Hypertonic saline and heart failure: "sodium-centric" or "chlorine-centric"?

Up to 50% of patients admitted for heart failure (HF) have congestion at discharge despite diagnostic and therapeutic advances. Both persistent congestion and diuretic resistance are associated with worse prognosis. The combination of hypertonic saline and loop diuretic has shown promising results in different studies. However, it has not yet achieved a standardized use, partly because of the great heterogeneity in the concentration of sodium chloride, the dose of diuretic or the amount of sodium in the diet. Classically, the movement of water from the intracellular space due to an increase in extracellular osmolarity has been postulated as the main mechanism involved. However, chloride deficit is postulated as the main up-regulator of plasma volume changes, and its correction may be the main mechanism involved. This "chloride centric" approach to heart failure opens the door to therapeutic strategies that would include diuretics to correct hypochloremia, as well as sodium free chloride supplementation.

Regional Workshop on Optimization of Protection in Pediatric Interventional Radiology in Latin American and Caribbean Countries.

ABSTRACT: The purpose of this article is to describe the activities developed within the framework "Regional Workshop on Optimization of Protection in Pediatric Interventional Radiology in Latin American and Caribbean countries," developed between October 16th and 19th of the year 2023 in the city of San José, Costa Rica. The workshop was carried out as part of a joint work between the Pan American Health Organization (PAHO) and the World Health Organization (WHO), in cooperation with the International Atomic Energy Agency (IAEA). The main objective of the regional workshop was to gather the experiences and future work planning among participants in the Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean (OPRIPALC) program. It involved professionals from 14 centers across 11 countries in the region, along with 4 experts from PAHO/WHO/IAEA. The work modalities during the workshop consisted of keynote presentations, individual presentations, group work, and general discussions. An online survey was carried out after the workshop, with the objective of knowing the opinion of the event participants and determining the impact and projection of the OPRIPALC program. During the workshop the centers had to present their experiences: the use of the DOLQA dose management system was presented and work was done on the consensus document on good practices. The activities, topics and organization of the workshop were valued positively by the participants. There is unanimity among the centers that the OPRIPALC program has had a positive impact and they wish to continue actively participating in the next biennium.

Uncovering phytochemicals quantitative evolution in avocado fruit mesocarp during ripening: A targeted LC-MS metabolic exploration of Hass, Fuerte and Bacon varieties.

Avocado ripening entails intricate physicochemical transformations resulting in desirable characteristics for consumption; however, its impact on specific metabolites and its cultivar dependence remains largely unexplored. This study employed LC-MS to quantitatively monitor 30 avocado pulp metabolites, including phenolic compounds, amino acids, nucleosides, vitamins, phytohormones, and related compounds, from unripe to overripe stages, in three commercial varieties (Hass, Fuerte, and Bacon). Multivariate statistical analysis revealed significant metabolic variations between cultivars, leading to the identification of potential varietal markers. Most monitored metabolites exhibited dynamic quantitative changes. Although phenolic compounds generally increased during ripening, exceptions such as epicatechin and chlorogenic acid were noted. Amino acids and derivatives displayed a highly cultivar-dependent evolution, with Fuerte demonstrating the highest concentrations and most pronounced fluctuations. In contrast to penstemide, uridine and abscisic acid levels consistently increased during ripening. Several compounds characteristic of the Bacon variety were delineated but require further research for identification and role elucidation.

Evidence on the benefits of probiotics for preterm infants.

