An Opportunity for Management of Fatigue, Physical Condition, and Quality of Life Through Asynchronous Telerehabilitation in Patients After Acute Coronavirus Disease 2019: A Randomized Controlled Pilot Study.

OBJECTIVE: To compare the preliminary efficacy of asynchronous telerehabilitation in patients after acute coronavirus disease 2019 (COVID-19) on fatigue, physical condition, quality of life, and feasibility of this pilot study with that of a booklet format. DESIGN: Randomized pilot study with 2 intervention arms: asynchronous telerehabilitation group and booklet-based rehabilitation group, with 2 follow-ups at 3 and 6 months. SETTING: Hospital. PARTICIPANTS: Patients discharged after COVID-19 were recruited and evaluated (N=35). INTERVENTIONS: The intervention consisted of a 12-week multimodal rehabilitation program via telerehabilitation or by a booklet. MAIN OUTCOME MEASURES: Fatigue as the main outcome and functional status, quality of life, and feasibility as secondary outcomes were evaluated. RESULTS: After the intervention, there was no significant difference between groups in fatigue, but there were significant differences in favor of the asynchronous telerehabilitation group for the 6-Minute Walk Test (p=.008), the 30-Second Sit-to-Stand Test (p=.019), and physical quality of life (p=.035). These improvements were maintained throughout the 6-month follow-up. Telerehabilitation was shown to be a viable option, without incidents and with a higher adhesion (p=.028) than the booklet format. CONCLUSIONS: A multimodal rehabilitation program by means of asynchronous telerehabilitation appears as a more effective option than traditional formats in improving post-acute COVID-19 sequelae.

Abdominal normothermic regional perfusion in controlled donation after circulatory determination of death liver transplantation: Outcomes and risk factors for graft loss.

Postmortem normothermic regional perfusion (NRP) is a rising preservation strategy in controlled donation after circulatory determination of death (cDCD). Herein, we present results for cDCD liver transplants performed in Spain 2012-2019, with outcomes evaluated through December 31, 2020. Results were analyzed retrospectively and according to recovery technique (abdominal NRP [A-NRP] or standard rapid recovery [SRR]). During the study period, 545 cDCD liver transplants were performed with A-NRP and 258 with SRR. Median donor age was 59 years (interquartile range 49-67 years). Adjusted risk estimates were improved with A-NRP for overall biliary complications (OR 0.300, 95% CI 0.197-0.459, p < .001), ischemic type biliary lesions (OR 0.112, 95% CI 0.042-0.299, p < .001), graft loss (HR 0.371, 95% CI 0.267-0.516, p < .001), and patient death (HR 0.540, 95% CI 0.373-0.781, p = .001). Cold ischemia time (HR 1.004, 95% CI 1.001-1.007, p = .021) and re-transplantation indication (HR 9.552, 95% CI 3.519-25.930, p < .001) were significant independent predictors for graft loss among cDCD livers with A-NRP. While use of A-NRP helps overcome traditional limitations in cDCD liver transplantation, opportunity for improvement remains for cases with prolonged cold ischemia and/or technically complex recipients, indicating a potential role for complimentary ex situ perfusion preservation techniques.

Assessing Spaniard men's willingness and determinants to use a male contraceptive pill.

OBJECTIVE: As the clinical trials to develop male contraceptive pills are underway, understanding men's attitudes towards this contraceptive method is transcendental. This research was conducted to identify the degree of willingness and the determinants to use male contraceptive pill among Spaniard men. METHODS: A sample of 402 Spaniards men was presented with 36 scenarios comprising four within-subject factors (cost of pills, pill efficacy, side effects and context). In each scenario, a man is asked by his partner to use the contraceptive pill. Participants indicated their own willingness to use the pill in each circumstance. RESULTS: Cluster analysis revealed that participants took one of seven different positions regarding their willingness to use a contraceptive pill: never agree (10%); mainly depends on pill efficacy (6%); mainly depends on side effects (10%); depends on side effects and efficacy (12%); depends on context and side effects (12%); quite always (25%); always agree (25%). Participants' willingness to use contraceptive pills was more pronounced in the case of mild side effects and higher pill efficacy. CONCLUSION: Fifty percent of participants would use the male pill regardless of the circumstances. Access to this contraceptive method, when available, can contribute to greater equity in reproductive rights of the population.

