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1.
Am J Hum Biol ; : e24080, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38562064

RESUMO

OBJECTIVE: The aim was to (1) estimate the relationship between physical fitness (PF) and object control fundamental movement skills (FMS), (2) identify child characteristics that relate with PF and FMS, and (3) examine associations between the school environment, PF, and FMS. METHODS: The sample included 1014 Portuguese children aged 6-10 years from the REACT project. PF was assessed via running speed, shuttle run, standing long jump, handgrip, and the PACER test. Object control FMS were assessed with stationary dribble, kick, catch, overhand throw, and underhand roll. Test performances were transformed into z-scores, and their sum was expressed as overall PF and FMS. Child-level variables included body mass index (BMI) z-scores, accelerometer-measured sedentary time and moderate-to-vigorous physical activity, and socioeconomic status (SES). School size, physical education classes, practice areas, and equipment were also assessed. RESULTS: Approximately, 90% of the variance in object control PF and FMS was at the child level, and 10% at the school level. The correlation between PF and object control FMS was .62, which declined to .43 with the inclusion of covariates. Older, more active, and higher SES children had higher object control PF and FMS, and boys outperformed girls. BMI was negatively associated with PF but not with object control FMS. Sedentary time and number of physical education classes were not significant predictors. Most school predictors did not jointly associate with PF and object control FMS. CONCLUSION: PF and object control FMS z-scores were moderately related. Not all child characteristics were associated with both PF and object control FMS, and their effect sizes were different. School characteristics only explained 10% of the total variation in PF and object control FMS.

2.
Sensors (Basel) ; 24(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38676159

RESUMO

The presence of green areas in urbanized cities is crucial to reduce the negative impacts of urbanization. However, these areas can influence the signal quality of IoT devices that use wireless communication, such as LoRa technology. Vegetation attenuates electromagnetic waves, interfering with the data transmission between IoT devices, resulting in the need for signal propagation modeling, which considers the effect of vegetation on its propagation. In this context, this research was conducted at the Federal University of Pará, using measurements in a wooded environment composed of the Pau-Mulato species, typical of the Amazon. Two machine learning-based propagation models, GRNN and MLPNN, were developed to consider the effect of Amazonian trees on propagation, analyzing different factors, such as the transmitter's height relative to the trunk, the beginning of foliage, and the middle of the tree canopy, as well as the LoRa spreading factor (SF) 12, and the co-polarization of the transmitter and receiver antennas. The proposed models demonstrated higher accuracy, achieving values of root mean square error (RMSE) of 3.86 dB and standard deviation (SD) of 3.8614 dB, respectively, compared to existing empirical models like CI, FI, Early ITU-R, COST235, Weissberger, and FITU-R. The significance of this study lies in its potential to boost wireless communications in wooded environments. Furthermore, this research contributes to enhancing more efficient and robust LoRa networks for applications in agriculture, environmental monitoring, and smart urban infrastructure.

