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1.
Eur J Haematol ; 110(6): 706-714, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36941225

RESUMO

BACKGROUND: Pancreatic cancer (PC) carries a high risk of venous thromboembolism (VTE). Several risk assessment models (RAMs) predict benefit of thromboprophylaxis in solid tumors; however, none are verified in metastatic pancreatic cancer (mPC). METHODS: A retrospective mPC cohort treated at an academic cancer center from 2010 to 2016 was investigated for VTE incidence (VTEmets). Multivariable regression analysis was used to assess multiple VTE risk factors. Overall survival (OS) was compared between mPC groups with and without VTE. Survival was analyzed using Kaplan-Meier survival plots and Cox proportional hazards regressions. RESULTS: 400 mPC patients (median age 66; 52% males) were included. 87% had performance status of ECOG 0-1; 70% had advanced stage at PC diagnosis. Incidence of VTEmets was 17.5%; median time of occurrence 3.48 months after mPC diagnosis. Survival analysis started at median VTE occurrence. Median OS was 10.5 months in VTEmets vs. 13.4 in non-VTE group. Only advanced stage (OR 3.7, p = .001) correlated with increased VTE risk. CONCLUSIONS: The results suggest mPC carries a significant VTE burden. VTE predicts poor outcomes from the point of median VTE occurrence. Advanced stage disease is the strongest risk factor. Future studies are needed to define risk stratification, survival benefit, and choice of thromboprophylaxis.


Assuntos
Neoplasias Pancreáticas , Tromboembolia Venosa , Masculino , Feminino , Humanos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Anticoagulantes/efeitos adversos , Estudos Retrospectivos , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/epidemiologia , Fatores de Risco , Incidência , Neoplasias Pancreáticas
2.
Appl Environ Microbiol ; 88(13): e0075422, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35703553

RESUMO

Methyltransferases transfer a methyl group to a diverse group of natural products, thus providing structural diversity, stability, and altered pharmacological properties to the molecules. A limited number of regiospecific sugar-O-methyltransferases are functionally characterized. Thus, discovery of such an enzyme could solve the difficulties of biological production of methoxy derivatives of glycosylated molecules. In the current study, a regiospecific sugar-O-methyltransferase, ThnM1, belonging to the biosynthetic gene cluster (BGC) of 1-(α-L-(2-O-methyl)-6-deoxymannopyranosyloxy)-3,6,8-trimethoxynaphthalene produced by Nocardia sp. strain CS682, was analyzed and functionally characterized. ThnM1 demonstrated promiscuity to diverse chemical structures such as rhamnose-containing anthraquinones and flavonoids with regiospecific methylation at the 2'-hydroxyl group of the sugar moiety. Compared with other compounds, anthraquinone rhamnosides were found to be the preferred substrates for methylation. Thus, the enzyme was further employed for whole-cell biotransformation using engineered Escherichia coli to produce a methoxy-rhamnosyl derivative of quinizarin, an anthraquinone derivative. The structure of the newly generated derivative from Escherichia coli fermentation was elucidated by liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopic analyses and identified as quinizarin-4-O-α-l-2-O-methylrhamnoside (QRM). Further, the biological impact of methylation was studied by comparing the cytotoxicity of QRM with that of quinizarin against the U87MG, SNU-1, and A375SM cancer cell lines. IMPORTANCE ThnM1 is a putative sugar-O-methyltransferase produced by the Nocardia sp. strain CS682 and is encoded by a gene belonging to the biosynthetic gene cluster (BGC) of 1-(α-l-(2-O-methyl)-6-deoxymannopyranosyloxy)-3,6,8-trimethoxynaphthalene. We demonstrated that ThnM1 is a promiscuous enzyme with regiospecific activity at the 2'-OH of rhamnose. As regiospecific methylation of sugars by chemical synthesis is a challenging step, ThnM1 may fill the gap in the potential diversification of natural products by methylating the rhamnose moiety attached to them.


