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1.
Environ Technol ; : 1-13, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38118136

ABSTRACT

ABSTRACTThe problem of wastewater pollution in the production of monosodium glutamate (MSG) is becoming more and more serious. A novel type of chemically modified Salix psammophila powder charcoal (SPPCAM) was synthesized to address the chemical oxygen demand (COD) and ammonia nitrogen (NH3-N) in MSG wastewater. SPPCAM was prepared by carbonization method, in which inorganic ammonium molybdate (AM) was used as modifier and Salix psammophila powder (SPP) was used as raw material. Under optimal treatment conditions, maximum removal rates (removal capacities) of 45.9% (3313.2 mg·L-1) for COD and 29.4% (23.2 mg·L-1) for NH3-N in MSG wastewater were achieved. The treatment results significantly outperforming the unmodified Salix psammophila powder charcoal (SPPC), which only achieved removal rates (removal capacities) of 10.6% (763.9 mg·L-1) for COD and 12.9% (10 mg·L-1) for NH3-N. SPPC and SPPCAM before and after preparation were analysed by FT-IR and XRD, and Mo ions in the form of Mo2C within SPPCAM were successfully loaded. SEM, EDS-Mapping, BET, and other methods were used to analyse SPPCAM before and after MSG wastewater treatment, demonstrating that SPPCAM effectively treated organic pollutants in monosodium glutamate wastewater. The NH3-N in the treated MSG wastewater has reached the standard of safe discharge.

2.
J Cancer Res Clin Oncol ; 149(11): 8545-8555, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37093348

ABSTRACT

BACKGROUND: Intra-tumor heterogeneity (ITH) contributes to lung cancer progression and resistance to therapy. To evaluate ITH and determine whether it may be employed as a predictive biomarker of prognosis in patients with advanced non-small cell lung cancer (NSCLC), we used a novel algorithm called mutant-allele dispersion (MAD). METHODS: In the study, 103 patients with advanced NSCLC were enrolled. Using a panel of 425 cancer-related genes, next-generation sequencing (NGS) was performed on tumor specimens that had been collected. From NGS data, we derived MAD values, and we next looked into their relationships with clinical variables and different mutation subtypes. RESULTS: The median MAD among 103 NSCLC patients was 0.73. EGFR mutation, tyrosine kinase inhibitor (TKI) therapy, radiotherapy, and chemotherapy cycles were all substantially correlated with the MAD score. In patients with lung adenocarcinoma (LUAD), correlation analysis revealed that the MAD score was substantially linked with Notch pathway mutation (P = 0.021). A significant relationship between high MAD and shorter progression-free survival (PFS) was found (HR = 2.004, 95%CI 1.269-3.163, P = 0.003). In patients with advanced NSCLC, histological type (P = 0.004), SMARCA4 mutation (P = 0.038), and LRP1B mutation (P = 0.006) were all independently associated with prognosis. The disease control rate was considerably greater in the low MAD group compared to the high MAD group in 19 LUAD patients receiving immunotherapy (92.9% vs. 40%, P = 0.037). TKI-PFS was longer in 37 patients with low MAD who received first-line TKI therapy (P = 0.014). CONCLUSION: Our findings suggested that MAD is a practical and simple algorithm for assessing ITH, and populations with high MAD values are more likely to have EGFR mutations. MAD can be used as a potential biomarker to predict not only the prognosis of NSCLC but also the efficacy of immunotherapy and TKI therapy in patients with advanced NSCLC.


Subject(s)
Adenocarcinoma of Lung , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Alleles , Protein Kinase Inhibitors/pharmacology , Prognosis , Adenocarcinoma of Lung/genetics , Mutation , ErbB Receptors/genetics , DNA Helicases/genetics , Nuclear Proteins/genetics , Transcription Factors/genetics
3.
Food Res Int ; 163: 112118, 2023 01.
Article in English | MEDLINE | ID: mdl-36596087

ABSTRACT

Roasting is an important operation to produce attractive colors and distinctive flavors during the production of sesame oil. To investigate the contributions of macromolecules to the color and flavor during roasting sesame seeds, water-soluble polysaccharides (WSP) and chelator-soluble polysaccharides (CSP) sequentially extracted from sesame hull were mixed with sesame protein isolate (SPI) at different ratios (1:1, 1:2, and 2:1, w/w), then the mixtures were roasted at 180 °C for 35 min. Results showed that WSP, CSP, and SPI degraded approximately at 150 °C and SPI had the highest thermal stability. According to monosaccharide/amino acid analysis, glucose and galacturonic acid showed the highest reduction rates, as well as lysine and arginine. CSP + SPI mixtures showed greater reactivity than WSP + SPI mixtures, resulting in a darker color and many more Maillard reaction products. The predominant volatiles of roasted WSP/CSP + SPI mixtures were aldehydes and heterocyclic compounds identified by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS). This work provides some new information about flavor and color development during roasting sesame seeds.


