50 research outputs found

    Pseudopolymorphs of 3,5-dinitrosalicylic acid

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    Seven pseudopolymorphs of 3,5-dinitrosalicylic acid are studied. Four of these (A-D) are obtained from dioxane and their formation is rationalised on the basis of simultaneous O-H … O and C-H … O bond formation between the donor-rich solute molecule and the multiple-acceptor solvent. A fifth (E) is a previously reported centrosymmetric hydrate. The sixth and seventh (F and G) are a non-centrosymmetric hydrate and a tert-butyl alcoholate whose structures are related to that of form E, in that hydrogen bonds are both donated and accepted between solute and solvent. The formation of this rich diversity of pseudopolymorphs with hydrogen bonding solvents follows from the nature of the title acid while the similarities between the structures of the pseudopolymorphs may be accounted for in terms of a permutation of a small number of solute-solvent supramolecular synthons. All this indicates that this interesting phenomenon may be both anticipated and also studied systematically. The scope of the term pseudopolymorph has been extended a little, in the expectation that such a definition would be of more general utility

    Arrhythmia-related Hospitalization and Comorbid Cannabis Use Disorder: Trend Analysis in US Hospitals (2010-2014)

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    Objective To study the trends of arrhythmia hospitalizations with cannabis use disorders (CUDs) in terms of demographic characteristics and inpatient outcomes. Methods We used the nationwide inpatient sample (NIS) data during the post-legalization period (2010-2014) and included 570,556 arrhythmia inpatients (age, 15-54 years), and 14,426 inpatients had comorbid CUD (2.53%). We used the linear-by-linear association test and independent-sample T-test for assessing the change in hospital outcomes in inpatients with CUD. Results Arrhythmia hospitalizations with CUD increased by 31% (2010-2014). This increasing trend was seen in adults (45-54 years, P < 0.001) and was predominant in males (77.6%). Hypertension (40.6%), hyperlipidemia (17.6%), and obesity (15%) were prevalent medical comorbidities with variable trends over the five years. Among substance use disorders, tobacco (50.9%), and alcohol (31.4%) were major comorbidities with a variable trend (P = 0.003 for each). There was a 71.4% increase in the inpatient mortality rate between 2010 (0.7%) and 2014 (1.2%). The mean length of stay was three days, and the total hospitalization charges have been increasing (P < 0.001), averaging $35,812 per hospital admission. Conclusion Chronic cannabis use or abuse worsens hospitalization outcomes in arrhythmic patients, and more clinical studies are needed to study the causal association between these conditions due to the rising mortality risk

    Problematic Cannabis Use and Risk of Complications in Patients with Chronic Hepatitis C

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    Objectives To evaluate the risk of complication in hospitalized chronic hepatitis C (CHC), patients with cannabis use disorder (CUD). Methods We conducted a retrospective study using the nationwide inpatient sample (NIS), and included 31,623 patients (age 15-54) with a primary international classification of diseases, ninth revision (ICD-9) diagnosis for CHC and grouped by co-diagnosis of CUD (1101, 3.5%). Logistic regression model adjusted for confounders was used to evaluate the odds ratio (OR) of CUD and complications during CHC hospitalization. Results Comorbid CUD was prevalent in males (73.2%), Caucasians (59.9%), and from low-income families (65.7%). The most prevalent complications in patients with CUD were ascites (44.9%), alcoholic cirrhosis (42.8%) and non-alcoholic cirrhosis (41.1%). The odds of association for hepatic encephalopathy was 2.2 times higher (95% CI 1.477-3.350) in 2.8% CHC inpatients with CUD compared to 1.2% non-CUD inpatients. Hepatic encephalopathy had higher odds of association with a male by 1.4 times (95% CI 1.094-1.760), and African American by 1.7 times (95% CI 1.293-2.259). Conclusion CUD is significantly associated with 122% increased likelihood for hepatic encephalopathy that may worsen overall hospitalization outcomes in CHC patients. Hence, we need to consider the complex relationship between CUD and CHC and manage them optimally to improve the health-related quality of life

