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1.
Adv Ther ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833143

RESUMO

INTRODUCTION: Breast cancer is currently the leading cause of global cancer incidence. Breast cancer has negative consequences for society and economies internationally due to the high burden of disease which includes adverse epidemiological and economic implications. Our aim is to systematically review the estimated economic burden of breast cancer in the United States (US), Canada, Australia, and Western Europe (United Kingdom, France, Germany, Spain, Italy, Norway, Sweden, Denmark, Netherlands, and Switzerland), with an objective of discussing the policy and practice implications of our results. METHODS: We included English-language published studies with cost as a focal point using a primary data source to inform resource usage of women with breast cancer. We focussed on studies published since 2017, but with reported costs since 2012. A systematic search conducted on 25 January 2023 identified studies relating to the economic burden of breast cancer in the countries of interest. MEDLINE, Embase, and EconLit databases were searched via Ovid. Study quality was assessed based on three aspects: (1) validity of cost findings; (2) completeness of direct cost findings; and (3) completeness of indirect cost findings. We grouped costs based on country, cancer stage (early compared to metastatic), and four resource categories: healthcare/medical, pharmaceutical drugs, diagnosis, and indirect costs. Costs were standardized to the year 2022 in US (US$2022) and International (Int$2022) dollars. RESULTS: Fifty-three studies were included. Studies in the US (n = 19) and Canada (n = 9) were the majority (53%), followed by Western European countries (42%). Healthcare/medical costs were the focus for the majority (89%), followed by pharmaceutical drugs (25%), then diagnosis (17%) and indirect (17%) costs. Thirty-six (68%) included early-stage cancer costs, 17 (32%) included metastatic cancer costs, with 23% reporting costs across these cancer stages. No identified study explicitly compared costs across countries. Across cost categories, cost ranges tended to be higher in the US than any other country. Metastatic breast cancer was associated with higher costs than earlier-stage cancer. When indirect costs were accounted for, particularly in terms of productivity loss, they tended to be higher than any other estimated direct cost (e.g., diagnosis, drug, and other medical costs). CONCLUSION: There was substantial heterogeneity both within and across countries for the identified studies' designs and estimated costs. Despite this, current empirical literature suggests that costs associated with early initiation of treatment could be offset against potentially avoiding or reducing the overall economic burden of later-stage and more severe breast cancer. Larger scale, national, economic burden studies are needed, to be updated regularly to ensure there is an ongoing and evolving perspective of the economic burden of conditions such as breast cancer to inform policy and practice.

3.
JMIR Med Inform ; 11: e41576, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37335616

RESUMO

BACKGROUND: With the advent of electronic storage of medical records and the internet, patients can access web-based medical records. This has facilitated doctor-patient communication and built trust between them. However, many patients avoid using web-based medical records despite their greater availability and readability. OBJECTIVE: On the basis of demographic and individual behavioral characteristics, this study explores the predictors of web-based medical record nonuse among patients. METHODS: Data were collected from the National Cancer Institute 2019 to 2020 Health Information National Trends Survey. First, based on the data-rich environment, the chi-square test (categorical variables) and 2-tailed t tests (continuous variables) were performed on the response variables and the variables in the questionnaire. According to the test results, the variables were initially screened, and those that passed the test were selected for subsequent analysis. Second, participants were excluded from the study if any of the initially screened variables were missing. Third, the data obtained were modeled using 5 machine learning algorithms, namely, logistic regression, automatic generalized linear model, automatic random forest, automatic deep neural network, and automatic gradient boosting machine, to identify and investigate factors affecting web-based medical record nonuse. The aforementioned automatic machine learning algorithms were based on the R interface (R Foundation for Statistical Computing) of the H2O (H2O.ai) scalable machine learning platform. Finally, 5-fold cross-validation was adopted for 80% of the data set, which was used as the training data to determine hyperparameters of 5 algorithms, and 20% of the data set was used as the test data for model comparison. RESULTS: Among the 9072 respondents, 5409 (59.62%) had no experience using web-based medical records. Using the 5 algorithms, 29 variables were identified as crucial predictors of nonuse of web-based medical records. These 29 variables comprised 6 (21%) sociodemographic variables (age, BMI, race, marital status, education, and income) and 23 (79%) variables related to individual lifestyles and behavioral habits (such as electronic and internet use, individuals' health status and their level of health concern, etc). H2O's automatic machine learning methods have a high model accuracy. On the basis of the performance of the validation data set, the optimal model was the automatic random forest with the highest area under the curve in the validation set (88.52%) and the test set (82.87%). CONCLUSIONS: When monitoring web-based medical record use trends, research should focus on social factors such as age, education, BMI, and marital status, as well as personal lifestyle and behavioral habits, including smoking, use of electronic devices and the internet, patients' personal health status, and their level of health concern. The use of electronic medical records can be targeted to specific patient groups, allowing more people to benefit from their usefulness.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37093574

