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1.
Biotechnol Biofuels Bioprod ; 17(1): 14, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281959

RESUMO

BACKGROUND: Recent engineering efforts have targeted the ethanologenic bacterium Zymomonas mobilis for isobutanol production. However, significant hurdles remain due this organism's vulnerability to isobutanol toxicity, adversely affecting its growth and productivity. The limited understanding of the physiological impacts of isobutanol on Z. mobilis constrains our ability to overcome these production barriers. RESULTS: We utilized a systems-level approach comprising LC-MS/MS-based lipidomics, metabolomics, and shotgun proteomics, to investigate how exposure to ethanol and isobutanol impact the lipid membrane composition and overall physiology of Z. mobilis. Our analysis revealed significant and distinct alterations in membrane phospholipid and fatty acid composition resulting from ethanol and isobutanol exposure. Notably, ethanol exposure increased membrane cyclopropane fatty acid content and expression of cyclopropane fatty acid (CFA) synthase. Surprisingly, isobutanol decreased cyclopropane fatty acid content despite robust upregulation of CFA synthase. Overexpression of the native Z. mobilis' CFA synthase increased cyclopropane fatty acid content in all phospholipid classes and was associated with a significant improvement in growth rates in the presence of added ethanol and isobutanol. Heterologous expression of CFA synthase from Clostridium acetobutylicum resulted in a near complete replacement of unsaturated fatty acids with cyclopropane fatty acids, affecting all lipid classes. However, this did not translate to improved growth rates under isobutanol exposure. Correlating with its greater susceptibility to isobutanol, Z. mobilis exhibited more pronounced alterations in its proteome, metabolome, and overall cell morphology-including cell swelling and formation of intracellular protein aggregates -when exposed to isobutanol compared to ethanol. Isobutanol triggered a broad stress response marked by the upregulation of heat shock proteins, efflux transporters, DNA repair systems, and the downregulation of cell motility proteins. Isobutanol also elicited widespread dysregulation of Z. mobilis' primary metabolism evidenced by increased levels of nucleotide degradation intermediates and the depletion of biosynthetic and glycolytic intermediates. CONCLUSIONS: This study provides a comprehensive, systems-level evaluation of the impact of ethanol and isobutanol exposure on the lipid membrane composition and overall physiology of Z. mobilis. These findings will guide engineering of Z. mobilis towards the creation of isobutanol-tolerant strains that can serve as robust platforms for the industrial production of isobutanol from lignocellulosic sugars.

2.
J Infect ; 88(2): 71-76, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37866792

RESUMO

This review details recent findings from the Global Meningococcal Initiative's (GMI) recent meeting on the surveillance and control strategies for invasive meningococcal disease in the Middle East. The nature of case reporting and notification varies across the region, with many countries using bacterial meningitis as an IMD case definition in lieu of meningitis and septicaemia. This may overlook a significant burden associated with IMD leading to underreporting or misreporting of the disease. Based on these current definitions, IMD reported incidence remains low across the region, with historical outbreaks mainly occurring due to the Hajj and Umrah mass gatherings. The use of case confirmation techniques also varies in Middle Eastern countries. While typical microbiological techniques, such as culture and Gram staining, are widely used for characterisation, polymerase chain reaction (PCR) testing is utilised in a small number of countries. PCR testing may be inaccessible for several reasons including sample transportation, cost, or a lack of laboratory expertise. These barriers, not exclusive to PCR use, may impact surveillance systems more broadly. Another concern throughout the region is potentially widespread ciprofloxacin resistance since its use for chemoprophylaxis remains high in many countries.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis , Humanos , Infecções Meningocócicas/epidemiologia , Infecções Meningocócicas/prevenção & controle , Infecções Meningocócicas/microbiologia , Neisseria meningitidis/genética , Oriente Médio/epidemiologia , Surtos de Doenças/prevenção & controle , Incidência , Sorogrupo
3.
Animals (Basel) ; 13(24)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38136921

