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1.
Chromosome Res ; 30(4): 309-333, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36208359

RESUMEN

Homomorphic sex chromosomes and their turnover are common in teleosts. We investigated the evolution of nascent sex chromosomes in several populations of two sister species of African annual killifishes, Nothobranchius furzeri and N. kadleci, focusing on their under-studied repetitive landscape. We combined bioinformatic analyses of the repeatome with molecular cytogenetic techniques, including comparative genomic hybridization, fluorescence in situ hybridization with satellite sequences, ribosomal RNA genes (rDNA) and bacterial artificial chromosomes (BACs), and immunostaining of SYCP3 and MLH1 proteins to mark lateral elements of synaptonemal complexes and recombination sites, respectively. Both species share the same heteromorphic XY sex chromosome system, which thus evolved prior to their divergence. This was corroborated by sequence analysis of a putative master sex determining (MSD) gene gdf6Y in both species. Based on their divergence, differentiation of the XY sex chromosome pair started approximately 2 million years ago. In all populations, the gdf6Y gene mapped within a region rich in satellite DNA on the Y chromosome long arms. Despite their heteromorphism, X and Y chromosomes mostly pair regularly in meiosis, implying synaptic adjustment. In N. kadleci, Y-linked paracentric inversions like those previously reported in N. furzeri were detected. An inversion involving the MSD gene may suppress occasional recombination in the region, which we otherwise evidenced in the N. furzeri population MZCS-121 of the Limpopo clade lacking this inversion. Y chromosome centromeric repeats were reduced compared with the X chromosome and autosomes, which points to a role of relaxed meiotic drive in shaping the Y chromosome repeat landscape. We speculate that the recombination rate between sex chromosomes was reduced due to heterochiasmy. The observed differences between the repeat accumulations on the X and Y chromosomes probably result from high repeat turnover and may not relate closely to the divergence inferred from earlier SNP analyses.


Asunto(s)
Fundulidae , Peces Killi , Animales , Humanos , Peces Killi/genética , Fundulidae/genética , Hibridación Fluorescente in Situ , Hibridación Genómica Comparativa , Cromosomas Sexuales/genética , Cromosoma Y/genética , Pueblo Africano , Evolución Molecular
2.
Mol Phylogenet Evol ; 148: 106806, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32247884

RESUMEN

Western Southeast Asia is hosting one of the world's most diverse faunas, and one of the reasons for this huge diversity is the complex geologic past of the area, increasing the frequency of isolation and expansion events over evolutionary time scale. As an example case, the present study reveals the phylogeny and biogeographic history of the Paracanthocobitis zonalternans species complex, small benthic freshwater fish (Teleostei: Nemacheilidae) that are commonly occurring across western Southeast Asia (from central Myanmar through western and southern Thailand to northern Malaysia). The group is particularly interesting since it occurs in three biogeographic subdivisions (Indian, Indochinese, Malay/Sundaic) and across all of the major biogeographic barriers in the region. Basing on mitochondrial and nuclear sequence data of 93 samples from about 50 localities we found six major clades, most with exclusive geographic distribution. Divergence time dated the origin of the P. zonalternans species complex to early Miocene (17.8 MYA) and a biogeographic analysis identified the Tenasserim region as the ancestral region. From this region the fish spread during periods of lowered global sea level, particularly during late Miocene (11-8 MYA) northwards into all Burmese river basins and southwards into south Thailand and northern Malaysia. Besides lowered global sea level periods, local stream capture events allowed the complex to expand, e.g. into the Mae Klong basin. Strong fragmentations during periods with elevated sea level during the Pliocene and Pleistocene repeatedly restricted populations to refuges and shaped the observed major lineages. Our results document a higher diversity within the P. zonalternans species complex than formerly believed and a strong impact of global sea level on its evolutionary history. Low sea levels promoted dispersal and elevated sea levels fragmentation events. A very similar impact of sea level changes can be expected in all stationary fauna (freshwater and terrestrial) in all non-mountainous coastal regions worldwide.