Subject(s)
Sesamum , Gas Chromatography-Mass Spectrometry , Seeds/chemistry , Sesame Oil/chemistry , Sesamum/chemistry
4.
Food Chem X ; 16: 100483, 2022 Dec 30.
Article in English | MEDLINE | ID: mdl-36304205

ABSTRACT

In this work, sesame oligosaccharides (SOL) and sesame protein isolate (SPI) were isolated from dehulled sesame meal, combined and then tested as a sesame model system, to investigate the effects of roasting temperature and duration on color and flavor. The results demonstrated that SOL was more easily degraded than SPI; specifically, SOL and SPI gradually degraded at 100 °C and 150 °C, respectively. FT-IR analysis showed that characteristic bonds existing in the roasted samples were somewhat destroyed. Galactose, fructose, lysine, cysteine, and arginine showed great reduction and played an important role in color variation and flavor compound formation according to monosaccharide and amino acid analysis. Total color difference (ΔE) and browning intensity increased with roasting temperature and roasting duration. The types and concentrations of volatile flavor compounds were significantly increased, particularly heterocyclics (14.1 %-34.4 %) and phenols (28.4 %-32.4 %), corresponding to 0.3 % and 8.9 % of the unroasted samples.

5.
Theranostics ; 11(16): 7879-7895, 2021.
Article in English | MEDLINE | ID: mdl-34335970

ABSTRACT

Rationale: Previous studies have shown that human embryonic stem cell-derived cardiomyocytes improved myocardial recovery when administered to infarcted pig and non-human primate hearts. However, the engraftment of intramyocardially delivered cells is poor and the effectiveness of clinically relevant doses of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in large animal models of myocardial injury remains unknown. Here, we determined whether thymosin ß4 (Tb4) could improve the engraftment and reparative potency of transplanted hiPSC-CMs in a porcine model of myocardial infarction (MI). Methods: Tb4 was delivered from injected gelatin microspheres, which extended the duration of Tb4 administration for up to two weeks in vitro. After MI induction, pigs were randomly distributed into 4 treatment groups: the MI Group was injected with basal medium; the Tb4 Group received gelatin microspheres carrying Tb4; the CM Group was treated with 1.2 × 108 hiPSC-CMs; and the Tb4+CM Group received both the Tb4 microspheres and hiPSC-CMs. Myocardial recovery was assessed by cardiac magnetic resonance imaging (MRI), arrhythmogenesis was monitored with implanted loop recorders, and tumorigenesis was evaluated via whole-body MRI. Results: In vitro, 600 ng/mL of Tb4 protected cultured hiPSC-CMs from hypoxic damage by upregulating AKT activity and BcL-XL and promoted hiPSC-CM and hiPSC-EC proliferation. In infarcted pig hearts, hiPSC-CM transplantation alone had a minimal effect on myocardial recovery, but co-treatment with Tb4 significantly enhanced hiPSC-CM engraftment, induced vasculogenesis and the proliferation of cardiomyocytes and endothelial cells, improved left ventricular systolic function, and reduced infarct size. hiPSC-CM implantation did not increase incidence of ventricular arrhythmia and did not induce tumorigenesis in the immunosuppressed pigs. Conclusions: Co-treatment with Tb4-microspheres and hiPSC-CMs was safe and enhanced the reparative potency of hiPSC-CMs for myocardial repair in a large-animal model of MI.


Subject(s)
Myocardial Infarction/therapy , Myocytes, Cardiac/metabolism , Thymosin/pharmacology , Animals , Cell Differentiation , Cell Proliferation , Cells, Cultured , China , Disease Models, Animal , Endothelial Cells/pathology , Humans , Induced Pluripotent Stem Cells/metabolism , Myocardial Infarction/metabolism , Myocardium/pathology , Regeneration , Stem Cell Transplantation/methods , Swine , Thymosin/metabolism , Thymosin/physiology
6.
Oecologia ; 196(1): 27-35, 2021 May.
Article in English | MEDLINE | ID: mdl-33825007