3.
J Antimicrob Chemother ; 77(11): 3163-3172, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36059128

RESUMO

OBJECTIVES: To study the in vitro activity of imipenem/relebactam and comparators and the imipenem/relebactam resistance mechanisms in a Pseudomonas aeruginosa collection from Portugal (STEP, 2017-18) and Spain (SUPERIOR, 2016-17) surveillance studies. METHODS: P. aeruginosa isolates (n = 474) were prospectively recovered from complicated urinary tract (cUTI), complicated intra-abdominal (cIAI) and lower respiratory tract (LRTI) infections in 11 Portuguese and 8 Spanish ICUs. MICs were determined (ISO broth microdilution). All imipenem/relebactam-resistant P. aeruginosa isolates (n = 30) and a subset of imipenem/relebactam-susceptible strains (n = 32) were characterized by WGS. RESULTS: Imipenem/relebactam (93.7% susceptible), ceftazidime/avibactam (93.5% susceptible) and ceftolozane/tazobactam (93.2% susceptible) displayed comparable activity. The imipenem/relebactam resistance rate was 6.3% (Portugal 5.8%; Spain 8.9%). Relebactam restored imipenem susceptibility to 76.9% (103/134) of imipenem-resistant isolates, including MDR (82.1%; 32/39), XDR (68.8%; 53/77) and difficult-to-treat (DTR) isolates (67.2%; 45/67). Among sequenced strains, differences in population structure were detected depending on the country: clonal complex (CC)175 and CC309 in Spain and CC235, CC244, CC348 and CC253 in Portugal. Different carbapenemase gene distributions were also found: VIM-20 (n = 3), VIM-1 (n = 2), VIM-2 (n = 1) and VIM-36 (n = 1) in Spain and GES-13 (n = 13), VIM-2 (n = 3) and KPC-3 (n = 2) in Portugal. GES-13-CC235 (n = 13) and VIM type-CC175 (n = 5) associations were predominant in Portugal and Spain, respectively. Imipenem/relebactam showed activity against KPC-3 strains (2/2), but was inactive against all GES-13 producers and most of the VIM producers (8/10). Mutations in genes affecting porin inactivation, efflux pump overexpression and LPS modification might also be involved in imipenem/relebactam resistance. CONCLUSIONS: Microbiological results reinforce imipenem/relebactam as a potential option to treat cUTI, cIAI and LRTI caused by MDR/XDR P. aeruginosa isolates, except for GES-13 and VIM producers.


Assuntos
Infecções por Pseudomonas , Infecções Respiratórias , Humanos , Pseudomonas aeruginosa/genética , Portugal , Infecções por Pseudomonas/microbiologia , Espanha , Compostos Azabicíclicos/farmacologia , Imipenem/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Unidades de Terapia Intensiva , Infecções Respiratórias/microbiologia
4.
Sensors (Basel) ; 22(14)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35890914

RESUMO

The 5G deployment brings forth the usage of Unmanned Aerial Vehicles (UAV) to assist wireless networks by providing improved signal coverage, acting as relays or base-stations. Another technology that could help achieve 5G massive machine-type communications (mMtc) goals is the Long Range Wide-Area Network (LoRaWAN) communication protocol. This paper studied these complementary technologies, LoRa and UAV, through measurement campaigns in suburban, densely forested environments. Downlink and uplink communication at different heights and spreading factors (SF) demonstrate distinct behavior through our analysis. Moreover, a neural network was trained to predict the measured signal-to-noise ratio (SNR) behavior and results compared with SNR regression models. For the downlink scenario, the neural network results show a root mean square error (RMSE) variation between 1.2322-1.6623 dB, with an error standard deviation (SD) less than 1.6730 dB. For the uplink, the RMSE variation was between 0.8714-1.3891 dB, with an error SD less than 1.1706 dB.


Assuntos
Redes de Comunicação de Computadores , Redes Neurais de Computação , Razão Sinal-Ruído
5.
Sensors (Basel) ; 22(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080959

RESUMO

The Internet of Things (IoT) device scenario has several emerging technologies. Among them, Low-Power Wide-Area Networks (LPWANs) have proven to be efficient connections for smart devices. These devices communicate through gateways that exchange points with the central server. This study proposes an empirical and statistical methodology based on measurements carried out in a typical scenario of Amazonian cities composed of forests and buildings on the Campus of the Federal University of Pará (UFPA) to apply an adjustment to the coefficients in the UFPA propagation model. Furthermore, an Evolutionary Particle Swarm Optimization (EPSO) metaheuristic with multi-objective optimization was applied to maximize the coverage area and minimize the number of gateways to assist in the planning of a LoRa network. The results of simulations using the Monte Carlo method show that the EPSO-based gateway placement optimization methodology can be used to plan future LPWAN networks. As reception sensitivity is a decisive factor in the coverage area, with -108 dBm, the optimal solution determined the use of three gateways to cover the smart campus area.

