Farmworker Mobility and COVID-19 Vaccination Strategies: Yuma County, Arizona, 2021.

Farmworkers, a group of essential workers, experience a disproportionately high burden of COVID-19 due to their living and working conditions. This project characterized farmworker mobility in and around Yuma County, Arizona, to identify opportunities to improve farmworker access to COVID-19 vaccination. We collected qualitative and geospatial data through a series of in-person and virtual focus group discussions, key informant interviews, and intercept interviews with participatory mapping. Participants included farmworkers, employers, and representatives of local institutions who serve or interact with farmworkers. We identified participants through purposive and referential sampling and grouped people by sociodemographic characteristics for interviews. We used qualitative and geospatial analyses to identify common themes and mobility patterns. The team interviewed 136 people from February 26 to April 2, 2021. Common themes emerged about how farmworkers have little or no access to COVID-19 vaccination unless offered at their workplaces or at locations where they congregate at convenient times. Further, farmworkers described how their demanding work schedules, long commute times, and caretaker commitments make it challenging to access vaccination services. Geospatial analyses identified three geographic areas in Yuma County where farmworkers reported living and working that did not have a COVID-19 vaccine clinic within walking distance. Coordination between local public health authorities and key partners, including employers and trusted representatives from local community-based organizations or the Mexican consulate, to offer vaccination at worksites or other locations where farmworkers congregate can help improve access to COVID-19 vaccines and booster doses for this population.

Human femur fracture by mechanical compression: Towards the repeatability of bone fracture acquisition.

The increase in life expectancy combined with greater bone fragility over the years is causing a rise in the bone fracture cases. Femur fractures are the most important due to their high mortality rate. This multidisciplinary work is carried out in this context and focuses on the experimental reproduction of human femur fractures by compression. We describe a sequence of steps supervised by orthopaedic surgeons for the correct arrangement of specimens on the system set up to perform the experiment. The device applies force by compression until the human bone is fractured. All tests performed have been monitored and evaluated from different knowledge perspectives. The results obtained have demonstrated the repeatability of the fracture type in a controlled environment as well as identifying the main features involved in this process. In addition, the fractured bones have been digitized to analyze the fracture zone to recreate and evaluate future simulations.

Harmonization of indirect reference intervals calculation by the Bhattacharya method.

OBJECTIVES: The aim of this study was to harmonize the criteria for the Bhattacharya indirect method Microsoft Excel Spreadsheet for reference intervals calculation to reduce between-user variability and use these criteria to calculate and evaluate reference intervals for eight analytes in two different years. METHODS: Anonymized laboratory test results from outpatients were extracted from January 1st 2018 to December 31st 2019. To assure data quality, we examined the monthly results from an external quality control program. Reference intervals were determined by the Bhattacharya method with the St Vincent's hospital Spreadsheet firstly using original criteria and then using additional harmonized criteria defined in this study. Consensus reference intervals using the additional harmonized criteria were calculated as the mean of four users' lower and upper reference interval results. To further test the operation criteria and robustness of the obtained reference intervals, an external user validated the Spreadsheet procedure. RESULTS: The extracted test results for all selected laboratory tests fulfilled the quality criteria and were included in the present study. Differences between users in calculated reference intervals were frequent when using the Spreadsheet. Therefore, additional criteria for the Spreadsheet were proposed and applied by independent users, such as: to set central bin as the mean of all the data, bin size as small as possible, at least three consecutive bins and a high proportion of bins within the curve. CONCLUSIONS: The proposed criteria contributed to the harmonization of reference interval calculation between users of the Bhattacharya indirect method Spreadsheet.

Addressing the contribution of small molecule-based biostimulants to the biofortification of maize in a water restriction scenario.

Biostimulants have become an asset for agriculture since they are a greener alternative to traditionally used plant protection products. Also, they have gained the farmers' acceptance due to their effect on enhancing the plant's natural defense system against abiotic stresses. Besides commercially available complex products, small molecule-based biostimulants are useful for industry and research. Among them, polyamines (PAs) are well-studied natural compounds that can elicit numerous positive responses in drought-stressed plants. However, the studies are merely focused on the vegetative development of the plant. Therefore, we aimed to evaluate how drenching with putrescine (Put) and spermidine (Spd) modified the maize production and the yield quality parameters. First, a dosage optimization was performed, and then the best PA concentrations were applied by drenching the maize plants grown under well-watered (WW) conditions or water deficit (WD). Different mechanisms of action were observed for Put and Spd regarding maize production, including when both PAs similarly improved the water balance of the plants. The application of Put enhanced the quality and quantity of the yield under WW and Spd under WD. Regarding the nutritional quality of the grains, both PAs increased the carbohydrates content, whereas the contribution to the protein content changed by the interaction between compound and growth conditions. The mineral content of the grains was also greatly affected by the water condition and the PA application, with the most relevant results observed when Spd was applied, ending with flour richer in Zn, Cu, and Ca minerals that are considered important for human health. We showed that the exogenous PA application could be a highly efficient biofortification approach. Our findings open a new exciting use to be studied deep in the biostimulant research.