RESUMO

This study analyzed the effects of an Alliaceae encapsulated extract (AE-e) on daily gain (ADG), feed intake (ADFI), feed conversion ratio (FCR), oocysts per gram of feces (OPG), intestinal lesion (LS), and microbiota composition in broilers challenged with Eimeria spp. A total of 4800 one day Cobb-500 were allotted into 10 treatment groups with 12 replicates of 40 birds in a 2 × 4 + 2 factorial arrangement. The first factor was non-challenged (NC) or challenged (C), the second was four levels of AE-e added in the basal diet, 0 (AE0), 250 (AE250), 500 (AE500), and 750 mg·kg-1 (AE750), plus two ionophore controls, non-challenged (NC-Ion) and challenged (C-Ion). No interactions were observed between factors (NC0, NC250, NC500, NC750, C0, C250, C500, and C750), while C-Ion improved FCR at 21 d. The challenge affected negatively ADG and FCR and promoted enteropathogens in cecum. AE750 improved FCR in the finisher and cumulative phases, while C-Ion had fewer total OPG than C0 and C250. Likewise, at 21d, C250, C500, and C-Ion had fewer LS than C0, while at 28 d, C750 showed lower than C-Ion. In the cecum microbiota, C500 had more Ruminococcus, Firmicutes b, and Intestinimonas than C-Ion. In summary, AE-e showed beneficial results in broilers infected with Eimeria spp.

4.
J Clin Med ; 12(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37959339

RESUMO

Patients with chronic obstructive pulmonary disease (COPD) may experience exacerbations. During severe exacerbations, nutritional and endocrinological comorbidities can play an important role in the clinical and functional aspects of these patients. The aim of this study was to analyse the influence of the presence of diabetes mellitus (DM) and nutritional parameters on the deterioration of symptoms and quality of life during a severe exacerbation in patients with COPD. An observational study was conducted on COPD patients admitted due to an exacerbation. The COPD Assessment Test (CAT) questionnaire was administered, and clinical and functional parameters were compared based on the presence of nutritional and endocrinological alterations. A total of 50 patients were included, of whom 30 (60%) were male. The mean age was 70.5 years (standard deviation (SD) 9.6). The median CAT score during exacerbation was 25 (interquartile range (IQR) 17.5-30), and the baseline score was 13.5 (IQR 7-19), which represented a statistically significant difference (p < 0.001). Patients with iron deficiencies had a lower total CAT score (p = 0.041), specifically for items related to daily activity (p = 0.009) and energy (p = 0.007). Diabetic patients exhibited a greater decline in pulmonary function during exacerbation (p = 0.016), while patients with high thyroid-stimulating hormone (TSH) levels had a shorter hospital stay (p = 0.016). For COPD patients admitted due to an exacerbation, the metabolic assessment is useful and relevant in the clinical set-up, as endocrinological comorbidities negatively affect clinical and functional aspects of these patients.

5.
mBio ; : e0148723, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37905909

RESUMO

Reduced genome bacteria are genetically simplified systems that facilitate biological study and industrial use. The free-living alphaproteobacterium Zymomonas mobilis has a naturally reduced genome containing fewer than 2,000 protein-coding genes. Despite its small genome, Z. mobilis thrives in diverse conditions including the presence or absence of atmospheric oxygen. However, insufficient characterization of essential and conditionally essential genes has limited broader adoption of Z. mobilis as a model alphaproteobacterium. Here, we use genome-scale CRISPRi-seq (clustered regularly interspaced short palindromic repeats interference sequencing) to systematically identify and characterize Z. mobilis genes that are conditionally essential for aerotolerant or anaerobic growth or are generally essential across both conditions. Comparative genomics revealed that the essentiality of most "generally essential" genes was shared between Z. mobilis and other Alphaproteobacteria, validating Z. mobilis as a reduced genome model. Among conditionally essential genes, we found that the DNA repair gene, recJ, was critical only for aerobic growth but reduced the mutation rate under both conditions. Further, we show that genes encoding the F1FO ATP synthase and Rhodobacter nitrogen fixation (Rnf) respiratory complex are required for the anaerobic growth of Z. mobilis. Combining CRISPRi partial knockdowns with metabolomics and membrane potential measurements, we determined that the ATP synthase generates membrane potential that is consumed by Rnf to power downstream processes. Rnf knockdown strains accumulated isoprenoid biosynthesis intermediates, suggesting a key role for Rnf in powering essential biosynthetic reactions. Our work establishes Z. mobilis as a streamlined model for alphaproteobacterial genetics, has broad implications in bacterial energy coupling, and informs Z. mobilis genome manipulation for optimized production of valuable isoprenoid-based bioproducts. IMPORTANCE The inherent complexity of biological systems is a major barrier to our understanding of cellular physiology. Bacteria with markedly fewer genes than their close relatives, or reduced genome bacteria, are promising biological models with less complexity. Reduced genome bacteria can also have superior properties for industrial use, provided the reduction does not overly restrict strain robustness. Naturally reduced genome bacteria, such as the alphaproteobacterium Zymomonas mobilis, have fewer genes but remain environmentally robust. In this study, we show that Z. mobilis is a simplified genetic model for Alphaproteobacteria, a class with important impacts on the environment, human health, and industry. We also identify genes that are only required in the absence of atmospheric oxygen, uncovering players that maintain and utilize the cellular energy state. Our findings have broad implications for the genetics of Alphaproteobacteria and industrial use of Z. mobilis to create biofuels and bioproducts.