6.
Transpl Infect Dis ; 23(1): e13394, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32597550

RESUMO

From December 2019 to March 2020, China was the epicenter of the SARS-CoV-2 infection pandemic, but from that moment on, Europe surpassed China in the number of new cases and deaths related to this novel viral respiratory infection. The emergence of this world pandemic is particularly important for solid organ transplant recipients, who might have an increased risk of mortality, not only due to their chronic immunosuppression status, but also to the cardiovascular risk that correlates with several years of chronic kidney disease. To the extent that there is still a lack of knowledge about the clinical characteristics, evolution, and prognosis of SARS-CoV-2 infection in kidney transplant recipients, we will report the first 5 cases diagnosed and followed in our transplant unit, as well as share the therapeutic strategies adopted.


Assuntos
COVID-19/complicações , Transplante de Rim , SARS-CoV-2 , Transplantados , Adulto , Antibacterianos/uso terapêutico , Antimaláricos/uso terapêutico , COVID-19/patologia , Feminino , Humanos , Hidroxicloroquina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Esteroides/administração & dosagem , Esteroides/uso terapêutico , Tratamento Farmacológico da COVID-19
7.
J Org Chem ; 84(7): 3793-3800, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30753075

RESUMO

For the first time, 1,2-dimethyl-3-ethylimidazolium iodide (1a) catalyzes the ring opening of the bicyclic amidine system of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) or DBN (1,5-diazabicyclo[4.3.0]non-5-ene) on reaction with aldehydes. The mechanism here proposed involves an N-heterocyclic olefin (NHO) catalytic species that acts as a nucleophile to promote the cyclic amidine ring opening. The resulting ε-caprolactam- and γ-lactam-derived imines were obtained in moderate to excellent yields (28-99%) and reduced to the corresponding amines by sodium borohydride. Confirmation of the imine product was achieved via single-crystal X-ray diffraction studies.

8.
Photochem Photobiol Sci ; 16(4): 459-466, 2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28054064

RESUMO

fac-[Re(ampy)(CO)3(NN)]+ complexes (ampy = 2-aminomethylpyridine and NN = 1,10-phenanthroline (phen), and 2,2'-bipyridine (bpy)) were synthesized, purified and characterized by proton nuclear magnetic resonance (1H NMR), UV-visible and Fourier-transformed infrared (FT-IR) spectroscopies, and their photophysical properties were investigated using steady state and time-resolved emission spectroscopies. The electronic absorption spectra exhibit two main absorption bands: the higher energy band, which was assigned to intraligand transition (IL), and the lower energy band assigned to metal-to-ligand charge transfer (MLCT). Both complexes showed emission at room temperature in a CH3CN solution (λmax = 560 nm, ϕ = 0.091, τ = 560 ns for fac-[Re(ampy)(CO)3(phen)]+; λmax = 568 nm, ϕ = 0.024, τ = 100 ns for fac-[Re(ampy)(CO)3(bpy)]+) and rigid media (λmax = 530 nm, τ = 3300 ns for fac-[Re(ampy)(CO)3(phen)]+; λmax = 530 nm, τ = 853 ns for fac-[Re(ampy)(CO)3(bpy)]+) arising from the lowest lying 3MLCTRe→NN excited state. Both complexes along with fac-[Re(L)(CO)3(NN)]+/0 complexes, L = Cl or pyridine, were capable of efficiently photosensitizing the generation of singlet oxygen with quantum yield in the range of 0.59-0.28. These results highlight the potential application of fac-[Re(L)(CO)3(NN)]+/0 complexes in the development of sensitizers for the generation of singlet oxygen.