RESUMO

IMPORTANCE: Gender equity in obstetrics and gynecology remains a barrier to career mobility and workplace satisfaction. OBJECTIVE: This study aimed to evaluate gender equity for academic positions in female pelvic medicine and reconstructive surgery (FPMRS) divisions with an Accreditation Council for Graduate Medical Education-accredited fellowship in the United States. STUDY DESIGN: This was a cross-sectional observational study of all FPMRS divisions with an Accreditation Council for Graduate Medical Education-accredited fellowship program in the United States in July 2020 using publicly available demographic and academic data collected from online search engines. Gender equity in academic FPMRS was assessed by gender representation, academic appointment, and research productivity of each attending physician within the division. Research productivity was assessed using both the H-index with career length controlled for with the M-quotient. RESULTS: There were 348 attending physicians from 72 FPMRS divisions (198 female [56.9%], 150 male [43.1%]). A large percentage of female attending physicians were at the assistant professor level (75.8% [94 of 124]) when compared with their male counterparts (24.4% [30 of 124]; P < 0.001). Conversely, there were a larger percentage of male attending physicians (62.2% [56 of 90]) at the professor level when compared with their female counterparts (37.8% [34 of 90]; P < 0.001). There was no difference in research productivity between male and female attending physicians after controlling for career length with the M-quotient (P = 0.65). Only age (odds ratio, 1.14; 95% confidence interval, 1.05-1.24) and the M-quotient (odds ratio, 36.17, 95% confidence interval, 8.57-152.73) were significantly associated with professorship. CONCLUSIONS: Our study found that there are more female attending physicians in FPMRS and that most are assistant professors. Male and female FPMRS attending physicians had similar research productivity with respect to their career lengths. Gender was not a determinant for achieving a "professor" appointment.

5.
Eur J Heart Fail ; 25(2): 238-247, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36644849

RESUMO

AIMS: To compare the cost-effectiveness of immediate and 12-month delayed initiation of dapagliflozin treatment in patients with a history of hospitalization for heart failure (HHF) from the UK, Canadian, German, and Spanish healthcare perspectives. METHODS AND RESULTS: A cost-utility analysis was conducted using a decision-analytic Markov model with health states defined by Kansas City Cardiomyopathy Questionnaire scores, type 2 diabetes mellitus status and incidence of heart failure (HF) events. Patient-level data for patients with prior HHF from the Dapagliflozin And Prevention of Adverse-outcomes in Heart Failure (DAPA-HF) trial were used to inform the model inputs on clinical events and utility values. Healthcare costs were sourced from the relevant national reference databases and the published literature. Compared to standard therapy, immediate initiation of dapagliflozin decreased HHF (187 events), urgent HF visits (32 events) and cardiovascular mortality (18 events). Standard therapy was associated with lifetime costs of £13 224 and 4.02 quality-adjusted life years (QALYs). Twelve-month delayed initiation of dapagliflozin was associated with total discounted lifetime costs and QALYs of £16 660 and 4.61, respectively, compared to £16 912 and 4.66, respectively, for immediate initiation. Compared to standard therapy, immediate and 12-month delayed initiation of dapagliflozin yielded an incremental cost-effectiveness ratio (ICER) of £5779 and £5821, respectively. Compared to 12-month delayed initiation, immediate initiation of dapagliflozin had an ICER of £5263. Results were similar from the Canadian, German, and Spanish healthcare perspectives. CONCLUSION: Both immediate and 12-month delayed initiation of dapagliflozin are cost-effective. However, immediate initiation provides greater clinical benefits, with almost 10% additional QALYs gain, compared to 12-month delayed initiation of dapagliflozin and should be considered standard of care.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Humanos , Diabetes Mellitus Tipo 2/complicações , Análise Custo-Benefício , Insuficiência Cardíaca/tratamento farmacológico , Canadá
6.
Cerebellum ; 22(6): 1098-1108, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36156185

