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1.
Bioresour Technol ; 400: 130640, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554761

RESUMO

As a byproduct of dairy production, the disposal of acid whey poses severe environmental challenges. Herein, an innovative solution involving metabolically engineering Clostridium saccharoperbutylacetonicum to convert all carbon sources in acid whey into sustainable biofuels and biochemicals was presented. By introducing several heterologous metabolic pathways relating to metabolisms of lactose, galactose, and lactate, the ultimately optimized strain, LM-09, exhibited exceptional performance by producing 15.1 g/L butanol with a yield of 0.33 g/g and a selectivity of 89.9%. Through further overexpression of alcohol acyl transferase, 2.7 g/L butyl acetate along with 6.4 g/L butanol was generated, resulting in a combined yield of 0.37 g/g. This study achieves the highest reported butanol titer and yield using acid whey as substrate in clostridia and marks pioneering production of esters using acid whey. The findings demonstrate an innovative bioprocess that enhances renewable feedstock biotransformation, thereby promoting economic viability and environmental sustainability of biomanufacturing.


Assuntos
Biocombustíveis , Clostridium , Engenharia Metabólica , Soro do Leite , Soro do Leite/metabolismo , Clostridium/metabolismo , Engenharia Metabólica/métodos , Butanóis/metabolismo , Fermentação
2.
Waste Manag ; 175: 42-51, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38159367

RESUMO

A new green pathway of in situ electro-leaching coupled with electrochemically switched ion exchange (EL-ESIX) technology was developed for the separation and recovery of valuable metal ions from waste lithium batteries. By using the in situ electro-leaching, the leaching rates of Li+ and Co2+ from the prepared LiCoO2 film electrodes reached 100 % and 93.30 %, respectively, under the combined effect of the acidic microenvironment formed by the anodic electrolytic water and electrostatic repulsion. Subsequently, the Li+ in the electrolyte was further extracted by an electrochemically switched ion exchange (ESIX) process using LiMn2O4 as the film electrode, and Li+ was further enriched in the eluate by a cyclic adsorption and desorption process. The results indicate that the in situ electro-leaching has significant advantages over powder leaching, and for the recycling of waste lithium batteries, the final lithium recovery rate reached 94.51 % by using this in situ EL-ESIX technology.


Assuntos
Lítio , Metais , Troca Iônica , Reciclagem/métodos , Fontes de Energia Elétrica , Íons , Eletrodos
3.
Int J Med Inform ; 176: 105113, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37290271

RESUMO

BACKGROUND: The COVID-19 pandemic was an international systemic crisis which required an unprecedented response to quickly drive the digital transformation of hospitals and health care systems to support high quality health care while adhering to contagion management protocols. OBJECTIVE: To identify and assess the best practices during the COVID-19 pandemic by Chief Information Officers (CIOs) about how to build resilient healthcare IT (HIT) to improve pandemic preparedness and response across global settings and to develop recommendations for future pandemics. METHODS: We conducted a qualitative, interview-based study to sample CIOs in hospitals. We interviewed 16 CIOs from hospitals and health systems in the United States and Abu Dhabi, United Arab Emirates. We used in-depth interviews to capture their perspectives of the preparedness of hospitals' information technology departments for the pandemic and how they lead their IT department out of the pandemic. RESULTS: Results showed that healthcare CIOs were ambidextrous IT leaders who built resilient HIT by rapidly improving existing digital business practices and creating innovative IT solutions. Ambidextrous IT leadership involved exploiting existing IT resources as well as exploring and innovating for continuous growth. IT resiliency focused on four inter-related capabilities: ambidextrous leadership, governance, innovation and learning, and HIT infrastructure. CONCLUSIONS: We propose conceptual frameworks to guide the development of healthcare IT resilience and highlight the importance of organizational learning as an integral component of HIT resiliency.


Assuntos
COVID-19 , Liderança , Humanos , Estados Unidos , Emirados Árabes Unidos/epidemiologia , Tecnologia da Informação , Pandemias , COVID-19/epidemiologia , Hospitais
4.
Anal Bioanal Chem ; 413(29): 7195-7204, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34697653

RESUMO

The pandemic of the novel coronavirus disease 2019 (COVID-19) has caused severe harm to the health of people all around the world. Molecular detection of the pathogen, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), played a crucial role in the control of the disease. Reverse transcription digital PCR (RT-dPCR) has been developed and used in the detection of SARS-CoV-2 RNA as an absolute quantification method. Here, an interlaboratory assessment of quantification of SARS-CoV-2 RNA was organized by the National Institute of Metrology, China (NIMC), using in vitro transcribed RNA samples, among ten laboratories on six different dPCR platforms. Copy number concentrations of three genes of SARS-CoV-2 were measured by all participants. Consistent results were obtained with dispersion within 2.2-fold and CV% below 23% among different dPCR platforms and laboratories, and Z' scores of all the reported results being satisfactory. Possible reasons for the dispersion included PCR assays, partition volume, and reverse transcription conditions. This study demonstrated the comparability and applicability of RT-dPCR method for quantification of SARS-CoV-2 RNA and showed the capability of the participating laboratories at SARS-CoV-2 test by RT-dPCR platform.