Assuntos
Produtos Biológicos , Nocardia , Produtos Biológicos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Metiltransferases/metabolismo , Nocardia/genética , Nocardia/metabolismo , Ramnose/metabolismo , Açúcares/metabolismo
3.
Infection ; 50(5): 1053-1066, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35489015

RESUMO

PURPOSE: Apart from the global disease burden of acute COVID-19 disease, the health complications arising after recovery have been recognized as a long-COVID or post-COVID-19 syndrome. Evidences of long-COVID symptoms involving various organ systems are rapidly growing in literature. The objective was to perform a rapid review and evidence mapping of systemic complications and symptoms of long-COVID and underlying pathophysiological mechanisms. METHODS: Publications reporting clinical trials, observational cohort studies, case-control studies, case-series, meta-analysis, and systematic reviews, focusing on the squeal of the disease, consequences of COVID-19 treatment/hospitalization, long-COVID, chronic COVID syndrome, and post acute COVID-19 were reviewed in detail for the narrative synthesis of frequency, duration, risk factors, and pathophysiology. RESULTS: The review highlights that pulmonary, neuro-psychological, and cardiovascular complications are major findings in most epidemiological studies. However, dysfunctional gastrointestinal, endocrine, and metabolic health are recent findings for which underlying pathophysiological mechanisms are poorly understood. Analysis of the clinical trial landscape suggests that more than 50% of the industry-sponsored trials are focused on pulmonary symptoms. In contrast to the epidemiological trends and academic trials, cardiovascular complications are not a focus of industry-sponsored trials, suggestive of the gaps in the research efforts. CONCLUSION: The gap in epidemiological trends and academic trials, particularly concerning cardiovascular complications not being a focus of industry-sponsored trials is suggestive of the gaps in research efforts and longer follow-up durations would help identify other long-COVID-related health issues such as reproductive health and fertility.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , COVID-19/complicações , COVID-19/epidemiologia , Hospitalização , Humanos , Fatores de Risco , Síndrome de COVID-19 Pós-Aguda
4.
Biotechnol Appl Biochem ; 69(4): 1723-1732, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34415071

RESUMO

Epothilone A, a microtubule-stabilizing agent used as therapeutics for the treatment of cancers, was biotransformed into three metabolites using Nocardia sp. CS692 and recombinant Nocardia overexpressing a cytochrome P450 from Streptomyces venezuelae (PikC). Among three metabolites produced in the biotransformation reaction mixtures, ESI/MS2 analysis predicted two metabolites (M1 and M2) as novel hydroxylated derivatives (M1 is hydroxylated at the C-8 position and M2 is hydroxylated at C-10 position), each with an opened-epoxide ring in their structure. Interestingly, metabolite M3 lacks an epoxide ring and is known as deoxyepothilone A, which is also called epothilone C. Metabolite M1 was produced only in PikC overexpressing strain. The endogenous enzymes of Nocardia sp. catalyzed hydroxylation of epothilone A to produce metabolite M2 and removed epoxide ring to produce metabolite M3. All the metabolites were identified based on UV-vis analysis and rigorous ESI/MS2 fragmentation based on epothilone A standard. The newly produced metabolites are anticipated to display novel cytotoxic effects and could be subjects of further pharmacological studies.


Assuntos
Nocardia , Biotransformação , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Epotilonas , Compostos de Epóxi , Humanos , Nocardia/genética , Nocardia/metabolismo
5.
Med J Armed Forces India ; 78(Suppl 1): S289-S292, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36147421

RESUMO

A bezoar is a mass of indigestible foreign material found in the gastrointestinal tract, usually in the stomach. Trichobezoars are the second most common bezoars which are usually found in young psychiatric patients. A 15-year-old female patient presented with signs of intestinal obstruction and acute abdomen. The preoperative investigations revealed a perforated appendix, and an exploratory laparotomy was performed. Intraoperative findings showed presence of a mass of hair in the stomach along with a long tail extending into the small intestine. Postoperatively, the patient's condition worsened and she died because of complications of perforation peritonitis on day 3. Early diagnosis of Rapunzel syndrome can help in making early interventions. The prognosis of incidental detection of this condition depends on the accompanying cause.

6.
Rheumatol Int ; 40(3): 393-397, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31773392

RESUMO

Systemic lupus erythematosus (SLE) is a multisystem disorder. While several studies have outlined risk factors for hospitalization and mortality in SLE; the frequency of hospitalizations from various causes has varied among studies and over the years. We aimed to assess the causes of SLE hospitalizations and inpatient mortality compared to those without SLE in the United States in a recent year (2016) using a large national inpatient database. We used National Inpatient Sample (NIS) to identify hospitalizations with SLE using the ICD-10 code M32. Among hospitalizations with SLE as secondary diagnosis, we used ICD-10 codes to assess the primary diagnoses associated with hospitalizations and mortality. Our study included 174,105 SLE hospitalizations matched to controls (similar age, sex, and NIS stratum) in the year 2016. Mean age of hospitalization with SLE was 51.82 years, and 89% of hospitalized SLE patients were females. Mean length of stay, cost and mortality for SLE were 5.6 ± 7.2 days, US $ 14,450 and 1.96%, respectively. SLE was the primary diagnosis in 10,185 (5.85%) of all SLE related hospitalizations. Among SLE hospitalizations, infection was the most common primary diagnosis (15.80%) followed by cardiac and renal manifestations (7.03% and 4.91% respectively). Infection was the leading cause of mortality (38.18%) followed by cardiac manifestations (12.04%). Infections and cardiac involvement were the leading causes of hospitalizations and in-hospital mortality in SLE. Whether this is related to the disease itself, its associated comorbidities or immunosuppressive agents would require further studies.


