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1.
Int J Sports Med ; 45(7): 526-531, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38346702

RESUMO

Groin problems are common in multidirectional sports. The aim of the present study is to assess seasonal, current, and trends for groin problems in rink hockey players, irrespective of their playing position, age, or gender. Rink hockey players from three countries [n=446 (162 female, 284 male)] were invited to participate in an online questionnaire. This form evaluated the prevalence of groin problems (time-loss and non-time-loss) for the 2022-2023 season, as well as monthly prevalence of groin problems (time-loss and non-time-loss). All groin problems were compared between playing position, gender, and age to assess between-group differences. Senior males reported the highest time-loss (25%) and non-time-loss (51%) for seasonal prevalence; while U-17 males reported the lowest in both categories of groin problems (time-loss 9%, non-time-loss 27%). No significant differences between playing position or gender were found for any of the groin problems analyzed. In-season prevalence (9-15.7%) of groin problems was significantly higher than pre-season (7.4%) prevalence (p<0.01). Seasonal prevalence of groin problems is common in rink hockey, regardless of gender, playing position, or age. Preventive efforts should be directed towards all players, regardless of their individual characteristics.


Assuntos
Virilha , Hóquei , Estações do Ano , Humanos , Masculino , Hóquei/lesões , Prevalência , Feminino , Adulto , Adulto Jovem , Adolescente , Inquéritos e Questionários , Fatores Etários , Traumatismos em Atletas/epidemiologia , Fatores Sexuais
2.
J Clin Ultrasound ; 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39279273

RESUMO

PURPOSE: The aim of this study was to describe in volunteers and cadavers the location of the vascular structures at risk for performing a new safe and effective ultra-minimally invasive ultrasound guided long head of the biceps tendon (LHBT) release. METHODS: First, with Doppler ultrasound, we defined the position of the acromial artery from our distal cutting point, on the posterior margin of the LHBT. Second, we performed an ultra-minimally invasive ultrasound guided LHBT release in cadavers. We described the stump and reported safety (no rotator cuff, vascular, or articular damages) and efficacy (tendon release rate). RESULTS: In 20 volunteers, the mean distance from the distal cutting point to the acromial artery was 0.9 ± 0.1 cm (range, 0.3-1.6). Ultra-minimally invasive LHBT release was safe and fully effective in the eight specimens. The proximal stump measured a mean of 2.8 cm (range, 1.9-4). There were no complications. CONCLUSIONS: A safe and effective ultra-minimally invasive ultrasound guided LHBT release in cadavers is feasible through an anterior approach.

3.
Acta Radiol ; 64(3): 1078-1085, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35607260

RESUMO

BACKGROUND: Meniscal ramp lesions have gained much prominence in recent years due to a significant increase in their diagnosis and their important biomechanical involvement in the knee. A new proposed classification of these lesions has recently been published. PURPOSE: To evaluate the reproducibility of the new classification of meniscal ramp lesions recently published using magnetic resonance imaging (MRI). MATERIAL AND METHODS: A total of 249 post-traumatic knee MRI studies were evaluated by three musculoskeletal radiologists independently. Patients with an anterior cruciate ligament (ACL) tear on MRI in addition to a recent history of trauma to the knee for <12 months were included in the study, for a total of 95. We carried out an inter-observer concordance study to analyze whether the new classification is reproducible to detect meniscal ramp lesions and to classify them into their different types. RESULTS: Among our study cohort of 95 patients, we found 47 (49.5%) ramp lesions. In the inter-observer study, we obtained a good concordance (k = 0.733) in the detection of these lesions and an excellent one (k = 0.843) when the type of lesion is described. CONCLUSION: This study demonstrates that the new classification of meniscal ramp lesions has good reproducibility on MRI.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Humanos , Reprodutibilidade dos Testes , Reconstrução do Ligamento Cruzado Anterior/métodos , Articulação do Joelho/cirurgia , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Imageamento por Ressonância Magnética , Meniscos Tibiais
4.
Angew Chem Int Ed Engl ; 62(4): e202216029, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36426408

RESUMO

Macrocycle engineering is a key topic in supramolecular chemistry. When synthesizing a ring, one can obtain either complex mixtures of macrocycles of different sizes or a single ring if a template is utilized. Here, we unite these approaches along with post-synthetic modifications to transform a single tether into multiple rings-up to five per tether. The macrocycles contain two bridged phenylpyridine ligands that are connected through a Pt atom, which defines the rings' shape, size, and host activity. All rings undergo redox reactions (between PtII and PtIV ) that allow for large conformational changes. Their reactivity, together with their host performance, is a convenient way to control the capture and release of guests, to mediate ring transformations, and to control pseudorotaxane-to-pseudorotaxane conversions. This novel approach could serve to assemble other libraries of small ring molecules, create cyclic polymers bridged by responsive-at-metal nodes, and produce processable mechanically interlocked molecules.