Asclepain cI, a proteolytic enzyme from Asclepias curassavica L., a south American plant, against Helicobacter pylori.

Helicobacter pylori is a Gram negative bacterium most frequently associated with human gastrointestinal infections worldwide. The increasing occurrence of antibiotic-resistant isolates of H. pylori constitutes a challenge. The eradication of the microorganism is currently being considered a "high priority" by the World Health Organization (WHO). In this context, bioactive compounds found in natural products seem to be an effective therapeutic option to develop new antibiotics against the pathogen. In this study, we investigated the effect of asclepain cI, the main purified proteolytic enzyme of the latex of petioles and stems from Asclepia curassavica L. (Asclepiadaceae), a South American native plant, against H. pylori; in order to obtain a natural therapeutic adjuvant and a safe nutraceutical product. Asclepain cI showed antibacterial activity against reference strains and drug-resistant clinical isolates of H. pylori in vitro. A range of minimal inhibitory concentration (MIC) from 1 to 2 µg/ml and minimal bactericidal concentration (MBC) from 2 to 4 µg/ml was obtained, respectively. The action of asclepain cI on the transcription of omp18, ureA, flaA genes showed a significantly decreased expression of the selected pathogenic factors. Furthermore, asclepain cI did not induce toxic effects at the concentrations assayed. Asclepain cI could be considered a highly feasible option to be used as a natural therapeutic adjuvant and a safe nutraceutical product against H. pylori.

Non-ionic surfactant formulation sequentially enhances the enzymatic hydrolysis of cellulignin from sugarcane bagasse and the production of Monascus ruber biopigments.

The effect of a non-ionic surfactant optimized formulation (SOF) obtained from an experimental design was evaluated for different influencing variables in the processing of sugarcane bagasse cellulignin to produce biopigments. The major findings in the saccharification stage using the SOF point that: at same enzyme loading, the highest glucan hydrolysis yield was 63 % (2-fold higher compared to control); the enzyme loading of 2.5 FPU/g resulted in similar yield compared to 10 FPU/g (control); 15 % (m/v) of total solids loading maintained the yield in fed-batch configuration; the hydrolysis yield is maintained at high shear force stress (800 rpm of stirring rate) and temperatures (50-70 °C). Besides, under separate and semi-simultaneous hydrolysis and fermentation, the maximum biopigments production were of 10 AU510nm/mL and 17.84 AU510nm/mL, respectively. The SOF used in this study was found to be a promising additive either in a single or sequential steps to produce biopigments in biorefineries.

Performance evaluation of a point of care cartridge of the new GEM Premier ChemSTAT analyzer.

Background and aims: GEM Premier ChemSTAT is a new point-of-care system providing rapid creatinine, BUN and tCO2 measurements together with electrolytes, metabolites, hematocrit, pH and pCO2 from a single whole blood specimen in acute care settings such as emergency departments and intensive care units. Accurate measurements of whole blood creatinine can aid in the diagnosis and treatment of renal diseases. Materials and methods: Heparinized whole blood samples from different clinical locations were evaluated on the GEM Premier ChemSTAT and results compared to plasma from the same samples on the Beckman AU5800 or whole blood on the GEM Premier 4000. Precision studies were conducted with whole blood and quality control material. Results: ChemSTAT correlated well with plasma samples on the AU5800 (regression slopes (S): 0.957-1.159, correlation coefficients (r)≥0.952) and with whole blood specimens on the GEM Premier 4000 (S: 0.9646-1.124, r ≥ 0.974). The repeatability was 0.1%-3.1% and QC precision were within lab and manufacturers' specifications. Conclusion: ChemSTAT demonstrated strong correlation to the comparative methods and excellent precision. Combining with its continuous quality management, ChemSTAT is suitable for acute care settings to provide rapid, reliable results, which could minimize time-to-treatment and improve patient outcome.