6.
ACS Nano ; 17(10): 9429-9441, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37134221

RESUMO

Insoluble amyloid fibrils made from proteins and peptides are difficult to be degraded in both living and artificial systems. The importance of studying their physical stability lies primarily with their association with human neurodegenerative diseases, but also owing to their potential role in multiple bio-nanomaterial applications. Here, gold nanorods (AuNRs) were utilized to investigate the plasmonic heating properties and dissociation of amyloid-ß fibrils formed by different peptide fragments (Aß16-22/Aß25-35/Aß1-42) related to the Alzheimer's disease. It is demonstrated that AuNRs were able to break mature amyloid-ß fibrils from both the full length (Aß1-42) and peptide fragments (Aß16-22/Aß25-35) within minutes by triggering ultrahigh localized surface plasmon resonance (LSPR) heating. The LSPR energy absorbed by the amyloids to unfold and move to higher levels in the protein folding energy landscape can be measured directly and in situ by luminescence thermometry using lanthanide-based upconverting nanoparticles. We also show that Aß16-22 fibrils, with the largest persistence length, displayed the highest resistance to breakage, resulting in a transition from rigid fibrils to short flexible fibrils. These findings are consistent with molecular dynamics simulations indicating that Aß16-22 fibrils possess the highest thermostability due to their highly ordered hydrogen bond networks and antiparallel ß-sheet orientation, hence affected by an LSPR-induced remodeling rather than melting. The present results introduce original strategies for disassembling amyloid fibrils noninvasively in liquid environment; they also introduce a methodology to probe the positioning of amyloids on the protein folding and aggregation energy landscape via nanoparticle-enabled plasmonic and upconversion nanothermometry.


Assuntos
Amiloide , Calefação , Humanos , Amiloide/química , Peptídeos beta-Amiloides/química , Dobramento de Proteína , Fragmentos de Peptídeos/química , Lasers
7.
Int J Mol Sci ; 24(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37240407

RESUMO

The reactivity of the new flexible potentially pentadentate N3O2 aminophenol ligand H4Lr (2,2'-((pyridine-2,6-diylbis(methylene))bis(azanediyl))diphenol) towards different dysprosium salts and holmium(III) nitrate was investigated. Accordingly, this reactivity seems to greatly depend on the metal ion and salt employed. In this way, the reaction of H4Lr with dysprosium(III) chloride in air leads to the oxo-bridged tetranuclear complex [Dy4(H2Lr)3(Cl)4(µ3-O)(EtOH)2(H2O)2]·2EtOH·H2O (1·2EtOH·H2O), while the same reaction just changing the chloride salt by the nitrate one renders the peroxo-bridged pentanuclear compound [Dy5(H2Lr)2(H2.5Lr)2(NO3)4(µ3-O2)2]·2H2O (2·2H2O), where both peroxo ligands seem to come from the fixation and reduction of atmospheric oxygen. However, if holmium(III) nitrate is used instead of dysprosium(III) nitrate, no evidence of a peroxide ligand is observed, and the dinuclear complex {[Ho2(H2Lr)(H3Lr)(NO3)2(H2O)2](NO3)} 2.5H2O (3·2.5H2O) is isolated. The three complexes were unequivocally characterized by X-ray diffraction techniques, and their magnetic properties were analyzed. Thus, while the Dy4 and Ho2 complexes do not show magnet-like behavior even in the presence of an external magnetic field, 2·2H2O is a single molecule magnet, with an Ueff barrier of 61.2 K (43.2 cm-1). This is the first homonuclear lanthanoid peroxide SMM, which also shows the highest barrier among the reported 4f/3d peroxide zero field SMMs to date.


