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1.
J Am Chem Soc ; 146(27): 18714-18721, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38924484

ABSTRACT

Mixed-valence dilanthanide complexes of the type (CpiPr5)2Ln2I3 (CpiPr5 = pentaisopropylcyclopentadienyl; Ln = Gd, Tb, Dy) featuring a direct Ln-Ln σ-bonding interaction have been shown to exhibit well-isolated high-spin ground states and, in the case of the Tb and Dy variants, a strong axial magnetic anisotropy that gives rise to a large magnetic coercivity. Here, we report the synthesis and characterization of two new mixed-valence dilanthanide compounds in this series, (CpiPr5)2Ln2I3 (1-Ln; Ln = Ho, Er). Both compounds feature a Ln-Ln bonding interaction, the first such interaction in any molecular compounds of Ho or Er. Like the Tb and Dy congeners, both complexes exhibit high-spin ground states arising from strong spin-spin coupling between the lanthanide 4f electrons and a single σ-type lanthanide-lanthanide bonding electron. Beyond these similarities, however, the magnetic properties of the two compounds diverge. In particular, 1-Er does not exhibit observable magnetic blocking or slow magnetic relaxation, while 1-Ho exhibits magnetic blocking below 28 K, which is the highest temperature among Ho-based single-molecule magnets, and a spin reversal barrier of 556(4) cm-1. Additionally, variable-field magnetization data collected for 1-Ho reveal a coercive field of greater than 32 T below 8 K, more than 6-fold higher than observed for the bulk magnets SmCo5 and Nd2Fe14B, and the highest coercive field reported to date for any single-molecule magnet or molecule-based magnetic material. Multiconfigurational calculations, supported by far-infrared magnetospectroscopy data, reveal that the stark differences in magnetic properties of 1-Ho and 1-Er arise from differences in the local magnetic anisotropy of the lanthanide centers.

2.
Phys Chem Chem Phys ; 26(25): 17539-17548, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38885049

ABSTRACT

Dy(III) bis-cyclopentadienyl (Cp) sandwich compounds exhibit extremely strong single-ion magnetic anisotropy which imbues them with magnetic memory effects such as magnetic hysteresis, and has put them at the forefront of high-performance single-molecule magnets (SMMs). Owing to the great success of design principles focused on maximising the anisotropy barrier, ever higher Ueff values have been reported leading to significant slow down of single-phonon Orbach spin relaxation. However, anisotropy-based SMM design has largely ignored two-phonon Raman spin relaxation, which is still limiting the temperatures at which a memory effect can be observed. In this work, we study the suppression of Raman relaxation through covalent bridging of the Cp ligands by alkyl chains, testing the hypothesis that increasing the rigidity of the ligand framework results in a blue shift of low frequency vibrations in the first coordination sphere of the Dy(III) ion. This reshaping of the vibrational low-energy density of states (DOS) results in lower occupation of pseudo-acoustic phonons available to drive Raman relaxation at low temperatures. We simulate Orbach and Raman spin relaxation in a series of zero-, mono-, di- and tri-bridged [Dy(Cpttt)2]+ analogues fully ab initio, using a quantum mechanics (QM)/molecular mechanics (MM) condensed phase embedding protocol in a periodic solvent matrix as a generic and experimentally testable environment model that can include (pseudo-)acoustic phononic degrees of freedom. We show that this approach can simulate magnetic relaxation dynamics in the condensed phase for the existing non-bridged [Dy(Cpttt)2]+ compound with quantitative experimental accuracy. Subsequently, we find a significant slowing down of Raman relaxation can be achieved for the singly-bridged SMM, while the introduction of further bridges leads to faster relaxation. A key result being that we find the two-phonon Raman rates correlate with the purity of the first-excited Kramers doublet in terms of its mJ = ±13/2 content. Even though the bridging design principle is successful at progressively reshaping the low-energy DOS, the introduction of linker atoms in the equatorial plane successively degrades magnetic anisotropy, suggesting the importance of refined design of the linker chemistry. The accuracy of our results emphasises the value of a generic periodic solvent embedding model, such that it permits the modelling of molecular spin dynamics in the condensed phase without knowledge of a crystal structure. This allows the study of hypothetical molecules or aggregates under real-world conditions, which we expect to have utility beyond the field of molecular magnetism.

