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1.
Hepatology ; 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34510484

RESUMO

OBJECTIVES: Aging exacerbates liver neutrophil infiltration and alcohol-associated liver disease (ALD) in mice and humans, but the underlying mechanisms remain obscure. This study aimed to examine the effect of aging and alcohol consumption on neutrophilic Sirtuin 1 (SIRT1) and microRNA-223 (miR-223), and their contribution to ALD pathogeneses. DESIGN: Young and aged mice, myeloid-specific Sirt1 knockout mice were subjected to chronic-plus-binge ethanol feeding. Blood samples from healthy controls and patients with chronic alcohol drinking presented with acute intoxication were analyzed. RESULTS: Neutrophilic Sirt1 and miR-223 expression were downregulated in aged mice compared to young mice. Deletion of the Sirt1 gene in myeloid cells including neutrophils exacerbated chronic-plus-binge ethanol-induced liver injury and inflammation and downregulated neutrophilic miR-223 expression. Immunoprecipitation experiments revealed that SIRT1 promoted C/EBPα deacetylation by directly interacting with C/EBPα, a key transcription factor that controls miR-223 biogenesis, and subsequently elevated miR-223 expression in neutrophils. Importantly, downregulation of SIRT1 and miR-223 expression was also observed in circulating neutrophils from middle-aged and elderly subjects compared to those from young individuals. Chronic alcohol users with acute intoxication had a reduction in neutrophilic SIRT1 expression in young and middle-aged patients, with a greater reduction in the latter group. The neutrophilic SIRT1 expression correlated with neutrophilic miR-223 and serum alanine transaminase levels in those patients. CONCLUSIONS: Aging increases the susceptibility of alcohol-induced liver injury in mice and humans via the downregulation of the neutrophilic SIRT1-C/EBPα-miR-223 axis, which could be a novel therapeutic target for the prevention and/or treatment of ALD.

2.
Adv Mater ; : e2104090, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34510607

RESUMO

Carbon-supported single-atom catalysts (SACs) are extensively studied because of their outstanding activity and selectivity toward a wide range of catalytic reactions. Amidst its development, excess dopants (e.g., nitrogen) are always required to ensure the high loading content of SACs on the carbon support. However, the use of excess dopants is accompanied by formation of miscellaneous structures (particularly the uncoordinated N species) on catalysts, leading to adverse effects on their performance. Herein, the synthesis of carbon-supported Ni SACs with precisely controlled single-atom structure via joule heating strategy, showing the coordination of 80% of N dopants with metal elements, is reported. The preclusion of the unfavorable N species is confirmed to be the main reason for the superior performance of optimized Ni SACs in electrocatalytic carbon dioxide reduction reaction, which demonstrates unprecedented activity, selectivity, and stability under an exceptionally broad voltage range (>92% CO selectivity in the range of -0.7 to -1.9 V reversible hydrogen electrode). Such a synthetic strategy is further applicable for the design of SACs with various metals. This work demonstrates a facile method for preclusion of unfavorable dopants in the SACs and its importance in catalytic application.

