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1.
PLoS Genet ; 18(9): e1010370, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36121880

RESUMO

The introgression of genetic traits through gene drive may serve as a powerful and widely applicable method of biological control. However, for many applications, a self-perpetuating gene drive that can spread beyond the specific target population may be undesirable and preclude use. Daisy-chain gene drives have been proposed as a means of tuning the invasiveness of a gene drive, allowing it to spread efficiently into the target population, but be self-limiting beyond that. Daisy-chain gene drives are made up of multiple independent drive elements, where each element, except one, biases the inheritance of another, forming a chain. Under ideal inheritance biasing conditions, the released drive elements remain linked in the same configuration, generating copies of most of their elements except for the last remaining link in the chain. Through mathematical modelling of populations connected by migration, we have evaluated the effect of resistance alleles, different fitness costs, reduction in the cut-rate, and maternal deposition on two alternative daisy-chain gene drive designs. We find that the self-limiting nature of daisy-chain gene drives makes their spread highly dependent on the efficiency and fidelity of the inheritance biasing mechanism. In particular, reductions in the cut-rate and the formation of non-lethal resistance alleles can cause drive elements to lose their linked configuration. This severely reduces the invasiveness of the drives and allows for phantom cutting, where an upstream drive element cuts a downstream target locus despite the corresponding drive element being absent, creating and biasing the inheritance of additional resistance alleles. This phantom cutting can be mitigated by an alternative indirect daisy-chain design. We further find that while dominant fitness costs and maternal deposition reduce daisy-chain invasiveness, if overcome with an increased release frequency, they can reduce the spread of the drive into a neighbouring population.


Assuntos
Tecnologia de Impulso Genético , Alelos , Sistemas CRISPR-Cas , Tecnologia de Impulso Genético/métodos , Mutação
2.
PLoS Genet ; 18(2): e1010060, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35180218

RESUMO

The increasing prevalence of insecticide resistance and the ongoing global burden of vector-borne diseases have encouraged new efforts in mosquito control. For Aedes aegypti, the most important arboviral vector, integration rates achieved in Cas9-based knock-ins so far have been rather low, highlighting the need to understand gene conversion patterns and other factors that influence homology-directed repair (HDR) events in this species. In this study, we report the effects of sequence mismatches or donor template forms on integration rates. We found that modest sequence differences between construct homology arms [DNA sequence in the donor template which resembles the region flanking the target cut] and genomic target comprising 1.2% nucleotide dissimilarity (heterology) significantly reduced integration rates. While most integrations (59-88%) from plasmid templates were the result of canonical [on target, perfect repair] HDR events, no canonical events were identified from other donor types (i.e. ssDNA, biotinylated ds/ssDNA). Sequencing of the transgene flanking region in 69 individuals with canonical integrations revealed 60% of conversion tracts to be unidirectional and extend up to 220 bp proximal to the break, though in three individuals bidirectional conversion of up to 725 bp was observed.


Assuntos
Sistemas CRISPR-Cas , Culicidae , Animais , Culicidae/genética , Reparo do DNA/genética , Genoma , Humanos , Mosquitos Vetores/genética
3.
Proc Natl Acad Sci U S A ; 119(46): e2206025119, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343250

RESUMO

The Lepidoptera are an insect order of cultural, economic, and environmental importance, representing ∼10% of all described living species. Yet, for all but one of these species (silkmoth, Bombyx mori), the molecular genetics of how sexual fate is determined remains unknown. We investigated this in the diamondback moth (Plutella xylostella), a globally important, highly invasive, and economically damaging pest of cruciferous crops. Our previous work uncovered a regulator of male sex determination in P. xylostella-PxyMasc, a homolog of B. mori Masculinizer-which, although initially expressed in embryos of both sexes, is then reduced in female embryos, leading to female-specific splicing of doublesex. Here, through sequencing small RNA libraries generated from early embryos and sexed larval pools, we identified a variety of small silencing RNAs (predominantly Piwi-interacting RNAs [piRNAs]) complementary to PxyMasc, whose temporal expression correlated with the reduction in PxyMasc transcript observed previously in females. Analysis of these small RNAs showed that they are expressed from tandemly arranged, multicopy arrays found exclusively on the W (female-specific) chromosome, which we term "Pxyfem". Analysis of the Pxyfem sequences showed that they are partial complementary DNAs (cDNAs) of PxyMasc messenger RNA (mRNA) transcripts, likely integrated into transposable element graveyards by the noncanonical action of retrotransposons (retrocopies), and that their apparent similarity to B. mori feminizer more probably represents convergent evolution. Our study helps elucidate the sex determination cascade in this globally important pest and highlights the "shortcuts" that retrotransposition events can facilitate in the evolution of complex molecular cascades, including sex determination.