Quality of Life in Hidradenitis Suppurativa: validation of the HSQoL-24.

To date, there are no disease-specific instruments in Spanish to assess quality of life of patients with hidradenitis suppurativa. A multicentre study was previously carried out in Spain between 2016 and 2017 to develop the Hidradenitis Suppurativa Quality of Life-24 (HSQoL-24), a disease-specific questionnaire to assess quality of life in patients with hidradenitis suppurativa. The objectiv-es of this study are to revalidate the HSQoL-24 in Spanish with a larger sample of patients, and to present the English version. In this multi-centre study in Spain, patients with hidradenitis suppurativa completed the HSQoL-24, the Dermatology Life Quality Index and the Skindex-29. The Hurley staging system was used to assess the severity of the disease. Validation of the questionnaire was carried out in 130 patients, of whom 75 (57.7%) were women. This study demonstrates adequate values of reliability and validity of the HSQoL-24, confirming the previous test re-test validation and making this questionnaire one of wide clinical validity in terms of results perceiv-ed by patients.

Normothermic regional perfusion vs. super-rapid recovery in controlled donation after circulatory death liver transplantation.

BACKGROUND & AIMS: Although there is increasing interest in its use, definitive evidence demonstrating a benefit for postmortem normothermic regional perfusion (NRP) in controlled donation after circulatory death (cDCD) liver transplantation is lacking. The aim of this study was to compare results of cDCD liver transplants performed with postmortem NRP vs. super-rapid recovery (SRR), the current standard for cDCD. METHODS: This was an observational cohort study including all cDCD liver transplants performed in Spain between June 2012 and December 2016, with follow-up ending in December 2017. Each donor hospital determined whether organ recovery was performed using NRP or SRR. The propensity scores technique based on the inverse probability of treatment weighting (IPTW) was used to balance covariates across study groups; logistic and Cox regression models were used for binary and time-to-event outcomes. RESULTS: During the study period, there were 95 cDCD liver transplants performed with postmortem NRP and 117 with SRR. The median donor age was 56 years (interquartile range 45-65 years). After IPTW analysis, baseline covariates were balanced, with all absolute standardised differences <0.15. IPTW-adjusted risks were significantly improved among NRP livers for overall biliary complications (odds ratio 0.14; 95% CI 0.06-0.35, p <0.001), ischaemic type biliary lesions (odds ratio 0.11; 95% CI 0.02-0.57; p = 0.008), and graft loss (hazard ratio 0.39; 95% CI 0.20-0.78; p = 0.008). CONCLUSIONS: The use of postmortem NRP in cDCD liver transplantation appears to reduce postoperative biliary complications, ischaemic type biliary lesions and graft loss, and allows for the transplantation of livers even from cDCD donors of advanced age. LAY SUMMARY: This is a propensity-matched nationwide observational cohort study performed using livers recovered from donors undergoing cardiac arrest provoked by the intentional withdrawal of life support (controlled donation after circulatory death, cDCD). Approximately half of the livers were recovered after a period of postmortem in situ normothermic regional perfusion, which restored warm oxygenated blood to the abdominal organs, whereas the remainder were recovered after rapid preservation with a cold solution. The study results suggest that the use of postmortem normothermic regional perfusion helps reduce rates of post-transplant biliary complications and graft loss and allows for the successful transplantation of livers from older cDCD donors.

Low Serum Melatonin Levels Prior to Liver Transplantation in Patients with Hepatocellular Carcinoma are Associated with Lower Survival after Liver Transplantation.