RESUMO

Differentiating multiple system atrophy (MSA) from related neurodegenerative movement disorders (NMD) is challenging. MRI is widely available and automated decision-tree analysis is simple, transparent, and resistant to overfitting. Using a retrospective cohort of heterogeneous clinical MRIs broadly sourced from a tertiary hospital system, we aimed to develop readily translatable and fully automated volumetric diagnostic decision-trees to facilitate early and accurate differential diagnosis of NMDs. 3DT1 MRI from 171 NMD patients (72 MSA, 49 PSP, 50 PD) and 171 matched healthy subjects were automatically segmented using Freesurfer6.0 with brainstem module. Decision trees employing substructure volumes and a novel volumetric pons-to-midbrain ratio (3D-PMR) were produced and tenfold cross-validation performed. The optimal tree separating NMD from healthy subjects selected cerebellar white matter, thalamus, putamen, striatum, and midbrain volumes as nodes. Its sensitivity was 84%, specificity 94%, accuracy 84%, and kappa 0.69 in cross-validation. The optimal tree restricted to NMD patients selected 3D-PMR, thalamus, superior cerebellar peduncle (SCP), midbrain, pons, and putamen as nodes. It yielded sensitivities/specificities of 94/84% for MSA, 72/96% for PSP, and 73/92% PD, with 79% accuracy and 0.62 kappa. There was correct classification of 16/17 MSA, 5/8 PSP, 6/8 PD autopsy-confirmed patients, and 6/8 MRIs that preceded motor symptom onset. Fully automated decision trees utilizing volumetric MRI data distinguished NMD patients from healthy subjects and MSA from other NMDs with promising accuracy, including autopsy-confirmed and pre-symptomatic subsets. Our open-source methodology is well-suited for widespread clinical translation. Assessment in even more heterogeneous retrospective and prospective cohorts is indicated.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Paralisia Supranuclear Progressiva , Humanos , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Paralisia Supranuclear Progressiva/diagnóstico , Estudos Retrospectivos , Diagnóstico Diferencial , Estudos Prospectivos , Voluntários Saudáveis , Imageamento por Ressonância Magnética/métodos , Árvores de Decisões
7.
ACS Omega ; 6(44): 29596-29608, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34778631

RESUMO

Development of multi-ligand metal-organic frameworks (MOFs) and derived heteroatom-doped composites as efficient non-noble metal-based catalysts is highly desirable. However, rational design of these materials with controllable composition and structure remains a challenge. In this study, novel hierarchical N-doped CuO/Cu composites were synthesized by assembling dual-ligand MOFs via a solvent-induced coordination modulation/low-temperature pyrolysis method. Different from a homogeneous system, our heterogeneous nucleation strategy provided more flexible and cost-effective MOF production and offered efficient direction/shape-controlled synthesis, resulting in a faster reaction and more complete conversion. After pyrolysis, they further transformed to a unique metal/carbon matrix with regular morphology and, as a hot template, guided the orderly generation of metal oxides, eliminating sintering and agglomeration of metal oxides and initiating a synergistic effect between the N-doped metal oxide/metal and carbon matrix. The prepared N-doped CuO/Cu catalysts held unique water resistance and superior catalytic activity (100% CO conversion at 140 °C).

