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1.
J Cyst Fibros ; 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38485603

ABSTRACT

BACKGROUND: To address sexual and reproductive health (SRH) concerns among people with cystic fibrosis(PwCF), the CF Foundation created the Sexual Health, Reproduction, and Gender Research (SHARING) Working Group. This report summarizes CF community SRH research priorities and workshop discussions/future study planning. METHODS: Pre-workshop, we distributed a community prioritization survey on CF SRH research/care. During the workshop, we used results and reviewed existing research to establish research priorities and design studies to address identified knowledge gaps. RESULTS: A total of 303 respondents (85 % PwCF, 15 % caregivers) completed the survey. Highly-rated SRH topics were: 1) effects of CF modulator therapy on sex hormones; 2) effects of sex hormones on CF; 3) fertility; 4) pregnancy; and 5) SRH/mental health. Twenty-four workshop participants established the need for further research on sex hormones and CF, optimizing SRH care provision, and fertility/ART. CONCLUSION: SRH is an important and emerging area in CF and thoughtful consideration of community perspectives can ensure that future research is relevant and responsive.

2.
J Pediatr ; 268: 113931, 2024 May.
Article in English | MEDLINE | ID: mdl-38311237

ABSTRACT

OBJECTIVE: To analyze receipt of care at other locations within a single rural academic health system after loss to follow-up in a cardiology clinic. STUDY DESIGN: Patients with congenital heart defects seen in the clinic during 2018 and subsequently lost to cardiology follow-up were included in the study. We defined loss to follow-up as not being seen in the clinic for at least 6 months past the most recently recommended follow-up visit. Subsequent visits to other locations, including other subspecialty clinics, primary care clinics, the emergency department, and the hospital, were tracked through 2020. RESULTS: Of 235 patients (median age 7 years, 136/99 female/male), 96 (41%) were seen elsewhere in the health system. Of 96 patients with any follow-up, 40 were seen by a primary care provider and 46 by another specialist; 44 were seen in the emergency department and 12 more were hospitalized. Patients with medical comorbidities or Medicaid insurance and those living closer to the clinic were more likely to continue receiving care within the same health system. CONCLUSIONS: Patients with congenital heart defect are frequently lost to cardiology follow-up. Our study supports collaboration across specialties and between cardiology clinics and affiliated emergency departments to identify patients with congenital heart defect who have been lost to cardiology follow-up but remain within the health system. A combination of in-person and remote outreach to these patients may help them continue cardiology care.


Subject(s)
Heart Defects, Congenital , Lost to Follow-Up , Humans , Heart Defects, Congenital/therapy , Female , Male , Child , Child, Preschool , Adolescent , Infant , Emergency Service, Hospital/statistics & numerical data , Retrospective Studies , Follow-Up Studies , Primary Health Care/statistics & numerical data , Cardiology
3.
J Am Chem Soc ; 146(3): 1813-1818, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38207289

ABSTRACT

Retrosynthetic analysis is a framework for designing synthetic routes to complex molecules that generally prioritizes disconnections which reduce molecular complexity. However, strict adherence to this principle can overlook pathways involving highly complex intermediates that can be easily prepared through powerful bond-forming transformations. Herein, we demonstrate this tactic of generating excess complexity, followed by strategic bond-cleavage, as a highly effective approach for the 11-step total synthesis of the Daphniphyllum alkaloid daphenylline. To implement this strategy, we accessed a bicyclo[4.1.0]heptane core through a dearomative Buchner cycloaddition, which enabled construction of the seven-membered ring after C-C bond cleavage. Installation of the synthetically challenging quaternary stereocenter methyl group was achieved through a thia-Paternò-Büchi [2 + 2] photocycloaddition followed by stereospecific thietane reduction, further illustrating how building excess complexity can enable desired synthetic outcomes after strategic bond-breaking events. This strategy leveraging bond cleavage transformations should serve as a complement to traditional bond-forming, complexity-generating synthetic strategies.