5.
Angew Chem Int Ed Engl ; 62(30): e202305525, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37208297

RESUMO

Metal-metal bonds have rarely been explored as active elements in supramolecular assemblies despite their unique potential to introduce responsive behavior. In this report, a dynamic molecular container composed of two cyclometalated Pt units is constructed using Pt-Pt bonds. This molecule-the flytrap-has a flexible jaw composed of two [18]crown-6 ethers that can adapt their shape to bind large inorganic cations with sub-micromolar affinity. Along with the spectroscopic and crystallographic characterization of the flytrap, we report its photochemical assembly, which allows the capture of ions and their transport from solution to the solid state. In addition, we have been able to recycle the flytrap to regenerate its starting material due to the reversible nature of the Pt-Pt bond. We believe that other molecular containers and materials for harvesting valuable substrates from solution could be assembled using the advances presented here.

6.
Chemistry ; 28(54): e202200862, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-35920581

RESUMO

Ring-opening metathesis polymerization (ROMP) of strained macrocycles is a key method to prepare diverse polymers. However, lack of ring strain in most macrocycles is an impediment to polymerization. In this paper, the polymerization/oligomerization of unstrained macrocycles was achieved using a supramolecular approach, leading selectively to cyclic products. Diphenyl thiourea and other guest molecules were used as additives to the ROMP reaction of unstrained macrocycles. An intermediate host-guest complex leads to the stabilization of the open form of the macrocycle after treatment with Grubbs catalysts, thereby favoring polymerization by inhibiting the ring-closing reaction back to the monomer. This proof-of-concept enables ring-expansion polymerization of unstrained macrocycles leading to cyclic polymers with molecular weights up to 6700 Da.

7.
Inorg Chem ; 61(7): 2999-3006, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-34797043

RESUMO

Multiresponsive materials can adapt to numerous changes in their local environment, which makes them highly valuable for various applications. Although nanostructured and polymeric multiresponsive materials are plentiful, small-molecule analogues are scarce. This work presents a compact cyclometalated platinum(II) complex that bears a crown ether cavity (18C6-PtII); the intimate ring/emitter connectivity is key to unlocking multiresponsiveness. Complex 18C6-PtII responds to (i) cationic guests, producing changes in luminescence in both solution and the solid state, (ii) solvent molecules, which perturb the packing of the complex in the solid state and cause reversible color changes, and (iii) solvent polarity, which leads to controlled aggregation. These responses may enable 18C6-PtII to function as a sensor for ions and solvents, or as a functional unit for the fabrication of hybrid supramolecular polymers and metallogels.

8.
BMC Public Health ; 20(1): 339, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183766

RESUMO

BACKGROUND: An Amerindian genetic background could play an important role in susceptibility to metabolic diseases, which have alarmingly increased in recent decades. Mexico has one of the highest prevalences of metabolic disease worldwide. The purpose of this study was to determine the prevalence of metabolic syndrome and its components in a population with high Amerindian ancestry. METHODS: We performed a descriptive, quantitative, and analytical cross-sectional study of 2596 adult indigenous volunteers from 60 different ethnic groups. Metabolic syndrome and its components were evaluated using the American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement criteria. RESULTS: The overall prevalence of metabolic syndrome in the indigenous Mexican population was 50.3%. Although females had a higher prevalence than males (55.6% vs. 38.2%), the males presented with combinations of metabolic syndrome components that confer a higher risk of cardiovascular disease. The most frequent metabolic syndrome component in both genders was low HDL-cholesterol levels (75.8%). Central obesity was the second most frequent component in females (61%), though it had a low prevalence in males (16.5%). The overall prevalence of elevated blood pressure was 42.7% and was higher in males than females (48.8 vs. 40%). We found no gender differences in the overall prevalence of elevated triglycerides (56.7%) or fasting glucose (27.9%). CONCLUSIONS: We documented that individuals with Amerindian ancestry have a high prevalence of metabolic syndrome. Health policies are needed to control the development of metabolic disorders in a population with high genetic risk.


