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1.
Gastrointest Endosc ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935016

RESUMO

BACKGROUND AND AIMS: Training in interventional endoscopy is offered by nonaccredited advanced endoscopy fellowship programs (AEFPs). The number of these programs has increased dramatically with a concurrent increase in the breadth and complexity of interventional endoscopy procedures. Accreditation is governed by competency-based education, yet what constitutes a "high-quality" nonaccredited AEFP has not been defined. Using an evidence-based consensus process, we aimed to establish standards for AEFPs. METHODS: The RAND UCLA appropriateness method, a well-described modified Delphi process to develop quality indicators, was used. A task force established by the American Society for Gastrointestinal Endoscopy drafted potential quality indicators (structure, process, and outcome) in 6 categories: activity preceding training; structure of AEFPs; training in ERCP, EUS, and EMR; and luminal stent placement. Three rounds of iterative feedback from 20 experts were conducted. Round 0 involved discussion of project details. In round 1, experts independently ranked proposed quality indicators on a 9-point interval scale ranging from highly inappropriate (1) to highly appropriate (9). Next, proposed quality indicators were discussed and reworded in a group meeting followed by round 2, in which experts independently reranked proposed quality indicators and provided benchmarks (when applicable). The median score for each quality indicator was calculated. Mean absolute deviation from the median was calculated, and appropriateness of potential quality indicators was assessed using the BIOMED concerted action on appropriateness definition, P value method, and interpercentile range adjusted for symmetry definition. A quality indicator was deemed appropriate if the median score was ≥7 and met criteria for appropriateness using all 3 defined statistical methods. RESULTS: Of 89 proposed quality indicators, 37 statements met criteria as appropriate for a quality indicator (activity preceding training, 2; structure of AEFPs, 10; training in ERCP, 7; training in EUS, 8; training in EMR, 7; luminal stent placement, 3). Minimum thresholds were defined for 19 relevant quality indicators for number of trainers, procedures during fellowship, and procedures before assessment of competence. Among the final appropriate quality indicators were that all trainees should undergo qualitative and quantitative competence assessments using validated tools at least quarterly with documented feedback throughout the training period and that trainees should track outcomes and relevant quality metrics for specific procedures. CONCLUSIONS: This consensus process using validated methodology established standards for an AEFP in an effort to ensure adequate training in the most commonly taught interventional endoscopic procedures (ERCP, EUS, EMR, and luminal stent placement) during fellowship. An important component of an AEFP is the use of competency-based assessments that are compliant with the Accreditation Council for Graduate Medical Education's Next Accreditation System, with the goal of ensuring that trainees achieve specific milestones in their progression to achieving cognitive and technical competency.

2.
Pharmacol Res ; 185: 106474, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36179954

RESUMO

Blockade of cannabinoid type 1 (CB1)-receptor signaling decreases the rewarding properties of many drugs of abuse and has been proposed as an anti-addiction strategy. However, psychiatric side-effects limit the clinical potential of orthosteric CB1 antagonists. Negative allosteric modulators (NAMs) represent a novel and indirect approach to attenuate CB1 signaling by decreasing affinity and/or efficacy of CB1 ligands. We hypothesized that a CB1-NAM would block opioid reward while avoiding the unwanted effects of orthosteric CB1 antagonists. GAT358, a CB1-NAM, failed to elicit cardinal signs of direct CB1 activation or inactivation when administered by itself. GAT358 decreased catalepsy and hypothermia but not antinociception produced by the orthosteric CB1 agonist CP55,940, suggesting that a CB1-NAM blocked cardinal signs of CB1 activation. Next, GAT358 was evaluated using in vivo assays of opioid-induced dopamine release and reward in male rodents. In the nucleus accumbens shell, a key component of the mesocorticolimbic reward pathway, morphine increased electrically-evoked dopamine efflux and this effect was blocked by a dose of GAT358 that lacked intrinsic effects on evoked dopamine efflux. Moreover, GAT358 blocked morphine-induced reward in a conditioned place preference (CPP) assay without producing reward or aversion alone. GAT358-induced blockade of morphine CPP was also occluded by GAT229, a CB1 positive allosteric modulator (CB1-PAM), and absent in CB1-knockout mice. Finally, GAT358 also reduced oral oxycodone (but not water) consumption in a two-bottle choice paradigm. Our results support the therapeutic potential of CB1-NAMs as novel drug candidates aimed at preventing opioid reward and treating opioid abuse while avoiding unwanted side-effects.


Assuntos
Analgésicos Opioides , Dopamina , Camundongos , Animais , Masculino , Analgésicos Opioides/farmacologia , Recompensa , Morfina/farmacologia , Camundongos Knockout , Receptores de Canabinoides , Receptor CB1 de Canabinoide
3.
Am J Obstet Gynecol ; 225(5): 527.e1-527.e12, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33957116

