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1.
J Am Chem Soc ; 146(22): 15376-15392, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38771156

RESUMO

Couplings between vibrational motions are driven by electronic interactions, and these couplings carry special significance in vibrational energy transfer, multidimensional spectroscopy experiments, and simulations of vibrational spectra. In this investigation, the many-body contributions to these couplings are analyzed computationally in the context of clathrate-like alkali metal cation hydrates, including Cs+(H2O)20, Rb+(H2O)20, and K+(H2O)20, using both analytic and quantum-chemistry potential energy surfaces. Although the harmonic spectra and one-dimensional anharmonic spectra depend strongly on these many-body interactions, the mode-pair couplings were, perhaps surprisingly, found to be dominated by one-body effects, even in cases of couplings to low-frequency modes that involved the motion of multiple water molecules. The origin of this effect was traced mainly to geometric distortion within water monomers and cancellation of many-body effects in differential couplings, and the effect was also shown to be agnostic to the identity of the ion. These outcomes provide new understanding of vibrational couplings and suggest the possibility of improved computational methods for the simulation of infrared and Raman spectra.

2.
BMC Med Educ ; 24(1): 252, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459487

RESUMO

BACKGROUND: In the United States, Obstetrics and Gynecology residency interviews are instrumental in assessing the compatibility between medical student applicants and residency programs during the match process. Applicant perceptions of Obstetrics and Gynecology residency culture are a key component in determining how they rank residency programs. In 2020, residency interviews transitioned to a virtual format, and little is known about how applicants evaluated program culture during this first round of universal virtual interviews. Medical students in the United States commonly use Reddit, a popular social media platform, to discuss residency programs and share interview experiences. We explored Obstetrics and Gynecology applicants' considerations regarding residency program culture during the first universal virtual interview season in 2020-2021 by analyzing posts on a Google spreadsheet accessed through Reddit. METHODS: In 2022, we imported 731 posts from the "2020-21 OB GYN Residency Applicant Spreadsheet" Google spreadsheet posted to the 2020-2021 Residency Interview Spreadsheet megathread on the r/medicalschool subreddit to NVivo 12(QSR International, Burlington, MA), a qualitative analysis software program. Three investigators used qualitative inductive techniques to code and identify themes. RESULTS: Applicants used visual, verbal and behavioral cues during virtual Obstetrics and Gynecology residency interviews to understand three components of the workplace culture: prioritization of diversity, equity and inclusion, social environment, and resident workload. CONCLUSIONS: Obstetrics and Gynecology residency programs convey information about their culture during virtual interviews through the behavior, appearances and responses of residents and interviewers to applicant questions. To ensure they accurately represent their culture to applicants, programs should consider educating residents and faculty around the implications of interview-day conduct.


Assuntos
Ginecologia , Internato e Residência , Obstetrícia , Mídias Sociais , Estudantes de Medicina , Humanos , Estados Unidos , Ginecologia/educação , Obstetrícia/educação
3.
J Phys Chem A ; 127(32): 6647-6659, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37587877

RESUMO

The structures, vibrational spectra, and electronic properties of copper hydroxide hydrates CuOH+(H2O)3-7 were investigated with quantum chemistry computations. As a follow-up to a previous analysis of CuOH+(H2O)0-2, this investigation examined the progression as the square-planar metal coordination environment was filled and as solvation shells expanded. Four-, five-, and six-coordinate structures were found to be low-energy isomers. The delocalized radical character, which was discovered in the small clusters, was found to persist upon continued hydration, although the hydrogen-bonded water network in the larger clusters was found to play a more significant role in accommodating this spin. Partial charges indicated that the electronic structure includes more Cu2+···OH- character than was observed in smaller clusters, but this structure remains decidedly mixed with Cu+···OH· configurations and yields roughly half-oxidation of the water network in the absence of any electrochemical potential. Computed vibrational spectra for n = 3 showed congruence with spectra from recent predissociation spectroscopy experiments, provided that the role of the D2 tag was taken into account. Spectra for n = 4-7 were predicted to exhibit features that are reflective of both the mixed electronic character and proton-/hydrogen-shuttling motifs within the hydrogen-bonded water network.