Assuntos
Hospitalização , Lúpus Eritematoso Sistêmico/mortalidade , Bases de Dados Factuais , Feminino , Mortalidade Hospitalar , Humanos , Pacientes Internados , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Estados Unidos
7.
J Ind Microbiol Biotechnol ; 47(6-7): 537-542, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32588231

RESUMO

Alizarin has been reported to have an antigenotoxic activity along with an inhibitory effect on the tumor cell growth of human colon carcinoma cells. Alizarin was biotransformed into an O-methoxide derivative using O-methyltransferase from Streptomyces avermitilis MA4680 (SaOMT2) to enhance its bioefficacy. The biotransformed product was extracted, purified, and characterized using various chromatographic and spectroscopic analyses, and confirmed to be an alizarin 2-O-methoxide. The antiproliferative activity of the compound against gastric cancer cells (AGS), uterine cervical cancer (Hela), liver cancer (HepG2), and normal cell lines was investigated. Alizarin 2-O-methoxide showed an inhibitory effect on all three cancer-cell lines at very low concentrations, from 0.078 µM, with no cytotoxicity against 267B1 (human prostate epithelial) and MRC-5 (normal human fetal lung fibroblast).


Assuntos
Antraquinonas/metabolismo , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias/patologia , Streptomyces/enzimologia , Biotransformação , Linhagem Celular Tumoral , Escherichia coli , Células HeLa , Células Hep G2 , Humanos , Microbiologia Industrial , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Neoplasias/tratamento farmacológico
8.
Microb Cell Fact ; 18(1): 137, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409353

RESUMO

Actinobacteria are characterized as the most prominent producer of natural products (NPs) with pharmaceutical importance. The production of NPs from these actinobacteria is associated with particular biosynthetic gene clusters (BGCs) in these microorganisms. The majority of these BGCs include polyketide synthase (PKS) or non-ribosomal peptide synthase (NRPS) or a combination of both PKS and NRPS. Macrolides compounds contain a core macro-lactone ring (aglycone) decorated with diverse functional groups in their chemical structures. The aglycon is generated by megaenzyme polyketide synthases (PKSs) from diverse acyl-CoA as precursor substrates. Further, post-PKS enzymes are responsible for allocating the structural diversity and functional characteristics for their biological activities. Macrolides are biologically important for their uses in therapeutics as antibiotics, anti-tumor agents, immunosuppressants, anti-parasites and many more. Thus, precise genetic/metabolic engineering of actinobacteria along with the application of various chemical/biological approaches have made it plausible for production of macrolides in industrial scale or generation of their novel derivatives with more effective biological properties. In this review, we have discussed versatile approaches for generating a wide range of macrolide structures by engineering the PKS and post-PKS cascades at either enzyme or cellular level in actinobacteria species, either the native or heterologous producer strains.


Assuntos
Actinobacteria/enzimologia , Actinobacteria/genética , Macrolídeos/metabolismo , Policetídeos/metabolismo , Produtos Biológicos/metabolismo , Engenharia Genética , Família Multigênica , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo
9.
Microb Cell Fact ; 18(1): 7, 2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30654816

RESUMO

BACKGROUND: Multi-monocistronic and multi-variate vectors were designed, built, and tested for the improved production of cyanidin 3-O-glucoside (C3G) in Escherichia coli BL21 (DE3). The synthetic bio-parts were designed in such a way that multiple genes can be assembled using the bio-brick system, and expressed under different promoters in a single vector. The vectors harbor compatible cloning sites, so that the genes can be shuffled from one vector to another in a single step, and assembled into a single vector. The two required genes: anthocyanidin synthase (PhANS) from Petunia hybrida, and cyanidin 3-O-glucosyltransferase (At3GT) from Arabidopsis thaliana, were individually cloned under PT7, Ptrc, and PlacUV5 promoters. Both PhANS and At3GT were shuffled back and forth, so as to generate a combinatorial system for C3G production. The constructed systems were further coupled with the genes for UDP-D-glucose synthesis, all cloned in a multi-monocistronic fashion under PT7. Finally, the production of C3G was checked and confirmed using the modified M9 media, and analyzed through various chromatography and spectrometric analyses. RESULTS: The engineered strains endowed with newly generated vectors and the genes for C3G biosynthesis and UDP-D-glucose synthesis were fed with 2 mM (+)-catechin and D-glucose for the production of cyanidin, and its subsequent conversion to C3G. One of the engineered strains harboring At3GT and PhANS under Ptrc promoter and UDP-D-glucose biosynthesis genes under PT7 promoter led to the production of ~ 439 mg/L of C3G within 36 h of incubation, when the system was exogenously fed with 5% (w/v) D-glucose. This system did not require exogenous supplementation of UDP-D-glucose. CONCLUSION: A synthetic vector system using different promoters has been developed and used for the synthesis of C3G in E. coli BL21 (DE3) by directing the metabolic flux towards the UDP-D-glucose. This system has the potential of generating better strains for the synthesis of valuable natural products.