Assuntos
Aminofenóis , Imãs , Disprósio , Hólmio , Ligantes , Nitratos , Cloretos , Oxigênio
8.
mSystems ; 8(2): e0009223, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36995223

RESUMO

Zymomonas mobilis is an industrially relevant aerotolerant anaerobic bacterium that can convert up to 96% of consumed glucose to ethanol. This highly catabolic metabolism could be leveraged to produce isoprenoid-based bioproducts via the methylerythritol 4-phosphate (MEP) pathway, but we currently have limited knowledge concerning the metabolic constraints of this pathway in Z. mobilis. Here, we performed an initial investigation of the metabolic bottlenecks within the MEP pathway of Z. mobilis using enzyme overexpression strains and quantitative metabolomics. Our analysis revealed that 1-deoxy-d-xylulose 5-phosphate synthase (DXS) represents the first enzymatic bottleneck in the Z. mobilis MEP pathway. DXS overexpression triggered large increases in the intracellular levels of the first five MEP pathway intermediates, of which the buildup in 2-C-methyl-d-erythritol 2,4-cyclodiphosphate (MEcDP) was the most substantial. The combined overexpression of DXS, 4-hydroxy-3-methylbut-2-enyl diphosphate (HMBDP) synthase (IspG), and HMBDP reductase (IspH) mitigated the bottleneck at MEcDP and mobilized carbon to downstream MEP pathway intermediates, indicating that IspG and IspH activity become the primary pathway constraints during DXS overexpression. Finally, we overexpressed DXS with other native MEP enzymes and a heterologous isoprene synthase and showed that isoprene can be used as a carbon sink in the Z. mobilis MEP pathway. By revealing key bottlenecks within the MEP pathway of Z. mobilis, this study will aid future engineering efforts aimed at developing this bacterium for industrial isoprenoid production. IMPORTANCE Engineered microorganisms have the potential to convert renewable substrates into biofuels and valuable bioproducts, which offers an environmentally sustainable alternative to fossil-fuel-derived products. Isoprenoids are a diverse class of biologically derived compounds that have commercial applications as various commodity chemicals, including biofuels and biofuel precursor molecules. Thus, isoprenoids represent a desirable target for large-scale microbial generation. However, our ability to engineer microbes for the industrial production of isoprenoid-derived bioproducts is limited by an incomplete understanding of the bottlenecks in the biosynthetic pathway responsible for isoprenoid precursor generation. In this study, we combined genetic engineering with quantitative analyses of metabolism to examine the capabilities and constraints of the isoprenoid biosynthetic pathway in the industrially relevant microbe Zymomonas mobilis. Our integrated and systematic approach identified multiple enzymes whose overexpression in Z. mobilis results in an increased production of isoprenoid precursor molecules and mitigation of metabolic bottlenecks.


Assuntos
Zymomonas , Zymomonas/genética , Biocombustíveis , Composição de Bases , Análise de Sequência de DNA , Filogenia , RNA Ribossômico 16S/metabolismo , Terpenos/metabolismo , Fosfatos/metabolismo
9.
Animals (Basel) ; 13(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36978663

RESUMO

This study analyzed the effects of different dietary doses of encapsulated propyl propane thiosulfonate (Pe-PTSO) on the apparent ileal digestibility (AID) of nutrients and productive performance in broilers. A total of 100 one-day-old Cobb 500 were housed in battery cages for 20 days. At 10 days of age, the birds were assigned to one of five diets: negative control (P0), 250 mg/kg of Pe-PTSO (P250), 500 mg/kg of Pe-PTSO (P500), 750 mg/kg of Pe-PTSO (P750), and positive control, nicarbazin-narasin (ION). Titanium dioxide was the external marker, which was added to the diets from day 17 to 20. In the birds fed the P250 diet, there was a significant difference (p ≤ 0.05) in the AID values for amino acids and energy compared to those that consumed the P0 diet. Furthermore, the P250 diet significantly increased (p ≤ 0.05) the average daily weight gain compared to the P0 diet. No significant differences were observed between treatments in average daily feed intake and feed conversion ratio. In summary, the inclusion of 250 mg of encapsulated PTSO per kg in broiler chickens diet improved the digestibility of amino acids and energy, as well as weight gain.