Recent Advances and Potential Applications of Atmospheric Pressure Cold Plasma Technology for Sustainable Food Processing.

In a circular economy, products, waste, and resources are kept in the system as long as possible. This review aims to highlight the importance of cold plasma technology as an alternative solution to some challenges in the food chain, such as the extensive energy demand and the hazardous chemicals used. Atmospheric cold plasma can provide a rich source of reactive gas species such as radicals, excited neutrals, ions, free electrons, and UV light that can be efficiently used for sterilization and decontamination, degrading toxins, and pesticides. Atmospheric cold plasma can also improve the utilization of materials in agriculture and food processing, as well as convert waste into resources. The use of atmospheric cold plasma technology is not without challenges. The wide range of reactive gas species leads to many questions about their safety, active life, and environmental impact. Additionally, the associated regulatory approval process requires significant data demonstrating its efficacy. Cold plasma generation requires a specific reliable system, process control monitoring, scalability, and worker safety protections.

Clinical utility of comprehensive circulating tumor DNA genotyping compared with standard of care tissue testing in patients with newly diagnosed metastatic colorectal cancer.

BACKGROUND: Comprehensive biomarker testing is essential in selecting optimal treatment for patients with metastatic colorectal cancer (mCRC); however, incomplete genotyping is widespread, with most patients not receiving testing for all guideline-recommended biomarkers, in part due to reliance on burdensome sequential tissue-based single-biomarker tests with long waiting times or availability of only archival tissue samples. We aimed to demonstrate that liquid biopsy, associated with rapid turnaround time (TAT) and lower patient burden, effectively identifies guideline-recommended biomarkers in mCRC relative to standard of care (SOC) tissue testing. PATIENTS AND METHODS: Prospectively enrolled patients with previously untreated mCRC undergoing physician discretion SOC tissue genotyping submitted pretreatment blood samples for comprehensive circulating tumor DNA (ctDNA) analysis with Guardant360 and targeted RAS and BRAF analysis with OncoBEAM. RESULTS: Among 155 patients, physician discretion SOC tissue genotyping identified a guideline-recommended biomarker in 82 patients, versus 88 identified with comprehensive ctDNA (52.9% versus 56.8%, noninferiority demonstrated down to α = 0.005) and 69 identified with targeted PCR ctDNA analysis (52.9% versus 44.5%, noninferiority rejected at α = 0.05). Utilizing ctDNA in addition to tissue increased patient identification for a guideline-recommended biomarker by 19.5% by rescuing those without tissue results either due to tissue insufficiency, test failure, or false negatives. ctDNA median TAT was significantly faster than tissue testing when the complete process from sample acquisition to results was considered (median 10 versus 27 days, P < 0.0001), resulting in accelerated biomarker discovery, with 52.0% biomarker-positive patients identified by ctDNA versus 10.2% by SOC tissue 10 days after sample collection (P < 0.0001). CONCLUSIONS: Comprehensive ctDNA genotyping accurately identifies guideline-recommended biomarkers in patients with mCRC at a rate at least as high as SOC tissue genotyping, in a much shorter time. Based on these findings, the addition of ctDNA genotyping to clinical practice has significant potential to improve the care of patients with mCRC.

Priming with Small Molecule-Based Biostimulants to Improve Abiotic Stress Tolerance in Arabidopsis thaliana.

Biostimulants became a hotspot in the fight to alleviate the consequences of abiotic stresses in crops. Due to their complex nature, it is challenging to obtain stable and reproducible final products and more challenging to define their mechanism of action. As an alternative, small molecule-based biostimulants, such as polyamines have promoted plant growth and improved stress tolerance. However, profound research about their mechanisms of action is still missing. To go further, we tested the effect of putrescine (Put) and its precursor ornithine (Orn) and degradation product 1,3-diaminopropane (DAP) at two different concentrations (0.1 and 1 mM) as a seed priming on in vitro Arabidopsis seedlings grown under optimal growth conditions, osmotic or salt stress. None of the primings affected the growth of the seedlings in optimal conditions but altered the metabolism of the plants. Under stress conditions, almost all primed plants grew better and improved their greenness. Only Orn-primed plants showed different plant responses. Interestingly, the metabolic analysis revealed the implication of the N- acetylornithine and Orn and polyamine conjugation as the leading player regulating growth and development under control and stress conditions. We corroborated polyamines as very powerful small molecule-based biostimulants to alleviate the adverse abiotic stress effects.

Consensus in acute myeloid leukemia in Mexico.

