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1.
Pacing Clin Electrophysiol ; 47(2): 203-210, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38240391

RESUMEN

BACKGROUND: Balloon Tipped Temporary Pacemakers (BTTP) are the most used temporary pacemakers; however, they are associated with a risk of dislodgement and thromboembolism. Recently, Temporary Permanent Pacemakers (TPPM) have been increasingly used. Evidence of outcomes with TPPM compared to BTTP remains scarce. METHODS: Retrospective, chart review study evaluating all patients who underwent temporary pacemaker placement between 2014 and 2022 (N = 126) in the cardiac catheterization laboratory (CCL) at a level 1 trauma center. Primary outcome of this study is to evaluate the safety profile of TPPM versus BTTP. Secondary objectives include patient ambulation and healthcare utilization in patients with temporary pacemakers. RESULTS: Both groups had similar baseline characteristics distribution including gender, race, and age at temporary pacemaker insertion (p > .05). Subclavian vein was the most common site of access for the TPPM cohort (89.0%) versus the femoral vein in the BTTP group (65.1%). Ambulation was only possible in the TPPM group (55.6%, p < .001). Lead dislodgement, venous thromboembolism, local hematoma, and access site infections were less frequently encountered in the TPPM group (OR = 0.23 [95% CI (0.10-0.67), p < .001]). Within the subgroup of patients with TPPM, 36.6% of the patients were monitored outside the ICU setting. There was no significant difference in the pacemaker-related adverse events among patients with TPPM based on their in-hospital setting. CONCLUSION: TPPM is associated with a more favorable safety profile compared to BTTP. They are also associated with earlier patient ambulation and reduced healthcare utilization.


Asunto(s)
Marcapaso Artificial , Humanos , Estudios Retrospectivos
2.
Echocardiography ; 41(1): e15728, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38113338

RESUMEN

INTRODUCTION: An arteriovenous fistula (AVF) in patients with end-stage kidney disease (ESKD) can influence flow states. We sought to evaluate if assessment of aortic stenosis (AS) by transthoracic echocardiographic (TTE) differs in the presence of AVF compared to other dialysis accesses in patients on dialysis. METHODS: We identified consecutive ESKD patients on dialysis and concomitant AS from a single center between January 2000 and March 2021. We analyzed TTE parameters of AS severity (velocities, gradients, aortic valve area [AVA]) and hemodynamics (cardiac output [CO], valvuloarterial impedance [Zva]) and compared AS parameters in patients with AVF versus other dialysis access. RESULTS: The cohort included 94 patients with co-prevalent ESKD and AS; mean age 66 years, 71% male; 43% Black, 24% severe AS. Dialysis access: 53% AVF, 47% others. In the overall cohort, no significant differences were noted between AVF versus non-AVF in AVA/CO/Zva, but with notable subgroup differences. In mild AS, CO was significantly higher in AVF versus non-AVF (6.3 vs. 5.2 L/min; p = .04). In severe AS, Zva was higher in the AVF versus non-AVF (4.6 vs. 3.6 mm Hg/mL/m2 ). With increasing AS severity in the AVF group, CO decreased, coupled with increase in Zva, likely counterbalancing the net hemodynamic impact of the AVF. CONCLUSION: Among ESKD patients with AS, TTE parameters of flow states and AS severity differed in those with AVF versus other dialysis accesses and varied with progression in severity of AS. Future longitudinal assessment of hemodynamic parameters in a larger cohort of co-prevalent ESRD and AS would be valuable.


Asunto(s)
Estenosis de la Válvula Aórtica , Derivación Arteriovenosa Quirúrgica , Fallo Renal Crónico , Humanos , Masculino , Anciano , Femenino , Diálisis Renal , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Ecocardiografía , Hemodinámica
3.
Catheter Cardiovasc Interv ; 102(2): 179-190, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37381622

