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1.
Enzyme Microb Technol ; 137: 109550, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32423677

RESUMO

Keratinases are promising alternatives over ordinary proteases in several industrial applications due to their unique properties compared with their counterparts in the protease categories. However, their large-scale industrial application is limited by the low expression and poor fermentation efficiency of keratinase. Here, we demonstrate that the expression level of keratinase can be improved by constructing a more efficient enzyme expression system hereby enables the highest production titer as regarding recombinant keratinase production to date. Specially, ten promoters were evaluated and the aprE promoter exhibits a significant promotion of keratinase (kerBv) titer from 165 U/mL to 2605 U/mL in Bacillus subtilis. The batch fermentation mode resulted in a maximum keratinase activity of 7176 U/mL at 36 h in a 5-L fermenter. Furthermore, the extracellular keratinase activity attained up to 16,860 U/mL via fed-batch fermentation within 30 h. The combination of keratinase with l-cysteine brings about 66.4 % degree of degradation of feather. Our work provides a new insight into the development of efficient keratinase fermentation processes with B. subtilis cell factory.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32371552

RESUMO

BACKGROUND: Colorectal cancer incidence and mortality have declined with increased screening and scientific advances in treatment. However, improvement in colorectal cancer outcomes has not been equal for all groups and disparities have persisted over time. METHODS: Data from the California Cancer Registry were used to estimate changes in 5-year colorectal cancer-specific survival over three diagnostic time periods: 1997-2002, 2003-2008, and 2009-2014. Analyses included all patients in California with colorectal cancer as a first primary malignancy. Multivariable Cox proportional hazard regression models were used to evaluate the effect of race/ethnicity, insurance status, and neighborhood socioeconomic status (nSES) on 5-year colorectal cancer-specific survival. RESULTS: On the basis of a population-based sample of 197,060 colorectal cancer cases, racial/ethnic survival disparities decreased over time among non-Hispanic Blacks (NHB) compared with non-Hispanic Whites (NHW), after adjusting for demographic, clinical, and treatment characteristics. For cases diagnosed 1997-2002, colorectal cancer-specific hazard rates were higher for NHB [HR, 1.12; 95% confidence interval (CI), 1.06-1.19] and lower for Asians/Pacific Islanders (HR, 0.92; 95% CI, 0.87-0.96) and Hispanics (HR, 0.94; 95% CI, 0.90-0.99) compared with NHW. In 2009-2014, colorectal cancer-specific HR for NHB was not significantly different to the rate observed for NHW (HR, 1.03; 95% CI, 0.97-1.10). There were no changes in disparities in nSES, but increasing disparities by health insurance status. CONCLUSIONS: We found a decrease in survival disparities over time by race/ethnicity, but a persistence of disparities by neighborhood socioeconomic status and health insurance status. IMPACT: Further investigation into the drivers for these disparities can help direct policy and practice toward health equity for all groups.

3.
Int J Oncol ; 56(5): 1115-1128, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32319588

RESUMO

DJ­1, an oncogene, has been reported to be an independent prognostic indicator of poor survival in patients with esophageal squamous cell carcinoma (ESCC). The aim of the present study was to investigate the role of DJ­1 in tumor cell proliferation and invasion in ESCC and its underlying mechanisms. It was observed that the expression level of DJ­1 was upregulated and positively associated with EMT biomarkers in 84 human ESCC tissue specimens. Overexpression and knockdown experiments demonstrated that DJ­1 was involved in proliferation, migration, invasion and EMT in ECA­109 cells in vitro and extensive peritoneal seeding in a peritoneal dissemination mice model. Furthermore, the present data revealed that DJ­1 could activate the Wnt/ß­catenin signaling pathway, which mediates the EMT and metastasis in ESCC. In conclusions, DJ­1 promoted proliferation, invasion, metastasis and the EMT in ESCC via activation of the Wnt/ß­catenin signal pathway. The present results suggested DJ­1 could represent a promising therapeutic target for the prevention and treatment of ESCC­related metastasis.