4.
J Chem Phys ; 159(20)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38010326

RESUMO

Simulations of anharmonic vibrational motion rely on computationally expedient representations of the governing potential energy surface. The n-mode representation (n-MR)-effectively a many-body expansion in the space of molecular vibrations-is a general and efficient approach that is often used for this purpose in vibrational self-consistent field (VSCF) calculations and correlated analogues thereof. In the present analysis, a lack of convergence in many VSCF calculations is shown to originate from negative and unbound potentials at truncated orders of the n-MR expansion. For cases of strong anharmonic coupling between modes, the n-MR can both dip below the true global minimum of the potential surface and lead to effective single-mode potentials in VSCF that do not correspond to bound vibrational problems, even for bound total potentials. The present analysis serves mainly as a pathology report of this issue. Furthermore, this insight into the origin of VSCF non-convergence provides a simple, albeit ad hoc, route to correct the problem by "painting in" the full representation of groups of modes that exhibit these negative potentials at little additional computational cost. Somewhat surprisingly, this approach also reasonably approximates the results of the next-higher n-MR order and identifies groups of modes with particularly strong coupling. The method is shown to identify and correct problematic triples of modes-and restore SCF convergence-in two-mode representations of challenging test systems, including the water dimer and trimer, as well as protonated tropine.

5.
J Chem Phys ; 159(8)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37606324

RESUMO

The vibrational self-consistent field (VSCF) method yields anharmonic states and spectra for molecular vibrations, and it serves as the starting point for more sophisticated correlated-vibration methods. Convergence of the iterative, non-linear optimization in VSCF calculations can be erratic or altogether unsuccessful, particularly for chemical systems involving low-frequency motions. In this work, a vibrational formulation of the Direct Inversion of the Iterative Subspace method of Pulay is presented and investigated. This formulation accounts for distinct attributes of the vibrational and electronic cases, including the expansion of each single-mode vibrational wavefunction in its own basis set. The resulting Direct Inversion of the Iterative Subspace method is shown to substantially accelerate VSCF convergence in all convergent cases as well as rectify many cases where Roothaan-based methods fail. Performance across systems ranging from small, rigid molecules to weakly bound molecular clusters is investigated in this analysis.

6.
Cancer Causes Control ; 33(3): 455-461, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35040017

RESUMO

PURPOSE: Physical activity (pre- and post-diagnosis) has been studied in prevention and survivorship contexts for endometrial cancer. However, the association of physical activity (PA) across the lifespan on mortality risk among endometrial cancer survivors is understudied. The study's objective was to identify the association of lifetime PA on mortality risk in endometrial cancer survivors. METHODS: Seven hundred forty-five endometrial cancer survivors drawn from a population-based cancer registry (diagnosed between 1991 and 1994) reported the frequency (sessions/week) of moderate- and vigorous intensity physical activity (MVPA) at age 12, age 20, and 5 years pre-interview (post-diagnosis). Cox proportional hazards were used to estimate hazard ratios (HR) and 95% confidence intervals for the association between PA, all-cause, and cardiovascular disease mortality as assessed in 2016. MVPA was modeled using natural cubic splines. RESULTS: Diagnosis age, body mass index, and smoking (pack-years) were each positively associated with increased all-cause mortality risk. Those who did one session of MVPA 5 years pre-interview had a lower mortality risk (HR 0.61; 95% CI 0.41-0.92) compared to those with no MVPA. Those reporting one session of MVPA was similarly observed at age 12 (HR 0.95; 95% CI 0.86-1.06) and at age 20 (HR 0.87; 95% CI 0.65-1.16). CONCLUSION: Those who participated in PA, compared to those who did not, in the 5 years before diagnosis had a lower mortality risk. While PA was not independently protective against mortality risk at ages 12 or 20, PA is still important for endometrial cancer survivors for other non-mortality outcomes.