10.
N Engl J Med ; 388(5): 427-438, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36724329

RESUMO

BACKGROUND: In September 2015, the four-component, protein-based meningococcal serogroup B vaccine (4CMenB; Bexsero) became available for private purchase in Spain. METHODS: We conducted a nationwide matched case-control study to assess the effectiveness of 4CMenB in preventing invasive meningococcal disease in children. The study included all laboratory-confirmed cases of invasive meningococcal disease in children younger than 60 months of age between October 5, 2015, and October 6, 2019, in Spain. Each case patient was matched with four controls according to date of birth and province. 4CMenB vaccination status of the case patients and controls was compared with the use of multivariate conditional logistic regression. RESULTS: We compared 306 case patients (243 [79.4%] with serogroup B disease) with 1224 controls. A total of 35 case patients (11.4%) and 298 controls (24.3%) had received at least one dose of 4CMenB. The effectiveness of complete vaccination with 4CMenB (defined as receipt of at least 2 doses, administered in accordance with the manufacturer's recommendations) was 76% (95% confidence interval [CI], 57 to 87) against invasive meningococcal disease caused by any serogroup, and partial vaccination was 54% (95% CI, 18 to 74) effective. Complete vaccination resulted in an effectiveness of 71% (95% CI, 45 to 85) against meningococcal serogroup B disease. Vaccine effectiveness with at least one dose of 4CMenB was 64% (95% CI, 41 to 78) against serogroup B disease and 82% (95% CI, 21 to 96) against non-serogroup B disease. With the use of the genetic Meningococcal Antigen Typing System, serogroup B strains that were expected to be covered by 4CMenB were detected in 44 case patients, none of whom had been vaccinated. CONCLUSIONS: Complete vaccination with 4CMenB was found to be effective in preventing invasive disease by serogroup B and non-serogroup B meningococci in children younger than 5 years of age.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis Sorogrupo B , Criança , Humanos , Lactente , Estudos de Casos e Controles , Infecções Meningocócicas/microbiologia , Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/uso terapêutico , Neisseria meningitidis , Espanha
11.
Metab Eng ; 76: 18-28, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36626963

RESUMO

Plants produce many high-value oleochemical molecules. While oil-crop agriculture is performed at industrial scales, suitable land is not available to meet global oleochemical demand. Worse, establishing new oil-crop farms often comes with the environmental cost of tropical deforestation. The field of metabolic engineering offers tools to transplant oleochemical metabolism into tractable hosts while simultaneously providing access to molecules produced by non-agricultural plants. Here, we evaluate strategies for rewiring metabolism in the oleaginous yeast Yarrowia lipolytica to synthesize a foreign lipid, 3-acetyl-1,2-diacyl-sn-glycerol (acTAG). Oils made up of acTAG have a reduced viscosity and melting point relative to traditional triacylglycerol oils making them attractive as low-grade diesels, lubricants, and emulsifiers. This manuscript describes a metabolic engineering study that established acTAG production at g/L scale, exploration of the impact of lipid bodies on acTAG titer, and a techno-economic analysis that establishes the performance benchmarks required for microbial acTAG production to be economically feasible.


Assuntos
Yarrowia , Triglicerídeos/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Engenharia Metabólica , Metabolismo dos Lipídeos , Óleos/metabolismo
12.
Microorganisms ; 12(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38257857

RESUMO

BACKGROUND: Children and adolescents living with HIV (CALHIV) are at high risk of meningococcal infections and may present lower immune responses to vaccines. The objectives of this study were to assess the immunogenicity of the quadrivalent Men ACWY-TT vaccine (Nimenrix®) in CALHIV after a two-dose schedule and to describe possible HIV-related factors that may affect the immunogenic response. METHODS: A multicenter prospective study was designed, including CALHIV followed in five hospitals in Madrid, between 2019 and 2021. Two doses of the Men ACWY-TT vaccine were administered. Serum bactericidal antibody (SBA) assays using rabbit complement (rSBA) against serogroups C, W, and Y were used to determine seroprotection and vaccine response (the proportion achieving a putative protective titer of ≥eight or a ≥four-fold rise in titer from baseline). Serum was collected at baseline, and at 3 and 12 months after vaccination. RESULTS: There were 29 CALHIV included, 76% of whom were perinatally infected. All were receiving TAR and presented a good immunovirological and clinical status overall. At baseline, 45% of CALHIV had seroprotective titers to at least one serogroup, with individual seroprotection rates of 24%, 28%, and 32% against C, W, and Y, respectively. After a two-dose schedule, vaccine response was 83% for each serogroup, eliciting a vaccine response to all serogroups in 69% of them. One year after vaccination, 75% of CALHIV maintained seroprotective titers against the C serogroup, and 96% against W and Y. None of the HIV-related characteristics analyzed could predict vaccine response or antibody duration. CONCLUSIONS: CALHIV who received effective TAR and presented a good immuno-virological situation achieved an appropriate vaccine response after two doses of the Men ACWY-TT vaccine, and antibody-mediated protection against serogroups C, W, and Y was maintained in more than 70% of the patients one year after vaccination.