Assuntos
Indígenas Norte-Americanos/estatística & dados numéricos , Síndrome Metabólica/epidemiologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/etnologia , México/epidemiologia , Pessoa de Meia-Idade , Obesidade Abdominal/epidemiologia , Obesidade Abdominal/etnologia , Prevalência , Fatores de Risco
9.
Angew Chem Int Ed Engl ; 59(26): 10348-10352, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32222012

RESUMO

We report the synthesis, characterization, and spectroscopic investigations of a new responsive-at-metal cyclometalated platinum(II) complex. With mild chemical oxidants and reductants, it was possible to obtain the same complex in three different oxidation states and each of these complexes was structurally characterized by single-crystal X-ray diffraction. We discovered that the platinum(II) complex displays strong solvatochromism in the solid state, which can be attributed to modulation of Pt⋅⋅⋅Pt interactions that results in switching between optical and photoluminescent states. Incorporating responsive-at-metal species as dynamic components in nanostructured materials might facilitate response amplification, sensing, actuation, or self-healing processes.

10.
Angew Chem Int Ed Engl ; 59(12): 4705-4710, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-31943580

RESUMO

Cellulose nanocrystals (CNCs) spontaneously assemble into gels when mixed with a polyionic organic or inorganic salt. Here, we have used this ion-induced gelation strategy to create functional CNC gels with a rigid tetracationic macrocycle, cyclobis(paraquat-p-phenylene) (CBPQT4+ ). Addition of [CBPQT]Cl4 to CNCs causes gelation and embeds an active host inside the material. The fabricated CNC gels can reversibly absorb guest molecules from solution then undergo molecular recognition processes that create colorful host-guest complexes. These materials have been implemented in gel chromatography (for guest exchange and separation), and as elements to encode 2- and 3-dimensional patterns. We anticipate that this concept might be extended to design a set of responsive and selective gel-like materials functioning as, for instance, water-pollutant scavengers, substrates for chiral separations, or molecular flasks.

11.
J Environ Manage ; 237: 576-584, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30826639

RESUMO

In this paper we present modifications to previously published models for determining the specific volume of non-aqueous phase liquids (LNAPLs) in the subsurface at and near the groundwater table following a spill or leak from the soil surface. The modifications account for porous media having multimodal pore-size distributions as is often the case with tropical soils. Data from the literature are used to show that the use of multimodal pore-size distributions can lead to significantly different subsurface LNAPL specific volume predictions and possible LNAPL recovery rates, compared to when only unimodal pore-size distributions are considered. Differences of up to 200% are possible when the dual-porosity nature of the pore system is ignored, which can yield erroneous estimates of the time needed to remediate LNAPLs from contaminated areas when conventional systems are employed.


Assuntos
Água Subterrânea , Poluentes do Solo , Porosidade , Solo
12.
Ecotoxicol Environ Saf ; 165: 367-375, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30216895

RESUMO

Sugarcane vinasse is a residue generated at a rate fifteen times greater than the ethanol production. Because of its high organic and micronutrient content, this residue is used as a fertilizer on sugarcane crops. However, when used in large quantities, vinasse can saturate the soil and contaminate nearby water resources by percolation and leaching. Given the proven toxic potential of in natura vinasse, the present study aimed to evaluate the toxic potential of leached sugarcane vinasse using Nile tilapia (Oreochromis niloticus) as a test organism. A bioassay was performed after vinasse percolation in laboratory soil columns. The bioassay included one control group containing fresh water and two treatment groups, the first exposed to a 2,5% dilution of leached of vinasse and the second to a 2,5% dilution of in natura vinasse. After exposure, histopathological analysis was performed in gills and livers, and the latter were labelled for HSP70 proteins. No significant changes were detected in the gills of the exposed fish. However, in the liver, both in natura and leached vinasse induced statistically significant histopathological changes. These changes include hydropic degeneration, cell boundary losses, pyknotic nuclei and cellular disorganization. HSP70 expression significant increase in liver of both treatment groups were observed, being higher for the in natura vinasse exposed group. Results suggested that both leached vinasse and in natura vinasse were toxic, its still able to provoke histological changes and induce the cytoprotective response in exposed fish liver, evidenced by a immunostaining of cellular stress proteins. Thus, in order to reduce its environmental impact, appropriated effluent disposal is essential.