Assuntos
Sobreviventes de Câncer , Neoplasias do Endométrio , Adulto , Criança , Neoplasias do Endométrio/epidemiologia , Exercício Físico , Feminino , Humanos , Longevidade , Fatores de Risco , Sobreviventes , Adulto Jovem
7.
Support Care Cancer ; 30(1): 447-455, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34304292

RESUMO

PURPOSE: Endometrial cancer is strongly linked to obesity and inactivity; however, increased physical activity has important benefits even in the absence of weight loss. Resistance (strength) training can deliver these benefits; yet few women participate in resistance exercise. The purpose of this study was to describe both physiological and functional changes following a home-based strength training intervention. METHODS: Forty post-treatment endometrial cancer survivors within 5 years of diagnosis were enrolled in a pilot randomized trial, comparing twice-weekly home-based strength exercise to wait list control. Participants conducted the exercises twice per week for 10 supervised weeks with 5 weeks of follow-up. Measures included DXA-measured lean mass, functional fitness assessments, blood biomarkers, and quality of life outcomes. RESULTS: On average, participants were 60.9 years old (SD = 8.7) with BMI of 39.9 kg/m2 (SD = 15.2). At baseline, participants had 51.2% (SD = 6.0) body fat, which was not different between groups. Improvements were seen in the 30-s chair sit to stand (d = .99), the 30-s arm curl (d = .91), and the 8-ft up-and-go test (d = .63). No changes were measured for HbA1c or C-reactive protein. No changes were observed for flexibility (chair sit and reach, back scratch tests), 6-min walk test, maximum handgrip test, anxiety, depression, fatigue, or self-efficacy for exercise. CONCLUSIONS: Home-based muscle-strengthening exercise led to favorable and clinically relevant improvements in 3 of 7 physical function assessments. Physical function, body composition, blood biomarkers, and patient-reported outcomes were feasible to measure. These fitness improvements were observed over a relatively short time frame of 10 weeks.


Assuntos
Neoplasias do Endométrio , Telemedicina , Neoplasias do Endométrio/terapia , Exercício Físico , Terapia por Exercício , Feminino , Força da Mão , Humanos , Pessoa de Meia-Idade , Força Muscular , Aptidão Física , Qualidade de Vida , Sobreviventes
8.
Proc Natl Acad Sci U S A ; 116(45): 22491-22499, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31636174

RESUMO

Rational design of supramolecular nanomaterials fundamentally depends upon an atomic-level understanding of their structure and how it responds to chemical modifications. Here we studied a series of crystalline diblock copolypeptoids by a combination of sequence-controlled synthesis, cryogenic transmission electron microscopy, and molecular dynamics simulation. This family of amphiphilic polypeptoids formed free-floating 2-dimensional monolayer nanosheets, in which individual polymer chains and their relative orientations could be directly observed. Furthermore, bromine atom side-chain substituents in nanosheets were directly visualized by cryogenic transmission electron microscopy, revealing atomic details in position space inaccessible by conventional scattering techniques. While the polypeptoid backbone conformation was conserved across the set of molecules, the nanosheets exhibited different lattice packing geometries dependent on the aromatic side chain para substitutions. Peptoids are inherently achiral, yet we showed that sequences containing an asymmetric aromatic substitution pattern pack with alternating rows adopting opposite backbone chiralities. These atomic-level insights into peptoid nanosheet crystal structure provide guidance for the future design of bioinspired nanomaterials with more precisely controlled structures and properties.


Assuntos
Nanoestruturas/química , Peptoides/química , Microscopia Crioeletrônica , Simulação de Dinâmica Molecular , Nanoestruturas/ultraestrutura , Peptoides/síntese química , Polímeros/síntese química , Polímeros/química
9.
Gynecol Oncol ; 160(3): 655-659, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33422300

RESUMO

OBJECTIVE: To identify the most common causes of death and potentially modifiable risk factors in endometrial cancer patients. METHODS: 745 women diagnosed with incident endometrial cancer were enrolled in a population-based study from 1991 to 1994. Participants completed structured interviews about 1 year after diagnosis. Study files were linked with the National Death Index to identify dates and causes of death through 2016. Proportional hazards regression was used to estimate hazard rate ratios for cause of death adjusting for age and stage of disease. Hazard ratios were also examined according to comorbidities. RESULTS: Of the 745 women, 450 were deceased after a median of 19.9 years. The two most common causes of death were cardiovascular disease (N = 145, 32%) and any cancer (N = 135, 30%), with only 10% of women dying from endometrial cancer (N = 46). Obesity, diabetes and smoking increased risk of all-cause mortality (HRR 1.77, 95%CI 1.36-2.31; HRR 1.74, 95%CI 1.34-2.27; HRR 1.59, 95%CI 1.16-2.17). Diabetes also increased risk of cardiovascular disease-specific mortality (HRR 1.98, 95%CI 1.38-3.08), but not endometrial cancer mortality (HRR 0.55, 95%CI 0.21-1.48). Neither obesity nor smoking was associated with increased risk of cardiovascular disease-specific mortality (HRR 1.46, 95%CI 0.92-2.32; HRR 1.21, 95%CI 0.67-2.18) nor endometrial-cancer specific mortality (HRR 1.81, 95%CI 0.83-3.93; HRR 0.61, 95%CI 0.17-2.15). CONCLUSIONS: Endometrial cancer patients were 3 times more likely to die of cardiovascular disease than endometrial cancer. Obesity, smoking and diabetes increase the risk of death in these patients and are potentially modifiable. Clinical trials should be developed that incorporate counseling regarding these risk factors into survivorship care to determine impact on mortality.


