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1.
Nurse Educ Pract ; 78: 104038, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38936299

RESUMEN

AIM: This study explores and describes the second victim phenomenon in nursing students in association with the characteristics of the clinical learning environment and the clinical supervision process. DESIGN: Qualitative design using conventional content analysis and summative content analysis approaches. METHODS: From September 2022 to July 2023, in-depth semi-structured individual interviews were conducted with a purposive sample of 10 undergraduate nursing students. RESULTS: Six main themes were developed: 'defining the physical and psychological responses after the most significant patient safety incident', 'analyzing the characteristics of patient safety incidents', 'creating a safe learning environment to provide the best care for patients', 'developing mentorship capabilities and qualities for an ideal follow up of students as a second victim', 'providing resources and integrating support structures to second victim nursing students during their clinical learning', and 'considering the cooperation and coordination between the health institution and the higher education institutions.' CONCLUSION: Nursing students become second victims during their clinical placement. The clinical learning environment and mentoring characteristics influence the second victim experience.

2.
Lancet Reg Health Am ; 36: 100804, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38912329

RESUMEN

Background: Since 2014, Brazil has gradually implemented the Xpert MTB/RIF (Xpert) test to enhance early tuberculosis (TB) and drug-resistant (DR-TB) detection and control, yet its nationwide impact remains underexplored. Our study conducts an intervention time-series analysis (ITSA) to evaluate how the Xpert's implementation has improved TB and DR-TB detection nationwide. Methods: 1,061,776 cases from Brazil's National TB Registry (2011-2022) were reviewed and ITSA (2011-2019) was used to gauge the impact of the Xpert's adoption on TB and DR-TB notification. Granger Causality and dynamic regression modelling determined if incorporating Xpert testing as an external regressor enhanced forecasting accuracy for Brazil's future TB trends. Findings: Xpert implementation resulted in a 9.7% increase in TB notification and substantial improvements in DR-TB (63.6%) and drug-susceptible TB (92.1%) detection compared to expected notifications if it had not been implemented. Xpert testing counts also presented a time-dependent relationship with DR-TB detection post-implementation, and improved predictions in forecasting models, which depicted a potential increase in TB and DR-TB detection in the next six years. Interpretation: This study underscores the critical role of Xpert's adoption in boosting TB and DR-TB detection in Brazil, reinforcing the case for its widespread use in disease control. Improvements in prediction accuracy resulting from integrating Xpert data are crucial for allocating resources and reducing the incidence of TB. By acknowledging Xpert's role in both disease control and improving predictions, we advocate for its expanded use and further research into advanced molecular diagnostics for effective TB and DR-TB control. Funding: FIOCRUZ.

3.
Bioorg Chem ; 150: 107555, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38885548

RESUMEN

The conventional approach to developing light-sensitive glycosidase activity regulators, involving the combination of a glycomimetic moiety and a photoactive azobenzene module, results in conjugates with differences in glycosidase inhibitory activity between the interchangeable E and Z-isomers at the azo group that are generally below one-order of magnitude. In this study, we have exploited the chemical mimic character of sp2-iminosugars to access photoswitchable p- and o-azobenzene α-O-glycosides based on the gluco-configured representative ONJ. Notably, we achieved remarkably high switching factors for glycosidase inhibition, favoring either the E- or Z-isomer depending on the aglycone structure. Our data also indicate a correlation between the isomeric state of the azobenzene module and the selectivity towards α- and ß-glucosidase isoenzymes. The most effective derivative reached over a 103-fold higher inhibitory potency towards human ß-glucocerebrosidase in the Z as compared with the E isomeric form. This sharp contrast is compatible with ex-vivo activation and programmed self-deactivation at physiological temperatures, positioning it as a prime candidate for pharmacological chaperone therapy in Gaucher disease. Additionally, our results illustrate that chemical tailoring enables the engineering of photocommutators with the ability to toggle inhibition between α- and ß-glucosidase enzymes in a reversible manner, thus expanding the versatility and potential therapeutic applications of this approach.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38912571