3.
EClinicalMedicine ; 72: 102624, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38737002

ABSTRACT

Background: Previous studies have indicated that glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) may enhance bone formation and have neutral or beneficial effects on fracture risk. We evaluated the effect of the GLP-1RA semaglutide on the bone formation marker Procollagen type I N-terminal propeptide (PINP) in adults with increased fracture risk. Methods: This randomised, placebo-controlled, double-blinded, phase 2 clinical trial was conducted at two public hospitals in Denmark. We enrolled 64 men and women with increased fracture risk based on a T-score < -1.0 at the total hip or lumbar spine and/or low-energy fracture within three years of recruitment. Participants were randomised (1:1) to receive once-weekly subcutaneous semaglutide 1.0 mg or placebo. The primary outcome was changes in plasma (P)-PINP from baseline to week 52. Primary and safety outcomes were assessed and evaluated for all participants. This trial is complete and registered with ClinicalTrials.gov, NCT04702516. Findings: Between March 24 and December 8, 2021, 55 (86%) postmenopausal women and nine men with a mean age of 63 years (SD 5.5) and BMI of 27.5 kg/m2 (SD 4.5) were enrolled. There was no effect on changes in P-PINP from baseline to week 52 between the two groups (estimated treatment difference (ETD) semaglutide versus placebo 3.8 µg/L [95% CI -5.6 to 13.3]; p = 0.418), and no difference in P-PINP levels between groups at week 52 (semaglutide 64.3 µg/L versus placebo 62.3 µg/L [95% CI -10.8 to 15.0]; p = 0.749). The secondary outcomes showed higher plasma levels of bone resorption marker Collagen type I cross-linked C-terminal telopeptide (P-CTX) in the semaglutide group than in the placebo group (ETD 166.4 ng/L [95% CI 25.5-307.3]; p = 0.021). Compared to placebo, lumbar spine and total hip areal bone mineral densities (aBMD) were lower in the semaglutide group after 52 weeks ((ETD lumbar spine -0.018 g/cm3 [95% CI -0.031 to -0.005]; p = 0.007); ETD total hip -0.020 g/cm2 ([95% CI -0.032 to -0.008]; p = 0.001). Treatment differences in femoral neck aBMD were not observed ([95% CI [-0.017 to 0.006]; p = 0.328). Further, body weight was lower in the semaglutide group than in the placebo group after 52 weeks (ETD -6.8 kg [95% CI -8.8 to -4.7]; p < 0.001). Thirty-one [97%] in the semaglutide group and 18 [56%] in the placebo group experienced at least one adverse event, including four serious events (two in each group). No episodes of hypoglycaemia or deaths were reported. Interpretation: In adults with increased fracture risk, semaglutide once weekly did not increase bone formation based on the bone formation marker P-PINP. The observed increase in bone resorption in the semaglutide group may be explained by the accompanying weight loss. Funding: Region of Southern Denmark, Novo Nordisk Foundation, and Gangsted Foundation. Novo Nordisk provided the investigational drug and placebo.

4.
Chem Sci ; 15(20): 7749-7756, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38784727

ABSTRACT

The non-benzenoid aromatic tropone ring is a structural motif of numerous microbial and plant natural products with potent bioactivities. In bacteria, tropone biosynthesis involves early steps of the widespread CoA-dependent phenylacetic acid (paa) catabolon, from which a shunt product is sequestered and surprisingly further utilized as a universal precursor for structurally and functionally diverse tropone derivatives such as tropodithietic acid or (hydroxy)tropolones. Here, we elucidate the biosynthesis of the antibiotic 3,7-dihydroxytropolone in Actinobacteria by in vitro pathway reconstitution using paa catabolic enzymes as well as dedicated downstream tailoring enzymes, including a thioesterase (TrlF) and two flavoprotein monooxygenases (TrlCD and TrlE). We furthermore mechanistically and structurally characterize the multifunctional key enzyme TrlE, which mediates an unanticipated ipso-substitution involving a hydroxylation and subsequent decarboxylation of the CoA-freed side chain, followed by ring oxidation to afford tropolone. This study showcases a remarkably efficient strategy for 3,7-dihydroxytropolone biosynthesis and illuminates the functions of the involved biosynthetic enzymes.