RESUMEN

OBJECTIVES: We sought to study the association of renal impairment (RI) with mortality in ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock and/or cardiac arrest (CS/CA). METHODS: Patients with RI (estimated glomerular filtration rate <60 mL/min/1.73 m2 ) were identified from the Midwest STEMI consortium, a prospective registry of four large regional programs comprising consecutive patients over 17 years. Primary outcome was in-hospital and 1-year mortality stratified by RI status and presence of CS/CA among patients with STEMI referred for coronary angiography. RESULTS: In a cohort of 13,463 STEMI patients, 13% (n = 1754) had CS/CA, 30% (n = 4085) had RI. Overall, in-hospital mortality was 5% (12% RI vs. 2% no-RI, p < 0.001) and 1-year mortality 9% (21% RI vs. 4% no-RI, p < 0.001). Among uncomplicated STEMI, in-hospital mortality was 2% (4% RI vs. 1% no-RI, p < 0.001) and 1-year mortality 6% (13% RI vs. 3% no-RI, p < 0.001). In STEMI with CS/CA, in-hospital mortality was 29% (43% RI vs. 15% no-RI, p < 0.001) and 1-year mortality 33% (50% RI vs. 16% no-RI, p < 0.001). Using Cox proportional hazards, RI was an independent predictor of in-hospital mortality in STEMI with CS/CA (odds ratio [OR]: 3.86; confidence interval [CI]: 2.6, 5.8). CONCLUSIONS: The association of RI with in-hospital and 1-year mortality is disproportionately greater in those with CS/CA compared to uncomplicated STEMI presentations. Factors predisposing RI patients to higher risk STEMI presentations and pathways to promote earlier recognition in the chain of survival need further investigation.


Asunto(s)
Paro Cardíaco , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Choque Cardiogénico/diagnóstico , Choque Cardiogénico/etiología , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Factores de Riesgo , Resultado del Tratamiento , Paro Cardíaco/diagnóstico , Mortalidad Hospitalaria , Intervención Coronaria Percutánea/efectos adversos
4.
Catheter Cardiovasc Interv ; 102(7): 1162-1176, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37870080

RESUMEN

AIMS: This analysis evaluates whether proportional serial cardiac troponin (cTn) change predicts benefit from an early versus delayed invasive, or conservative treatment strategies across kidney function in non-ST-elevation acute coronary syndrome (NSTE-ACS). METHODS: Patients diagnosed with NSTE-ACS in the Veterans Health Administration between 1999 and 2022 were categorized into terciles (<20%, 20 to ≤80%, >80%) of proportional change in serial cTn. Primary outcome included mortality or rehospitalization for myocardial infarction at 6 and 12 months, in survivors of index admission. Adjusted hazard ratio (HR) with 95% confidence Intervals (95% confidence interval [CI]) were calculated for the primary outcome for an early invasive (≤24 h of the index admission), delayed invasive (>24 h of index admission to 90-days postdischarge), or a conservative management. RESULTS: Chronic kidney disease (CKD) was more prevalent (45.3%) in the lowest versus 42.2% and 43% in middle and highest terciles, respectively (p < 0.001). Primary outcome is more likely for conservative versus early invasive strategy at 6 (HR: 1.44, 95% CI: 1.37-1.50) and 12 months (HR: 1.44, 95% CI: 1.39-1.50). A >80% proportional change demonstrated HR (95% CI): 0.90 (0.83-0.97) and 0.93 (0.88-1.00; p = 0.041) for primary outcome at 6 and 12 months, respectively, when an early versus delayed invasive strategy was used, across CKD stages. CONCLUSIONS: Overall, the invasive strategy was safe and associated with improved outcomes across kidney function in NSTE-ACS. Additionally, >80% proportional change in serial troponin in NSTE-ACS is associated with benefit from an early versus a delayed invasive strategy regardless of kidney function. These findings deserve confirmation in randomized controlled trials.


Asunto(s)
Síndrome Coronario Agudo , Intervención Coronaria Percutánea , Insuficiencia Renal Crónica , Humanos , Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/terapia , Troponina , Cuidados Posteriores , Resultado del Tratamiento , Alta del Paciente , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/terapia , Riñón , Intervención Coronaria Percutánea/efectos adversos , Angiografía Coronaria
5.
Environ Sci Technol ; 57(48): 19545-19556, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37956986