    World Workshop on Oral Medicine VIII: Development of a core outcome set for oral lichen planus: a systematic review of outcome domains

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    Objective: There is a lack of consensus regarding clinician- and patient-reported oral lichen planus (OLP) outcomes. The World Workshop on Oral Medicine Outcomes Initiative for the Direction of Research (WONDER) Project aims to develop a core outcome set (COS) for OLP, which would inform the design of clinical trials and, importantly, facilitate meta-analysis, leading to the establishment of more robust evidence for the management of this condition and hence improved patient care. Study Design: Ovid MEDLINE, Embase, CINAHL, CENTRAL, and Clinicaltrials.gov were searched for interventional studies (randomized controlled trials, controlled clinical trials, and case series including ≥5 participants) on OLP and oral lichenoid reactions published between January 2001 and March 2022 without language restriction. All reported primary and secondary outcomes were extracted. Results: The searches yielded 9,135 records, and 291 studies were included after applying the inclusion criteria. A total of 422 outcomes were identified. These were then grouped based on semantic similarity, condensing the list to 69 outcomes. The most frequently measured outcomes were pain (51.9%), clinical grading of the lesions (29.6%), lesion size/extension/area (27.5%), and adverse events (17.5%). Conclusion: As a first step in developing a COS for OLP, we summarized the outcomes that have been used in interventional studies over the past 2 decades, which are numerous and heterogeneous.S

    World Workshop on Oral Medicine VIII: Development of a core outcome set for oral lichen planus: the patient perspective

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    Objective: This study aimed to explore the lived experience of patients with oral lichen planus (OLP) and investigate what treatment-related outcomes are the most important to them and should be included in a core outcome set (COS) for OLP. Study Design: A qualitative study involving focus group work with 10 participants was conducted. Interviews with each focus group were held twice: session 1 explored the lived experience of patients with OLP, and session 2 allowed patients to review a summary of the outcome domains used in the OLP literature to date. The discussions were recorded, transcribed verbatim, and analyzed using framework analysis. Results: In session 1, 4 themes and 8 sub-themes emerged from the data analysis. An additional outcome, ‘knowledge of family and friends,’ was suggested in session 2. Conclusions: We have gained valuable insight into the lived experience of patients with OLP via this qualitative study. To our knowledge, this study is the first to explore the patient perspective on what should be measured in clinical trials on OLP, highlighting an important additional suggested outcome. This additional outcome will be voted upon in a consensus process to determine a minimum COS for OLPS

    A robust binary supramolecular organic framework (SOF) with high CO2 adsorption and selectivity

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    A robust binary hydrogen-bonded supramolecular organic framework (SOF-7) has been synthesized by solvothermal reaction of 1,4-bis-(4-(3,5-dicyano-2,6 dipyridyl)dihydropyridyl)benzene (1) and 5,5’-bis-(azanediyl)-oxalyl-diisophthalic acid (2). Single crystal X-ray diffraction analysis shows that SOF-7 comprises 2 and 1,4-bis-(4-(3,5-dicyano-2,6-dipyridyl)pyridyl)benzene (3), the latter formed in situ from the oxidative dehydrogenation of 1. SOF-7 shows a three-dimensional four-fold interpenetrat-ed structure with complementary O−H···N hydrogen bonds to form channels that are decorated with cyano- and amide-groups. SOF-7 exhibits excellent thermal stability and sol-vent and moisture durability, as well as permanent porosity. The activated desolvated material SOF-7a shows high CO2 sorption capacity and selectivity compared with other po-rous organic materials assembled solely through hydrogen bonding

    Crystal structures and packing of 4-cyanocubanecarboxylic acid, its methyl ester, and the solid solution of 1,4-dicyanocubane and 1,4-dibromocubane