Assuntos
Bombyx , Mariposas , Feminino , Masculino , Animais , Bombyx/genética , Bombyx/metabolismo , Mariposas/genética , Mariposas/metabolismo , Splicing de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
4.
Circulation ; 148(11): 862-871, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37555345

RESUMO

BACKGROUND: Ventricular arrhythmia is an important cause of mortality in patients with ischemic left ventricular dysfunction. Revascularization with coronary artery bypass graft or percutaneous coronary intervention is often recommended for these patients before implantation of a cardiac defibrillator because it is assumed that this may reduce the incidence of fatal and potentially fatal ventricular arrhythmias, although this premise has not been evaluated in a randomized trial to date. METHODS: Patients with severe left ventricular dysfunction, extensive coronary disease, and viable myocardium were randomly assigned to receive either percutaneous coronary intervention (PCI) plus optimal medical and device therapy (OMT) or OMT alone. The composite primary outcome was all-cause death or aborted sudden death (defined as an appropriate implantable cardioverter defibrillator therapy or a resuscitated cardiac arrest) at a minimum of 24 months, analyzed as time to first event on an intention-to-treat basis. Secondary outcomes included cardiovascular death or aborted sudden death, appropriate implantable cardioverter defibrillator (ICD) therapy or sustained ventricular arrhythmia, and number of appropriate ICD therapies. RESULTS: Between August 28, 2013, and March 19, 2020, 700 patients were enrolled across 40 centers in the United Kingdom. A total of 347 patients were assigned to the PCI+OMT group and 353 to the OMT alone group. The mean age of participants was 69 years; 88% were male; 56% had hypertension; 41% had diabetes; and 53% had a clinical history of myocardial infarction. The median left ventricular ejection fraction was 28%; 53.1% had an implantable defibrillator inserted before randomization or during follow-up. All-cause death or aborted sudden death occurred in 144 patients (41.6%) in the PCI group and 142 patients (40.2%) in the OMT group (hazard ratio, 1.03 [95% CI, 0.82-1.30]; P=0.80). There was no between-group difference in the occurrence of any of the secondary outcomes. CONCLUSIONS: PCI was not associated with a reduction in all-cause mortality or aborted sudden death. In patients with ischemic cardiomyopathy, PCI is not beneficial solely for the purpose of reducing potentially fatal ventricular arrhythmias. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01920048.


Assuntos
Desfibriladores Implantáveis , Disfunção Ventricular Esquerda , Humanos , Masculino , Idoso , Feminino , Volume Sistólico , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle , Função Ventricular Esquerda , Arritmias Cardíacas/etiologia , Disfunção Ventricular Esquerda/etiologia , Desfibriladores Implantáveis/efeitos adversos , Resultado do Tratamento
5.
Gastrointest Endosc ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935015

RESUMO

The publisher regrets that this article has been temporarily removed. A replacement will appear as soon as possible in which the reason for the removal of the article will be specified, or the article will be reinstated. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal.

6.
Proc Natl Acad Sci U S A ; 117(30): 17702-17709, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32661163

RESUMO

A dominant male-determining locus (M-locus) establishes the male sex (M/m) in the yellow fever mosquito, Aedes aegyptiNix, a gene in the M-locus, was shown to be a male-determining factor (M factor) as somatic knockout of Nix led to feminized males (M/m) while transient expression of Nix resulted in partially masculinized females (m/m), with male reproductive organs but retained female antennae. It was not clear whether any of the other 29 genes in the 1.3-Mb M-locus are also needed for complete sex-conversion. Here, we report the generation of multiple transgenic lines that express Nix under the control of its own promoter. Genetic and molecular analyses of these lines provided insights unattainable from previous transient experiments. We show that the Nix transgene alone, in the absence of the M-locus, was sufficient to convert females into males with all male-specific sexually dimorphic features and male-like gene expression. The converted m/m males are flightless, unable to perform the nuptial flight required for mating. However, they were able to father sex-converted progeny when presented with cold-anesthetized wild-type females. We show that myo-sex, a myosin heavy-chain gene also in the M-locus, was required for male flight as knockout of myo-sex rendered wild-type males flightless. We also show that Nix-mediated female-to-male conversion was 100% penetrant and stable over many generations. Therefore, Nix has great potential for developing mosquito control strategies to reduce vector populations by female-to-male sex conversion, or to aid in a sterile insect technique that requires releasing only non-biting males.


Assuntos
Aedes/genética , Voo Animal , Genes de Insetos , Estudos de Associação Genética , Proteínas de Membrana/genética , Processos de Determinação Sexual/genética , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas , Feminino , Loci Gênicos , Genótipo , Padrões de Herança , Masculino , Penetrância , Fenótipo , Regiões Promotoras Genéticas
7.
Pancreatology ; 22(8): 1091-1098, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36404201

RESUMO

INTRODUCTION: The mechanistic definition of chronic pancreatitis (CP) identifies acute pancreatitis (AP) as a precursor stage. We hypothesized that clinical AP frequently precedes the diagnosis of CP and is associated with patient- and disease-related factors. We describe the prevalence, temporal relationship and associations of AP in a well-defined North American cohort. METHODS: We evaluated data from 883 patients with CP prospectively enrolled in the North American Pancreatitis Studies across 27 US centers between 2000 and 2014. We determined how often patients had one or more episodes of AP and its occurrence in relationship to the diagnosis of CP. We used multivariable logistic regression to determine associations for prior AP. RESULTS: There were 624/883 (70.7%) patients with prior AP, among whom 161 (25.8%) had AP within 2 years, 115 (18.4%) within 3-5 years, and 348 (55.8%) >5 years prior to CP diagnosis. Among 504 AP patients with available information, 436 (86.5%) had >1 episode. On multivariable analyses, factors associated with increased odds of having prior AP were a younger age at CP diagnosis, white race, abdominal pain, pseudocyst(s) and pancreatic duct dilatation/stricture, while factors associated with a lower odds of having prior AP were exocrine insufficiency and pancreatic atrophy. When compared with patients with 1 episode, those with >1 AP episode were diagnosed with CP an average of 5 years earlier. CONCLUSIONS: Nearly three-quarters of patients were diagnosed with AP prior to CP diagnosis. Identifying which AP patients are at-risk for future progression to CP may provide opportunities for primary and secondary prevention.