9.
Faraday Discuss ; 185: 361-79, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26395804

RESUMO

A multistate molecular dyad containing flavylium and viologen units was synthesized and the pH dependent thermodynamics of the network completely characterized by a variety of spectroscopic techniques such as NMR, UV-vis and stopped-flow. The flavylium cation is only stable at acidic pH values. Above pH ≈ 5 the hydration of the flavylium leads to the formation of the hemiketal followed by ring-opening tautomerization to give the cis-chalcone. Finally, this last species isomerizes to give the trans-chalcone. For the present system only the flavylium cation and the trans-chalcone species could be detected as being thermodynamically stable. The hemiketal and the cis-chalcone are kinetic intermediates with negligible concentrations at the equilibrium. All stable species of the network were found to form 1 : 1 and 2 : 1 host : guest complexes with cucurbit[7]uril (CB7) with association constants in the ranges 10(5)-10(8) M(-1) and 10(3)-10(4) M(-1), respectively. The 1 : 1 complexes were particularly interesting to devise pH responsive bistable pseudorotaxanes: at basic pH values (≈12) the flavylium cation interconverts into the deprotonated trans-chalcone in a few minutes and under these conditions the CB7 wheel was found to be located around the viologen unit. A decrease in pH to values around 1 regenerates the flavylium cation in seconds and the macrocycle is translocated to the middle of the axle. On the other hand, if the pH is decreased to 6, the deprotonated trans-chalcone is neutralized to give a metastable species that evolves to the thermodynamically stable flavylium cation in ca. 20 hours. By taking advantage of the pH-dependent kinetics of the trans-chalcone/flavylium interconversion, spatiotemporal control of the molecular organization in pseudorotaxane systems can be achieved.

10.
J Phys Chem A ; 119(4): 620-33, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-25569686

RESUMO

Primary alkyl amines are one of the most commonly used and effective reagents in CO2 capture. Most of the amines used for CO2 capture are recycled, but a minor portion of the amines are degraded after one electron oxidation process, leading to highly toxic substances. The combination of the complementary information obtained from photoinduced electron transfer (flash photolysis) and heterogeneous electron transfer (electrochemistry) appears to be very attractive to fully characterize the electron transfer reaction mechanism of reactive species in general, as well as for determining important thermodynamic properties, such as standard potentials (E°) or pKa values. It is particularly difficult to determine these crucial data accurately in the cases of alkyl primary amines. Hence, in this manuscript we focus on the establishment of the several alkyl primary amines oxidation mechanism in organic aprotic solvents. In order to achieve this, this work combines information provided by flash photolysis (nanosecond), cyclic voltammetry (millisecond), and digital simulation (nanomile-second). Moreover, the accuracy of the E° values calculated using the nanosecond equilibrium method allows not only revising them, but also estimating new important thermodynamic data concerning the bond dissociation energies (BDEs) of ammonium cations (N(+)-H) and of the amine cation radicals (α-C-H), as well as their corresponding pKa values.

11.
Tumour Biol ; 35(11): 11399-407, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25119587

RESUMO

Cervical cancer (CC) as other cancer types, presents molecular deregulations, such as the alterations of transcription factors. Krüppel-like factors (KLF) are a family of transcriptional regulators. They are involved in diverse cellular processes, such as proliferation, apoptosis, and angiogenesis among others. Here, we analyzed the expression of all 17 KLF members at messenger RNA (mRNA) level, and protein expression of the two most commonly altered KLF5 and KLF6 in cervical tissues. Fifty-nine cervical tissues ranging from normal tissue to CC were evaluated for KLF1-17 mRNA expression by end-point RT-PCR and KLF5 by qRT-PCR. For KLF5 and KLF6 protein analysis, a tissue microarray was constructed containing the 59 cases and subjected for immunohistochemistry assay and KLF6 IVS1-27G>A single nucleotide polymorphism by direct DNA sequencing. KLF2-16 expressions were present in normal tissue, whereas all 17 were present in Low-Grade Squamous Intraepithelial Lesion, High-Grade-SIL and CC, unrelated to presence of human papillomavirus (HPV). KLF5 mRNA expression gradually increased throughout the subgroups and overexpressed in CC (p=0.01). KLF5 and KLF6 proteins were immunodetected in all samples. For the KLF6 SNP analysis, 80% of the CC population analyzed presented GG genotype and the remaining 20% presented GA genotype (p=0.491). Our present data show that KLFs expression could not be related to HPV presence, at least at transcriptional level, and KLF5 mRNA overexpression could represent a potential molecular marker for CC; KLF6 SNP has no relation to increased risk of CC.


