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  1. Article ; Online: Selective Schiff base formation via gas-phase ion/ion reactions to enable differentiation of isobaric lipids in imaging mass spectrometry.

    Diao, Xizheng / Ellin, Nicholas R / Prentice, Boone M

    Analytical and bioanalytical chemistry

    2023  Volume 415, Issue 18, Page(s) 4319–4331

    Abstract: ... their cellular functions. Failure to resolve isobaric compounds (e.g., via high mass resolution or ... This process is demonstrated using the isobaric lipids [PS 40:6 - H] ...

    Abstract The separation and identification of lipids in complex mixtures are critical to deciphering their cellular functions. Failure to resolve isobaric compounds (e.g., via high mass resolution or tandem mass spectrometry) can result in incorrect identifications in mass spectrometry experiments. In imaging mass spectrometry, unresolved peaks can also result in composite images of multiple compounds, giving inaccurate depictions of molecular distributions. Gas-phase ion/ion reactions can be used to selectively react with specific chemical functional groups on a target analyte, thereby extracting it from a complex mixture and shifting its m/z value to an unobstructed region of the mass range. Herein, we use selective Schiff base formation via a novel charge inversion ion/ion reaction to purify phosphatidylserines from other isobaric (i.e., same nominal mass) lipids and reveal their singular distributions in imaging mass spectrometry. The selective Schiff base formation between singly deprotonated phosphatidylserine (PS) lipid anions and doubly charged N,N,N',N'-tetramethyl-N,N'-bis(6-oxohexyl)hexane-1,6-diaminium (TMODA) cations is performed using a modified commercial dual source hybrid Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. This process is demonstrated using the isobaric lipids [PS 40:6 - H]
    MeSH term(s) Schiff Bases/chemistry ; Anions ; Cations ; Tandem Mass Spectrometry ; Lipids
    Chemical Substances Schiff Bases ; Anions ; Cations ; Lipids
    Language English
    Publishing date 2023-01-11
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 201093-8
    ISSN 1618-2650 ; 0016-1152 ; 0372-7920
    ISSN (online) 1618-2650
    ISSN 0016-1152 ; 0372-7920
    DOI 10.1007/s00216-023-04523-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Epidemiology of Gram-negative bacteria during coronavirus disease 2019. What is the real pandemic?

    Brink, Adrian J / Richards, Guy / Tootla, Hafsah / Prentice, Elizabeth

    Current opinion in infectious diseases

    2022  Volume 35, Issue 6, Page(s) 595–604

    Abstract: Purpose of review: Bacterial infections play a key role in hospital outcomes during the coronavirus disease 2019 (COVID-19) pandemic. Nonetheless, the global impact on the epidemiology of Gram-negative bacteria (GNB) and antibiotic resistance has not ... ...

    Abstract Purpose of review: Bacterial infections play a key role in hospital outcomes during the coronavirus disease 2019 (COVID-19) pandemic. Nonetheless, the global impact on the epidemiology of Gram-negative bacteria (GNB) and antibiotic resistance has not been clearly established.
    Recent findings: Multiple limitations exist in the current literature, in that substantial variability was observed with regard to methodology. Notwithstanding the heterogeneity, the evidence suggests that the COVID-19 pandemic had a substantial negative impact on global epidemiology with an increase in hospital-onset infections, associated with GNB. Similarly, an alarming increase in resistant GNB compared to prepandemic rates, was apparent. This was most evident for carbapenemase-producing Klebsiella pneumoniae (bloodstream infections), carbapenem-resistant Pseudomonas aeruginosa (ventilator-associated pneumonia), and carbapenem-resistant Acinetobacter baumannii (all infections). Significant variations were most apparent in the large, system-wide regional or national comparative assessments, vs. single-centre studies. Categorizing concurrent bacteria as co- or secondary-infections may be paramount to optimize standard of care.
    Summary: The data from most studies signal the probability that COVID-19 accelerated resistance. However, multiple limitations intrinsic to interpretation of current COVID-19 data, prevents accurately quantifying collateral damage on the global epidemiology and antibiotic resistance amongst GNB. It is likely to be substantial and renewed efforts to limit further increases is warranted.
    MeSH term(s) Humans ; COVID-19/epidemiology ; Pandemics ; Anti-Bacterial Agents/pharmacology ; Anti-Bacterial Agents/therapeutic use ; Gram-Negative Bacteria ; Carbapenems ; Gram-Negative Bacterial Infections/drug therapy ; Drug Resistance, Multiple, Bacterial
    Chemical Substances Anti-Bacterial Agents ; Carbapenems
    Language English
    Publishing date 2022-08-03
    Publishing country United States
    Document type Review ; Journal Article
    ZDB-ID 645085-4
    ISSN 1473-6527 ; 1535-3877 ; 0951-7375 ; 1355-834X
    ISSN (online) 1473-6527 ; 1535-3877
    ISSN 0951-7375 ; 1355-834X
    DOI 10.1097/QCO.0000000000000864
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  3. Article ; Online: Postoperative opioid utilization associated with revision risk following primary shoulder arthroplasty.