5.
J Antimicrob Chemother ; 79(4): 810-814, 2024 04 02.
Article in English | MEDLINE | ID: mdl-38366372

ABSTRACT

OBJECTIVES: An Escherichia coli isolate, WGS1363, showed resistance to piperacillin/tazobactam but susceptibility to cephalosporins and contained a previously unrecognized ß-lactamase, CTX-M-255, as the only acquired ß-lactamase. CTX-M-255 was identical to CTX-M-27 except for a G239S substitution. Here, we characterize the hydrolytic spectrum of CTX-M-255 and a previously reported ß-lactamase, CTX-M-178, also containing a G239S substitution and compare it to their respective parental enzymes, CTX-M-27 and CTX-M-15. METHODS: All ß-lactamase genes were expressed in E. coli TOP10 and MICs to representative ß-lactam-antibiotics were determined. Furthermore, blaCTX-M-15,  blaCTX-M-27, blaCTX-M-178 and blaCTX-M-255 with C-terminal His-tag fusions were affinity purified for enzyme kinetic assays determining Michaelis-Menten kinetic parameters against representative ß-lactam-antibiotics and IC50s of clavulanate, sulbactam, tazobactam and avibactam. RESULTS: TOP10-transformants expressing blaCTX-M-178 and blaCTX-M-255 showed resistance to penicillin/ß-lactamase combinations and susceptibility to cephalothin and cefotaxime in contrast to transformants expressing blaCTX-M-15 and blaCTX-M-27. Determination of enzyme kinetic parameters showed that CTX-M-178 and CTX-M-255 both lacked hydrolytic activity against cephalosporins and showed impaired hydrolytic efficiency against penicillin antibiotics compared to their parental enzymes. Both enzymes appeared more active against piperacillin compared to benzylpenicillin and ampicillin. Compared to their parental enzymes, IC50s of ß-lactamase-inhibitors were increased more than 1000-fold for CTX-M-178 and CTX-M-255. CONCLUSIONS: CTX-M-178 and CTX-M-255, both containing a G239S substitution, conferred resistance to piperacillin/tazobactam and may be characterized as inhibitor-resistant CTX-M ß-lactamases. Inhibitor resistance was accompanied by loss of activity against cephalosporins and monobactams. These findings add to the necessary knowledge base for predicting antibiotic susceptibility from genotypic data.


Subject(s)
Anti-Bacterial Agents , beta-Lactamase Inhibitors , beta-Lactamase Inhibitors/pharmacology , Anti-Bacterial Agents/pharmacology , Escherichia coli , beta-Lactamases/genetics , Penicillins/pharmacology , Cephalosporins/pharmacology , Tazobactam/pharmacology , Piperacillin/pharmacology , Monobactams , Piperacillin, Tazobactam Drug Combination , Microbial Sensitivity Tests
6.
Nat Commun ; 15(1): 485, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38212305

ABSTRACT

Single-molecule magnets are among the most promising platforms for achieving molecular-scale data storage and processing. Their magnetisation dynamics are determined by the interplay between electronic and vibrational degrees of freedom, which can couple coherently, leading to complex vibronic dynamics. Building on an ab initio description of the electronic and vibrational Hamiltonians, we formulate a non-perturbative vibronic model of the low-energy magnetic degrees of freedom in monometallic single-molecule magnets. Describing their low-temperature magnetism in terms of magnetic polarons, we are able to quantify the vibronic contribution to the quantum tunnelling of the magnetisation, a process that is commonly assumed to be independent of spin-phonon coupling. We find that the formation of magnetic polarons lowers the tunnelling probability in both amorphous and crystalline systems by stabilising the low-lying spin states. This work, thus, shows that spin-phonon coupling subtly influences magnetic relaxation in single-molecule magnets even at extremely low temperatures where no vibrational excitations are present.

7.
Laryngorhinootologie ; 103(1): 17-24, 2024 01.
Article in German | MEDLINE | ID: mdl-38086413

ABSTRACT

At the beginning of 2023, there have been significant changes to the regulations for outpatient surgery in Germany, which were set out in a trilateral self-administration agreement between the umbrella association of statutory health insurance companies, the German Hospital Association and the Federal Association of Statutory Health Insurance Physicians. Among other things, a catalog stated circumstances under which an operation should not be carried out on an outpatient basis or should only be carried out with doubt. This catalog explains the patient's age: up to the first year of life, inpatient performance of a service can be justified. This formulation in itself means that children from one year of age on should regularly undergo outpatient surgery.In the german scientific societies for otolaryngology, head and neck surgery as well as for anesthesiology and intensive care medicine, doubts arose as to whether this age limit could also be scientifically justified for operations in the throat such as adenotomy or tonsillotomy.A search was carried out in international guidelines and in the international literature and the statements were evaluated. The results of this literature search were discussed with representatives of the Pediatric Otorhinolaryngology Working Group (AG PädHNO) of the German Society for Otorhinolaryngology, Head and Neck Surgery (DGHNO-KHC) and the scientific working group for pediatric anesthesia (WAKKA) of the German Society for Anesthesiology and Intensive Care Medicine (DGAI) in conferences.The consensus revealed that a strict age limit of the first year of life is not appropriate for the outpatient performance of adenotomies and tonsillotomies. First of all, specifying a strict age limit is questionable because, regardless of age, a number of other medical and social factors influence the responsible performance of outpatient operations. Furthermore, the age limit of one year is not considered appropriate in view of literature, guidelines and practical experience in the international area. The assessment of the literature and the consideration of the implementation in the international area make an age limit in the range of 2-3 years seem more appropriate.This review provides the responsible doctors with a variety of insights, aspects and arguments so that they can make their decision to carry out these operations on an outpatient or inpatient basis appropriately and responsibly.