3.
J Neuroinflammation ; 18(1): 205, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34530848

RESUMO

BACKGROUND: Two activation states of reactive astrocytes termed A1 and A2 subtypes emerge at the lesion sites following spinal cord injury (SCI). A1 astrocytes are known to be neurotoxic that participate in neuropathogenesis, whereas A2 astrocytes have been assigned the neuroprotective activity. Heat shock transcription factor 1 (HSF1) plays roles in protecting cells from stress-induced apoptosis and in controlling inflammatory activation. It is unknown whether HSF1 is involved in suppressing the conversion of A1 astrocytes following SCI. METHODS: A contusion model of the rat spinal cord was established, and the correlations between HSF1 expression and onset of A1 and A2 astrocytes were assayed by Western blot and immunohistochemistry. 17-AAG, the agonist of HSF1, was employed to treat the primary cultured astrocytes following a challenge by an A1-astrocyte-conditioned medium (ACM) containing 3 ng/ml of IL-1α, 30 ng/ml of TNF-α, and 400 ng/ml of C1q for induction of the A1 subtype. The effects of 17-AAG on the phenotype conversion of astrocytes, as well as underlying signal pathways, were examined by Western blot or immunohistochemistry. RESULTS: The protein levels of HSF1 were significantly increased at 4 days and 7 days following rat SCI, showing colocalization with astrocytes. Meanwhile, C3-positive A1 astrocytes were observed to accumulate at lesion sites with a peak at 1 day and 4 days. Distinctively, the S100A10-positive A2 subtype reached its peak at 4 days and 7 days. Incubation of the primary astrocytes with ACM markedly induced the conversion of the A1 phenotype, whereas an addition of 17-AAG significantly suppressed such inducible effects without conversion of the A2 subtype. Activation of HSF1 remarkably inhibited the activities of MAPKs and NFκB, which was responsible for the regulation of C3 expression. Administration of 17-AAG at the lesion sites of rats was able to reduce the accumulation of A1 astrocytes. CONCLUSION: Collectively, these data reveal a novel mechanism of astrocyte phenotype conversion following SCI, and HSF1 plays key roles in suppressing excessive increase of neurotoxic A1 astrocytes.

4.
Ann Phys Rehabil Med ; : 101570, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34536570

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction requires an extended period of postoperative rehabilitation. Psychological factors can affect recovery after surgery. Study of psychological factors is still limited to self-motivation, fear and pain. Study of personality traits associated with early rehabilitation outcome after ACL reconstruction is scarce. OBJECTIVE: We aimed to explore the effect of personality traits on early rehabilitation after ACL reconstruction and provide a reference for clinicians in designing a personalized rehabilitation plan. METHODS: This prospective analysis investigated 155 patients at 3 and 6 months after ACL reconstruction. Follow-up involved administration of a general data questionnaire, the Chinese Big Five Personality Inventory Brief Version, the Tegner activity score, the International Knee Documentation Committee Subjective Knee Score, the Knee injury and Osteoarthritis Outcome Score, the Lysholm Score and a balance test. RESULTS: Among the 155 patients included (124 males), Neuroticism was negatively correlated with subjective knee scores at 3 and 6 months after surgery (p<0.001). The odds of a poor balance test result was increased for each 1-point increase in Neuroticism score (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.28-2.36, p<0.001). We found a positive correlation between Conscientiousness score and subjective knee scores at 3 and 6 months after surgery (p<0.001). For every 1-point increase in Conscientiousness score, the odds of a poor balance test result were decreased (OR 0.29, 95% CI 0.16-0.54, p<0.001). Agreeableness and Openness to experience scores were positively correlated with subjective knee scores at 3 and 6 months after surgery (p<0.001). We found no correlation between Extraversion and subjective knee scores at 3 and 6 months after surgery (p>0.05) but a positive correlation with the Tegner activity score at 3 and 6 months after surgery (p<0.05). CONCLUSION: We found a significant correlation between the Big Five personality dimensions and the early rehabilitation effect after ACL reconstruction, which can provide a reference for clinicians in designing a personalized rehabilitation plan.