8.
Clin Cardiol ; 44(5): 646-655, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33704817

RESUMO

BACKGROUND: Limited real-world data exist on healthcare resource utilization (HCRU) and associated costs of patients with heart failure (HF) with reduced ejection fraction (HFrEF) and preserved EF (HFpEF), including urgent HF visits, which are assumed to be less burdensome than HF hospitalizations (hHFs) HYPOTHESIS: This study aimed to quantify the economic burden of HFrEF and HFpEF, via a retrospective, longitudinal cohort study, using IBM® linked claims/electronic health records (Commercial and Medicare Supplemental data only). METHODS: Adult patients, indexed on HF diagnosis (ICD-10-CM: I50.x) from July 2012 through June 2018, with 6-month minimum baseline period and varying follow-up, were classified as HFrEF (I50.2x) or HFpEF (I50.3x) according to last-observed EF-specific diagnosis. HCRU/costs were assessed during follow-up. RESULTS: About 109 721 HF patients (22% HFrEF, 31% HFpEF, 47% unclassified EF; median 18 months' follow-up) were identified. There were 3.2 all-cause outpatient visits per patient-month (HFrEF, 3.3; HFpEF, 3.6); 69% of patients required inpatient stays (HFrEF, 80%; HFpEF, 78%). Overall, 11% of patients experienced hHFs (HFrEF, 23%; HFpEF, 16%), 9% experienced urgent HF visits (HFrEF, 15%; HFpEF, 12%); 26% were hospitalized less than 30 days after first urgent HF visit versus 11% after first hHF. Mean monthly total direct healthcare cost per patient was $9290 (HFrEF, $11 053; HFpEF, $7482). CONCLUSIONS: HF-related HCRU is substantial among contemporary real-world HF patients in US Commercial or Medicare supplemental health plans. Patients managed in urgent HF settings were over twice as likely to be hospitalized within 30 days versus those initially hospitalized, suggesting urgent HF visits are important clinical events and quality improvement targets.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Adulto , Idoso , Efeitos Psicossociais da Doença , Feminino , Coalizão em Cuidados de Saúde , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/economia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Humanos , Estudos Longitudinais , Masculino , Medicare , Prognóstico , Estudos Retrospectivos , Volume Sistólico , Estados Unidos/epidemiologia , Função Ventricular Esquerda
9.
Eur J Heart Fail ; 22(11): 2147-2156, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32749733

RESUMO

AIM: To estimate the cost-effectiveness of dapagliflozin added to standard therapy, vs. standard therapy only, in patients with heart failure (HF) with reduced ejection fraction (HFrEF), from the perspective of UK, German, and Spanish payers. METHODS AND RESULTS: A lifetime Markov model was built to estimate outcomes in patients with HFrEF. Health states were defined by Kansas City Cardiomyopathy Questionnaire total symptom score, type 2 diabetes and worsening HF events. The incidence of worsening HF and all-cause mortality was estimated using negative binomial regression models and parametric survival analysis, respectively. Direct healthcare costs (2019 British pounds/Euro) and patient-reported outcomes (EQ-5D) were sourced from the existing literature and the Dapagliflozin And Prevention of Adverse-outcomes in Heart Failure trial (DAPA-HF), respectively; the median duration of follow-up in DAPA-HF was 18.2 months (range: 0-27.8). Future costs and effects were discounted at 3.0% for the Spanish and German analyses and 3.5% for the UK analysis. In the UK setting, treatment with dapagliflozin was estimated to increase life-years and quality-adjusted life-years (QALYs) from 5.62 to 6.20 (+0.58) and 4.13 to 4.61 (+0.48), respectively, and reduce lifetime hospitalizations for HF (925 and 820 events per 1000 patients for placebo and dapagliflozin, respectively). Similar results were obtained for Germany and Spain. The incremental cost-effectiveness ratios were £5822, €5379 and €9406/QALY in the UK, Germany and Spain, respectively. In probabilistic sensitivity analyses, more than 90% of simulations were cost-effective at a willingness-to-pay threshold of £20 000/QALY in UK and €20 000/QALY in Germany and Spain. CONCLUSION: Dapagliflozin is likely to be a cost-effective treatment for HFrEF in the UK, German and Spanish healthcare systems.


Assuntos
Compostos Benzidrílicos , Glucosídeos , Insuficiência Cardíaca , Idoso , Compostos Benzidrílicos/economia , Compostos Benzidrílicos/uso terapêutico , Análise Custo-Benefício , Feminino , Alemanha , Glucosídeos/economia , Glucosídeos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/economia , Humanos , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Inibidores do Transportador 2 de Sódio-Glicose/economia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Espanha , Função Ventricular Esquerda
10.
BMC Nephrol ; 20(1): 31, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-30704421