Subject(s)
Outpatients , Humans , Child , Child, Preschool , Germany
8.
Biol Lett ; 19(11): 20230151, 2023 11.
Article in English | MEDLINE | ID: mdl-37964575

ABSTRACT

The effect of temperature on ectothermic organisms in the context of climate change has long been considered in isolation (i.e. as a single driver). This is challenged by observations demonstrating that temperature-dependent growth is correlated to further factors. However, little is known how the chronobiological history of an organism reflected in its adaptation to re-occurring cyclic patterns in its environment (e.g. annual range of photoperiods in its habitat) and biotic interactions with its microbiome, contribute to shaping its realized niche. To address this, we conducted a full-factorial microcosm multi-stressor experiment with the marine diatoms Thalassiosira gravida (polar) and Thalassiosira rotula (temperate) across multiple levels of temperature (4°C; 9°C; 13.5°C) and photoperiod (4 h; 16 h; 24 h), both in the presence or absence of their microbiomes. While temperature-dependent growth of the temperate diatom was constrained by short and long photoperiods, the polar diatom coped with a 24 h photoperiod up to its thermal optimum (9°C). The algal microbiomes particularly supported host growth at the margins of their respective fundamental niches except for the combination of the warmest temperature tested at 24 h photoperiod. Overall, this study demonstrates that temperature tolerances may have evolved interactively and that the mutualistic effect of the microbiome can only be determined once the multifactorial abiotic niche is defined.


Subject(s)
Diatoms , Microbiota , Photoperiod , Climate Change , Temperature
9.
J Am Chem Soc ; 2023 Nov 02.
Article in English | MEDLINE | ID: mdl-37917936

ABSTRACT

Molecular materials are poised to play a significant role in the development of future optoelectronic and quantum technologies. A crucial aspect of these areas is the role of spin-phonon coupling and how it facilitates energy transfer processes such as intersystem crossing, quantum decoherence, and magnetic relaxation. Thus, it is of significant interest to be able to accurately calculate the molecular spin-phonon coupling and spin dynamics in the condensed phase. Here, we demonstrate the maturity of ab initio methods for calculating spin-phonon coupling by performing a case study on a single-molecule magnet and showing quantitative agreement with the experiment, allowing us to explore the underlying origins of its spin dynamics. This feat is achieved by leveraging our recent developments in analytic spin-phonon coupling calculations in conjunction with a new method for including the infinite electrostatic potential in the calculations. Furthermore, we make the first ab initio determination of phonon lifetimes and line widths for a molecular magnet to prove that the commonplace Born-Markov assumption for the spin dynamics is valid, but such "exact" phonon line widths are not essential to obtain accurate magnetic relaxation rates. Calculations using this approach are facilitated by the open-source packages we have developed, enabling cost-effective and accurate spin-phonon coupling calculations on molecular solids.

10.
Environ Microbiol ; 25(11): 2481-2497, 2023 11.
Article in English | MEDLINE | ID: mdl-37553090

ABSTRACT

Hydrothermal systems form at divergent and convergent boundaries of lithospheric plates and within plates due to weakened crust and mantle plumes, playing host to diverse microbial ecosystems. Little is known of how differences in tectonic setting influence the geochemical and microbial compositions of these hydrothermal ecosystems. Here, coordinated geochemical and microbial community analyses were conducted on 87 high-temperature (>65°C) water and sediment samples from hot springs in Yellowstone National Park, Wyoming, USA (n = 41; mantle plume setting), Iceland (n = 41, divergent boundary), and Japan (n = 5; convergent boundary). Region-specific variation in geochemistry and sediment-associated 16S rRNA gene amplicon sequence variant (ASV) composition was observed, with 16S rRNA gene assemblages being nearly completely distinguished by region and pH being the most explanatory parameter within regions. Several low abundance ASVs exhibited cosmopolitan distributions across regions, while most high-abundance ASVs were only identified in specific regions. The presence of some cosmopolitan ASVs across regions argues against dispersal limitation primarily shaping the distribution of taxa among regions. Rather, the results point to local tectonic and geologic characteristics shaping the geochemistry of continental hydrothermal systems that then select for distinct microbial assemblages. These results provide new insights into the co-evolution of hydrothermal systems and their microbial communities.


Subject(s)
Hot Springs , Microbiota , Hot Springs/chemistry , RNA, Ribosomal, 16S/genetics , Water , Japan , Phylogeny
11.
Diabetes Obes Metab ; 25(11): 3235-3247, 2023 11.
Article in English | MEDLINE | ID: mdl-37503747