Assuntos
Antocianinas/biossíntese , Escherichia coli/metabolismo , Glucosídeos/biossíntese , Antocianinas/análise , Reatores Biológicos , Catequina/metabolismo , Cromatografia Líquida de Alta Pressão , Glucose/metabolismo , Glucosídeos/análise , Glucosiltransferases/genética , Engenharia Metabólica , Oxigenases/genética , Proteínas de Plantas/genética , Plasmídeos/genética , Plasmídeos/metabolismo
10.
Appl Microbiol Biotechnol ; 103(7): 2959-2972, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30798357

RESUMO

Resveratrol (3,5,4'-trihydroxystilbene) and piceatannol (3,5,3',4'-tetrahydroxystilbene) are well-known natural products that are produced by plants. They are important ingredients in pharmaceutical industries and nutritional supplements. They display a wide spectrum of biological activity. Thus, the needs for these compounds are increasing. The natural products have been found in diverse plants, mostly such as grapes, passion fruit, white tea, berries, and many more. The extraction of these products from plants is quite impractical because of the low production in plants, downstream processing difficulties, chemical hazards, and environmental issues. Thus, alternative production in microbial hosts has been devised with combinatorial biosynthetic systems, including metabolic engineering, synthetic biology, and optimization in production process. Since the biosynthesis is not native in microbial hosts such as Escherichia coli, Saccharomyces cerevisiae, and Corynebacterium glutamicum, genetic engineering and manipulation have made it possible. In this review, the discussion will mainly focus on recent progress in production of resveratrol and piceatannol, including the various strategies used for their production.


Assuntos
Engenharia Metabólica , Microrganismos Geneticamente Modificados , Resveratrol/metabolismo , Estilbenos/metabolismo , Vias Biossintéticas , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Biologia Sintética
11.
Appl Microbiol Biotechnol ; 103(19): 7953-7969, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407037

RESUMO

Two sustainable and cost-effective cascade enzymatic systems were developed to regenerate uridine diphosphate (UDP)-α-D-glucose and UDP-ß-L-rhamnose from sucrose. The systems were coupled with the UDP generating glycosylation reactions of UDP sugar-dependent glycosyltransferase (UGT) enzymes mediated reactions. As a result, the UDP generated as a by-product of the GT-mediated reactions was recycled. In the first system, YjiC, a UGT from Bacillus licheniformis DSM 13, was used for transferring glucose from UDP-α-D-glucose to naringenin, in which AtSUS1 from Arabidopsis thaliana was used to synthesize UDP-α-D-glucose and fructose as a by-product from sucrose. In the second system, flavonol 7-O-rhamnosyltransferase (AtUGT89C1) from A. thaliana was used to transfer rhamnose from UDP-ß-L-rhamnose to quercetin, in which AtSUS1 along with UDP-ß-L-rhamnose synthase (AtRHM1), also from A. thaliana, were used to produce UDP-ß-L-rhamnose from the same starter sucrose. The established UDP recycling system for the production of naringenin glucosides was engineered and optimized for several reaction parameters that included temperature, metal ions, NDPs, pH, substrate ratio, and enzymes ratio, to develop a highly feasible system for large-scale production of different derivatives of naringenin and other natural products glucosides, using inexpensive starting materials. The developed system showed the conversion of about 37 mM of naringenin into three different glucosides, namely naringenin, 7-O-ß-D-glucoside, naringenin, 4'-O-ß-D-glucoside, and naringenin, 4',7-O-ß-D-diglucoside. The UDP recycling (RCmax) was 20.10 for naringenin glucosides. Similarly, the conversion of quercetin to quercetin 7-O-α-L-rhamnoside reached a RCmax value of 10.0.