4.
Pediatr Neonatol ; 2023 Oct 21.
Article in English | MEDLINE | ID: mdl-37926596

ABSTRACT

BACKGROUND: The clinical features of Multisystem Inflammatory Syndrome in Children (MIS-C) have been well documented, but there is limited data regarding the short term and longitudinal outcomes of children living in rural areas. We report the demographic and clinical features, as well as the multi-specialty follow-up of patients with MIS-C served by a large tertiary care rural health system. METHODS: Patients that met the Centers for Disease Control (CDC) case definition of MIS-C admitted between March 1, 2020, and March 31, 2021, were included in this case series. Manual chart review was used to report demographic characteristics, clinical, laboratory and radiologic features during acute hospitalization and multispecialty follow-up, and adherence to follow-up 6-10 weeks after hospital discharge. RESULTS: Twenty-one patients with MIS-C were admitted at our center during the review period. Ninety percent of the cohort required intensive care during hospitalization. Of 19 patients with measured ejection fractions, 52 % had some degree of left ventricular dysfunction on admission; nine patients had electrocardiogram changes on admission. The majority of patients had elevated inflammatory markers during hospitalization. Most patients had resolution of symptoms, improvement in inflammatory markers, and normal cardiac function at the time of discharge. Follow-up with pediatric cardiology, hematology-oncology and infectious disease was indicated for most patients at discharge. Of these, 100 % of patients kept initial follow-up appointments with pediatric cardiology and infectious disease, while 94 % kept initial follow-up appointments with pediatric hematology-oncology. CONCLUSION: Though most patients were critically ill during hospitalization, the majority had resolution of cardiac abnormalities and inflammatory markers at discharge and timely follow-up with multiple subspecialists after admission with MIS-C.

5.
J Am Chem Soc ; 145(20): 10960-10966, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37145091

ABSTRACT

Azabicyclo[2.1.1]hexanes (aza-BCHs) and bicyclo[1.1.1]pentanes (BCPs) have emerged as attractive classes of sp3-rich cores for replacing flat, aromatic groups with metabolically resistant, three-dimensional frameworks in drug scaffolds. Strategies to directly convert, or "scaffold hop", between these bioisosteric subclasses through single-atom skeletal editing would enable efficient interpolation within this valuable chemical space. Herein, we describe a strategy to "scaffold hop" between aza-BCH and BCP cores through a nitrogen-deleting skeletal edit. Photochemical [2+2] cycloadditions, used to prepare multifunctionalized aza-BCH frameworks, are coupled with a subsequent deamination step to afford bridge-functionalized BCPs, for which few synthetic solutions currently exist. The modular sequence provides access to various privileged bridged bicycles of pharmaceutical relevance.

6.
Opt Express ; 29(18): 28704-28724, 2021 Aug 30.
Article in English | MEDLINE | ID: mdl-34614995

ABSTRACT

We demonstrate calibration and operation of a Mueller matrix imaging microscope using dual continuously rotating anisotropic mirrors for polarization state generation and analysis. The mirrors contain highly spatially coherent nanostructure slanted columnar titanium thin films deposited onto optically thick titanium layers on quartz substrates. The first mirror acts as polarization state image generator and the second mirror acts as polarization state image detector. The instrument is calibrated using samples consisting of laterally homogeneous properties such as straight-through-air, a clear aperture linear polarizer, and a clear aperture linear retarder waveplate. Mueller matrix images are determined for spatially varying anisotropic samples consisting of a commercially available (Thorlabs) birefringent resolution target and a spatially patterned titanium slanted columnar thin film deposited onto a glass substrate. Calibration and operation are demonstrated at a single wavelength (530 nm) only, while, in principle, the instrument can operate regardless of wavelength. We refer to this imaging ellipsometry configuration as rotating-anisotropic-mirror-sample-rotating-anisotropic-mirror ellipsometry (RAM-S-RAM-E).

7.
Noncoding RNA ; 6(4)2020 Dec 16.
Article in English | MEDLINE | ID: mdl-33339309

ABSTRACT

Long non-coding RNAs (lncRNAs) are a rapidly expanding field of research, with many new transcripts identified each year. However, only a small subset of lncRNAs has been characterized functionally thus far. To aid investigating the mechanisms of action by which new lncRNAs act, bioinformatic tools and databases are invaluable. Here, we review a selection of computational tools and databases for the in silico analysis of lncRNAs, including tissue-specific expression, protein coding potential, subcellular localization, structural conformation, and interaction partners. The assembled lncRNA toolkit is aimed primarily at experimental researchers as a useful starting point to guide wet-lab experiments, mainly containing multi-functional, user-friendly interfaces. With more and more new lncRNA analysis tools available, it will be essential to provide continuous updates and maintain the availability of key software in the future.

8.
ACS Cent Sci ; 6(7): 1017-1030, 2020 Jul 22.
Article in English | MEDLINE | ID: mdl-32719821

ABSTRACT

The SARS-CoV-2 pandemic has prompted scientists from many disciplines to work collaboratively toward an effective response. As academic synthetic chemists, we examine how best to contribute to this ongoing effort.

