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PURPOSE: Treatment of non–muscle-invasive bladder cancer (NMIBC) is guided by risk stratification using clinical and pathologic criteria. This study aimed to develop a natural language processing (NLP) model for identifying patients with high-risk NMIBC retrospectively from unstructured electronic medical records (EMRs) and to apply the model to describe patient and tumor characteristics. METHODS: We used three independent EMR-derived data sets including adult patients with a bladder cancer diagnosis in 2011-2020 for NLP model development and training (n = 140), validation (n = 697), and application for the retrospective cohort analysis (n = 4,402). Deep learning methods were used to train NLP recognition of medical chart terminology to identify seven high-risk NMIBC criteria; model performance was assessed using the F1 score, weighted across features. An algorithm was then used to classify each patient as high-risk NMIBC (yes/no). Manually reviewed records served as the gold standard. RESULTS: The F1 scores after model training were >0.7 for all but one uncommon feature (prostatic urethral involvement). The highest area under the receiver operating curves (AUC) was observed for Ta (0.897) and T1 (0.897); the lowest AUC was for carcinoma in situ (CIS; 0.617). For high-risk NMIBC classification, positive predictive value was 79.4%, negative predictive value was 93.2%, and false-positive rate was 8.9%. Sensitivity and specificity were 83.7% and 91.1%, respectively. Of 748 patients manually confirmed as having high-risk NMIBC, 196 (26%) had CIS (of whom 19% also had T1 and 23% also had Ta disease); 552 tumors (74%) had no associated CIS. CONCLUSION: The NLP model, combined with a rule-based algorithm, identified high-risk NMIBC with good performance and will enable future work to study real-world treatment patterns and clinical outcomes for high-risk NMIBC. [ABSTRACT FROM AUTHOR]

ZhuH is a priming ketosynthase that initiates the elongation of the polyketide chain in the biosynthetic pathway of a type II polyketide, R1128. The crystal structure of ZhuH in complex with the priming substrate acetyl-CoA reveals an extensive loop region at the dimer interface that appears to affect the selectivity for the primer unit. Acetyl-CoA is bound in a 20 A-long channel, which placed the acetyl group against the catalytic triad. Analysis of the primer unit binding site in ZhuH suggests that it can accommodate acyl chains that are two to four carbons long. Selectivity and primer unit size appear to involve the side chains of three residues on the loops close to the dimer interface that constitute the bottom of the substrate binding pocket.

Research has been conducted on the polyketide backbone. The mechanistic principles associated with the R1128 polyketide backbone biosynthesis initiating have been investigated and the results are reported.

The octanol-water partition coefficients of dibenzyldiaza-18-crown-6 (PhCH2[N18N]CH2Ph), di(dodecyldiaza-18-crown-6(C12H25[N18N]C12H25), HOOC(CH2)11[N18N]CH2)11COOH, C12H25[N18N](CH2)12[N18N](C12)12[N18N]C12H25, and others are observed. Their apparent preference for octanol indicates that they are 10,0000 times more attracted to the phospholipid bilayer membrane. Sodium transport rates were established using a bilayer clamp method. Sodium cation binding and transport by ionophores data is given.

Abstract Background While prior research has provided important information about readmission rates following percutaneous coronary intervention, reports regarding charges and length of stay for readmission beyond 30 days post-discharge for patients in a large cohort are limited. The objective of this study was to characterize the rehospitalization of patients with acute coronary syndrome receiving percutaneous coronary intervention in a U.S. health benefit plan. Methods This study retrospectively analyzed administrative claims data from a large US managed care plan at index hospitalization, 30-days, and 31-days to 15-months rehospitalization. A valid Diagnosis Related Group code (version 24) associated with a PCI claim (codes 00.66, 36.0X, 929.73, 929.75, 929.78–929.82, 929.84, 929.95/6, and G0290/1) was required to be included in the study. Patients were also required to have an ACS diagnosis on the day of admission or within 30 days prior to the index PCI. ACS diagnoses were classified by the International Statistical Classification of Disease 9 (ICD-9-CM) codes 410.xx or 411.11. Patients with a history of transient ischemic attack or stroke were excluded from the study because of the focus only on ACS-PCI patients. A clopidogrel prescription claim was required within 60 days after hospitalization. Results Of the 6,687 ACS-PCI patients included in the study, 5,174 (77.4%) were male, 5,587 (83.6%) were Conclusions For ACS patients who underwent PCI, revascularization procedures represented a large portion of rehospitalizations. Revascularization procedures appear to be the most frequent, most costly, and earliest cause for rehospitalization after ACS-PCI.