This article reviews the evidence for the use of different strains of probiotics in the prevention of prevalent pathologies in premature neonates. A systematic review was conducted of the use of probiotics in neonates with less than 37 weeks of gestational age, based on a search for systematic reviews and observational and experimental studies performed during the period from January 2014 to February 2021. For this purpose, the PubMed, MEDLINE and Cochrane Library databases were consulted. The aim of this article was to review the existing data on the relationship between the administration of probiotics (with different strains and doses) and the risk of necrotising enterocolitis, mortality, late sepsis and other disease parameters in premature infants. The literature search obtained 240 articles, of which we selected 16, representing a total sample of over 200,000 premature infants. Analysis of the data obtained reveals statistical evidence that the combined administration of probiotics (especially of Lactobacillus and Bifidobacterium strains) reduces the incidence of grade II or higher necrotising enterocolitis, all-cause mortality, late sepsis, length of hospital stay and time until complete enteral nutrition is achieved. However, no benefits were apparent with respect to alleviating bronchopulmonary dysplasia, retinopathy of prematurity or intraventricular haemorrhage. Further research is needed to determine the most appropriate strains, doses and treatment duration for preterm infants to achieve the health benefits identified.

Lipid signature associated with chronic colon inflammation reveals a dysregulation in colonocyte differentiation process.

Inflammatory Bowel Disease (IBD) comprises a heterogeneous group of chronic inflammatory conditions of the gastrointestinal tract that include ulcerative colitis (UC) and Crohn's disease. Although the etiology is not well understood, IBD is characterized by a loss of the normal epithelium homeostasis that disrupts the intestinal barrier of these patients. Previous work by our group demonstrated that epithelial homeostasis along the colonic crypts involves a tight regulation of lipid profiles. To evaluate whether lipidomic profiles conveyed the functional alterations observed in the colonic epithelium of IBD, we performed matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) analyses of endoscopic biopsies from inflamed and non-inflamed segments obtained from UC patients. Our results indicated that lipid profiling of epithelial cells discriminated between healthy and UC patients. We also demonstrated that epithelial cells of the inflamed mucosa were characterized by a decrease in mono- and di-unsaturated fatty acid-containing phospholipids and higher levels of arachidonic acid-containing species, suggesting an alteration of the lipid gradients occurring concomitantly to the epithelial differentiation. This result was reinforced by the immunofluorescence analysis of EPHB2 and HPGD, markers of epithelial cell differentiation, sustaining that altered lipid profiles were at least partially due to a faulty differentiation process. Overall, our results showed that lipid profiling by MALDI-MSI faithfully conveys molecular and functional alterations associated with the inflamed epithelium, providing the foundation for a novel molecular characterization of UC patients.

Differences in Volatile Organic Compounds Between Concussed and Non-concussed Division I Athletes.

Introduction Diagnosing a concussion is challenging because of complex and variable symptoms. Establishing a viable biomarker of injury may rely on physiologic measurements rather than symptomology. Volatile organic compounds (VOCs) such as breath acetone have been identified as potential physiological markers that can capture changes in the utilization of energy substrates post-concussion. Here, we aimed to explore whether differences in VOCs exist between concussed and non-concussed athletes at the initial and later stages of injury recovery. Methods Six (N=6) non-concussed athletes were enrolled as control participants prior to the competitive season. Control participants' breath acetone, heart rate, and anthropometric measures were obtained at rest and throughout a single exercise challenge by breathalyzer. Six (N=6) athletes diagnosed with concussion during the competitive season had breath acetone measured daily until cleared to return to activity or approximately four weeks following enrollment where they participated in an exit exercise challenge having breath acetone, heart rate, and anthropometric measures obtained. Comparisons were made between at-rest measures of concussed and non-concussed participants at multiple time points during the recovery period. Paired t-test comparisons with individuals serving as their own control were used to determine individual differences in recovery. Visual graphs were used to demonstrate differences in obtained measures amongst individuals and between groups during the exercise challenges. Results Results demonstrated statistically significant differences in breath acetone between concussed and control participants when the highest day measured during the first week of concussion was compared to the control participant's resting values (P=0.017). Additionally, when the concussed participants served as their own control and their highest measured day of the first week post-concussion was compared to values when cleared to return to activity or at 26 days post-concussion, there was a significant difference in breath acetone (P=0.028). Comparing breath acetone during exercise between non-concussed and cleared concussed participants or four weeks post-injury, demonstrated no significant differences throughout the challenge or at rest prior. Visual graph comparisons in a single participant before and after concussion suggest differences may appear following exercise during the recovery period. Discussion These results suggest VOCs, particularly breath acetone, have the potential to serve as diagnostic markers of concussion. However, longitudinal research within larger cohorts and with equipment able to expel VOCs other than acetone from measures are needed to make informed recommendations.