RESUMEN

Methane emissions from oil and gas production provide an important contribution to global warming. We investigate 2020 emissions from the largest gas field in Algeria, Hassi R'Mel, and the oil-production-dominated area Hassi Messaoud. We use methane data from the high-resolution (20 m) Sentinel-2 instruments to identify and estimate emission time series for 11 superemitters (including 10 unlit flares). We integrate this information in a transport model inversion that uses methane data from the coarser (7 km × 5.5 km) but higher-precision TROPOMI instrument to estimate emissions from both the 11 superemitters (>1 t/h individually) and the remaining diffuse area source (not detected as point sources with Sentinel-2). Compared to a bottom-up inventory for 2019 that is aligned with UNFCCC-reported emissions, we find that 2020 emissions in Hassi R'Mel (0.16 [0.11-0.22] Tg/yr) are lower by 53 [24-73]%, and emissions in Hassi Messaoud (0.22 [0.13-0.28] Tg/yr) are higher by 79 [4-188]%. Our analysis indicates that a larger fraction of Algeria's methane emissions (∼75%) come from oil production than national reporting suggests (5%). Although in both regions the diffuse area source constitutes the majority of emissions, relatively few satellite-detected superemitters provide a significant contribution (24 [12-40]% in Hassi R'Mel; 49 [27-71]% in Hassi Messaoud), indicating that mitigation efforts should address both. Our synergistic use of Sentinel-2 and TROPOMI can produce a unique and detailed emission characterization of oil and gas production areas.


Asunto(s)
Contaminantes Atmosféricos , Gas Natural , Gas Natural/análisis , Metano/análisis , Argelia , Contaminantes Atmosféricos/análisis , Yacimiento de Petróleo y Gas
6.
Circulation ; 143(25): e1088-e1114, 2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-33980041

RESUMEN

Aortic stenosis with concomitant chronic kidney disease (CKD) represents a clinical challenge. Aortic stenosis is more prevalent and progresses more rapidly and unpredictably in CKD, and the presence of CKD is associated with worse short-term and long-term outcomes after aortic valve replacement. Because patients with advanced CKD and end-stage kidney disease have been excluded from randomized trials, clinicians need to make complex management decisions in this population that are based on retrospective and observational evidence. This statement summarizes the epidemiological and pathophysiological characteristics of aortic stenosis in the context of CKD, evaluates the nuances and prognostic information provided by noninvasive cardiovascular imaging with echocardiography and advanced imaging techniques, and outlines the special risks in this population. Furthermore, this statement provides a critical review of the existing literature pertaining to clinical outcomes of surgical versus transcatheter aortic valve replacement in this high-risk population to help guide clinical decision making in the choice of aortic valve replacement and specific prosthesis. Finally, this statement provides an approach to the perioperative management of these patients, with special attention to a multidisciplinary heart-kidney collaborative team-based approach.


Asunto(s)
American Heart Association , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/terapia , Manejo de la Enfermedad , Insuficiencia Renal Crónica/diagnóstico por imagen , Insuficiencia Renal Crónica/terapia , Estenosis de la Válvula Aórtica/epidemiología , Comorbilidad , Ecocardiografía/normas , Humanos , Insuficiencia Renal Crónica/epidemiología , Medición de Riesgo/métodos , Estados Unidos/epidemiología
7.
Angew Chem Int Ed Engl ; 61(39): e202207484, 2022 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-35984673

RESUMEN

Starting from a molecular pharmacophore, which is a marker of drug action in medicinal molecules, we propose that the heterosynthon, a supramolecular synthon between unlike functional groups, plays an analogous role in the design and discovery of high bioavailability drugs. The heterosynthon could provide a more efficient and economical route to novel drugs.


Asunto(s)
Disponibilidad Biológica , Cristalización
8.
Antimicrob Agents Chemother ; 65(8): e0032121, 2021 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-34097482

RESUMEN

Recalcitrant dermatophytic infections of the glabrous skin (tinea corporis/cruris/faciei) pose a huge challenge to health care systems. Combinations of oral and topical drugs may potentially improve cure rates, but the same has never been objectively assessed for this condition in laboratory or clinical studies. The present study was undertaken with the aim of identifying synergistic combinations of oral and topical antifungals by testing clinical isolates obtained from patients with recalcitrant tinea corporis/cruris. Forty-two patients with tinea corporis/cruris who had failed oral antifungals or had relapsed within 4 weeks of apparent clinical cure were recruited. Twenty-one isolates were identified by sequencing (all belonging to the Trichophyton mentagrophytes/T. interdigitale species complex) and subjected to antifungal susceptibility testing (AFST) and squalene epoxidase (SQLE) gene mutation analysis. Finally, five isolates, four with underlying SQLE gene mutations and one wild-type strain, were chosen for checkerboard studies using various combinations of antifungal agents. Most isolates (n = 16) showed high MICs of terbinafine (TRB) (0.5 to >16 µg/ml), with SQLE gene mutations being present in all isolates with MICs of ≥0.5 µg/ml. Synergistic interactions were noted with combinations of itraconazole with luliconazole, TRB, and ketoconazole and propylene glycol monocaprylate (PGMC) with luliconazole and with the triple combination of PGMC with luliconazole and ketoconazole. In vitro synergistic interactions provide a sound scientific basis for the possible clinical use of antifungal combinations. Hence, these synergistic combinations may be tested for clinical utility in the wake of rising resistance among dermatophytic infections of the glabrous skin.