Assuntos
Causas de Morte/tendências , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco
10.
Gynecol Oncol ; 160(1): 271-278, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33077260

RESUMO

In approximately ten months' time, the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected over 34 million people and caused over one million deaths worldwide. The impact of this virus on our health, relationships, and careers is difficult to overstate. As the economic realities for academic medical centers come into focus, we must recommit to our core missions of patient care, education, and research. Fellowship education programs in gynecologic oncology have quickly adapted to the "new normal" of social distancing using video conferencing platforms to continue clinical and didactic teaching. United in a time of crisis, we have embraced systemic change by developing and delivering collaborative educational content, overcoming the limitations imposed by institutional silos. Additional innovations are needed in order to overcome the losses in program surgical volume and research opportunities. With the end of the viral pandemic nowhere in sight, program directors can rethink how education is best delivered and potentially overhaul aspects of fellowship curriculum and content. Similarly, restrictions on travel and the need for social distancing has transformed the 2020 fellowship interview season from an in-person to a virtual experience. During this time of unprecedented and rapid change, program directors should be particularly mindful of the needs and health of their trainees and consider tailoring their educational experiences accordingly.


Assuntos
COVID-19 , Bolsas de Estudo/métodos , Bolsas de Estudo/normas , Ginecologia/educação , Internato e Residência/normas , Oncologia/educação , Estados Unidos
11.
Proc Natl Acad Sci U S A ; 115(22): 5647-5651, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29760077

RESUMO

The conformations adopted by the molecular constituents of a supramolecular assembly influence its large-scale order. At the same time, the interactions made in assemblies by molecules can influence their conformations. Here we study this interplay in extended flat nanosheets made from nonnatural sequence-specific peptoid polymers. Nanosheets exist because individual polymers can be linear and untwisted, by virtue of polymer backbone elements adopting alternating rotational states whose twists oppose and cancel. Using molecular dynamics and quantum mechanical simulations, together with experimental data, we explore the design space of flat nanostructures built from peptoids. We show that several sets of peptoid backbone conformations are consistent with their being linear, but the specific combination observed in experiment is determined by a combination of backbone energetics and the interactions made within the nanosheet. Our results provide a molecular model of the peptoid nanosheet consistent with all available experimental data and show that its structure results from a combination of intra- and intermolecular interactions.


Assuntos
Simulação de Dinâmica Molecular , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Peptoides/química , Materiais Biomiméticos/química , Polímeros , Estrutura Secundária de Proteína
12.
Soft Matter ; 16(4): 907-913, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31854427

