Atopic dermatitis (eczema) guidelines: 2023 American Academy of Allergy, Asthma and Immunology/American College of Allergy, Asthma and Immunology Joint Task Force on Practice Parameters GRADE- and Institute of Medicine-based recommendations.

BACKGROUND: Guidance addressing atopic dermatitis (AD) management, last issued in 2012 by the American Academy of Allergy, Asthma and Immunology/American College of Allergy, Asthma and Immunology Joint Task Force, requires updating as a result of new treatments and improved guideline and evidence synthesis methodology. OBJECTIVE: To produce evidence-based guidelines that support patients, clinicians, and other decision-makers in the optimal treatment of AD. METHODS: A multidisciplinary guideline panel consisting of patients and caregivers, AD experts (dermatology and allergy/immunology), primary care practitioners (family medicine, pediatrics, internal medicine), and allied health professionals (psychology, pharmacy, nursing) convened, prioritized equity, diversity, and inclusiveness, and implemented management strategies to minimize influence of conflicts of interest. The Evidence in Allergy Group supported guideline development by performing systematic evidence reviews, facilitating guideline processes, and holding focus groups with patient and family partners. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach informed rating the certainty of evidence and strength of recommendations. Evidence-to-decision frameworks, subjected to public comment, translated evidence to recommendations using trustworthy guideline principles. RESULTS: The panel agreed on 25 recommendations to gain and maintain control of AD for patients with mild, moderate, and severe AD. The eAppendix provides practical information and implementation considerations in 1-2 page patient-friendly handouts. CONCLUSION: These evidence-based recommendations address optimal use of (1) topical treatments (barrier moisturization devices, corticosteroids, calcineurin inhibitors, PDE4 inhibitors [crisaborole], topical JAK inhibitors, occlusive [wet wrap] therapy, adjunctive antimicrobials, application frequency, maintenance therapy), (2) dilute bleach baths, (3) dietary avoidance/elimination, (4) allergen immunotherapy, and (5) systemic treatments (biologics/monoclonal antibodies, small molecule immunosuppressants [cyclosporine, methotrexate, azathioprine, mycophenolate, JAK inhibitors], and systemic corticosteroids) and UV phototherapy (light therapy).

Allergen immunotherapy for atopic dermatitis: Systematic review and meta-analysis of benefits and harms.

BACKGROUND: Atopic dermatitis (AD, eczema) is driven by a combination of skin barrier defects, immune dysregulation, and extrinsic stimuli such as allergens, irritants, and microbes. The role of environmental allergens (aeroallergens) in triggering AD remains unclear. OBJECTIVE: We systematically synthesized evidence regarding the benefits and harms of allergen immunotherapy (AIT) for AD. METHODS: As part of the 2022 American Academy of Allergy, Asthma & Immunology/American College of Allergy, Asthma and Immunology Joint Task Force on Practice Parameters AD Guideline update, we searched the MEDLINE, EMBASE, CENTRAL, CINAHL, LILACS, Global Resource for Eczema Trials, and Web of Science databases from inception to December 2021 for randomized controlled trials comparing subcutaneous immunotherapy (SCIT), sublingual immunotherapy (SLIT), and/or no AIT (placebo or standard care) for guideline panel-defined patient-important outcomes: AD severity, itch, AD-related quality of life (QoL), flares, and adverse events. Raters independently screened, extracted data, and assessed risk of bias in duplicate. We synthesized intervention effects using frequentist and Bayesian random-effects models. The GRADE approach determined the quality of evidence. RESULTS: Twenty-three randomized controlled trials including 1957 adult and pediatric patients sensitized primarily to house dust mite showed that add-on SCIT and SLIT have similar relative and absolute effects and likely result in important improvements in AD severity, defined as a 50% reduction in SCORing Atopic Dermatitis (risk ratio [95% confidence interval] 1.53 [1.31-1.78]; 26% vs 40%, absolute difference 14%) and QoL, defined as an improvement in Dermatology Life Quality Index by 4 points or more (risk ratio [95% confidence interval] 1.44 [1.03-2.01]; 39% vs 56%, absolute difference 17%; both outcomes moderate certainty). Both routes of AIT increased adverse events (risk ratio [95% confidence interval] 1.61 [1.44-1.79]; 66% with SCIT vs 41% with placebo; 13% with SLIT vs 8% with placebo; high certainty). AIT's effect on sleep disturbance and eczema flares was very uncertain. Subgroup and sensitivity analyses were consistent with the main findings. CONCLUSIONS: SCIT and SLIT to aeroallergens, particularly house dust mite, can similarly and importantly improve AD severity and QoL. SCIT increases adverse effects more than SLIT. These findings support a multidisciplinary and shared decision-making approach to optimally managing AD.