Assuntos
Flavanonas/metabolismo , Glucosídeos/metabolismo , Glucuronosiltransferase/metabolismo , Hexosiltransferases/metabolismo , Quercetina/metabolismo , Sacarose/metabolismo , Arabidopsis/enzimologia , Bacillus licheniformis/enzimologia , Biocatálise , Glucuronosiltransferase/isolamento & purificação , Hexosiltransferases/isolamento & purificação
12.
Appl Microbiol Biotechnol ; 103(19): 8281, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31440791

RESUMO

The name of the author "Yamaguchi Tokutaro" is incorrect for the first and last name has been interchanged. The correct presentation is "Tokutaro Yamaguchi".

13.
Biotechnol Appl Biochem ; 66(4): 484-493, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26498482

RESUMO

Isoflavonoid representatives such as genistein and daidzein are highly potent anticancer, antibacterial, and antioxidant agents. It have been demonstrated that methylation of flavonoids enhanced the transporting ability, which lead to facilitated absorption and greatly increased bioavailability. In this paper, genetically engineered Escherichia coli was reconstructed by harboring E. coli K12-derived metK encoding S-adenosine-l-methionine (SAM) synthase (accession number: K02129) for enhancement of SAM as a precursor and Streptomyces avermitilis originated SaOMT2 (O-methyltransferase, accession number: NP_823558) for methylation of daidzein and genistein as preferred substrates. The formation of desired products via biotransformation including 4'-O-methyl-genistein and 4'-O-methyl-daidzein was confirmed individually by using chromatographical methods such as high-performance liquid chromatography, liquid chromatography/time-of-flight/mass spectrometry (LC-TOF-MS), and nuclear magnetic resonance (NMR), and NMR (1 H and 13 C). Furthermore, substrates concentration, incubation time, and media parameters were optimized using flask culture. Finally, the most fit conditions were applied for fed-batch fermentation with scale-up to 3 L (working volume) to obtain the maximum yield of the products including 164.25 µM (46.81 mg/L) and 382.50 µM (102.88 mg/L) for 4'-O-methyl genistein and 4'-O-methyl daidzein, respectively. In particular, potent inhibitory activities of those isoflavonoid methoxides against the growth of cancer line (B16F10, AGS, and HepG2) and human umbilical vein endothelial cells were investigated and demonstrated. Taken together, this research work described the production of isoflavonoid-4'-O-methoxides by E. coli engineering, improvement of production, characterization of produced compounds, and preliminary in vitro biological activities of the flavonoids being manufactured.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Escherichia coli/metabolismo , Isoflavonas/biossíntese , Isoflavonas/farmacologia , Engenharia Metabólica , Metanol/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Escherichia coli/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Isoflavonas/química , Metanol/química , Metanol/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Molecules ; 24(14)2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31311182

RESUMO

The very well-known bioactive natural product, resveratrol (3,5,4'-trihydroxystilbene), is a highly studied secondary metabolite produced by several plants, particularly grapes, passion fruit, white tea, and berries. It is in high demand not only because of its wide range of biological activities against various kinds of cardiovascular and nerve-related diseases, but also as important ingredients in pharmaceuticals and nutritional supplements. Due to its very low content in plants, multi-step isolation and purification processes, and environmental and chemical hazards issues, resveratrol extraction from plants is difficult, time consuming, impracticable, and unsustainable. Therefore, microbial hosts, such as Escherichia coli, Saccharomyces cerevisiae, and Corynebacterium glutamicum, are commonly used as an alternative production source by improvising resveratrol biosynthetic genes in them. The biosynthesis genes are rewired applying combinatorial biosynthetic systems, including metabolic engineering and synthetic biology, while optimizing the various production processes. The native biosynthesis of resveratrol is not present in microbes, which are easy to manipulate genetically, so the use of microbial hosts is increasing these days. This review will mainly focus on the recent biotechnological advances for the production of resveratrol, including the various strategies used to produce its chemically diverse derivatives.


