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1.
Int J Sports Phys Ther ; 19(6): 724-734, 2024.
Article in English | MEDLINE | ID: mdl-38835988

ABSTRACT

Background: Repetitive application of high forces to the shoulder and scapular musculature during the pitching motion over the course of a collegiate baseball season may lead to changes in strength and increased fatigue, potentially predisposing pitching athletes to injury. The purpose of this study was to investigate periscapular strength profiles of Division I collegiate baseball players over the course of a season. Methods: This study was a retrospective data analysis of 18 Division I baseball pitchers. Isometric scapular plane abduction (scaption), external rotator, internal rotator, middle trapezius, and lower trapezius isometric strength was measured on throwing arm of each subject using a MicroFET 2 handheld dynamometer. Data were collected in a single session at the preseason, midseason, and postseason of the college baseball season, which spanned a five-month period. A repeated measures ANOVA was utilized to determine if there was a significant change in periscapular strength across the baseball season. Results: Over the three time-points, all strength values decreased for each muscle group, with decreases ranging from 3-14%. Changes in scaption strength values were statistically significant (p=0.018, partial eta squared =0.284) with an 8% reduction over the entire season, specifically with a 5% decline from mid-season to post-season. While external rotator, internal rotator, middle trapezius, and lower trapezius strength values all decreased over the course of the season (range 0.02kg to 1.8kg), these differences were not statistically significant. However, the middle trapezius strength value change (1.3kg loss) exceeded the minimal detectible change. Conclusion: Periscapular muscles in baseball pitchers diminish in strength over the course of a collegiate baseball season. Understanding strength changes over the course of a season may influence training and therapeutic interventions. Level of Evidence: 3b.

2.
Trends Plant Sci ; 28(5): 495-497, 2023 05.
Article in English | MEDLINE | ID: mdl-36935267

ABSTRACT

We consider the science, policy, and implementation (science-policy-society interface) issues around the agrifood system and the UK's transition to net zero. We conclude that agrifood policy should become more targeted, and the marriage of top-down and bottom-up approaches is key to co-create a pathway that is plausible for each stakeholder.

3.
Org Lett ; 24(49): 8986-8989, 2022 12 16.
Article in English | MEDLINE | ID: mdl-36454603

ABSTRACT

Notwithstanding recent developments in nickel-catalyzed C-O cross-coupling chemistry, such transformations of substituted phenols and (hetero)aryl chlorides with a useful reaction scope have yet to be reported. In this work, we disclose the results of catalyst screening that allowed the identification of PhPAd-DalPhos/NiCOD2 as an effective catalyst system under thermal conditions for the O-arylation of substituted phenols with chloropyridine-type electrophiles, leading to pyridyl-O-aryl frameworks that are found in active pharmaceutical ingredients.


Subject(s)
Nickel , Phenols , Catalysis , Chlorides
4.
Organometallics ; 41(19): 2662-2667, 2022 Oct 10.
Article in English | MEDLINE | ID: mdl-36249447

ABSTRACT

Herein we disclose the synthesis of sterically encumbered dialkylnickel(II) complexes bearing 2,9-dimethyl-1,10-phenanthroline ligands. A comparison with their unsubstituted analogues by both X-ray crystallography and theoretical calculations revealed significant distortions in their molecular structures. Eyring plots along with stoichiometric and photoexcitation studies revealed that sterically encumbered dialkylnickel(II) complexes enable facile C(sp 3)-C(sp 3) reductive elimination, thus offering an improved understanding of Ni catalysis.

5.
Chemistry ; 28(28): e202200764, 2022 May 16.
Article in English | MEDLINE | ID: mdl-35274772

ABSTRACT

We report on our successful development of the first metal-catalyzed mono-α-arylation of carbonyl compounds employing a soluble organic base. The scope of these Ni/DalPhos-catalyzed transformations encompasses a range of (hetero)aryl halides (Cl, Br, I) and phenol-derived electrophiles (sulfonates, carbonates, carbamates, sulfamates), including active pharmaceutical ingredients (chloroquine, clozapine), in combination with the typically problematic feedstock small molecule substrates acetone, dimethylacetamide, and for the first time with any metal catalyst/base, ethyl acetate.