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    The crystal structure of 4-cyanocubanecarboxylic acid contains the same syn-anti carboxyl group catemer that is found in other cubane monocarboxylic acids. The cyano groups are arranged according to the type-II geometry, in that they are 21 screw-axis related. Curiously, there is a 5% orientational disorder of the cyano and anti carboxyl groups. The ester of the title acid packs isostructurally with the corresponding chloro and fluoro analogs because of the importance of the C-H…O hydrogen bond patterns. 1,4-Dicyanocubane forms solid solutions with 1,4-dibromocubane, but, interestingly, the crystal structure of the solid solution is distinct from that of either component. The formation of these solid solutions seems to be governed by shape and size factors

    Introduction to Single-Molecule Toroics

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    This book deals with molecular systems which host toroidal magnetic states, referred in the literature as single-molecule toroics (SMTs). The study of such molecules finds its origin in the broader context of molecular magnetism (MM) whose birth and rich history are detailed in Magneto-Structural Correlation in Exchange Coupled Systems, a book written by Willet, Gatteschi and Kahn in 1985. For further developments in MM, please refer to Kahn’s Molecular Magnetism first published in 1993; for recent developments, to the book Molecular Nanomagnets by Villain, Sessoli and Gatteschi published in 2006; and Introduction to Molecular Magnetism: From Transition Metals to Lanthanides by Benelli and Gatteschi from 2015. In recent decades, molecular-based magnetic materials have attracted a great deal of attention due to their potential applications in magnetic storage devices, molecular spintronics and quantum information technologies based on molecular qubits [1–3]. These magnetic materials are composed of molecules which, like traditional bulk magnets, are able to retain their magnetisation even after the removal of a magnetic field. Early dilution studies of this effect, however, readily demonstrated that molecular magnetism is resultant from the intrinsic magnetic anisotropy of the individual molecules and that, in fact, intermolecular interactions between constituent molecules are not necessary to observe the phenomenon. Considerable growth in molecular magnetism has led to the discovery of single-molecule magnets (SMMs), single-chain magnets (SCMs) and spin crossover (SCO) molecules [1–3]. So too has the SMT subdiscipline grown out of MM, in this case from the study of polynuclear molecular rings comprised of strongly, magnetically anisotropic molecules whose magnetic axes adopt a characteristic, non-collinear vortex configuration [4–7]

    Cubanecarboxylic acids. crystal engineering considerations and the role of C-H···O hydrogen bonds in determining O-H···O networks

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    A family of 4-substituted-1-cubanecarboxylic acids have been synthesized and their X-ray crystal structures analyzed. The rare syn-anti O-H...O catemer 6 is a recurring pattern in this series of compounds. Catemer 6 is observed in the crystal structures of 4-chloro-1-cubanecarboxylic acid (10), 4-bromo-1-cubanecarboxylic acid (11), 4-iodo-1-cubanecarboxylic acid (12), and 4-(methoxycarbonyl)-1-cubanecarboxylic acid (13). The ready occurrence of catemer 6 in this family is ascribed to its stabilization by auxiliary C-H···O hydrogen bonds formed by the relatively acidic cubyl C-H groups. The frequency of occurrence of 6 also facilitates its definition as a useful supramolecular synthon. As is true in many catemers, the formation of 6 is sensitive to steric factors. Therefore, the robustness of this synthon may be assessed by analyzing the crystal structures of molecules wherein the 4-substituent is too small (R = H, 14), too large (R = Ph, 15), or has a specific hydrogen bonding preference of its own (R = CONH2, 16). In these structures, either dimer 3 (in 14 and 15) or heterodimer 22 (in 16) is observed. Powder diffraction shows that the previously noted structure of 1,4-cubanedicarboxylic acid (7) that contains catemer 6 is characteristic of the bulk material. In summary, the syn-anti catemer is the dominant supramolecular synthon in this family of cubanecarboxylic acids
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