Assuntos
Engenharia Metabólica/métodos , Proteínas de Plantas/genética , Plantas/química , Resveratrol/metabolismo , Vias Biossintéticas , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/crescimento & desenvolvimento , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Estrutura Molecular , Plantas/genética , Resveratrol/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Biologia Sintética
15.
J Environ Sci (China) ; 75: 84-97, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30473310

RESUMO

A visible light-induced, Cu-doped BiVO4 photocatalyst was synthesized by a microwave hydrothermal method. The photocatalytic efficiency was investigated in the degradation of model water pollutants like Methylene Blue (dye) and ibuprofen (pharmaceuticals), as well as the inactivation of Escherichia coli (bacteria). The Cu-doped BiVO4 samples showed better efficiency than undoped BiVO4, and the 1wt.% Cu-doped BiVO4 sample showed the best efficiency. The degradation of Methylene Blue reached 95%, while the degradation of ibuprofen reached 75%, and the inactivation of E. coli reached 85% in irradiation with visible light. The appearance of additional absorption band shoulders and widening of the optical absorption in the visible range makes the prepared powder an efficient visible light-driven photocatalyst. Moreover, the formation of an in-gap energy state just above the valance band as determined by density functional theory (DFT) first principle calculation, facilitates the wider optical absorption range of the doped system. Similarly, this in-gap energy state also acts as an electron trap, which is favorable for the efficient separation and photoexcited charge carriers' transfer process. The formation of oxygen vacancies due to doping also improved the separation of the charge carrier, which promoted the trapping of electrons and inhibited electron hole recombination, thus increasing the photocatalytic activity. No decrease in the efficiency of the 1wt.% Cu-doped BiVO4 photocatalyst in the degradation of ibuprofen over three consecutive cycles revealed the stability of the photocatalyst towards photocorrosion. These findings highlight the multifunctional applications of Cu-doped BiVO4 in wastewater containing multiple pollutants.


Assuntos
Bismuto/química , Cobre/química , Modelos Químicos , Vanadatos/química , Poluentes Químicos da Água/química , Catálise , Luz , Fotólise , Semicondutores , Eliminação de Resíduos Líquidos , Águas Residuárias/química
16.
Appl Microbiol Biotechnol ; 102(3): 1251-1267, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29308528

RESUMO

Two plant-originated C-glucosyltransferases (CGTs) UGT708D1 from Glycine max and GtUF6CGT1 from Gentiana triflora were accessed for glucosylation of selected flavones chrysin and luteolin. Uridine diphosphate (UDP)-glucose pool was enhanced in Escherichia coli cell cytosol by introducing heterologous UDP-glucose biosynthetic genes, i.e., glucokinase (glk), phosphoglucomutase (pgm2), and glucose 1-phosphate uridylyltransferase (galU), along with glucose facilitator diffusion protein from (glf) from different organisms, in a multi-monocistronic vector with individual T7 promoter, ribosome binding site, and terminator for each gene. The C-glucosylated products were analyzed by high-performance liquid chromatography-photodiode array, high-resolution quadruple time-of-flight electrospray ionization mass spectrometry, and one-dimensional nuclear magnetic resonance analyses. Fed-batch shake flask culture showed 8% (7 mg/L; 16 µM) and 11% (9 mg/L; 22 µM) conversion of chrysin to chrysin 6-C-ß-D-glucoside with UGT708D1 and GtUF6CGT1, respectively. Moreover, the bioengineered E. coli strains with exogenous UDP-glucose biosynthetic genes and glucose facilitator diffusion protein enhanced the production of chrysin 6-C-ß-D-glucoside by approximately 1.4-fold, thus producing 10 mg/L (12%, 24 µM) and 14 mg/L (17%, 34 µM) by UGT708D1 and GtUF6CGT1, respectively, without supplementation of additional UDP-glucose in the medium. The biotransformation was further elevated when the bioengineered strain was scaled up in lab-scale fermentor at 3 L volume. HPLC analysis of fermentation broth extract revealed 50% (42 mg/L, 100 µM) conversion of chrysin to chrysin 6-C-ß-D-glucoside at 48 h upon supplementation of 200 µM of chrysin. The maximum conversion of luteolin was 38% (34 mg/L, 76 µM) in 50-mL shake flask fermentation at 48 h. C-glucosylated derivative of chrysin was found to be more soluble and more stable to high temperature, different pH range, and ß-glucosidase enzyme, than O-glucosylated derivative of chrysin.


Assuntos
Escherichia coli/metabolismo , Flavonas/biossíntese , Glucosídeos/biossíntese , Engenharia Metabólica , Técnicas de Cultura Celular por Lotes , Vias Biossintéticas , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Fermentação , Flavonoides/metabolismo , Gentiana/enzimologia , Glucoquinase/genética , Glucoquinase/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Luteolina/metabolismo , Fosfoglucomutase/genética , Fosfoglucomutase/metabolismo , Glycine max/enzimologia , Espectrometria de Massas por Ionização por Electrospray , Uridina Difosfato Glucose/metabolismo
17.
Appl Microbiol Biotechnol ; 102(22): 9691-9706, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30178203