Asunto(s)
Biodiversidad , Biota , Cipriniformes/fisiología , Agua Dulce , Filogeografía , Agua de Mar , Animales , Asia Sudoriental , Teorema de Bayes , ADN Mitocondrial/genética , Geografía , Filogenia , Factores de Tiempo
3.
Mol Phylogenet Evol ; 151: 106894, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32562824

RESUMEN

The Schistura robertsi species complex is a group of freshwater fish inhabiting streams in southeast Myanmar as well as in western and southern Thailand. In southern Thailand, the distribution exceeds the biogeographically important 'Surat Thani - Krabi line'. The complex is believed to include five described and one undescribed species, but monophyly and systematics of the group have never been studied explicitly. The present study aims to resolve the number of species within the Schistura robertsi group as well as their distribution areas and phylogenetic relations. We analysed mitochondrial and nuclear sequence data of 86 specimens from 47 localities and 18 morphological characters of 193 specimens. The phylogenetic analyses revealed the S. robertsi complex to be monophyletic and to be composed of ten major lineages. Six of them correspond to the known described or undescribed species, but another four newly identified clades reveal the existence of an overlooked diversity within the group. All genetic lineages are statistically highly supported and all are morphologically diagnosable, suggesting that they represent distinct species. The distribution areas of several clades overlap, the cases of direct co-occurrence show no sign of hybridisation.


Asunto(s)
Biodiversidad , Cipriniformes/anatomía & histología , Cipriniformes/clasificación , Animales , Teorema de Bayes , Calibración , Geografía , Mianmar , Filogenia , Especificidad de la Especie , Tailandia , Factores de Tiempo
4.
Cancer ; 122(18): 2886-94, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27305037

RESUMEN

BACKGROUND: The authors compared longitudinal patient-reported outcomes and physician-rated cosmesis with conventionally fractionated whole-breast irradiation (CF-WBI) versus hypofractionated whole-breast irradiation (HF-WBI) within the context of a randomized trial. METHODS: From 2011 to 2014, a total of 287 women with American Joint Committee on Cancer stage 0 to stage II breast cancer were randomized to receive CF-WBI (at a dose of 50 grays in 25 fractions plus a tumor bed boost) or HF-WBI (at a dose of 42.56 grays in 16 fractions plus a tumor bed boost) after breast-conserving surgery. Patient-reported outcomes were assessed using the Breast Cancer Treatment Outcome Scale (BCTOS), the Functional Assessment of Cancer Therapy-Breast, and the Body Image Scale and were recorded at baseline and 0.5, 1, 2, and 3 years after radiotherapy. Physician-rated cosmesis was assessed at the same time points. Outcomes by treatment arm were compared at each time point using a 2-sided Student t test. Multivariable mixed effects growth curve models assessed the effects of treatment arm and time on longitudinal outcomes. RESULTS: Of the 287 patients enrolled, 149 were randomized to CF-WBI and 138 were randomized to HF-WBI. At 2 years, the Functional Assessment of Cancer Therapy-Breast Trial Outcome Index score was found to be modestly better in the HF-WBI arm (mean 79.6 vs 75.9 for CF-WBI; P = .02). In multivariable mixed effects models, treatment arm was not found to be associated with longitudinal outcomes after adjusting for time and baseline outcome measures (P≥.14). The linear effect of time was significant for BCTOS measures of functional status (P = .001, improved with time) and breast pain (P = .002, improved with time). CONCLUSIONS: In this randomized trial, longitudinal outcomes did not appear to differ by treatment arm. Patient-reported functional and pain outcomes improved over time. These findings are relevant when counseling patients regarding decisions concerning radiotherapy. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2886-2894. © 2016 American Cancer Society.


Asunto(s)
Neoplasias de la Mama/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Medición de Resultados Informados por el Paciente , Radioterapia Adyuvante
5.
Sci Rep ; 13(1): 21131, 2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38036615

RESUMEN

The right choice of an oviposition site is a crucial task for oviparous species without maternal care. In contrast to well investigated biotic factors, e.g., larval food preferences, parasitism, predation, and competition avoiding, abiotic factors affecting oviposition preferences in insects have been rarely investigated in comparative studies. To improve our current understanding of oviposition site selection in Orthoptera, we investigated the influence of substrate temperature and moisture on the oviposition behaviour of 14 temperate grasshopper species. Conspecific groups of adults were kept in arenas with simultaneous temperature and moisture gradients. For each ootheca produced during the experiment (n = 1192) we recorded its depth and local microclimatic conditions. Our results indicate that microclimatic oviposition preferences significantly differ among species, however, correlations between adult habitat preferences and microclimatic oviposition preferences were surprisingly weak. Even oligothermic species preferred substrate temperatures around 30 °C and some xerothermic species preferred higher humidity. The hypothesized tendency to place oothecae closer to the ground within grass tussocks under hot and dry conditions was confirmed. It is possible that species evaluate microclimatic conditions for oviposition in the context of occupied habitat, i.e., in a relative rather than absolute manner.