RESUMO

BACKGROUND: People with chronic kidney disease (CKD) are at an increased risk of developing hyperkalaemia due to their declining kidney function. In addition, these patients are often required to reduce or discontinue guideline-recommended renin-angiotensin-aldosterone system inhibitor (RAASi) therapy due to increased risk of hyperkalaemia. This original research developed a model to quantify the health and economic benefits of maintaining normokalaemia and enabling optimal RAASi therapy in patients with CKD. METHODS: A patient-level simulation model was designed to fully characterise the natural history of CKD over a lifetime horizon, and predict the associations between serum potassium levels, RAASi use and long-term outcomes based on published literature. The clinical and economic benefits of maintaining sustained potassium levels and therefore avoiding RAASi discontinuation in CKD patients were demonstrated using illustrative, sensitivity and scenario analyses. RESULTS: Internal and external validation exercises confirmed the predictive capability of the model. Sustained potassium management and ongoing RAASi therapy were associated with longer life expectancy (+ 2.36 years), delayed onset of end stage renal disease (+ 5.4 years), quality-adjusted life-year gains (+ 1.02 QALYs), cost savings (£3135) and associated net monetary benefit (£23,446 at £20,000 per QALY gained) compared to an absence of RAASi to prevent hyperkalaemia. CONCLUSION: This model represents a novel approach to predicting the long-term benefits of maintaining normokalaemia and enabling optimal RAASi therapy in patients with CKD, irrespective of the strategy used to achieve this target, which may support decision making in healthcare.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Simulação por Computador , Hiperpotassemia/prevenção & controle , Modelos Biológicos , Potássio/sangue , Insuficiência Renal Crônica/complicações , Sistema Renina-Angiotensina/efeitos dos fármacos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Redução de Custos , Progressão da Doença , Feminino , Humanos , Hiperpotassemia/induzido quimicamente , Hiperpotassemia/economia , Hiperpotassemia/etiologia , Rim/fisiopatologia , Falência Renal Crônica/prevenção & controle , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/economia , Insuficiência Renal Crônica/terapia
11.
Appl Biochem Biotechnol ; 187(3): 856-869, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30088243

RESUMO

The symbiosis potential of microalgae and yeast is inherited with distinct advantages, providing an economical venue for their scale-up application. To assess the advantage of the mixed culture of microalgae Chlorella vulgaris and yeast Yarrowia lipolytica for treatment of liquid digestate of yeast industry (YILD) and cogeneration of biofuel feedstock, the cell growth characteristic, the nutrient removal efficiency, the energy storage potential of the mono, and mixed culture were investigated. The results indicated that the biomass concentration of the mixed culture (1.39-1.56 g/L of 5 times dilution group and 1.23-1.53 g/L of 10 times dilution group) was higher than those of mono cultures. The NH3-N and SO42- removal rates of the mixed culture were superior to mono cultures. Besides the higher lipid yield (0.073-0.154 g/L of 5 times dilution group and 0.112-0.183 g/L of 10 times dilution group), the higher yield of higher heating value (20.06-29.76 kJ/L of 5 times dilution group and 21.83-29.85 kJ/L of 10 times dilution group) was also obtained in the mixed culture. This study provides feasibility for remediation of YILD and cogeneration of biofuel feedstock using the mixed culture of microalgae and yeast.


Assuntos
Biocombustíveis , Chlorella vulgaris/crescimento & desenvolvimento , Chlorella vulgaris/metabolismo , Resíduos Industriais , Yarrowia/crescimento & desenvolvimento , Yarrowia/metabolismo , Leveduras/química , Técnicas de Cocultura , Estudos de Viabilidade , Nutrientes/isolamento & purificação , Nutrientes/metabolismo , Propriedades de Superfície
12.
J Med Econ ; 21(12): 1172-1182, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30160541

RESUMO

AIMS: Patients with heart failure are at increased risk of hyperkalemia, particularly when treated with renin-angiotensin-aldosterone system inhibitor (RAASi) agents. This study developed a model to quantify the potential health and economic value associated with sustained potassium management and optimal RAASi therapy in heart failure patients. MATERIALS AND METHODS: A patient-level, fixed-time increment stochastic simulation model was designed to characterize the progression of heart failure through New York Heart Association functional classes, and predict associations between serum potassium levels, RAASi use, and consequent long-term outcomes. Following internal and external validation exercises, model analyses sought to quantify the health and economic benefits of optimizing both serum potassium levels and RAASi therapy in heart failure patients. Analyses were conducted using a UK payer perspective, independent of costs and utilities related to pharmacological potassium management. RESULTS: Validation against multiple datasets demonstrated the predictive capability of the model. Compared to those who discontinued RAASi to manage serum potassium, patients with normokalemia and ongoing RAASi therapy benefited from longer life expectancy (+1.38 years), per-patient quality-adjusted life year gains (+0.53 QALYs), cost savings (£110), and associated net monetary benefit (£10,679 at £20,000 per QALY gained) over a lifetime horizon. The predicted value of sustained potassium management and ongoing RAASi treatment was largely driven by reduced mortality and hospitalization risks associated with optimal RAASi therapy. LIMITATIONS: Several modeling assumptions were made to account for a current paucity of published literature; however, ongoing refinement and validation of the model will ensure its continued accuracy as the clinical landscape of hyperkalemia evolves. CONCLUSIONS: Predictions generated by this novel modeling approach highlight the value of sustained potassium management to avoid hyperkalemia, enable RAASi therapy, and improve long-term health economic outcomes in patients with heart failure.