ABSTRACT

Identifying intrinsic and extrinsic sources of variation in life history traits among populations has been well-studied at the post-embryonic stage but rarely at the embryonic stage. To reveal these sources of variation in the developmental success of embryos, we measured the physical characteristics of nest environments and conducted reciprocal egg-swap experiments in two populations of the toad-headed agamid lizard (Phrynocephalus przewalskii), isolated from each other by a mountain range. We determined the effects of population origin and nest environment on embryonic and offspring traits related to developmental success, including incubation period, hatching success, and offspring growth and survival. Females from the northern population constructed deeper nests that were colder and wetter than those from the southern population. Northern embryos had higher hatching success than the southern embryos when incubated at the northern nest environment, but not when they were incubated at the southern nest environment. The southern hatchlings grew faster than the northern hatchlings when incubated at the southern nest environment, but not after incubation at the northern nest environment. These phenomena likely reflect local adaptation of embryonic development to their nest environments among populations in lizards. In addition, the southern hatchlings had higher survivorship than the northern hatchlings regardless of nest environment, suggesting the southern population has evolved a superior phenotype at the hatchling stage to maximize its fitness.


Subject(s)
Lizards , Adaptation, Physiological , Animals , Embryonic Development , Female , Phenotype , Temperature
7.
Mol Med Rep ; 22(6): 4725-4733, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33174002

ABSTRACT

Spinal cord injury (SCI) is a devastating disorder that often results in temporary and/or permanent functional impairment below the injured level. To date, few satisfactory therapeutic strategies are available to treat SCI. Hence, exploring novel strategies for SCI is an essential public health concern. Cell transplantation therapy, which is associated with neuroprotection, immunomodulation, axon regeneration, neuronal relay formation and myelin regeneration, provides a promising therapeutic strategy for SCI. The neuronal stem cell (NSC) preconditioning method is an emerging approach, which facilitates NSC survival and neuronal differentiation after implantation. The aim of the present study was to develop a feasible candidate for cell­based therapy following SCI in rats and to investigate the role of high mobility group box­1 (HMGB1) in NSC activation. The results of the present study showed that transplantation of NSCs, preconditioned with 1 ng/ml HMGB1, facilitated functional improvement of injured spinal cords, as indicated by Basso, Beattie and Bresnahan mean scores, mechanical hypersensitivity and cold stimulation. Meanwhile, the histological examination of hematoxylin and eosin staining indicated that engraftment of HMGB1­preconditioned NSCs resulted in decreased atrophy of the injured spinal cord. Meanwhile, the transplantation of HMGB1­preconditioned NSCs resulted in an increased number of functional Nissl bodies in neurons, as detected by Nissl staining, and an increase in the number of ßIII­tubulin+ cells in the epicenter of injured spinal cords in rats with SCI. In addition, the results also demonstrated that 1 ng/ml HMGB1 promoted the differentiation of NSCs into neurons, and that the ERK signaling pathway played an important role in this process. In conclusion, the present data indicated that the preconditioning strategy with 1 ng/ml HMGB1 may present a feasible candidate for cell­based therapy following SCI in rats, which may enlarge the scope of HMGB1 in NSC activation.


Subject(s)
Neural Stem Cells/metabolism , Spinal Cord Injuries/therapy , Stem Cell Transplantation/methods , Animals , Axons/metabolism , Cell Differentiation/physiology , Cell Survival/physiology , HMGB Proteins/metabolism , HMGB1 Protein/metabolism , HMGB1 Protein/therapeutic use , Male , Motor Activity/physiology , Nerve Regeneration/physiology , Neurons/metabolism , Rats , Rats, Sprague-Dawley , Recovery of Function/physiology , Spinal Cord/metabolism
8.
Huan Jing Ke Xue ; 41(11): 5027-5036, 2020 Nov 08.
Article in Chinese | MEDLINE | ID: mdl-33124246

ABSTRACT

In this study, the relative molecular weight distribution and fluorescent characteristics of the organic matter in sediments during the thermal stratification of a drinking water reservoir were studied. The nitrogen removal, growth performance, and carbon removal ability of an aerobic denitrifier were investigated when the organic matter in sediments was used as a carbon source. The results found that:① during the stratification period in the drinking water reservoir, the organic matter in sediments has a larger proportion of relative molecular mass>100×103. It can be observed that compared with the relative molecular weight distribution in different months, the percentage of macromolecular organic matter in sediments is the lowest in July (44.62%), showing a characteristic of smaller relative molecular weight; ② the organic matter in sediments of the drinking water reservoir was composed of terrestrial humic-like substance component C1 (250 nm, 425 nm), tryptophan and amino acid-like substances component C2 (230 nm/280 nm, 322 nm), and traditional microbial humic-like substances component C3 (250 nm, 340 nm). Component C2 accounted for a higher percentage, and the organic matter in July showed a higher total fluorescence intensity; ③ during the aerobic denitrification process, organic matter in May displayed better characteristics as an electron donor, while organic matter in July exhibited excellent performance as an energy substance and better denitrification characteristics of the strain WGX-9; ④ the aerobic denitrification performance of the strain WGX-9 can be significantly promoted when the organic matter in sediments is a carbon source, compared with natural organic matter, algae organic matter, and actual water of the drinking water reservoir. This study clarifies the characteristics of the organic matter in sediments during the thermal stratification period of the drinking water reservoir and its effect on an aerobic denitrifier. This will provide a scientific basis for the research of nitrogen pollution control in micro-polluted water sources.