Asunto(s)
Tiña , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Arthrodermataceae , Farmacorresistencia Fúngica/genética , Humanos , Mutación , Glicoles de Propileno , Escualeno-Monooxigenasa/genética , Tiña/tratamiento farmacológico
9.
J Nutr ; 151(9): 2721-2730, 2021 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-34087933

RESUMEN

BACKGROUND: Few studies have evaluated whether plant-centered diets prevent progression of early stage chronic kidney disease (CKD). OBJECTIVES: We examined the association between plant-centered diet quality and early CKD markers. METHODS: We prospectively examined 2869 black and white men and women in the Coronary Artery Risk Development in Young Adults Study free of diagnosed kidney failure in 2005-2006 [examination year 20 (Y20); mean age: 45.3 ± 3.6  y]. CKD marker changes from Y20 to 2015-2016 (Y30) were considered, including estimated glomerular filtration rate (eGFR; serum creatinine), urinary albumin-to-creatinine ratio (ACR), and both. Diet was assessed through interviewer-administered diet histories at Y0, Y7, and Y20, and plant-centered diet quality was quantified with the A Priori Diet Quality Score (APDQS). Linear regression models were used to examine the association of APDQS and subsequent 10-y changes in CKD markers. RESULTS: After adjustment for sociodemographic, behavioral, and diet factors, we found that higher APDQS was related to less adverse changes in CKD markers in the subsequent 10-y period. Compared with the lowest APDQS quintile, the highest quintile was associated with an attenuated increase in lnACR (-0.25 mg/g; 95% CI: -0.37, -0.13 mg/g; P-trend < 0.001), whereas the highest quintile was associated with an attenuated decrease in eGFR (4.45 mL·min-1·1.73 m-2; 95% CI: 2.46, 6.43 mL·min-1·1.73 m-2). There was a 0.50 lower increase in combined CKD markers [ln(ACR) z score - eGFR z score] when comparing the extreme quintiles. Associations remained similar after further adjustment for hypertension, diabetes, and obesity as potential mediating factors. The attenuated worsening CKD marker changes associated with higher APDQS strengthened across increasing initial CKD category; those with the best diet and microalbuminuria in Y10-Y20 returned to high normal albuminuria (all P-interaction < 0.001). CONCLUSIONS: Individuals who consumed plant-centered, high-quality diets were less likely to experience deterioration of kidney function through midlife, especially among participants with initial stage characterized as mild CKD.


Asunto(s)
Vasos Coronarios , Insuficiencia Renal Crónica , Adulto , Albuminuria , Dieta , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/etiología , Factores de Riesgo , Adulto Joven
10.
J Appl Microbiol ; 130(4): 1259-1272, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32767623