RESUMO

BACKGROUND: The American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine recently recommended offering genetic counseling and diagnostic testing for enlarged nuchal translucency at ≥3.0 mm, regardless of previous negative screening with noninvasive prenatal testing. OBJECTIVE: This study aimed to perform a population-based, individual record linkage study to determine the optimal definition of an enlarged nuchal translucency for the detection of atypical chromosome abnormalities. STUDY DESIGN: This was a retrospective study of women resident in Victoria, Australia, undergoing combined first-trimester screening during the 24-month period from January 2015 to December 2016. Linkages between statewide results for combined first-trimester screening, prenatal diagnostic procedures, and postnatal cytogenetic results from products of conception and infants up to 12 months of age were used to ascertain the frequency and type of chromosome abnormality by gestation and nuchal translucency measurement. An atypical chromosome abnormality was defined as any major chromosome abnormality other than whole chromosome aneuploidy involving chromosomes 21, 18, 13, X, and Y. RESULTS: Of the 81,244 singleton pregnancies undergoing combined first-trimester screening, 491 (0.60%) had a nuchal translucency of ≥3.5 mm, 534 (0.66%) had a nuchal translucency of 3.0 to 3.4 mm, and 80,219 (98.74%) had a nuchal translucency of < 3.0 mm. When grouped by nuchal translucency multiples of the median (MoM), 192 (0.24%) had a nuchal translucency of ≥3.0 MoM, 513 (0.63%) had a nuchal translucency of 1.9 to 2.9 MoM, and 80,539 (99.13%) had a nuchal translucency of <1.9 MoM. A total of 1779 pregnancies underwent prenatal or postnatal diagnostic testing, of which 89.60% were performed by whole-genome single-nucleotide polymorphism chromosomal microarray. The frequency of total major chromosome abnormalities was significantly higher in the group with a nuchal translucency of ≥3.5 mm (147 of 491, 29.94%) than the group with a nuchal translucency of 3.0 to 3.4 mm (21 of 534, 3.93%) or a nuchal translucency of <3.0 mm (71 of 80,219, 0.09%) (P<.001). There were 93 atypical chromosome abnormalities in the total screened cohort. The frequency of an atypical chromosome abnormality was 4.07% (95% confidence interval, 2.51-6.22), 0.37% (95% confidence interval, 0.05-1.35), and 0.09% (95% confidence interval, 0.07-0.11) in the groups with a nuchal translucency of ≥3.5 mm, 3.0 to 3.4 mm, and <3.0 mm, respectively. The frequency of atypical chromosome abnormalities was 4.69% (95% confidence interval, 2.17-8.71), 2.53% (95% confidence interval, 1.36-4.29), and 0.09% (95% confidence interval, 0.07-0.11) in the groups with a nuchal translucency of ≥3.0 MoM, 1.9 to 2.9 MoM, and <1.9 MoM, respectively. When defining thresholds for offering diagnosis with chromosomal microarray at 11 to 13 weeks, both a nuchal translucency threshold of 1.9 MoM and a fixed threshold of 3.0 mm captured 22 of 93 fetuses (23.7%) with an atypical chromosome abnormality. Of these, 50.0% had a coexisting fetal abnormality on ultrasound. However, the gestation-specific threshold of 1.9 MoM had a better specificity than 3.0 mm. The positive predictive value of an enlarged nuchal translucency for any atypical chromosome abnormality was 1 in 47 for nuchal translucency of >3.0 mm and 1 in 32 for nuchal translucency of >1.9 MoM. Our nuchal translucency threshold of 1.9 MoM captured 0.87% of fetuses, thus approximating the 99th centile. CONCLUSION: A gestational age-adjusted nuchal translucency threshold of 1.9 MoM or 99th centile is superior to the fixed cutoff of 3.0 mm for the identification of atypical chromosome abnormalities. The risk of an atypical chromosome abnormality in a fetus with an enlarged nuchal translucency is more than tripled in the presence of an additional ultrasound abnormality.


Assuntos
Ácidos Nucleicos Livres , Aberrações Cromossômicas , Teste Pré-Natal não Invasivo/métodos , Medição da Translucência Nucal , Análise de Sequência com Séries de Oligonucleotídeos , Adolescente , Adulto , Austrália , Feminino , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Gravidez , Primeiro Trimestre da Gravidez , Estudos Retrospectivos , Adulto Jovem
4.
Hum Reprod ; 35(3): 694-704, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32207823