13.
J Infect ; 85(6): 611-622, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36273639

RESUMO

This review summarizes the recent Global Meningococcal Initiative (GMI) regional meeting, which explored meningococcal disease in North America. Invasive meningococcal disease (IMD) cases are documented through both passive and active surveillance networks. IMD appears to be decreasing in many areas, such as the Dominican Republic (2016: 18 cases; 2021: 2 cases) and Panama (2008: 1 case/100,000; 2021: <0.1 cases/100,000); however, there is notable regional and temporal variation. Outbreaks persist in at-risk subpopulations, such as people experiencing homelessness in the US and migrants in Mexico. The recent emergence of ß-lactamase-positive and ciprofloxacin-resistant meningococci in the US is a major concern. While vaccination practices vary across North America, vaccine uptake remains relatively high. Monovalent and multivalent conjugate vaccines (which many countries in North America primarily use) can provide herd protection. However, there is no evidence that group B vaccines reduce meningococcal carriage. The coronavirus pandemic illustrates that following public health crises, enhanced surveillance of disease epidemiology and catch-up vaccine schedules is key. Whole genome sequencing is a key epidemiological tool for identifying IMD strain emergence and the evaluation of vaccine strain coverage. The Global Roadmap on Defeating Meningitis by 2030 remains a focus of the GMI.


Assuntos
Meningite Meningocócica , Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis , Humanos , Incidência , Infecções Meningocócicas/epidemiologia , Infecções Meningocócicas/prevenção & controle , Neisseria meningitidis/genética , Vacinas Conjugadas , Meningite Meningocócica/epidemiologia
14.
Dalton Trans ; 51(40): 15593-15600, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36169354

RESUMO

The tetranuclear linear complex [Dy4(1,1,4-H3Lr)2(OAc)6]·CH3OH (1·CH3OH) was satisfactorily prepared and characterized. Its X-ray structure shows that it contains two types of octacoordinated DyIII ions, with distorted triangular dodecahedral and square antiprism geometries. This complex is an SMM, with multiple relaxation pathways, and with an anisotropic energy barrier of 39.7 K. 1·CH3OH also operates as a luminescent thermometer in the 11-295 K range, with a maximum relative thermal sensitivity of 1.6% K-1 and a minimum temperature uncertainty of 1.1 K at 295 K. Thus, 1·CH3OH is the first Dy4 SMM with luminescent thermometry, and this system is a rare example of dysprosium SMM that accesses the thermometric characteristics involving the ligand ascribed to the triplet emission in combination with DyIII emission.

15.
Nanomaterials (Basel) ; 12(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35889725

RESUMO

Since the discovery of Quantum Dots (QDs) by Alexey I. Ekimov in 1981, the interest of researchers in that particular type of nanomaterials (NMs) with unique optical and electrical properties has been increasing year by year. Thus, since 2009, the number of scientific articles published on this topic has not been less than a thousand a year. The increasing use of QDs due to their biomedical, pharmaceutical, biological, photovoltaics or computing applications, as well as many other high-tech uses such as for displays and solid-state lighting (SSL), has given rise to a considerable number of studies about its potential toxicity. However, there are a really low number of reported studies on the detection and quantification of QDs, and these include ICP-MS and electrochemical analysis, which are the most common quantification techniques employed for this purpose. The knowledge of chemical phenomena occurring on the surface of QDs is crucial for understanding the interactions of QDs with species dissolved in the dispersion medium, while it paves the way for a widespread use of chemosensors to facilitate its detection. Keeping in mind both human health and environmental risks of QDs as well as the scarcity of analytical techniques and methodological approaches for their detection, the adaptation of existing techniques and methods used with other NMs appears necessary. In order to provide a multidisciplinary perspective on QD detection, this review focused on three interrelated key aspects of QDs: properties, surface chemistry and detection.