Systemic treatments for atopic dermatitis (eczema): Systematic review and network meta-analysis of randomized trials.

BACKGROUND: Atopic dermatitis (AD) is an inflammatory skin condition with multiple systemic treatments and uncertainty regarding their comparative impact on AD outcomes. OBJECTIVE: We sought to systematically synthesize the benefits and harms of AD systemic treatments. METHODS: For the 2023 American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, Web of Science, and GREAT databases from inception to November 29, 2022, for randomized trials addressing systemic treatments and phototherapy for AD. Paired reviewers independently screened records, extracted data, and assessed risk of bias. Random-effects network meta-analyses addressed AD severity, itch, sleep, AD-related quality of life, flares, and harms. The Grading of Recommendations Assessment, Development and Evaluation approach informed certainty of evidence ratings. This review is registered in the Open Science Framework (https://osf.io/e5sna). RESULTS: The 149 included trials (28,686 patients with moderate-to-severe AD) evaluated 75 interventions. With high-certainty evidence, high-dose upadacitinib was among the most effective for 5 of 6 patient-important outcomes; high-dose abrocitinib and low-dose upadacitinib were among the most effective for 2 outcomes. These Janus kinase inhibitors were among the most harmful in increasing adverse events. With high-certainty evidence, dupilumab, lebrikizumab, and tralokinumab were of intermediate effectiveness and among the safest, modestly increasing conjunctivitis. Low-dose baricitinib was among the least effective. Efficacy and safety of azathioprine, oral corticosteroids, cyclosporine, methotrexate, mycophenolate, phototherapy, and many novel agents are less certain. CONCLUSIONS: Among individuals with moderate-to-severe AD, high-certainty evidence demonstrates that high-dose upadacitinib is among the most effective in addressing multiple patient-important outcomes, but also is among the most harmful. High-dose abrocitinib and low-dose upadacitinib are effective, but also among the most harmful. Dupilumab, lebrikizumab, and tralokinumab are of intermediate effectiveness and have favorable safety.

Drug-Drug Interactions of Glecaprevir and Pibrentasvir Coadministered With Human Immunodeficiency Virus Antiretrovirals.

BACKGROUND: Treatment of patients coinfected with hepatitis C and human immunodeficiency viruses (HCV; HIV) requires careful consideration of potential drug-drug interactions between HCV direct-acting antiviral agents (DAA) and HIV antiretrovirals. Glecaprevir/pibrentasvir is a fixed-dose combination of an NS3/4A protease inhibitor and an NS5A inhibitor approved for the treatment of chronic HCV genotype 1-6 infection, including patients with HIV coinfection. METHODS: A series of phase 1 studies was conducted to evaluate potential interactions of glecaprevir and pibrentasvir with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide, abacavir/dolutegravir/lamivudine, raltegravir, rilpivirine, atazanavir/ritonavir, darunavir/ritonavir, lopinavir/ritonavir, or efavirenz/emtricitabine/tenofovir disoproxil fumarate. Pharmacokinetics of the antiretrovirals and DAAs were characterized when administered alone and in combination to quantify changes in systemic drug exposure. RESULTS: Glecaprevir area under the curve increased >4-fold in the presence of ritonavir-boosted HIV protease inhibitors, while pibrentasvir concentrations were not significantly affected; elevations in alanine transaminase occurred in combination with atazanavir/ritonavir only. Exposures of glecaprevir and pibrentasvir may be significantly decreased by efavirenz. Coadministration with glecaprevir and pibrentasvir did not result in clinically significant changes in the exposure of any antiretroviral agents. CONCLUSIONS: Atazanavir is contraindicated with glecaprevir/pibrentasvir and use of boosted protease inhibitors or efavirenz is not recommended. No clinically significant interactions were observed with other studied antiretrovirals.

Translation of In Vitro Transport Inhibition Studies to Clinical Drug-Drug Interactions for Glecaprevir and Pibrentasvir.