RESUMO

STUDY QUESTION: What is the frequency of major chromosome abnormalities in a population-based diagnostic data set of genomic tests performed on miscarriage, fetal and infant samples in a state with >73 000 annual births? SUMMARY ANSWER: The overall frequency of major chromosome abnormalities in the entire cohort was 28.2% (2493/8826), with a significant decrease in the detection of major chromosome abnormalities with later developmental stage, from 50.9% to 21.3% to 15.6% of tests in the miscarriage, prenatal and postnatal cohorts, respectively. WHAT IS KNOWN ALREADY: Over the past decade, technological advances have revolutionized genomic testing at every stage of reproduction. Chromosomal microarrays (CMAs) are now the gold standard of chromosome assessment in prenatal diagnosis and pediatrics. STUDY DESIGN, SIZE, DURATION: A population-based cohort study including all chromosome analysis was performed in the Australian state of Victoria during a 24-month period from January 2015 to December 2016. All samples obtained via invasive prenatal diagnosis and postnatal samples from pregnancy tissue and infants ≤12 months of age were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: A research collaboration of screening and diagnostic units in the Australian state of Victoria was formed (the Perinatal Record Linkage collaboration), capturing all instances of prenatal and postnatal chromosome testing performed in the state. Victoria has over 73 000 births per annum and a median maternal age of 31.5 years. We analyzed our population-based diagnostic data set for (i) chromosome assessment of miscarriage, prenatal diagnosis and postnatal samples; (ii) testing indications and diagnostic yields for each of these cohorts; (iii) and the combined prenatal/infant prevalence of 22q11.2 deletion syndrome (DS) as a proportion of all births ≥20 weeks gestation. MAIN RESULTS AND THE ROLE OF CHANCE: During the 24-month study period, a total of 8826 chromosomal analyses were performed on prenatal and postnatal specimens in Victoria. The vast majority (91.2%) of all chromosome analyses were performed with CMA.The overall frequency of major chromosome abnormalities in the entire cohort was 28.2% (2493/8826). There was a significant decreasing trend in the percentage of chromosome abnormalities with later developmental stage from 50.9% to 21.3% to 15.6% in the miscarriage, prenatal and postnatal cohorts, respectively (χ2 trend = 790.0, P < 0.0001). The total frequency of abnormalities in the live infant subgroup was 13.4% (244/1816). The frequencies of pathogenic copy number variants (CNVs) detected via CMA for the miscarriage, prenatal and postnatal cohorts were 1.9% (50/2573), 2.2% (82/3661) and 4.9% (127/2592), respectively. There was a significant increasing trend in the frequency of pathogenic CNVs with later developmental stage (χ2 trend = 39.72, P < 0.0001). For the subgroup of live infants, the pathogenic CNV frequency on CMA analysis was 6.0% (109/1816). There were 38 diagnoses of 22q11.2 DS, including 1 miscarriage, 15 prenatal and 22 postnatal cases. After excluding the miscarriage case and accounting for duplicate testing, the estimated prevalence of 22q11 DS was 1 in 4558 Victorian births. LIMITATIONS, REASONS FOR CAUTION: Clinical information was missing on 11.6% of postnatal samples, and gestational age was rarely provided on the miscarriage specimens. We were unable to obtain rates of termination of pregnancy and stillbirth in our cohort due to incomplete data provided by clinical referrers. We therefore cannot make conclusions on pregnancy or infant outcome following diagnostic testing. Childhood and adult diagnoses of 22q11 DS were not collected. WIDER IMPLICATIONS OF THE FINDINGS: Our study marks a complete transition in genomic testing from the G-banded karyotype era, with CMA now established as the first line investigation for pregnancy losses, fetal diagnosis and newborn/infant assessment in a high-income setting. Integration of prenatal and postnatal diagnostic data sets provides important opportunities for estimating the prevalence of clinically important congenital syndromes, such as 22q11 DS. STUDY FUNDING/COMPETING INTEREST(S): L.H. is funded by a National Health and Medical Research Council Early Career Fellowship (1105603); A.L. was funded by a Mercy Perinatal Research Fellowship; J.H. was funded by a National Health and Medical Research Council Senior Research Fellowship (10121252). The funding bodies had no role in the conduct of the research or the manuscript. Discretionary funding from the Murdoch Children's Research Institute has supported the prenatal diagnosis data collection and reporting over the years.Dr Ricardo Palma-Dias reports a commercial relationship with Roche Diagnostics, personal fees from Philips Ultrasound, outside the submitted work. Debbie Nisbet reports a commercial relationship with Roche Diagnostics, outside the submitted work. TRIAL REGISTRATION NUMBER: NA.


Assuntos
Síndrome da Deleção 22q11 , Aberrações Cromossômicas , Adulto , Austrália/epidemiologia , Criança , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Gravidez , Prevalência
5.
J Pharmacol Exp Ther ; 370(2): 252-268, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31175218

RESUMO

Homomeric α7 nicotinic acetylcholine receptors (nAChR) have an intrinsically low probability of opening that can be overcome by α7-selective positive allosteric modulators (PAMs), which bind at a site involving the second transmembrane domain (TM2). Mutation of a methionine that is unique to α7 at the 15' position of TM2 to leucine, the residue in most other nAChR subunits, largely eliminates the activity of such PAMs. We tested the effect of the reverse mutation (L15'M) in heteromeric nAChR receptors containing α4 and ß2, which are the nAChR subunits that are most abundant in the brain. Receptors containing these mutations were found to be strongly potentiated by the α7 PAM 3a,4,5,9b-tetrahydro-4-(1-naphthalenyl)-3H-cyclopentan[c]quinoline-8-sulfonamide (TQS) but insensitive to the alternative PAM 1-(5-chloro-2,4-dimethoxyphenyl)-3-(5-methylisoxazol-3-yl)-urea. The presence of the mutation in the ß2 subunit was necessary and sufficient for TQS sensitivity. The primary effect of the mutation in the α4 subunit was to reduce responses to acetylcholine applied alone. Sensitivity to TQS required only a single mutant ß subunit, regardless of the position of the mutant ß subunit within the pentameric complex. Similar results were obtained when ß2L15'M was coexpressed with α2 or α3 and when the L15'M mutation was placed in ß4 and coexpressed with α2, α3, or α4. Functional receptors were not observed when ß1L15'M subunits were coexpressed with other muscle nAChR subunits. The unique structure-activity relationship of PAMs and the α4ß2L15'M receptor compared with α7 and the availability of high-resolution α4ß2 structures may provide new insights into the fundamental mechanisms of nAChR allosteric potentiation. SIGNIFICANCE STATEMENT: Heteromeric neuronal nAChRs have a relatively high initial probability of channel activation compared to receptors that are homomers of α7 subunits but are insensitive to PAMs, which greatly increase the open probability of α7 receptors. These features of heteromeric nAChR can be reversed by mutation of a single residue present in all neuronal heteromeric nAChR subunits to the sequence found in α7. Specifically, the mutation of the TM2 15' leucine to methionine in α subunits reduces heteromeric receptor channel activation, while the same mutation in neuronal ß subunits allows heteromeric receptors to respond to select α7 PAMs. The results indicate a key role for this residue in the functional differences in the two main classes of neuronal nAChRs.


