Publications by authors named "Karlin A"

Background And Objectives: Since the initial description of related hemiplegic migraine (HM), the phenotypic spectrum has expanded from mild episodes in neurotypical individuals to potentially life-threatening events frequently seen in individuals with developmental and epileptic encephalopathies. However, the overall longitudinal course throughout childhood remains unknown.

Methods: We analyzed HM and seizure history from electronic medical records in individuals with -related HM, delineating frequency and severity of events in monthly increments through a standardized approach.

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Introduction: Since the initial description of related hemiplegic migraine (HM), the phenotypic spectrum has expanded from mild episodes in neurotypical individuals to potentially life-threatening events frequently seen in individuals with developmental and epileptic encephalopathies. However, the overall longitudinal course throughout childhood remains unknown.

Methods: We analyzed HM and seizure history in individuals with -related HM, delineating frequency and severity of events in monthly increments through a standardized approach.

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Dielectric loss is a crucial factor in determining the long-term endurance for security and energy loss of dielectric composites. Here, chain-like semiconductive fibers of titanium oxide, indium, and niobium-doped titanium oxide are used for enhancing the complex dielectric properties of a polymer through composite construction, which involves significant interface enhancements. The chain-like fibers significantly enhance the dielectric constant owing to the special morphology of the fillers and their interfacial polarization, especially at higher temperatures.

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In the last several decades, advances in genetic testing have transformed the diagnostic and therapeutic approach to pediatric epilepsy. However, the interpretation of these genetic tests often requires expert analysis and counseling. For this reason, as our molecular understanding of the linkages between abnormal cerebral physiology and genetics has grown, so too has the field of clinical epilepsy genetics.

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Article Synopsis
  • The study investigates how the protein Rad influences heart function during stress by affecting calcium ion influx and contraction strength.
  • It focuses on specific phosphorylation sites on Rad (Ser272 and Ser300) that modulate its interaction with voltage-gated calcium channels, which are crucial for increasing cardiac output.
  • The findings suggest that Rad's ability to detach from the membrane is essential for enhancing calcium currents during sympathetic nervous system activation, especially when the heart is responding to threats.
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Background: Cerebral sinovenous thrombosis (CSVT) is a rare form of pediatric stroke with significant morbidity. We determined cumulative incidence and predictors of acute seizures, remote seizures, and epilepsy after pediatric CSVT.

Methods: Retrospective analysis of 131 neonates and children with neuroimaging-confirmed CSVT enrolled between 2008 and 2020 from a single-center prospective consecutive cohort.

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Introduction: Febrile infection-related epilepsy syndrome (FIRES) is a severe childhood epilepsy with refractory status epilepticus after a typically mild febrile infection. The etiology of FIRES is largely unknown, and outcomes in most individuals with FIRES are poor.

Methods: Here, we reviewed the current state-of-the art genetic testing strategies in individuals with FIRES.

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Article Synopsis
  • The study investigates the heart's contractile reserve and how it is affected by β-adrenergic signaling, which traditionally increases heart rate and contractility during stress.
  • Researchers find that specific sites on the protein Rad, when modified by a process called phosphorylation, are essential for controlling calcium flow into heart cells (cardiomyocytes), impacting heart performance.
  • Mutations in Rad lead to significant decreases in heart function under stress and regular conditions, but introducing modified calcium-channel proteins can restore heart function, indicating potential for new heart treatments.
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The nicotinic acetylcholine receptor, a pentameric ligand-gated ion channel, converts the free energy of binding of the neurotransmitter acetylcholine into opening of its central pore. Here we present the first high-resolution structure of the receptor type found in muscle-endplate membrane and in the muscle-derived electric tissues of fish. The native receptor was purified from Torpedo electric tissue and functionally reconstituted in lipids optimal for cryo-electron microscopy.

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Postpartum low-molecular-weight heparin (LMWH) thromboprophylaxis is indicated for a substantial proportion of women. We assessed women's adherence to postpartum thromboprophylaxis and the factors associated with adherence. This retrospective cohort study was conducted at a university hospital during 2018.