RESUMEN

AIM: To investigate the genetic and pathogenic variability of Xanthomonas oryzae pv. oryzae causing bacterial blight in rice on the remote Andaman Islands, India. METHODS AND RESULTS: A total of 27 yellow-pigmented bacterial isolates representing rice fields of Andaman Islands incited blight on the susceptible-rice cultivar, C14-8. Phenotypic, pathogenic traits and 16S rRNA gene sequences revealed their identity as X. oryzae pv. oryzae. Virulence profiling indicated the prevalence of seven pathotypes of X. oryzae pv. oryzae on the Islands. Pathotypes-VI and -VII were highly virulent, whereas the pathotype-I was less virulent. Multilocus sequence typing based on nucleotide sequence polymorphism in nine housekeeping genes dnaK; fyuA; gyrB (two loci): rpoD; fusA; gapA; gltA and lepA clustered 27 isolates into 17 sequence types (STs) segregated into two clonal-complexes (CC). While CC-I comprised of isolates from Andaman Island, the CC-II is a mixture of isolates representing mainland India and Andaman Island. The data revealed trans-boundary pathogen introduction and a consequent intra-regional diversification on these islands due to the deployment of different rice cultivars in different regions. CONCLUSIONS: Genotyping and pathotyping of sland isolates revealed seven pathotypes distributed in two clonal complexes with strong indications for trans-boundary movement and consequent diversification of the bacterial pathogen. Highly virulent pathotypes of X. oryzae pv. oryzae that could overcome combinations of R-genes, xa13+Xa21 as well as xa5+xa13 were found prevalent in the Andaman Islands SIGNIFICANCE AND IMPACT OF THE STUDY: Genetic and virulence analysis of X. oryzae pv. oryzae in the Andaman Islands revealed introduction and host-mediated regional diversification and local adaptation of X oryzae pv. oryzae. The study calls for the need of multi-gene pyramiding for durable disease resistance and establishing stringent quarantine measures for safeguarding island agricultural practices in the future.


Asunto(s)
Oryza/microbiología , Enfermedades de las Plantas/microbiología , Xanthomonas/genética , Xanthomonas/patogenicidad , Proteínas Bacterianas/genética , India , Islas , Tipificación de Secuencias Multilocus , Oryza/clasificación , Polimorfismo Genético , ARN Ribosómico 16S/genética , Virulencia/genética , Xanthomonas/clasificación
11.
Echocardiography ; 38(10): 1817-1820, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34510536

RESUMEN

BACKGROUND: A hemodynamically significant arteriovenous fistula (AVF) in end-stage kidney disease (ESKD) causes a high flow state, resulting in pathologic cardiovascular remodeling, and deserves timely clinical recognition. CASE: A 55-year-old woman with history of ESKD with deceased donor kidney transplant with failing graft function and baseline creatinine of 2.8 mg/dl presented to the clinic with nocturnal cough, orthopnea, dyspnea on exertion and pedal edema. Physical exam was notable for large, aneurysmal right brachial AVF. Transthoracic echocardiography (TTE) revealed left ventricular (LV) enlargement and hypertrophy and elevated cardiac output (CO) of 10 L/min, raising a clinical concern for high-output heart failure. DECISION MAKING: A non-invasive assessment of the hemodynamic significance of the AVF was performed using a TTE. During temporary occlusion of the AVF, it was determined that about 27% of the resting CO was attributed to the AVF, suggesting hemodynamic significance. Nicoladoni-Israel-Branham sign was negative as there was no change in patient's heart rate, but this was potentially attributed to beta-blockade and chronic loading conditions. She underwent AVF banding and 2-month later her presenting symptoms resolved, and a TTE showed a decrease in resting CO of 7.6 L/min with normalization of LV size. CONCLUSION: This case highlights several teaching points. Firstly, in patients with ESKD, a large AVF can contribute to a high CO state resulting in maladaptive cardiovascular remodeling. Secondly, TTE evaluation of the hemodynamic contribution of an AVF can be performed with the application of the Nicoladoni-Israel-Branham sign. Finally, some experts recommend pre-emptive banding or ligation of AVF after successful kidney transplantation as this has been shown to have symptomatic and cardiovascular benefits.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Insuficiencia Cardíaca , Fallo Renal Crónico , Femenino , Insuficiencia Cardíaca/complicaciones , Humanos , Israel , Fallo Renal Crónico/complicaciones , Persona de Mediana Edad , Diálisis Renal
12.
J Emerg Med ; 60(3): 273-284, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33308915