5.
Medicine (Baltimore) ; 100(35): e27136, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477164

RESUMO

RATIONALE: Small cell neuroendocrine carcinoma of the nasal cavity and paranasal sinuses is a rare but aggressive neoplasm with a poor prognosis and a strong propensity for regional recurrence and distant metastasis. Diagnosis is challenging and relies on immunohistochemical study. Treatment includes surgical resection, radiation therapy, chemotherapy, or a combination of these modalities. However, the optimal therapeutic strategy is still controversial. Due to its rarity, the complexity of the histological diagnosis, and the variety of the treatment regimens, we presented a case of primary small cell neuroendocrine carcinoma in the nasal cavity with description of the clinical manifestation, pathology features, and our treatment regimen. PATIENT CONCERNS: An 82-year-old female patient with hypertension presented with right epistaxis on and off with nasal obstruction for several days. DIAGNOSIS: An exophytic mass over the posterior end of the right inferior turbinate was found on nasopharyngoscope. Biopsy was done and the pathology confirmed small cell carcinoma, strongly positive for cytokeratin (AE1/AE3) and insulinoma-associated protein 1 (INSM-1), scatteredly positive for chromogranin A, synaptophysin and CD56. The final diagnosis was small cell neuroendocrine carcinoma of right nasal cavity, pT1N0M0, stage I. INTERVENTIONS: The patient underwent wide excision of right intra-nasal tumor and post-operative radiotherapy with a dose of 6600 cGy in 33 fractions. OUTCOMES: No local recurrence or distant metastasis was noted during the 12 months of follow-up. LESSONS: Multimodality treatment remains the most common therapeutic strategy, although no proven algorithm has been established due to the rarity of this disease. Further investigation is needed for providing evidence to standardize the treatment protocol.


Assuntos
Carcinoma Neuroendócrino/patologia , Cavidade Nasal/patologia , Neoplasias Nasais/patologia , Idoso de 80 Anos ou mais , Carcinoma Neuroendócrino/radioterapia , Carcinoma Neuroendócrino/cirurgia , Feminino , Humanos , Neoplasias Nasais/radioterapia , Neoplasias Nasais/cirurgia
6.
Phytochemistry ; 192: 112935, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478990

RESUMO

Thirteen compounds were isolated from the lipid-soluble extracts of Illicium ternstroemioides A. C. Smith, including eleven previously undescribed prenylated C6-C3 compounds, a previously undescribed prenylated C6-C3 derivative-abscisic acid ester hybrid, and a known compound (4S)-illicinone I. Their structures and configurations were mainly elucidated by spectroscopic analyses, CD experiments and X-ray crystallography. (2S,4R,11S)-4-O-methyl-12-chloroillifunone C, (2S,4R,11R)-2,3-dihydro-4-O-methyl illioliganfunone D, and illiternfunol A were found to exhibit weak activity against Coxsackievirus B3, with IC50 values ranging from 27.8 to 33.3 µM. Illiternone B exhibited more potent activities against Coxsackievirus B3 and influenza virus A than did its geometric isomer illiternone A, with IC50 values of 7.7 µM and 2.5 µM, respectively. None of these compounds displayed cytotoxic activities.

7.
Ecotoxicol Environ Saf ; 225: 112737, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34482067

RESUMO

Zearalenone (ZEA) has an estrogenic effect and often causes reproductive damage. Pigs are particularly sensitive to it. Lycopene (LYC) is a type of fat-soluble natural carotenoid that has antioxidant, anti-inflammatory, anti-cancer, anti-cardiovascular and detoxifying effects. In this study, piglet sertoli cells (SCs) were used as research objects to investigate the mechanism of ZEA induced damage to piglet SCs and to evaluate the protective effect of LYC on ZEA induced toxic damage to piglet SCs. The results showed that ZEA damaged the cell structure and inhibited the expression of nuclear factor erythroid-2 related factor 2 (Nrf2) in the nucleus, which down-regulated the relative mRNA expression of heme oxygenase 1 (HO-1) and glutathione peroxidase 1 (GPX1) and decreased the activity of HO-1, glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD), resulting in an increase in malondialdehyde (MDA) and reactive oxygen species (ROS) content. ZEA downregulated the relative mRNA and protein expression of bcl-2 in piglet SCs, promoted cell apoptosis, and upregulated the relative mRNA and protein expression of LC3, beclin-1, and bax. After 3 h LYC-pretreatment, ZEA was added for mixed culture. The results of pretreatment with LYC showed that LYC could alleviate the cytotoxicity of ZEA to porlets SCs. Compared with ZEA group, improved the cell survival rate, promoted the expression of Nrf2 in the nucleus, upregulated the relative mRNA expression of HO-1 and GPX1, increased the activity of antioxidant enzymes, and reduced the levels of MDA and ROS. Moreover, after pretreatment with LYC, the mRNA expression of bcl-2 was upregulated, the apoptosis rate was decreased, the relative mRNA and protein expressions of LC3, beclin-1 and bax were downregulated, and autophagy was alleviated. In conclusion, LYC alleviated the oxidative damage of SCs caused by ZEA by promoting the expression of Nrf2 pathway and decreased autophagy and apoptosis.