Glecaprevir and pibrentasvir are oral direct-acting antiviral agents approved in combination for treatment of chronic hepatitis C viral infection. In vitro studies identified the combination as potentially clinically relevant inhibitors of the efflux transporters P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and the hepatic uptake transporters organic anion transporting polypeptide (OATP) 1B1 and OATP1B3. Glecaprevir inhibited P-gp, BCRP, OATP1B1, and OATP1B3 with IC50 values of 0.33, 2.3, 0.017, and 0.064 µM, respectively. Pibrentasvir inhibited P-gp, BCRP, and OATP1B1 with IC50 values of 0.036, 14, and 1.3 µM, respectively. Neither agent inhibited organic cation transporter (OCT) 1, OCT2, organic anion transporter (OAT) 1, OAT3, multidrug and toxin extrusion (MATE) 1, or MATE2K. Open-label phase 1 clinical drug-drug interaction studies were conducted in healthy subjects to evaluate interaction potential of glecaprevir/pibrentasvir and coadministered selective substrates for P-gp (digoxin, dabigatran etexilate, and sofosbuvir), BCRP (rosuvastatin and sofosbuvir), and OATP1B1/3 (pravastatin and rosuvastatin). The pharmacokinetic maximum plasma concentration (C max) and area under the concentration-time curve (AUC) parameters were evaluated for probe substrates alone and in combination with glecaprevir/pibrentasvir. The C max central values increased by 72%, 105%, 123%, 462%, and 66% for digoxin, dabigatran, pravastatin, rosuvastatin, and sofosbuvir, respectively, and the AUC central values increased by 48%, 138%, 130%, 115%, and 125% for digoxin, dabigatran, pravastatin, rosuvastatin, and sofosbuvir, respectively. Exposure of sofosbuvir metabolite GS-331007 (nucleoside analog) was similar with or without glecaprevir/pibrentasvir. The outcomes of the clinical drug-drug interaction studies confirmed clinically relevant inhibition of P-gp, BCRP, and OATP1B1/3, and were used to provide dosing guidance for the concomitant use of glecaprevir/pibrentasvir with relevant transporter substrates.

Values and Preferences of Patients and Caregivers Regarding Treatment of Atopic Dermatitis (Eczema): A Systematic Review.

Importance: Patient values and preferences can inform atopic dermatitis (AD) care. Systematic summaries of evidence addressing patient values and preferences have not previously been available. Objective: To inform American Academy of Allergy, Asthma & Immunology (AAAAI)/American College of Allergy, Asthma and Immunology (ACAAI) Joint Task Force on Practice Parameters AD guideline development, patient and caregiver values and preferences in the management of AD were systematically synthesized. Evidence Review: Paired reviewers independently screened MEDLINE, Embase, PsycINFO, and CINAHL databases from inception until March 20, 2022, for studies of patients with AD or their caregivers, eliciting values and preferences about treatment, rated risk of bias, and extracted data. Thematic and inductive content analysis to qualitatively synthesize the findings was used. Patients, caregivers, and clinical experts provided triangulation. The GRADE-CERQual (Grading of Recommendations Assessment, Development and Evaluation-Confidence in the Evidence from Reviews of Qualitative Research) informed rating of the quality of evidence. Findings: A total of 7780 studies were identified, of which 62 proved eligible (n = 19 442; median age across studies [range], 15 years [3-44]; 59% female participants). High certainty evidence showed that patients and caregivers preferred to start with nonmedical treatments and to step up therapy with increasing AD severity. Moderate certainty evidence showed that adverse effects from treatment were a substantial concern. Low certainty evidence showed that patients and caregivers preferred odorless treatments that are not visible and have a minimal effect on daily life. Patients valued treatments capable of relieving itching and burning skin and preferred to apply topical corticosteroids sparingly. Patients valued a strong patient-clinician relationship. Some studies presented varied perspectives and 18 were at high risk for industry sponsorship bias. Conclusions and Relevance: In the first systematic review to address patient values and preferences in management of AD to our knowledge, 6 key themes that may inform optimal clinical care, practice guidelines, and future research have been identified.

Treslin, DUE-B, and GEMC1 cannot complement Sld3 mutants in fission yeast.

