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1.
Inorg Chem ; 61(46): 18640-18652, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36350227

RESUMO

We report a comprehensive assessment of Lewis acidity for a series of carbone-stibenium and -bismuthenium ions using the Gutmann-Beckett (GB) method. These new antimony and bismuth cations have been synthesized by halide abstractions from (CDC)PnBr3 and [(pyCDC)PnBr2][Br] (CDC = carbodicarbene; Pn = Sb or Bi; py = pyridyl). The reaction of (CDC)SbBr3 (1) with one or two equivalents of AgNTf2 (NTf2 = bis(trifluoromethanesulfonyl)imide) or AgSbF6 gives stibaalkene mono- and dications of the form [(CDC)SbBr3-n][A]n (2-4; n = 1,2; A = NTf2 or SbF6). The stibaalkene trication [(CDC)2Sb][NTf2]3 (5) was also isolated and collectively these molecules fill the gap among the series of cationic pnictaalkenes. The Sb cations are compared to the related CDC-bismaalkene complexes 6-9. With the goal of preparing highly Lewis acidic compounds, a tridentate bis(pyridine)carbodicarbene (pyCDC) was used as a ligand to access [(pyCDC)PnBr2][Br] (10, 12) and trications [(pyCDC)Pn][NTf2]3 (Pn = Sb (11), Bi (13)), forgoing the need for a second CDC as used in the synthesis of 5. The bonding situation in these complexes is elucidated through electron density and energy decomposition analyses in combination with natural orbital for chemical valence theory. In each complex, there exists a CDC-Pn double bonding interaction, consisting of a strong σ-bond and a weaker π-bond, whereby the π-bond gradually strengthens with the increase in cationic charge in the complex. Notably, [(CDC)SbBr][NTf2]2 (4) has an acceptor number (AN) (84) that is comparable to quintessential Lewis acids such as BF3, and tricationic pnictaalkene complexes 11 and 13 exhibit strong Lewis acidity with ANs of 109 (Pn = Sb) and 84 (Pn = Bi), respectively, which are among the highest values reported for any antimony or bismuth cation. Moreover, the calculated fluoride ion affinities (FIAs) for 11 and 13 are 99.8 and 94.3 kcal/mol, respectively, which are larger than that of SbF5 (85.1 kcal/mol), which suggest that these cations are Lewis superacids.

2.
J Low Genit Tract Dis ; 22(3): 184-188, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29733302

RESUMO

OBJECTIVE: The aim of the study was to estimate the excess cost of guideline nonadherent cervical cancer screening in women beyond the recommended screening ages or posthysterectomy in a single healthcare system. MATERIALS AND METHODS: All Pap tests performed between September 1, 2012, and August 31, 2014, in women younger than 21 years, older than 65 years, or after hysterectomy, were coded as guideline adherent or nonadherent per the 2012 America Society of Colposcopy and Clinical Pathology guidelines. We assumed management of abnormal results per the 2013 America Society of Colposcopy and Clinical Pathology management guidelines. Costs were obtained from a literature review and Center for Medicare and Medicaid Services data and applied to nonadherent screening and subsequent diagnostic tests. RESULTS: During this period, 1,398 guideline nonadherent Pap tests were performed (257 in women <21 years, 536 in women >65 years, and 605 after hysterectomy), with 88 abnormal results: 35 (13.5%) in women younger than 21 years, 14 (2.6%) in women older than 65 years, and 39 (6.5%) in women after hysterectomy. The excess cost for initial screening, diagnostic tests, and follow-up was US $35,337 for 2 years in women younger than 21 years, US $54,378 for 5 years in women older than 65 years, and US $77,340 for 5 years in women after hysterectomy, resulting in a total excess cost of US $166,100 for 5 years. Of the 1,398 women who underwent guideline nonadherent screening, there were only 2 (0.1%) diagnoses of high-grade dysplasia (VaIN3). CONCLUSIONS: Guideline nonadherent cervical cancer screening in women beyond the recommended screening ages and posthysterectomy resulted in costs exceeding US $160,000 for screening, diagnostic tests, and follow-up with minimal improvement in detection of high-grade dysplasia.