ABSTRACT

AIM: To investigate whether sodium-glucose cotransporter-2 (SGLT2) inhibitor use as compared to dipeptidyl peptidase-4 (DPP-4) inhibitor use as add-on to metformin is associated with the risk of any fracture or major osteoporotic fractures (MOFs). METHODS: A cohort study using the Clinical Practice Research Datalink (CPRD) Aurum database was conducted. All patients aged 18 years and older with a first-ever prescription for a DPP-4 inhibitor or an SGLT2 inhibitor as add-on to metformin between January 1, 2013 and June 30, 2020 were selected. Patients starting with SGLT2 inhibitors were matched (up to 1:3) on propensity scores to patients starting with DPP-4 inhibitors. Propensity scores were calculated based on sex, age, body mass index, comorbidities, comedication and lifestyle factors. Cox proportional hazard models were used to estimate the risk of fracture with SGLT2 inhibitor use as compared to DPP-4 inhibitor use. RESULTS: A total of 13 807 SGLT2 inhibitor users (age 55.4 ± 10.6 years, 36.7% female) were included in this study, matched with 28 524 DPP-4 inhibitor users (age 55.4 ± 8.0 years, 36.4% female). The risk of any fracture with current SGLT2 inhibitor use was similar compared with current DPP-4 inhibitor use (adjusted hazard ratio [aHR] 1.09, 95% confidence interval [CI] 0.91-1.31), as was the risk of MOFs (aHR 0.89, 95% CI 0.64-1.22) and the risk of fractures at any of the individual MOF sites. Additionally, no association was found with duration of SGLT2 inhibitor use (longest duration >811 days) for any of the individual SGLT2 inhibitor agents, or after stratification by sex and age. CONCLUSION: Use of SGLT2 inhibitors was not associated with the risk of any fracture, MOFs or fracture at the individual MOF sites when compared to DPP-4 inhibitor use.


Subject(s)
Diabetes Mellitus, Type 2 , Dipeptidyl-Peptidase IV Inhibitors , Fractures, Bone , Metformin , Sodium-Glucose Transporter 2 Inhibitors , Female , Humans , Male , Cohort Studies , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/chemically induced , Dipeptidyl-Peptidase IV Inhibitors/adverse effects , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/metabolism , Fractures, Bone/epidemiology , Fractures, Bone/prevention & control , Fractures, Bone/chemically induced , Glucose/therapeutic use , Hypoglycemic Agents/adverse effects , Metformin/adverse effects , Retrospective Studies , Sodium , Sodium-Glucose Transporter 2 Inhibitors/adverse effects
12.
Chem Soc Rev ; 52(14): 4567-4585, 2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37377351

ABSTRACT

Electron-phonon coupling is important in many physical phenomena, e.g. photosynthesis, catalysis and quantum information processing, but its impacts are difficult to grasp on the microscopic level. One area attracting wide interest is that of single-molecule magnets, which is motivated by searching for the ultimate limit in the miniaturisation of binary data storage media. The utility of a molecule to store magnetic information is quantified by the timescale of its magnetic reversal processes, also known as magnetic relaxation, which is limited by spin-phonon coupling. Several recent accomplishments of synthetic organometallic chemistry have led to the observation of molecular magnetic memory effects at temperatures above that of liquid nitrogen. These discoveries have highlighted how far chemical design strategies for maximising magnetic anisotropy have come, but have also highlighted the need to characterise the complex interplay between phonons and molecular spin states. The crucial step is to make a link between magnetic relaxation and chemical motifs, and so be able to produce design criteria to extend molecular magnetic memory. The basic physics associated with spin-phonon coupling and magnetic relaxation was outlined in the early 20th century using perturbation theory, and has more recently been recast in the form of a general open quantum systems formalism and tackled with different levels of approximations. It is the purpose of this Tutorial Review to introduce the topics of phonons, molecular spin-phonon coupling, and magnetic relaxation, and to outline the relevant theories in connection with both the traditional perturbative texts and the more modern open quantum systems methods.

13.
J Am Chem Soc ; 145(25): 13632-13639, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37327086

ABSTRACT

Anisotropy in the magnetic susceptibility strongly influences the paramagnetic shifts seen in nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) experiments. A previous study on a series of C3-symmetric prototype MRI contrast agents showed that their magnetic anisotropy was highly sensitive to changes in molecular geometry and concluded that changes in the average angle between the lanthanide-oxygen (Ln-O) bonds and the molecular C3 axis due to solvent interactions had a significant impact on the magnetic anisotropy and, consequently, the paramagnetic shift. However, this study, like many others, was predicated on an idealized C3-symmetric structural model, which may not be representative of the dynamic structure in solution at the single-molecule level. Here, we address this by using ab initio molecular dynamics simulations to simulate how the molecular geometry, in particular the angles between the Ln-O bonds and the pseudo-C3 axis, evolves over time in the solution, mimicking typical experimental conditions. We observe large-amplitude oscillations in the O-Ln-C̃3 angles, and complete active space self-consistent field spin-orbit calculations show that this leads to similarly large oscillations in the pseudocontact (dipolar) paramagnetic NMR shifts. The time-averaged shifts show good agreement with experimental measurements, while the large fluctuations suggest that an idealized structure provides an incomplete description of the solution dynamics. Our observations have significant implications for modeling the electronic and nuclear relaxation times in this and other systems where the magnetic susceptibility is exquisitely sensitive to the molecular structure.