Assuntos
Laboratórios/organização & administração , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/genética , COVID-19/virologia , Humanos , Limite de Detecção
5.
J Clin Neurosci ; 91: 118-124, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34373015

RESUMO

OBJECTIVE: Papillary meningioma is rare and displays an aggressive clinical behavior with poor prognosis. Therefore, we performed an extensive literature review to evaluate the adverse factors and treatment strategy of survival. METHOD: We performed Ovid, Medline, Embase, Pubmed, Web of Science and Cochrane database queries for articles published between 1938 and 2019 with the search term "WHO grade III meningioma" or "papillary meningioma" and "central nervous system", "cerebral", or "intracranial". RESULTS: After a careful evaluation, a total of 19 studies were included. The entire cohort included the 67 patients, 34 (50.7%) were male and 33 (49.3%) were female with a mean age of 32.6 ± 2.1 years ranging from 4.5 months to 74 years. Gross total resection was achieved in 48 (71.6%) cases, and 29 (51.8%) patients received postoperative radiation. The mean follow-up period was 42.3 ± 4.4 months (range, 2-197 months). Thirty-six (53.7%) patients happened to recurrences, 11 (16.4%) patients happened to extracranial metastasis and 25 (37.3%) patients died. Univariate analysis revealed that the MIB > 5% trended toward a shorter time to recurrence (p = 0.084). Gross total resection was associated with favorable progression-free survival (p = 0.007) and overall survival (p = 0.001). Postoperative radiation was associated with favorable progression-free survival (p = 0.001). CONCLUSIONS: Gross total resection and adjuvant radiation were recommended as the initial treatment option for patients with papillary meningioma.


Assuntos
Neoplasias Meníngeas , Meningioma , Adulto , Feminino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/terapia , Meningioma/diagnóstico , Meningioma/terapia , Recidiva Local de Neoplasia , Prognóstico , Intervalo Livre de Progressão , Estudos Retrospectivos
6.
Nat Commun ; 12(1): 4368, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34272383

RESUMO

Bioproduction of renewable chemicals is considered as an urgent solution for fossil energy crisis. However, despite tremendous efforts, it is still challenging to generate microbial strains that can produce target biochemical to high levels. Here, we report an example of biosynthesis of high-value and easy-recoverable derivatives built upon natural microbial pathways, leading to improvement in bioproduction efficiency. By leveraging pathways in solventogenic clostridia for co-producing acyl-CoAs, acids and alcohols as precursors, through rational screening for host strains and enzymes, systematic metabolic engineering-including elimination of putative prophages, we develop strains that can produce 20.3 g/L butyl acetate and 1.6 g/L butyl butyrate. Techno-economic analysis results suggest the economic competitiveness of our developed bioprocess. Our principles of selecting the most appropriate host for specific bioproduction and engineering microbial chassis to produce high-value and easy-separable end products may be applicable to other bioprocesses.


Assuntos
Acetatos/metabolismo , Butiratos/química , Clostridium/metabolismo , Ácidos Graxos/metabolismo , Fermentação/genética , Engenharia Metabólica/métodos , Acetilcoenzima A/metabolismo , Biocombustíveis/microbiologia , Biomassa , Clostridium/enzimologia , Clostridium/genética , Ésteres/metabolismo , Redes e Vias Metabólicas/genética , NAD/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteínas Recombinantes
7.
Anal Methods ; 13(18): 2114-2123, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33870958