RESUMEN

INTRODUCTION: Digital microscopy transformation, the basis for the virtual microscopy applications, is a challenge but also a requirement in modern Medical Education. This paper presents the scope, background, methods, and results of the project "Digital Transformation of Histology and Histopathology by Virtual Microscopy (VM) for an Innovative Medical School Curriculum", VM3.0, funded by the European Union under the Erasmus+ framework (ref.no.2022-1-RO01-KA220-HED-000089017). The project was initiated at Grigore T. Popa University of Medicine and Pharmacy, Iași, Romania, with the support of Euroed Foundation, Iași, and cooperation of University partners from Gdansk (Poland), Plovdiv (Bulgaria), Alicante (Spain), and Patras (Greece) aimed to implement digital histology and histopathology teaching in a common network. MATERIALS AND METHODS: The backbone of the project was the development of a Digital Slide Platform based on the scans of histological slides collected from all the partners of the participating universities and the creation of a simple and fast digital/internet communication tool that could be used to improve histology and histopathology teaching of medical and natural sciences students. The construction of a Virtual Microscopy Library (VML) has been based on the acquisition of whole scans of high-quality histological slides stained by hematoxylin and eosin (H&E) and other classical staining methods and description of the details in English as well as respective languages of the project's partners. The VML can be used for different approches, both for students' instruction in classes as well as for individual students' work and self-testing. Universities from other countries could use the modal structure of the developed VML system on the condition that more slides are provided and the implementation of national language(s) is implemented. CONCLUSIONS: The combined efforts of all university partners allowed to establish the dynamic low-cost virtual microscopy educational system. The VM system could help unify the standards of cytology, histology, and histopathology teaching in a quest for the digital transformation of the European educational system.

5.
Curr Probl Cardiol ; 49(9): 102691, 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38857665

RESUMEN

Hypertrophic cardiomyopathy (HCM) with left ventricular outflow tract obstruction that doesn't improve with pharmacological management often requires septal myectomy. However, there are few centers with experience in the practice of this procedure in our country. We describe the clinical and echocardiographic characteristics and postoperative outcomes of patients with HCM indicated for septal myectomy at a reference center in Colombia. MATERIALS AND METHODS: Retrospective cohort study. Patients undergoing septal myectomy between 2010 and 2023 were included. Data were collected before and two years after surgery. RESULTS: 18 patients were included. The mean age was 50 years. The predominant functional class was NYHA II/III (94 %). Asymmetric septal variant (83.3 %) was the most frequent as well as obstructive phenotype (88.8 %). After myectomy, 70.5 % improved to NYHA I and 62.4 % had no significant gradient (<30 mmHg), and the most of patient improved SAM. One patient died post-procedure, anymore complications were presented. DISCUSSION/CONCLUSIONS: Septal myectomy is a safe procedure, with clinical and echocardiographic improvement, with low complication rates.

7.
BMC Public Health ; 24(1): 1385, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783264

RESUMEN

BACKGROUND: Identifying patients at increased risk of loss to follow-up (LTFU) is key to developing strategies to optimize the clinical management of tuberculosis (TB). The use of national registry data in prediction models may be a useful tool to inform healthcare workers about risk of LTFU. Here we developed a score to predict the risk of LTFU during anti-TB treatment (ATT) in a nationwide cohort of cases using clinical data reported to the Brazilian Notifiable Disease Information System (SINAN). METHODS: We performed a retrospective study of all TB cases reported to SINAN between 2015 and 2022; excluding children (< 18 years-old), vulnerable groups or drug-resistant TB. For the score, data before treatment initiation were used. We trained and internally validated three different prediction scoring systems, based on Logistic Regression, Random Forest, and Light Gradient Boosting. Before applying our models we splitted our data into training (~ 80% data) and test (~ 20%) sets, and then compared the model metrics using the test data set. RESULTS: Of the 243,726 cases included, 41,373 experienced LTFU whereas 202,353 were successfully treated. The groups were different with regards to several clinical and sociodemographic characteristics. The directly observed treatment (DOT) was unbalanced between the groups with lower prevalence in those who were LTFU. Three models were developed to predict LTFU using 8 features (prior TB, drug use, age, sex, HIV infection and schooling level) with different score composition approaches. Those prediction scoring systems exhibited an area under the curve (AUC) ranging between 0.71 and 0.72. The Light Gradient Boosting technique resulted in the best prediction performance, weighting specificity and sensitivity. A user-friendly web calculator app was developed ( https://tbprediction.herokuapp.com/ ) to facilitate implementation. CONCLUSIONS: Our nationwide risk score predicts the risk of LTFU during ATT in Brazilian adults prior to treatment commencement utilizing schooling level, sex, age, prior TB status, and substance use (drug, alcohol, and/or tobacco). This is a potential tool to assist in decision-making strategies to guide resource allocation, DOT indications, and improve TB treatment adherence.