Assuntos
Pancreatopatias , Pancreatite Crônica , Humanos , Doença Aguda , Pancreatite Crônica/complicações , Pancreatite Crônica/epidemiologia , Dor Abdominal
8.
J Chem Phys ; 157(16): 164105, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36319404

RESUMO

We present a means of studying rare reactive pathways in open quantum systems using transition path theory and ensembles of quantum jump trajectories. This approach allows for the elucidation of reactive paths for dissipative, nonadiabatic dynamics when the system is embedded in a Markovian environment. We detail the dominant pathways and rates of thermally activated processes and the relaxation pathways and photoyields following vertical excitation in a minimal model of a conical intersection. We find that the geometry of the conical intersection affects the electronic character of the transition state as defined through a generalization of a committor function for a thermal barrier crossing event. Similarly, the geometry changes the mechanism of relaxation following a vertical excitation. Relaxation in models resulting from small diabatic coupling proceeds through pathways dominated by pure dephasing, while those with large diabatic coupling proceed through pathways limited by dissipation. The perspective introduced here for the nonadiabatic dynamics of open quantum systems generalizes classical notions of reactive paths to fundamentally quantum mechanical processes.

9.
Proc Natl Acad Sci U S A ; 116(18): 9125-9134, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30979808

RESUMO

Carbamoyl phosphate synthetase-1 (CPS1) is the major mitochondrial urea cycle enzyme in hepatocytes. It is released into mouse and human blood during acute liver injury, where is has a short half-life. The function of CPS1 in blood and the reason for its short half-life in serum are unknown. We show that CPS1 is released normally into mouse and human bile, and pathologically into blood during acute liver injury. Other cytoplasmic and mitochondrial urea cycle enzymes are also found in normal mouse bile. Serum, bile, and purified CPS1 manifest sedimentation properties that overlap with extracellular vesicles, due to the propensity of CPS1 to aggregate despite being released primarily as a soluble protein. During liver injury, CPS1 in blood is rapidly sequestered by monocytes, leading to monocyte M2-polarization and homing to the liver independent of its enzyme activity. Recombinant CPS1 (rCPS1), but not control r-transferrin, increases hepatic macrophage numbers and phagocytic activity. Notably, rCPS1 does not activate hepatic macrophages directly; rather, it activates bone marrow and circulating monocytes that then home to the liver. rCPS1 administration prevents mouse liver damage induced by Fas ligand or acetaminophen, but this protection is absent in macrophage-deficient mice. Moreover, rCPS1 protects from acetaminophen-induced liver injury even when given therapeutically after injury induction. In summary, CPS1 is normally found in bile but is released by hepatocytes into blood upon liver damage. We demonstrate a nonenzymatic function of CPS1 as an antiinflammatory protective cytokine during acute liver injury.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Ácidos e Sais Biliares/metabolismo , Carbamoil-Fosfato Sintase (Amônia)/metabolismo , Acetaminofen/metabolismo , Lesão Pulmonar Aguda/enzimologia , Adulto , Animais , Bile/metabolismo , Citocinas/metabolismo , Proteína Ligante Fas/metabolismo , Feminino , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Hepatopatias , Macrófagos/metabolismo , Masculino , Camundongos , Mitocôndrias/metabolismo
10.
Clin Gastroenterol Hepatol ; 19(2): 349-357, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32240833

RESUMO

BACKGROUND & AIMS: Idiopathic chronic pancreatitis (ICP) is the second most common subtype of CP. In 1994, researchers reported the bimodal age at onset of ICP symptoms: early onset ICP (EO-ICP; median age, 19.2 y) and late-onset ICP (LO-ICP; median age, 56.2 y). Ages of onset and clinical features of ICP differed from those of alcohol-related CP (ACP). However, variants in PRSS1 had not yet been associated with ICP. We reexamined ages of onset of ICP in a large, North American cohort of patients, and investigated the effects of genetic factors and alcohol use in patients with EO-ICP, LO-ICP, and ACP. METHODS: We performed a cross-sectional analysis of patients with CP of European ancestry enrolled in the North American Pancreatitis Study 2, a prospective study of 1195 patients with CP from 26 centers in the United States from August 2000 through December 2014. We compared age at onset of symptoms for 130 patients with CP who were lifetime abstainers from alcohol (61 patients with early onset and 69 patients with late onset), 308 light to moderate alcohol drinkers with CP, and 225 patients with ACP and heavy to very heavy alcohol use. DNA from available patients was analyzed for variants associated with CP in SPINK1, CFTR, and CTRC. The Kruskal-Wallis test was used to compare continuous variables across groups and based on genetic variants. RESULTS: Median ages at onset of symptoms were 20 years for patients with EO-ICP and no alcohol use, 58 years for patients with LO-ICP and no alcohol use, 47 years for light to moderate alcohol drinkers with CP, and 44 years for patients with ACP. A higher proportion of patients with EO-ICP had constant pain (65%) than patients with LO-ICP (31%) (P = .04). A higher proportion of patients with ACP had pseudocysts (43%) than patients with EO-ICP (11%) (P = .001). A higher proportion of patients with EO-ICP had pathogenic variants in SPINK1, CFTR, or CTRC (49%) than patients with LO-ICP (23%), light to moderate alcohol drinking with CP (26%), or ACP (23%) (P = .001). Among patients with variants in SPINK1, those with EO-ICP had onset of symptoms at a median age of 12 years, and light to moderate alcohol drinkers with CP had an age at onset of 24 years. Among patients with variants in CFTR, light to moderate alcohol drinkers had an age at onset of symptoms of 41 years, but this variant did not affect age at onset of EO-ICP or ACP. CONCLUSIONS: We confirmed previously reported ages at onset of symptoms for EO-ICP and LO-ICP in a North American cohort. We found differences in clinical features among patients with EO-ICP, LO-ICP, and ACP. Almost half of patients with EO-ICP have genetic variants associated with CP, compared with approximately one quarter of patients with LO-CP or ACP. Genetic variants affect ages at onset of symptoms in some groups.