Assuntos
Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Insuficiência Cardíaca/tratamento farmacológico , Hiperpotassemia/induzido quimicamente , Hiperpotassemia/economia , Potássio/sangue , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Análise Custo-Benefício , Progressão da Doença , Gastos em Saúde/estatística & dados numéricos , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Humanos , Hiperpotassemia/mortalidade , Hiperpotassemia/prevenção & controle , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida , Fatores de Tempo
13.
Nat Commun ; 9(1): 2107, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844417

RESUMO

The detailed analysis of magnetic interactions in a giant molecule is difficult both because the synthesis of such compounds is challenging and the number of energy levels increases exponentially with the magnitude and number of spins. Here, we isolated a {Ni21Gd20} nanocage with a large number of energy levels (≈5 × 1030) and used quantum Monte Carlo (QMC) simulations to perform a detailed analysis of magnetic interactions. Based on magnetization measurements above 2 K, the QMC simulations predicted very weak ferromagnetic interactions that would give a record S = 91 spin ground state. Low-temperature measurements confirm the spin ground state but suggest a more complex picture due to the single ion anisotropy; this has also been modeled using the QMC approach. The high spin and large number of low-lying states lead to a large low-field magnetic entropy (14.1 J kg-1 K-1 for ΔH = 1 T at 1.1 K) for this material.

14.
Bioresour Technol ; 264: 90-97, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29793118

RESUMO

To determine the feasibility of microalgae-yeast mixed culture using the liquid digestate of dairy wastewater (LDDW) for biofuels and single cell protein (SCP) production, the cell growth, nutrient removal and outputs evaluation of the mono and mixed culture of Chlorella vulgaris and Yarrowia lipolytica in LDDW were investigated by adding glycerol as carbon source. The results showed that the mixed culture could enhance the biological utilization efficiency of nitrogen and phosphorus, and obtain higher yield of biomass (1.62 g/L), lipid (0.31 g/L), protein (0.51 g/L), and higher heating value (34.06 KJ/L). Compared with the mono culture of C. vulgaris, a decline of the transcription level in nitrate reductase and glutamine synthetase II genes in C. vulgaris was observed in the mixed culture when ammonia was sufficient. The results suggest the possibility of using the mixed culture for the efficient treatment of LDDW and resources recycling.


Assuntos
Microalgas , Nitrogênio/metabolismo , Transcrição Gênica , Águas Residuárias , Biocombustíveis , Biomassa , Chlorella vulgaris , Microalgas/genética , Microalgas/metabolismo , Fósforo
15.
Angew Chem Int Ed Engl ; 56(52): 16571-16574, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29076224

RESUMO

Chromium lanthanide heterometallic wheel complexes {Cr8 Ln8 } (Ln=Gd, Dy and Y) with alternating metal centres are presented. Quantum Monte Carlo simulations reveal antiferromagnetic exchange-coupling constants with an average of 2.1 K within the {Cr8 Gd8 } wheel, which leads to a large ground spin state (ST =16) that is confirmed by magnetization studies up to 20 Tesla. The {Cr8 Dy8 } wheel is a single-molecule magnet.

16.
Bioresour Technol ; 245(Pt B): 1507-1519, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28642053

RESUMO

As new feedstock for biofuels, microbial oils have received worldwide attentions due to their environmentally-friendly characters. Microbial oil production based on low-cost raw materials is significantly attractive to the current biodiesel refinery industry. In terms of SCOs production, oleaginous yeast has numerous advantages over bacteria, molds and microalgae based on their high growth rate and lipid yield. Numerous efforts have been made on the competitive lipid production combining the use of cheap raw materials as substrates by yeasts. In this paper, we provided an overview of lipid metabolism in yeast cells. New advances using oleaginous yeast as a cell factory for high-value lipid production from various low-cost substrates are also reviewed, and the enhanced strategies based on synergistic effects of oleaginous yeast and microalgae in co-culture are discussed in details.