Asunto(s)
Escarabajos , Saltamontes , Femenino , Animales , Temperatura , Humedad , Oviposición/fisiología , Larva
6.
Sci Rep ; 13(1): 16996, 2023 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-37813885

RESUMEN

To approach the taxonomy of large and complex animal groups it is of advantage to focus on species groups with shared derived character state. We investigate the composition, morphological characteristics and relationships of and within the Schistura cincticauda species group, whose members are small freshwater fishes that inhabit streams and rivers in eastern Myanmar and western and southern Thailand. A phylogenetic analysis using molecular genetic markers demonstrated the monophyly of this group; a combined genetic and morphological analysis revealed the inclusion of at least twelve species. They share the presence of a pair of black marks on the lower lip, one on each side of the median interruption (these marks may be reduced to few melanophores or even missing in some individuals). Additionally, all species share a small body size (max. 60 mm SL), an incomplete lateral line reaching at most to vertical through anal-fin base, and the absence of sexual dimorphism. Each of the 12 species is diagnosed by a unique combination of character states in fin ray numbers, anus position, presence/absence of an axillary pelvic lobe, and colour pattern. The distribution areas of several species overlap and five cases of syntopic occurrence are known. Five unnamed species are described herein.


Asunto(s)
Cipriniformes , Humanos , Animales , Filogenia , Ríos , Tamaño Corporal , Caracteres Sexuales
7.
Artículo en Inglés | MEDLINE | ID: mdl-37114105

RESUMEN

Introduction: Recently, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) has published an update on the Global Strategy for Prevention, Diagnosis and Management of COPD, introducing a new classification of chronic obstructive pulmonary disease (COPD). Our aim was to assess the prognostic value of the new GOLD classification system in comparison with the previous GOLD classification systems (GOLD stages I-IV and GOLD groups A-D) and the BODE index. Methods: We used the data of 784 patients with COPD from the Czech Multicenter Research Database of COPD. Patient survival was analyzed with the use of Kaplan-Meier estimate and Cox model of proportional risks. ROC analysis and area under curve (AUC) were used for comparison of GOLD classifications and BODE index. The analyses were performed with the use of software R (version 4.2.0). Results: We analyzed data of 782 patients with complete data on GOLD classifications. The study population comprised 72.9% of men, 89.1% current or former smokers, with a mean age of 66.6 years, a mean BMI of 27.4 and a mean FEV1 44.9% of predicted. Probability of 5-year survival differed by GOLD classification. Application of the 2023 GOLD classification showed increased risk of death in group B (HR 1.82, 95% CI 1.14-2.92; p = 0.013) and in group E (HR 2.48, 95% CI 1.54-3.99; p˂0.001). The ROC analysis showed that the overall prognostic value of the 2023 GOLD classification was similarly weak to previous A-D GOLD classification schemes (AUCs 0.557-0.576) and was lower compared to the GOLD 1-4 system (AUC 0.614) and even lower when compared to the BODE index (AUC 0.715). Conclusion: We concluded that the new GOLD classification system has poor prognostic properties and that specific prediction tools (eg, the BODE index) should be used for mortality risk assessment.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Masculino , Humanos , Anciano , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/terapia , Progresión de la Enfermedad , Medición de Riesgo , Modelos de Riesgos Proporcionales , Índice de Severidad de la Enfermedad
8.
Int J Radiat Oncol Biol Phys ; 117(1): 22-30, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37244624

RESUMEN

PURPOSE: There is increasing concern about rising carbon dioxide (CO2) emissions and their hazardous effect on human health. This study quantifies the energy utilization of proton therapy, assesses the corresponding carbon footprint, and discusses possible offsetting strategies toward carbon-neutral health care operations. METHODS AND MATERIALS: Patients treated between July 2020 and June 2021 using the Mevion proton system were evaluated. Current measurements were converted to kilowatts of power consumption. Patients were reviewed for disease, dose, number of fractions, and duration of beam. The Environmental Protection Agency calculator was used to convert power consumption to tons of CO2 equivalent (CO2e) for scope-based carbon footprint accounting. RESULTS: There were 185 patients treated and a total of 5176 fractions delivered (average, 28). Power consumption was 55.8 kW in standby/night mode and 64.4 kW during BeamOn, for an annual total of 490 MWh. BeamOn time was 149.6 hours, and BeamOn consumption accounted for 2% of the machine total. Power consumption was 52 kWh per patient (breast, highest at 140 kWh; prostate, lowest at 28 kWh). Annual power consumption of the administrative areas was approximately 96 MWh, for a program total of 586 MWh. The carbon footprint for BeamOn time was 4.17 metric tons of CO2e, or 23 kg per patient course (breast cancer, 60 kg; prostate, 12 kg). The annual carbon footprint for the machine was 212.2 tons CO2e, and for the proton program, 253.7 tons CO2e, with an attributed footprint of 1372 kg CO2e per patient. The corresponding CO2e offset for the program could be 4192 new trees planted and grown for 10 years (23 trees per patient). CONCLUSIONS: The carbon footprint varied by disease treated. On average, the carbon footprint was 23 kg of CO2e per patient and 253.7 tons of CO2e for the proton program. There are a number of reduction, mitigation, and offset strategies possible for radiation oncologists that should be explored, such as waste minimization, less treatment commuting, efficient energy use, and renewable electricity power use.