Initiation of DNA replication in eukaryotes is an evolutionarily conserved process that involves two distinct steps: the formation of prereplication complexes at replication origins in G1 and the assembly of preinitiation complexes (pre-ICs) in S phase, which leads to activation of the replication helicase. For the assembly of pre-ICs in yeast, formation of the Sld2-Dpb11-Sld3 complex is a critical event that requires phosphorylation of Sld2 and Sld3 by cyclin-dependent kinase. In mammals, RecQL4 and TopBP1 are excellent ortholog candidates for Sld2 and Dpb11, respectively. In this past year, three TopBP1-interacting proteins Treslin/Ticrr, GEMC1, and DUE-B have been identified in metazoans as possible functional orthologs of the yeast Sld3. To test this hypothesis, we carried out several complementation tests in fission yeast. The proteins were expressed at various levels in the temperature-sensitive sld3-10 mutant and in cells that lack endogenous Sld3. Our result showed that none of these metazoan proteins could rescue growth defect of the sld3 mutants. Although the result may have several interpretations, it is possible that the helicase activation in mammals has diverged in complexity during evolution from that in yeasts and may involve multiple players that interact with TopBP1.

Effects of elagolix on the pharmacokinetics of omeprazole and its metabolites in healthy premenopausal women.

This study evaluated the effect of repeated doses of elagolix on the pharmacokinetics (PK) of omeprazole and its metabolites in healthy premenopausal female subjects. Adult premenopausal female subjects (N = 20) received a single oral dose of omeprazole (40 mg) on day 1 and day 11 and oral doses of elagolix (300 mg) twice-daily on days 3-11. Serial blood samples for assay of omeprazole and its metabolites were collected for 24 h after dosing on days 1 and 11. PK parameters were calculated for omeprazole, 5-hydroxyomeprazole and omeprazole sulfone; and were compared between day 1 and day 11. Pharmacogenetic testing was performed for CYP2C19 variant alleles and the results were used to compare the magnitude of elagolix-omeprazole drug-drug interaction (DDI) between the different genotype subgroups. Administration of elagolix 300 mg twice-daily for 9 days increased omeprazole exposure by 1.8-fold and decreased the metabolite-to-parent ratio for 5-hydroxyomeprazole by ~60%. Conversely, there was an increase in the metabolite-to-parent ratio for omeprazole sulfone by 25%. Elagolix increased omeprazole exposures by 2- to 2.5-fold in CYP2C19 extensive (EM) and intermediate (IM) metabolizer subjects, but decreased omeprazole exposures by 40% in poor metabolizer subjects. Exposures of 5-hydroxyomeprazole decreased by 20%-30% in all genotype subgroups, and omeprazole sulfone exposures increased by ~3-fold in EM and IM subjects. Elagolix is a weak inhibitor of CYP2C19 and exposure of CYP2C19 substrates may be increased upon coadministration with elagolix. Omeprazole may exhibit drug interactions due to multiple mechanisms other than CYP2C19-mediated metabolism; complicating the interpretation of results from omeprazole DDI studies.

Effect of Upadacitinib on the Pharmacokinetics of Rosuvastatin or Atorvastatin in Healthy Subjects.

This phase 1, 2-part, 2-period, open-label, drug-drug interaction study evaluated the potential for pharmacokinetic interactions between upadacitinib and rosuvastatin, an organic anion transporting polypeptide (OATP) 1B1 and breast cancer resistance protein substrate, or atorvastatin, a cytochrome P450 3A, OATP1B1, and OATP1B3 substrate, in 36 healthy volunteers. During period 1, a single dose of rosuvastatin (5 mg; part 1) or atorvastatin (10 mg; part 2) was administered on day 1, followed by a washout period of 5 days. During period 2, once-daily doses of upadacitinib extended-release (30 mg) were administered on days 1 to 10, and a single dose of rosuvastatin (5 mg; part 1) or atorvastatin (10 mg; part 2) was administered 1 hour after the upadacitinib dose on day 7. Serial blood samples were collected for assays of drug concentrations. In Part 1, rosuvastatin maximum observed plasma concentration (Cmax ) and area under the plasma concentration-time curve from time 0 to infinity (AUCinf ) were 23% and 33% lower, respectively, when administered with upadacitinib relative to when administered alone. In part 2, atorvastatin Cmax and AUCinf was 11% and 23% lower, respectively, when administered with upadacitinib relative to when administered alone. The Cmax and AUCinf of the active metabolite ortho-hydroxyatorvastatin remained unchanged. Administration of a single 5-mg dose of rosuvastatin or a single 10-mg dose of atorvastatin had no relevant effect on upadacitinib Cmax or area under the plasma concentration-time curve. These results demonstrated that upadacitinib has no clinically relevant effect on the pharmacokinetics of rosuvastatin and atorvastatin or on substrates transported by OATP1B or breast cancer resistance protein.