Assuntos
Biocombustíveis , Leveduras , Fungos , Lipídeos , Microalgas , Óleos
17.
Neuroradiology ; 59(2): 135-145, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28070598

RESUMO

INTRODUCTION: We describe the imaging findings encountered in GBM patients receiving immune checkpoint blockade and assess the potential of quantitative MRI biomarkers to differentiate patients who derive therapeutic benefit from those who do not. METHODS: A retrospective analysis was performed on longitudinal MRIs obtained on recurrent GBM patients enrolled on clinical trials. Among 10 patients with analyzable data, bidirectional diameters were measured on contrast enhanced T1 (pGd-T1WI) and volumes of interest (VOI) representing measurable abnormality suggestive of tumor were selected on pGdT1WI (pGdT1 VOI), FLAIR-T2WI (FLAIR VOI), and ADC maps. Intermediate ADC (IADC) VOI represented voxels within the FLAIR VOI having ADC in the range of highly cellular tumor (0.7-1.1 × 10-3 mm2/s) (IADC VOI). Therapeutic benefit was determined by tissue pathology and survival on trial. IADC VOI, pGdT1 VOI, FLAIR VOI, and RANO assessment results were correlated with patient benefit. RESULTS: Five patients were deemed to have received therapeutic benefit and the other five patients did not. The average time on trial for the benefit group was 194 days, as compared to 81 days for the no benefit group. IADC VOI correlated well with the presence or absence of clinical benefit in 10 patients. Furthermore, pGd VOI, FLAIR VOI, and RANO assessment correlated less well with response. CONCLUSION: MRI reveals an initial increase in volumes of abnormal tissue with contrast enhancement, edema, and intermediate ADC suggesting hypercellularity within the first 0-6 months of immunotherapy. Subsequent stabilization and improvement in IADC VOI appear to better predict ultimate therapeutic benefit from these agents than conventional imaging.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Glioblastoma/diagnóstico por imagem , Glioblastoma/terapia , Imunoterapia/métodos , Imageamento por Ressonância Magnética/métodos , Biomarcadores Tumorais , Neoplasias Encefálicas/patologia , Meios de Contraste , Feminino , Glioblastoma/patologia , Humanos , Interpretação de Imagem Assistida por Computador , Ipilimumab , Masculino , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Nivolumabe , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
18.
Diabetes Obes Metab ; 19(5): 628-634, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28026908

RESUMO

AIMS: Time-dependent HbA1c trajectories in health economic models of type 2 diabetes mellitus (T2DM) are typically informed by the UK Prospective Diabetes Study (UKPDS). However, this approach may not accurately predict HbA1c progression in patients who do not conform to the demographic profile of the original UKPDS cohort. This study aimed to develop an alternative mathematical model (MM) to simulate HbA1c progression in T2DM. MATERIALS AND METHODS: A systematic literature review identified studies, published between 2005 and 2015, that reported HbA1c in adult T2DM patients over a minimum duration of 18 months. Pooled data from eligible studies were used to develop an alternative MM equation for HbA1c progression, which was then contrasted with the UKPDS 68 progression equation in illustrative scenarios. RESULTS: A total of 68 studies were eligible for data extraction (mean follow-up time 4.1 years). HbA1c progression was highly heterogeneous across studies, varying with baseline HbA1c, treatment group and patient age. The MM equation was fitted with parameters for mean baseline HbA1c (8.3%), initial change in HbA1c (-0.62%) and upper quartile of maximum observed HbA1c (9.3%). Differences in HbA1c trajectories between the MM and UKPDS approaches altered the timing of therapy escalation in illustrative scenarios. CONCLUSIONS: The MM represents an alternative approach to simulate HbA1c trajectories in T2DM models, as UKPDS data may not adequately reflect the heterogeneity of HbA1c profiles observed in clinical studies. However, the choice of approach should ultimately be determined by the characteristics of individual patients under consideration and the clinical face validity of the modelled trajectories.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Economia Médica , Medicina Baseada em Evidências , Hemoglobinas Glicadas/análise , Hiperglicemia/prevenção & controle , Hipoglicemia/prevenção & controle , Modelos Biológicos , Terapia Combinada/efeitos adversos , Simulação por Computador , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta para Diabéticos , Progressão da Doença , Monitoramento de Medicamentos , Quimioterapia Combinada/efeitos adversos , Feminino , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto
19.
Microb Cell Fact ; 15(1): 151, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27585813