RESUMEN

BACKGROUND: The current ST-elevation myocardial infarction (STEMI) vs. non-STEMI (NSTEMI) paradigm prevents some NSTEMI patients with acute coronary occlusion from receiving emergent reperfusion, in spite of their known increased mortality compared with NSTEMI without occlusion. We have proposed a new paradigm known as occlusion MI vs. nonocclusion MI (OMI vs. NOMI). OBJECTIVE: We aimed to compare the two paradigms within a single population. We hypothesized that STEMI(-) OMI would have characteristics similar to STEMI(+) OMI but longer time to catheterization. METHODS: We performed a retrospective review of a prospectively collected acute coronary syndrome population. OMI was defined as an acute culprit and either TIMI 0-2 flow or TIMI 3 flow plus peak troponin T > 1.0 ng/mL. We collected electrocardiograms, demographic characteristics, laboratory results, angiographic data, and outcomes. RESULTS: Among 467 patients, there were 108 OMIs, with only 60% (67 of 108) meeting STEMI criteria. Median peak troponin T for the STEMI(+) OMI, STEMI(-) OMI, and no occlusion groups were 3.78 (interquartile range [IQR] 2.18-7.63), 1.87 (IQR 1.12-5.48), and 0.00 (IQR 0.00-0.08). Median time from arrival to catheterization was 41 min (IQR 23-86 min) for STEMI(+) OMI compared with 437 min (IQR 85-1590 min) for STEMI(-) OMI (p < 0.001). STEMI(+) OMI was more likely than STEMI(-) OMI to undergo catheterization within 90 min (76% vs. 28%; p < 0.001). CONCLUSIONS: STEMI(-) OMI patients had significant delays to catheterization but adverse outcomes more similar to STEMI(+) OMI than those with no occlusion. These data support the OMI/NOMI paradigm and the importance of further research into emergent reperfusion for STEMI(-) OMI.


Asunto(s)
Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST , Infarto del Miocardio con Elevación del ST , Electrocardiografía , Humanos , Estudios Retrospectivos
13.
Angew Chem Int Ed Engl ; 60(23): 12841-12846, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33779114

RESUMEN

Higher cocrystal synthesis depends acutely on a knowledge of supramolecular synthons. We report three synthetic approaches towards ternary halogen bonded cocrystals that illustrate specificity and generality. Electrophilicity/nucleophilicity differences are needed among alternative sites of halogen bond formation. The two halogen bonds A⋅⋅⋅B and B⋅⋅⋅C in a halogen bonded ternary cocrystal ABC need to be of different strength. Interaction mimicry of hydrogen bonds by halogen bonds is a viable approach towards ternaries as illustrated with the pyrene structure. Finally, the crystal engineer should well be able to anticipate halogen bonds that are stronger than hydrogen bonds.

14.
Acc Chem Res ; 52(8): 2210-2220, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31318527

RESUMEN

Crystal engineering is the art and science of making crystals by design. Crystallization is inherently a purifying phenomenon. Bringing together more than one organic compound into the same crystal always needs deliberate action. Cocrystals are important because they offer a route to the controlled modulation of crystal properties. The route to cocrystal synthesis was opened up with the heterosynthon concept, which considers the complementary recognition of chemical groups from different molecules. Using this concept, binary cocrystals of enormous variety have been generated, even as crystal engineering has evolved into a form of solid-state supramolecular synthesis. Introducing a third component (a component is somewhat arbitrarily defined as an organic substance that is a solid at room temperature, mostly with the idea of excluding solvates) in a stoichiometric manner requires substantially greater effort and a careful balance of intermolecular interactions-their strengths, directional properties, and distance falloff characteristics. The first systematic ternary cocrystal synthesis was reported around 15 years ago. Drawing in a fourth component in stoichiometric amounts is exceedingly difficult, and we reported such syntheses in 2016. To date, a limited number of ternary cocrystals have been realized (around 120 in all, with a half from our group) and an even smaller number of quaternary cocrystals (around 30, all from our group, barring one). It is impressive that our experiments largely yielded the intended higher cocrystal (three- or four-component) with very small traces of contaminating binaries and pure compounds. A fifth or sixth component may be brought into the solid in the manner of a solid solution in that these components are situated at one of the sites of the quaternary cocrystal. To date, five components have not been included stoichiometrically within the same crystal. This is still an open challenge. The merit in synthesizing (higher) cocrystals is that one can systematically engineer property modularity: Each component is associated with a distinct property. This is important in the pharmaceutical industry, where each component can, in principle, confer a different, desirable property-drug action, solubility, or permeability. However, difficult synthetic targets are also addressed in chemistry simply because they are there. The intellectual satisfaction in making something that is very difficult to make renders the enterprise worthwhile in itself, and new chemistry usually gets uncovered in the process. The development of synthetic organic chemistry can undoubtedly be credited to various reliable methods for chemical transformations, and many difficult total syntheses were achieved by employing these methods over two centuries of research. In contrast, supramolecular synthesis (of multicomponent cocrystals and other assemblies) is in no way at a similar level of sophistication because the subject is still relatively young. Our group and others have reported the synthesis of many higher cocrystals with reliable, reproducible, and robust design strategies. There is a general perception that the isolation of some of these cocrystals is a matter of luck! The crux of this Account is that far from being a serendipitous matter, higher cocrystals may only be made with a judicious combination of strategy and methodology-the essence of synthesis.