9.
Opt Lett ; 45(13): 3541-3544, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32630893

ABSTRACT

We demonstrate calibration and operation of a single wavelength (660 nm) Mueller matrix ellipsometer in normal transmission configuration using dual continuously rotating anisotropic mirrors. The mirrors contain highly spatially coherent nanostructure slanted columnar titanium thin films deposited onto optically thick gold layers on glass substrates. Upon rotation around the mirror normal axis, sufficient modulation of the Stokes parameters of light reflected at oblique angle of incidence is achieved. Thereby, the mirrors can be used as a polarization state generator and polarization state analyzer in a generalized ellipsometry instrument. A Fourier expansion approach is found sufficient to render and calibrate the effects of the mirror rotations onto the polarized light train within the ellipsometer. The Mueller matrix elements of a set of anisotropic samples consisting of a linear polarizer and a linear retarder are measured and compared with model data, and very good agreement is observed.

10.
Org Lett ; 22(14): 5594-5599, 2020 07 17.
Article in English | MEDLINE | ID: mdl-32628491

ABSTRACT

The natural nucleoside (+)-sinefungin, structurally similar to cofactor S-adenosyl-l-methionine, inhibits various SAM-dependent methyltransferases (MTs). Access to sinefungin analogues could serve as the basis for the rational design of small molecule methyltransferase inhibitors. We developed a route to the unnatural C9' epimer of sinefungin that employed a diastereoselective Overman rearrangement to install the key C6' amino stereocenter. The ability for late-stage modification is highlighted, opening an avenue for the discovery of new MT inhibitors.

11.
J Med Chem ; 62(21): 9837-9873, 2019 11 14.
Article in English | MEDLINE | ID: mdl-31589440

ABSTRACT

Nicotinamide N-methyltransferase (NNMT) is a metabolic enzyme that methylates nicotinamide (NAM) using cofactor S-adenosylmethionine (SAM). NNMT overexpression has been linked to diabetes, obesity, and various cancers. In this work, structure-based rational design led to the development of potent and selective alkynyl bisubstrate inhibitors of NNMT. The reported nicotinamide-SAM conjugate (named NS1) features an alkyne as a key design element that closely mimics the linear, 180° transition state geometry found in the NNMT-catalyzed SAM → NAM methyl transfer reaction. NS1 was synthesized in 14 steps and found to be a high-affinity, subnanomolar NNMT inhibitor. An X-ray cocrystal structure and SAR study revealed the ability of an alkynyl linker to span the methyl transfer tunnel of NNMT with ideal shape complementarity. The compounds reported in this work represent the most potent and selective NNMT inhibitors reported to date. The rational design principle described herein could potentially be extended to other methyltransferase enzymes.


Subject(s)
Alkynes/chemistry , Alkynes/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Nicotinamide N-Methyltransferase/antagonists & inhibitors , Nicotinamide N-Methyltransferase/metabolism , Alkanes/chemistry , Alkynes/metabolism , Enzyme Inhibitors/metabolism , Enzyme Stability , Humans , K562 Cells , Molecular Docking Simulation , Nicotinamide N-Methyltransferase/chemistry , Protein Binding , Protein Conformation , Structure-Activity Relationship , Temperature
12.
J Mol Biol ; 431(5): 939-955, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30664872

ABSTRACT

The 26S proteasome is a highly complex 2.5-MDa molecular machine responsible for regulated protein degradation. Proteasome substrates are typically marked by ubiquitination for recognition at receptor sites contributed by Rpn1/S2/PSMD2, Rpn10/S5a, and Rpn13/Adrm1. Each receptor site can bind substrates directly by engaging conjugated ubiquitin chains or indirectly by binding to shuttle factors Rad23/HR23, Dsk2/PLIC/UBQLN, or Ddi1, which contain a ubiquitin-like domain (UBL) that adopts the ubiquitin fold. Previous structural studies have defined how each of the proteasome receptor sites binds to ubiquitin chains as well as some of the interactions that occur with the shuttle factors. Here, we define how hRpn10 binds to the UBQLN2 UBL domain, solving the structure of this complex by NMR, and determine affinities for each UIM region by a titration experiment. UBQLN2 UBL exhibits 25-fold stronger affinity for the N-terminal UIM-1 over UIM-2 of hRpn10. Moreover, we discover that UBQLN2 UBL is fine-tuned for the hRpn10 UIM-1 site over the UIM-2 site by taking advantage of the additional contacts made available through the longer UIM-1 helix. We also test hRpn10 versatility for the various ubiquitin chains to find less specificity for any particular linkage type compared to hRpn1 and hRpn13, as expected from the flexible linker region that connects the two UIMs; nonetheless, hRpn10 does exhibit some preference for K48 and K11 linkages. Altogether, these results provide new insights into the highly complex and complementary roles of the proteasome receptor sites and shuttle factors.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Autophagy-Related Proteins/metabolism , Proteasome Endopeptidase Complex/metabolism , RNA-Binding Proteins/metabolism , Binding Sites/physiology , DNA-Binding Proteins/metabolism , HCT116 Cells , Humans , Protein Binding/physiology , Ubiquitins/metabolism
13.
J Org Chem ; 84(8): 4670-4679, 2019 04 19.
Article in English | MEDLINE | ID: mdl-30412410