Abstract Background Health outcomes could be improved if women at high risk for osteoporotic fracture were matched to effective treatment. This study determined the extent to which treatment for osteoporosis/osteopenia corresponded to the presence of specific risk factors for osteoporotic fracture. Methods This retrospective analysis of the United States 2007 National Health and Wellness Survey included women age ≥ 40 years who reported having a diagnosis of osteoporosis (69% of 3276) or osteopenia (31% of 3276). Patients were stratified by whether they were or were not taking prescription treatment for osteoporosis/osteopenia. Using 34 patient characteristics as covariates, logistic regression was used to determine factors associated with treatment. Results Current prescription treatment was reported by 1800 of 3276 (54.9%) women with osteoporosis/osteopenia. The following factors were associated with receiving prescription treatment: patient-reported diagnosis of osteoporosis (versus osteopenia); previous bone mineral density test; ≥ 2 fractures since age 50; older age; lower body mass index; better physical functioning; postmenopausal status; family history of osteoporosis; fewer comorbidities; prescription insurance coverage; higher total prescription count; higher ratio of prescription costs to monthly income; higher income; single status; previous visit to a rheumatologist or gynecologist; and 1 or 2 outpatient visits to healthcare provider (vs. none) in the prior 6 months. Glucocorticoid, tobacco, and daily alcohol use were risk factors for fracture that were not associated with treatment. Conclusions There is a mismatch between those women who could benefit from treatment for osteoporosis and those who are actually treated. For example, self-reported use of glucocorticoids, tobacco, and alcohol were not associated with prescription treatment of osteoporosis. Other clinical and socioeconomic factors were associated with treatment (e.g. prescription drug coverage and higher income) or not (e.g. comorbid osteoarthritis and anxiety) and could be opportunities to improve care.

We read with great interest the article 'Cost-Effectiveness of Osteoporosis Screening and Treatment with Hormone Replacement Therapy, Raloxifene, or Alendronate' by Mobley and colleagues in the March-April 2006 issue of [...]

Abstract Background Both raloxifene and bisphosphonates are indicated for the prevention and treatment of postmenopausal osteoporosis, however these medications have different efficacy and safety profiles. It is plausible that physicians would prescribe these agents to optimize the benefit/risk profile for individual patients. The objective of this study was to compare demographic and clinical characteristics of patients initiating raloxifene with those of patients initiating bisphosphonates for the prevention and treatment of osteoporosis. Methods This study was conducted using a retrospective cohort design. Female beneficiaries (45 years and older) with at least one claim for raloxifene or a bisphosphonate in 2003 through 2005 and continuous enrollment in the previous 12 months and subsequent 6 months were identified using a collection of large national commercial, Medicare supplemental, and Medicaid administrative claims databases (MarketScan®). Patients were divided into two cohorts, a combined commercial/Medicare cohort and a Medicaid cohort. Within each cohort, characteristics (demographic, clinical, and resource utilization) of patients initiating raloxifene were compared to those of patients initiating bisphosphonate therapy. Group comparisons were made using chi-square tests for proportions of categorical measures and Wilcoxon rank-sum tests for continuous variables. Logistic regression was used to simultaneously examine factors independently associated with initiation of raloxifene versus a bisphosphonate. Results Within both the commercial/Medicare and Medicaid cohorts, raloxifene patients were younger, had fewer comorbid conditions, and fewer pre-existing fractures than bisphosphonate patients. Raloxifene patients in both cohorts were less likely to have had a bone mineral density (BMD) screening in the previous year than were bisphosphonate patients, and were also more likely to have used estrogen or estrogen/progestin therapy in the previous 12 months. These differences remained statistically significant in the multivariate model. Conclusion In this sample of patients enrolled in commercial, Medicare, and Medicaid plans, patients who initiated raloxifene treatment differed from those initiating bisphosphonates. Raloxifene patients were younger, had better overall health status and appeared to be less likely to have risk factors for new osteoporotic fractures than bisphosphonate patients. Differences in the clinical profiles of these agents may impact prescribing decisions. Investigators using observational data to make comparisons of treatment outcomes associated with these medications should take these important differences in patient characteristics into consideration.

Abstract Background Limited data are available regarding the cost-effectiveness of preventative therapies for postmenopausal women with osteopenia. The objective of the present study was to evaluate the cost-effectiveness of raloxifene, alendronate and conservative care in this population. Methods We developed a microsimulation model to assess the incremental cost and effectiveness of raloxifene and alendronate relative to conservative care. We assumed a societal perspective and a lifetime time horizon. We examined clinical scenarios involving postmenopausal women from 55 to 75 years of age with bone mineral density T-scores ranging from -1.0 to -2.4. Modeled health events included vertebral and nonvertebral fractures, invasive breast cancer, and venous thromboembolism (VTE). Raloxifene and alendronate were assumed to reduce the incidence of vertebral but not nonvertebral fractures; raloxifene was assumed to decrease the incidence of breast cancer and increase the incidence of VTEs. Cost-effectiveness is reported in $/QALYs gained. Results For women 55 to 60 years of age with a T-score of -1.8, raloxifene cost approximately $50,000/QALY gained relative to conservative care. Raloxifene was less cost-effective for women 65 and older. At all ages, alendronate was both more expensive and less effective than raloxifene. In most clinical scenarios, raloxifene conferred a greater benefit (in QALYs) from prevention of invasive breast cancer than from fracture prevention. Results were most sensitive to the population's underlying risk of fracture and breast cancer, assumed efficacy and costs of treatment, and the discount rate. Conclusion For 55 and 60 year old women with osteopenia, treatment with raloxifene compares favorably to interventions accepted as cost-effective.