14.
World J Surg ; 47(7): 1704-1710, 2023 07.
Article in English | MEDLINE | ID: mdl-37133808

ABSTRACT

OBJECTIVES: Acute cholecystitis is one of the most common surgical presentations in Australia and increases with age. Guidelines recommend early laparoscopic cholecystectomy (within 7 days), as it results in shorter length of stay, reduced costs and readmission rates. Despite this, there is a perception that early cholecystectomy may result in higher morbidity and conversion to open surgery in older patients. Our objective is to report the proportion of early versus delayed cholecystectomy in older patients in New South Wales (NSW), Australia, and to compare health outcomes and factors influencing variation. DESIGN: This is a retrospective population-based cohort study of all cholecystectomies for primary acute cholecystitis in NSW residents aged >50, between 2009 and 2019. The primary outcome was the proportion of early versus delayed cholecystectomy. We used multilevel multivariable logistic regression analyses adjusted for age, sex, comorbidities, insurance status, socio-economic status and hospital characteristics. RESULTS: A high rate (85%) of the 47,478 cholecystectomies in older patients were performed within 7 days of admission. Delayed surgery was associated with increasing age and comorbidity, male sex, Medicare-only insurance and surgery in low- or medium-volume centres. Early surgery was associated with shorter overall length of stay, fewer readmissions, less conversion to open surgery and lower bile duct injury rates. CONCLUSION: A high proportion of adults with cholecystitis are undergoing early cholecystectomy in NSW. Our results support the efficacy of early cholecystectomy in older patients and identify potentially modifiable factors relevant to health care professionals and policymakers.


Subject(s)
Cholecystectomy, Laparoscopic , Cholecystitis, Acute , Adult , Humans , Male , Aged , Retrospective Studies , Cohort Studies , National Health Programs , Cholecystectomy/methods , Cholecystectomy, Laparoscopic/methods , Cholecystitis, Acute/surgery , Length of Stay , Treatment Outcome
15.
[Update 2022: interdisciplinary statement on airway management with supraglottic airway devices in pediatric emergency medicine-The laryngeal mask is and remains state of the art : Joint statement of the Institute for Emergency Medicine and Medicine Management (INM), the University Clinic Munich, LMU Munich, Germany, the Working Group for Pediatric Critical Care and Emergency Medicine of the German Interdisciplinary Society for Critical Care and Emergency Medicine (DIVI), the Medical Directors of Emergency Medical Services in Bavaria (ÄLRD), the Scientific Working Group for Pediatric Anesthesia (WAKKA) of the German Society for Anesthesiology and Intensive Care Medicine (DGAI), the Scientific Working Group for Emergency Medicine of the German Society for Anesthesiology and Intensive Care Medicine (DGAI) and the Society of Neonatology and Pediatric Critical Care Medicine (GNPI)]. / Update 2022: Interdisziplinäre Stellungnahme zum Atemwegsmanagement mit supraglottischen Atemwegshilfen in der Kindernotfallmedizin ­ die Larynxmaske ist und bleibt State of the Art : Gemeinsame Stellungnahme des Instituts für Notfallmedizin und Medizinmanagement (INM), Klinikum der Universität München, der Sektion Pädiatrische Intensiv- und Notfallmedizin der Deutschen Interdisziplinären Vereinigung für Intensiv- und Notfallmedizin (DIVI), des Ärztlicher Leiter Rettungsdienst Bayern (ÄLRD Bayern), des Wissenschaftlichen Arbeitskreises Kinderanästhesie (WAKKA) der Deutschen Gesellschaft für Anästhesiologie und Intensivmedizin (DGAI), des Wissenschaftlichen Arbeitskreises Notfallmedizin der Deutschen Gesellschaft für Anästhesiologie und Intensivmedizin (DGAI) und der Gesellschaft für Neonatologie und Pädiatrische Intensivmedizin (GNPI).
Anaesthesiologie ; 72(6): 425-432, 2023 06.
Article in German | MEDLINE | ID: mdl-37222766

ABSTRACT

BACKGROUND: Airway management with supraglottic airway devices (SGA) in life-threatening emergencies in children is increasingly being used. Different specifications of laryngeal masks (LM) and the laryngeal tube (LT) are commonly used devices for this purpose. We present a literature review and interdisciplinary consensus statement of different societies on the use of SGA in pediatric emergency medicine. MATERIAL AND METHODS: Literature review in the PubMed database and classification of studies according to the criteria of the Oxford Centre for Evidence-based Medicine. Levels and consensus finding within the group of authors. RESULTS: The evidence for successful applications of the various types of LM is significantly higher than for LT application. Reported smaller series of successful applications of LT are currently limited to selected research groups and centers. Especially for children below 10 kg body weight there currently exists insufficient evidence for the successful application of the LT and therefore its routine use cannot be recommended. SGAs used for emergencies should have a gastric drainage possibility. DISCUSSION: Considering the scientific data and the large clinical experience with the LM in medical routine and emergency situations in children currently only the LM can be recommended for alternative (i.e., non-intubation) emergency airway management in children. If alternative airway management is part of a local emergency strategy, the LM should be provided in all pediatric sizes (1, 1½, 2, 2½, 3) for out of hospital use and in hospital emergency use and all users should regularly be trained in its application.