4.
Forensic Sci Int ; 311: 110293, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32320934

RESUMO

Death by mechanical asphyxia is one of the most difficult conclusions to make in forensic science, especially in corpses displaying slight or no trauma to the surface of the body. Therefore, death by mechanical asphyxia is difficult to prove in medico-legal practice. MicroRNAs (miRNAs) are a class of small, non-coding RNAs involved in the regulation of numerous physiological and pathological cellular processes. In the present study, we demonstrate that significantly increased expression of miR-3185 in cardiac tissues was detected among cases of mechanical asphyxia compared to case of craniocerebral injury, hemorrhagic shock, sudden cardiac death and poisoning. We observed no correlation between the expression of miR-3185 and postmortem interval, age or temperature. Further work indicated that CYP4A11 is a putative target gene of miR-3185 and expressed at a relatively low level in cardiac tissue specimens from cases of mechanical asphyxia compared with specimens from cases of craniocerebral injury, hemorrhagic shock, sudden cardiac death and poisoning. Our results suggest that the miRNA-3185/CYP4A11 axis is associated with mechanical asphyxia-induced death and may provide new insight into asphyxial death investigations.

5.
Bioorg Chem ; 99: 103816, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32305693

RESUMO

Three previously undescribed compounds, including a meroterpenoid, guignardone T (1), and two ophiobolin-type sesterterpenoids, maydispenoids A and B (2 and 3), along with four known compounds (4-7), were isolated from the phytopathogenic fungus Bipolaris maydis collected from Anoectochilus roxburghii (Wall.) Lindl leaves. The structures of all undescribed compounds were elucidated by spectroscopic analysis, electronic circular dichroism (ECD) calculations and single-crystal X-ray diffraction. Structurally, maydispenoids A was characterized by a fascinating decahydro-3-oxacycloocta[cd]pentalene fragment. It is notable that the compounds 2 and 3 exhibited potential inhibitory activity in anti-CD3/anti-CD28 monoclonal antibodies (mAbs) stimulated murine splenocytes proliferation, with IC50 values of 5.28 and 9.38 µM, respectively, and also suppress the murine splenocytes proliferation activated by lipopolysaccharide (LPS), with IC50 values of 7.25 and 16.82 µM, respectively. This is the first report of ophiobolin-type sesterterpenoids as immunosuppressor, and may provide new chemical templates for the development of new immunosuppressive drugs for autoimmune disease treatment.

6.
Phys Med Biol ; 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32235062

RESUMO

In this work, we explore deep learning based techniques using the information from mean detector response functions as a new method to estimate gamma ray interaction location in monolithic scintillation crystal detectors. Compared with searching based methods, deep learning techniques do not require recording all the MDRF information once the prediction networks are trained, which means the memory cost could be significantly reduced. In addition, the event positioning process using deep learning techniques only requires running through the network once, without the need to do searching in the reference dataset. This could greatly speed up the positioning process for each event. We have designed and trained four different neural networks to estimate the gamma ray interaction location given the MDRF data. We have studied network structures consisting only of fully connected (FC) layers, as well as convolutional neural networks (CNNs). In addition, we tried to use both regression and classification to generate the final prediction of the gamma ray interaction position. We evaluated the estimation accuracy, testing speed and memory cost (numbers of parameters) of different network architectures, and also compared them with the exhaustive search method. Our results indicate that deep learning based estimation methods with a well designed network structure can achieve a relative positioning error with respect to the ground truth determined by the exhaustive search method of below 1mm in both x and y directions (depth information is not considered in this work), which would imply a very high performance positioning algorithm for practical monolithic scintillation crystal detectors. The deep learning network also achieves a testing speed that is more than 400 times faster than the exhaustive search method. With proper design of the network structure, the deep learning based positioning methods have the potential to save memory cost by a factor of up to 100.

7.
Arch Argent Pediatr ; 118(2): e148, 2020 04.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32199054

RESUMO

Chronic kidney disease (CKD) is rapidly becoming the 5th most common cause of years of life lost globally by 2040. Crucially, the onset and progression of CKD is often preventable. The World Kidney Day 2020 campaign highlights the importance of preventive interventions on CKD. Primary prevention should focus on risks modification as well as reduced exposure to environmental risk factors and nephrotoxins. Blood pressure optimization and glycemic control should be one of the main interventions in persons with pre-existing kidney disease. Management of co-morbidities such as uremia and cardiovascular disease is highly recommended to avoid or delay dialysis or kidney transplantation. Globally, specific policies directed toward education and awareness about CKD screening, management and treatment are often lacking. Hence, there is an urgent need to increase the awareness of the importance of preventive measures throughout populations, professionals and policy makers around the world.