Assuntos
Mutação , Neurônios/metabolismo , Multimerização Proteica , Subunidades Proteicas/genética , Receptor Nicotínico de Acetilcolina alfa7/química , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Regulação Alostérica/genética , Sequência de Aminoácidos , Animais , Humanos , Modelos Moleculares , Estrutura Quaternária de Proteína , Receptor Nicotínico de Acetilcolina alfa7/genética
6.
Prenat Diagn ; 39(13): 1254-1261, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31691307

RESUMO

OBJECTIVES: To explore the association between timing of diagnosis of common autosomal trisomies, maternal age, and socio-economic status (SES). DESIGN: Retrospective study of cytogenetic diagnoses of trisomy 21 (T21), trisomy 18 (T18), and trisomy 13 (T13) in Victoria, Australia, in 2015 to 2016, stratified by timing (prenatal less than 17 weeks gestation, prenatal including or greater than or 17 weeks gestation, and postnatal before 12 months of age), maternal age, and SES region. Utilisation of prenatal testing following a live-born T21 infant was ascertained via record linkage. RESULTS: Among 160 230 total births were 571 diagnoses of T21 and 246 of T18/T13. The overall and live birth prevalences of T21 were 3.56 and 0.47 per 1000 births, respectively. Compared with women from disadvantaged SES regions, women from high SES regions were more likely to have a prenatal diagnosis of a trisomy before 17 weeks than after (P < .01) and less likely to have a live-born T21 infant than a prenatal diagnosis (P < .01). There was a significant trend to higher live birth rates of T21 with lower SES (P = .004). The majority (68.5%) of women who gave birth to a live infant with T21 did not utilise prenatal testing. CONCLUSION: There is a significant relationship between lower SES, later prenatal diagnosis of trisomy, and higher live birth rate of T21 in Victoria.


Assuntos
Diagnóstico Pré-Natal , Trissomia/diagnóstico , Adulto , Diagnóstico Precoce , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Classe Social , Vitória
7.
Indian J Microbiol ; 59(1): 90-95, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30728635

RESUMO

Human gut microbiome studies are increasing at a rapid pace to understand contributions of the prokaryotic life to the innate workings of their eukaryotic host. Majority of studies focus on the pattern of gut microbial diversity in various diseases, however, understanding the core microbiota of healthy individuals presents a unique opportunity to study the microbial fingerprint in population specific studies. Present study was undertaken to determine the core microbiome of a healthy population and its imputed metabolic role. A total of 8990, clone library sequences (> 900 bp) of 16S rRNA gene from fecal samples of 43 individuals were used. The core gut microbiota was computed using QIIME pipeline. Our results show the distinctive predominance of genus Prevotella and the core composition of genera Prevotella, Bacteroides, Roseburia and Megasphaera in the Indian gut. PICRUSt analysis for functional imputation of the microbiome indicates a higher potential of the microbiota for carbohydrate metabolism. The presence of core microbiota may indicate key functions played by these microbes for the human host.

8.
J Biol Chem ; 291(10): 5049-67, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26742843

RESUMO

The α7 nicotinic acetylcholine receptors (nAChRs) are uniquely sensitive to selective positive allosteric modulators (PAMs), which increase the efficiency of channel activation to a level greater than that of other nAChRs. Although PAMs must work in concert with "orthosteric" agonists, compounds such as GAT107 ((3aR,4S,9bS)-4-(4-bromophenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonamide) have the combined properties of agonists and PAMs (ago-PAM) and produce very effective channel activation (direct allosteric activation (DAA)) by operating at two distinct sites in the absence of added agonist. One site is likely to be the same transmembrane site where PAMs like PNU-120596 function. We show that the other site, required for direct activation, is likely to be solvent-accessible at the extracellular domain vestibule. We identify key attributes of molecules in this family that are able to act at the DAA site through variation at the aryl ring substituent of the tetrahydroquinoline ring system and with two different classes of competitive antagonists of DAA. Analyses of molecular features of effective allosteric agonists allow us to propose a binding model for the DAA site, featuring a largely non-polar pocket accessed from the extracellular vestibule with an important role for Asp-101. This hypothesis is supported with data from site-directed mutants. Future refinement of the model and the characterization of specific GAT107 analogs will allow us to define critical structural elements that can be mapped onto the receptor surface for an improved understanding of this novel way to target α7 nAChR therapeutically.


Assuntos
Sítio Alostérico , Agonistas Nicotínicos/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/química , Regulação Alostérica , Sequência de Aminoácidos , Animais , Humanos , Isoxazóis/farmacologia , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Agonistas Nicotínicos/síntese química , Agonistas Nicotínicos/química , Compostos de Fenilureia/farmacologia , Quinolinas/farmacologia , Sulfonamidas/farmacologia , Xenopus , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
9.
Hum Mol Genet ; 24(10): 2733-45, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25634561

RESUMO

Delineating the genetic causes of developmental disorders is an area of active investigation. Mosaic structural abnormalities, defined as copy number or loss of heterozygosity events that are large and present in only a subset of cells, have been detected in 0.2-1.0% of children ascertained for clinical genetic testing. However, the frequency among healthy children in the community is not well characterized, which, if known, could inform better interpretation of the pathogenic burden of this mutational category in children with developmental disorders. In a case-control analysis, we compared the rate of large-scale mosaicism between 1303 children with developmental disorders and 5094 children lacking developmental disorders, using an analytical pipeline we developed, and identified a substantial enrichment in cases (odds ratio = 39.4, P-value 1.073e - 6). A meta-analysis that included frequency estimates among an additional 7000 children with congenital diseases yielded an even stronger statistical enrichment (P-value 1.784e - 11). In addition, to maximize the detection of low-clonality events in probands, we applied a trio-based mosaic detection algorithm, which detected two additional events in probands, including an individual with genome-wide suspected chimerism. In total, we detected 12 structural mosaic abnormalities among 1303 children (0.9%). Given the burden of mosaicism detected in cases, we suspected that many of the events detected in probands were pathogenic. Scrutiny of the genotypic-phenotypic relationship of each detected variant assessed that the majority of events are very likely pathogenic. This work quantifies the burden of structural mosaicism as a cause of developmental disorders.