EXPRESS: Landmark Publications in Analytical Atomic Spectrometry: Fundamentals and Instrumentation Development.

The almost-two-centuries history of spectrochemical analysis has generated a body of literature so vast that it has become nearly intractable for experts, much less for those wishing to enter the field. Authoritative, focused reviews help to address this problem but become so granular that the overall directions of the field are lost. This broader perspective can be provided partially by general overviews but then the thinking, experimental details, theoretical underpinnings and instrumental innovations of the original work must be sacrificed. In the present compilation, this dilemma is overcome by assembling the most impactful publications in the area of analytical atomic spectrometry. Each entry was proposed by at least one current expert in the field and supported by a narrative that justifies its inclusion. The entries were then assembled into a coherent sequence and returned to contributors for a round-robin review.

sp2-Iminosugar azobenzene O-glycosides: Light-sensitive glycosidase inhibitors with unprecedented tunability and switching factors.

The conventional approach to developing light-sensitive glycosidase activity regulators, involving the combination of a glycomimetic moiety and a photoactive azobenzene module, results in conjugates with differences in glycosidase inhibitory activity between the interchangeable E and Z-isomers at the azo group that are generally below one-order of magnitude. In this study, we have exploited the chemical mimic character of sp2-iminosugars to access photoswitchable p- and o-azobenzene α-O-glycosides based on the gluco-configured representative ONJ. Notably, we achieved remarkably high switching factors for glycosidase inhibition, favoring either the E- or Z-isomer depending on the aglycone structure. Our data also indicate a correlation between the isomeric state of the azobenzene module and the selectivity towards α- and ß-glucosidase isoenzymes. The most effective derivative reached over a 103-fold higher inhibitory potency towards human ß-glucocerebrosidase in the Z as compared with the E isomeric form. This sharp contrast is compatible with ex-vivo activation and programmed self-deactivation at physiological temperatures, positioning it as a prime candidate for pharmacological chaperone therapy in Gaucher disease. Additionally, our results illustrate that chemical tailoring enables the engineering of photocommutators with the ability to toggle inhibition between α- and ß-glucosidase enzymes in a reversible manner, thus expanding the versatility and potential therapeutic applications of this approach.

Regional Differences in Diagnosis Journey and Healthcare Utilization: Results from the International Map of Axial Spondyloarthritis (IMAS).

INTRODUCTION: To assess differences in the diagnosis journey and access to care in a large sample of patients with axial spondyloarthritis (axSpA) from around the world, included in the International Map of Axial Spondyloarthritis (IMAS). METHODS: IMAS was a cross-sectional online survey (2017-2022) of 5557 unselected patients with axSpA from 27 countries. Across five worldwide geographic regions, the patient journey until diagnosis and healthcare utilization in the last 12 months prior to survey were evaluated. Univariable and multivariable linear regression was used to analyze factors associated with higher healthcare utilization. RESULTS: Of 5557 participants in IMAS, the diagnosis took an average of 7.4 years, requiring more than two visits to HCPs (77.7% general practitioner and 51.3% rheumatologist), and more than two diagnostic tests [67.5% performed human leukocyte antigen B27 (HLA-B27), 64.2% x-ray, and 59.1% magnetic resonance imaging (MRI) scans]. North America and Europe were the regions with the highest number of healthcare professional (HCP) visits for diagnosis, while the lowest number of visits was in the Asian region. In the previous 12 months, 94.9% (n = 5272) used at least one healthcare resource, with an average of 29 uses per year. The regions with the highest healthcare utilization were Latin America, Europe, and North America. In the multiple linear regression, factors associated with higher number of healthcare utilization were younger age (b =  - 0.311), female gender (b = 7.736), higher disease activity (b = 1.461), poorer mental health (b = 0.624), greater functional limitation (b = 0.300), greater spinal stiffness (b = 1.527), and longer diagnostic delay (b = 0.104). CONCLUSION: The diagnosis of axSpA usually takes more than two visits to HCPs and at least 7 years. After diagnosis, axSpA is associated with frequent healthcare resource use. Younger age, female gender, higher disease activity, poorer mental health, greater functional limitation, greater spinal stiffness, and longer diagnostic delay are associated with higher healthcare utilization. Europe and North America use more HCP visits and diagnostic tests before and after diagnosis than the other regions.