Assuntos
Ciclídeos , Misturas Complexas/toxicidade , Etanol/toxicidade , Brânquias/patologia , Proteínas de Choque Térmico HSP70/metabolismo , Fígado/patologia , Animais , Etanol/metabolismo , Fertilizantes/toxicidade , Brânquias/metabolismo , Fígado/metabolismo , Saccharum , Poluentes Químicos da Água/toxicidade
13.
New Microbiol ; 41(3): 235-237, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29620788

RESUMO

Campylobacter spp. are one of the most frequent causes of bacterial diarrhea worldwide. Although severe diarrhea is not highly prevalent, the risk of a fatal outcome is increased when infection is caused by strains resistant to macrolides, fluoroquinolones, and/or tetracyclines. It is therefore necessary to test the susceptibility of these bacteria to other antibiotics such as colistin, which may serve as an alternative therapeutic option in these situations. The E-test was used to investigate the activity of erythromycin and colistin against 30 clinical isolates of Campylobacter spp. The MIC values obtained (range: 0.38-8 mg/liter) were sufficiently low, given the elevated concentrations that colistin sulfate can reach in the intestinal lumen, for this antibiotic to be considered useful to treat severe diarrhea caused by Campylobacter spp. resistant to first-line antibiotics.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/microbiologia , Campylobacter coli/efeitos dos fármacos , Campylobacter jejuni/efeitos dos fármacos , Colistina/farmacologia , Farmacorresistência Bacteriana , Eritromicina/farmacologia , Humanos , Testes de Sensibilidade Microbiana
14.
Molecules ; 23(10)2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30326560

RESUMO

Fique fibers, native to Colombia, are traditionally used for ropes and bags. In the extraction of long fibers for these purposes, the same amount of short fibers is generated; the short fibers are then discarded in the soil or in landfills. This agro-industrial waste is cellulose-rich and can be potentially developed into new biobased products. As an alternative use for these fibers, viscose regenerated fibers with potential applications in the textile industry were developed. Fique waste fibers were pulped (to produce fique cellulose pulp, FCP) using a 3³ design of experiment (DOE) to adjust the variables of the whitening treatment, and DOE analysis showed that time and hydrogen peroxide concentration do not have a significant effect on non-cellulosic remotion, unlike temperature. The behavior of this pulp in the production of viscose was compared against that of commercially available wood cellulose pulp (WCP). FCP showed a suitable cellulose content with a high degree of polymerization, which makes it a viable pulp for producing discontinuous viscose rayon filaments. Both pulps showed the same performance in the production of the viscose dope and the same chemical, thermal, and mechanical behavior after being regenerated.


Assuntos
Celulose/química , Eliminação de Resíduos/métodos , Colômbia , Fibra de Algodão , Resíduos Industriais , Reciclagem , Indústria Têxtil , Têxteis
15.
Knee Surg Sports Traumatol Arthrosc ; 25(6): 1849-1856, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27256278

RESUMO

PURPOSE: The purpose of this study was to describe the angle of clinical failure during cyclical mobilization exercises in the Achilles tendon of human cadaveric specimens that were repaired using the Dresden technique and FiberWire® No. 2. The secondary aim was to identify the secure limit of mobilization, the type of failure, and the type of apposition. METHODS: The lower limbs of eight males (mean age: 60.3 ± 6.3 years) were repaired with the Dresden technique following complete, percutaneous mid-substance Achilles tendon rupture. A basal tension of 10 N at 30° of plantarflexion was placed on each specimen. The angle of the ankle during clinical failure (tendon ends separation >5 mm) was then tested via cyclical exercises (i.e. 100 cycles between 30° and 15° of plantarflexion; 100 cycles between 15° of plantarflexion and 0°; 100 cycles between 0° and 15° of dorsiflexion; and 100 cycles between 15° of dorsiflexion and full dorsiflexion). Clinical failure was determined using the Laplacian edge detection filter, and the angle of clinical failure was obtained using a rotatory potentiometer aligned in relation to the intermalleolar axis of each foot specimen. The type of failure (knot, tendon, or suture) and apposition (termino-terminal or non-termino-terminal) were determined. Descriptive statistics were used to obtain the mean; standard deviation; 95 % confidence interval; 1st, 25th, 50th, 75th, and 100th percentiles; and the standard error of the mean for angle data. Proportions were used to describe the type of failure and apposition. RESULTS: The main results were a mean angle of clinical failure equal to 12.5° of plantarflexion, a limit of mobilization equal to 14.0° of plantarflexion, tendon failure type, and non-termino-terminal apposition in all specimens. CONCLUSIONS: While the mean angle of clinical failure in human cadaveric models was 12.5° of plantarflexion, after 14.0° of plantarflexion, the percutaneous Dresden technique was found insecure for cyclical mobilization exercises, with a 5 % range of error. These findings are clinically relevant as they provide mechanical limits for diminishing the risk of Achilles lengthening during immediate rehabilitation.