RESUMO

BACKGROUND: The conversion of cellulose by cellulase to fermentable sugars for biomass-based products such as cellulosic biofuels, biobased fine chemicals and medicines is an environment-friendly and sustainable process, making wastes profitable and bringing economic benefits. Trichoderma reesei is the well-known major workhorse for cellulase production in industry, but the low ß-glucosidase activity in T. reesei cellulase leads to inefficiency in biomass degradation and limits its industrial application. Thus, there are ongoing interests in research to develop methods to overcome this insufficiency. Moreover, although ß-glucosidases have been demonstrated to influence cellulase production and participate in the regulation of cellulase production, the underlying mechanism remains unclear. RESULTS: The T. reesei recombinant strain TRB1 was constructed from T. reesei RUT-C30 by the T-DNA-based mutagenesis. Compared to RUT-C30, TRB1 displays a significant enhancement of extracellular ß-glucosidase (BGL1) activity with 17-fold increase, a moderate increase of both the endoglucanase (EG) activity and the exoglucanase (CBH) activity, a minor improvement of the total filter paper activity, and a faster cellulase induction. This superiority of TRB1 over RUT-C30 is independent on carbon sources and improves the saccharification ability of TRB1 cellulase on pretreated corn stover. Furthermore, TRB1 shows better resistance to carbon catabolite repression than RUT-C30. Secretome characterization of TRB1 shows that the amount of CBH, EG and BGL in the supernatant of T. reesei TRB1 was indeed increased along with the enhanced activities of these three enzymes. Surprisingly, qRT-PCR and gene cloning showed that in TRB1 ß-glucosidase cel3D was mutated through the random insertion by AMT and was not expressed. CONCLUSIONS: The T. reesei recombinant strain TRB1 constructed in this study is more desirable for industrial application than the parental strain RUT-C30, showing extracellular ß-glucosidase hyper production, high cellulase production within a shorter time and a better resistance to carbon catabolite repression. Disruption of ß-glucosidase cel3D in TRB1 was identified, which might contribute to the superiority of TRB1 over RUT-C30 and might play a role in the cellulase production. These results laid a foundation for future investigations to further improve cellulase enzymatic efficiency and reduce cost for T. reesei cellulase production.


Assuntos
Celulase/biossíntese , Trichoderma/genética , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , Biomassa , Carbono/metabolismo , Repressão Catabólica/genética , Celulase/economia , Clonagem Molecular , DNA Bacteriano , Fermentação , Microbiologia Industrial/métodos , Mutagênese , Mutação , Reação em Cadeia da Polimerase em Tempo Real , Trichoderma/enzimologia , Trichoderma/metabolismo
20.
Clinicoecon Outcomes Res ; 8: 275-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27366099

RESUMO

Invasive fungal infections (IFIs) require rapid diagnosis and treatment. A decision-analytic model was used to estimate total costs and survival associated with a diagnostic-driven (DD) or an empiric treatment approach in neutropenic patients with hematological malignancies receiving chemotherapy or autologous/allogeneic stem cell transplants in Shanghai, Beijing, Chengdu, and Guangzhou, the People's Republic of China. Treatment initiation for the empiric approach occurred after clinical suspicion of an IFI; treatment initiation for the DD approach occurred after clinical suspicion and a positive IFI diagnostic test result. Model inputs were obtained from the literature; treatment patterns and resource use were based on clinical opinion. Total costs were lower for the DD versus the empiric approach in Shanghai (¥3,232 vs ¥4,331), Beijing (¥3,894 vs ¥4,864), Chengdu, (¥4,632 vs ¥5,795), and Guangzhou (¥8,489 vs ¥9,795). Antifungal administration was lower using the DD (5.7%) than empiric (9.8%) approach, with similar survival rates. Results from one-way and probabilistic sensitivity analyses were most sensitive to changes in diagnostic test sensitivity and IFI incidence; the DD approach dominated the empiric approach in 88% of scenarios. These results suggest that a DD compared to an empiric treatment approach in the People's Republic of China may be cost saving, with similar overall survival in immunocompromised patients with suspected IFIs.

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