International Map of Axial Spondyloarthritis (IMAS): results from the perspective of 5557 patients from 27 countries around the globe.

BACKGROUND: The International Map of Axial Spondyloarthritis (IMAS) is a global initiative aimed to assess the impact and burden of axial spondyloarthritis (axSpA) and identify the unmet needs from the patient's perspective. METHOD: IMAS is a collaboration between the Axial Spondyloarthritis International Federation (ASIF), the University of Seville, Novartis Pharma AG and steered by a scientific committee. IMAS collected information through an online cross-sectional survey (2017-2022) from unselected patients with axSpA from Europe, Asia, North America, Latin America and Africa who completed a comprehensive questionnaire containing over 120 items. RESULTS: 5557 patients with axSpA participated in IMAS. Mean age was 43.9 ±12.8 years, 55.4% were female, 46.2% had a university education and 51.0% were employed. The mean diagnostic delay was 7.4 ±9.0 years (median: 4.0), and the mean symptom duration was 17.1 ±13.3 years. 75.0% of patients had active disease (Bath Ankylosing Spondylitis Disease Activity Index ≥4), and 59.4% reported poor mental health (12-item General Health Questionnaire ≥3). In the year before the survey, patients had visited primary care physicians 4.6 times and the rheumatologist 3.6 times. 78.6% had taken non-steroidal anti-inflammatory drug ever, 48.8% biological disease-modifying antirheumatic drugs and 43.6% conventional synthetic disease-modifying antirheumatic drugs. Patients's greatest fear was disease progression (55.9%), while the greatest hope was to be able to relieve pain (54.2%). CONCLUSIONS: IMAS shows the global profile of patients with axSpA, highlighting unmet needs, lengthy delays in diagnosis and high burden of disease in patients with axSpA worldwide. This global information will enable more detailed investigations to obtain evidence on the critical issues that matter to patients around the world to improve their care and quality of life.

Crystal Nucleation in Supercooled Atomic Liquids.

The liquid-to-solid phase transition is a complex process that is difficult to investigate experimentally with sufficient spatial and temporal resolution. A key aspect of the transition is the formation of a critical seed of the crystalline phase in a supercooled liquid, that is, a liquid in a metastable state below the melting temperature. This stochastic process is commonly described within the framework of classical nucleation theory, but accurate tests of the theory in atomic and molecular liquids are challenging. Here, we employ femtosecond x-ray diffraction from microscopic liquid jets to study crystal nucleation in supercooled liquids of the rare gases argon and krypton. Our results provide stringent limits to the validity of classical nucleation theory in atomic liquids, and offer the long-sought possibility of testing nonclassical extensions of the theory.

Chloroplast envelope K+/H+ antiporters are involved in cytosol pH regulation.