Subject(s)
Nickel , Phenol , Catalysis , Nickel/chemistry , Solvents
6.
Angew Chem Int Ed Engl ; 61(13): e202200352, 2022 03 21.
Article in English | MEDLINE | ID: mdl-35085411

ABSTRACT

The C-N cross-coupling of (hetero)aryl (pseudo)halides with NH substrates employing nickel catalysts and organic amine bases represents an emergent strategy for the sustainable synthesis of (hetero)anilines. However, unlike protocols that rely on photoredox/electrochemical/reductant methods within NiI/III cycles, the reaction steps that comprise a putative Ni0/II C-N cross-coupling cycle for a thermally promoted catalyst system using organic amine base have not been elucidated. Here we disclose an efficient new nickel-catalyzed protocol for the C-N cross-coupling of amides and 2'-(pseudo)halide-substituted acetophenones, for the first time where the (pseudo)halide is chloride or sulfonate, which makes use of the commercial bisphosphine ligand PAd2-DalPhos (L4) in combination with an organic amine base/halide scavenger, leading to 4-quinolones. Room-temperature stoichiometric experiments involving isolated Ni0, I, and II species support a Ni0/II pathway, where the combined action of DBU/NaTFA allows for room-temperature amide cross-couplings.


Subject(s)
Amines , Nickel , 4-Quinolones , Amides , Amination , Catalysis
7.
Antimicrob Agents Chemother ; 65(7): e0006321, 2021 06 17.
Article in English | MEDLINE | ID: mdl-33972243

ABSTRACT

Infection caused by carbapenem-resistant (CR) organisms is a rising problem in the United States. While the risk factors for antibiotic resistance are well known, there remains a large need for the early identification of antibiotic-resistant infections. Using machine learning (ML), we sought to develop a prediction model for carbapenem resistance. All patients >18 years of age admitted to a tertiary-care academic medical center between 1 January 2012 and 10 October 2017 with ≥1 bacterial culture were eligible for inclusion. All demographic, medication, vital sign, procedure, laboratory, and culture/sensitivity data were extracted from the electronic health record. Organisms were considered CR if a single isolate was reported as intermediate or resistant. Patients with CR and non-CR organisms were temporally matched to maintain the positive/negative case ratio. Extreme gradient boosting was used for model development. In total, 68,472 patients met inclusion criteria, with 1,088 patients identified as having CR organisms. Sixty-seven features were used for predictive modeling. The most important features were number of prior antibiotic days, recent central venous catheter placement, and inpatient surgery. After model training, the area under the receiver operating characteristic curve was 0.846. The sensitivity of the model was 30%, with a positive predictive value (PPV) of 30% and a negative predictive value of 99%. Using readily available clinical data, we were able to create a ML model capable of predicting CR infections at the time of culture collection with a high PPV.


Subject(s)
Carbapenems , Machine Learning , Carbapenems/pharmacology , Humans , Predictive Value of Tests , Retrospective Studies , Risk Assessment
8.
Angew Chem Int Ed Engl ; 60(8): 4080-4084, 2021 Feb 19.
Article in English | MEDLINE | ID: mdl-33201556

ABSTRACT

The Ni-catalyzed N-arylation of ß-fluoroalkylamines with broad scope is reported for the first time. Use of the air-stable pre-catalyst (PAd2-DalPhos)Ni(o-tol)Cl allows for reactions to be conducted at room temperature (25 °C, NaOtBu), or by use of a commercially available dual-base system (100 °C, DBU/NaOTf), to circumvent decomposition of the N-(ß-fluoroalkyl)aniline product. The mild protocols disclosed herein feature broad (hetero)aryl (pseudo)halide scope (X=Cl, Br, I, and for the first time phenol-derived electrophiles), encompassing base-sensitive substrates and enantioretentive transformations, in a manner that is unmatched by any previously reported catalyst system.