NaV1.2 EFL domain allosterically enhances Ca2+ binding to sites I and II of WT and pathogenic calmodulin mutants bound to the channel CTD.

Neuronal voltage-gated sodium channel NaV1.2 C-terminal domain (CTD) binds calmodulin (CaM) constitutively at its IQ motif. A solution structure (6BUT) and other NMR evidence showed that the CaM N domain (CaMN) is structurally independent of the C-domain (CaMC) whether CaM is bound to the NaV1.2IQp (1,901-1,927) or NaV1.2CTD (1,777-1,937) with or without calcium. However, in the CaM + NaV1.2CTD complex, the Ca2+ affinity of CaMN was more favorable than in free CaM, while Ca2+ affinity for CaMC was weaker than in the CaM + NaV1.2IQp complex. The CTD EF-like (EFL) domain allosterically widened the energetic gap between CaM domains. Cardiomyopathy-associated CaM mutants (N53I(N54I), D95V(D96V), A102V(A103V), E104A(E105A), D129G(D130G), and F141L(F142L)) all bound the NaV1.2 IQ motif favorably under resting (apo) conditions and bound calcium normally at CaMN sites. However, only N53I and A102V bound calcium at CaMC sites at [Ca2+] < 100 µM. Thus, they are expected to respond like wild-type CaM to Ca2+ spikes in excitable cells.

High-frequency microstimulation in human globus pallidus and substantia nigra.

Deep brain stimulation of the basal ganglia and other brain regions has been used successfully to treat a variety of neurological disorders. However, the mechanisms by which it works, remain unclear. In a previous study, we showed that locally delivered single current pulses delivered from a nearby microelectrode are sufficient to inhibit firing in the internal globus pallidus for tens of milliseconds. The GPi and the substantia nigra pars reticulata are the output nuclei of the basal ganglia and share many anatomical and physiological features. The goal of the current study was to examine the after-effects of trains of high-frequency microstimulation on neuronal firing in the GPi of Parkinson's disease and dystonia patients as well as in the SNr of PD patients. Microelectrode recordings and microstimulation were performed in a total of 57 patients during stereotactic surgery. We found that firing in the GPi and SNr is inhibited for several hundreds of milliseconds following the end of a short, 200 Hz high-frequency train delivered through the recording electrode (e.g., on average 618 ms when stimulating in the SNr with a 0.5 s train of 4 microA pulses at 200 Hz). Inhibition duration usually increased with increasing current intensity, train frequency and generally peaked for trains of 1-2 s, while it decreased with increasing train durations. Statistical analysis with general linear models revealed a significant linear relationship between current intensity and inhibition duration in all nuclei and patient groups. There was also a significant relationship between train frequency and inhibition duration in the SNr and GPi of PD patients and between train duration and inhibition duration in the GPi of PD patients. There was no significant difference in inhibition duration across patient groups but the current threshold for inhibition was significantly different in the SNr compared to the GPi. The characteristics of the inhibition observed are consistent with stimulation-induced GABA release following activation of the GABAergic afferents in the SNr and GPi. The findings suggest that high-frequency microstimulation of the GPi and SNr depresses local neuronal activity and synaptic transmission, and such mechanisms may contribute to the therapeutic effects of DBS.

Pathophysiology of Hyperkalemia Presenting as Brugada Pattern on Electrocardiogram (ECG).