RESUMO

Biological systems have evolved sophisticated molecular assemblies capable of exquisite molecular recognition across length scales ranging from angstroms to microns. For instance, the self-organization of glycolipids and glycoproteins on cell membranes allows for molecular recognition of a diversity of ligands ranging from small molecules and proteins to viruses and whole cells. A distinguishing feature of these 2D surfaces is they achieve exceptional binding selectivity and avidity by exploiting multivalent binding interactions. Here we develop a 2D ligand display platform based on peptoid nanosheets that mimics the structure and function of the cell membrane. A variety of small-molecule lipid-conjugates were co-assembled with the peptoid chains to create a diversity of functionalized nanosheet bilayers with varying display densities. The functional heads of the lipids were shown to be surface-exposed, and the carbon tails immobilized into the hydrophobic interior. We demonstrate that saccharide-functionalized nanosheets (e.g., made from globotriaosylsphingosine or 1,2-dipalmitoyl-sn-glycero-3-phospho((ethyl-1',2',3'-triazole)triethyleneglycolmannose)) can have very diverse binding properties, exhibiting specific binding to multivalent proteins as well as to intact bacterial cells. Analysis of sugar display densities revealed that Shiga toxin 1 subunit B (a pentameric protein) and FimH-expressing Escherichia coli (E. coli) bind through the cooperative binding behavior of multiple carbohydrates. The ability to readily incorporate and display a wide variety of lipidated cargo on the surface of peptoid nanosheets makes this a convenient route to soluble, cell-surface mimetic materials. These materials hold great promise for drug screening, biosensing, bioremediation, and as a means to combat pathogens by direct physical binding through a well-defined, multivalent 2D material.


Assuntos
Carboidratos/química , Lipídeos/química , Nanoestruturas/química , Peptoides/química , Adesinas de Escherichia coli/química , Adesinas de Escherichia coli/genética , Biomimética , Escherichia coli/genética , Proteínas de Fímbrias/química , Proteínas de Fímbrias/genética , Interações Hidrofóbicas e Hidrofílicas , Toxina Shiga II/química , Toxina Shiga II/genética , Açúcares/química
13.
Int J Gynecol Cancer ; 30(4): 525-532, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32122951

RESUMO

BACKGROUND: Recurrent gynecologic cancer patients experience symptoms that affect psychologic, emotional, social, and physical well-being. Chemotherapy can further exacerbate these symptoms. Poor mood, pain, and fatigue are linked and are detrimental to quality of life. Interventions targeting these symptoms may improve patient-reported outcomes and performance status. OBJECTIVES: To determine the ability of a humorous digital media attention diversion to improve symptom domains of positive and negative mood during chemotherapy for patients with recurrent gynecologic cancers. STUDY DESIGN: This randomized, crossover clinical trial enrolled women with recurrent gynecologic cancers. Subjects participated over three cycles of chemotherapy. The primary outcome was the change in mood on the validated Positive and Negative Affect Scale-Extended (PANAS-X) instrument, which measures positive and negative affect domains. All subjects completed the PANAS-X after receiving chemotherapy during cycle 1 on study. In atudy arm 1, subjects watched their choice of humorous movies on a digital media device while receiving chemotherapy during cycle 2 on study. They selected from non-humorous movies during cycle 3 on study. In arm 2, the order of movies was reversed. After each cycle, mood, fatigue, and other patient-reported outcomes were assessed for comparison with baseline measurements. RESULTS: The target enrollment of 66 subjects was achieved. Subjects watched humorous content for an average of 96.0 min and non-humorous content for an average of 62.5 min. Negative mood improved after exposure to humorous (p=0.017) and non-humorous content (p=0.001). Patient-reported fear also improved after exposure to both humorous (p=0.038) and non-humorous content (p=0.002). Subjects reported higher use of affiliating and self-effacing humor types. CONCLUSIONS: Offering patients a choice of digital media during chemotherapy significantly improved negative mood and fear. This was seen with both humorous and non-humorous content. This low-cost and low-risk intervention should be implemented as an attention diversion to improve negative mood and fear for patients receiving chemotherapy.


Assuntos
Afeto , Atenção , Medo/psicologia , Neoplasias dos Genitais Femininos/psicologia , Neoplasias dos Genitais Femininos/terapia , Terapia do Riso/métodos , Filmes Cinematográficos , Recidiva Local de Neoplasia/psicologia , Recidiva Local de Neoplasia/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Comunicação , Estudos Cross-Over , Feminino , Neoplasias dos Genitais Femininos/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico
14.
J Am Chem Soc ; 141(49): 19436-19447, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31765162