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We report the first measurement of the neutron cross section on argon in the energy range of 100-800 MeV. The measurement was obtained with a 4.3-h exposure of the Mini-CAPTAIN detector to the WNR/LANSCE beam at LANL.

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Anal cancer is a relatively rare malignancy, and a minority of patients present with metastatic disease in the United States. The National Cancer Database (NCDB) was used to identify factors associated with metastatic disease at presentation and evaluate the role of pelvic radiotherapy in these patients. The NCDB was queried for patients with squamous cell cancer of the anus diagnosed between 2004 and 2013.

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Background: Improved insulin infusion set survival and faster insulin action are important issues for pump users and for the development of an artificial pancreas. The current recommendation is to change infusion sets every 3 days. Our objectives were to determine the effect of lipohypertrophy (LH) on infusion set survival and continuous glucose monitoring glucose levels.

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Arterial smooth muscle (SM) cells respond autonomously to changes in intravascular pressure, adjusting tension to maintain vessel diameter. The values of membrane potential (Vm) and sarcoplasmic Ca(2+) concentration (Ca(in)) within minutes of a change in pressure are the results of two opposing pathways, both of which use Ca(2+) as a signal. This works because the two Ca(2+)-signaling pathways are confined to distinct microdomains in which the Ca(2+) concentrations needed to activate key channels are transiently higher than Ca(in).

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The large-conductance, voltage- and Ca(2+)-gated K(+) (BK) channel consists of four α subunits, which form a voltage- and Ca(2+)-gated channel, and up to four modulatory β subunits. The β1 subunit is expressed in smooth muscle, where it slows BK channel kinetics and shifts the conductance-voltage (G-V) curve to the left at [Ca(2+)] > 2 µM. In addition to the six transmembrane (TM) helices, S1-S6, conserved in all voltage-dependent K(+) channels, BK α has a unique seventh TM helix, S0, which may contribute to the unusual rightward shift in the G-V curve of BK α in the absence of β1 and to a leftward shift in its presence.

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The large-conductance potassium channel (BK) α subunit contains a transmembrane (TM) helix S0 preceding the canonical TM helices S1 through S6. S0 lies between S4 and the TM2 helix of the regulatory β1 subunit. Pairs of Cys were substituted in the first helical turns in the membrane of BK α S0 and S4 and in β1 TM2.

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Large-conductance voltage- and Ca(2+)-gated K(+) channels are negative-feedback regulators of excitability in many cell types. They are complexes of α subunits and of one of four types of modulatory β subunits. These have intracellular N- and C-terminal tails and two transmembrane (TM) helices, TM1 and TM2, connected by an ∼100-residue extracellular loop.

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The I(Ks) potassium channel, critical to control of heart electrical activity, requires assembly of α (KCNQ1) and β (KCNE1) subunits. Inherited mutations in either I(Ks) channel subunit are associated with cardiac arrhythmia syndromes. Two mutations (S140G and V141M) that cause familial atrial fibrillation (AF) are located on adjacent residues in the first membrane-spanning domain of KCNQ1, S1.

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Sports-related concussions are common among pediatric and adolescent athletes, yet a scarcity of age-specific research often has meant that practitioners use guidelines developed for collegiate or adult populations. This situation is changing, as more studies are being published about this population that bears special attention because of the immaturity of the developing brain. This article describes existing knowledge about the epidemiology and etiology of concussions in youth athletes; discusses issues related to assessment, clinical management, and return to activity; examines special concerns related to the effects of concussion on the developing brain; and discusses prevention and education initiatives related to concussion in youth athletes.

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Large-conductance voltage- and calcium-activated potassium (BK) channels contain four pore-forming alpha subunits and four modulatory beta subunits. From the extents of disulfide cross-linking in channels on the cell surface between cysteine (Cys) substituted for residues in the first turns in the membrane of the S0 transmembrane (TM) helix, unique to BK alpha, and of the voltage-sensing domain TM helices S1-S4, we infer that S0 is next to S3 and S4, but not to S1 and S2. Furthermore, of the two beta1 TM helices, TM2 is next to S0, and TM1 is next to TM2.

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