9.
Brain Stimul ; 13(5): 1323-1332, 2020.
Article in English | MEDLINE | ID: mdl-32629028

ABSTRACT

BACKGROUND: Vagus nerve stimulation (VNS) modifies brain rhythms in the locus coeruleus (LC) via the solitary nucleus. Degeneration of the LC in Parkinson's disease (PD) is an early catalyst of the spreading neurodegenerative process, suggesting that stimulating LC output with VNS has the potential to modify disease progression. We previously showed in a lesion PD model that VNS delivered twice daily reduced neuroinflammation and motor deficits, and attenuated tyrosine hydroxylase (TH)-positive cell loss. OBJECTIVE: The goal of this study was to characterize the differential effects of three clinically-relevant VNS paradigms in a PD lesion model. METHODS: Eleven days after DSP-4 (N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine, noradrenergic lesion, administered systemically)/6-OHDA (6-hydroxydopamine, dopaminergic lesion, administered intrastriatally) rats were implanted with VNS devices, and received either low-frequency VNS, standard-frequency VNS, or high-frequency microburst VNS. After 10 days of treatment and behavioral assessment, rats were euthanized, right prefrontal cortex (PFC) was dissected for norepinephrine assessment, and the left striatum, bilateral substantia nigra (SN), and LC were sectioned for immunohistochemical detection of catecholamine neurons, α-synuclein, astrocytes, and microglia. RESULTS: At higher VNS frequencies, specifically microburst VNS, greater improvements occurred in motor function, attenuation of TH-positive cell loss in SN and LC, and norepinephrine concentration in the PFC. Additionally, higher VNS frequencies resulted in lower intrasomal α-synuclein accumulation and glial density in the SN. CONCLUSIONS: These data indicate that higher stimulation frequencies provided the greatest attenuation of behavioral and pathological markers in this PD model, indicating therapeutic potential for these VNS paradigms.


Subject(s)
Locomotion/physiology , Locus Coeruleus/metabolism , Parkinsonian Disorders/metabolism , Parkinsonian Disorders/therapy , Substantia Nigra/metabolism , Vagus Nerve Stimulation/methods , Animals , Locomotion/drug effects , Locus Coeruleus/drug effects , Male , Oxidopamine/toxicity , Parkinsonian Disorders/chemically induced , Rats , Rats, Long-Evans , Substantia Nigra/drug effects , Tyrosine 3-Monooxygenase/metabolism
10.
Angew Chem Int Ed Engl ; 59(23): 8952-8956, 2020 06 02.
Article in English | MEDLINE | ID: mdl-32162451

ABSTRACT

The development of Ni-catalyzed C-N cross-couplings of sulfonamides with (hetero)aryl chlorides is reported. These transformations, which were previously achievable only with Pd catalysis, are enabled by use of air-stable (L)NiCl(o-tol) pre-catalysts (L=PhPAd-DalPhos and PAd2-DalPhos), without photocatalysis. The collective scope of (pseudo)halide electrophiles (X=Cl, Br, I, OTs, and OC(O)NEt2 ) demonstrated herein is unprecedented for any reported catalyst system for sulfonamide C-N cross-coupling (Pd, Cu, Ni, or other). Preliminary competition experiments and relevant coordination chemistry studies are also presented.

12.
Healthc Q ; 19(1): 42-8, 2016.
Article in English | MEDLINE | ID: mdl-27133607

ABSTRACT

Communication gaps when patients transition from hospital to either home or community can be problematic. Partnership between Toronto Central Local Health Integration Network (TC LHIN) and OpenLab addressed this through the Patient-Oriented Discharge Summaries (PODS) project. From January through March 2015, eight hospital departments across Toronto came together to implement the PODS, a tool previously developed through a co-design process involving patients, caregivers and providers. This paper presents data on how the hospitals came together and the impact of PODS on the patient and provider experience across these hospitals and discusses it implications.


Subject(s)
Patient Care Planning/organization & administration , Patient Discharge , Patients/psychology , Caregivers , Hospitals , Humans , Medical Staff, Hospital , Nursing Staff, Hospital , Ontario , Pilot Projects
13.
Seizure ; 32: 52-61, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26552564