Assuntos
Pancreatite Crônica , Adulto , Idade de Início , Criança , Estudos Transversais , Humanos , Pessoa de Meia-Idade , América do Norte/epidemiologia , Pancreatite Crônica/complicações , Pancreatite Crônica/epidemiologia , Pancreatite Crônica/genética , Estudos Prospectivos , Tripsina , Inibidor da Tripsina Pancreática de Kazal , Adulto Jovem
11.
Conserv Biol ; 35(2): 654-665, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32537779

RESUMO

Collisions with buildings cause up to 1 billion bird fatalities annually in the United States and Canada. However, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites with standardized methods and consideration of species- and life-history-related variation and correlates of collisions. We addressed these research needs through coordinated collection of data on bird collisions with buildings at sites in the United States (35), Canada (3), and Mexico (2). We collected all carcasses and identified species. After removing records for unidentified carcasses, species lacking distribution-wide population estimates, and species with distributions overlapping fewer than 10 sites, we retained 269 carcasses of 64 species for analysis. We estimated collision vulnerability for 40 bird species with ≥2 fatalities based on their North American population abundance, distribution overlap in study sites, and sampling effort. Of 10 species we identified as most vulnerable to collisions, some have been identified previously (e.g., Black-throated Blue Warbler [Setophaga caerulescens]), whereas others emerged for the first time (e.g., White-breasted Nuthatch [Sitta carolinensis]), possibly because we used a more standardized sampling approach than past studies. Building size and glass area were positively associated with number of collisions for 5 of 8 species with enough observations to analyze independently. Vegetation around buildings influenced collisions for only 1 of those 8 species (Swainson's Thrush [Catharus ustulatus]). Life history predicted collisions; numbers of collisions were greatest for migratory, insectivorous, and woodland-inhabiting species. Our results provide new insight into the species most vulnerable to building collisions, making them potentially in greatest need of conservation attention to reduce collisions and into species- and life-history-related variation and correlates of building collisions, information that can help refine collision management.


Correlaciones de las Colisiones de Aves contra Edificios en Tres Países de América del Norte Resumen Las colisiones contra los edificios causan hasta mil millones de fatalidades de aves al año en los Estados Unidos y en Canadá. Sin embargo, los esfuerzos por reducir estas colisiones se beneficiarían con estudios realizados a grandes escalas espaciales en varios sitios de estudio con métodos estandarizados y considerando las variaciones relacionadas a la historia de vida y a la especie y las correlaciones de las colisiones. Abordamos estas necesidades de investigación por medio de una recolección coordinada de datos sobre las colisiones de aves contra edificios en los Estados Unidos (35), Canadá (3) y México (2). Recolectamos todos los cadáveres y los identificamos hasta especie. Después de retirar los registros de cadáveres no identificados, las especies sin estimaciones poblacionales a nivel distribución y las especies con distribuciones traslapadas en menos de diez sitios, nos quedamos con 269 cadáveres de 64 especies para el análisis. Estimamos la vulnerabilidad a colisiones para 40 especies con ≥2 fatalidades con base en la abundancia poblacional para América del Norte, el traslape de su distribución entre los sitios de estudio y el esfuerzo de muestreo. De las diez especies que identificamos como las más vulnerables a las colisiones, algunas han sido identificadas previamente (Setophaga caerulescens), y otras aparecieron por primera vez (Sitta carolinensis), posiblemente debido a que usamos una estrategia de muestreo más estandarizada que en los estudios previos. El tamaño del edificio y el área del vidrio estuvieron asociados positivamente con el número de colisiones para cinco de ocho especies con suficientes observaciones para ser analizadas independientemente. La vegetación alrededor de los edificios influyó sobre las colisiones solamente para una de esas ocho especies Catharus ustulatus). Las historias de vida pronosticaron las colisiones; el número de colisiones fue mayor para las especies migratorias, insectívoras y aquellas que habitan en las zonas boscosas. Nuestros resultados proporcionan una nueva perspectiva hacia las especies más vulnerables a las colisiones contra edificios, lo que las pone en una necesidad potencialmente mayor de atención conservacionista para reducir estas colisiones y de estudio de las variaciones relacionadas con la especie y la historia de vida y las correlaciones de las colisiones contra edificios, información que puede ayudar a refinar el manejo de colisiones.