Subject(s)
Anesthesia , Anesthesiology , Emergency Medical Services , Emergency Medicine , Laryngeal Masks , Neonatology , Pediatric Emergency Medicine , Physician Executives , Child , Humans , Intubation, Intratracheal , Emergencies , Universities , Airway Management , Critical Care , Germany
16.
ACS Chem Neurosci ; 14(9): 1622-1630, 2023 05 03.
Article in English | MEDLINE | ID: mdl-37043174

ABSTRACT

A fundamental concept in neuroscience is the transmission of information between neurons via neurotransmitters, -modulators, and -peptides. For the past decades, the gold standard for measuring neurochemicals in awake animals has been microdialysis (MD). The emergence of genetically encoded fluorescence-based biosensors, as well as in vivo optical techniques such as fiber photometry (FP), has introduced technologically distinct means of measuring neurotransmission. To directly compare MD and FP, we performed concurrent within-animal recordings of extracellular dopamine (DA) in the dorsal striatum (DS) before and after administration of amphetamine in awake, freely behaving mice expressing the dopamine sensor dLight1.3b. We show that despite temporal differences, MD- and FP-based readouts of DA correlate well within mice. Down-sampling of FP data showed temporal correlation to MD data, with less variance observed using FP. We also present evidence that DA fluctuations periodically reach low levels, and naïve animals have rapid, predrug DA dynamics measured with FP that correlate to the subsequent pharmacodynamics of amphetamine as measured with MD and FP.


Subject(s)
Amphetamine , Dopamine , Mice , Animals , Amphetamine/pharmacology , Microdialysis/methods , Corpus Striatum , Synaptic Transmission
17.
Scand J Public Health ; : 14034948231159464, 2023 Apr 06.
Article in English | MEDLINE | ID: mdl-37026179

ABSTRACT

AIMS: (a) To investigate support for caregivers of people diagnosed with stroke, cancer, chronic obstructive pulmonary disease (COPD), dementia, or heart disease provided across healthcare settings in Denmark; (b) to assess differences in caregiver support across diagnoses and settings. METHODS: A cross-sectional nationwide survey among professionals representing healthcare settings at municipalities (n = 479) and hospital wards and outpatient clinics (n = 425). The survey assessed identification of caregivers and support initiatives. RESULTS: The response rate was 81% for municipalities and 49% for hospitals. Identification of caregivers was frequent in dementia care (81% and 100%) and less frequent in COPD care (58% and 64%) in municipalities and hospitals, respectively. Caregiver support differed significantly across diagnoses within municipalities (p = 0.009) and hospitals (p < 0.001). Systematic identification of vulnerable caregivers was <25% for all diagnoses except dementia. The most common support initiatives involving caregivers were primarily aimed at the ill person and included guidance about the disease and consequences for everyday life and lifestyle changes. Caregivers were least involved in support initiatives addressing physical training, work retention, sexuality, or cohabitation. CONCLUSIONS: Disparities and significant differences across diagnoses exist in the identification of caregivers and the provision of support initiatives. Support initiatives involving caregivers primarily targeted patients. Future studies should investigate how caregivers' needs can be met across different diagnoses and healthcare settings and investigate potential changes in caregivers' needs during disease trajectories. In clinical practice, identification of vulnerable caregivers should be a major focus, and disease-specific clinical guidelines may be required to ensure sufficient support for caregivers.