Subject(s)
Carbon , Nitrogen
9.
Arch Oral Biol ; 118: 104875, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32795622

ABSTRACT

OBJECTIVE: The objective of the present study was to evaluate the accuracy of the Demirjian, Willems, and Nolla methods for dental age estimation on a sample of the northern Chinese population. DESIGN: The study consisted of 2000 panoramic radiographs (1000 boys and 1000 girls) with an age range between 5 and 14 years. The mean error and absolute mean error were calculated according to each method, and the accuracy was statistically analysed. RESULTS: The three methods used for Chinese subjects overestimated the dental age by 1.16, 0.50, and 0.07 years. The absolute mean error was largest in most age groups for the Demirjian method, which was considered inaccurate in age estimation for teenagers, and it was more than 1.00 years for only several age groups for the Willems method and only girls aged 14 years for the Nolla method. The mean error and absolute mean error were lowest for the Nolla method and highest for the Demirjian method. CONCLUSIONS: Although the Demirjian method is frequently used in Chinese subjects for legal and medical purposes, the Willems and Nolla methods were more reliable than the Demirjian method. Among the three methods, the accuracy in the northern Chinese subjects was highest for the Nolla method. Therefore, it is recommended to evaluate the accuracy of different methods before assessing the age in specific populations.


Subject(s)
Age Determination by Teeth/methods , Adolescent , Asian People , Child , Child, Preschool , China , Female , Humans , Male , Radiography, Panoramic
10.
Huan Jing Ke Xue ; 41(5): 2166-2176, 2020 May 08.
Article in Chinese | MEDLINE | ID: mdl-32608834

ABSTRACT

To explore the effect mechanism of the artificial mixing process on the temporal and spatial succession of algae community structure in a water body, this study used water-lifting aerators to induce in-situ artificial mixing of the water body of Jinpen Reservoir, and in-situ spot physical-chemical parameters and algae of the water body of the reservoir were observed during an artificial mixing process. A total of 51 species of 28 genera of 6 families of algae were identified in the water body of the Jinpen Reservoir. The artificial mixing effect of the water-lifting aerators significantly inhibited the growth of algae in the water, and had a significant impact on the community structure. Before activation of the water-lifting aerators, algae were mainly distributed in the surface water body, and Chlorella vulgaris was the dominant species. With the operation of the water-lifting aerators, the algal density of surface water body decreased significantly, and the vertical distribution of the algae density in the water body tended to be uniform. The dominant species tended to succeed in Cyclotella sp. This study used the method of redundancy analysis, combined with critical depth theory and the characteristics of algae growth, to analyze the relationship between the spatial-temporal succession of algae community structure and the changes in the main physical-chemical parameters in Jinpen Reservoir during the artificial process. The analysis results showed that the artificial mixing of the water-lifting aerators mainly affects the temporal and spatial succession of the algae community structure by rapidly destroying the thermal stratification stability of the water body and significantly increasing the water mixing depth.


Subject(s)
Chlorella vulgaris , Diatoms , Water , Water Quality
11.
Huan Jing Ke Xue ; 41(5): 2188-2197, 2020 May 08.
Article in Chinese | MEDLINE | ID: mdl-32608836