8.
Fitoterapia ; 143: 104532, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32151636

RESUMO

Six new compounds, including two new isochromane lactones, versicoisochromanes A and B (1 and 2), two new benzolactones, versicobenzos A and B (3 and 4), one furancarboxylic derivate, asperfuran A (6) and one ergosterol-type steroid, asperergoster A (7), along with five known steroids (8-12), were isolated from the Anoectochilus roxburghii endophytic fungus Aspergillus versicolor. The structures of these new compounds were determined by extensive spectroscopic techniques and electronic circular dichroism (ECD) calculations. It is notable that the new compound 7 exhibited obvious IL-1ß, NO and TNF-α inhibitory activity in LPS-stimulated RAW264.7 macrophages, with IC50 values of 35.5, 33.9 and 31.3 µM, respectively. Furthermore, compounds 7 and 8 displayed potential inhibitory effects on murine splenocytes proliferation stimulated by anti-CD3/anti-CD28 monoclonal antibodies (mAbs), meanwhile suppress the lipopolysaccharide (LPS) irritated murine splenocytes proliferation.

9.
Adv Mater ; 32(19): e1907879, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32176409

RESUMO

The commercialization of fuel cells, such as proton exchange membrane fuel cells and direct methanol/formic acid fuel cells, is hampered by their poor stability, high cost, fuel crossover, and the sluggish kinetics of platinum (Pt) and Pt-based electrocatalysts for both the cathodic oxygen reduction reaction (ORR) and the anodic hydrogen oxidation reaction (HOR) or small molecule oxidation reaction (SMOR). Thus far, the exploitation of active and stable electrocatalysts has been the most promising strategy to improve the performance of fuel cells. Accordingly, increasing attention is being devoted to modulating the surface/interface electronic structure of electrocatalysts and optimizing the adsorption energy of intermediate species by defect engineering to enhance their catalytic performance. Defect engineering is introduced in terms of defect definition, classification, characterization, construction, and understanding. Subsequently, the latest advances in defective electrocatalysts for ORR and HOR/SMOR in fuel cells are scientifically and systematically summarized. Furthermore, the structure-activity relationships between defect engineering and electrocatalytic ability are further illustrated by coupling experimental results and theoretical calculations. With a deeper understanding of these complex relationships, the integration of defective electrocatalysts into single fuel-cell systems is also discussed. Finally, the potential challenges and prospects of defective electrocatalysts are further proposed, covering controllable preparation, in situ characterization, and commercial applications.

10.
Biomark Med ; 14(6): 421-432, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32175764

RESUMO

Aim: Gastric cancer (GC) is one of the most common malignant tumors in the world. It is important to find accurate and reliable biomarkers in order to decrease whole morbidity and mortality. Results: We examined the expression of COX-2 and mTOR on GC tissue microarrays by immunohistochemistry. Multivariate COX regression analysis showed that the expression of COX-2 or mTOR was an independent factor in the prognosis of GC patients. In addition, COX-2 and mTOR have a potentially synergistic effect on predicting the prognosis of GC. Conclusion: The combined expression of COX-2 and mTOR could serve as efficient prognostic indicators and COX-2 could suppress GC metastasis via regulating mTOR.

11.
Iran J Kidney Dis ; 14(2): 69-80, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32165591

RESUMO

The global burden of chronic kidney disease (CKD) is rapidly increasing with a projection of becoming the 5th most common cause of years of life lost globally by 2040. Aggravatingly, CKD is a major cause of catastrophic health expenditure. The costs of dialysis and transplantation consume up to 3% of the annual healthcare budget in high-income countries. Crucially, however, the onset and progression of CKD is often preventable. In 2020, the World Kidney Day campaign highlights the importance of preventive interventions - be it primary, secondary, or tertiary. This complementing article focuses on outlining and analyzing measures that can be implemented in every country to promote and advance CKD prevention. Primary prevention of kidney disease should focus on the modification of risk factors and addressing structural abnormalities of the kidney and urinary tracts, as well as exposure to environmental risk factors and nephrotoxins. In persons with pre-existing kidney disease, secondary prevention; including blood pressure optimization and glycemic control, should be the main goal of education and clinical interventions. In patients with advanced CKD, management of co-morbidities such as uremia and cardiovascular disease is a highly recommended preventative intervention to avoid or delay dialysis or kidney transplantation. Political efforts are needed to proliferate the preventive approach. While national policies and strategies for non-communicable diseases might be present in a country, specific policies directed toward education and awareness about CKD screening, management and treatment are often lacking. Hence, there is an urgent need to increase the awareness of the importance of preventive measures throughout populations, professionals and policy makers.

12.
Chem Commun (Camb) ; 56(15): 2364, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32031558

RESUMO

Correction for 'Transition metal substituted sandwich-type polyoxometalates with a strong metal-C (imidazole) bond as anticancer agents' by Hongxia Zhao et al., Chem. Commun., 2019, 55, 1096-1099.