Variations in light intensity induce cytosol pH changes in photosynthetic tissues, providing a possible signal to adjust a variety of biochemical, physiological and developmental processes to the energy status of the cells. It was shown that these pH changes are partially due to the transport of protons in or out of the thylakoid lumen. However, the ion transporters in the chloroplast that transmit these pH changes to the cytosol are not known. KEA1 and KEA2 are K+/H+ antiporters in the chloroplast inner envelope that adjust stromal pH in light-to-dark transitions. We previously determined that stromal pH is higher in kea1kea2 mutant cells. In this study, we now show that KEA1 and KEA2 are required to attenuate cytosol pH variations upon sudden light intensity changes in leaf mesophyll cells, showing they are important components of the light-modulated pH signalling module. The kea1kea2 mutant mesophyll cells also have a considerably less negative membrane potential. Membrane potential is dependent on the activity of the plasma membrane proton ATPase and is regulated by secondary ion transporters, mainly potassium channels in the plasma membrane. We did not find significant differences in the activity of the plasma membrane proton pump but found a strongly increased membrane permeability to protons, especially potassium, of the double mutant plasma membranes. Our results indicate that chloroplast envelope K+/H+ antiporters not only affect chloroplast pH but also have a strong impact on cellular ion homeostasis and energization of the plasma membrane.

Disruption of the mitochondrial network in a mouse model of Huntington's disease visualized by in-tissue multiscale 3D electron microscopy.

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded CAG repeat in the coding sequence of huntingtin protein. Initially, it predominantly affects medium-sized spiny neurons (MSSNs) of the corpus striatum. No effective treatment is still available, thus urging the identification of potential therapeutic targets. While evidence of mitochondrial structural alterations in HD exists, previous studies mainly employed 2D approaches and were performed outside the strictly native brain context. In this study, we adopted a novel multiscale approach to conduct a comprehensive 3D in situ structural analysis of mitochondrial disturbances in a mouse model of HD. We investigated MSSNs within brain tissue under optimal structural conditions utilizing state-of-the-art 3D imaging technologies, specifically FIB/SEM for the complete imaging of neuronal somas and Electron Tomography for detailed morphological examination, and image processing-based quantitative analysis. Our findings suggest a disruption of the mitochondrial network towards fragmentation in HD. The network of interlaced, slim and long mitochondria observed in healthy conditions transforms into isolated, swollen and short entities, with internal cristae disorganization, cavities and abnormally large matrix granules.

Factors Associated with Poor Mental Health in Patients with Axial Spondyloarthritis: Results from the International Map of Axial Spondyloarthritis (IMAS).

BACKGROUND: This study aims to assess the prevalence of poor mental health in axial spondyloarthritis (axSpA) and its associated factors in a large sample of patients from the International Map of Axial Spondyloarthritis (IMAS) study from around the globe. METHODS: IMAS is a cross-sectional online survey (2017-2022) that includes 5557 unselected patients with axSpA worldwide. Mental health was evaluated by the 12-item General Health Questionnaire (GHQ-12) and the cut-off point for poor mental health was set at 3. Logistic regression analysis was used to evaluate relationships between the investigated factors and poor mental health (GHQ-12≥3) in patients with axSpA (n=4335). RESULTS: Of 5351 patients, the mean of GHQ-12 was 4.7 and 59.4% were having poor mental health, being 69.9% in South Africa, 63.7% in Latin America, 60.8% in Europe, 54.3% in North America and 51.8% in Asia. Overall, 40.5% and 37.2% of patients experienced anxiety and depression. The factors associated with poor mental health were younger age (OR=0.99), female gender (OR=1.16), being on sick leave or unemployed (OR=1.63), non-physical activity (OR=1.22), smoking (OR=1.20), higher Bath Ankylosing Spondylitis Disease Activity Index [BASDAI] (OR=1.42), functional limitation (OR=1.02) and shorter symptoms duration (OR=0.98). CONCLUSIONS: Globally, 6 in 10 patients with axSpA had poor mental health, with a higher proportion in South Africa and lower in Asia. The factors associated with poor mental health include domains such as younger age, female gender, employment difficulties, harmful habits, disease burden and symptom duration. A holistic management approach to axSpA should encompass both physical and mental health.