Assuntos
Deficiências do Desenvolvimento/genética , Variação Estrutural do Genoma , Perda de Heterozigosidade , Mosaicismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Testes Genéticos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Am J Gastroenterol ; 112(5): 716-721, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27958287

RESUMO

OBJECTIVES: Current international guidelines for ocular radiation exposure suggest a threshold of 20 millisieverts (mSv)/year. Although endoscopists wear lead aprons, use of protective eye wear is optional. This study was conducted to analyze the lens radiation exposure during endoscopic retrograde cholangiopancreatography (ERCP) for endoscopists to determine the time of fluoroscopy needed to warrant using lens protection during ERCP. METHODS: ERCP patients were prospectively enrolled. Indications, interventions, fluoroscopy time, dose, and attending ± fellow involvement were recorded. Radiation exposure was collected from body dosimeters and dosimeters placed between the eyes. Cumulative radiation doses were obtained at study completion and averaged over the total fluoroscopy time to determine the mSv/hour exposure. RESULTS: A total of 187 cases were included. Attendings and fellows wore lens dosimeters in 178 and 126 cases, respectively, and body dosimeters in 174 and 128 cases, respectively. Attendings and fellows wore lens dosimeters throughout 15.89 and 11.24 h of fluoroscopy, respectively. The cumulative radiation dose absorbed per lens dosimeters was 5.35 mSv for attendings and 2.55 mSv for fellows. The projected lens absorption by the body dosimeters was 19.03 mSv for attendings and 5.21 mSv for fellows. The hourly fluoroscopy lens exposure was 0.34 mSv/hour for attendings and 0.23 mSv/hour for fellows. CONCLUSIONS: The amount of fluoroscopy hours needed to reach the currently suggested lens threshold limit (20 mSv/year) was 59.41 h for attendings and 88.17 h for fellows. Radioprotective eye wear should be worn by physicians with yearly fluoroscopy times in similarly structured practices that meet or exceed these thresholds.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Fluoroscopia , Gastroenterologia , Cristalino , Exposição Ocupacional , Doses de Radiação , Idoso , Dispositivos de Proteção dos Olhos , Bolsas de Estudo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/prevenção & controle , Estudos Prospectivos , Monitoramento de Radiação , Níveis Máximos Permitidos , Fatores de Tempo
11.
J Org Chem ; 82(2): 992-999, 2017 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-27966953

RESUMO

We report a facile, microwave-accelerated, one-pot tandem synthesis of unsymmetrical ureas via a Curtius rearrangement. In this method, one-pot microwave irradiation of commercially available (hetero)aromatic acids and amines in the presence of diphenylphosphoryl azide enabled extremely rapid (1-5 min) construction of an array of unsymmetrical ureas in good to excellent yields. We demonstrate the utility of our method in the efficient, gram-scale synthesis of key biologically active compounds targeting the cannabinoid 1 and α7 nicotinic acetylcholine receptors.


Assuntos
Química Orgânica/métodos , Micro-Ondas , Ureia , Azidas/química , Estrutura Molecular , Ureia/análogos & derivados , Ureia/síntese química , Ureia/química
12.
Gynecol Endocrinol ; 33(10): 801-806, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28454499

RESUMO

This observational study compares the ratio of serum anti-Mullerian hormone (AMH) to the total antral follicle count (AFC) (as a marker of AMH production per follicle) in the various phenotypes of women with polycystic ovary syndrome (PCOS) and isolated polycystic ovarian morphology (PCOM). Two hundred and sixty-two women were recruited. Women with PCOS were divided into four phenotypes based on the diagnostic inclusion criteria of oligo-anovulation (OA), hyperandrogenism (HA) and polycystic ovarian morphology (PCOM). These included Group A (OA + HA + PCOM), Group B (OA + HA), Group C (HA + PCOM) and Group D (OA + PCOM). A ratio of serum AMH to total AFC was calculated and expressed as the AMH/AFC ratio which was compared in the phenotypes of PCOS and isolated PCOM. The median AMH/AFC ratios in PCOS-A, PCOS-D, PCOS-C and PCOM were 1.5, 1.6, 1.2 and 1.1, respectively. There were significant differences in the groups compared [F(3, 238) = 6.14, p = 0.000)]. The ratios were significantly higher in the oligo-anovulatory phenotypes PCOS-A and PCOS-D than the PCOM (p = 0.004 and 0.002, respectively). There was no significant difference in the ratio between ovulatory phenotype PCOS-C and PCOM (p = 0.59). The role of androgens and LH in per-follicle AMH production remains limited. The findings support the hypothesis of a key role for AMH in the mechanism of anovulation in PCOS.