Assuntos
Adenocarcinoma/diagnóstico , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Neoplasias do Colo do Útero/diagnóstico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Colo do Útero/metabolismo , Colo do Útero/patologia , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Fator 6 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Adulto Jovem
12.
Access Microbiol ; 6(2): 000398, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482346

RESUMO

Bacillus pumilus (B. pumilus) is a ubiquitous spore-forming bacteria that has rarely been implicated in extraintestinal infections, mostly in immunocompromised hosts. The authors report a case of B. pumilus cellulitis with bacteremia in a person who injects drugs living with human immunodeficiency virus-hepatitis C virus (HIV-HCV) co-infection. Although similar cases have been reported for some species of the genus, namely Bacillus anthracis (B. anthracis) and Bacillus cereus (B. cereus), this case reinforces the importance of considering other Bacillus spp. as potential pathogens in skin and soft tissue infections and bloodstream infections related to intravenous drug use.

13.
Behav Sci (Basel) ; 14(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38667106

RESUMO

Research on the influence of chronotype and time of day (TOD) on cognitive performance, especially in children, is limited. We explored potential interactive effects, hypothesizing that performance differs when comparing preferred vs. non-preferred TOD. In total, 76 morning-type (MT = 37) or evening-type (ET = 39) children from the third and fourth grades (48.7% girls; M age = 8.05; SD age = 0.51), identified through the Children Chronotype Questionnaire, completed two 30-min neuropsychological assessment sessions via videoconference on the first (9:00) or last hour (16:00) of the school day. The protocol included neuropsychological tests targeting memory, language, and attention/executive domains. The results revealed an interactive effect of medium size between chronotype and TOD on a Rapid Alternating Stimulus (Naming) Task. MT and ET performed faster in asynchrony conditions (morning for ET; afternoon for MT). Additionally, ET outperformed MT in a Backward Digit Span Task, irrespective of TOD. TOD also influenced performance on an Alternating Verbal Fluency Task, with both MT and ET children performing better in the morning. These results underscore the importance of chronotype and TOD in children's cognitive performance, particularly in working memory and verbal fluency. Children assessed during non-preferred TOD exhibited better performance on some cognitive tasks, challenging the assumption that optimal times always yield superior results.

14.
Int J Antimicrob Agents ; : 107241, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38942247

RESUMO

BACKGROUND: Bacteroides fragilis is the most frequent cause of anaerobic bacteraemia. Although recent data suggest a rise in antimicrobial resistance (AMR) of this and other anaerobic bacteria, surveillance remains limited due to a lack of both data availability and comparability. However, a newly introduced standardised method for antimicrobial susceptibility testing (AST) of anaerobic bacteria has made larger scale surveillance possible for the first time. AIM: To investigate phenotypic AMR of Bacteroides fragilis isolates from bacteraemia across Europe in 2022. METHODS: In a multicentre approach, clinical microbiology laboratories in Europe were invited to contribute results of AST for Bacteroides fragilis blood culture isolates (including only the first isolate per patient and year). AST of a selection of four antibiotics was performed locally by participating laboratories in a prospective or retrospective manner, using the new EUCAST disc diffusion method on fastidious anaerobe agar (FAA-HB). RESULTS: A total of 16 European countries reported antimicrobial susceptibilities in 449 unique isolates of Bacteroides fragilis from blood cultures in 2022. Clindamycin demonstrated the highest resistance rates (20.9%, range 0 - 63.6%), followed by piperacillin-tazobactam (11.1%, 0 - 54.5%), meropenem (13.4%, 0 - 45.5%), and metronidazole (1.8%, 0 - 20.0%), all with wide variation between countries. CONCLUSION: Considering that the mean resistance rates across Europe were higher than expected for three of the four anti-anaerobic antibiotics under surveillance, both local AST of clinically relevant isolates of Bacteroides fragilis and continued surveillance on an international level is warranted.