Acute myeloid leukemia (AML) comprises a heterogeneous group of hematopoietic cell neoplasms of myeloid lineage that arise from the clonal expansion of their precursors in the bone marrow, interfering with cell differentiation, leading to a syndrome of bone marrow failure. AML is a consequence of genetic and epigenetic changes (point mutations, gene rearrangements, deletions, amplifications, and arrangements in epigenetic changes that influence gene expression) in hematopoietic precursor cells, which create a clone of abnormal cells that are capable of proliferating but cannot differentiate into mature hematopoietic cells or undergo programmed cell death. The diagnosis requires more than 20% myeloid blasts in the bone marrow and certain cytogenic abnormalities. Treatment will depend on age, comorbidities, and cytogenetic risk among the most frequent.

La leucemia mieloide aguda (LMA) comprende un grupo heterogéneo de neoplasias de células hematopoyéticas de linaje mieloide que surgen de la expansión clonal de sus precursores en la médula ósea, interfiriendo con la diferenciación celular, lo que conlleva a un síndrome de falla medular. La LMA es una consecuencia de cambios genéticos y epigenéticos (mutaciones puntuales, rearreglos de genes, deleciones, amplificaciones y arreglos en cambios epigenéticos que influyen en la expression del gen) en las células hematopoyéticas precursoras, la cual crea una clona de células anormales que son capaces de proliferar, pero no se pueden diferenciar en células hematopoyéticas maduras ni sufrir una muerte celular programada. El diagnostic requiere más del 20% de blastos mieloides en médula ósea y ciertas anormalidades citogénicas. El tratamiento dependerá de la edad, comorbilidades, riesgo citogenético entre las más frecuentes.

The still-face paradigm in Latin American mother-child dyads at 2 and 3 years: Effects of socioeconomic status and temperament.

The still-face paradigm (SFP) is a common method in infancy used to assess emotion regulation and interactions when an adult (typically the caregiver) abruptly stops a positive interaction with a child and switches to a more neutral affect. The effect of this paradigm has been studied in different countries and age ranges, but research in Latin America and with toddlers (e.g., 2-3 years old) of different socioeconomic backgrounds is scarce. The current study analyzed caregiver-child interactions in this novel sample, to analyze the possibility of generalization of the typical response of this paradigm (i.e., less positive affect, reduced gaze, and more negative affect in children when parent affect changes). The sample consisted of 114 caregiver-child dyads from low to middle socioeconomic status (SES) (children's Mage = 26.61 months, SD = 6.73, range = 18-36; 61 girls). The SFP modified version (i.e., on the floor and with a series of standardized toys), the temperament Early Childhood Behavior Questionnaire adapted for Argentina, and an SES scale were used. The typical SFP response was observed in Latin American children. In addition, older children and children with higher SES exhibited better general regulation, and there were weak associations with temperament. For gender differences, boys demonstrated more aggressive behaviors at Phase II. Results from this study suggest that children's response to this paradigm is an unconditional response to the lack of social reinforcers and is only partially associated with social and individual variables.

Bioreactor-Based De-epithelialization of Long-Segment Tracheal Grafts.

Tissue engineering techniques to generate a graft ex vivo is an exciting field of research. In particular, the use of biological scaffolds has shown to be promising in a clinical setting. In this approach, decellularized donor scaffolds are obtained following detergent-based enzymatic treatment to remove donor cells and subsequently repopulated with recipient specific cells. Herein, we describe our bioreactor-based partial decellularization approach to generate hybrid tracheal grafts. Using a short detergent-based treatment with sodium dodecyl sulfate (SDS), we remove the epithelium and maintain the structural integrity of the donor grafts by keeping the cartilage alive. The following will be a step-by-step description of the bioreactor system setup and partial decellularization protocol to obtain a de-epithelialized tracheal graft.

Consenso de leucemia mieloide aguda en México / Mexican consensus in acute myeloid leukemia in Mexico

resumen está disponible en el texto completo

Abstract Acute myeloid leukemia (AML) comprises a heterogeneous group of hematopoietic cell neoplasms of myeloid lineage that arise from the clonal expansion of their precursors in the bone marrow, interfering with cell differentiation, leading to a syndrome of bone marrow failure. AML is a consequence of genetic and epigenetic changes (point mutations, gene rearrangements, deletions, amplifications, and arrangements in epigenetic changes that influence gene expression) in hematopoietic precursor cells, which create a clone of abnormal cells that are capable of proliferating but cannot differentiate into mature hematopoietic cells or undergo programmed cell death. The diagnosis requires more than 20% myeloid blasts in the bone marrow and certain cytogenic abnormalities. Treatment will depend on age, comorbidities, and cytogenetic risk among the most frequent.