RESUMO

Sequence-defined peptoids, or N-substituted glycines, are an attractive class of bioispired polymer due to their biostability and efficient synthesis. However, the de novo design of folded peptoids with precise three-dimensional structures has been hindered by limited means to deterministically control backbone conformation. Peptoid folds are generally destabilized by the cis/trans backbone-amide isomerization, and few side-chains are capable of enforcing a specific amide conformation. Here, we show that a novel class of cationic alkyl ammonium ethyl side-chains demonstrates significant enforcement of the cis-amide backbone (Kcis/trans up to 70) using an unexpected ensemble of weak intramolecular CH-O and/or NH-O hydrogen bonds between the side-chain and the backbone carbonyl moieties. These interactions are evidenced by X-ray crystallography, variable-temperature NMR spectroscopy, and DFT calculations. Moreover, these side-chains are inexpensive, structurally diverse, hydrophilic, and can be integrated into longer peptoid sequences via solid-phase synthesis. Notably, we extended these concepts to synthesize a water-soluble peptoid 10-mer that adopts one predominant fold in solution, as determined by multidimensional NMR spectroscopy. This decamer, to the best of our knowledge, is the longest linear peptoid sequence atomically characterized to retain a well-folded structure. These findings fill a critical gap in peptoid folding and should propel the development of peptoid applications in a broad range of contexts, from pharmaceutical to material sciences.


Assuntos
Amidas/química , Modelos Moleculares , Peptoides/síntese química , Dobramento de Proteína , Cristalografia por Raios X , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Glicinas N-Substituídas/síntese química , Glicinas N-Substituídas/química , Peptoides/química , Compostos de Amônio Quaternário/química , Técnicas de Síntese em Fase Sólida , Estereoisomerismo , Termodinâmica
15.
Biopolymers ; 110(6): e23266, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30835823

RESUMO

Like polypeptides, peptoids, or N-substituted glycine oligomers, have intrinsic conformational preferences due to their amide backbones and close spacing of side chain substituents. However, the conformations that peptoids adopt are distinct from polypeptides due to several structural differences: the peptoid backbone is composed of tertiary amide bonds that have trans and cis conformers similar in energy, they lack a backbone hydrogen bond donor, and have an N-substituent. To better understand how these differences manifest in actual peptoid structures, we analyzed 46 high quality, experimentally determined peptoid structures reported in the literature to extract their backbone conformational preferences. One hundred thirty-two monomer dihedral angle pairs were compared to the calculated energy landscape for the peptoid Ramachandran plot, and were found to fall within the expected minima. Interestingly, only two regions of the backbone dihedral angles ϕ and ψ were found to be populated that are mirror images of each other. Furthermore, these two conformers are present in both cis and trans forms. Thus, there are four primary conformers that are sufficient to describe almost all known backbone conformations for peptoid oligomers, despite conformational constraints imposed by a variety of side chains, macrocyclization, or crystal packing forces. Because these conformers are predominant in peptoid structure, and are distinct from those found in protein secondary structures, we propose a simple naming system to aid in the description and classification of peptoid structure.


Assuntos
Peptoides/química , Cristalografia por Raios X , Ligação de Hidrogênio , Peptídeos/química , Estrutura Secundária de Proteína , Estereoisomerismo
16.
Gynecol Oncol ; 152(2): 293-297, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30497792

RESUMO

OBJECTIVE: Returning home after surgery is a desirable patient-centered outcome associated with decreased costs compared to non-home discharge. Our objective was to develop a preoperative risk-scoring model predicting non-home discharge after surgery for gynecologic malignancy. METHODS: Women who underwent surgery involving hysterectomy for gynecologic malignancy from 2013 to 2015 were identified from the Michigan Surgical Quality Collaborative database. Patients were divided by discharge destination, and a multivariable logistic regression model was developed to create a nomogram to assign case-specific risk scores. The model was validated using the National Surgical Quality Improvement Program (NSQIP) database. RESULTS: Non-home discharge occurred in 3.1% of 2134 women. The proportion of non-home discharges did not differ by cancer diagnosis (uterine 3.5%, ovarian 2.5%, and cervical 1.6%, p = 0.2). Skilled nursing facilities were the most common non-home destination (68.2%). Among patients with comorbidities (hypertension, diabetes, coronary artery disease, chronic obstructive pulmonary disease /dyspnea, arrhythmia, and history of deep vein thrombosis/pulmonary embolism), non-home discharge was more common in women with 1 (adjusted OR [aOR] 3.4; p = 0.03) or ≥2 of these comorbidities (aOR 5.1; p = 0.003) compared to none. Non-home discharge was more common after laparotomy (aOR 6.7; p < 0.0001) than laparoscopy, and in those aged ≥70 years (aOR 3.4; p < 0.0001) with American Society of Anesthesiologists class ≥ 3 (aOR 4.5; p = 0.0004) and dependent functional status (aOR 8.7; p < 0.0001). The model C-statistic was 0.89. When the model was applied to 4248 eligible patients from the NSQIP dataset, the C-statistic was 0.84 (95% CI: 0.79-0.89). CONCLUSIONS: Non-home discharge after surgery for gynecologic malignancy was predicted with high accuracy in this retrospective analysis.