Assuntos
Programas de Rastreamento/economia , Neoplasias do Colo do Útero/diagnóstico , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Histerectomia , Pessoa de Meia-Idade , Teste de Papanicolaou , Neoplasias do Colo do Útero/cirurgia , Adulto Jovem
3.
J Low Genit Tract Dis ; 16(3): 175-204, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22418039

RESUMO

An update to the American Cancer Society (ACS) guideline regarding screening for the early detection of cervical precancerous lesions and cancer is presented. The guidelines are based on a systematic evidence review, contributions from six working groups, and a recent symposium co-sponsored by the ACS, American Society for Colposcopy and Cervical Pathology (ASCCP), and American Society for Clinical Pathology (ASCP), which was attended by 25 organizations. The new screening recommendations address age-appropriate screening strategies, including the use of cytology and high-risk human papillomavirus (HPV) testing, follow-up (e.g., management of screen positives and screening interval for screen negatives) of women after screening, age at which to exit screening, future considerations regarding HPV testing alone as a primary screening approach, and screening strategies for women vaccinated against HPV16/18 infections.


Assuntos
Colposcopia/métodos , Detecção Precoce de Câncer/normas , Guias de Prática Clínica como Assunto , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/prevenção & controle , Adulto , Fatores Etários , Idoso , American Cancer Society , Biópsia por Agulha , Citodiagnóstico/normas , Medicina Baseada em Evidências , Feminino , Humanos , Imuno-Histoquímica , Programas de Rastreamento/normas , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Gestão de Riscos , Sociedades Médicas/normas , Estados Unidos , Adulto Jovem , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/patologia
4.
Chem Biol ; 17(1): 38-45, 2010 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-20142039

RESUMO

Several approaches have been developed for screening combinatorial libraries or collections of synthetic molecules for agonists or antagonists of protein function, each with its own advantages and limitations. In this report, we describe an experimental platform that seamlessly couples massively parallel bead-based screening of one-bead one-compound combinatorial libraries with microarray-based quantitative comparisons of the binding affinities of the many hits isolated from the bead library. Combined with other technical improvements, this technique allows the rapid identification of the best protein ligands in combinatorial libraries containing millions of compounds without the need for labor-intensive resynthesis of the hits.


Assuntos
Técnicas de Química Combinatória/métodos , Biblioteca de Peptídeos , Análise Serial de Proteínas , Proteínas/metabolismo , Técnicas de Química Combinatória/economia , Ligantes , Magnetismo , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica , Proteínas/química , Fatores de Tempo
5.
Gynecol Oncol ; 109(2 Suppl): S22-30, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18482555

RESUMO

Significant disparities in cervical cancer incidence and mortality rates among minority groups have been documented in the United States, despite an overall decline in these rates for the population as a whole. Differences in cervical cancer screening practices have been suggested as an explanation for these disparities, as have differences in treatment among various racial and ethnic groups. A number of factors are attributed to these observed differences. As minority populations continue to grow in size over the next 50 years, persistent disparities will place an ever increasing burden on these populations and on the national healthcare system. Strategies to reduce cervical cancer disparities need to be employed in order to reverse these trends.