New Protocol for Twinning of Raman Devices Toward a Raman Intensity Harmonization.

The use of Raman spectroscopy has rapidly been on the rise across a great number of industries where comparability, reproducibility, and reliability of the data are of paramount importance. However, controlling the intensity of the Raman signal depends on a large number of factors such as the wavelength of the laser light, the optical components of each device, or the number of molecules in the illuminated volume. For this reason, in this study, a new protocol has been applied to twin Raman devices to achieve a conversion of the signal between them, by pairing the intensity response of the units using a reference sample. The new reference material is a homogenous dispersion of a 0.5 wt% anatase (titanium dioxide, or TiO2) in an epoxy resin matrix, with deviations <2.5% in Raman intensity across the reference material. The proposed protocol for Raman-twinned devices takes a well-defined approach that leads to obtaining a correction factor that relates the differences in the signal intensity between the two Raman devices, in order to obtain the same Raman intensity counts. The performance of the proposed method was evaluated based on the data from the devices, which presented the most common user cases: twinning Raman devices of the non-confocal same model for two different wavelengths; and twinning confocal and non-confocal devices. The results obtained show that the protocol has worked for both of the Raman twinning cases, allowing the Raman intensity harmonization of Raman spectra between two different devices.

The effect of sociodemographic characteristics, academic factors, and individual health behaviors on psychological well-being among college students.

Objective: This study aimed to measure the potential relationships between sociodemographic characteristics, academic factors, body mass index (BMI), financial challenges, individual health behaviors, impact of COVID-19, and psychological well-being (PWB) among students. Participants: Undergraduate college students. Methods: Data from the National College Health Assessment III (American College Health Association [ACHA]) were used (n = 1,439). Differences in absolute values among PWB groups were analyzed using analysis of variance (ANOVA). To measure the influence of all factors combined on PWB, multiple regression analyses were performed. Results: Significant differences were observed in age, GPA, financial challenges, and individual health behaviors by PWB groups (p < .05). Being older, being female, having a higher GPA, being a full-time student, having a higher intake of vegetables, taking less time to fall asleep, and having lower stress levels were significantly positively associated with higher PWB scores (p < .05). Conclusions: Multiple considerations related to the academic environment and individual behaviors seem to influence PWB among college students.

Markerauto2: A fast and robust fully automatic fiducial marker-based tilt series alignment software for electron tomography.

Cryoelectron tomography (cryo-ET) has become an indispensable technology for visualizing in situ biological ultrastructures, where the tilt series alignment is the key step to obtain a high-resolution three-dimensional reconstruction. Specifically, with the advent of high-throughput cryo-ET data collection, there is an increasing demand for high-accuracy and fully automatic tilt series alignment, to enable efficient data processing. Here, we propose Markerauto2, a fast and robust fully automatic software that enables accurate fiducial marker-based tilt series alignment. Markerauto2 implements the following novel pipelines: (1) an accelerated high-precision fiducial marker detection with wavelet multiscale template, (2) an ultra-fast and robust fiducial marker tracking supported by hashed geometric features, (3) a high-angle fiducial marker supplementation strategy to produce more complete tracks, and (4) a precise and robust calibration of projection parameters with group-weighted parameter optimization. Comprehensive experiments conducted on both simulated and real-world datasets demonstrate the robustness, efficiency, and effectiveness of the proposed software.

Synergistic impact of innate immunity hyper-activation and endothelial dysfunction on the magnitude of organ failure in the infection-sepsis continuum.