Assuntos
Hormônio Antimülleriano/sangue , Cistos Ovarianos/metabolismo , Folículo Ovariano/patologia , Síndrome do Ovário Policístico/metabolismo , Adulto , Anovulação/etiologia , Anovulação/metabolismo , Anovulação/patologia , Hormônio Antimülleriano/metabolismo , Variação Biológica da População , Contagem de Células , Estudos Transversais , Feminino , Humanos , Cistos Ovarianos/complicações , Cistos Ovarianos/patologia , Folículo Ovariano/metabolismo , Reserva Ovariana , Fenótipo , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/patologia
13.
Pharm Res ; 33(7): 1587-601, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26951567

RESUMO

PURPOSE: To develop a multifunctional nanoparticle system carrying a combination of pro-apoptotic drug, NCL-240, TRAIL [tumor necrosis factor-α (TNF-α)-related apoptosis-inducing ligand] and anti-survivin siRNA and to test the combination preparation for anti-cancer effects in different cancer cells. METHODS: Polyethylene glycol-phosphoethanolamine (PEG-PE) - based polymeric micelles were prepared carrying NCL-240. These micelles were used in combination with TRAIL-conjugated micelles and anti-survivin siRNA-S-S-PE containing micelles. All the micelles were characterized for size, zeta potential, and drug encapsulation efficiency. Different cancer cells were used to study the cytotoxicity potential of the individual as well as the combination formulations. Other cell based assays included cellular association studies of transferrin-targeted NCL-240 micelles and study of cellular survivin protein downregulation by anti-survivin siRNA-S-S-PE containing micelles. RESULTS: NCL-240 micelles and the combination NCL-240/TRAIL micelles significantly increased cytotoxicity in the resistant strains of SKOV-3, MCF-7 and A549 as compared to free drugs or single drug formulations. The NCL-240/TRAIL micelles were also more effective in NCI/ADR-RES cancer cell spheroids. Anti-survivin siRNA micelles alone displayed a dose-dependent reduction in survivin protein levels in A2780 cells. Treatment with NCL-240/TRAIL after pre-incubation with anti-survivin siRNA inhibited cancer cell proliferation. Additionally, a single multifunctional system composed of NCL-240/TRAIL/siRNA PM also had significant cytotoxic effects in vitro in multiple cell lines. CONCLUSION: These results demonstrate the efficacy of a combination of small-molecule PI3K inhibitors, TRAIL, and siRNA delivered by micellar preparations in multiple cancer cell lines.


Assuntos
Apoptose/efeitos dos fármacos , Clorofenóis/farmacologia , Nanopartículas/química , RNA Interferente Pequeno/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Triazóis/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Química Farmacêutica/métodos , Clorofenóis/química , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Células MCF-7 , Camundongos , Micelas , Células NIH 3T3 , Nanopartículas/administração & dosagem , Tamanho da Partícula , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , RNA Interferente Pequeno/química , Survivina , Ligante Indutor de Apoptose Relacionado a TNF/química , Triazóis/química
14.
Pharm Res ; 33(10): 2540-51, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27351426

RESUMO

PURPOSE: To develop transferrin (Tf)-targeted delivery systems for the pro-apoptotic drug, NCL-240, and to evaluate the efficacy of this delivery system in ovarian cancer NCI/ADR-RES cells, grown in vitro in a 3D spheroid model. METHODS: Tf-targeted PEG-PE-based micellar and ePC/CHOL-based liposomal delivery systems for NCL-240 were prepared. NCI/ADR-RES cells were used to generate spheroids by a non-adhesive liquid overlay technique. Spheroid growth and development were monitored by size (diameter) analysis and H&E staining. The targeted formulations were compared to untargeted ones in terms of their degree of spheroid association and penetration. A cell viability analysis with NCL-240-loaded micelles and liposomes was performed to assess the effectiveness of Tf-targeting. RESULTS: Tf-targeted polymeric micelles and Tf-targeted liposomes loaded with NCL-240 were prepared. NCI/ADR-RES cells generated spheroids that demonstrated the presence of a distinct necrotic core along with proliferating cells in the spheroid periphery, partly mimicking in vivo tumors. The Tf-targeted micelles and liposomes had a deeper spheroid penetration as compared to the untargeted delivery systems. Cell viability studies using the spheroid model demonstrated that Tf-mediated targeting markedly improved the cytotoxicity profile of NCL-240. CONCLUSION: Transferrin targeting enhanced delivery and effectiveness of micelles and liposomes loaded with NCL-240 against NCI/ADR-RES cancer cells in a 3D spheroid model.


Assuntos
Apoptose/efeitos dos fármacos , Clorofenóis/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Micelas , Neoplasias Ovarianas , Pró-Fármacos/administração & dosagem , Triazóis/administração & dosagem , Apoptose/fisiologia , Linhagem Celular Tumoral , Clorofenóis/metabolismo , Feminino , Humanos , Lipossomos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Pró-Fármacos/metabolismo , Transferrina/administração & dosagem , Transferrina/metabolismo , Triazóis/metabolismo , Células Tumorais Cultivadas
15.
Surg Endosc ; 30(1): 233-44, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25847137

RESUMO

BACKGROUND: Peroral endoscopic myotomy (POEM) has been performed as a novel endoscopic procedure to treat achalasia with favorable outcome. The objective of this study was to assess the outcome of POEM in our initial series and to assess the safety and efficacy of POEM in a variety of esophageal motility-related clinical problems. METHODS: This is a retrospective cross-sectional study involving all patients with esophageal motility disorders defined by the Chicago classification, who had undergone consideration for POEM at our institution. Validated questionnaires such as gastroesophageal reflux disease health-related quality of life (GERD-HRQL), reflux symptom index (RSI) and achalasia disease-specific health-related quality of life were obtained pre- and postoperatively. RESULTS: From January 2013 to October 2014, a total of 35 POEMs (achalasia n = 25, non-achalasia n = 10) were performed on 33 patients (female n = 20, male n = 13, mean age 56.9 years). There was no mortality. The rate of inadvertent mucosotomy was 17.1%. The rate of complications requiring interventions was 5.7%. During a mean follow-up period of 7 months (range 0.5-17), 92% of patients with achalasia and 75% of those with non-achalasia motility disorders had a symptomatic improvement in dysphagia. Chest pain was completely resolved in all patients with achalasia (8/8) and 80% of patients with non-achalasia (4/5). The GERD-HRQL, RSI and dysphagia scores significantly improved after POEM in patients with achalasia. There was a significant improvement in GERD-HRQL and RSI scores, and a trend toward lower dysphagia score in patients with non-achalasia. CONCLUSIONS: The outcome of POEM to treat achalasia and non-achalasia motility disorders is consistent with previous studies. Potential benefit of POEM includes not only its flexibility to adjust the length and location of myotomy but also the ability to extend myotomy proximally without thoracoscopy or thoracotomy. POEM can be combined with laparoscopic procedures and used as "salvage" for localized esophageal dysmotility.