8.
Water Res ; 204: 117628, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34507021

RESUMO

Both biological sulfate reduction process and sulfur reduction process are attractive technologies for metal-laden wastewater treatment. However, the acidity stress of metal-laden wastewater could affect the sulfidogenic performance and the microbial community, weaken the stability, efficiency and cost-effectiveness of the biological sulfidogenic processes (BSP). In this study, long-term lab-scale trials were conducted with a sulfate-reducing bioreactor and a sulfur-reducing bioreactor to evaluate the effects of acidity on sulfidogenic activities and the microbial community of the BSP. In the 300-day trial, the sulfate-reducing bacteria (SRB)-driven BSP was stable in terms of sulfidogenic performance and microbial community with the decline of pH, while the sulfur-reducing bacteria (S0RB)-driven BSP achieved high-rate and low-cost sulfide production under neutral conditions but unstable under acidic conditions. With the decline of pH, the sulfide production rate (SPR) of the SRB-driven BSP stably increased from 30 to 83 mg S/L-h; while it decreased from 56 to 37 mg S/L-h in the S0RB-driven BSP with high fluctuation. The results of estimation were consistent with the thermodynamical calculations, in which the sulfur reduction process showed a better performance at pH 5-7, while the sulfate reduction process might gain more energy when pH<5. The stable sulfidogenic performance and microbial community diversity of the SRB-driven BSP could be attributed to the alkalinity produced in sulfate reduction to buffer the acidic stress. In comparison, the microbial community in the S0RB-driven BSP was significantly re-shaped by acidity stress, and the predominant sulfidogenic bacterium changed from Desulfovibrio at neutral condition, to Desulfurella at pH≤5.4. The stability of the microbial community significantly affected the SPR and the operational cost. Nevertheless, the organic consumption for sulfide production of the S0RB-driven BSP was still less than the SRB-driven BSP even in acidic conditions. Collectively, the S0RB-driven BSP was recommended under neutral or mild acid conditions, while the SRB-driven BSP was more suitable under fluctuating pH conditions, especially at low pH. Overall, this study presented the long-term performance of SRB- and S0RB-driven BSP under varying pH conditions, and provided guidance to determine the suitable BSP and operational cost for different metal-laden wastewater.

10.
J Virol Methods ; 298: 114286, 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34520808

RESUMO

Maize lethal necrosis disease (MLND) is a serious disease of worldwide importance. It is caused by the co-infection of maize with maize chlorotic mottle virus (MCMV) and a potyvirus, such as sugarcane mosaic virus (SCMV), that acts synergistically to produce more severe symptoms and production losses. More recently, maize yellow mosaic virus (MaYMV) and maize-associated totivirus (MATV) were found to co-infect with MCMV and SCMV in maize plants. To facilitate the detection of these viruses in co-infected maize, a multiplex RT-PCR assay was developed in this study. The assay used five specific primer pairs and simultaneously amplified these four viruses as well as the elongation factor 1α (EF 1α) gene use as internal control in one tube. The concentration of the primers, annealing temperature, annealing time, extension time and amplification cycles were optimized for the multiplex RT-PCR. The detection limit of the assay was up to 100 pg of total cDNA template. This multiplex RT-PCR assay was shown to be a sensitive and effective tool for the screening of field samples for the presence of these viruses in co-infected maize.