OBJECTIVES: Our aim was to describe the incidence of Alzheimer's disease (AD) in the United States, overall and by geographic region. DESIGN: We conducted retrospective analyses of administrative claims data for a 5% random sample of US Medicare beneficiaries aged 65 years or older. AD incidence, defined as a diagnosis for AD (International Classification of Disease, Ninth Revision, Clinical Modification code 331.0×) in a given year, with no AD diagnosis in the beneficiary's entire medical history, was estimated for each calendar year between 2007 and 2014. Beneficiaries were required to be enrolled in Medicare for the calendar year of evaluation as well as the preceding 12 months. In addition, a cross‐sectional assessment of geographic variation in AD incidence was conducted for 2014. For each population area (specifically, core‐based statistical area, as defined by the US Census Bureau), AD incidence was estimated overall, as well as adjusted for differences in underlying patient demographics and metrics of access to care and quality of care. Changes in AD incidence from 2007 were also estimated. SETTING: US fee‐for‐service Medicare. Participants: US Medicare beneficiaries aged 65 years or older with no history of AD. RESULTS: Overall, the diagnosed incidence of AD decreased over time, from 1.53% in 2007 to 1.09% in 2014; trends were similar for most population areas. In 2014, the rates of AD incidence ranged from 0% to more than 3% across population areas, with the highest observed incidence rates in areas of the Midwest and the South. Statistical models explain little of the geographic variation, although following adjustment, the incidence rates increased the most (in relative terms) in rural areas of western states. CONCLUSION: Our findings are consistent with previously reported estimates of incidence of AD in the United States and its recent declining trend. Additionally, the study highlights the considerable geographic variation in the incidence of AD in the United States and suggests that further research is needed to better understand the determinants of this geographic variation. J Am Geriatr Soc 68:346–353, 2020 [ABSTRACT FROM AUTHOR]

The alkali metal cations [Na.sup.+] and [K.sup.+] have several important physiological roles, including modulating enzyme activity. Recent work has suggested that alkali metal cations may be coordinated by [Pi] systems, such as the aromatic amino acid side chains. The ability of [K.sup.+] to interact with an aromatic ring has been assessed by preparing a family of synthetic receptors that incorporate the aromatic side chains of phenylalanine, tyrosine, and tryptophan. These receptors are constructed around a diaza-18-crown-6 scaffold, which serves as the primary binding site for an alkali metal cation. The ability of the aromatic rings to coordinate a cation was determined by crystallizing each of the receptors in the presence of [K.sup.+] and by solving the solid state structures. In all cases, complexation of [K.sup.+] by the [Pi] system was observed. When possible, the structures of the unbound receptors also were determined for comparison. Further proof that the aromatic ring makes an energetically favorable interaction with the cation was obtained by preparing a receptor in which the arene was perfluorinated. Fluorination of the arene reverses the electrostatics, but the aromaticity is maintained. The fluorinated arene rings do not coordinate the cation in the solid state structure of the [K.sup.+] complex. Thus, the results of the predicted electrostatic reversal were confirmed. Finally, the biological implications of the alkali metal cation-[Pi] interaction are addressed.

Two novel, synthetic, cation-conducting channel compounds that incorporate fluorescent probes was investigated to provide proper assessment of a model channel's position within a phospholipid bilayer. Results of the investigation indicate that the channel headgroup in located in an environment intermediate in polarity between methanol and ethanol. Furthermore, fluorescence energy transfer is monomeric.

The activity of two compounds of tris(macrocycle) channels in phosphatidylglycerol/phosphatidylcholine bilayers were analyzed to characterize the role of the distal macroring in planar bilayer conductance. Nuclear magnetic resonance spectroscopic analysis of the channels compounds indicated the presence of a gate cation passage that was formed by conformational changes in the tris(macrocycle) channels. The model systems acted like protein channels that undergo intramolecular conformational and positional changes in the lipid bilayer.

The solid state structures and complexation behaviour for seven diaza-18-crown-6-ethers with aromatic sidearms are described.