Asunto(s)
Terapia de Protones , Estados Unidos , Masculino , Humanos , Protones , Dióxido de Carbono , Huella de Carbono , Mama
9.
Int J Part Ther ; 10(2): 85-93, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38075486

RESUMEN

Purpose: Many patients with metastatic cancer live years beyond diagnosis, and there remains a need to improve the therapeutic ratio of metastasis-directed radiation for these patients. This study aimed to assess a process for delivering cost-effective palliative proton therapy to the spine using diagnostic scan-based planning (DSBP) and prefabricated treatment delivery devices. Materials and Methods: We designed and characterized a reusable proton aperture system that adjusts to multiple lengths for spine treatment. Next, we retrospectively identified 10 patients scan treated with thoracic proton therapy who also had a diagnostic computed tomography within 4 months of simulation. We contoured a T6-T9 target volume on both the diagnostic scans (DS) and simulation scans (SS). Using the aperture system, we generated proton plans on the DS using a posterior-anterior beam with no custom range compensator to treat T6-T9 to 8 Gy × 1. Plans were transferred to the SS to compare coverage and normal tissue doses, followed by robustness analysis. Finally, we compared normal tissue doses and costs between proton and photon plans. Results were compared using the Wilcoxon signed-rank test. Results: Median D95% on the DS plans was 101% (range, 100%-102%) of the prescription dose. Median Dmax was 107% (range, 105%-108%). When transferred to SS, coverage and hot spots remained acceptable for all cases. Heart and esophagus doses did not vary between the DS and SS proton plans (P >.2). Robustness analysis with 5 mm X/Y/Z shifts showed acceptable coverage (D95% > 98%) for all cases. Compared with the proton plans, the mean heart dose was higher for both anterior-posterior/posterior-anterior and volumetric modulated arc therapy plans (P < .01). Cost for proton DSBP was comparable to more commonly used photon regimens. Conclusion: Proton DSBP is technically feasible and robust, with superior sparing of the heart compared with photons. Eliminating simulation and custom devices increases the value of this approach in carefully selected patients.

10.
Ann Intern Med ; 155(3): 171-8, 2011 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-21646550

RESUMEN

BACKGROUND: Radiation therapy is one of many treatment options for patients with prostate cancer. PURPOSE: To update findings on the clinical and biochemical outcomes of radiation therapies for localized prostate cancer. DATA SOURCES: MEDLINE (2007 through March 2011) and the Cochrane Central Register of Controlled Trials (2007 through March 2011). STUDY SELECTION: Published English-language comparative studies involving adults with localized prostate cancer who either had first-line radiation therapy or received no initial treatment. DATA EXTRACTION: 6 researchers extracted information on study design, potential bias, sample characteristics, interventions, and outcomes and rated the strength of overall evidence. Data for each study were extracted by 1 reviewer and confirmed by another. DATA SYNTHESIS: 75 studies (10 randomized, controlled trials [RCTs] and 65 nonrandomized studies) met the inclusion criteria. No RCTs compared radiation therapy with no treatment or no initial treatment. Among the 10 RCTs, 2 compared combinations of radiation therapies, 7 compared doses and fraction sizes of external-beam radiation therapy (EBRT), and 1 compared forms of low-dose rate radiation therapy. Heterogeneous outcomes were analyzed. Overall, moderate-strength evidence consistently showed that a higher EBRT dose was associated with increased rates of long-term biochemical control compared with lower EBRT dose. The body of evidence was rated as insufficient for all other comparisons. LIMITATIONS: Studies inconsistently defined and reported outcomes. Much of the available evidence comes from observational studies with treatment selection biases. CONCLUSION: A lack of high-quality comparative evidence precludes conclusions about the efficacy of radiation treatments compared with no treatments for localized prostate cancer. PRIMARY FUNDING SOURCE: Agency for Healthcare Research and Quality.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Braquiterapia/efectos adversos , Investigación sobre la Eficacia Comparativa , Humanos , Enfermedades Intestinales/etiología , Masculino , Recurrencia Local de Neoplasia , Neoplasias de la Próstata/patología , Radioterapia/efectos adversos , Dosificación Radioterapéutica , Ensayos Clínicos Controlados Aleatorios como Asunto , Disfunciones Sexuales Fisiológicas/etiología , Análisis de Supervivencia , Resultado del Tratamiento , Enfermedades Urológicas/etiología
11.
Biology (Basel) ; 11(2)2022 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-35205042