ABSTRACT

Aerobic anoxygenic photosynthesis bacteria (AAPB) play a significant role in the material circulation of the hydrosphere, with diverse community structure and unique metabolic functions. To investigate the spatial and temporal succession characteristics of AAPB abundance and community structure in Jinpen Reservoir, a quantitative real-time polymerase chain reaction and Illumina MiSeq high-throughput sequencing technique targeting the pufM gene were applied. Furthermore, redundancy analysis was used to determine the influence of environmental factors on their community structure. The results showed that the AAPB abundance ranged from (6.70±0.43)×103 to (2.69±0.15)×104 copies·mL-1, with the maximum value appearing in October, and decreased with an increase in water depth. Samples were mainly classified into 19 genera (except for the unclassified genus); the most abundant AAPB genera were Bradyrhizobium sp. and Methylobacterium sp., which were affiliated to the α-Proteobacteria, and the proportion of the Bradyrhizobium sp. was highest in November, accounting for more than 60% (except 10 m). Furthermore, Rubrivivax sp., belonging to ß-Proteobacteria, was found to have a low proportion. There was a strong interaction relationship between AAPB genera. For example, Rhodobacter sp. was positively correlated with Rhodovulum sp., while Hydrogenophaga sp. was negatively correlated with Bradyrhizobium sp.. The community structure composition and distribution of AAPB were significantly different, mainly affected by temperature (T), total nitrogen (TN), NO3--N, and light intensity and comprehensively regulated by environmental factors. For instance, T, TN, and total phosphorus had a significant impact on the AAPB community structure of water samples at 0, 5, and 15 m in October, whereas light intensity, pH, DO, and chlorophyll-a were major structuring factors in the AAPB assemblages of water samples at 5 m in December. The results have guiding significance for parsing the spatial and temporal variability of AAPB abundance and diversity in stratified reservoirs, and simultaneously provide a theoretical basis for exploring the driving factors of AAPB population structure.

12.
Huan Jing Ke Xue ; 41(7): 3231-3239, 2020 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-32608896

ABSTRACT

In response to the annual hypolimnetic anoxia in stratified reservoirs, water-lifting aerators (WLAs) were used in Jinpen Reservoir to supplement the dissolved oxygen in the bottom water and suppress the release of reduced pollutants from sediment. However, due to the influence of geomorphic characteristics at the bottom of the reservoir, there were some differences in the efficiency of artificial mixing and aeration. After the deactivation of WLAs, the dissolved oxygen in the bottom water of some deeper areas was rapidly depleted, resulting in the re-release of pollutants. To explore the release mechanisms and diffusion intensity of iron and manganese during this period, the representative samples in the main reservoir area were collected to measure the distribution of dissolved iron and manganese in the pore water and overlying water and calculate the diffusive flux of dissolved iron and manganese across the sediment-water interface. The results showed that the bottom water of the lower terrain rapidly entered the anaerobic condition after the system was deactivated, resulting in the release of a large amount of dissolved manganese into the overlying water, the maximum concentration of which was 0.42 mg·L-1. However, the bottom water of the higher terrain briefly entered a state of hypoxia, after which the dissolved oxygen concentration increased rapidly, so the dissolved manganese concentration increased moderately to 0.17 mg·L-1. The distribution of iron and manganese in the pore-water-overlying water showed that the dissolved manganese was released more easily into the overlying water than the iron under anaerobic conditions and constant accumulation in the upper sediments and overlying water. However, the release of dissolved iron was not only suppressed by dissolved oxygen but also by other oxidants such as manganese oxide. The diffusion flux of dissolved manganese declined after the system was deactivated. A mass balance calculation demonstrated that the accumulation of dissolved manganese in the anaerobic layer was not only related to the diffusion flux but also to the sedimentation flux and the thickness of the anaerobic layer. Therefore, the biogeochemical cycle of iron and manganese in the anaerobic layer requires further study.

13.
Chem Biodivers ; 16(11): e1900357, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31573145

ABSTRACT

The ginger extract obtained with supercritical CO2 fluid was purified by molecular distillation (MD), and the chemical compositions, antioxidant and cytotoxic activities of ginger extract and its distillates were investigated. Analysis revealed that the ginger extract was rich in terpene hydrocarbons, along with oxygenated terpenes and other non-volatile compounds. The MD distillates were prepared in a series of stages and the active compounds like terpenes and gingerols could be separated by MD. The major compounds of the distillates purified by MD at 40 °C, 80 Pa and 60 °C, 80 Pa were terpene hydrocarbons. Additional distillates obtained by MD at 80 °C, 80 Pa and 100 °C, 60 Pa were predominated by terpene hydrocarbons and oxygenated terpenes. Until the operating conditions of MD reached 150 °C and 2 Pa, some non-volatile compounds were concentrated in the final distillate. Moreover, antioxidant activities and the cytotoxic effects on three human cancer cells in final MD distillate were superior to other extracts, and this phenomenon could be mainly supported by the phenols. The MD could be used to prepare ginger distillates with better antioxidant and cytotoxic activities.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Antioxidants/pharmacology , Biphenyl Compounds/antagonists & inhibitors , Carbon Dioxide/chemistry , Picrates/antagonists & inhibitors , Plant Extracts/chemistry , Plant Extracts/pharmacology , Zingiber officinale/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antioxidants/chemistry , Antioxidants/isolation & purification , Cell Proliferation/drug effects , Distillation , Drug Screening Assays, Antitumor , Gas Chromatography-Mass Spectrometry , Humans , Plant Extracts/isolation & purification , Tumor Cells, Cultured
14.
Circulation ; 138(24): 2798-2808, 2018 12 11.
Article in English | MEDLINE | ID: mdl-30030417