Assuntos
Acalasia Esofágica/cirurgia , Esofagoscopia , Mucosa/cirurgia , Cirurgia Endoscópica por Orifício Natural , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
16.
J Biol Chem ; 289(7): 4515-31, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24362025

RESUMO

GAT107, the (+)-enantiomer of racemic 4-(4-bromophenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonamide, is a strong positive allosteric modulator (PAM) of α7 nicotinic acetylcholine receptor (nAChR) activation by orthosteric agonists with intrinsic allosteric agonist activities. The direct activation produced by GAT107 in electrophysiological studies is observed only as long as GAT107 is freely diffusible in solution, although the potentiating activity primed by GAT107 can persist for over 30 min after drug washout. Direct activation is sensitive to α7 nAChR antagonist methyllycaconitine, although the primed potentiation is not. The data are consistent with GAT107 activity arising from two different sites. We show that the coupling between PAMs and the binding of orthosteric ligands requires tryptophan 55 (Trp-55), which is located at the subunit interface on the complementary surface of the orthosteric binding site. Mutations of Trp-55 increase the direct activation produced by GAT107 and reduce or prevent the synergy between allosteric and orthosteric binding sites, so that these mutants can also be directly activated by other PAMs such as PNU-120596 and TQS, which do not activate wild-type α7 in the absence of orthosteric agonists. We identify Tyr-93 as an essential element for orthosteric activation, because Y93C mutants are insensitive to orthosteric agonists but respond to GAT107. Our data show that both orthosteric and allosteric activation of α7 nAChR require cooperative activity at the interface between the subunits in the extracellular domain. These cooperative effects rely on key aromatic residues, and although mutations of Trp-55 reduce the restraints placed on the requirement for orthosteric agonists, Tyr-93 can conduct both orthosteric activation and desensitization among the subunits.


Assuntos
Ativadores de Enzimas/farmacologia , Quinolinas/farmacologia , Sulfonamidas/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Regulação Alostérica/efeitos dos fármacos , Substituição de Aminoácidos , Aminoácidos Aromáticos/química , Aminoácidos Aromáticos/genética , Aminoácidos Aromáticos/metabolismo , Animais , Ativação Enzimática/efeitos dos fármacos , Ativadores de Enzimas/química , Feminino , Humanos , Mutação de Sentido Incorreto , Estrutura Terciária de Proteína , Quinolinas/química , Sulfonamidas/química , Xenopus laevis , Receptor Nicotínico de Acetilcolina alfa7/química , Receptor Nicotínico de Acetilcolina alfa7/genética
17.
Gastroenterology ; 147(3): 646-654.e2, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24906040

RESUMO

BACKGROUND & AIMS: Administration of secretin improves noninvasive imaging of the pancreatic duct with magnetic resonance cholangiopancreatography (MRCP). We performed a large prospective study to investigate whether synthetic human secretin (RG1068)-stimulated MRCP detects pancreatic duct abnormalities with higher levels of sensitivity than MRCP. METHODS: We performed a phase 3, multicenter, baseline-controlled study of patients with acute or acute recurrent pancreatitis who were scheduled to undergo endoscopic retrograde cholangiopancreatography (ERCP) between March 26, 2008, and October 28, 2009. Patients underwent a baseline MRCP that was immediately followed by administration of RG1068 and repeat MRCP and then underwent ERCP within 30 days; they were followed up for 30 days. MRCP and ERCP images were read centrally by 3 radiologists and 2 endoscopists, respectively, who were all independent and blinded; pancreatic duct abnormalities were evaluated. The accuracy of MRCP was evaluated using ERCP as the standard. RESULTS: In total, 258 patients were enrolled in the study; 251 MRCP image sets were assessed, and 236 patients had evaluable ERCPs. Pancreatic duct abnormalities were observed in 60.2% of ERCP images. All radiologists identified duct abnormalities in RG1068-ciné MRCP image sets with significantly higher levels of sensitivity (P < .0001) than in images from MRCP, with minimal loss of specificity. Adverse events were reported in 38.0% of patients after MRCP and 68.1% after ERCP. Of the 55 patients who experienced a serious adverse event, 3 (1.2%) and 52 (20.5%) of the events were reported to be temporally associated with MRCP and ERCP, respectively. The adverse events most frequently considered related to RG1068 were nausea, abdominal pain, and flushing; most were mild. CONCLUSIONS: Compared with images from MRCP, those from RG1068-stimulated MRCP are improved in many aspects and could aid in diagnosis and clinical decision making for patients with acute, acute recurrent, or chronic pancreatitis. RG1068-enhanced MRCP might also better identify patients in need of therapeutic ERCP (ClinicalTrials.gov, Number: NCT00660335).