RESUMEN

Large animal families with unresolved taxonomy are notoriously difficult to handle with respect to their biodiversity, systematics, and evolutionary history. We approach a large and taxonomically unresolved family of freshwater fishes (Nemacheilidae, >600 species) by proposing, on the basis of morphologic data, a species group within the family and study its phylogeny with conclusions regarding its diversity, taxonomy, and biogeographic history. Phylogenetic analyses of two mitochondrial and three nuclear genes of 139 specimens, representing about 46 species (17 candidate species from the proposed species-group, plus 29 comparative species), revealed that the proposed species group does not form a distinct monophyletic lineage, but that the candidate and comparative species mixed in three different lineages. However, the results revealed more than 20% of undescribed species within the ingroup and showed that species do not cluster according to the presently recognised genera. At least one of the genetic clades shows signs of an eastward range expansion during the second half of Miocene from north India via Myanmar into Laos, western China, and western Thailand. We conclude that the approach of picking monophyletic lineages to study biodiversity, systematics, and evolutionary history helps to open the door to large animal families.

12.
Front Pharmacol ; 13: 860270, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034870

RESUMEN

Background: Adherence to inhaled medication constitutes a major problem in patients with chronic obstructive pulmonary disease (COPD) globally. However, large studies evaluating adherence in its entirety and capturing a large variety of potentially associated factors are still lacking. Objective: To study both elementary types of adherence to chronic inhaled COPD medication in "real-life" COPD patients and to assess relationships with a wide-ranging spectrum of clinical parameters. Methods: Data from the Czech Multicentre Research Database (CMRD) of COPD, an observational prospective study, were used. Overall adherence (OA) was evaluated with Morisky Medication Adherence Scale (©MMAS-4) and adherence to an application technique (A-ApplT) with the Five Steps Assessment. Mann-Whitney U test, Spearman's correlation, and logistic regression were used to explore relationships between variables. Results: Data of 546 participants (69.6% of all patients from the CMRD) were analyzed. Two-thirds self-reported optimal OA, but only less than one-third demonstrated A-ApplT without any error. OA did not correlate with A-ApplT. Next, better OA was associated with higher education, a higher number of inhalers, a lower rate of exacerbations, poorer lung function, higher degree of upper respiratory tract symptoms (SNOT-22), absence of depressive symptoms, ex-smoking status, regular mouthwash after inhaled corticosteroids (ICS), and flu vaccination. By contrast, better A-ApplT was associated with a lower number of inhalers, better lung function, and regular mouthwash after ICS. Independent predictors of nonoptimal OA included lower degree of education, absence of flu vaccination, anemia, depression, and peptic ulcer history, whereas independent predictors of lower A-ApplT were lower education, absence of regular mouthwash after ICS, and higher COPD Assessment Test score. Conclusions: Parameters associated with OA and A-ApplT differ, and those associated with both adherence domains are sometimes associated inversely. Based on this finding, we understand these as two separate constructs with an overlap.

13.
Materials (Basel) ; 14(13)2021 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-34209607

RESUMEN

Among different promising solutions, coupling closed-cell aluminium foam composite panels prepared by a powder metallurgical method with pore walls interconnected by microcracks, with low thermal conductivity phase change materials (PCMs), is one of the effective ways of increasing thermal conductivity for better performance of thermal storage systems in buildings. The internal structure of the foam formation, related to the porosity which decides the heat transfer rate, plays a significant role in the thermal energy storage performance. The dependence of the heat transfer characteristics on the internal foam structure is studied numerically in this work. The foamable precursor of 99.7% pure aluminium powder mixed with 0.15 wt.% of foaming agent, TiH2 powder, was prepared by compacting, and extruded to a volume of 20 × 40 × 5 mm. Two aluminium foam samples of 40 × 40 × 5 mm were examined with apparent densities of 0.7415 g/cm3 and 1.62375 g/cm3. The internal porous structure of the aluminium foam samples was modelled using X-ray tomography slices through image processing techniques for finite element analysis. The obtained numerical results for the heat transfer rate and effective thermal conductivity of the developed surrogate models revealed the influence of porosity, struts, and the presence of pore walls in determining the heat flow in the internal structure of the foam. Additionally, it was found that the pore size and its distribution determine the uniform heat flow rate in the entire foamed structure. The numerical data were then validated against the analytical predictions of thermal conductivity based on various correlations. It has been found that the simplified models of Bruggemann and Russell and the parallel-series model can predict the excellent effective thermal conductivity results of the foam throughout the porosity range. The optimal internal foam structure was studied to explore the possibilities of using aluminium foam for PCM-based thermal storage applications.