Asunto(s)
Perdida de Seguimiento , Aprendizaje Automático , Sistema de Registros , Tuberculosis , Humanos , Masculino , Femenino , Estudios Retrospectivos , Adulto , Brasil/epidemiología , Persona de Mediana Edad , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Adulto Joven , Antituberculosos/uso terapéutico , Adolescente , Algoritmos
8.
Artículo en Inglés | MEDLINE | ID: mdl-38615255

RESUMEN

BACKGROUND: The present systematic review aims to investigate the guidelines for prescribing Preventive Antibiotic Therapy (PAT) in the placement of dental implants (DIs) without anatomical constraints in healthy patients by clinicians in Europe and to compare them with current recommendations. MATERIAL AND METHODS: A search was performed in 4 databases: Medline (via PubMed), Web of Science, Scopus, and LILACS. The criteria employed were those described in the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) declaration (PROSPERO Registration number: CRD42022382278). RESULTS: The electronic search identified 10 studies published between 2010 and 2023 that met the established criteria. Overall, 60.8% ± 24.1% of European professionals routinely prescribe PAT, with the most frequent regimen being perioperative (mean= 46.7% ± 24.3%), followed by postoperative PAT only (mean= 20.3% ± 9.7%). CONCLUSIONS: The most commonly prescribed antibiotic both pre- and postoperatively is amoxicillin and, in allergic patients, clindamycin. In Europe, more doses of PAT are being prescribed than suggested by current recommendations. For this reason, more PAT education is needed in educational curricula to promote a more rational use of antibiotics to reduce the occurrence of antimicrobial resistance.

9.
J Multidiscip Healthc ; 17: 1385-1400, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560485

RESUMEN

Timely and effective prehospital care significantly impacts patient outcomes. Paramedics, as the frontline providers of emergency medical services, are entrusted with a range of critical responsibilities aimed at safeguarding the well-being of patients from the moment they initiate contact in the out-of-hospital environment to the time of handover at healthcare facilities. This study aimed to understand the multifaceted roles of paramedics in promoting patient safety within the context of prehospital emergency medical services. A systematic review with an integrative approach using the Whittemore and Knafl's framework was performed examining qualitative, quantitative, and mixed-methods research, then conducting data assessment, quality appraisal, and narrative research synthesis. Literature search encompassed PubMed (including MEDLINE), Scopus, Cinahl, ProQuest, Web of Science, and EMBASE, with the aim of retrieving studies published in English in the last decade from 2013 to 2023. To conceptualize the roles of paramedics in ensuring patient safety, the review findings were reflected to and analyzed through the role theory. The preliminary exploration of the database yielded 2397 studies, ultimately narrowing down to a final selection of 16 studies for in-depth data analysis and research synthesis. The review findings explored facilitators and obstacles faced by paramedics in maintaining patient safety in terms of role ambiguity, role conflict, role overload, role identity, and role insufficiency in the dynamic nature of prehospital care. It also highlighted the diverse roles of paramedics in ensuring patient safety, which encompassed effective communication and decision making for the appropriate management of life-threatening emergencies. The effectiveness of paramedics in playing their roles in promoting patient safety relies on acknowledging the contributions of paramedics to the culture of patient safety; training and educational initiatives focused on enhancing their decision-making abilities and both their non-technical and technical competencies; developing relevant guidelines and protocols; improving collaboration between paramedics and other healthcare peers; optimizing environmental conditions and equipment; fostering a supportive work environment.