15.
Radiol Case Rep ; 19(3): 1222-1227, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38259720

RESUMO

Hiatal hernia is a frequent pathology in the population; however, the most frequent hiatal hernia is type I, which accounts for up to 95% incidence, types II, III, and IV being less frequent and representing between 5% and 15%, and even less common are giant hernias. The definition of the giant hernia is still not exact in the literature; some authors define giant or massive hiatal hernia as one in which the hernia occupies more than 30% of the stomach and/or passes from other abdominal structures to the thorax. We describe the case of a patient with gastrointestinal symptomology without response to a proton pump inhibitor, with base exacerbation that required imaging studies, showing a large hernia defect passing to the thorax from abdominal organs (stomach, spleen, mesenteric fat), as well as alteration of the gastric and spleen axis with ascent in pancreatic body and tail, which corresponds to a giant hiatal hernia. Said pathology is very infrequent, with recurrences and postoperative complications. Our patient recovered from the surgical procedure with therapeutic success.

16.
Nanomaterials (Basel) ; 13(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37049299

RESUMO

Five Covalent Organic Frameworks (COFs) were synthesized and applied to Dye-Sensitized Solar Cells (DSSCs) as dyes and additives. These porous nanomaterials are based on cheap, abundant commercially available ionic dyes (thionin acetate RIO-43, Bismarck brown Y RIO-55 and pararosaniline hydrochloride RIO-70), and antibiotics (dapsone RIO-60) are used as building blocks. The reticular innovative organic framework RIO-60 is the most promising dye for DSSCs. It possesses a short-circuit current density (Jsc) of 1.00 mA/cm2, an open-circuit voltage (Voc) of 329 mV, a fill factor (FF) of 0.59, and a cell efficiency (η) of 0.19%. These values are higher than those previously reported for COFs in similar devices. This first approach using the RIO family provides a good perspective on its application in DSSCs as a dye or photoanode dye enhancer, helping to increase the cell's lifespan.

17.
IDCases ; 28: e01469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35308777

RESUMO

Rhodotorula mucilaginosa (R. mucilaginosa) has been increasingly recognized as an emerging opportunistic pathogen causing invasive fungal infection, mainly in immunosuppressed patients. We report the case of a previously undiagnosed lung cancer patient with a pleural empyema due to R. mucilaginosa.

18.
Nanomaterials (Basel) ; 12(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080024

RESUMO

The use of ionic liquid and organic salts as additives for electrolyte systems in dye-sensitized solar cells have been widely described in recent years. The tunability of their physical-chemical properties according to the cation-anion selection contributes toward their high efficiencies. For this purpose, several iodide-based organic salts including imidazolium, picolinium, guanidinium and alkylammonium cations were tested using acetonitrile/valeronitrile electrolytes and their photovoltaic parameters were compared. A best efficiency of 4.48% (4.15% for the reference) was found for 1-ethyl-2,3-dimethylimidazolium iodide ([C2DMIM]I) containing electrolyte, reaffirming the effectiveness of these additives. 4-tertbutylpyridine was included into the formulation to further improve the performance while determining which iodide salts demonstrate the highest synergy with this additive. [C2DMIM]I once again proved to be the superior additive, achieving an efficiency of 6.48% (6% for the reference). Electrochemical impedance spectroscopy was employed to elucidate the effects of the various additives, demonstrating the relevance of the counter electrode resistance on device performance. Finally, several computational descriptors for the cationic structures were calculated and correlated with the photovoltaic and resistance parameters, showing that properties related to polarity, namely relative positive charge, molecular polarizability and partition coefficient are in good agreement with the counter-electrode resistance.

