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1.
Angew Chem Int Ed Engl ; 63(18): e202402526, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38415379

ABSTRACT

Electrically conductive metal-organic frameworks (MOFs) are promising candidates for electrochemical capacitors (EC) for fast energy storage due to their high specific surface areas and potential for redox activity. To maximize energy density, traditional inorganic pseudocapacitors have utilized faradaic processes in addition to double-layer capacitance. Although conductive MOFs are usually comprised of redox active ligands which allow faradaic reactions upon electrochemical polarization, systematic studies providing deeper understanding of the charge storage processes and structure-function relationships have been scarce. Here, we investigate the charge storage mechanisms of a series of triazatruxene-based 2D layered conductive MOFs with variable alkyl functional groups, Ni3(HIR3-TAT)2 (TAT=triazatruxene; R=H, Et, n-Bu, n-Pent). Functionalization of the triazatruxene core allows for systematic variation of structural parameters while maintaining in-plane conjugation between ligands and metals. Specifically, R groups modulate interlayer spacing, which in turn shifts the charge storage mechanism from double-layer capacitance towards pseudocapacitance, leading to an increase in molar specific capacitance from Ni3(HIH3-TAT)2 to Ni3(HIBu3-TAT)2. Partial exfoliation of Ni3(HIBu3-TAT)2 renders redox active ligand moieties more accessible, and thus increases the dominance of faradaic processes. Our strategy of controlling charge storage mechanism through tuning the accessibility of redox-active sites may motivate further design and engineering of electrode materials for EC.

2.
J Am Chem Soc ; 2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37921430

ABSTRACT

Two-dimensional electrically conducting metal-organic frameworks (2D-e-MOFs) have emerged as a class of highly promising functional materials for a wide range of applications. However, despite the significant recent advances in 2D-e-MOFs, developing systems that can be postsynthetically chemically functionalized, while also allowing fine-tuning of the transport properties, remains challenging. Herein, we report two isostructural 2D-e-MOFs: Ni3(HITAT)2 and Ni3(HITBim)2 based on two new 3-fold symmetric ligands: 2,3,7,8,12,13-hexaaminotriazatruxene (HATAT) and 2,3,8,9,14,15-hexaaminotribenzimidazole (HATBim), respectively, with reactive sites for postfunctionalization. Ni3(HITAT)2 and Ni3(HITBim)2 exhibit temperature-activated charge transport, with bulk conductivity values of 44 and 0.5 mS cm-1, respectively. Density functional theory analysis attributes the difference to disparities in the electron density distribution within the parent ligands: nitrogen-rich HATBim exhibits localized electron density and a notably lower lowest unoccupied molecular orbital (LUMO) energy relative to HATAT. Precise amounts of methanesulfonyl groups are covalently bonded to the N-H indole moiety within the Ni3(HITAT)2 framework, modulating the electrical conductivity by a factor of ∼20. These results provide a blueprint for the design of porous functional materials with tunable chemical functionality and electrical response.

3.
Pediatr Emerg Care ; 39(2): 74-79, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36719387

ABSTRACT

OBJECTIVES: The diagnosis and treatment of mild traumatic brain injuries (mTBIs) by emergency medicine providers is greatly varied. Because of the frequency and long-term consequences associated with pediatric head injuries, it is crucial that adequate counseling is provided in acute care settings. The purpose of our study is to evaluate existing practices at Loyola University Medical Center emergency department to address inconsistencies in diagnostic or discharge practices and determine future quality improvement measures. METHODS: A retrospective cohort study was conducted at an academic hospital emergency department of patient records from 2017 to 2020. Demographic, diagnostic, and discharge data were summarized, and Pearson χ2 tests and Fisher exact tests were performed to determine associations among patient characteristics and provider practices. RESULTS: A total of 1160 patients met inclusion criteria for analysis. In terms of diagnostic procedure, 31.6% of providers did not uniformly use existing screening criteria, such as PECARN, to determine if CT scans were needed for mTBI evaluation. Most discharge instructions were based on a generalized template on epic (91.9%). Only a minority of providers prepared patient-specific instructions through written, verbal, or other supplemental materials. The most common formats included epic only (46.1%), epic and personalized written instructions (20.2%), and epic and verbal instructions (12.4%). Follow-up care instructions were provided to 93% of patients who received discharged instructions, mainly for primary care (96.7%), sports medicine (1.58%), neurology (0.65%), or other providers (1.11%). CONCLUSIONS: There is a lack of consistency in the evaluation and education of mTBI in pediatric patients. There is a need for personalized discharge instructions to ensure adequate patient and parent understanding and compliance. Further studies looking at long-term outcomes in these patients would also be beneficial.