Intestinal obstruction secundary to gallstone ileus: case report.

Gallstone ileus is an intestinal obstruction that is secondary to the presence of gallstones in the small intestine. It is a rare complication of cholelithiasis, which represents 1-3% of the causes of intestinal obstruction. The diagnosis is difficult given that the symptoms are nonspecific with intermittent intestinal obstruction, Rigler's triad (pneumobilia, stone and abdominal distention) is pathognomonic. Among the diagnostic aids are abdominal radiography, ultrasound and abdominal tomography. Treatment should be individualized depending on the patient's conditions, with laparotomy with enterotomy being the treatment of choice.

El íleo biliar es una obstrucción intestinal secundaria a la presencia de cálculos biliares en el intestino delgado. Es una complicación rara de la colelitiasis y representa el 1-3% de las causas de obstrucción intestinal. El diagnóstico es difícil dado que la clínica es inespecífica, con un cuadro de oclusión intestinal intermitente; la tríada de Rigler (neumobilia, lito y distensión abdominal) es patognomónica. Dentro de los auxiliares diagnósticos se encuentran la radiografía de abdomen, el ultrasonido y la tomografía computarizada abdominal. El tratamiento debe individualizarse dependiendo de las condiciones del paciente, siendo de elección la laparotomía con enterotomía.

Short-Term Preclinical Application of Functional Human Induced Pluripotent Stem Cell-Derived Airway Epithelial Patches.

Airway pathologies including cancer, trauma, and stenosis lack effective treatments, meanwhile airway transplantation and available tissue engineering approaches fail due to epithelial dysfunction. Autologous progenitors do not meet the clinical need for regeneration due to their insufficient expansion and differentiation, for which human induced pluripotent stem cells (hiPSCs) are promising alternatives. Airway epithelial patches are engineered by differentiating hiPSC-derived airway progenitors into physiological proportions of ciliated (73.9 ± 5.5%) and goblet (2.1 ± 1.4%) cells on a silk fibroin-collagen vitrigel membrane (SF-CVM) composite biomaterial for transplantation in porcine tracheal defects ex vivo and in vivo. Evaluation of ex vivo tracheal repair using hiPSC-derived SF-CVM patches demonstrate native-like tracheal epithelial metabolism and maintenance of mucociliary epithelium to day 3. In vivo studies demonstrate SF-CVM integration and maintenance of airway patency, showing 80.8 ± 3.6% graft coverage with an hiPSC-derived pseudostratified epithelium and 70.7 ± 2.3% coverage with viable cells, 3 days postoperatively. The utility of bioengineered, hiPSC-derived epithelial patches for airway repair is demonstrated in a short-term preclinical survival model, providing a significant leap for airway reconstruction approaches.

Commercial Washing Detergents-Assisted Alkaline Pretreatment for Lignocellulosic Sugars Production: A First Report.

Lignocellulosic sugars are the major renewable building blocks for green fuels and chemicals production. However, the implication of an effective pretreatment process is an inevitable process to access the biomass sugars. Alkaline pretreatment is a viable pretreatment process, causing a selective removal of lignin, with a minimum degradation of carbohydrates, increasing porosity and surface area, eventually enhancing enzymatic hydrolysis. Here, we have assessed commercial cloth washing detergents as catalytic agents, for the lignin removal from sugarcane bagasse. Three different detergents (Brilhiante® (B), Omo® (O), Sabonito Flash® (F)) were tested using three different concentrations (5, 10 and 15%) with and without pH adjustment. Pretreatment with O5pH (5% Omo®, pH 12) showed the maximum lignin removal (81.14%) and retainment of cellulose (44.15%), and hemicellulose (29.71%) in the pretreated bagasse. The maximum sugars (26.62 g/L) were released from the O10pH-pretreated sugarcane bagasse. This study shows the potential of washing detergents as the new potential catalytic agents for the pretreatment of biomass for efficient sugars recovery and retaining maximum lignin in the pretreated substrate.

Phloem exudate metabolic content reflects the response to water-deficit stress in pea plants (Pisum sativum L.).