Assuntos
Conservação dos Recursos Naturais , Aves Canoras , Animais , Canadá , México , América do Norte , Estados Unidos
12.
J Physiol ; 598(11): 2199-2222, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32246836

RESUMO

KEY POINTS: Kv3.1 and Kv3.3 subunits are highly expressed in the auditory brainstem, with little or no mRNA for Kv3.2 or Kv3.4. Changes in Kv3 currents and action potential (AP) firing were analysed from wild-type, Kv3.1 and Kv3.3 knockout (KO) mice. Both Kv3.1 and Kv3.3 immunostaining was present and western blots confirmed loss of subunit protein in the respective KO. Medial nucleus of the trapezoid body (MNTB) AP repolarization utilized Kv3.1 and/or Kv3.3; while in the lateral superior olive (LSO) Kv3.3 was essential. Voltage-gated calcium currents were unchanged between the genotypes. But APs evoked higher [Ca2+ ]i in LSO than MNTB neurons; and were highest in the Kv3.3KO, consistent with longer AP durations. High frequency stimulation increased AP failure rates and AP latency in LSO neurons from the Kv3.3KO, underlining the physiological consequences for binaural integration. LSO neurons require Kv3.3 for functional Kv3 channels, while MNTB neurons can utilize either Kv3.1 or Kv3.3 subunits. ABSTRACT: Kv3 voltage-gated potassium channels mediate action potential (AP) repolarization. The relative importance of Kv3.1 and Kv3.3 subunits for assembly of functional channels in neurons of the auditory brainstem was examined from the physiological perspective that speed and precision of AP firing are crucial for sound source localization. High levels of Kv3.1 and Kv3.3 mRNA and protein were measured, with no evidence of compensation by Kv3.2 or Kv3.4 in the respective knockout (KO) mouse. Using the KOs, composition of Kv3 channels was constrained to either Kv3.1 or Kv3.3 subunits in principal neurons of the medial nucleus of the trapezoid body (MNTB) and lateral superior olive (LSO); while TEA (1 mm) was employed to block Kv3-mediated outward potassium currents in voltage- and current clamp experiments. MNTB neuron APs (half-width 0.31 ± 0.08 ms, n = 25) were fast, reliable, and showed no distinction between channels assembled from Kv3.1 or Kv3.3 subunits (in the respective KO). LSO AP half-widths were also fast, but absolutely required Kv3.3 subunits for fast repolarization (half-widths: 0.25 ± 0.08 ms, n = 19 wild-type, 0.60 ± 0.17 ms, n = 21 Kv3.3KO, p = 0.0001). The longer AP duration increased LSO calcium influx and AP failure rates, and increased AP latency and jitter during high frequency repetitive firing. Both Kv3.1 and Kv3.3 subunits contribute to Kv3 channels in the MNTB (and compensate for each other in each KO); in contrast, LSO neurons require Kv3.3 subunits for fast repolarization and to sustain AP firing during high frequency stimulation. In conclusion, Kv3 channels exhibit both redundancy and Kv3.3 dominance between the brainstem nuclei involved in sound localization.


Assuntos
Vias Auditivas , Corpo Trapezoide , Potenciais de Ação , Animais , Tronco Encefálico , Camundongos , Neurônios
13.
Pancreatology ; 20(7): 1368-1378, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32967795

RESUMO

BACKGROUND: Chronic pancreatitis (CP) is a complex inflammatory disorder of the pancreas affecting acinar cells, duct cells, islet cells and inflammatory cells including fibrosis-producing stellate cells. Serum trypsinogen is a biomarkers of acinar cell function. AIM: To define the degree of correlation between low trypsinogen levels as a marker of acinar cell function and variable features of CP. METHODS: Serum samples from previously ascertained and well phenotyped case and control subjects from the North American Pancreatitis Study II (NAPS2) were used to measure serum trypsinogen levels in a commercial laboratory. Control samples were used to define normal ranges and compared with levels in CP patients with defined features. RESULTS: A final cohort of 279 CP patients and 262 controls from the NAPS2 studies were evaluated. In controls trypsinogen had a mean of 34.96 ng/ml and SD = 11.99. Cut-off values for low trypsinogen ranged from <20 to 10 ng/ml and very low trypsinogen at <10 ng/ml. Compared to controls, CP was associated with very low trypsinogen levels (p < 0.0001). Within CP, very low trypsinogen levels correlated with parenchymal loss (pancreatic surgery [p < 0.05]; atrophy with calcifications, [p < 0.001]), EPI (p < 0.01, trend p < 0.001) and diabetes (trend p < 0.01) but not CT-based criteria for fibrosis (pancreatic duct dilation, irregularity, strictures). CONCLUSIONS: Very low serum trypsinogen levels correlate with measures of acinar cell loss including surgical resection, atrophic-calcific CP, diabetes and functional symptoms EPI but not duct morphology criteria. Serum trypsinogen levels correlate with decreased acinar cell function and therefore have biomarker utility clinical management.