RESUMO

Resveratrol and its ortho-hydroxylated derivative piceatannol were biosynthesized by modular pathway engineering in Escherichia coli. The biosynthetic pathway was divided into three different modules. Module I includes polyketide biosynthetic genes; module II genes include acetyl-CoA and malonyl-CoA pool-enhancing genes from three different organisms; and module III genes are regiospecific 3'-hydroxylating enzymes. E. coli BL21(DE3) with module I produced 8.6 mg/L of resveratrol from exogenously fed 1 mM p-coumaric acid after 72 h. Combination of module I and acetyl-CoA supplementing module IIb genes from N. farcinica IFM10152 produced 2.5-fold higher (60 mg/L) titer of resveratrol than the module IIa genes from E. coli. The exogenous supplementation of sodium acetate further enhanced production to 64 mg/L. Furthermore, module I with module IIc harboring matBC from S. coelicolor A3(2) produced 73 mg/L of resveratrol, which was elevated to 151 mg/L upon supplementing disodium malonate exogenously. This increment is 17.5-fold higher than module I harboring E. coli BL21(DE3). The combination of module I and two different module II genes yielded 137 mg/L resveratrol when supplemented with both sodium acetate and disodium malonate. The high resveratrol-producing combination module was further modified with incorporation of hpaBC for the ortho-hydroxylation of resveratrol to produce piceatannol. The engineered strain harboring modules I, IIc and III produced 124 mg/L of piceatannol, the highest titer after 72 h in disodium malonate-supplemented strain, which is 2-fold higher than in non-supplemented strain. The remaining resveratrol was about 30 mg/L. Furthermore, caffeic acid (85.5 mg/L) was also produced in the same strain. Resveratrol and piceatannol were biosynthesized along with caffeic acid by three different modules overexpressing acetate and malonate assimilation pathway genes from three different sources. The production titer of both resveratrol and piceatannol could be achieved higher upon blocking acetyl-CoA and malonyl-CoA utilizing pathway genes in host strain.


Assuntos
Escherichia coli/genética , Escherichia coli/metabolismo , Engenharia Metabólica , Resveratrol/metabolismo , Estilbenos/metabolismo , Acetilcoenzima A/metabolismo , Vias Biossintéticas , Escherichia coli/enzimologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Malonil Coenzima A/metabolismo
18.
Biotechnol Appl Biochem ; 65(2): 128-137, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28608479

RESUMO

7,8-Dihydroxyflavone (7,8-DHF) has been conjugated with glucose moiety to produce glucoside derivatives. Three analogues of 7,8-DHF (7-O-ß-d-glucosyl-8-hydroxyflavone, 7-hydroxy-8-O-ß-d-glucosyl flavone, and 7,8-di-O-ß-d-glucosylflavone) have been successfully produced from in vitro reaction using glycosyltransferase of Bacillus licheniformis. Production of these 7,8-DHF derivatives were shifted to cheaper and easier approach in this study by using engineered Escherichia coli BL21 (DE3) ΔpgiΔzwfΔushA cells in which the flow of glucose-6-phospahte toward glycolysis and pentose phosphate pathway and hydrolysis of UDP-α-d-glucose were blocked while directing the carbon flux toward UDP-α-d-glucose by overexpressing UDP-α-d-glucose pathway genes. Supplementation of 300 µM of 7,8-DHF to the culture resulted in production of 171 µM of 7-O-ß-d-glucosyl-8-hydroxyflavone, 68 µM of 7-hydroxy-8-O-ß-d-glucoxyflavone, and 55 µM of 7,8-di-O-ß-d-glucoxyflavone in laboratory-scale 3-L fermentor, representing 98% bioconversion of initially fed substrate to respective glucoside derivatives within 48 H. These products were characterized by high-performance liquid chromatography-photodiode array (HPLC-PDA), HPLC-PDA-quadruple time of flight-electron spray ionization mass spectrometry, and nuclear magnetic resonance analyses. These newly synthesized derivatives were found to be able to interact with amino acids of active site of human ß-site amyloid precursor protein cleaving ß-site amyloid precursor protein cleaving enzyme 1 (BACE1) ß-secretase enzyme in in silico studies, thus displaying possible application in cure of Alzheimer's disease.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Flavonas/metabolismo , Flavonas/farmacologia , Glicosídeos/metabolismo , Glicosídeos/farmacologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Bacillus licheniformis/enzimologia , Bacillus licheniformis/genética , Bacillus licheniformis/metabolismo , Vias Biossintéticas , Inibidores Enzimáticos/química , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/metabolismo , Flavonas/química , Glicosídeos/química , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Humanos , Microbiologia Industrial/métodos , Engenharia Metabólica/métodos , Redes e Vias Metabólicas , Simulação de Acoplamento Molecular
19.
South Med J ; 111(10): 628-633, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30285271