13.
Emerg Microbes Infect ; 9(1): 413-426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32079510

RESUMO

Candida albicans is a major human fungal pathogen, capable of switching among a range of morphological types, such as the yeast form, including white and opaque cell types and the GUT (gastrointestinally induced transition) cell type, the filamentous form, including hyphal and pseudohyphal cell types, and chlamydospores. This ability is associated with its commensal and pathogenic life styles. In response to pheromone, C. albicans cells are able to form long mating projections resembling filaments. This filamentous morphology is required for efficient sexual mating. In the current study, we report the genetic regulatory mechanisms controlling the development of mating projections in C. albicans. Ectopic expression of MTLα1 in "a" cells induces the secretion of α-pheromone and promotes the development of mating projections. Using this inducible system, we reveal that members of the pheromone-sensing pathway (including the pheromone receptor), the Ste11-Hst7-Cek1/2 mediated MAPK signalling cascade, and the RAM pathway are essential for the development of mating projections. However, the cAMP/PKA signalling pathway and a number of key regulators of filamentous growth such as Hgc1, Efg1, Flo8, Tec1, Ume6, and Rfg1 are not required for mating projection formation. Therefore, despite the phenotypic similarities between filaments and mating projections in C. albicans, distinct mechanisms are involved in the regulation of these two morphologies.


Assuntos
Candida albicans/genética , Proteínas Fúngicas/genética , Genes Fúngicos Tipo Acasalamento , Feromônios , Regulação Fúngica da Expressão Gênica , Hifas , Sistema de Sinalização das MAP Quinases
14.
Biomed Pharmacother ; 125: 109962, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32106373

RESUMO

Chemoresistance is still a major obstacle for lung cancer treatment. Increasing studies have demonstrated that microRNAs (miRNAs) are essential meditators of chemoresistance during cancer progression. MiR-451a is reported to be a tumor suppressor during cancer development. However, its effects on lung cancer and drug resistance in lung cancer are still unclear. In the study, the results showed that miR-451a exhibited a significant role in suppressing the drug resistance in lung cancer cells when treated with doxorubicin (DOX) through alleviating epithelialmesenchymal transition (EMT), as evidenced by the markedly reduced expression of N-cadherin and Vimentin, while the enhanced expression of E-cadherin. In addition, miR-451a over-expression markedly promoted the sensitivity of lung cancer cells to DOX treatments, and also disrupted the EMT of lung cancer cells. Mechanistically, miR-451a was found to directly target c-Myc to affect the EMT and drug resistance in lung cancer cells in response to DOX incubation. Furthermore, c-Myc knockdown markedly elevated the sensitivity of lung cancer cells to DOX, whereas over-expressing c-Myc markedly reversed the anti-tumor role of DOX, which was slightly diminished by miR-451a mimic. The in vivo experiments confirmed that miR-451a promoted the sensitivity of lung cancer cells-derived tumors to DOX treatment by reducing c-Myc. Therefore, our results revealed a new insight into DOX resistance of lung cancer cells and miR-451a could be considered as a potential therapeutic target to overcome drug resistance in lung cancer.

16.
Adv Mater ; 32(7): e1905923, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31930593

RESUMO

The reasonable design of electrode materials for rechargeable batteries plays an important role in promoting the development of renewable energy technology. With the in-depth understanding of the mechanisms underlying electrode reactions and the rapid development of advanced technology, the performance of batteries has significantly been optimized through the introduction of defect engineering on electrode materials. A large number of coordination unsaturated sites can be exposed by defect construction in electrode materials, which play a crucial role in electrochemical reactions. Herein, recent advances regarding defect engineering in electrode materials for rechargeable batteries are systematically summarized, with a special focus on the application of metal-ion batteries, lithium-sulfur batteries, and metal-air batteries. The defects can not only effectively promote ion diffusion and charge transfer but also provide more storage/adsorption/active sites for guest ions and intermediate species, thus improving the performance of batteries. Moreover, the existing challenges and future development prospects are forecast, and the electrode materials are further optimized through defect engineering to promote the development of the battery industry.