10.
Dalton Trans ; 53(18): 7788-7800, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38623699

RESUMEN

We describe the mononuclear anionic cyanido-pentafluorophenyl complexes, (NBu4)[Pt(C^N)(C6F5)(CN)] [C^N = 7,8-benzoquinolate (bzq) 1, 2-(2,4-difluorophenyl)pyridinate (dfppy) 2] and the heteropolynuclear derivatives [{Pt(C^N)(C6F5)(CN)}Tl] (C^N = bzq 3, dfppy 4). These complexes were synthesized via a two-step modular synthesis by reaction of the corresponding potassium salts K[Pt(C^N)(C6F5)(CN)], prepared in situ from [Pt(C^N)(C6F5)(DMSO)] and KCN in acetone/H2O, with TlPF6. The structures of {[Pt(bzq)(C6F5)(CN)Tl]·THF}n (3·THF)n and [{Pt(dfppy)(C6F5)(CN)}Tl]4·dioxane [4]4·dioxane, determined by X-ray crystallography, confirm the presence of Pt(II)-Tl(I) bonds [2.9795(6)-3.0736(3) Å], but in the dfppy complex, the incorporation of dioxane, causes a significant structural change. Thus, whereas [3·THF]n achieves a bent-ladder shape extended double chain Tl⋯[Pt⋯Tl]n⋯Pt supported by lateral bridging [Pt](µ-CN)[Tl] ligands, [4]4·dioxane is formed by discrete Pt4Tl4 rectangular aggregates stabilized by [Pt](µ-CN)[Tl] and Pt⋯Tl bonds, which are connected by dioxane bridging molecules through Tl⋯O(dioxane) additional contacts. Solid state emissions are redshifted compared with the mononuclear derivatives 1 and 2 and have been assigned, with the support of theoretical calculations on Pt4Tl4 models, to metal-metal'-to-ligand charge transfer (3MM'LCT [d/s σ*(Pt, Tl) → π*(C^N)]) for 3 and mixed 3MM'LCT/3IL for 4. In fluid THF solution, the complexes are not emissive. At 77 K, 3 and 4 exhibit bright emissions attributed to the formation of bimetallic [{Pt(C^N)(C6F5)(CN)}Tl(THF)x], and anionic [Pt(C^N)(C6F5)(CN)]- fragments. Furthermore, both 3 and 4 exhibit a reversible mechanochromism with a red shift of the emissions upon crushing, suggesting some degree of shortening of metal-metal separation. Finally, complex 3 shows solvatochromic behavior with color/luminescence changes by treatment with a drop of MeOH, CH2Cl2, THF or Et2O, with shifts from 583 in 3-MeOH to 639 nm in 3-THF. However, 4 only demonstrates a bathochromic response to MeOH.

12.
Photodiagnosis Photodyn Ther ; 46: 104031, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38438001

RESUMEN

BACKGROUND: Daylight photodynamic therapy (DL-PDT) has become one of the most effective treatments for the resolution of actinic keratosis (AK) of Olsen grade 1 and 2. Generally, PDT it is carried out in a clinic setting, which involves the patient's and their caregivers commuting to the hospital as well as a significant use of resources to carry it out within the clinic setting. OBJECTIVES: To determine the efficacy and safety of a home-based treatment of AK with DL-PDT with the BF-200 ALA gel compared to a clinic-based setting. METHODS: The study was performed as a randomized, single-center, non-inferiority clinical trial with two parallel groups. 9 patients received one clinic-based DL-PDT (group 1) and 11 patients received one session of home-based DL-PDT (group 2). The primary endpoints were the mean AK clearance per patient and the total AK lesion clearance rate 12 weeks after treatment. The secondary endpoints were the number of remaining AKs and new AKs appearing in the treatment field 12 weeks after one PDT session. The pain during and 24 h after PDT as well as the local skin reactions were also assessed. RESULTS: The overall reduction of AK lesions per patient was similar in both groups with one PDT session. An overall AK clearance per patient of 10 ± 4.33 for group 1 versus 9.73 ± 2.9 for group 2 without statistically significant differences (p = 0.868). Regarding the clearance rate, although it was slightly higher in group 2 (71.58 ± 22.51 vs 82.1 ± 11.13), the analysis did not show statistically significant differences. The mild pain recorded during the treatment course and the mild local skin reactions were similar in both groups. Patient satisfaction was high for both groups without statistically significant differences. CONCLUSION: Self-performed home-based DL-PDT with BF-200 ALA gel is as effective as the one performed in a clinic-based setting, with a comparable safety profile, high levels of patient satisfaction and with advantages for the patients and their caregivers that can enhance patient´s adherence to the treatment.