Assuntos
Neoplasias dos Genitais Femininos/cirurgia , Histerectomia/métodos , Alta do Paciente , Idoso , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Medição de Risco
17.
Gynecol Oncol ; 152(1): 133-138, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30424895

RESUMO

OBJECTIVE: Report the up-to-date trends in surgical approach for cervical cancer and compare outcomes between open and minimally invasive routes. METHODS: Radical Hysterectomy (RH) cases from the National Inpatient Sample (NIS) dataset between 2012 and 2015 were grouped into abdominal (ARH) and Minimally Invasive Surgery (MIS). The MIS group was subdivided as "Laparoscopic", "Robotic", and "Converted". Univariate and multivariable logistic regression were used to analyze differences in complication rates. The National Surgical Quality Improvement Dataset 2015 was used for validation. RESULTS: A total of 7180 cases from NIS were identified. Overall, there was 44% decline in RH cases from 2012 (n = 2220) to 2015 (n = 1255). A proportionate increase in robotic cases from 31.5% in 2012 to 41.4% in 2015 was noted. By intention to treat analysis, the rate of at least one complication for abdominal cases was 24.8% compared to 10% for MIS (p < 0.001). On multivariate analysis, abdominal cases had higher odd of any one complication (aOR 2.9,95% CI 2.12-4.00), medical complication (aOR 3.25,95% CI 2.15-4.19), infectious complication (aOR 3.76,95% CI 2.1-6.1) but not for surgical complications (aOR 1.7,95% CI 0.5-5.6). AH resulted in longer hospital stay compared to MIS (4.3 vs 1.9 days, p < 0.001). Median cost of AH was $12,624, laparoscopic $12,873, robotic $14,029 and converted cases $17,036. NSQIP analysis supplemented the outcomes to 30-days and showed similar findings. CONCLUSIONS: Perioperative complications are significantly lower for MIS procedures. These data should be used for contemporary cost-effective analysis and comprehensive counseling regarding risks and benefits of the surgical approach for cervical cancer.


Assuntos
Histerectomia/tendências , Neoplasias do Colo do Útero/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Custos de Cuidados de Saúde , Humanos , Histerectomia/efeitos adversos , Histerectomia/economia , Pacientes Internados , Laparoscopia/economia , Laparoscopia/tendências , Modelos Logísticos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Procedimentos Cirúrgicos Robóticos/economia , Procedimentos Cirúrgicos Robóticos/tendências
18.
Gynecol Oncol ; 152(1): 106-111, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30404721

RESUMO

PURPOSE: To analyze National Cancer Institute (NCI) funding distributions to gynecologic cancers compared to other cancers from 2007 to 2014. METHODS: The NCI's Surveillance, Epidemiology and End Results (SEER), Cancer Trends Progress Report, and Funding Statistics were used to analyze 18 cancer sites. Site-specific mortality to incidence ratios (MIR) were normalized per 100 cases and multiplied by person-years of life lost to derive cancer-specific lethality. NCI funding was divided by its lethality to calculate Funding to Lethality scores for gynecologic malignancies and compared to 15 other cancer sites. RESULTS: Ovarian, cervical, and uterine cancers ranked 10th (score 0.097, SD 0.008), 12th (0.087, SD 0.009), and 14th (0.057, SD 0.006) for average Funding to Lethality scores. The highest average score was for prostate cancer (score 1.182, SD 0.364). In U.S. dollars per 100 incident cases, prostate cancer received an average of $1,821,000 per person-years of life lost, while ovarian cancer received $97,000, cervical cancer $87,000, and uterine cancer $57,000. Ovarian and cervical cancers had lower average Funding to Lethality scores compared to nine other cancers, while uterine cancer was lower than 13 other cancers (p < 0.01 for all comparisons). Analyses of eight-, five-, and three-year trends for gynecologic cancers showed nearly universal decreasing Funding to Lethality scores. CONCLUSION: Funding to Lethality scores for gynecologic cancers are significantly lower than other cancer sites, indicating a disparity in funding allocation that persists over the most recent eight years of available data. Prompt correction is required to ensure critical discoveries for women with gynecologic cancers.