    Singh, Anshuman / Chan, Priscilla H / Prentice, Heather A / Rao, Anita G

    Journal of shoulder and elbow surgery

    2020  Volume 30, Issue 5, Page(s) 1034–1041

    Abstract: Introduction: With a substantial increase in utilization of primary shoulder arthroplasty, it is important to understand risk factors that may signal early failure and need for revision. Recent studies have reported that sustained postoperative opioid ... ...

    Abstract Introduction: With a substantial increase in utilization of primary shoulder arthroplasty, it is important to understand risk factors that may signal early failure and need for revision. Recent studies have reported that sustained postoperative opioid use is associated with a higher revision risk after total hip or knee arthroplasty. In this study, we evaluated postoperative opioid utilization as a risk factor for revision after primary shoulder arthroplasty.
    Methods: We conducted a cohort study using data from a United States integrated health care system's Shoulder Arthroplasty Registry. Patients who had a primary elective shoulder arthroplasty were identified (2009-2017); those with cancer or who underwent other arthroplasty procedures (either shoulder, hip, or knee) within the preceding year were excluded. Cumulative daily opioid utilization during the first year postoperative, calculated as oral morphine equivalents (OME), was categorized into 3 exposure groups: high user (≥15 mg OME daily), moderate user (<15 mg OME daily), and no opioid use (reference group). The exposure window was stratified into 2 time periods: postoperative days 1-90 and postoperative days 91-360. Multivariable Cox proportional-hazards regression was used to evaluate the association between postoperative opioid use and aseptic revision risk.
    Results: The final study sample included 8325 shoulder arthroplasty procedures. Of these individuals, 3707 (45%) received some opioid within the 1 year before the index procedure. We failed to observe a difference in aseptic revision risk between opioid utilization in the first 90 days postoperatively, regardless of dose. After the first 90 days, a higher revision risk was observed for high opioid users compared with nonusers (hazard ratio = 1.62, 95% confidence interval = 1.10-2.41), and no association was observed for moderate users (hazard ratio = 1.25, 95% confidence interval = 0.82-1.91).
    Conclusions: We found a positive association between opioid consumption and aseptic revision risk after primary shoulder arthroplasty. This study cannot determine if opioids have a direct physiological cause that increases the risk of revision; rather it is likely that opioid consumption is a marker of chronic pain, poor function, and/or poor coping mechanisms. Further study is needed to determine if programs designed to decrease opioid use may impact revision risk after shoulder arthroplasty.
    MeSH term(s) Analgesics, Opioid/adverse effects ; Arthroplasty, Replacement, Knee/adverse effects ; Arthroplasty, Replacement, Shoulder/adverse effects ; Cohort Studies ; Humans ; Pain, Postoperative/drug therapy ; Pain, Postoperative/etiology ; Reoperation ; Retrospective Studies ; Risk Factors ; United States/epidemiology
    Chemical Substances Analgesics, Opioid
    Language English
    Publishing date 2020-08-29
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1170782-3
    ISSN 1532-6500 ; 1058-2746
    ISSN (online) 1532-6500
    ISSN 1058-2746
    DOI 10.1016/j.jse.2020.08.014
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Conference proceedings: Proceedings of the Seminar New Trends in the Treatment of Acute Leukaemia

    Prentice, H. G.