Assuntos
Complicações do Diabetes/sangue , Insuficiência Pancreática Exócrina/sangue , Pancreatite Crônica/sangue , Pancreatite Crônica/diagnóstico por imagem , Tripsinogênio/sangue , Células Acinares , Adulto , Idoso , Atrofia , Biomarcadores/sangue , Calcinose/patologia , Estudos de Coortes , Insuficiência Pancreática Exócrina/patologia , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Ductos Pancreáticos/patologia , Pancreatite Crônica/patologia , Índice de Gravidade de Doença , Inquéritos e Questionários , Tomografia Computadorizada por Raios X
14.
Pancreatology ; 19(4): 500-506, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30910452

RESUMO

BACKGROUND: We have previously reported that physicians under-recognize smoking as a chronic pancreatitis (CP) risk factor. We hypothesized that availability of empiric data will influence physician recognition of this relationship. METHODS: We analyzed data from 508 CP patients prospectively enrolled in the North American Pancreatitis Study-2 Continuation and Validation (NAPS2-CV) or NAPS2-Ancillary (AS) studies (2008-2014) from 26 US centers who self-reported ever-smoking. Information on smoking status, physician-defined etiology and identification of smoking as a CP risk factor was obtained from structured patient and physician questionnaires. We compared how often physician identified smoking as a CP risk factor in NAPS2-CV/NAPS2-AS studies with NAPS2-original study (2000-2006). RESULTS: Enrolling physician identified smoking as a risk factor in significantly (all p < 0.001) greater proportion of patients in NAPS2-CV/AS studies when compared with NAPS2-original study among ever (80.7 vs. 45.3%), current (91.3 vs. 53%), past (60.3 vs. 30.2%) smokers, in those who smoked ≤1 pack/day (79.3 vs. 39.5%) or ≥1 packs/day (83 vs. 49.8%). In multivariable analyses, the enrolling physician was 3.32-8.49 times more likely to cite smoking as a CP risk factor in the NAPS2-CV/NAPS2-AS studies based on smoking status and amount after controlling for age, sex, race and alcohol etiology. The effect was independent of enrolling site in a sub-analysis limited to sites participating in both phases of enrollment. CONCLUSIONS: Availability of empiric data likely enhanced physician recognition of the association between smoking and CP. Wide-spread dissemination of this information could potentially curtail smoking rates in subjects with and those at risk of CP.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pancreatite Crônica/etiologia , Médicos , Fumar/efeitos adversos , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pancreatite Crônica/tratamento farmacológico , Fatores de Risco , Autorrelato , Inquéritos e Questionários
15.
Gastrointest Endosc ; 90(1): 13-26, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31122744

RESUMO

Interest in the use of simulation for acquiring, maintaining, and assessing skills in GI endoscopy has grown over the past decade, as evidenced by recent American Society for Gastrointestinal Endoscopy (ASGE) guidelines encouraging the use of endoscopy simulation training and its incorporation into training standards by a key accreditation organization. An EndoVators Summit, partially supported by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the National Institutes of Health, (NIH) was held at the ASGE Institute for Training and Technology from November 19 to 20, 2017. The summit brought together over 70 thought leaders in simulation research and simulator development and key decision makers from industry. Proceedings opened with a historical review of the role of simulation in medicine and an outline of priority areas related to the emerging role of simulation training within medicine broadly. Subsequent sessions addressed the summit's purposes: to review the current state of endoscopy simulation and the role it could play in endoscopic training, to define the role and value of simulators in the future of endoscopic training and to reach consensus regarding priority areas for simulation-related education and research and simulator development. This white paper provides an overview of the central points raised by presenters, synthesizes the discussions on the key issues under consideration, and outlines actionable items and/or areas of consensus reached by summit participants and society leadership pertinent to each session. The goal was to provide a working roadmap for the developers of simulators, the investigators who strive to define the optimal use of endoscopy-related simulation and assess its impact on educational outcomes and health care quality, and the educators who seek to enhance integration of simulation into training and practice.


Assuntos
Endoscopia Gastrointestinal/educação , Gastroenterologia/educação , Treinamento por Simulação , Humanos
16.
Gastrointest Endosc ; 89(5): 977-983.e2, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30465770

RESUMO

BACKGROUND AND AIMS: Markedly increased liver chemistries in patients presenting with acute calculous cholecystitis (AC) often prompt an evaluation for concomitant choledocholithiasis (CDL). However, current guidelines directing the workup for CDL fail to address this unique population. The aims of this study are to define the range of presenting laboratory values and imaging findings in AC, develop a model to predict the presence of concurrent CDL, and develop a management algorithm that can be easily applied on presentation. METHODS: We conducted a retrospective review of patients presenting with AC to a large tertiary hospital over a 3.5-year period. CDL was defined as common bile duct (CBD) stone(s), sludge, or debris seen on any of the following studies: US, CT, magnetic resonance imaging/MRCP, EUS, ERCP, or intraoperative cholangiogram. A multivariable model to predict CDL was developed on 70% of the patients and validated on the remaining 30%. RESULTS: A total of 366 patients were identified and 65 (17.8%) had concurrent CDL. Univariable analysis was used to predict CDL and demonstrated statistically significant odds ratios for transaminases >3 times the upper limit of normal, alkaline phosphatase (AlkPhos) above normal, lipase >3 times the upper limit of normal, total bilirubin ≥1.8 mg/dL, and CBD diameter >6 mm. In the validation cohort, an optimal model containing alanine transaminase (ALT) >3 times the upper limit of normal, abnormal AlkPhos, and CBD diameter >6 mm was found to have an area under the receiver operating curve of 0.91. When 0 or 1 risk factors were present, 98.6% of patients did not have CDL. When all 3 risk factors were present, 77.8% were found to have CDL. CONCLUSIONS: The prevalence of CDL is high among patients with AC. When a validated model is used, application of cutoffs for ALT, AlkPhos, and CBD diameter can effectively triage patients with low and high likelihood for CDL to surgery or ERCP, respectively.