Assuntos
Tendão do Calcâneo/lesões , Tendão do Calcâneo/cirurgia , Tendão do Calcâneo/fisiopatologia , Tornozelo/fisiopatologia , Terapia por Exercício , Humanos , Masculino , Pessoa de Meia-Idade , Ruptura/fisiopatologia , Ruptura/cirurgia , Técnicas de Sutura , Falha de Tratamento
16.
Emerg Med J ; 33(9): 611-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27207345

RESUMO

OBJECTIVE: Emergency Triage Assessment and Treatment (ETAT) was developed by the WHO to teach paediatric assessment, triage and initial management to healthcare workers (HCWs) in resource-limited hospital-based settings. This study sought to evaluate the extension of ETAT training from a regional hospital to paediatric HCWs at local primary care health centres (PHCs) in Guatemala. METHODS: Prior to providing a 16 h ETAT training module, immediately after, and at 3, 6 and 12 months, we used written pre-tests and post-tests and five-point Likert surveys to evaluate, respectively, clinical knowledge and provider confidence in providing acute care paediatrics; hands-on clinical skills were tested at 3, 6 and 12 months. RESULTS: Fifty-two HCWs (14 general physicians, 38 nurses) from four regional PHCs participated; 65%, 60% and 46% completed 3-month, 6-month and 12-month follow-ups, respectively. Test scores show significant acquisition of clinical knowledge initially, which was retained over time when tested at 3, 6 and 12 months (46 vs 70, p<0.001). Hands-on clinical skills scores demonstrated retention at 3, 6 and 12 months. Although participants were more confident about acute care paediatrics immediately after training (66 vs 104, p<0.001), this decreased with time, though not to pre-intervention levels. CONCLUSIONS: ETAT trainings were successfully extended to PHCs in a resource-limited setting with significant knowledge acquisition and retention over time and improved HCW confidence with acute care paediatrics. This process could serve as a successful model for in-country and international scale-up of ETAT.


Assuntos
Medicina de Emergência/educação , Pediatria/educação , Atenção Primária à Saúde/organização & administração , Programas Médicos Regionais/organização & administração , Triagem , Competência Clínica , Países em Desenvolvimento , Avaliação Educacional , Feminino , Clínicos Gerais/educação , Guatemala , Humanos , Masculino , Recursos Humanos de Enfermagem Hospitalar/educação , Estudos Prospectivos , Encaminhamento e Consulta
17.
Pediatr Emerg Care ; 32(8): 525-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25426683

RESUMO

OBJECTIVES: This study aimed to develop and implement an Emergency Triage Assessment and Treatment (ETAT) training program at a Guatemalan public hospital. Collaborators included Baylor College of Medicine/Texas Children's Hospital, the Guatemalan Ministry of Health, and the Pan American Health Organization. METHODS: The ETAT is a World Health Organization program to teach pediatric assessment, triage, and initial management to health care workers in resource-limited settings. The Baylor College of Medicine/Texas Children's Hospital created ETAT training materials in Spanish (Clasificación, Evaluación y Tratamiento de Emergencias Pediátricas [CETEP]) and conducted a train-the-trainer course for Hospital Nacional Pedro Bethancourt (HNPB) health care leadership. The HNPB subsequently conducted local trainings using a modified curriculum. Midcourse modifications based on evaluations and focus groups included distribution of manuals before training and an adding a day to the course.Course quality was assessed using participant evaluations and comparing pretest and posttest scores. Effectiveness was defined as 90% concordance between triage levels assigned by participants and facilitators. RESULTS: A total of 249 health care workers were trained by 24 HNPB facilitators. Mean pretest and posttest scores were 55 and 70, respectively (P < 0.001). On a 4-point scale, participants rated overall course quality and effectiveness as 3.6. Mean pretest (49 vs 58, P = 0.002) and posttest scores (68 vs 72, P = 0.01) improved for groups trained after modifications, as did evaluations for course quality (3.4 vs 3.7, P < 0.001) and effectiveness (3.4 vs 3.8, P < 0.001). Triage levels were assigned with 95% concordance (confidence interval, 91.9-97.3) between participants and facilitators. CONCLUSIONS: Hospital Nacional Pedro Bethancourt experts conducted high-quality trainings with locally relevant CETEP (ETAT) material. Trainings were effective and well received. The pediatric emergency department at HNPB now uses a triage system based on CETEP (ETAT).