11.
Med Sci Monit ; 27: e932404, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34493698

RESUMO

BACKGROUND Studies in ApoE knockout mice have shown that pseudolaric acid B (PB) can act as an immunomodulatory drug and attenuate atherosclerosis progression by modulating monocyte/macrophage phenotypes. Our previous study demonstrated that high salt intake could shift the phenotype of monocytes/macrophages to an inflammatory phenotype, and that this shift was related to hypertension and hypertensive left ventricular (LV) remodeling. However, no comprehensive assessment of the effects of PB on hypertensive LV remodeling has been conducted. MATERIAL AND METHODS In this study, RAW264.7 macrophages cultured with different concentrations of NaCl were used to investigate the modulating effects of PB on macrophage phenotype. Furthermore, N-nitro-L-arginine methyl ester hypertensive mice were used to investigate the modulating effects of PB on monocyte phenotype. LV remodeling was investigated by echocardiography. LV morphologic staining (for cardiomyocyte hypertrophy and collagen deposition) was performed at the time of sacrifice. RESULTS The results showed that PB significantly improved the viability of RAW264.7 cells, suppressed their phagocytic and migration abilities, and inhibited their phenotypic shift to M1 macrophages. In addition, the blood pressure of PB-treated mice was significantly decreased relative to that of control mice. Furthermore, after PB treatment, the percentage of Ly6Chi monocytes was significantly decreased while that of Ly6Clo monocytes was apparently increased. Moreover, PB preserved LV function and alleviated myocardial fibrosis and cardiomyocyte hypertrophy as measured at the end of the experimental period. The transfer of monocytes from PB-treated mice to hypertensive mice achieved the same effects. CONCLUSIONS Together, these findings indicate that PB exerts its protective effects on hypertensive LV remodeling by modulating monocyte/macrophage phenotypes and warrants further investigation.

12.
BMC Neurol ; 21(1): 336, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479481

RESUMO

BACKGROUND: Craniopharyngioma (CP) is a slow-growing, benign tumor of the central nervous system located within the sellar and suprasellar regions. The tumor may extend from the suprasellar region to other areas. CPs are generally believed to originate from squamous remnants of an incompletely involuted craniopharyngeal duct that also develops from Rathke's pouch. Primary parasellar craniopharyngioma is a relatively rare tumor, and nasal endoscopy, computed tomography, and enhanced magnetic resonance imaging can be applied to better evaluate the invasiveness and characteristics of these tumors. CASE PRESENTATION: We report a case of right parasellar craniopharyngioma in a 49-year-old female patient with a 10-day history of dizziness and blurred vision. Preoperative imaging examination revealed right parasellar space-occupying lesions, and the patient underwent transnasal neuroendoscopic resection of the right parasellar space-occupying lesion. The postoperative pathological result confirmed craniopharyngioma. CONCLUSIONS: Primary ectopic parasellar craniopharyngioma is a relatively rare tumor, and preoperative imaging examination can assist in the evaluation of tumor characteristics. However, the final diagnosis continues to depend on the histopathological results.

13.
Biomed Res Int ; 2021: 5574282, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34497850

RESUMO

Programmed cell death 1 ligand (PD-L1) and its receptor (PD-1) are key molecules for immunoregulation and immunotherapy. PD-L1 binding PD-1 is an effective way to regulate T or B cell immunity in autoimmune diseases such as rheumatoid arthritis (RA). In our study, we overexpressed PD-L1 by constructing a recombinant of PD-L1-lentiviral vector, which was subsequently used to transfect mouse bone marrow mesenchymal stem cells (MBMMSCs) and significantly suppressed the development of collagen-induced arthritis (CIA) in DBA/1j mice. In addition, PD-L1-transfected MBMMSCs (PD-L1-MBMMSCs) ameliorated joint damage, reduced proinflammatory cytokine expression, and inhibited T and B cell activation. Furthermore, PD-L1-MBMMSCs decreased the number of dendritic cells and increased the numbers of regulatory T cells and regulatory B cells in joints of CIA mice. In conclusion, our results provided a potential therapeutic strategy for RA treatment with PD-L1-MBMMSC-targeted therapy.