ABSTRACT

BACKGROUND: The adult mammalian heart has limited ability to repair itself after injury. Zebrafish, newts, and neonatal mice can regenerate cardiac tissue, largely by cardiac myocyte (CM) proliferation. It is unknown whether hearts of young large mammals can regenerate. METHODS: We examined the regenerative capacity of the pig heart in neonatal animals (ages 2, 3, or 14 days postnatal) after myocardial infarction or sham procedure. Myocardial scar and left ventricular function were determined by cardiac magnetic resonance imaging and echocardiography. Bromodeoxyuridine pulse-chase labeling, histology, immunohistochemistry, and Western blotting were performed to study cell proliferation, sarcomere dynamics, and cytokinesis and to quantify myocardial fibrosis. RNA-sequencing was also performed. RESULTS: After myocardial infarction, there was early and sustained recovery of cardiac function and wall thickness in the absence of fibrosis in 2-day-old pigs. In contrast, older animals developed full-thickness myocardial scarring, thinned walls, and did not recover function. Genome-wide analyses of the infarct zone revealed a strong transcriptional signature of fibrosis in 14-day-old animals that was absent in 2-day-old pigs, which instead had enrichment for cytokinesis genes. In regenerating hearts of the younger animals, up to 10% of CMs in the border zone of the myocardial infarction showed evidence of DNA replication that was associated with markers of myocyte division and sarcomere disassembly. CONCLUSIONS: Hearts of large mammals have regenerative capacity, likely driven by cardiac myocyte division, but this potential is lost immediately after birth.


Subject(s)
Heart/physiology , Myocardial Infarction/pathology , Animals , Animals, Newborn , Cytokinesis/genetics , Echocardiography , Fibrosis , Magnetic Resonance Imaging, Cine , Myocardial Infarction/diagnostic imaging , Myocardium/pathology , Myocytes, Cardiac/physiology , Regeneration , Swine , Troponin I/analysis , Ventricular Function, Left
15.
PLoS One ; 8(7): e68796, 2013.
Article in English | MEDLINE | ID: mdl-23861942

ABSTRACT

It is well-established that hyperthermia increases neuronal death and worsens stroke outcome. However, little is known about the mechanisms of how hyperthermia is involved in this neuronal death process. In the present study, we examined how temperature increase exacerbates neuronal death using a model of chemical ischemia. Chemical ischemia was induced by treating SH-SY5Y neuroblastoma cells with sodium azide and deoxyglucose. Temperature increase was treated by placing the cells at 37°C (control) and 41°C (experimental). Cell survival was determined by trypan blue assay and ATP levels were measured with ATP assay kits. Protein expression was detected by western blot. Treatment with sodium azide resulted in cell death in a dose-responsive manner. Increased temperature worsened the ATP depletion and cell volume shrinkage. Temperature increase also enhanced ER stress as demonstrated by the elevated level of phospho-eIF2α and C/EBP homologous protein (CHOP). Inhibition of CHOP expression significantly decreased sodium azide-induced neuronal death. In addition, the increased temperature intensified the activation of caspase-3, an apoptotic effector protease, and inhibition of capspase-3 significantly reduced cell death. These findings support that temperature increase worsened the neuronal death by depleting intracellular ATP, inducing ER stress response and activating apoptotic signal transduction.