RESUMO

OBJECTIVE: The risk of Clostridium difficile infection (CDI) has not been well studied in patients with lymphoma. We thus sought to determine the risk of CDI in hospitalizations with lymphoma along with its trend, outcomes, and predictors using a large database. METHODS: Hospital discharge data from the Nationwide Inpatient Sample (NIS) from 2007 to 2011 were used for the study. Using the International Classification of Diseases, Ninth Revision, Clinical Modification codes, all adult patients aged 18 years or older having a primary diagnosis of lymphoma were queried for the presence of CDI as any of the secondary diagnoses. The risk of CDI in lymphoma and its yearly trend were assessed. We performed multivariate logistic regression to determine the independent risk factors of CDI in lymphoma. Furthermore, we studied mortality and other adverse outcomes of CDI in patients with lymphoma. RESULTS: There were 236,312 discharges (weighted) with the primary diagnosis of lymphoma. CDI was present in 2.13% of patients with lymphoma versus 0.8% in the nonlymphoma group (P < 0.001). On multivariate analysis, the significant predictors of CDI in lymphoma were presence of infection (odds ratio [OR] 3.1, 95% confidence interval [CI] 2.7-3.6), stem cell transplant (OR 2.7, 95% CI 2.3-3.4), graft-versus-host disease (OR 1.9, 95% CI 1.4-2.8), race (Asian vs white, OR 1.6, 95% CI 1.1-2.4), chemotherapy (OR 1.6, 95% CI 1.4-1.8), gastrointestinal surgery (OR 1.4, 95% CI 1.2-1.7), and Charlson Comorbidity Index (CCI) (CCI of 2 vs 0-1: OR 1.2, 95% CI 1.1-1.4; CCI of 3 vs 0-1: OR 1.3, 95% CI 1.03-1.6). CDI in lymphoma was associated with worse hospital outcomes such as increased mortality (17% vs 8%), increased length of stay (23.6 vs 9.9 days), mean total hospital charges ($197,015 vs $79,392), rate of intubation (13% vs 4% vs 13%), and rate of total parenteral nutrition (11% vs 3%). CONCLUSIONS: Hospitalization with lymphoma was associated with an increased risk of CDI. The significant predictors for CDI in lymphoma were infection, stem cell transplant, graft-versus-host disease, race, chemotherapy, gastrointestinal surgery, and Charlson Comorbidity Index. CDI in lymphoma was associated with increased mortality and other adverse outcomes warranting a need of more vigilance for CDI in patients with lymphoma.


Assuntos
Clostridioides difficile , Infecções por Clostridium/epidemiologia , Linfoma/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Clostridium/diagnóstico , Bases de Dados Factuais , Feminino , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Humanos , Modelos Logísticos , Linfoma/mortalidade , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
20.
Dent Traumatol ; 34(2): 129-134, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29495106

RESUMO

BACKGROUND/AIMS: Traumatic dental injuries of the primary dentition (TDI-p) have a global prevalence of approximately 11%-47%. They have immediate and long-term effects. Original research analysing the long-term sequelae of TDI-p on permanent dentition (LSP) are few in number. The aim of this study was to explore the correlation between age of TDI-p, type of TDI-p and LSP. MATERIAL AND METHODS: Retrospective analysis of patient data from 2008-2017, reporting with LSP due to TDI-p, was performed. Uniform protocols and complete radiographic-photographic records were analysed. There were 638 LSP reported with 596 teeth having complete records. RESULTS: There were 286 children with 153 males (53.5%) and 133 females (46.5%). Mean age of TDI-p causing LSP was 36.57 ± 11.51 months, with severity increasing in the younger age group. The highest number of LSP was associated with avulsion injuries (218, 36.58%), and the odds ratio of the type of TDI-p affect the severity of LSP was 2.0163. Mean age of reporting was 8.54 ± 2.19 years and was lowest for enamel discolorations. Most LSP were not associated with any associated feature (AF), although impaction was highest among all AF (63, 10.57%). CONCLUSION: Age and type of TDI-p affect LSP, with the former being the stronger determinant of its severity. Mean age of reporting of LSP is dependent upon both type of LSP and AF. LSP due to TDI-p can further be graded in terms of severity.


Assuntos
Traumatismos Dentários/complicações , Dente Decíduo , Criança , Dentição Permanente , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Estudos Retrospectivos
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