ABSTRACT

PURPOSE: This study investigates the performance of a cardiac-based seizure detection algorithm (CBSDA) that automatically triggers VNS (NCT01325623). METHODS: Thirty-one patients with drug resistant epilepsy were evaluated in an epilepsy monitoring unit (EMU) to assess algorithm performance and near-term clinical benefit. Long-term efficacy and safety were evaluated with combined open and closed-loop VNS. RESULTS: Sixty-six seizures (n=16 patients) were available from the EMU for analysis. In 37 seizures (n=14 patients) a ≥ 20% heart rate increase was found and 11 (n=5 patients) were associated with ictal tachycardia (iTC, 55% or 35 bpm heart rate increase, minimum of 100 bpm). Multiple CBSDA settings achieved a sensitivity of ≥ 80%. False positives ranged from 0.5 to 7.2/h. 27/66 seizures were stimulated within ± 2 min of seizure onset. In 10/17 of these seizures, where triggered VNS overlapped with ongoing seizure activity, seizure activity stopped during stimulation. Physician-scored seizure severity (NHS3-scale) showed significant improvement for complex partial seizures (CPS) at EMU discharge and through 12 months (p<0.05). Patient-scored seizure severity (total SSQ score) showed significant improvement at 3 and 6 months. Quality of life (total QOLIE-31-P score) showed significant improvement at 12 months. The responder rate (≥ 50% reduction in seizure frequency) at 12 months was 29.6% (n=8/27). Safety profiles were comparable to prior VNS trials. CONCLUSIONS: The investigated CBSDA has a high sensitivity and an acceptable specificity for triggering VNS. Despite the moderate effects on seizure frequency, combined open- and closed-loop VNS may provide valuable improvements in seizure severity and QOL in refractory epilepsy patients.


Subject(s)
Algorithms , Drug Resistant Epilepsy/diagnosis , Drug Resistant Epilepsy/therapy , Seizures/diagnosis , Seizures/therapy , Vagus Nerve Stimulation/methods , Adult , Aged , Drug Resistant Epilepsy/physiopathology , Electrocardiography , Electroencephalography , Female , Follow-Up Studies , Heart Rate/physiology , Humans , Male , Middle Aged , Pattern Recognition, Automated/methods , Prospective Studies , Quality of Life , Seizures/physiopathology , Sensitivity and Specificity , Severity of Illness Index , Tachycardia/physiopathology , Vagus Nerve Stimulation/adverse effects , Young Adult
14.
J Assoc Res Otolaryngol ; 13(3): 335-49, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22383091

ABSTRACT

The head bobber transgenic mouse line, produced by pronuclear integration, exhibits repetitive head tilting, circling behavior, and severe hearing loss. Transmitted as an autosomal recessive trait, the homozygote has vestibular and cochlea inner ear defects. The space between the semicircular canals is enclosed within the otic capsule creating a vacuous chamber with remnants of the semicircular canals, associated cristae, and vestibular organs. A poorly developed stria vascularis and endolymphatic duct is likely the cause for Reissner's membrane to collapse post-natally onto the organ of Corti in the cochlea. Molecular analyses identified a single integration of ~3 tandemly repeated copies of the transgene, a short duplicated segment of chromosome X and a 648 kb deletion of chromosome 7(F3). The three known genes (Gpr26, Cpxm2, and Chst15) in the deleted region are conserved in mammals and expressed in the wild-type inner ear during vestibular and cochlea development but are absent in homozygous mutant ears. We propose that genes critical for inner ear patterning and differentiation are lost at the head bobber locus and are candidate genes for human deafness and vestibular disorders.


Subject(s)
Deafness/genetics , Ear, Inner/abnormalities , Hyperkinesis/genetics , Mutagenesis, Insertional , Animals , Base Sequence , Body Patterning , Female , Male , Mice , Mice, Transgenic , Molecular Sequence Data
16.
Biochem Biophys Res Commun ; 410(1): 134-9, 2011 Jun 24.
Article in English | MEDLINE | ID: mdl-21651892

ABSTRACT

Prestin, a multipass transmembrane protein whose N- and C-termini are localized to the cytoplasm, must be trafficked to the plasma membrane to fulfill its cellular function as a molecular motor. One challenge in studying prestin sequence-function relationships within living cells is separating the effects of amino acid substitutions on prestin trafficking, plasma membrane localization and function. To develop an approach for directly assessing prestin levels at the plasma membrane, we have investigated whether fusion of prestin to a single pass transmembrane protein results in a functional fusion protein with a surface-exposed N-terminal tag that can be detected in living cells. We find that fusion of the biotin-acceptor peptide (BAP) and transmembrane domain of the platelet-derived growth factor receptor (PDGFR) to the N-terminus of prestin-GFP yields a membrane protein that can be metabolically-labeled with biotin, trafficked to the plasma membrane, and selectively detected at the plasma membrane using fluorescently-tagged streptavidin. Furthermore, we show that the addition of a surface detectable tag and a single-pass transmembrane domain to prestin does not disrupt its voltage-sensitive activity.