14.
JCO Oncol Pract ; 17(12): e1949-e1957, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34460290

RESUMEN

PURPOSE: An episode-based payment model, the Radiation Oncology Alternative Payment Model (RO-APM), is scheduled to go into effect in January 2022. This article investigates the effects of RO-APM on hospital-based and freestanding community centers. METHODS: Historical Medicare data used to generate the RO-APM base rates were reviewed. A sensitivity analysis was performed to show how the RO-APM reimbursements compare with current reimbursements for commonly accepted treatment schedules and with current reimbursements at a large community practice. RESULTS: The RO-APM base rates represent a 2.2% decrease in overall Medicare reimbursement. Freestanding centers have historically billed at higher rates than hospital-based centers, however, and the RO-APM base rates represent a 6% decrease in global reimbursement for freestanding centers. The sensitivity analysis showed that, except for proton therapy, moderately hypofractionated treatment schedules will receive comparable reimbursement under RO-APM. Treatments using higher numbers of fractions of intensity-modulated radiation therapy or protons will see larger decreases in reimbursement. Application of the RO-APM base rates to the 2020 Medicare treatments in our health care network would result in small changes in expected reimbursement, but our sensitivity analysis indicated that Medicare reimbursement reductions could be as large as 23%. CONCLUSION: Compared with historical Medicare reimbursement, RO-APM base rates provide lower reimbursement for many common treatment scenarios, and this will have a larger effect on centers that use complex treatment techniques and longer fractionation schedules or have a large Medicare population.


Asunto(s)
Neoplasias , Oncología por Radiación , Anciano , Atención a la Salud , Humanos , Oncología Médica , Medicare , Neoplasias/radioterapia , Estados Unidos
15.
Int J Chron Obstruct Pulmon Dis ; 16: 1171-1182, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33953554

RESUMEN

INTRODUCTION: The concept of phenotyping emerged, reflecting specific clinical, pulmonary and extrapulmonary features of each particular chronic obstructive pulmonary disease (COPD) case. Our aim was to analyze prognostic utility of: "Czech" COPD phenotypes and their most frequent combinations, "Spanish" phenotypes and Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages + groups in relation to long-term mortality risk. METHODS: Data were extracted from the Czech Multicenter Research Database (CMRD) of COPD. Kaplan-Meier (KM) estimates (at 60 months from inclusion) were used for mortality assessment. Survival rates were calculated for the six elementary "Czech" phenotypes and their most frequent and relevant combinations, "Spanish" phenotypes, GOLD grades and groups. Statistically significant differences were tested by Log Rank test. An analysis of factors underlying mortality risk (the role of confounders) has been assessed with the use of classification and regression tree (CART) analysis. Basic factors showing significant differences between deceased and living patients were entered into the CART model. This showed six different risk groups, the differences in risk were tested by a Log Rank test. RESULTS: The cohort (n=720) was 73.1% men, with a mean age of 66.6 years and mean FEV1 44.4% pred. KM estimates showed bronchiectases/COPD overlap (HR 1.425, p=0.045), frequent exacerbator (HR 1.58, p<0.001), cachexia (HR 2.262, p<0.001) and emphysematous (HR 1.786, p=0.015) phenotypes associated with higher mortality risk. Co-presence of multiple phenotypes in a single patient had additive effect on risk; combination of emphysema, cachexia and frequent exacerbations translated into poorest prognosis (HR 3.075; p<0.001). Of the "Spanish" phenotypes, AE CB and AE non-CB were associated with greater risk of mortality (HR 1.787 and 2.001; both p=0.001). FEV1% pred., cachexia and chronic heart failure in patient history were the major underlying factors determining mortality risk in our cohort. CONCLUSION: Certain phenotypes ("Czech" or "Spanish") of COPD are associated with higher risk of death. Co-presence of multiple phenotypes (emphysematous plus cachectic plus frequent exacerbator) in a single individual was associated with amplified risk of mortality.