14.
Biol Reprod ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34467369

RESUMO

Seasonal reproduction contributes to increased chances of offspring survival in some animals. Dairy goats are seasonal breeding mammals. In this study, adult male Guanzhong dairy goats (10-12 months old) were used. Testis size, semen quality, hormone level, apoptosis of germ cells, and autophagy of Sertoli cells were analyzed in dairy goats during the breeding (October) and non-breeding (April) seasons. We found that, during the non-breeding season for dairy goats, semen quality, follicle-stimulating hormone (FSH) levels, and testosterone levels were reduced, and the number of apoptotic germ cells increased. The proliferation with decrease activity of germ cells in dairy goat during the non-breeding season was significantly affected. However, the testis size did not change seasonally. Interestingly, Sertoli cell autophagy was more active during the non-breeding season. The expression levels of FSH receptor (FSHR), wilms tumor 1 (WT1), androgen binding protein (ABP), glial cell derived neurotrophic factor (GDNF), and stem cell factor (SCF) decreased in dairy goats during the non-breeding season. In summary, our results indicate that spermatogenesis in dairy goats during the non-breeding season was not completely arrested. In addition, germ cell apoptosis and the morphology of Sertoli cells considerably changed in dairy goats during the non-breeding season. Sertoli cell autophagy is involved in the seasonal regulation of spermatogenesis in dairy goats. These findings provide key insights into the fertility and spermatogenesis of seasonal breeding animals.

15.
J Pept Sci ; : e3365, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34467600

RESUMO

Long-chain scorpion toxin AaH-II isolated from Androctonus australis Hector can selectively inhibit mammalian voltage-gated sodium ion channel Nav 1.7 responsible for pain sensation. Efficient chemical synthesis of AaH-II and its derivatives is beneficial to the study of the function and mechanism of Nav 1.7 and the development of potential peptide inhibitors. Herein, we compared three different strategies, namely, direct solid-phase peptide synthesis, hydrazide-based two-segment native chemical ligation, and hydrazide-based three-segment native chemical ligation for the synthesis of AaH-II. The hydrazide-based two-segment native chemical ligation affords the target toxin with the optimal efficiency, which provides a practically robust procedure for the preparation of tool molecules derived from AaH-II to study the biological functions and modulation of Nav 1.7. Our work highlights the importance of selecting suitable segment condensation approach in the chemical synthesis of protein toxins.

16.
PLoS Comput Biol ; 17(9): e1009376, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34491989

RESUMO

Regulatory elements control gene expression through transcription initiation (promoters) and by enhancing transcription at distant regions (enhancers). Accurate identification of regulatory elements is fundamental for annotating genomes and understanding gene expression patterns. While there are many attempts to develop computational promoter and enhancer identification methods, reliable tools to analyze long genomic sequences are still lacking. Prediction methods often perform poorly on the genome-wide scale because the number of negatives is much higher than that in the training sets. To address this issue, we propose a dynamic negative set updating scheme with a two-model approach, using one model for scanning the genome and the other one for testing candidate positions. The developed method achieves good genome-level performance and maintains robust performance when applied to other vertebrate species, without re-training. Moreover, the unannotated predicted regulatory regions made on the human genome are enriched for disease-associated variants, suggesting them to be potentially true regulatory elements rather than false positives. We validated high scoring "false positive" predictions using reporter assay and all tested candidates were successfully validated, demonstrating the ability of our method to discover novel human regulatory regions.

17.
IEEE Trans Cybern ; PP2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34543214

RESUMO

During the past two decades, many evolutionary algorithms have been proposed to solve nonlinear equation systems (NESs). However, the benchmark test sets have not received enough attention. Some features of NESs (e.g., high dimension, large search range, the connectivity of the feasible region) are rarely considered in the original benchmark test sets, which results in that they cannot represent the real-world problems well. Thus, a general toolkit is proposed to generate artificial test problems and 18 test instances with diverse characteristics are constructed in this article, which is the first attempt to design NESs. The experimental results indicate that the current algorithms perform poorly on this new benchmark test set. Furthermore, we develop a transformation method that transforms a NES into a new single-objective optimization problem and design a two-phase method to solve this transformed multimodal optimization problem. Compared to other algorithms, the proposed method has a superior or at least competitive performance.