18.
J Am Chem Soc ; 145(16): 9152-9163, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37043770

ABSTRACT

Here, we report the synthesis of two new sets of dibismuth-bridged rare earth molecules. The first series contains a bridging diamagnetic Bi22- anion, (Cp*2RE)2(µ-η2:η2-Bi2), 1-RE (where Cp* = pentamethylcyclopentadienyl; RE = Gd (1-Gd), Tb (1-Tb), Dy (1-Dy), Y (1-Y)), while the second series comprises the first Bi23- radical-containing complexes for any d- or f-block metal ions, [K(crypt-222)][(Cp*2RE)2(µ-η2:η2-Bi2•)]·2THF (2-RE, RE = Gd (2-Gd), Tb (2-Tb), Dy (2-Dy), Y (2-Y); crypt-222 = 2.2.2-cryptand), which were obtained from one-electron reduction of 1-RE with KC8. The Bi23- radical-bridged terbium and dysprosium congeners, 2-Tb and 2-Dy, are single-molecule magnets with magnetic hysteresis. We investigate the nature of the unprecedented lanthanide-bismuth and bismuth-bismuth bonding and their roles in magnetic communication between paramagnetic metal centers, through single-crystal X-ray diffraction, ultraviolet-visible/near-infrared (UV-vis/NIR) spectroscopy, SQUID magnetometry, DFT and multiconfigurational ab initio calculations. We find a πz* ground SOMO for Bi23-, which has isotropic spin-spin exchange coupling with neighboring metal ions of ca. -20 cm-1; however, the exchange coupling is strongly augmented by orbitally dependent terms in the anisotropic cases of 2-Tb and 2-Dy. As the first examples of p-block radicals beneath the second row bridging any metal ions, these studies have important ramifications for single-molecule magnetism, main group element, rare earth metal, and coordination chemistry at large.

19.
Med Cannabis Cannabinoids ; 6(1): 21-31, 2023.
Article in English | MEDLINE | ID: mdl-36814687

ABSTRACT

Introduction: Treatment with cannabis extracts for a variety of diseases has gained popularity. However, differences in herb-drug interaction potential of extracts from different plant sources are poorly understood. In this study, we provide a characterization of cannabis extracts prepared from four cannabis chemotypes and an in vitro assessment of their Cytochrome P450 (CYP)-mediated herb-drug interaction profiles. Methods: Plant extracts were either commercially obtained or prepared using ethanol as solvent, followed by overnight decarboxylation in a reflux condenser system. The extracts were characterized for their cannabinoid content using NMR and HPLC-PDA-ELSD-ESIMS. CYP inhibition studies with the cannabis extracts and pure cannabinoids (tetrahydrocannabinol [THC] and cannabidiol [CBD]) were performed using pooled, mixed gender human liver microsomes. Tolbutamide and testosterone were used as specific substrates to assess the inhibitory potential of the extracts on CYP2C9 and CYP3A4, and the coumarinic oral anticoagulants warfarin, phenprocoumon, and acenocoumarol were studied as model compounds since in vivo herb-drug interactions have previously been reported for this compound class. Results: In accordance with the plant chemotypes, two extracts were rich in THC and CBD (at different proportions); one extract contained mostly CBD and the other mostly cannabigerol (CBG). Residual amounts of the corresponding acids were found in all extracts. The extracts with a single major cannabinoid (CBD or CBG) inhibited CYP2C9- and CYP3A4-mediated metabolism stronger than the extracts containing both major cannabinoids (THC and CBD). The inhibition of CYP3A4 and CYP2C9 by the extract containing mostly CBD was comparable to their inhibition by pure CBD. In contrast, the inhibitory potency of extracts containing both THC and CBD did not correspond to the combined inhibitory potency of pure THC and CBD. Although being structural analogs, the three coumarin derivatives displayed major differences in their herb-drug interaction profiles with the cannabis extracts and the pure cannabinoids. Conclusion: Despite the fact that cannabinoids are the major components in ethanolic, decarboxylated cannabis extracts, it is difficult to foresee their herb-drug interaction profiles. Our in vitro data and the literature-based evidence on in vivo interactions indicate that cannabis extracts should be used cautiously when co-administered with drugs exhibiting a narrow therapeutic window, such as coumarinic anticoagulants, regardless of the cannabis chemotype used for extract preparation.

20.
Proc Natl Acad Sci U S A ; 120(7): e2215230120, 2023 02 14.
Article in English | MEDLINE | ID: mdl-36749722

ABSTRACT

The dorsal (DS) and ventral striatum (VS) receive dopaminergic projections that control motor functions and reward-related behavior. It remains poorly understood how dopamine release dynamics across different temporal scales in these regions are coupled to behavioral outcomes. Here, we employ the dopamine sensor dLight1.3b together with multiregion fiber photometry and machine learning-based analysis to decode dopamine dynamics across the striatum during self-paced exploratory behavior in mice. Our data show a striking coordination of rapidly fluctuating signal in the DS, carrying information across dopamine levels, with a slower signal in the VS, consisting mainly of slow-paced transients. Importantly, these release dynamics correlated with discrete behavioral motifs, such as turns, running, and grooming on a subsecond-to-minute time scale. Disruption of dopamine dynamics with cocaine caused randomization of action selection sequencing and disturbance of DS-VS coordination. The data suggest that distinct dopamine dynamics of DS and VS jointly encode behavioral sequences during unconstrained activity with DS modulating the stringing together of actions and VS the signal to initiate and sustain the selected action.


Subject(s)
Cocaine , Ventral Striatum , Mice , Animals , Dopamine , Reward
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