Subject(s)
Brain Concussion , Craniocerebral Trauma , Humans , Child , Retrospective Studies , Brain Concussion/diagnosis , Brain Concussion/therapy , Craniocerebral Trauma/complications , Patient Discharge , Emergency Service, Hospital
4.
Adv Mater ; 35(6): e2207380, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36394175

ABSTRACT

Syngas, a mixture of CO and H2 , is a high-priority intermediate for producing several commodity chemicals, e.g., ammonia, methanol, and synthetic hydrocarbon fuels. Accordingly, parallel sunlight-driven catalytic conversion of CO2 and protons to syngas is a key step toward a sustainable energy cycle. State-of-the-art catalytic systems and materials often fall short as application-oriented concurrent CO and H2 evolution requires challenging reaction conditions which can hamper stability, selectivity, and efficiency. Here a light-harvesting metal-organic framework hosting two molecular catalysts is engineered to yield colloidal, water-stable, versatile nanoreactors for photocatalytic syngas generation with highly controllable product ratios. In-depth fluorescence, X-ray, and microscopic studies paired with kinetic analysis show that the host delivers energy efficiently to active sites, conceptually yielding nanozymes. This unlocked sustained CO2 reduction and H2 evolution with benchmark turnover numbers and record incident photon conversions up to 36%, showcasing a highly active and durable all-in-one material toward application in solar energy-driven syngas generation.

5.
Heart Lung ; 50(4): 477-480, 2021.
Article in English | MEDLINE | ID: mdl-33831699

ABSTRACT

BACKGROUND: Previous studies have explored the relationship between socioeconomic status and sepsis outcomes OBJECTIVES: The purpose of this investigation is to determine if race, ethnicity, economic stability, neighborhood environment, and access to health care are predictive of mortality in patients with septic shock. METHODS: Retrospective study of septic shock patients admitted to two medical centers. RESULTS: Caucasian patients had higher proportion of outpatient physician visits in the year prior to admission and were less likely to be Medicare or Medicaid beneficiaries. Thirty-day mortality was lower for the Caucasian cohort (39.3% vs. 48.7%, p < 0.01). Multivariate logistic regression found several predictors of 30-day mortality including Minority race/ethnicity (OR 1.44, 95% CI 1.12-1.86), unemployment (OR 1.40, 95% CI 1.09-1.81), and neighborhood poverty rate ≥10% (OR 1.43, 95% CI 1.01-2.01). CONCLUSIONS: Minority patients, unemployed patients, and those living in neighborhoods with poverty rates greater than 10% suffered from higher 30-day mortality when admitted for septic shock.


Subject(s)
Sepsis , Shock, Septic , Aged , Humans , Medicare , Retrospective Studies , Socioeconomic Factors , United States/epidemiology
6.
Cell Physiol Biochem ; 51(4): 1518-1532, 2018.
Article in English | MEDLINE | ID: mdl-30497079

ABSTRACT

BACKGROUND/AIMS: Blocking estrogen signaling with endocrine therapies (Tamoxifen or Fulverstrant) is an effective treatment for Estrogen Receptor-α positive (ER+) breast cancer tumours. Unfortunately, development of endocrine therapy resistance (ETR) is a frequent event resulting in disease relapse and decreased overall patient survival. The long noncoding RNA, H19, was previously shown to play a significant role in estrogen-induced proliferation of both normal and malignant ER+ breast epithelial cells. We hypothesized that H19 expression is also important for the proliferation and survival of ETR cells. METHODS: Here we utilized established ETR cell models; the Tamoxifen (Tam)-resistant LCC2 and the Fulvestrant and Tam cross-resistant LCC9 cells. Gain and loss of H19 function were achieved through lentiviral transduction as well as pharmacological inhibitors of the Notch and c-Met receptor signaling pathways. The effects of altered H19 expression on cell viability and ETR were assessed using three-dimensional (3D) organoid cultures and 2D co-cultures with low passage tumour-associated fbroblasts (TAFs). RESULTS: Here we report that treating ETR cells with Tam or Fulvestrant increases H19 expression and that it's decreased expression overcomes resistance to Tam and Fulvestrant in these cells. Interestingly, H19 expression is regulated by Notch and HGF signaling in the ETR cells and pharmacological inhibitors of Notch and c-MET signaling together significantly reverse resistance to Tam and Fulvestrant in an H19-dependent manner in these cells. Lastly, we demonstrate that H19 regulates ERα expression at the transcript and protein levels in the ETR cells and that H19 protects ERα against Fulvestrant-mediated downregulation of ERα protein. We also observed that blocking Notch and the c-MET receptor signaling also overcomes Fulvestrant and Tam resistance in 3D organoid cultures by decreasing ERα and H19 expression in the ETR cells. CONCLUSION: In endocrine therapy resistant breast cancer cells Fulvestrant is ineffective in decreasing ERα levels. Our data suggest that in the ETR cells, H19 expression acts as an ER modulator and that its levels and subsequently ERα levels can be substantially decreased by blocking Notch and c-MET receptor signaling. Consequently, treating ETR cells with these pharmacological inhibitors helps overcome resistance to Fulvestrant and Tamoxifen.


Subject(s)
Antineoplastic Agents, Hormonal/pharmacology , Breast Neoplasms/drug therapy , Drug Resistance, Neoplasm , Estrogen Receptor alpha/genetics , Fulvestrant/pharmacology , RNA, Long Noncoding/genetics , Tamoxifen/pharmacology , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans
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