17.
J Pharm Sci ; 109(2): 1050-1058, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31622601

RESUMO

The effect of vapor sorption on the free volume of drug-polymer spray-dried dispersions (SDDs) was investigated, along with the crystallization propensity of drug molecules in SDDs after exposure to humidity. Subsequently, the correlation of free volume change and relaxation time with drug recrystallization was examined. Four polymers, including polyvinylpyrrolidone, polyvinylpyrrolidone vinyl acetate copolymer, hydroxypropyl cellulose, and hydroxypropyl methylcellulose acetate succinate, and 2 drugs (indomethacin and ketoconazole) were selected for preparing SDDs. Free volume data of the exposed SDDs were obtained with positron annihilation lifetime spectroscopy, while the relaxation time was measured using a TA rheometer. Additionally, the crystallization propensity of active pharmaceutical ingredients (APIs) in the exposed SDDs was assessed using both polarized light microscopy and powder X-ray diffraction, followed by relating API crystallization inclination with expansion of holes and relaxation time. Finally, Cohen and Turnbull molecular transport model, along with its extensions by Vrentas and Duda, was qualitatively utilized for interpreting the recrystallization propensity of API molecules. In conclusion, API recrystallization is closely related to free volume change upon moisture sorption and relaxation time, but system dependent; overall, drug-hydroxypropyl methylcellulose acetate succinate SDDs appear physically stable against recrystallization due to less increase in free volume.

18.
J Pharm Sci ; 109(1): 422-428, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31469998

RESUMO

Isomerization of surface-exposed aspartic acid (Asp) in the complementarity-determining regions of therapeutic proteins could potentially impact their target binding affinity because of the sensitive location, and often requires complex analytical tactics to understand its effect on structure-function and stability. Inaccurate quantitation of Asp-isomerized variants, especially the succinimide intermediate, presents major challenge in understanding Asp degradation kinetics, its stability, and consequently establishing a robust control strategy. As a practical solution to this problem, a comprehensive analytical tool kit has been developed, which provides a solution to fully characterize and accurately quantify the Asp-related product variants. The toolkit offers a combination of 2 steps, an ion-exchange chromatography method to separate and enrich the isomerized variants in the folded structure for structure-function evaluation and a novel focused peptide mapping method to quantify the individual complementarity-determining region isomerization components including the unmodified Asp, succinimide, and isoaspartate. This novel procedure allowed an accurate quantification of each Asp-related variant and a comprehensive assessment of the functional impact of Asp isomerization, which ultimately helped to establish an appropriate control strategy for this critical quality attribute.

19.
Int J Surg Pathol ; 28(2): 200-205, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31526158

RESUMO

Dedifferentiated liposarcoma rarely occurs in the esophagus. It always has atypical clinical manifestations and different pathologic features, which usually lead to misdiagnosis and mistreatment. Given its poor prognosis, early and accurate diagnosis is of the utmost importance. The accumulation of similar cases is critical for surgeons and pathologists to raise awareness of such tumors. This report aims to discuss the diagnosis and provide a reference for the clinical diagnosis and treatment for pathologists and clinicians.

20.
Pharm Biol ; 58(1): 16-24, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31854225

RESUMO

Context: XingNaoJing injection (XNJ), extracted from a traditional compound Chinese medicine Angong niuhuang pill, is well known for treating stroke in the clinic, but the specific effects and mechanisms remain unclear.Objective: We investigated the mechanistic basis for the protective effect of XNJ on cerebral ischaemia/reperfusion (I/R) injury.Materials and methods: Five groups of 10 SD rats underwent 2 h of middle cerebral artery occlusion (MCAO) followed by 24 h reperfusion. XNJ at 10 and 15 mL/kg was intraperitoneally administered 24 h before ischaemia and at the onset of reperfusion respectively. The silent information regulator 1 (SIRT1) inhibitor EX527 was intracerebroventricularly injected 0.5 h before reperfusion. Cerebral infarction size, neurological scores, morphological changes, and expression levels of inflammatory mediators and SIRT1 were measured. Furthermore, human brain microvascular endothelial cells (HBMECs) were subjected to 3 h oxygen and glucose deprivation (OGD) followed by 24 h reoxygenation to mimic cerebral I/R in vitro. EX527 pre-treatment occurred 1 h before OGD. SIRT1 and inflammatory mediator levels were analyzed.Results: Both XNJ doses significantly decreased cerebral infarct area (40.11% vs. 19.66% and 9.87%) and improved neurological scores and morphological changes. Inflammatory mediator levels were remarkably decreased in both model systems after XNJ treatment. XNJ also enhanced SIRT1 expression. Notably, the SIRT1 inhibitor EX527 attenuated the XNJ-mediated decrease in inflammation in vivo and in vitro.Conclusions: XNJ improved cerebral I/R injury through inhibiting the inflammatory response via the SIRT1 pathway, which may be a useful target in treating cerebral I/R injury.

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