16.
Inorg Chem ; 61(26): 9946-9959, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35737854

RESUMO

A new synthetic method allows isolating fluoride-bridged complexes Bu4N{[M(3NO2,5Br-H3L1,1,4)]2(µ-F)} (M = Dy, 1; M = Ho, 2; M = Gd, 3) and Bu4N{[Dy(3Br,5Cl-H3L1,2,4)]2(µ-F)}·2H2O, 4·2H2O. The crystal structures of 1·5CH3C6H5,·2·2H2O·0.75THF, 3, and 4·2H2O·2THF show that all of them are dinuclear compounds with linear single fluoride bridges and octacoordinated metal centers. Magnetic susceptibility measurements in the temperature range of 2-300 K reveal that the GdIII ions in 3 are weakly antiferromagnetically coupled, and this constitutes the first crystallographically and magnetically analyzed gadolinium complex with a fluoride bridge. Variable-temperature magnetization demonstrates a poor magnetocaloric effect for 3. Alternating current magnetic measurements for 1, 2, and 4·2H2O bring to light that 4·2H2O is an SMM, 1 shows an SMM-like behavior under a magnetic field of 600 Oe, while 2 does not show relaxation of the magnetization even under an applied magnetic field. In spite of this, 2 is the first fluoride-bridged holmium complex magnetically analyzed. DFT and ab initio calculations support the experimental magnetic results and show that apparently small structural differences between 1 and 4·2H2O introduce important changes in the dipolar interactions, from antiferromagnetic in 1 to ferromagnetic in 4·2H2O.

17.
Anal Chem ; 94(4): 1965-1973, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35044165

RESUMO

While much effort has been placed on comprehensive quantitative proteome analysis, certain applications demand the measurement of only a few target proteins from complex systems. Traditional approaches to targeted proteomics rely on nanoliquid chromatography (nLC) and targeted mass spectrometry (MS) methods, e.g., parallel reaction monitoring (PRM). However, the time requirement for nLC can limit the throughput of targeted proteomics. To achieve rapid and high-throughput targeted methods, here we show that nLC separations can be eliminated and replaced with direct infusion shotgun proteome analysis (DISPA) using high-field asymmetric waveform ion mobility spectrometry (FAIMS) with PRM. We demonstrate the application of DISPA-PRM for rapid targeted quantification of bacterial enzymes utilized in the production of biofuels by monitoring temporal expression in 72 metabolically engineered bacterial cultures in less than 2.5 h, with a measured dynamic range >1200-fold. We conclude that DISPA-PRM presents a valuable innovative tool with results comparable to nLC-MS/MS, enabling fast and rapid detection of targeted proteins in complex mixtures.


Assuntos
Proteoma , Espectrometria de Massas em Tandem , Espectrometria de Mobilidade Iônica , Proteoma/análise , Proteômica/métodos
18.
Open Respir Arch ; 4(4): 100212, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37496957

RESUMO

Introduction: Chronic obstructive pulmonary disease (COPD) is a respiratory pathology with high prevalence, morbidity and mortality. The Spanish COPD guideline (GesEPOC) recommends individualizing treatment according to phenotypes. The phenotype classification was updated in 2021. This study aimed to determine the survival of patients by this new classification and compare the predictive capacity of mortality compared to the previous version. Methods: This observational study of COPD patients involved prospective follow-up for 6 years. Demographic and clinical data were collected at the beginning and evolutionary data at the end of the study. Patients were classified according to GesEPOC 2017 and GesEPOC 2021. Univariate survival analysis and multivariate analysis identified mortality risk factors. Results: Of the 273 patients, 243 (89.0%) were male. Ninety-three patients (34.1%) died during follow-up. Regarding phenotypes, 190 patients (69.6%) were non-exacerbators, 69 (25.3%) belonged to the non-eosinophilic exacerbator phenotype and 14 (5.1%) were of the eosinophilic exacerbator phenotype. Compared with non-exacerbator patients, those with the non-eosinophilic exacerbator phenotype had lower survival (p = 0.009). Risk factors independently associated with mortality were older age (p < 0.001), non-eosinophilic exacerbator phenotype (p = 0.017) and a high Charlson index score (p < 0.001). The new classification presented a worse ability to predict mortality than the previous version (area under the curve 0.632 vs 0.566, p = 0.018). Conclusion: Patients with the non-eosinophilic exacerbator phenotype had worse prognoses. This phenotype, advanced age and high comorbidity were mortality risk factors. The GesEPOC 2021 classification predicts mortality worse than the 2017 version. These data must be considered for more individualized management of COPD patients.