BACKGROUND Brugada phenocopies (BrP) are clinical and electrocardiographic (ECG) entities elicited by reversible medical conditions speculated to have pathogenesis rooted in ion current imbalances or conduction delays within the myocardial wall. During an inciting pathologic condition, it produces ECG patterns identical to those of congenitally-acquired Brugada syndrome and subsequently returns to normal ECG patterns upon resolution of the medical condition. This case report describes a 26-year-old man presenting to the Emergency Department (ED) for suspected heroin overdose with a rare ECG consistent with BrP secondary to acute hyperkalemia. CASE REPORT A 26-year-old man with a history of substance abuse and a seizure disorder presented to the ED for acute encephalopathy secondary to a heroin overdose complicated by severe rhabdomyolysis and acute renal failure. Laboratory investigations showed acute hyperkalemia (potassium of 7.2 mmol/L) in addition to an elevated creatine kinase, severe transaminitis, and elevated creatinine. His ECG on admission revealed Brugada-like changes in leads V1-V2, with subsequent resolution upon bicarbonate administration and normalization of potassium. After initial stabilization, the patient was admitted to the Intensive Care Unit (ICU). His rhabdomyolysis and acute kidney injury improved after copious rehydration. He was found to have community-acquired pneumonia, with a negative infectious disease workup, that improved with antibiotics. Upon resolution of his hypoxemic respiratory failure and improvement in mentation, he was discharged from the hospital. CONCLUSIONS Our case report adds to the growing literature on BrP and highlights the importance of recognizing its characteristic ECG pattern as a unique presentation of a common electrolyte derangement.

"The Secret Life of Human Donor Hearts": An Examination of Transcriptomic Events During Cold Storage.

BACKGROUND: Ischemic tolerance of donor hearts has a major impact on the efficiency in utilization and clinical outcomes. Molecular events during storage may influence the severity of ischemic injury. METHODS: RNA sequencing was used to study the transcriptional profile of the human left ventricle (LV, n=4) and right ventricle (RV, n=4) after 0, 4, and 8 hours of cold storage in histidine-tryptophan-ketoglutarate preservation solution. Gene set enrichment analysis and gene ontology analysis was used to examine transcriptomic changes with cold storage. Terminal deoxynucleotidyl transferase 2´-Deoxyuridine, 5´-Triphosphate nick end labeling and p65 staining was used to examine for cell death and NFκB activation, respectively. RESULTS: The LV showed activation of genes related to inflammation and allograft rejection but downregulation of oxidative phosphorylation and fatty acid metabolism pathway genes. In contrast, inflammation-related genes were down-regulated in the RV and while oxidative phosphorylation genes were activated. These transcriptomic changes were most significant at the 8 hours with much lower differences observed between 0 and 4 hours. RNA velocity estimates corroborated the finding that immune-related genes were activated in the LV but not in the RV during storage. With increasing preservation duration, the LV showed an increase in nuclear translocation of NFκB (p65), whereas the RV showed increased cell death close to the endocardium especially at 8 hours. CONCLUSIONS: Our results demonstrated that the LV and RV of human donor hearts have distinct responses to cold ischemic storage. Transcriptomic changes related to inflammation, oxidative phosphorylation, and fatty acid metabolism pathways as well as cell death and NFκB activation were most pronounced after 8 hours of storage.

Salting-out assisted liquid/liquid extraction with acetonitrile: a new high throughput sample preparation technique for good laboratory practice bioanalysis using liquid chromatography-mass spectrometry.

Acetonitrile, an organic solvent miscible with aqueous phase, has seen thousands of publications in the literature as an efficient deproteinization reagent. The use of acetonitrile for liquid-liquid extraction (LLE), however, has seen very limited application due to its miscibility with aqueous phase. The interest in LLE with acetonitrile has been pursued and reported in the literature by significantly lowering the temperature of the mixture or increasing the salt concentration in the mixture of acetonitrile and aqueous phase, resulting in the separation of the acetonitrile phase from aqueous phase, as observed in conventional LLE. However, very limited application of these methods has been reported. The throughput was limited. In this report, we report a new sample preparation technique, salting-out assisted liquid-liquid extraction with acetonitrile, for high-throughput good laboratory practice sample analysis using LCMS, Two compounds from an approved drug, Kaletra, were used to demonstrate the extractability of drugs from human plasma matrix. Magnesium sulfate was used as the salting-out reagent. Extracts were diluted and then injected into a reversed phase LC-MS/MS system directly. One 96-well plate was extracted with this new approach to evaluate multiple parameters of a good laboratory practice analytical method. Results indicate that the method is rapid, reliable and suitable for regulated bioanalysis. With minimal modification, this approach has been used for high-throughput good laboratory practice analysis of a number of compounds under development at Abbott.

Calcium triggers reversal of calmodulin on nested anti-parallel sites in the IQ motif of the neuronal voltage-dependent sodium channel NaV1.2.