Drought stress impacts the quality and yield of Pisum sativum. Here, we show how short periods of limited water availability during the vegetative stage of pea alters phloem sap content and how these changes are connected to strategies used by plants to cope with water deficit. We have investigated the metabolic content of phloem sap exudates and explored how this reflects P. sativum physiological and developmental responses to drought. Our data show that drought is accompanied by phloem-mediated redirection of the components that are necessary for cellular respiration and the proper maintenance of carbon/nitrogen balance during stress. The metabolic content of phloem sap reveals a shift from anabolic to catabolic processes as well as the developmental plasticity of P. sativum plants subjected to drought. Our study underlines the importance of phloem-mediated transport for plant adaptation to unfavourable environmental conditions. We also show that phloem exudate analysis can be used as a useful proxy to study stress responses in plants. We propose that the decrease in oleic acid content within phloem sap could be considered as a potential marker of early signalling events mediating drought response.

Computational fluid dynamics for enhanced tracheal bioreactor design and long-segment graft recellularization.

Successful re-epithelialization of de-epithelialized tracheal scaffolds remains a challenge for tracheal graft success. Currently, the lack of understanding of the bioreactor hydrodynamic environment, and its relation to cell seeding outcomes, serve as major obstacles to obtaining viable tracheal grafts. In this work, we used computational fluid dynamics to (a) re-design the fluid delivery system of a trachea bioreactor to promote a spatially uniform hydrodynamic environment, and (b) improve the perfusion cell seeding protocol to promote homogeneous cell deposition. Lagrangian particle-tracking simulations showed that low rates of rotation provide more uniform circumferential and longitudinal patterns of cell deposition, while higher rates of rotation only improve circumferential uniformity but bias cell deposition proximally. Validation experiments with human bronchial epithelial cells confirm that the model accurately predicts cell deposition in low shear stress environments. We used the acquired knowledge from our particle tracking model, as a guide for long-term tracheal repopulation studies. Cell repopulation using conditions resulting in low wall shear stress enabled enhanced re-epithelialization of long segment tracheal grafts. While our work focuses on tracheal regeneration, lessons learned in this study, can be applied to culturing of any tissue engineered tubular scaffold.

Palbociclib in combination with endocrine therapy versus capecitabine in hormonal receptor-positive, human epidermal growth factor 2-negative, aromatase inhibitor-resistant metastatic breast cancer: a phase III randomised controlled trial-PEARL.

BACKGROUND: Palbociclib plus endocrine therapy (ET) is the standard treatment of hormone receptor-positive and human epidermal growth factor receptor 2-negative, metastatic breast cancer (MBC). However, its efficacy has not been compared with that of chemotherapy in a phase III trial. PATIENTS AND METHODS: PEARL is a multicentre, phase III randomised study in which patients with aromatase inhibitor (AI)-resistant MBC were included in two consecutive cohorts. In cohort 1, patients were randomised 1 : 1 to palbociclib plus exemestane or capecitabine. On discovering new evidence about estrogen receptor-1 (ESR1) mutations inducing resistance to AIs, the trial was amended to include cohort 2, in which patients were randomised 1 : 1 between palbociclib plus fulvestrant and capecitabine. The stratification criteria were disease site, prior sensitivity to ET, prior chemotherapy for MBC, and country of origin. Co-primary endpoints were progression-free survival (PFS) in cohort 2 and in wild-type ESR1 patients (cohort 1 + cohort 2). ESR1 hotspot mutations were analysed in baseline circulating tumour DNA. RESULTS: From March 2014 to July 2018, 296 and 305 patients were included in cohort 1 and cohort 2, respectively. Palbociclib plus ET was not superior to capecitabine in both cohort 2 [median PFS: 7.5 versus 10.0 months; adjusted hazard ratio (aHR): 1.13; 95% confidence interval (CI): 0.85-1.50] and wild-type ESR1 patients (median PFS: 8.0 versus 10.6 months; aHR: 1.11; 95% CI: 0.87-1.41). The most frequent grade 3-4 toxicities with palbociclib plus exemestane, palbociclib plus fulvestrant and capecitabine, respectively, were neutropenia (57.4%, 55.7% and 5.5%), hand/foot syndrome (0%, 0% and 23.5%), and diarrhoea (1.3%, 1.3% and 7.6%). Palbociclib plus ET offered better quality of life (aHR for time to deterioration of global health status: 0.67; 95% CI: 0.53-0.85). CONCLUSIONS: There was no statistical superiority of palbociclib plus ET over capecitabine with respect to PFS in MBC patients resistant to AIs. Palbociclib plus ET showed a better safety profile and improved quality of life.