19.
Microbiol Spectr ; 10(5): e0292722, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36043877

RESUMO

Imipenem-relebactam is a novel ß-lactam-ß-lactamase inhibitor combination. We evaluated the in vitro activity of imipenem-relebactam and comparators against Enterobacterales clinical isolates recovered in 8 Spanish and 11 Portuguese intensive care units (ICUs) (SUPERIOR, 2016-2017; STEP, 2017-2018). Overall, 747 Enterobacterales isolates (378 Escherichia coli, 252 Klebsiella spp., 64 Enterobacter spp., and 53 other species) were prospectively collected from ICU patients with complicated intraabdominal (cIAI), complicated urinary tract (cUTI), and lower respiratory tract (LRTI) infections. MICs were determined (ISO-broth microdilution), and whole-genome sequencing (WGS) was performed in a subset of isolates displaying susceptible and resistant imipenem-relebactam MICs. Imipenem-relebactam (98.7% susceptible) showed similar activity to ceftazidime-avibactam (99.5% susceptible) and higher than ceftolozane-tazobactam (86.9% susceptible). Imipenem-relebactam was inactive against 1.3% (10/747) isolates, all of them due to carbapenemase production (9 K. pneumoniae and 1 E. cloacae). Imipenem-relebactam was active against 100% of extended-spectrum ß-lactamase (ESBL)-E. coli and ESBL-Klebsiella spp. isolates and 80.4% of carbapenemase-Klebsiella spp. producers. Carbapenemase genes were confirmed by WGS in 41 Klebsiella spp.: OXA-48 (20/41), KPC-3 (14/41), OXA-181 (4/41), NDM-1 (1/41), OXA-48 + VIM-2 (1/41), and KPC-3 + VIM-2 (1/41). In Klebsiella spp. isolates, relebactam restored imipenem susceptibility in all KPC-3 producers, and resistant isolates (7/41) were mostly OXA-48 + CTX-M-15-K. pneumoniae high-risk clones (7/9). Intercountry differences were detected as follows: OXA-48 (17/21) was dominant in Spain, unlike KPC-3 (14/15) in Portugal. Imipenem-relebactam was 100% active against CTX-M-15-ST131-H30Rx-E. coli high-risk clone, predominant in both countries. Our results depict the potential role of imipenem-relebactam in ICU patients with cIAIs, cUTIs, and LRTIs due to wild-type ESBL- and carbapenemase-producing Enterobacterales, particularly KPC producers. IMPORTANCE We comparatively evaluate the in vitro activity of a drug combination consisting of a carbapenem (imipenem) and a novel inhibitor of beta-lactamases (relebactam), a mechanism that destroys beta-lactam antibiotics. We assess the activity against a collection of Enterobacterales clinical isolates recovered from difficult-to-treat infections in patients admitted to different intensive care units in Portugal and Spain. Imipenem-relebactam shows excellent activity in avoiding common resistance mechanisms in this setting, such as extended-spectrum beta-lactamases and carbapenemases widely distributed, including KPCs. We show few resistant isolates (<2%). Molecular characterization by whole-genome sequencing shows that most of the resistant isolates produced specific carbapenemase, such as OXA-48 or metalo-betalactamases. Our study updates the activity of imipenem-relebactam in light of current epidemiology in a hospital setting in which the use of this combination is needed due to the presence of infections due to multidrug-resistant isolates.


Assuntos
Escherichia coli , Inibidores de beta-Lactamases , Humanos , Inibidores de beta-Lactamases/farmacologia , Portugal , Escherichia coli/genética , Espanha , Antibacterianos/farmacologia , Imipenem/farmacologia , Tazobactam/farmacologia , beta-Lactamases/genética , Testes de Sensibilidade Microbiana , Klebsiella pneumoniae/genética , Combinação de Medicamentos , Unidades de Terapia Intensiva
20.
Chem Commun (Camb) ; 56(94): 14893-14896, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33179658

RESUMO

Developing organic semiconductors for organic thin film transistors (OTFT) and optoelectronic applications is a challenge. We developed highly crystalline pentacyclic diimides (3) and (4) which showed good OTFT and OLED potential and energy gaps of 2.60 eV and 2.54 eV. They exhibited interesting photo and eletroluminescence activity. Both compounds showed good quantum yields (0.56 for (3) and 0.60 for (4)).

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