RESUMO

Circulating tumor DNA (ctDNA)-based mutation detection is promising to change the clinical practice of genotype-directed therapy for cancer. A growing number of non-invasive tests for cancer screening and monitoring that involve the detection of ctDNA have been commercialized. Primary reference measurement procedures (PRMPs) and reference materials (RMs) are urgently needed to assess the non-invasive tests. In this study, a PRMP based on digital PCR (dPCR) and ctDNA RMs for quantification of the frequently occurring variant in epidermal growth factor receptor (EGFR L858R, T790M, and 19Del) in non-small cell lung cancer (NSCLC) were established. The candidate dPCR PRMP showed high specificity (false positive rate 0-0.003%), good repeatability (coefficient of variance (CV), 2-3% for 104 copies/reaction), and high interlaboratory reproducibility (3-10%). A good linearity (0.97 < slope < 1.03, R2 ≥ 0.9999) between the measured mutant (MU) value and prepared value was observed for all assays over the fractional abundance (FA) range, between 25% and 0.05%. The limit of quantification (LoQ) was determined to be 34 L858R, 23 T790M, and 34 19Del copies/reaction, corresponding to a FA of 0.2%. An inter-laboratory study of using the EGFR ctDNA RMs and dPCR assays demonstrated that the participating laboratories produced consistent concentrations of MU and wild-type (WT), as well as FA. This study demonstrates that dPCR can act as a potential PRMP for EGFR mutation for validation of NSCLC genotyping tests and ctDNA quantitative tests. The PRMP and RMs established here could improve interlaboratory repeatability and reproducibility, which supports rapid translation and application of non-invasive tests into clinical practice.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/diagnóstico , Mutação , Inibidores de Proteínas Quinases , Reprodutibilidade dos Testes
8.
Appl Environ Microbiol ; 87(7)2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33514516

RESUMO

Biobutanol is a valuable biochemical and one of the most promising biofuels. Clostridium saccharoperbutylacetonicum N1-4 is a hyperbutanol-producing strain. However, its strong autolytic behavior leads to poor cell stability, especially during continuous fermentation, thus limiting the applicability of the strain for long-term and industrial-scale processes. In this study, we aimed to evaluate the role of autolysin genes within the C. saccharoperbutylacetonicum genome related to cell autolysis and further develop more stable strains for enhanced butanol production. First, putative autolysin-encoding genes were identified in the strain based on comparison of amino acid sequence with homologous genes in other strains. Then, by overexpressing all these putative autolysin genes individually and characterizing the corresponding recombinant strains, four key genes were pinpointed to be responsible for significant cell autolysis activities. Further, these key genes were deleted using CRISPR-Cas9. Fermentation characterization demonstrated enhanced performance of the resultant mutants. Results from this study reveal valuable insights concerning the role of autolysins for cell stability and solvent production, and they provide an essential reference for developing robust strains for enhanced biofuel and biochemical production.IMPORTANCE Severe autolytic behavior is a common issue in Clostridium and many other microorganisms. This study revealed the key genes responsible for the cell autolysis within Clostridium saccharoperbutylacetonicum, a prominent platform for biosolvent production from lignocellulosic materials. The knowledge generated in this study provides insights concerning cell autolysis in relevant microbial systems and gives essential references for enhancing strain stability through rational genome engineering.


Assuntos
Proteínas de Bactérias/genética , Biocombustíveis/microbiologia , Butanóis/metabolismo , Clostridium/genética , N-Acetil-Muramil-L-Alanina Amidase/genética , Autólise , Proteínas de Bactérias/metabolismo , Clostridium/enzimologia , Engenharia Metabólica , N-Acetil-Muramil-L-Alanina Amidase/metabolismo
9.
Talanta ; 207: 120293, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594564

RESUMO

Droplet digital PCR (ddPCR) has attracted much attention in the detection of genetic signatures of cancer present at low levels in circulating tumor DNA (ctDNA) in blood. A growing number of laboratory-developed liquid biopsy tests based on such technology have become commercially available for clinical settings. To obtain consistent and comparable results, an international standard is necessary for validation of the analytical performance. In this study, a novel and SI-traceable "ctDNA" reference material (RM) carrying BRAF V600E was prepared by gravimetrically mixing a 152 bp PCR amplicon and sonicated wild-type genomic DNA. The ddPCR performance was evaluated by analyzing serial "ctDNA" dilutions using a competitive MGB assay. The mutant frequency concordance (k) between ddPCR and the gravimetrical value was 1.03 in the range from 53.9% to 0.1%. The limit of blank (LoB), detection (LoD) and quantification (LoQ) of ddPCR assay were determined to be 0.01%, 0.02% and 0.1%, respectively. Results from the interlaboratory study, using challenging low levels of BRAF V600E ctDNA RMs, demonstrated that the participating laboratories had the appropriate technical competency to perform accurate ddPCR-based low level of ratio measurements. However, a systematic error caused by uncorrected droplet volume in Naica Crystal ddPCR platform was found by using the ctDNA RM. Between-laboratory consistency in copy number measurement was greatly improved when a correct droplet volume was applied for the ddPCR measurement by using the ctDNA RM. This confirms that the "ctDNA" RM is fit for the validation of ddPCR systems for ctDNA quantification. This would also support translation of tests for circulating tumor DNA by ddPCR into routine use.