Assuntos
Colangiopancreatografia por Ressonância Magnética , Ductos Pancreáticos/patologia , Pancreatite/diagnóstico , Secretina , Doença Aguda , Adulto , Canadá , Colangiopancreatografia Retrógrada Endoscópica , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Pancreatite/patologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Recidiva , Secretina/administração & dosagem , Estados Unidos
18.
Fetal Diagn Ther ; 38(4): 254-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25925597

RESUMO

OBJECTIVES: The aim was to investigate aneuploidy detection using an approach based on nuchal translucency (NT) and non-invasive prenatal testing (NIPT). METHODS: This was a cohort study including 5,306 high-risk pregnancies with NT measurements and chorionic villus samples (CVS) tested for full karyotype. RESULTS: The fetal karyotype was normal in 4,172 (78.6%) cases and abnormal in 1,134 (21.4%), including 1,009 with a likely clinically significant adverse outcome. Universal CVS with full karyotyping would lead to the diagnosis of all clinically significant abnormalities. A policy of relying solely on NIPT would have led to the diagnosis of 88.9% of clinically significant abnormalities. A strategy whereby NIPT is the main method, with CVS reserved for cases with NT ≥3.0 mm, would require CVS in 21.7% of cases, identify 94.8% of significant abnormalities and avoid miscarriage in 41 pregnancies compared to CVS for all. CONCLUSIONS: A policy of NIPT for increased-risk cases and CVS with full karyotype if the NT was ≥3.0 mm reduced the risk of miscarriage yet still identified 95% of clinically significant aneuploidy.


Assuntos
Aneuploidia , Transtornos Cromossômicos/diagnóstico , Medição da Translucência Nucal , Diagnóstico Pré-Natal/métodos , Amostra da Vilosidade Coriônica , Feminino , Humanos , Cariotipagem , Gravidez , Resultado da Gravidez , Gravidez de Alto Risco , Estudos Retrospectivos , Medição de Risco
19.
Neuropharmacology ; 257: 110052, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936657

RESUMO

The direct blockade of CB1 cannabinoid receptors produces therapeutic effects as well as adverse side-effects that limit their clinical potential. CB1 negative allosteric modulators (NAMs) represent an indirect approach to decrease the affinity and/or efficacy of orthosteric cannabinoid ligands or endocannabinoids at CB1. We recently reported that GAT358, a CB1-NAM, blocked opioid-induced mesocorticolimbic dopamine release and reward via a CB1-allosteric mechanism of action. Whether a CB1-NAM dampens opioid-mediated therapeutic effects such as analgesia or alters other unwanted opioid side-effects remain unknown. Here, we characterized the effects of GAT358 on nociceptive behaviors in the presence and absence of morphine in male rats. We examined the impact of GAT358 on formalin-evoked pain behavior and Fos protein expression, a marker of neuronal activation, in the lumbar spinal cord. We also assessed the impact of GAT358 on morphine-induced slowing of colonic transit, tolerance, and withdrawal behaviors in male mice. GAT358 attenuated morphine antinociceptive tolerance without blocking acute antinociception and reduced morphine-induced slowing of colonic motility without impacting fecal boli production. GAT358 also produced antinociception in the presence and absence of morphine in the formalin model of inflammatory nociception and reduced the number of formalin-evoked Fos protein-like immunoreactive cells in the lumbar spinal cord. Finally, GAT358 mitigated the somatic signs of naloxone-precipitated, but not spontaneous, opioid withdrawal following chronic morphine dosing. Our results support the therapeutic potential of CB1-NAMs as novel drug candidates aimed at preserving opioid-mediated analgesia while preventing their unwanted side-effects. Our studies also uncover previously unrecognized antinociceptive properties associated with an arrestin-biased CB1-NAM.

20.
bioRxiv ; 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38260598

RESUMO

The direct blockade of CB 1 cannabinoid receptors produces therapeutic effects as well as adverse side-effects that limit their clinical potential. CB 1 negative allosteric modulators (NAMs) represent an indirect approach to decrease the affinity and/or efficacy of orthosteric cannabinoid ligands or endocannabinoids at CB 1 . We recently reported that GAT358, a CB 1 -NAM, blocked opioid-induced mesocorticolimbic dopamine release and reward via a CB 1 -allosteric mechanism of action. Whether a CB 1 -NAM dampens opioid-mediated therapeutic effects such as analgesia or alters other unwanted side-effects of opioids remain unknown. Here, we characterized the effects of GAT358 on nociceptive behaviors in the presence and absence of morphine. We examined the impact of GAT358 on formalin-evoked pain behavior and Fos protein expression, a marker of neuronal activation, in the lumbar dorsal horn. We also assessed the impact of GAT358 on morphine-induced slowing of colonic transit, tolerance, and withdrawal behaviors. GAT358 attenuated morphine antinociceptive tolerance without blocking acute antinociception. GAT358 also reduced morphine-induced slowing of colonic motility without impacting fecal boli production. GAT358 produced antinociception in the presence and absence of morphine in the formalin model of inflammatory nociception and reduced the number of formalin-evoked Fos protein-like immunoreactive cells in the lumbar spinal dorsal horn. Finally, GAT358 mitigated the somatic signs of naloxone-precipitated, but not spontaneous, opioid withdrawal following chronic morphine dosing in mice. Our results support the therapeutic potential of CB 1 -NAMs as novel drug candidates aimed at preserving opioid-mediated analgesia while preventing their unwanted side-effects. Our studies also uncover previously unrecognized antinociceptive properties associated with an arrestin-biased CB 1 -NAMs. Highlights: CB 1 negative allosteric modulator (NAM) GAT358 attenuated morphine tolerance GAT358 reduced morphine-induced slowing of colonic motility but not fecal productionGAT358 was antinociceptive for formalin pain alone and when combined with morphineGAT358 reduced formalin-evoked Fos protein expression in the lumbar spinal cordGAT358 mitigated naloxone precipitated withdrawal after chronic morphine dosing.

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