Asunto(s)
Ácido Aminolevulínico , Queratosis Actínica , Fotoquimioterapia , Fármacos Fotosensibilizantes , Humanos , Queratosis Actínica/tratamiento farmacológico , Ácido Aminolevulínico/uso terapéutico , Ácido Aminolevulínico/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico , Masculino , Femenino , Estudios Prospectivos , Anciano , Persona de Mediana Edad , Método Simple Ciego , Anciano de 80 o más Años , Emulsiones
13.
Semergen ; 50(5): 102198, 2024.
Artículo en Español | MEDLINE | ID: mdl-38507828

RESUMEN

INTRODUCTION: Currently there is a shortage of general practitioners (GP), and this is expected to increase in the coming years. Despite this need, it is a specialty that is supposedly little demanded, leaving specialized training places unfilled in recent years. The purpose of this study is to present new parameters to more objectively measure the demand and the relationship between supply and demand. METHODS: A database was used with the results of the places assigned in the MIR calls from 2002 to 2023. The calculated parameters were quoting index (CI), quote order, the order of top demand and the order of total demand of the GP specialty. The software R version 4.3.02 was used for statistical analysis. RESULTS: The specialty quotation and top demand have remained constant during the study period, while there has been a slight and progressive worsening of the total demand. Nevertheless, the total demand for Family Medicine in the last call for MIR exam was higher than that for specialties such as urology, neurology, ENT, endocrinology, oncology, intensive care medicine or neurosurgery, among others. CONCLUSIONS: In contrast to the subjective perception of the worsening attractiveness Family Medicine in the last MIR calls, using objective parameters, we found that the attractiveness of the specialty, measured as quotation (supply/demand ratio) and demand, has remained stable (with a slight worsening of total demand).


Asunto(s)
Medicina Comunitaria , Medicina Familiar y Comunitaria , Humanos , Especialización , España , Selección de Profesión , Médicos Generales/estadística & datos numéricos , Médicos Generales/organización & administración , Medicina , Necesidades y Demandas de Servicios de Salud , Bases de Datos Factuales
14.
Artículo en Inglés | MEDLINE | ID: mdl-38538431

RESUMEN

INTRODUCTION: The evaluation of blood pressure (BP) is essential in the acute phase of stroke. Although ambulatory blood pressure monitoring (ABPM) is a validated method for BP control, there are few studies assessing the usefulness of ABPM in the acute phase of stroke. DEVELOPMENT: A systematic review was carried out according to the PRISMA criteria in the PubMed/Medline and Scopus databases. Those articles that analysed the use of ABPM in the first days after suffering a stroke from 1992 to 2022 were selected. Those articles focused on the post-acute or sequelae phase of the stroke, with a sample size of less than 20 and those where the primary objective was different from the defined one. A total of 28 articles were included. CONCLUSIONS: The use of ABPM in patients with recent stroke demonstrates that the normal circadian profile of BP is altered in more than two-thirds of patients and that this will be fundamentally conditioned by the haemodynamic changes that occur on autoregulation of cerebral blood flow, the type of stroke or the response to treatment. Furthermore, these changes in BP have prognostic implications and are correlated with functional status, stroke recurrence and mortality, among others. However, although they continue to be a growing area of research, new studies are needed to clarify the real role of this technique in patients with acute stroke.