Subject(s)
Apoptosis/drug effects , Ischemia/chemically induced , Ischemia/pathology , Temperature , Adenosine Triphosphate/metabolism , Caspase 3/metabolism , Caspase Inhibitors/pharmacology , Cell Line, Tumor , Deoxyglucose/toxicity , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum Stress/drug effects , Enzyme Activation/drug effects , Extracellular Space/metabolism , Humans , Intracellular Space/metabolism , Ischemia/enzymology , Signal Transduction , Sodium Azide/toxicity
16.
Int J Hyperthermia ; 28(1): 24-32, 2012.
Article in English | MEDLINE | ID: mdl-22235782

ABSTRACT

PURPOSE: Basal lamina is a major part of the microvascular wall and plays a critical role in the integrity of microvasculature. The aim of this study is to determine whether hyperthermia worsens the destruction of microvascular integrity in the ischaemic injured brain. MATERIALS AND METHODS: Focal cerebral ischaemia was induced by embolising a pre-formed clot into the middle cerebral artery (MCA). Rats received either normothermic or hyperthermic treatment. Neurological score and infarct size were evaluated at 24 h after the MCA occlusion. Microvascular collagen type IV and laminin were measured with fluorescence microscopy. The activities of matrix metalloproteinases (MMP-2 and MMP-9) and plasminogen activators (tPA and uPA) were determined by zymography. RESULTS: Treatment with hyperthermia significantly increased infarct volume (p<0.01), cortex swelling (p<0.01), striatum swelling (p<0.05) and neurologic score (p<0.01) at 24 h after the MCA occlusion. Compared to the normothermic groups, hyperthermia significantly worsened the losses of microvascular basal lamina structure proteins, collagen type IV and laminin, at 6 h (p<0.001) and 24 h (p<0.01) after MCA occlusion. Hyperthermia increased the MMP-9 activity at 6 and 24 h after MCA occlusion compared with normothermia (p<0.05), whereas increased the MMP-2 activity at 6 h only (p<0.05). Hyperthermia also elevated uPA activity significantly at 6 and 24 h after MCA occlusion compared to normothermia (p<0.05). CONCLUSIONS: These results demonstrate that hyperthermia exacerbates the destruction of microvascular integrity possibly by increasing the activities of MMP-2, MMP-9 and uPA in the ischaemic cerebral tissues.


Subject(s)
Basement Membrane/blood supply , Brain Infarction/pathology , Brain Ischemia/pathology , Hyperthermia, Induced/adverse effects , Microvessels/pathology , Animals , Basement Membrane/pathology , Behavior, Animal , Brain Infarction/physiopathology , Brain Ischemia/physiopathology , Cerebral Cortex/blood supply , Cerebral Cortex/pathology , Collagen Type IV/metabolism , Corpus Striatum/blood supply , Corpus Striatum/pathology , Disease Models, Animal , Laminin/metabolism , Male , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Plasminogen Activators/metabolism , Rats , Rats, Sprague-Dawley
17.
J Neurosci Methods ; 187(1): 8-12, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-20005255

ABSTRACT

Cerebrospinal fluid (CSF) is in direct contact with the extracellular space in the central nervous system (CNS), and biological changes in the brain can be reflected in CSF. In the present article, a procedure for collection of CSF in rats is described. The technique quickly and reliably yields large quantities of CSF (50-150 microl) in rats. More importantly, blood contamination of the CSF is avoided. Furthermore, detections of ATP and interleukin (IL)-1 beta in the CSF have been carried out. ATP concentration in the CSF samples was between 8.3 and 15.8 nM, with an average of 10.5+/-0.83 nM (mean+/-SEM). The concentrations of IL-1beta were below the detection limit in the CSF in the laminectomy control rats, but it increased to 0.26+/-0.07 ng/ml at 1h after spinal cord injury. This technique offers an alternative method to surgical cannulation for the collection of CSF in rats.


Subject(s)
Cerebrospinal Fluid , Cisterna Magna , Specimen Handling/methods , Adenosine Triphosphate/cerebrospinal fluid , Animals , Blood , Brain Stem/pathology , Cerebrospinal Fluid/chemistry , Enzyme-Linked Immunosorbent Assay , Interleukin-1beta/cerebrospinal fluid , Laminectomy , Male , Neuropsychological Tests , Rats , Rats, Sprague-Dawley , Spinal Cord Injuries/cerebrospinal fluid , Time Factors
18.
J Neuroimaging ; 20(3): 272-6, 2010 Jul.
Article in English | MEDLINE | ID: mdl-19888934

ABSTRACT

Reperfusion with intravenous tissue plasminogen activator (tPA) has been the goal of therapy for acute ischemic stroke; however, tPA is contraindicated in many patients, has low recanalization rates in major occlusions, and carries a substantial risk of symptomatic intracerebral hemorrhage. In the present study, we hypothesized that partial intra-aortic occlusion of the abdominal aorta would increase salvage of ischemic penumbra and reduce infarct volume after focal embolic stroke in rats. We examined the effects of aortic occlusion on infarct volume, expression and activation of matrix metalloprotease-9, and hemorrhagic transformation with or without treatment with tPA. We then examined the effects of aortic occlusion on perfusion deficits following embolic occlusion. Results showed that partial aortic occlusion significantly reduces brain infarction volume with or without treatment with tPA after focal ischemia, but does not increase risk for hemorrhagic transformation or matrix metalloprotease-9 expression and activation. Partial intra-aortic occlusion also reduces perfusion deficits after focal cerebral ischemia as compared to control. The present study shows that partial intra-aortic occlusion significantly decreases infarction volume and perfusion deficits following ischemic injury in an embolic model of cerebral ischemia. Moreover, combination treatment with tPA and partial intra-aortic occlusion further reduces infarction volume without any increase in hemorrhagic transformation.