ABSTRACT

α-Arylations of cyclopropyl and related nitriles provide access to important synthetic intermediates and pharmacophores for biologically active molecules. However, robust methods for coupling of sterically encumbered partners have remained elusive. Through optimization using high-throughput experimentation (HTE), the NiXantphos ligand was found to be effective in the coupling of sterically hindered ß-substituted cyclopropyl nitriles with a number of aryl groups and heterocycles, including those containing acidic N-H and O-H bonds.


Subject(s)
Cyclopropanes/chemistry , Hydrocarbons, Halogenated/chemistry , Nitriles/chemistry , Palladium/chemistry , Catalysis , Ligands , Molecular Structure
14.
Nat Neurosci ; 21(7): 963-973, 2018 07.
Article in English | MEDLINE | ID: mdl-29915192

ABSTRACT

The paraventricular nucleus of the thalamus (PVT) is increasingly being recognized as a critical node linking stress detection to the emergence of adaptive behavioral responses to stress. However, despite growing evidence implicating the PVT in stress processing, the neural mechanisms by which stress impacts PVT neurocircuitry and promotes stressed states remain unknown. Here we show that stress exposure drives a rapid and persistent reduction of inhibitory transmission onto projection neurons of the posterior PVT (pPVT). This stress-induced disinhibition of the pPVT was associated with a locus coeruleus-mediated rise in the extracellular concentration of dopamine in the midline thalamus, required the function of dopamine D2 receptors on PVT neurons, and increased sensitivity to stress. Our findings define the locus coeruleus as an important modulator of PVT function: by controlling the inhibitory tone of the pPVT, it modulates the excitability of pPVT projection neurons and controls stress responsivity.


Subject(s)
Dopamine/metabolism , Locus Coeruleus/metabolism , Neural Inhibition/physiology , Neurons/metabolism , Receptors, Dopamine D2/metabolism , Stress, Physiological/physiology , Thalamus/metabolism , Animals , Electroshock , Fear/physiology , Female , Membrane Glycoproteins , Mice , Neural Pathways , Receptors, Interleukin-1
15.
PLoS Negl Trop Dis ; 11(3): e0005467, 2017 03.
Article in English | MEDLINE | ID: mdl-28319196

ABSTRACT

The human blood fluke Schistosoma mansoni causes intestinal schistosomiasis, a widespread neglected tropical disease. Infection of freshwater snails Biomphalaria spp. is an essential step in the transmission of S. mansoni to humans, although the physiological interactions between the parasite and its obligate snail host that determine success or failure are still poorly understood. In the present study, the B. glabrata embryonic (Bge) cell line, a widely used in vitro model for hemocyte-like activity, was used to investigate membrane properties, and assess the impact of larval transformation proteins (LTP) on identified ion channels. Whole-cell patch clamp recordings from Bge cells demonstrated that a Zn2+-sensitive H+ channel serves as the dominant plasma membrane conductance. Moreover, treatment of Bge cells with Zn2+ significantly inhibited an otherwise robust production of reactive oxygen species (ROS), thus implicating H+ channels in the regulation of this immune function. A heat-sensitive component of LTP appears to target H+ channels, enhancing Bge cell H+ current over 2-fold. Both Bge cells and B. glabrata hemocytes express mRNA encoding a hydrogen voltage-gated channel 1 (HVCN1)-like protein, although its function in hemocytes remains to be determined. This study is the first to identify and characterize an H+ channel in non-neuronal cells of freshwater molluscs. Importantly, the involvement of these channels in ROS production and their modulation by LTP suggest that these channels may function in immune defense responses against larval S. mansoni.