Assuntos
Neoplasias dos Genitais Femininos/mortalidade , Apoio à Pesquisa como Assunto , Feminino , Humanos , Masculino , Alocação de Recursos
19.
Int J Gynecol Cancer ; 29(1): 102-107, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30640690

RESUMO

OBJECTIVES: To determine if linear measurements of adiposity from pre-operative imaging can improve anticipation of surgical difficulty among endometrial cancer patients. METHODS: Eighty patients with newly diagnosed endometrial cancer were enrolled. Routine pre-operative imaging (MRI or CT) was performed. Radiologic linear measurements of the following were obtained: anterior-to-posterior skin distance; anterior skin to anterior edge of L5 distance (total anterior); anterior peritoneum to anterior edge of L5 distance (visceral obesity); and posterior edge of L5 to posterior skin distance (total posterior). Surgeons completed questionnaires quantifying preoperative anticipated operative difficulty and postoperative reported operative difficulty. The primary objective was to assess for a correlation between linear measurements of visceral fat and reported operative difficulty. RESULTS: Seventy-nine patients had questionnaires completed, preoperative imaging obtained, and surgery performed. Univariate analysis showed all four linear measurements, body mass index, weight, and anticipated operative difficulty were associated with increased reported operative difficulty (P< 0.05). Multivariate analysis demonstrated that body mass index and linear measurements visceral obesity and total posterior were independently associated with increased reported operative difficulty (P< 0.05). Compared with body mass index, the visceral obesity measurement was more sensitive and specific for predicting increased reported operative difficulty (visceral obesity; sensitivity 54%, specificity 91 %; body mass index; sensitivity 38%, specificity 89%). A difficulty risk model combining body mass index, visceral obesity, and total posterior demonstrated better predictive performance than any individual preoperative variable. CONCLUSIONS: Simple linear measurements of visceral fat obtained from preoperative imaging are more predictive than body mass index alone in anticipating surgeon-reported operative difficulty. These easily obtained measurements may assist in preoperative decision making in this challenging patient population.


Assuntos
Carcinossarcoma/diagnóstico por imagem , Cistadenocarcinoma Seroso/diagnóstico por imagem , Neoplasias do Endométrio/diagnóstico por imagem , Gordura Intra-Abdominal/diagnóstico por imagem , Obesidade/complicações , Complicações Pós-Operatórias , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Carcinossarcoma/cirurgia , Cistadenocarcinoma Seroso/cirurgia , Neoplasias do Endométrio/cirurgia , Feminino , Seguimentos , Humanos , Laparoscopia/métodos , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
20.
J Am Chem Soc ; 140(2): 827-833, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29309136

RESUMO

Peptoid polymers are often crystalline in the solid-state as examined by X-ray scattering, but thus far, there has been no attempt to identify a common structural motif among them. In order to probe the relationship between molecular structure and crystal structure, we synthesized and analyzed a series of crystalline peptoid copolymers, systematically varying peptoid side-chain length (S) and main-chain length (N). We also examined X-ray scattering data from 18 previously reported peptoid polymers. In all peptoids, we found that the unit cell dimensions, a, b, and c, are simple functions of S and N: a (Å) = 4.55, b (Å) = [2.98]N + 0.35, and c (Å) = [1.86]S + 5.5. These relationships, which apply to both bulk crystals and self-assembled nanosheets in water, indicate that the molecules adopt extended, planar conformations. Furthermore, we performed molecular dynamics simulations (MD) of peptoid polymer lattices, which indicate that all backbone amides adopt the cis conformation. This is a surprising conclusion, because previous studies on isolated molecules indicated an energetic preference for the trans conformer. This study demonstrates that when packed into supramolecular lattices or crystals, peptoid polymers prefer to adopt a regular, extended, all-cis secondary structure.

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