypothesized that alpha-linolenic acid (ALA) might attenuate high glucose-induced apoptosis in cultured human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were cultured at 5.5 and 33 mmol/L for 72 h. ALA with different concentrations was added with defatted bovine serum albumin as a carrier for 18 h before incubation with high glucose. RESULTS: Exposure of HUVECs to high glucose media for 72 h significantly increased the number of apoptotic cells compared with normal glucose control, as evaluated by flow cytometry and terminal deoxyuridine triphosphate nick end labeling assay. Pretreatment with low concentrations of ALA (10, 50, and 100 micromol/L) significantly attenuated high glucose-induced apoptosis of HUVECs, but increasing ALA to 200 micromol/L exerted the opposite effect. Furthermore, high glucose reduced phosphorylation of Akt and endothelial nitric oxide synthase (eNOS) with subsequent nitric oxide production, whereas ALA treatment attenuated the reduction caused by high glucose. Pretreatment with phosphatidylinositol 3' -kinase kinase inhibitor LY294002 and eNOS inhibitor N(G)-nitro-arginine methyl ester eliminated ALA' antiapoptotic effect. CONCLUSION: ALA exerts an antiapoptotic effect by the phosphatidylinositol 3'-kinase/Akt/eNOS pathway in HUVECs exposed to high glucose and thus may represent a candidate therapeutic agent for diabetic cardiovascular complications.