Subject(s)
Biomphalaria/embryology , Biomphalaria/enzymology , Cell Membrane/enzymology , Proton Pumps/metabolism , Animals , Cells, Cultured , Patch-Clamp Techniques , Reactive Oxygen Species/metabolism
16.
Adv Exp Med Biol ; 859: 197-211, 2015.
Article in English | MEDLINE | ID: mdl-26238054

ABSTRACT

Synaptic plasticity has the capacity to alter the function of neural circuits, and long-term potentiation (LTP) of synaptic transmission induced by high frequency electrical activity has the capacity to store information in neural circuits. The cellular and molecular mechanisms of LTP have been studied intensively for many years and much progress has been made on this front. By contrast, how synaptic plasticity alters circuit function has received much less attention and remains poorly understood. Voltage imaging provides a powerful general technique for the study of neural circuitry, and studies of synaptic plasticity with voltage imaging are beginning to reveal important aspects of how the function of a neural circuit can change when the strength of its synapses has been modified. The hippocampus has an important role in learning and memory and the plasticity of its synapses has received much attention. Voltage imaging with voltage sensitive dye in the CA1 region of a hippocampal slice has shown that spatial patterns of enhancement following LTP induction can diverge from the spatial patterns elicited by electrical stimulation, suggesting that LTP exhibits a distinct organizational structure. LTP can alter the throughput of electrical activity in the dentate gyrus of a hippocampal slice, to gate transmission on to the CA3 region. The spatial patterns evoked by complex electrical stimulation can be stored within the CA3 region in a hippocampal slice, allowing patterns to be reconstructed with simpler electrical stimulation. Thus, voltage imaging has demonstrated that the CA3 circuit has the capacity for pattern completion. These studies with voltage sensitive dye illustrate a range of interesting and novel questions that can be addressed at the population level. It is hoped that future imaging experiments with single-cell resolution using genetically-encoded voltage sensors will provide a more detailed picture of how synaptic plasticity modifies the information processing capabilities of neural circuits.


Subject(s)
CA1 Region, Hippocampal/physiology , CA3 Region, Hippocampal/physiology , Dentate Gyrus/physiology , Fluorescent Dyes/chemistry , Long-Term Potentiation/physiology , Neurons/physiology , Voltage-Sensitive Dye Imaging/methods , Animals , CA1 Region, Hippocampal/ultrastructure , CA3 Region, Hippocampal/ultrastructure , Deep Brain Stimulation , Dentate Gyrus/ultrastructure , Membrane Potentials/physiology , Microtomy , Nerve Net/physiology , Nerve Net/ultrastructure , Neurons/ultrastructure , Rats , Spatio-Temporal Analysis , Synapses/physiology , Synapses/ultrastructure , Synaptic Transmission , Voltage-Sensitive Dye Imaging/instrumentation
17.
J Neurosci ; 34(29): 9743-53, 2014 Jul 16.
Article in English | MEDLINE | ID: mdl-25031412

ABSTRACT

The dentate gyrus serves as a gateway to the hippocampus, filtering and processing sensory inputs as an animal explores its environment. The hilus occupies a strategic position within the dentate gyrus from which it can play a pivotal role in these functions. Inputs from dentate granule cells converge on the hilus, and excitatory hilar mossy cells redistribute these signals back to granule cells to transform a pattern of cortical input into a new pattern of output to the hippocampal CA3 region. Using voltage-sensitive dye to image electrical activity in rat hippocampal slices, we explored how long-term potentiation (LTP) of different excitatory synapses modifies the flow of information. Theta burst stimulation of the perforant path potentiated responses throughout the molecular layer, but left responses in the CA3 region unchanged. By contrast, theta burst stimulation of the granule cell layer potentiated responses throughout the molecular layer, as well as in the CA3 region. Theta burst stimulation of the granule cell layer potentiated CA3 responses not only to granule cell layer stimulation but also to perforant path stimulation. Potentiation of responses in the CA3 region reflected NMDA receptor-dependent LTP of upstream synapses between granule cells and mossy cells, with no detectable contribution from NMDA receptor-independent LTP of local CA3 mossy fiber synapses. Potentiation of transmission to the CA3 region required LTP in both granule cell→mossy cell and mossy cell→granule cell synapses. This bidirectional plasticity enables hilar circuitry to regulate the flow of information through the dentate gyrus and on to the hippocampus.


Subject(s)
Dentate Gyrus/cytology , Dentate Gyrus/physiology , Long-Term Potentiation/physiology , Nerve Net/physiology , Neurons/physiology , Analysis of Variance , Animals , Biophysics , Electric Stimulation , Excitatory Amino Acid Antagonists/pharmacology , GABA Antagonists/pharmacology , In Vitro Techniques , Long-Term Potentiation/drug effects , Male , Nerve Net/drug effects , Neurons/drug effects , Pyridazines/pharmacology , Rats , Rats, Sprague-Dawley , Valine/analogs & derivatives , Valine/pharmacology , Voltage-Sensitive Dye Imaging
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