Introducción: La enfermedad obstructiva crónica (EPOC) es una patología respiratoria con elevada prevalencia y alta morbimortalidad. La guía española de la EPOC (GesEPOC) recomienda individualizar el tratamiento según fenotipos. En su última actualización en 2021, se ha actualizado la clasificación de fenotipos. Se realiza este estudio para conocer la supervivencia de los pacientes sobre esta nueva clasificación y para comparar la capacidad predictiva de mortalidad con respecto a la versión previa. Métodos: Estudio observacional de pacientes con EPOC con un seguimiento prospectivo durante 6 años. Se recogieron datos demográficos y clínicos al inicio y datos evolutivos al final del estudio. Se clasificó a los pacientes según GesEPOC 2017 y GesEPOC 2021. Se realizó un análisis univariante de supervivencia y un análisis multivariante para identificar factores de riesgo de mortalidad. Resultados: Del los 273 pacientes, 243 (89,0%) eran varones. Fallecieron 93 sujetos (34,1%) durante el seguimiento. En cuanto a los fenotipos, 190 pacientes (69,6%) eran no agudizadores, 69 (25,3%) pertenecían al fenotipo agudizador no eosinofílico, y 14 (5,1%) eran del fenotipo agudizador eosinofílico. Comparando con los enfermos no agudizadores, los del fenotipo agudizador no eosinofílico tuvieron una menor supervivencia (p = 0,009). Los factores de riesgo independientemente asociados a la mortalidad fueron la edad avanzada (p < 0,001), el fenotipo agudizador no eosinofílico (p = 0,017) y una puntuación elevada en el índice de Charlson (p < 0,001). La nueva clasificación presentó una peor capacidad para predecir mortalidad en comparación con la versión previa (área bajo curva 0,632 vs 0,566, p = 0,018). Conclusión: Los pacientes del fenotipo agudizador no eosinofílico tenían peor pronóstico. Este fenotipo, junto con la edad avanzada y la elevada comorbilidad, fueron factores de riesgo de mortalidad. La clasificación GesEPOC 2021 predice peor la mortalidad con respecto a la versión de 2017. Es importante tener estos datos en cuenta para ofrecer un manejo más individualizado a los pacientes con EPOC.

19.
J Infect ; 84(3): 289-296, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34838594

RESUMO

This review article incorporates information from the 4th Global Meningococcal Initiative summit meeting. Since the introduction of stringent COVID-19 infection control and lockdown measures globally in 2020, there has been an impact on IMD prevalence, surveillance, and vaccination compliance. Incidence rates and associated mortality fell across various regions during 2020. A reduction in vaccine uptake during 2020 remains a concern globally. In addition, several Neisseria meningitidis clonal complexes, particularly CC4821 and CC11, continue to exhibit resistance to antibiotics, with resistance to ciprofloxacin or beta-lactams mainly linked to modifications of gyrA or penA alleles, respectively. Beta-lactamase acquisition was also reported through horizontal gene transfer (blaROB-1) involving other bacterial species. Despite the challenges over the past year, progress has also been made on meningococcal vaccine development, with several pentavalent (serogroups ABCWY and ACWYX) vaccines currently being studied in late-stage clinical trial programmes.


Assuntos
COVID-19 , Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Humanos , Infecções Meningocócicas/epidemiologia , Infecções Meningocócicas/microbiologia , Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/uso terapêutico , Neisseria meningitidis/genética , SARS-CoV-2 , Sorogrupo
20.
Crit Rev Biotechnol ; 42(6): 827-837, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34538152

RESUMO

Pressure-driven membrane-based technologies, such as microfiltration (MF), ultrafiltration (UF), and nanofiltration (NF), have been successfully implemented in recovering different types of biomolecules and high-value-added compounds from various streams. Especially, UF membranes meet the requirements for separating specific bioproducts in downstream processes, e.g. monoclonal antibodies (mAbs), which are recognized as proteins produced mainly by plasma cells. According to the importance and functionality of the mAbs, their recovery is a current challenge with these bioseparations. Nevertheless, mAbs recovery using UF-assisted processes has been smartly performed over the last decade. To the best of our knowledge, there are no reviews of the reported developments using UF technology toward mAbs separation. Therefore, the goal of this paper is to collect and elucidate ongoing research studies implemented for the featured separation of mAbs and other biotechnological protein-type molecules (e.g. adenovirus serotype, extracellular vesicles, red fluorescent protein, cyanovirin-N, among others) via ultrafiltration-aided systems. The literature evidence (e.g. research papers, patents, etc.) has been analyzed and discussed according to the purpose of the study. Importantly, the relevant findings and novel approaches are discussed in detail. To finalize this document, the advantages, drawbacks, and guidelines in applying membrane-based techniques for such a recovery are presented.


Assuntos
Ultrafiltração , Purificação da Água , Anticorpos Monoclonais , Biotecnologia , Membranas Artificiais , Ultrafiltração/métodos , Purificação da Água/métodos
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