15.
Rev Esp Anestesiol Reanim (Engl Ed) ; 71(4): 317-323, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38354774

RESUMEN

Neuraxial anesthesia in patients with cerebrospinal fluid (CSF) shunt devices has traditionally been associated with a high risk of complications. In order to gather all available evidence, a structured search was conducted to include published studies involving users of these devices, undergoing any form of neuraxial technique for obstetric or surgical procedures unrelated to them. Effectiveness of the technique and perioperative complications were assessed. Only case series and case reports (n = 72) were identified. One patient was found to have insufficient anesthetic coverage, necessitating a modification of the technique, and another one had an intraoperative complication which compromised the subject's safety. No infection events or postoperative device dysfunction related to the anesthetic method were described. The evidence found is scarce and of low quality, preventing the establishment of significant conclusions. Nevertheless, patients may obtain benefit from an individualized evaluation.


Asunto(s)
Derivaciones del Líquido Cefalorraquídeo , Humanos , Derivaciones del Líquido Cefalorraquídeo/efectos adversos , Femenino , Anestesia Epidural/métodos , Anestesia Epidural/efectos adversos , Anestesia Raquidea/métodos , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Embarazo
16.
Actas Urol Esp (Engl Ed) ; 48(4): 304-310, 2024 May.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38373481

RESUMEN

INTRODUCTION: Prostatic carcinoma (PC) is a frequent neoplasm in elderly patients. Although androgen deprivation is associated with survival benefits, it is also related to adverse effects such as osteoporosis, frailty, or sarcopenia, which can negatively affect the patient's quality of life. This study aims to quantify and evaluate the prevalence of osteoporosis, frailty, or sarcopenia in elderly PC patients before and after androgen deprivation. We present data from an interim analysis. MATERIALS AND METHODS: PROSARC is a national (Spain) prospective observational study (May-2022-May-2025) still in progress in 2 hospitals. It includes patients with high-risk PC, aged ≥70 years, non-candidates for local treatment and scheduled to start androgen deprivation therapy. The following variables are analyzed: comorbidity, frailty (Fried frailty phenotype criteria), osteoporosis, sarcopenia (EWGSOP2), fat mass and muscle mass, before treatment and after 6 months of follow-up. RESULTS: A 6-month follow-up was completed by 12/25 included patients (mean age, 84 years), with a high baseline prevalence of pre-frailty/frailty (67.7%), sarcopenia (66.7%) and osteoporosis (25%). Treatment did not significantly alter these variables or comorbidity. We observed changes in body mass index (p=0.666), decreased mean value of appendicular muscle mass (p=0.01) and increased percentage of fat mass (p=0.012). CONCLUSION: In patients with high-risk PC, advanced age and a considerable prevalence of osteoporosis, frailty and sarcopenia, androgen deprivation (ADT; 6 months) produces decreased muscle mass without impact on the incidence of the known adverse effects of androgen deprivation.


Asunto(s)
Antagonistas de Andrógenos , Osteoporosis , Neoplasias de la Próstata , Sarcopenia , Masculino , Humanos , Antagonistas de Andrógenos/efectos adversos , Antagonistas de Andrógenos/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Estudios Prospectivos , Anciano de 80 o más Años , Anciano , Sarcopenia/epidemiología , Sarcopenia/inducido químicamente , Osteoporosis/inducido químicamente , Osteoporosis/epidemiología , Prevalencia , Medición de Riesgo , Fragilidad/epidemiología , Fragilidad/inducido químicamente
17.
Inorg Chem ; 63(3): 1589-1606, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38247362

RESUMEN

Based on 2-phenylbenzothiazole (pbt) and 2-(4-dimethylaminophenyl)benzothiazole (Me2N-pbt), mononuclear [Pt(pbt)(R'2-pzH)2]PF6 (R'2-pzH = pzH 1a, 3,5-Me2pzH 1b, 3,5-iPr2pzH 1c) and diplatinum (PtII-PtII) [Pt(pbt)(µ-R'2pz)]2 (R'2-pz = pz 2a, 3,5-Me2pz 2b, 3,5-iPr2pz 2c) and [Pt(Me2N-pbt)(µ-pz)]2 (3a) complexes have been prepared. In the presence of sunlight, 2a and 3a evolve, in CHCl3 solution, to form the PtIII-PtIII complexes [Pt(R-pbt)(µ-pz)Cl]2 (R = H 4a, NMe2 5a). Experimental and computational studies reveal the negligible influence of the pyrazole or pyrazolate ligands on the optical properties of 1a-c and 2a,b, which exhibit a typical 3IL/3MLCT emission, whereas in 2c the emission has some 3MMLCT contribution. 3a displays unusual dual, fluorescence (1ILCT or 1MLCT/1LC), and phosphorescence (3ILCT) emissions depending on the excitation wavelength. The phosphorescence is lost in aerated solutions due to sensitization of 3O2 and formation of 1O2, whose determined quantum yield is also wavelength dependent. The phosphorescence can be reversibly photoinduced (365 nm, ∼ 15 min) in oxygenated THF and DMSO solutions. In 4a and 5a, the lowest electronic transitions (S1-S3) have mixed characters (LMMCT/LXCT/L'XCT 4a and LMMCT/LXCT/ILCT 5a) and they are weakly emissive in rigid media. The 1O2 generation property of complex 3a is successfully used for the photooxidation of p-bromothioanisol showing its potential application toward photocatalysis.