Assuntos
DNA Tumoral Circulante/genética , Análise Mutacional de DNA/normas , Laboratórios , Reação em Cadeia da Polimerase/normas , Proteínas Proto-Oncogênicas B-raf/genética , Padrões de Referência , Incerteza
10.
Bioresour Technol ; 281: 217-225, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30822643

RESUMO

In the clostridial acetone-butanol-ethanol (ABE) fermentation, the intermediate acetate and butyrate are re-assimilated for solvent production. Here, key genes in ABE pathways in Clostridium saccharoperbutylacetonicum N1-4 were overexpressed to enhance acid re-assimilation and solvent production. With the overexpression of sol operon, acid re-assimilation was enhanced, and ABE production was increased by 20%, with ethanol production increased by six times but almost no increase in butanol production. To further drive carbon flux for C4 metabolites and ultimate butanol production, key genes including hbd, thl, crt and bcd in butanol production pathway were further overexpressed. Compared to the control, butanol, acetone and total ABE production in the new strain was increased by 8%, 18%, and 12.4%, respectively. Finally, simultaneous saccharification and fermentation was carried out using acetate-pretreated switchgrass. 15.4 g/L total ABE (with a yield of 0.31 g/g) was produced in both engineered strains, which was significantly higher than the control.


Assuntos
Biocombustíveis , Biomassa , Celulose/metabolismo , Clostridium/metabolismo , Engenharia Metabólica/métodos , Acetona/metabolismo , Butanóis/metabolismo , Etanol/metabolismo , Fermentação , Solventes/metabolismo
11.
Sci Rep ; 8(1): 9650, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30504843

RESUMO

KRAS gene mutations are predictive markers of non-response to anti-epidermal growth factor receptor. An increasing number of techniques are being developed to detect KRAS mutations. To obtain consistent and comparable results, a traceable reference material (RM) is necessary for validation the routinely used method. However, a lack of reference methods is a main impediment for deriving traceability and measurement comparability. In this study, droplet digital PCR (ddPCR) and next generation sequencing (NGS) were evaluated. No cross- reactivity was detected with any of the probe by ddPCR. The measured fraction of KRAS mutant allele by ddPCR and NGS agreed with the prepared value by gravimetrical dilution (concordance (k) >0.95 and >0.93 for ddPCR and NGS, respectively). The reliable limit of quantification (LOQ) was 0.1% and 1% for ddPCR and NGS, respectively. In conclusion, the validated ddPCR and NGS are suitable to characterize the KRAS RM due to the high specificity and accuracy. Verification of the LOD of three commercial kits by using the NIM-KRAS-8 RM showed that the LOD was inconsistent with the claimed LOD of the kits (1%) for some assays. This indicates a traceable RM was important for setting up the criteria regarding the LOD for the commercial kit.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Reação em Cadeia da Polimerase/métodos , Proteínas Proto-Oncogênicas p21(ras)/genética , Análise de Sequência de DNA/métodos , Células A549 , Alelos , Neoplasias Colorretais/diagnóstico , Confiabilidade dos Dados , Genoma Humano/genética , Células HCT116 , Células HEK293 , Homozigoto , Humanos , Limite de Detecção , Mutação , Telomerase/genética
12.
Pharmazie ; 70(3): 199-204, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25980181

RESUMO

Gracillin, a kind of steroidal saponin isolated from the root bark of wild yam Dioscorea nipponica has been reported to exert antitumor activity. In the present study, we investigated the anticancer activity of gracillin against HL60 cells, and evaluated the possible mechanism involved in its antineoplastic action. The cell proliferation was evaluated by cell counting Kit-8 (CCK-8) assay, gracillin inhibited the growth of HL60 cells in a time- and concentration-dependent manner. Flow cytometry was used to analyze the cell cycle distribution whereas Annexin V-FITC/PI flow cytometry analysis was carried out to confirm apoptosis induced by gracillin, Our results demonstrated that gracillin could induce cell cycle arrest of G1 and apoptosis in HL60 cells. Furthermore, based on the biochemical methods, induction of oxidative stress by gracillin was indicated by increased the content of malondialdehyde (MDA), and decreased superoxide dismutase (SOD) activity. In addition, real time-PCR verified the expression of apoptosis-related genes, the mRNA level of Bcl-2 was decreased dramatically, while Bax was remarkably increased by gracillin. Taken together, gracillin could induce cell cycle arrest, oxidative stress, and apoptosis in HL60 cells, and has the potential to be developed as an antitumor agent.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espirostanos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HL-60 , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
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