Assuntos
Etnicidade , Disparidades nos Níveis de Saúde , Neoplasias do Colo do Útero/etnologia , Neoplasias do Colo do Útero/epidemiologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Fatores Socioeconômicos , Estados Unidos/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle
7.
Ann N Y Acad Sci ; 847: 103-17, 1998 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-9668703

RESUMO

The aims of this study are (1) to evaluate the efficiency of ultrasound in detecting CA in low-risk populations of pregnant women by routine screening performed in hospital ultrasound labs (level II); (2) to highlight the areas where improvement could be obtained; (3) to determine efficient timing and number of examinations; (4) to evaluate the psychological returns of detection and nondetection of CA; and (5) to evaluate the cost-effectiveness ratio of antenatal screening of CA. A European collaboration was supposed to help in meeting these objectives because results concerning the analysis of individual CAs or groups of CAs can only be statistically significant when their number is sufficiently large. It was estimated that it was necessary to collect nearly 5,000 CA; this corresponds to about 200,000 pregnant women, the prevalence of malformations at birth being estimated at 2.5%. These conditions yield worthy conclusions, given the following circumstances: a large variety of CA, the extremely low incidence of each CA, the multiple approaches for diagnosis and management, the manifold classes of defects, the differences in gestational age when anomalies are detectable and detected. We study prospectively (1) the reliability of ultrasound in detecting antenatal malformations by recording all CA, ultrasonically suspected and not; (2) the gestational age of anomaly recognition; (3) the response to antenatal diagnosis of CA; (4) the individual outcome of pregnancies; (5) the financial cost of the screening program; and (6) the psychological consequences for the parents.


Assuntos
Anormalidades Congênitas/diagnóstico por imagem , Testes Diagnósticos de Rotina , Feto/anormalidades , Ultrassonografia Pré-Natal , Anormalidades Congênitas/economia , Testes Diagnósticos de Rotina/economia , Testes Diagnósticos de Rotina/métodos , Diretórios como Assunto , Europa (Continente) , Estudos de Avaliação como Assunto , Feminino , Idade Gestacional , Humanos , Laboratórios Hospitalares , Gravidez , Terminologia como Assunto , Ultrassonografia Pré-Natal/economia , Ultrassonografia Pré-Natal/métodos
8.
Ann N Y Acad Sci ; 847: 125-35, 1998 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-9668705

RESUMO

In this paper, we show that the ratio of the number of fetal anomalies detected by ultrasounds (US) to the total number of cases is not a consistent estimator of the US sensitivity. As Eddy pointed out, when the disease evolves over time, the sensitivity of a test also varies over time according to the development of the disease. To assess correctly the detection capability of a test, it is therefore necessary to estimate a time continuous function (sensitivity function) instead of a single parameter. From a methodological point of view, by considering the "detectability" time of a fetal anomaly as a random variable and parametrizing its distribution function, we estimate the probability that an anomaly is detected conditional upon the precise timing of actually performed US during pregnancy. We fit this model with Eurofetus data (about 7,300 abnormal fetuses), and we compare estimations for different kinds of anomalies (classification based on the system involved and/or severity of the handicap). To allow for heterogeneity of anomalies regarding the detectability time, we generally adopt mixture models. For instance, we select a bi-gamma distribution for major malformations and estimate that 63% of such anomalies are detectable quite early in pregnancy (conditional mean: 15.2 weeks of amenorrhea (WA) +/- 4.2 WA), the others becoming detectable later (30.3 WA +/- 6.4 WA). Such results are then integrated in a cost-effectiveness analysis.


Assuntos
Feto/anormalidades , Ultrassonografia Pré-Natal , Anormalidades Congênitas/diagnóstico por imagem , Anormalidades Congênitas/economia , Análise Custo-Benefício , Bases de Dados Factuais , Europa (Continente) , Feminino , Humanos , Modelos Estatísticos , Método de Monte Carlo , Gravidez , Sensibilidade e Especificidade , Fatores de Tempo , Ultrassonografia Pré-Natal/economia , Ultrassonografia Pré-Natal/estatística & dados numéricos
10.
J Clin Ultrasound ; 4(1): 3-5, 1976 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-814138

RESUMO

The ultrasonic examination of 6,690 pregnant patients showed a greater number of multiple pregnancies than usually observed at delivery: 71 per cent of twin gestations diagnosed before 10 weeks were singletons when delivered.


Assuntos
Gravidez Múltipla , Ultrassonografia , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Gêmeos
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