18.
Anal Chem ; 96(2): 615-619, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38165272

RESUMEN

STD NMR spectroscopy is a powerful ligand-observed NMR tool for screening and characterizing the interactions of small molecules and low molecular weight fragments with a given macromolecule, identifying the main intermolecular contacts in the bound state. It is also a powerful analytical technique for the accurate determination of protein-ligand dissociation constants (KD) of medium-to-weak affinity, of interest in the pharmaceutical industry. However, accurate KD determination and epitope mapping requires a long series of experiments at increasing saturation times to carry out a full analysis using the so-called STD NMR build-up curve approach and apply the "initial slopes approximation". Here, we have developed a new protocol to bypass this important limitation, which allows us to obtain initial slopes by using just two saturation times and, hence, to very quickly determine precise protein-ligand dissociation constants by STD NMR.


Asunto(s)
Imagen por Resonancia Magnética , Proteínas , Ligandos , Proteínas/química , Espectroscopía de Resonancia Magnética/métodos , Mapeo Epitopo , Unión Proteica
19.
J Agric Food Chem ; 72(4): 1959-1968, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37129181

RESUMEN

Oak wood is the main material used by coopers to manufacture casks for the aging of spirits or wines. Phenolic compounds are the main components extracted from the wood during spirit aging. In the present study, a chemometric approach based on unsupervised (PCA) and supervised (PLS-DA) pattern recognition techniques has been applied to the chromatographic instrumental fingerprints, obtained by ultra-high-performance liquid chromatography (UHPLC) at 280 nm, of the phenolic profiles of brandies aged in casks made of different oak wood species. The resulting natural data groupings and the PLS-DA models have revealed that the oak wood species, the toasting level, and the aging time are the most influential factors on the phenolic profile of the final products. Fingerprinting should be considered as a very useful feature, as it represents a considerable advantage, in terms of internal and quality control, for brandy producers.


Asunto(s)
Quercus , Vino , Cromatografía Líquida de Alta Presión , Quercus/química , Quimiometría , Bebidas Alcohólicas/análisis , Vino/análisis , Fenoles/química , Madera/química
20.
Microb Biotechnol ; 17(1): e14357, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38151853

RESUMEN

Expanded graphite (EG) electrodes gather several advantages for their utilization in microbial electrochemical technologies (MET). Unfortunately, the low microbial electroactivity makes them non-practical for implementing them as electrodes. The objective of this work is to explore the enhancement of microbial electroactivity of expanded graphite (commercial PV15) through the generation of nanopores by CO2 treatment. The changes in properties were thoroughly analysed by TG, XRD, Raman, XPS, gas adsorption, SEM and AFM, as well as microbial electroactivity in the presence of Geobacter sulfurreducens. Nanopores remarkably enhance the microbially derived electrical current (60-fold increase). Given the inaccessibility of micron-sized bacteria to these nanopores, it is suggested that the electric charge exchanged by electroactive microorganisms might be greatly affected by the capability of the electrode to compensate these charges through ion adsorption. The increased microbial current density produced on activated PV15 opens the possibility of using such materials as promising electrodes in MET.


Asunto(s)
Fuentes de Energía Bioeléctrica , Geobacter , Grafito , Grafito/química , Porosidad , Biopelículas , Geobacter/química , Electrodos
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