Several members of the voltage-gated sodium channel family are regulated by calmodulin (CaM) and ionic calcium. The neuronal voltage-gated sodium channel NaV1.2 contains binding sites for both apo (calcium-depleted) and calcium-saturated CaM. We have determined equilibrium dissociation constants for rat NaV1.2 IQ motif [IQRAYRRYLLK] binding to apo CaM (~3nM) and (Ca2+)4-CaM (~85nM), showing that apo CaM binding is favored by 30-fold. For both apo and (Ca2+)4-CaM, NMR demonstrated that NaV1.2 IQ motif peptide (NaV1.2IQp) exclusively made contacts with C-domain residues of CaM (CaMC). To understand how calcium triggers conformational change at the CaM-IQ interface, we determined a solution structure (2M5E.pdb) of (Ca2+)2-CaMC bound to NaV1.2IQp. The polarity of (Ca2+)2-CaMC relative to the IQ motif was opposite to that seen in apo CaMC-Nav1.2IQp (2KXW), revealing that CaMC recognizes nested, anti-parallel sites in Nav1.2IQp. Reversal of CaM may require transient release from the IQ motif during calcium binding, and facilitate a re-orientation of CaMN allowing interactions with non-IQ NaV1.2 residues or auxiliary regulatory proteins interacting in the vicinity of the IQ motif.

Validation of the Chinese Translation of the Spatial Hearing Questionnaire and Its Short Form.

PURPOSE: Few questionnaires address how to measure spatial hearing ability in complex listening situations. The purpose of the study was (a) to validate the Chinese translation of the Spatial Hearing Questionnaire (C-SHQ) among Chinese participants and (b) to provide a shortened version for the purpose of clinical screening. METHOD: This was a cross-sectional study. The C-SHQ was developed from the process of translation and back-translation of the original 24-item, English version (Tyler, Perreau, & Ji, 2009). The C-SHQ was administered to 146 patients at the Department of Otolaryngology Clinic of Sichuan Provincial People's Hospital between October 2013 and May 2014 at Sichuan, China. Exploratory factor analysis and reliability tests were performed for the full version, and confirmatory factor analysis was applied for the shortened version of the C-SHQ. RESULTS: The exploratory factor analysis revealed scores loaded on 3 similar factors compared with the original SHQ. The internal consistency reliability was high (Cronbach's α = 0.99). The confirmatory factor analysis indicated that a shortened version of 12 items is sufficient to measure spatial hearing abilities. CONCLUSIONS: The C-SHQ and its short form are both reliable and valid questionnaires, which are suitable for both research and clinical settings to measure spatial hearing ability in the Chinese population.

Developmental coupling of larval and adult stages in a complex life cycle: insights from limb regeneration in the flour beetle, Tribolium castaneum.

BACKGROUND: A complex life cycle, such as complete metamorphosis, is a key innovation that can promote diversification of species. The evolution of a morphologically distinct larval stage is thought to have enabled insects to occupy broader ecological niches and become the most diverse metazoan taxon, yet the extent to which larval and adult morphologies can evolve independently remains unknown. Perturbation of larval limb regeneration allows us to generate larval legs and antennae with altered limb morphologies, which may be used to explore the developmental continuity that might exist between larval and adult appendages. In this study, we determined the roles of several appendage patterning transcription factors, abrupt (ab), dachshund (dac), Distal-less (Dll), and spineless (ss), in the red flour beetle, Tribolium castaneum, during larval appendage regeneration. The functions of these genes in regenerating and non-regenerating limbs were compared using RNA interference. RESULTS: During limb regeneration, dac and ss were necessary to re-pattern the same larval structures as those patterned during embryogenesis. Removal of these two genes led to larval appendage patterning defects that were carried over to the adult legs. Surprisingly, even though maternal knockdown of ab had minimal effects on limb allocation and patterning in the embryo, it was necessary for blastema growth, an earlier phase of regeneration. Finally, knockdown of Dll prevented the blastema-like bumps from re-differentiating into appendages. CONCLUSIONS: Our results suggest that, similar to vertebrates, the re-patterning phase of Tribolium larval limb regeneration relies on the same genes that are used during embryonic limb patterning. Thus, the re-patterning phase of regeneration is likely to be regulated by taxon-specific patterning mechanisms. Furthermore, Ab and Dll appear to play important roles during blastema proliferation and re-differentiation, respectively. Finally, our results show that continuity exists between larval and adult limb patterning, and that larval and adult leg morphologies may be developmentally coupled. Thus, the evolution of imaginal discs may have been a key step towards completely removing any developmental constraints that existed between larval and adult phenotypes.