Asunto(s)
Bronquitis Crónica , Enfermedad Pulmonar Obstructiva Crónica , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Fenotipo , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , España
16.
JCO Oncol Pract ; 17(12): e1943-e1948, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33170747

RESUMEN

PURPOSE: An episode-based payment model, the Radiation Oncology Alternative Payment Model (RO-APM), has been proposed for Medicare reimbursement of radiation services provided to oncology patients. RO-APM may have significant impact on reimbursement for specific patient populations. METHODS: This investigation compares historical fee-for-service technical reimbursement estimates at a large hospital-based system to the RO-APM for advanced radiotherapy treatment of specific cancer types. These advanced techniques, stereotactic radiosurgery (SRS), stereotactic body radiotherapy (SBRT), online-adaptive SBRT, and proton therapy, were specifically chosen because they are resource intensive and are correspondingly among the most expensive radiation oncology procedures. A total of 203 Medicare patients were analyzed. RESULTS: RO-APM base-rate reimbursements were similar for SRS and were 38%-47% higher for SBRT. The proposed rates were 1%-31% lower for online-adaptive SBRT, and 48%-71% lower for proton therapy. CONCLUSION: These data suggest that the RO-APM may have the desired effect of encouraging shorter courses of radiotherapy, such as SBRT. However, emerging technologies that require large capital and operating investments may see an overall significant reduction in proposed reimbursement.


Asunto(s)
Neoplasias , Terapia de Protones , Oncología por Radiación , Radiocirugia , Anciano , Humanos , Medicare , Neoplasias/radioterapia , Estados Unidos
17.
Int J Radiat Oncol Biol Phys ; 111(2): 360-370, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33992718

RESUMEN

PURPOSE: There are limited prospective data on predictors of patient-reported outcomes (PROs) after whole-breast irradiation (WBI) plus a boost. We sought to characterize longitudinal PROs and cosmesis in a randomized trial comparing conventionally fractionated (CF) versus hypofractionated (HF) WBI. METHODS AND MATERIALS: From 2011 to 2014, women aged ≥40 years with Tis-T2 N0-N1a M0 breast cancer who underwent a lumpectomy with negative margins were randomized to CF-WBI (50 Gray [Gy]/25 fractions plus boost) versus HF-WBI (42.56 Gy/16 fractions plus boost). At baseline (pre-radiation), at 6 months, and yearly thereafter through 5 years, PROs included the Breast Cancer Treatment Outcome Scale (BCTOS), Functional Assessment of Cancer Therapy-Breast (FACT-B), and Body Image Scale; cosmesis was reported by the treating physician using Radiation Therapy Oncology Group cosmesis values. Multivariable mixed-effects growth curve models evaluated associations of the treatment arm and patient factors with outcomes and tested for relevant interactions with the treatment arm. RESULTS: A total of 287 patients were randomized, completing a total of 14,801 PRO assessments. The median age was 60 years, 37% of patients had a bra cup size ≥D, 44% were obese, and 30% received chemotherapy. Through 5 years, there were no significant differences in PROs or cosmesis by treatment arm. A bra cup size ≥D was associated with worse BCTOS cosmesis (P < .001), BCTOS pain (P = .001), FACT-B Trial Outcome Index (P = .03), FACT-B Emotional Well-being (P = .03), and Body Image Scale (P = .003) scores. Physician-rated cosmesis was worse in patients who were overweight (P = .02) or obese (P < .001). No patient subsets experienced better PROs or cosmesis with CF-WBI. CONCLUSIONS: Both CF-WBI and HF-WBI confer similar longitudinal PROs and physician-rated cosmesis through 5 years of follow-up, with no relevant subsets that fared better with CF-WBI. This evidence supports broad adoption of hypofractionation with boost, including in patients receiving chemotherapy and in a population with a high prevalence of obesity. The associations of large breast size and obesity with adverse outcomes across multiple domains highlight the opportunity to engage at-risk patients in lifestyle intervention strategies, as well as to consider alternative radiation treatment regimens.