Assuntos
Serviço Hospitalar de Emergência/normas , Pessoal de Saúde/educação , Hospitais Pediátricos/normas , Triagem/normas , Feminino , Guatemala , Humanos , Masculino , Melhoria de Qualidade , Recursos Humanos
18.
Molecules ; 21(12)2016 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-27898047

RESUMO

Urease is a nickel-dependent amidohydrolase that catalyses the decomposition of urea into carbamate and ammonia, a reaction that constitutes an important source of nitrogen for bacteria, fungi and plants. It is recognized as a potential antimicrobial target with an impact on medicine, agriculture, and the environment. The list of possible urease inhibitors is continuously increasing, with a special interest in those that interact with and block the flexible active site flap. We show that disulfiram inhibits urease in Citrullus vulgaris (CVU), following a non-competitive mechanism, and may be one of this kind of inhibitors. Disulfiram is a well-known thiol reagent that has been approved by the FDA for treatment of chronic alcoholism. We also found that other thiol reactive compounds (l-captopril and Bithionol) and quercetin inhibits CVU. These inhibitors protect the enzyme against its full inactivation by the thiol-specific reagent Aldrithiol (2,2'-dipyridyl disulphide, DPS), suggesting that the three drugs bind to the same subsite. Enzyme kinetics, competing inhibition experiments, auto-fluorescence binding experiments, and docking suggest that the disulfiram reactive site is Cys592, which has been proposed as a "hinge" located in the flexible active site flap. This study presents the basis for the use of disulfiram as one potential inhibitor to control urease activity.


Assuntos
Dissulfiram/farmacologia , Inibidores Enzimáticos/farmacologia , Reagentes de Sulfidrila/farmacologia , Urease/antagonistas & inibidores , Aprovação de Drogas/legislação & jurisprudência , Cinética , Estados Unidos , United States Food and Drug Administration
19.
Chem Sci ; 15(2): 431-441, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38179527

RESUMO

Humankind's manipulation of platinum dates back more than two millennia to burial objects. Since then, its use has evolved from purely decorative purposes in jewelry to more functional applications such as in catalysts, pharmaceuticals, and bioimaging agents. Platinum offers a range of properties arguably unmatched by any other metal, including electroactivity, photoluminescence, chromic behaviour, catalysis, redox reactivity, photoreactivity, and stimuli-controlled intermetallic interactions. The vast body of knowledge generated by the exploration of these and other properties of platinum has recently merged with other areas of chemistry such as supramolecular and host-guest chemistry. This has shown us that platinum can incorporate its responsive character into supramolecular assemblies (e.g., macrocycles and polymers) to produce materials with tailorable functions and responses. In this Perspective Article, we cover some platinum-powered supramolecular structures reported by us and others, hoping to inspire new and exciting discoveries in the field.

20.
Chem Sci ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39282641

RESUMO

Cyclometalated platinum complexes play a crucial role in catalysis, bioimaging, and optoelectronics. Phenylpyridines are widespread cyclometalating ligands that generate stable and highly emissive Pt complexes. While it is common practice to modify these ligands to fine-tune their photophysical properties, the incorporation of polycyclic aromatic hydrocarbons into the ligand's structure has been largely overlooked. This report describes the cyclometalation of naphthalenyl- and anthracenylpyridine ligands, which has resulted in ten new luminescent PtII and PtIV complexes. These species are enabled by a dual-binding behavior discovered in our polyaromatic-containing ligands. The introduction of naphthalenyl and anthracenyl groups unlocks dual binding modes, with the Pt center bonding to either of two distant carbon atoms within the ligand. These complexes exhibit both symmetric structures with two 5-membered metallacycles and asymmetric structures with 5- and 6-membered metallacycles. This work presents a strategy for the regioselective synthesis of Pt complexes with bespoke structures and photophysical properties. Our findings offer new opportunities in platinum chemistry and beyond, with potential implications for materials and technologies.

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