    20 - 22 September 1989, Dubrovnik, Yugoslavia

    (Bone marrow transplantation ; 4, Suppl. 3)

    1989  

    Institution European School of Oncology
    Event/congress Seminar New Trends in the Treatment of Acute Leukaemia (1989, Dubrovnik)
    Author's details ed. H. G. Prenice ... European School of Oncology
    Series title Bone marrow transplantation ; 4, Suppl. 3
    Collection
    Keywords Leukemia / therapy / congresses ; Akute Leukämie ; Therapie
    Subject Medizinische Behandlung ; Behandlung ; Krankenbehandlung ; Leukose
    Size 116 S. : graph. Darst.
    Publisher Macmillan
    Publishing place Basingstoke
    Publishing country Great Britain
    Document type Book ; Conference proceedings
    HBZ-ID HT003551248
    Database Catalogue ZB MED Medicine, Health

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  5. Article ; Online: Carbapenem-resistant

    Marais, Gert / Moodley, Clinton / Claassen-Weitz, Shantelle / Patel, Fadheela / Prentice, Elizabeth / Tootla, Hafsah / Nyakutira, Nyasha / Lennard, Katie / Reddy, Kessendri / Bamford, Colleen / Niehaus, Abraham / Whitelaw, Andrew / Brink, Adrian

    JAC-antimicrobial resistance

    2024  Volume 6, Issue 2, Page(s) dlae050

    Abstract: Background: The molecular epidemiology of carbapenem-resistant Enterobacterales in Cape Town remains largely unknown.: Objectives: This study aimed to describe the molecular epidemiology, resistome, virulome and mobilome of carbapenem-resistant : ... ...

    Abstract Background: The molecular epidemiology of carbapenem-resistant Enterobacterales in Cape Town remains largely unknown.
    Objectives: This study aimed to describe the molecular epidemiology, resistome, virulome and mobilome of carbapenem-resistant
    Methods: Eighty-five CRKP isolates from hospitalized patients underwent WGS as part of a prospective, multicentre, cross-sectional study, conducted between 1 November 2020 and 30 November 2022, across public-sector and private-sector hospitals in Cape Town, South Africa.
    Results: MLST revealed three novel types, ST6785, ST6786 and ST6787, while the most common were ST219, ST307, ST17, ST13 and ST2497. Different predominant clones were noted in each hospital. The most common carbapenemase gene was
    Conclusions: CRKP epidemiology in Cape Town reflects institutionally dominant, rather than regional, clones. The most prevalent carbapenemase gene was
    Language English
    Publishing date 2024-03-25
    Publishing country England
    Document type Journal Article ; Comment
    ISSN 2632-1823
    ISSN (online) 2632-1823
    DOI 10.1093/jacamr/dlae050
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Book: Infections in haematology

    Prentice, H. G.

    (CLINICS IN HAEMATOLOGY ; 13,3)

    1984  

    Series title CLINICS IN HAEMATOLOGY ; 13,3
    Clinics in haematology
    Collection Clinics in haematology
    Keywords HEMATOLOGIC DISEASES / COMPLICATIONS ; INFECTION / COMPLICATIONS
    Size S. 523-731
    Publisher Saunders
    Publishing place London
    Document type Book
    HBZ-ID HT002484829
    Database Catalogue ZB MED Medicine, Health

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  7. Article ; Online: Retraction Note: A constraint on historic growth in global photosynthesis due to increasing CO

    Keenan, T F / Luo, X / De Kauwe, M G / Medlyn, B E / Prentice, I C / Stocker, B D / Smith, N G / Terrer, C / Wang, H / Zhang, Y / Zhou, S

    Nature

    2022  Volume 606, Issue 7913, Page(s) 420

    Language English
    Publishing date 2022-05-30
    Publishing country England
    Document type Journal Article ; Retraction of Publication
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-022-04869-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Predictability of leaf traits with climate and elevation: a case study in Gongga Mountain, China.

    Xu, Huiying / Wang, Han / Prentice, I Colin / Harrison, Sandy P / Wang, Genxu / Sun, Xiangyang

    Tree physiology

    2021  Volume 41, Issue 8, Page(s) 1336–1352

    Abstract: Leaf mass per area (Ma), nitrogen content per unit leaf area (Narea), maximum carboxylation capacity (Vcmax) and the ratio of leaf-internal to ambient CO2 partial pressure (χ) are important traits related to photosynthetic function, and they show ... ...