Subject(s)
Anion Transport Proteins/analysis , Biotinylation , Cell Membrane/chemistry , Recombinant Fusion Proteins/analysis , Amino Acid Sequence , Anion Transport Proteins/chemistry , Anion Transport Proteins/genetics , Biotin/chemistry , Biotin/metabolism , HEK293 Cells , Humans , Molecular Sequence Data , Patch-Clamp Techniques , Protein Structure, Tertiary , Receptors, Platelet-Derived Growth Factor/chemistry , Receptors, Platelet-Derived Growth Factor/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Sulfate Transporters
17.
J Biol Chem ; 285(5): 3103-13, 2010 Jan 29.
Article in English | MEDLINE | ID: mdl-19926791

ABSTRACT

The solute carrier transmembrane protein prestin (SLC26A5) drives an active electromechanical transduction process in cochlear outer hair cells that increases hearing sensitivity and frequency discrimination in mammals. A large intramembraneous charge movement, the nonlinear capacitance (NLC), is the electrical signature of prestin function. The transmembrane domain (TMD) helices and residues involved in the intramembrane charge displacement remain unknown. We have performed cysteine-scanning mutagenesis with serine or valine replacement to investigate the importance of cysteine residues to prestin structure and function. The distribution of oligomeric states and membrane abundance of prestin was also probed to investigate whether cysteine residues participate in prestin oligomerization and/or NLC. Our results reveal that 1) Cys-196 (TMD 4) and Cys-415 (TMD 10) do not tolerate serine replacement, and thus maintaining hydrophobicity at these locations is important for the mechanism of charge movement; 2) Cys-260 (TMD 6) and Cys-381 (TMD 9) tolerate serine replacement and are probably water-exposed; and 3) if disulfide bonds are present, they do not serve a functional role as measured via NLC. These novel findings are consistent with a recent structural model, which proposes that prestin contains an occluded aqueous pore, and we posit that the orientations of transmembrane domain helices 4 and 10 are essential for proper prestin function.


Subject(s)
Anion Transport Proteins/metabolism , Cysteine/genetics , Mutagenesis , Mutation , Animals , Disulfides , Electrophysiology/methods , Gerbillinae , Green Fluorescent Proteins/metabolism , Humans , Microscopy, Confocal/methods , Protein Structure, Secondary , Protein Transport , Serine/chemistry , Sulfate Transporters , Valine/chemistry
18.
Chem Biol ; 16(12): 1299-308, 2009 Dec 24.
Article in English | MEDLINE | ID: mdl-20064440

ABSTRACT

A major challenge to studying Fe-S cluster biosynthesis in higher eukaryotes is the lack of simple tools for imaging metallocluster binding to proteins. We describe the first fluorescent approach for in vivo detection of 2Fe2S clusters that is based upon the complementation of Venus fluorescent protein fragments via human glutaredoxin 2 (GRX2) coordination of a 2Fe2S cluster. We show that Escherichia coli and mammalian cells expressing Venus fragments fused to GRX2 exhibit greater fluorescence than cells expressing fragments fused to a C37A mutant that cannot coordinate a metallocluster. In addition, we find that maximal fluorescence in the cytosol of mammalian cells requires the iron-sulfur cluster assembly proteins ISCU and NFS1. These findings provide evidence that glutaredoxins can dimerize within mammalian cells through coordination of a 2Fe2S cluster as observed with purified recombinant proteins.


Subject(s)
Glutaredoxins/metabolism , Iron/chemistry , Sulfur/chemistry , Binding Sites , Cell Line , Circular Dichroism , Dimerization , Glutaredoxins/genetics , Humans , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Microscopy, Fluorescence , Mutation , RNA Interference , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism
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