18.
Nat Prod Res ; : 1-6, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34544305

RESUMO

Two new α-pyrones, micropyrones A (1) and B (2), along with four known γ-pyrones, nocapyrone D (3), nocapyrone A (4), marinactinone A (5), and nocapyrone H (6), were isolated from the culture extract of actinomycete Microbacterium sp. GJ312, which was isolated from Glycyrrhiza uralensis. The structures of these compounds were identified by analysis of spectral data. They are the first α- and γ-pyrones reported from the genus Microbacterium. The antibacterial activity of all compounds against Staphylococcus aureus and methicillin resistant S. aureus was evaluated. However, none of them showed significant activity. This study represents the first phytochemical example of a Glycyrrhiza-derived actinomycete.

19.
Injury ; 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34544588

RESUMO

The tourniquet or femoral artery ligation is widely used to stop extremity hemorrhage or create a bloodless operating field in the combat scenario and civilian setting. However, these procedures with subsequent reperfusion also induce ischemia-reperfusion (IR) injuries. To fully evaluate animal models of limb IR injuries, we compared tourniquet- and femoral artery ligation-induced IR injuries in the hindlimb of mice. In C57/BL6 mice, 3 h of unilateral hindlimb ischemia was induced by placement of a rubber band at the hip joint or a surgical ligation of the femoral artery. The tourniquet or femoral artery ligation was then released, allowing for 24 h of reperfusion. Compared to the femoral artery ligation/IR, the tourniquet/IR induced more severe skeletal muscle damage, including muscle necrosis and interruption of muscle fibers. There was no gastrocnemius muscle contraction in tourniquet/IR, while femoral artery ligation/IR markedly weakened gastrocnemius muscle contraction. Motor nerve terminals disappeared, and endplate potentials (EPPs) were undetectable in tourniquet/IR, whereas femoral artery ligation/IR only induced mild impairment of motor nerve terminals and decreased the amplitude of EPPs. Additionally, western blot data showed that proinflammatory cytokine levels (IL-1ß and TNF-α) were higher in the tourniquet/IR than that in femoral artery ligation/IR. Moreover, tourniquet/IR caused significant tissue edema and dilation of lymphatic vessels in the hindlimb, compared to femoral artery ligation/IR. The above data demonstrated that tourniquet/IR-induced acute hindlimb injuries are more severe than those induced by femoral artery ligation/IR. This suggests that future investigators should determine which hindlimb IR model (tourniquet/IR or femoral artery ligation/IR) is optimal depending on the purpose of their study.

20.
Bioresour Technol ; 341: 125840, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34469821

RESUMO

A novel municipal wastewater treatment process towards energy neutrality and reduced carbon emissions was established by combining a submerged anaerobic membrane bioreactor (SAnMBR) with a one-stage partial nitritation-anammox (PN/A), and was demonstrated at pilot-scale at 25 °C. The overall COD and BOD5 removal efficiencies were 95.1% and 96.4%, respectively, with 20.3 mg L-1 COD and 5.2 mg L-1 BOD5 remaining in the final effluent. The total nitrogen (TN) removal efficiency was 81.7%, resulting 7.3 mg L-1 TN was discharged from the system. The biogas yield was 0.222 NL g-1 COD removed with a methane content range of 78-81%. Approximately 90% of influent COD was removed in the SAnMBR, and 70% of influent nitrogen was removed in the PN/A. The denitrification which occurred in the PN/A enhanced overall COD and nitrogen removal. The successful operation of this pilot-scale plant indicates the SAnMBR-PN/A process is suitable for treating real municipal wastewater.

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