    Abstract Leaf mass per area (Ma), nitrogen content per unit leaf area (Narea), maximum carboxylation capacity (Vcmax) and the ratio of leaf-internal to ambient CO2 partial pressure (χ) are important traits related to photosynthetic function, and they show systematic variation along climatic and elevational gradients. Separating the effects of air pressure and climate along elevational gradients is challenging due to the covariation of elevation, pressure and climate. However, recently developed models based on optimality theory offer an independent way to predict leaf traits and thus to separate the contributions of different controls. We apply optimality theory to predict variation in leaf traits across 18 sites in the Gongga Mountain region. We show that the models explain 59% of trait variability on average, without site- or region-specific calibration. Temperature, photosynthetically active radiation, vapor pressure deficit, soil moisture and growing season length are all necessary to explain the observed patterns. The direct effect of air pressure is shown to have a relatively minor impact. These findings contribute to a growing body of research indicating that leaf-level traits vary with the physical environment in predictable ways, suggesting a promising direction for the improvement of terrestrial ecosystem models.
    MeSH term(s) China ; Climate ; Ecosystem ; Photosynthesis ; Plant Leaves
    Language English
    Publishing date 2021-03-17
    Publishing country Canada
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 743341-4
    ISSN 1758-4469 ; 0829-318X
    ISSN (online) 1758-4469
    ISSN 0829-318X
    DOI 10.1093/treephys/tpab003
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Evidence for a short-lived resonance state in enzyme catalysis via rate-equation convolution.

    Steyn-Ross, Moira L / Steyn-Ross, D A / Prentice, Erica J / Walker, Emma J / Arcus, V L

    Physical review. E

    2023  Volume 107, Issue 6-1, Page(s) 64407

    Abstract: ... with a Gaussian temperature distribution g(T) to produce an exponentially modified Gaussian function h(T). To give ... for an Arrhenius-like transition from ground-state A to metastable-state B, and g(Θ) as the Gaussian distribution ...

    Abstract At the cellular level, all biological function relies on enzymes to provide catalytic acceleration of essential biochemical processes driving cellular metabolism. The enzyme is presumed to lower the activation energy barrier separating reactants from products, but the precise mechanism remains unresolved. Here we examine the temperature dependence of the enzyme-catalyzed dissociation of p-nitrophenyl-α-D-glucopyranoside (pNPG), a chromogenic analog for maltose, isomaltose, and sucrose disaccharide sugars, into p-nitrophenol (pNP) and glucose (monosaccharide). The enzymes of interest are the wild type and mutant forms of glucosidase MalL produced by the probiotic bacterium Bacillus subtilis. The per-enzyme production rates k(T) for the pNPG→ glucose reaction all show a characteristic temperature profile with an Arrhenius-like (approximately exponential) slow acceleration at low temperatures, rising through a point of inflexion to reach a maximum, then turning over to decline steeply towards zero production at high temperatures. This asymmetric profile is found to be well fitted by convolving an exponential growth function f(T) with a Gaussian temperature distribution g(T) to produce an exponentially modified Gaussian function h(T). To give a physical interpretation of the convolution components, we make the temperature mapping Θ≡T_{ref}-T where T_{ref} marks the temperature at which a given mutant becomes fully denatured (unfolded) and therefore inactive, then convert the convolution components to probability density functions which obey the convolution theorem of statistics. Working in Θ space, we identify f(Θ) as the density function for an Arrhenius-like transition from ground-state A to metastable-state B, and g(Θ) as the Gaussian distribution of offset-temperature fluctuations for the metastable state. By mapping the standard thermodynamic relations for temperature and energy fluctuations to the enzyme frame of reference, we are able to derive an expression for the lifetime for the metastable B state. For the 15 enzyme experiments, we obtain a mean value 〈Δt〉≳(29.0±1.3)×10^{-15}s, in remarkably good agreement with the ∼30-fs estimate for the period of glycosidic bond oscillations extracted from published infrared spectroscopy. We suggest that the metastable B state provides a low-energy target that has the effect of lowering the activation energy barrier by presenting an alternative axis for the reaction coordinate.
    MeSH term(s) Temperature ; Thermodynamics ; Catalysis ; Hot Temperature ; Glucose ; Kinetics
    Chemical Substances Glucose (IY9XDZ35W2)
    Language English
    Publishing date 2023-07-18
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2844562-4
    ISSN 2470-0053 ; 2470-0045
    ISSN (online) 2470-0053
    ISSN 2470-0045
    DOI 10.1103/PhysRevE.107.064407
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  10. Article ; Online: Long-term neuropsychological trajectories in children with epilepsy: does surgery halt decline?