15.
Mol Pharm ; 17(12): 4435-4442, 2020 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-32941048

RESUMEN

With the aim of developing multidrug solids through a tuned crystal engineering approach, we have selected two antiurinary infective drugs, namely, nitrofurantoin (NF) and trimethoprim (TMP) and isolated eight binary drug-drug solid solvates along with a nonsolvated cocrystal. Crystal structure analyses were performed for eight of these solids and rationalized in terms of known supramolecular synthons formed by pyrimidine, imide, and amine functionalities. Notably, the TMP-NF anhydrous cocrystal and its ionic cocrystal hydrate exhibit enhanced equilibrium solubilities compared to pure NF or the simple NF hydrate. Furthermore, the ionic cocrystal hydrate exhibits greater antibacterial activity against the Gram-negative bacteria, E. coli, compared to the parent TMP and NF at the lowest concentration of 3.9 µg/mL. This study indicates initial pathways using the cocrystal methodology that would help to eventually arrive at an antiurinary cocrystal with optimal properties.


Asunto(s)
Antiinfecciosos Urinarios/química , Composición de Medicamentos/métodos , Nitrofurantoína/química , Trimetoprim/química , Antiinfecciosos Urinarios/farmacología , Antiinfecciosos Urinarios/uso terapéutico , Química Farmacéutica/métodos , Cristalización , Combinación de Medicamentos , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Nitrofurantoína/farmacología , Nitrofurantoína/uso terapéutico , Solubilidad , Trimetoprim/farmacología , Trimetoprim/uso terapéutico , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología
16.
Harm Reduct J ; 17(1): 75, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33059666

RESUMEN

BACKGROUND AND AIMS: We characterized the extent and quality of respiratory sensations and sensory-related smoking cues associated with e-cigarette use among those who failed to quit combustible tobacco cigarette (CTC) use with traditional FDA approved medications but succeeded in doing so with e-cigarettes. Further, we sought to understand former smokers' perceptions about the influence of sensory experience with e-cigarette use on CTC cessation outcomes. METHODS: A nonrandom purposive sample of 156 participants recruited in the USA through the Consumer Advocates for Smoke Free Alternatives Association Facebook page completed an online cross-sectional survey to assess sensory experiences and smoking cues associated with e-cigarette use. Descriptive statistics were calculated, and the ANOVA/Kruskal-Wallis test with post hoc testing and the two-sample t test/Wilcoxon rank-sum test, as appropriate based on distribution, were used to assess the association between sample characteristics and sensory experiences and cues using investigator constructed questions, the Modified Cigarette Evaluation Questionnaire (mCEQ) and the Smoking Cue Appeal Survey (SCAS). RESULTS: With e-cigarette use, participants reported feeling the vapor in their throats, windpipes, noses, lungs, and on their tongues; reductions in nicotine craving; and enjoyment of their e-cigarette, including tasting, smelling, and seeing the vapor and touching the device. Women had greater craving reduction than men (p = 0.023). Those who began smoking at 13 years of age or younger had more satisfaction and had greater sensory enjoyment than those who began smoking at 16-17 years of age (p = 0.015 and p = 0.026, respectively), as well as greater sensory enjoyment than those who began smoking at 14-15 years of age (p = 0.047). There was a significant overall association between the number of years a respondent smoked and e-cigarette sensory enjoyment (p = 0.038). Participants 18-34 years old rated e-cigarettes as being more pleasant compared to 45 + years olds, (p = 0.012). Eighty-four percent of participants reported the sensation of the vapor as important in quitting CTCs, and 91% believed the sensations accompanying e-cigarette use contributed to their smoking cessation success. CONCLUSIONS: For those who failed to quit previously using approved cessation medications to stop smoking cigarettes, sensory experiences associated with e-cigarette use may help smokers quit smoking.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Fumadores/psicología , Vapeo , Adolescente , Adulto , Estudios Transversales , Señales (Psicología) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Acc Chem Res ; 51(11): 2957-2967, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30351918