Subject(s)
Aorta , Balloon Occlusion , Brain Ischemia/pathology , Brain Ischemia/therapy , Brain/pathology , Analysis of Variance , Animals , Brain/metabolism , Brain Ischemia/metabolism , Male , Matrix Metalloproteinase 9/metabolism , Rats , Rats, Sprague-Dawley
19.
J Cereb Blood Flow Metab ; 29(10): 1683-94, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19553906

ABSTRACT

In this study, we examined whether rosiglitazone, a peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, is neuroprotective in focal ischemic brain injury, and whether rosiglitazone can enhance the protective action of tissue plasminogen activator (tPA), an agent used clinically for thrombolytic therapy. Rats were subjected to ischemic brain injury by embolizing preformed clots into the middle cerebral artery (MCA). Treatment with rosiglitazone reduced infarction and improved functional recovery; it also enhanced the neuroprotective action of tPA and lengthened the time window for initiating tPA treatment. Occlusion of MCA resulted in a loss of collagen type IV, a major structural protein of the microvascular basal lamina, and tPA treatment worsened this loss. Rosiglitazone treatment prevented the reduction of collagen type IV in the ischemic injured brain by inhibiting the activation of matrix metallopeptidase-9 (MMP-9). In addition, rosiglitazone treatment reduced inflammatory reactions in the ischemic injured brain. Rosiglitazone either alone or in combination with tPA is an effective agent in the reduction of ischemic brain injury. The reduction of microvascular damage and inflammation contributes to the beneficial actions of rosiglitazone.


Subject(s)
Brain Ischemia/drug therapy , Thiazolidinediones/pharmacology , Tissue Plasminogen Activator/pharmacology , Animals , Collagen Type IV/drug effects , Disease Models, Animal , Drug Therapy, Combination , Embolism/complications , Hypoglycemic Agents , Matrix Metalloproteinase 9/drug effects , Middle Cerebral Artery , Neuroprotective Agents , PPAR gamma/antagonists & inhibitors , Rats , Rosiglitazone , Thiazolidinediones/administration & dosage , Tissue Plasminogen Activator/administration & dosage , Treatment Outcome
20.
J Neurosurg ; 109(3): 522-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18759586

ABSTRACT

OBJECT: Statins have been used for induction of ischemic tolerance after cerebral ischemia. The authors have previously shown that simvastatin is protective after ischemic cerebral injury in normothermic conditions. In this study they further examined whether treatment with simvastatin can reduce ischemic brain injury in a hyperthermic condition. METHODS: Focal ischemic brain injury was induced by embolizing a preformed clot into the middle cerebral artery in rats. The authors initially examined whether treatment with simvastatin could reduce ischemic brain injury without or with hyperthermia. The infarct volume, edema, and neurological deficits were examined. They then studied whether simvastatin could reduce the perfusion deficits, damage to the blood-brain barrier (BBB), and degeneration of neurons in the ischemic injured brain. RESULTS: Simvastatin significantly reduced the infarct volume in both normothermic and hyperthermic conditions, compared with appropriate controls. Concomitantly, this treatment also significantly reduced neurological deficits and brain edema. Administration of simvastatin significantly decreased perfusion deficits, BBB permeability, and degenerated neurons. CONCLUSIONS: These studies suggest that simvastatin is an effective agent for ischemic brain injury not only in normothermic but also in hyperthermic conditions, which may be through the decrease of BBB permeability, degenerated neurons, and perfusion deficits.


Subject(s)
Brain Ischemia/prevention & control , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hyperthermia, Induced , Simvastatin/administration & dosage , Animals , Brain Edema/pathology , Brain Edema/physiopathology , Brain Edema/prevention & control , Brain Ischemia/pathology , Brain Ischemia/physiopathology , Cerebrovascular Circulation , Combined Modality Therapy , Disease Models, Animal , Male , Rats , Rats, Sprague-Dawley
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