    Eriksson, Maria H / Prentice, Freya / Piper, Rory J / Wagstyl, Konrad / Adler, Sophie / Chari, Aswin / Booth, John / Moeller, Friederike / Das, Krishna / Eltze, Christin / Cooray, Gerald / Perez Caballero, Ana / Menzies, Lara / McTague, Amy / Shavel-Jessop, Sara / Tisdall, Martin M / Cross, J Helen / Martin Sanfilippo, Patricia / Baldeweg, Torsten

    Brain : a journal of neurology

    2024  

    Abstract: ... in the time leading up to surgery (all p-values ≤ 0.001; e.g., βFSIQ = -1.9, SEFSIQ = 0.3, pFSIQ < 0.001 ... postoperative neuropsychological performance (e.g., rrb-FSIQ = 0.37, p < 0.001). These children continued ... to demonstrate improvements in neuropsychological functioning over the course of their long-term follow-up (e.g ...

    Abstract Neuropsychological impairments are common in children with drug-resistant epilepsy. It has been proposed that epilepsy surgery may alleviate these impairments by providing seizure freedom; however, findings from prior studies have been inconsistent. We mapped long-term neuropsychological trajectories in children before and after undergoing epilepsy surgery, to measure the impact of disease course and surgery on functioning. We performed a retrospective cohort study of 882 children who had undergone epilepsy surgery at Great Ormond Street Hospital (1990-2018). We extracted patient information and neuropsychological functioning - obtained from IQ tests (domains: Full-Scale IQ, Verbal IQ, Performance IQ, Working Memory, and Processing Speed) and tests of academic attainment (Reading, Spelling and Numeracy) - and investigated changes in functioning using regression analyses. We identified 500 children (248 females) who had undergone epilepsy surgery (median age at surgery = 11.9 years, interquartile range = [7.8,15.0]) and neuropsychology assessment. These children showed declines in all domains of neuropsychological functioning in the time leading up to surgery (all p-values ≤ 0.001; e.g., βFSIQ = -1.9, SEFSIQ = 0.3, pFSIQ < 0.001). Children lost on average one to four points per year, depending on the domain considered; 27-43% declined by 10 or more points from their first to their last preoperative assessment. At the time of presurgical evaluation, most children (46-60%) scored one or more standard deviations below the mean (<85) on the different neuropsychological domains; 37% of these met the threshold for intellectual disability (Full-Scale IQ < 70). On a group level, there was no change in performance from pre- to postoperative assessment on any of the domains (all p-values > 0.128). However, children who became seizure-free through surgery showed higher postoperative neuropsychological performance (e.g., rrb-FSIQ = 0.37, p < 0.001). These children continued to demonstrate improvements in neuropsychological functioning over the course of their long-term follow-up (e.g., βFSIQ = 0.9, SEFSIQ = 0.3, pFSIQ = 0.004). Children who had discontinued antiseizure medication (ASM) treatment at one-year follow-up showed an eight-to-13-point advantage in postoperative Working Memory, Processing Speed, and Numeracy, and greater improvements in Verbal IQ, Working Memory, Reading, and Spelling (all p-values < 0.034) over the postoperative period compared to children who were seizure-free and still receiving ASMs. In conclusion, by providing seizure freedom and the opportunity for ASM cessation, epilepsy surgery may not only halt but reverse the downward trajectory that children with drug-resistant epilepsy display in neuropsychological functioning. To halt this decline as soon as possible, or potentially prevent it from occurring in the first place, children with focal epilepsy should be considered for epilepsy surgery as early as possible after diagnosis.
    Language English
    Publishing date 2024-04-20
    Publishing country England
    Document type Journal Article
    ZDB-ID 80072-7
    ISSN 1460-2156 ; 0006-8950
    ISSN (online) 1460-2156
    ISSN 0006-8950
    DOI 10.1093/brain/awae121
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