RESUMEN

Mechanical properties of organic molecular crystals have been noted and studied over the years but the complexity of the subject and its relationship with diverse fields such as mechanochemistry, phase transformations, polymorphism, and chemical, mechanical, and materials engineering have slowed understanding. Any such understanding also needs conceptual advances-sophisticated instrumentation, computational modeling, and chemical insight-lack of such synergy has surely hindered progress in this important field. This Account describes our efforts at focusing down into this interesting subject from the viewpoint of crystal engineering, which is the synthesis and design of functional molecular solids. Mechanical properties of soft molecular crystals imply molecular movement within the solid; the type of property depends on the likelihood of such movement in relation to the applied stress, including the ability of molecules to restore themselves to their original positions when the stress is removed. Therefore, one is interested in properties such as elasticity, plasticity, and brittleness, which are linked to structural anisotropy and the degree to which a structure veers toward isotropic character. However, these matters are still by no means settled and are system dependent. While elasticity and brittleness are probably displayed by all molecular solids, the window of plasticity is perhaps the one that is most amenable to crystal engineering strategies and methods. In all this, one needs to note that mechanical properties have a kinetic component: a crystal that is elastic under slow stress application may become plastic or brittle if the same stress is applied quickly. In this context, nanoindentation studies have shown themselves to be of invaluable importance in understanding structural anisotropy. Several problems in solid state chemistry, including classical ones, such as the melting point alternation in aliphatic straight chain dicarboxylic acids and hardness modulation in solid solutions, have been understood more clearly with this technique. The way may even be open to picoindentation studies and the observation of molecular level movements. As in all types of crystal engineering, an understanding of the intermolecular interactions can lead to property oriented crystal design, and we present examples where complex properties may be deliberately turned on or off in organic crystals: one essentially fine-tunes the degree of isotropy/anisotropy by modulating interactions such as hydrogen bonding, halogen bonding, π···π interactions, and C-H···π interactions. The field is now wide open as is attested by the activities of several research groups working in the area. It is set to take off into the domains of smart materials, soft crystals, and superelasticity and a full understanding of solid state reactivity.

18.
Angew Chem Int Ed Engl ; 58(11): 3232-3234, 2019 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-30637893

RESUMEN

"Scientists owe it to society to provide guidance, leadership, and above all, moral stature, so that they become role models… Both knowledge and wealth are acquired only through the pursuit of truth. This is smoothly achieved when then there is a seamless exchange of unspoken thought between science and society. …" Read more in the Guest Editorial by G. R. Desiraju.

19.
Angew Chem Int Ed Engl ; 58(35): 12027-12031, 2019 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-31267635

RESUMEN

Formation of a stoichiometric quaternary cocrystal consisting of resorcinol (RES), tetramethylpyrazine (TMP), phenazine (PHE) and pyrene (PYR) is described. A closed tetrameric resorcinol-heterocycle synthon, unusual in that it has two different linker bases rather than just one, is observed in this four-component solid. The tetrameric synthon is formed by two RES molecules and the two pyridine bases TMP and PHE. The stoichiometric quaternary cocrystal grows in an epitaxial fashion on the surfaces of a RES.PHE binary cocrystal which is initially obtained from the mother liquor. By indexing the common crystal faces of the binary and quaternary cocrystals, and noting that no ternary solid is obtained, a plausible mechanism has been proposed for the formation of this rare supramolecular architecture.

20.
Angew Chem Int Ed Engl ; 58(13): 4100-4107, 2019 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-30488598

RESUMEN

Crystal Engineering has traditionally dealt with molecular crystals. It is the understanding of intermolecular interactions in the context of crystal packing and in the utilization of such understanding in the design of new solids with desired physical and chemical properties. We outline here five areas which come under the umbrella of Crystal Engineering and where we feel that a proper planning of research efforts could lead to higher dividends for science together with greater returns for humankind. We touch on themes and domains where science funding and translation efforts could be directed in the current climate of a society that increasingly expects applications and utility products from science and technology. The five topics are: 1) pharmaceutical solids; 2) industrial solid state reactions; 3) mechanical properties with practical applications; 4) MOFs and COFs framework solids; 5) new materials for solar energy harvesting and advanced polymers.

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