Assuntos
Colecistectomia/métodos , Colecistite Aguda/diagnóstico por imagem , Colecistite Aguda/epidemiologia , Coledocolitíase/epidemiologia , Coledocolitíase/cirurgia , Centros Médicos Acadêmicos , Adulto , Fatores Etários , Idoso , Algoritmos , Análise de Variância , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Colangiopancreatografia por Ressonância Magnética/métodos , Colecistectomia/efeitos adversos , Colecistite Aguda/cirurgia , Coledocolitíase/diagnóstico por imagem , Estudos de Coortes , Comorbidade , Feminino , Humanos , Testes de Função Hepática , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Prognóstico , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Resultado do Tratamento , Estados Unidos
17.
J Pediatr Gastroenterol Nutr ; 68(4): 566-573, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30897605

RESUMO

OBJECTIVES: The aim of the present study was to investigate the natural history of chronic pancreatitis (CP); patients in the North American Pancreatitis Study2 (NAPS2, adults) and INternational Study group of Pediatric Pancreatitis: In search for a cuRE (INSPPIRE, pediatric) were compared. METHODS: Demographics, risk factors, disease duration, management and outcomes of 224 children and 1063 adults were compared using appropriate statistical tests for categorical and continuous variables. RESULTS: Alcohol was a risk in 53% of adults and 1% of children (P < 0.0001); tobacco in 50% of adults and 7% of children (P < 0.0001). Obstructive factors were more common in children (29% vs 19% in adults, P = 0.001). Genetic risk factors were found more often in children. Exocrine pancreatic insufficiency was similar (children 26% vs adult 33%, P = 0.107). Diabetes was more common in adults than children (36% vs 4% respectively, P < 0.0001). Median emergency room visits, hospitalizations, and missed days of work/school were similar across the cohorts. As a secondary analysis, NAPS2 subjects with childhood onset (NAPS2-CO) were compared with INSPPIRE subjects. These 2 cohorts were more similar than the total INSPPIRE and NAPS2 cohorts, including for genetic risk factors. The only risk factor significantly more common in the NAPS2-CO cohort compared with the INSPPIRE cohort was alcohol (9% NAPS2-CO vs 1% INSPPIRE cohorts, P = 0.011). CONCLUSIONS: Despite disparity in age of onset, children and adults with CP exhibit similarity in demographics, CP treatment, and pain. Differences between groups in radiographic findings and diabetes prevalence may be related to differences in risk factors associated with disease and length of time of CP.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Pancreatite Crônica/epidemiologia , Pancreatite Crônica/etiologia , Fumar Tabaco/efeitos adversos , Adolescente , Adulto , Criança , Estudos de Coortes , Estudos Transversais , Demografia , Progressão da Doença , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Pancreatite Crônica/genética , Pancreatite Crônica/fisiopatologia , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários
18.
Anesth Analg ; 128(4): 661-668, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29324491

RESUMO

BACKGROUND: Cerebral oximetry using near-infrared spectroscopy is a noninvasive optical technology to detect cerebral hypoxia-ischemia and develop interventions to prevent and ameliorate hypoxic brain injury. Cerebral oximeters are calibrated and validated by comparison of the near-infrared spectroscopy-measured cerebral O2 saturation (SctO2) to a "field" or reference O2 saturation (REF CX) calculated as a weighted average from arterial and jugular bulb oxygen saturations. In this study, we calibrated and validated the second-generation, 5 wavelength, FORE-SIGHT Elite with the medium sensor (source-detector separation 12 and 40 mm) for measurement of SctO2 in children with congenital heart disease. METHODS: After institutional review board approval and written informed consent, 63 children older than 1 month and ≥2.5 kg scheduled for cardiac catheterization were enrolled. Self-adhesive FORE-SIGHT Elite medium sensors were placed on the right and left sides of the forehead. Blood samples for calculation of REF CX were drawn simultaneously from the aorta or femoral artery and the jugular bulb before (T1) and shortly after (T2) baseline hemodynamic measurements. FORE-SIGHT Elite SctO2 measurements were compared to the REF CX (REF CX = [0.3 SaO2] + [0.7 SjbO2]) using Deming regression, least squares linear regression, and Bland-Altman analysis. RESULTS: Sixty-one subjects (4.5 [standard deviation 4.4] years of age; 17 [standard deviation 13] kg, male 56%) completed the study protocol. Arterial oxygen saturation ranged from 64.7% to 99.1% (median 96.0%), jugular bulb venous oxygen saturation from 34.1% to 88.1% (median 68.2%), the REF CX from 43.8% to 91.4% (median 76.9%), and the SctO2 from 47.8% to 90.8% (median 76.3%). There was a high degree of correlation in SctO2 between the right and left sensors at a given time point (within subject between sensor correlation r = 0.91 and 95% confidence interval [CI], 0.85-0.94) or between T1 and T2 for the right and left sensors (replicates, within subject between time point correlation r = 0.95 and 95% CI, 0.92-0.96). By Deming regression, the estimated slope was 0.966 (95% CI, 0.786-1.147; P = .706 for testing against null hypothesis of slope = 1) with a y intercept of 2.776 (95% CI, -11.102 to 16.654; P = .689). The concordance correlation coefficient was 0.873 (95% CI, 0.798-0.922). Bland-Altman analysis for agreement between SctO2 and REF CX that accounted for repeated measures (both in times and sensors) found a bias of -0.30% (95% limits of agreement: -10.56% to 9.95%). CONCLUSIONS: This study calibrated and validated the FORE-SIGHT Elite tissue oximeter to accurately measure SctO2 in pediatric patients with the medium sensor.