Asunto(s)
Neoplasias de la Mama/radioterapia , Mama/efectos de la radiación , Medición de Resultados Informados por el Paciente , Hipofraccionamiento de la Dosis de Radiación , Anciano , Imagen Corporal , Neoplasias de la Mama/psicología , Femenino , Disparidades en el Estado de Salud , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Calidad de Vida
18.
J Neurooncol ; 98(1): 77-82, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19904495

RESUMEN

Given the potential morbidity of whole brain radiation therapy (WBRT), there has been an increasing trend to defer WBRT and deliver Gamma Knife stereotactic radiosurgery (GKS) to cerebral metastatic lesions. We analyzed our experience delivering GKS to the tumor cavity following surgical resection of brain metastases and compared our results to patients receiving WBRT after surgical resection of a metastatic lesion. We performed a retrospective review of patients undergoing surgical resection of at least one brain metastasis between December 1999 and December 2008. Both univariate and multivariate Cox proportional hazards regression were utilized to analyze the influence of various prognostic factors on survival. Twenty-five patients had a metastatic lesion resected followed by adjuvant GKS to the resection cavity while another 18 had surgical resection followed by WBRT. Aside from a disparity in gender distribution (72% of GKS patients were female while women only constituted 28% of the WBRT group), no significant differences existed between groups. The median survival for patients receiving GKS was 15.00 months as compared to 6.81 months among those receiving WBRT (P = 0.08). Univariate Cox regression analysis identified the number of metastases (HR 1.65, 95% CI 1.07-2.54, P = 0.02) and regional recurrence (RR 5.23, 95% CI 1.78-15.38, P = 0.003) as poor prognostic factors. Multivariate regression analysis showed that regional recurrence (HR 5.17, 95% CI 1.69-15.78, P = 0.004) was again strongly associated with worse survival. Although limited by the retrospective nature of our study and lack of some clinical measures, patients undergoing GKS to the resection cavity had a trend towards longer median survival.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/cirugía , Radiocirugia/métodos , Adulto , Anciano , Neoplasias Encefálicas/secundario , Craneotomía/métodos , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
19.
Ann Intern Med ; 151(8): 556-65, 2009 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-19755348

RESUMEN

BACKGROUND: Radiation therapy with charged particles can potentially deliver maximum doses while minimizing irradiation of surrounding tissues, and it may be more effective or less harmful than other forms of radiation therapy. PURPOSE: To review evidence about the benefits and harms of charged-particle radiation therapy for patients with cancer. DATA SOURCES: MEDLINE (inception to 11 July 2009) was searched for publications in English, German, French, Italian, and Japanese. Web sites of manufacturers, treatment centers, and professional organizations were searched for relevant information. STUDY SELECTION: Four reviewers identified studies of any design that described clinical outcomes or adverse events in 10 or more patients with cancer treated with charged-particle radiation therapy. DATA EXTRACTION: The 4 reviewers extracted study, patient, and treatment characteristics; clinical outcomes; and adverse events for nonoverlapping sets of articles. A fifth reviewer verified data on comparative studies. DATA SYNTHESIS: Currently, 7 centers in the United States have facilities for particle (proton)-beam irradiation, and at least 4 are under construction, each costing between $100 and $225 million. In 243 eligible articles, charged-particle radiation therapy was used alone or in combination with other interventions for common (for example, lung, prostate, or breast) or uncommon (for example, skull-base tumors or uveal melanomas) types of cancer. Of 243 articles, 185 were single-group retrospective studies. Eight randomized and 9 nonrandomized clinical trials compared treatments with or without charged particles. No comparative study reported statistically significant or important differences in overall or cancer-specific survival or in total serious adverse events. LIMITATION: Few studies directly compared treatments with or without particle irradiation. CONCLUSION: Evidence on the comparative effectiveness and safety of charged-particle radiation therapy in cancer is needed to assess the benefits, risks, and costs of treatment alternatives.


Asunto(s)
Neoplasias/radioterapia , Radioterapia de Alta Energía/métodos , Braquiterapia , Humanos , Cuidados Intraoperatorios , Radiocirugia , Proyectos de Investigación
20.
Materials (Basel) ; 13(23)2020 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-33260595

RESUMEN

The current study reflects the demand to mitigate the environmental issues caused by the waste from the agriculture and food industry. The crops that do not meet the supply chain requirements and waste from their processing are overfilling landfills. The mentioned wastes contain cellulose, which is the most abundant carbon precursor. Therefore, one of the possibilities of returning such waste into the life cycle could be preparing the activated carbon through an eco-friendly and simple route. Herein, the carrot pulp from the waste was used. Techniques such as thermogravimetric analysis (TGA), elemental analysis (EA), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and x-ray diffraction (XRD) were used to investigate the thermal treatment effect during the carbon material preparation. The development of microstructure, phase formation, and chemical composition of prepared material was evaluated. The obtained carbon material was finally tested for water cleaning from a synthetic pollutant such as rhodamine B and phloxine B. An adsorption mechanism was proposed on the base of positron annihilation lifetime spectroscopy (PALS) results and attributed to the responsible interactions. It was shown that a significant carbon sorbent from the organic waste for water purification was obtained.

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