OBJECTIVES: Identifying host response biomarkers implicated in the emergence of organ failure during infection is key to improving the early detection of this complication. METHODS: Twenty biomarkers of innate immunity, T-cell response, endothelial dysfunction, coagulation, and immunosuppression were profiled in 180 surgical patients with infections of diverse severity (IDS) and 53 with no infection (nIDS). Those better differentiating IDS/nIDS in the area under the curve were combined to test their association with the sequential organ failure assessment score by linear regression analysis in IDS. Results were validated in another IDS cohort of 174 patients. RESULTS: C-reactive protein, procalcitonin, pentraxin-3, lipocalin-2 (LCN2), tumoral necrosis factor-α, angiopoietin-2, triggering receptor expressed on myeloid cells-1 (TREM-1) and interleukin (IL)-15 yielded an area under the curve ≥0.75 to differentiate IDS from nIDS. The combination of LCN2, IL-15, TREM-1, angiopoietin-2 (Dys-4) showed the strongest association with sequential organ failure assessment score in IDS (adjusted regression coefficient; standard error; P): Dys-4 (3.55;0.44; <0.001), LCN2 (2.24; 0.28; <0.001), angiopoietin-2 (1.92; 0.33; <0.001), IL-15 (1.78; 0.40; <0.001), TREM-1(1.74; 0.46; <0.001), tumoral necrosis factor-α (1.60; 0.31; <0.001), pentraxin-3 (1.12; 0.18; <0.001), procalcitonin (0.85; 0.12; <0.001). Dys-4 provided similar results in the validation cohort. CONCLUSIONS: There is a synergistic impact of innate immunity hyper-activation (LCN2, IL-15, TREM-1) and endothelial dysfunction (angiopoietin-2) on the magnitude of organ failure during infection.

Quality and safety actions in primary care practices in COVID-19 pandemic: the PRICOV-19 study in Spain.

BACKGROUND: Primary Health Care (PHC) has been key element in detection, monitoring and treatment of COVID-19 cases in Spain. We describe how PHC practices (PCPs) organized healthcare to guarantee quality and safety and, if there were differences among the 17 Spanish regions according to the COVID-19 prevalence. METHODS: Cross-sectional study through the PRICOV-19 European Online Survey in PCPs in Spain. The questionnaire included structure and process items per PCP. Data collection was due from January to May 2021. A descriptive and comparative analysis and a logistic regression model were performed to identify differences among regions by COVID-19 prevalence (low < 5% or high ≥5%). RESULTS: Two hundred sixty-six PCPs answered. 83.8% of PCPs were in high prevalence regions. Over 70% PCPs were multi-professional teams. PCPs attended mainly elderly (60.9%) and chronic patients (53.0%). Regarding structure indicators, no differences by prevalence detected. In 77.1% of PCPs administrative staff were more involved in providing recommendations. Only 53% of PCPs had a phone protocol although 73% of administrative staff participated in phone triage. High prevalence regions offered remote assessment (20.4% vs 2.3%, p 0.004) and online platforms to download administrative documents more frequently than low prevalence (30% vs 4.7%, p < 0.001). More backup staff members were hired by health authorities in high prevalence regions, especially nurses (63.9% vs 37.8%, p < 0.001. OR:4.20 (1.01-8.71)). 63.5% of PCPs provided proactive care for chronic patients. 41.0% of PCPs recognized that patients with serious conditions did not know to get an appointment. Urgent conditions suffered delayed care in 79.1% of PCPs in low prevalence compared to 65.9% in high prevalence regions (p 0.240). A 68% of PCPs agreed on having inadequate support from the government to provide proper functioning. 61% of high prevalence PCPs and 69.5% of low ones (p: 0.036) perceived as positive the role of governmental guidelines for management of COVID-19. CONCLUSIONS: Spanish PCPs shared a basic standardized PCPs' structure and common clinical procedures due to the centralization of public health authority in the pandemic. Therefore, no relevant differences in safety and quality of care between regions with high and low prevalence were detected. Nurses and administrative staff were hired efficiently in response to the pandemic. Delay in care happened in patients with serious conditions and little follow-up for mental health and intimate partner violence affected patients was identified. Nevertheless, proactive care was offered for chronic patients in most of the PCPs.