Assuntos
Cardiopatias Congênitas/diagnóstico , Oximetria/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adolescente , Encéfalo/irrigação sanguínea , Lesões Encefálicas/patologia , Calibragem , Cateterismo Cardíaco , Circulação Cerebrovascular , Criança , Pré-Escolar , Desenho de Equipamento , Feminino , Humanos , Hipóxia/diagnóstico , Hipóxia-Isquemia Encefálica , Lactente , Masculino , Oximetria/métodos , Oxigênio/metabolismo , Análise de Regressão , Reprodutibilidade dos Testes
19.
Endocr Pract ; 25(7): 698-716, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30865522

RESUMO

Objective: Albiglutide, a glucagon-like peptide-1 receptor agonist (GLP-1RA), reduces glycated hemoglobin with a low risk of hypoglycemia in patients with type 2 diabetes. The relationship between GLP-1RAs and risk of pancreatitis is unresolved. This independent, rigorous, expert review of the albiglutide HARMONY Phase III clinical program examined suspected cases of acute pancreatitis. Methods: An independent pancreatitis adjudication committee (PAC), composed of physicians with expertise in gastroenterology and pancreatic disease, was prospectively established to review cases of suspected acute pancreatitis in the HARMONY studies. Results: Patients treated in Phase III trials with albiglutide (n = 2,365), or active or placebo comparators (n = 2,530), averaged 56 years of age with a mean 8.3-year diabetes duration. Across the 8 studies, the PAC reviewed potential cases of treatment-emergent acute pancreatitis in 43 patients. Definite or probable acute pancreatitis was adjudicated for 11 patients (8 albiglutide; 3 active comparators). Most of these were considered by the PAC to be at least possibly related to study treatment (6 of 8 albiglutide cases and 2 of 3 active comparator cases). Both cases in the active comparator group adjudicated as definite or probable pancreatitis with at least a possible relationship to study treatment were in patients treated with a GLP-1RA. The frequency of pancreatitis was higher among patients treated with albiglutide (6/2,365, 0.3%) than with placebo (0/486, 0%) or active comparators (2/2,062, 0.08%). Conclusion: In the HARMONY Phase III program, adjudicated cases of acute pancreatitis were uncommon. However, within the limitations of available data, the incidence of acute pancreatitis with albiglutide appears to be within the range described for other studies of GLP-1RAs. Abbreviations: AE = adverse event; CI = confidence interval; DPP-4 = dipeptidyl peptidase-4; GLP-1 = glucagon-like peptide-1; GLP-1RA = glucagon-like peptide-1 receptor agonist; MH-OR = Mantel-Haenszel odds ratio; OR = odds ratio; PAC = pancreatitis adjudication committee; SAE = serious adverse event; ULN = upper limit of normal.


Assuntos
Diabetes Mellitus Tipo 2 , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/efeitos adversos , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos , Hipoglicemiantes , Pessoa de Meia-Idade , Pâncreas
20.
Am J Gastroenterol ; 113(6): 906-912, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29867178

RESUMO

OBJECTIVES: The impact of recurrent acute pancreatitis (RAP) on quality of life (QOL) is unknown. We hypothesized that RAP would reduce QOL even in the absence of chronic pancreatitis (CP). METHODS: Data were pooled from three prospective, cross-sectional studies conducted across 27 U.S. centers (the North American Pancreatitis Studies); these included subjects with chronic pancreatitis (n = 1086), RAP alone (n = 508), and non-disease controls (n = 1025). QOL was measured using the Short Form 12 (SF-12), generating a Physical Component Summary (PCS) and the Mental Component Summary score (MCS). Multivariable regression models were developed to measure the effect of RAP on QOL, the predictors of lower QOL in those with RAP, and the differential effect QOL predictors between CP and RAP. RESULTS: Compared to controls (51.0 ± 9.4), subjects with RAP (41.1 ± 11.4) and CP (37.2 ± 11.8) had lower PCS (p < 0.01). Subjects with CP had lower PCS compared to those with RAP (p < 0.01). Similarly, MCS was lower among RAP (44.6 ± 11.5) and CP (42.8 ± 12.2) subjects compared to controls (51.7 ± 9.1, p < 0.01). Subjects with CP had lower MCS compared to those with RAP (p < 0.01). After controlling for independent predictors of PCS, RAP was associated with lower PCS (estimate -8.46, p < 0.01) and MCS (estimate -6.45, p < 0.0001) compared to controls. The effect of endocrine insufficiency on PCS was differentially greater among RAP subjects (-1.28 for CP vs. -4.9 for RAP, p = 0.0184). CONCLUSIONS: Even in the absence of CP, subjects with RAP have lower physical and mental QOL. This underscores the importance of identifying interventions to attenuate RAP before the development of overt CP.


Assuntos
Pancreatite/complicações , Qualidade de Vida , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/patologia , Pancreatite/psicologia , Estudos Prospectivos , Recidiva , Fatores de Risco
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