Melatonin administration has been associated with different benefits in animals and patients suffering from liver diseases. However, there is no published data about circulating melatonin levels in patients with hepatocellular carcinoma (HCC) who underwent liver transplantation (LT). Thus, the objective of this observational and retrospective study was to determine whether patients with HCC with lower serum melatonin levels prior to LT have a higher risk of one-year mortality after LT. We measured serum levels of melatonin, malondialdehyde (to assess lipid peroxidation), and total antioxidant capacity (to assess antioxidant state) before LT. One-year surviving LT patients (n = 129) showed higher serum levels of melatonin (p = 0.001) and total antioxidant capacity (p = 0.001) and lower serum levels of malondialheyde (p = 0.01) than non-surviving LT patients (n = 16). Logistic regression analysis showed that high serum melatonin levels prior to LT were associated with lower one-year LT mortality (odds ratio = 0.525; 95% confidence interval (CI) = 0.331⁻0.834; p = 0.006). We found an association between serum levels of melatonin with serum levels of malondialheyde (rho = -0.22; p = 0.01) and total antioxidant capacity (rho = 0.21; p = 0.01). Thus, the novel findings of our study were the association between high serum melatonin levels prior to LT and survival at first year after LT and the association between serum levels of melatonin with malondialheyde and total antioxidant capacity.

Directions for the Advancement of Culturally Adapted Preventive Interventions: Local Adaptations, Engagement, and Sustainability.

To advance the implementation and dissemination of culturally adapted interventions to diverse populations, greater attention should be devoted to three underdeveloped topics: (a) local adaptations of interventions when they are implemented in community settings, (b) participant engagement, and (c) the sustainability of adapted interventions. Several typologies have been developed for studying local adaptations, and some research indicates that such adaptations might add to intervention effectiveness. There is suggestive evidence of ethnocultural group disparities in intervention engagement and in the success of efforts to boost engagement. Theory and limited data indicate that interventions' flexibility and fit with organizational culture and resources can be achieved through cultural adaptations. Furthermore, those adaptations should be associated with sustainability, but research has yet to test that hypothesis adequately. Several recommendations are made for advancing culturally adapted interventions through additional research on local adaptations during implementation, the many facets of participant engagement, and sustainability.

Association between Pre-Transplant Serum Malondialdehyde Levels and Survival One Year after Liver Transplantation for Hepatocellular Carcinoma.

Previous studies have found higher levels of serum malondialdehyde (MDA) in hepatocellular carcinoma (HCC) patients compared to healthy controls and higher MDA concentrations in tumoral tissue of HCC patients than in non-tumoral tissue. However, the association between pre-transplant serum levels of MDA and survival in HCC patients after liver transplantation (LT) has not been described, and the aim of the present study was to determine whether such an association exists. In this observational study we measured serum MDA levels in 127 patients before LT. We found higher pre-LT serum MDA levels in 15 non-surviving than in 112 surviving patients one year after LT (p = 0.02). Exact binary logistic regression analysis revealed that pre-LT serum levels of MDA over 3.37 nmol/mL were associated with mortality after one year of LT (Odds ratio = 5.38; 95% confidence interval (CI) = from 1.580 to infinite; p = 0.007) adjusting for age of the deceased donor. The main finding of our study was that there is an association between serum MDA levels before LT for HCC and 1-year survival after LT.

Prognostic Value of Serum Caspase-Cleaved Cytokeratin-18 Levels before Liver Transplantation for One-Year Survival of Patients with Hepatocellular Carcinoma.

Cytokeratin (CK)-18 is the major intermediate filament protein in the liver and during hepatocyte apoptosis is cleaved by the action of caspases; the resulting fragments are released into the blood as caspase-cleaved cytokeratin (CCCK)-18. Higher circulating levels of CCCK-18 have been found in patients with hepatocellular carcinoma (HCC) than in healthy controls and than in cirrhotic patients. However, it is unknown whether serum CCCK-18 levels before liver transplantation (LT) in patients with HCC could be used as a prognostic biomarker of one-year survival, and this was the objective of our study with 135 patients. At one year after LT, non-survivors showed higher serum CCCK-18 levels than survivors (p = 0.001). On binary logistic regression analysis, serum CCCK-18 levels >384 U/L were associated with death at one year (odds ratio = 19.801; 95% confidence interval = 5.301-73.972; p < 0.001) after controlling for deceased donor age. The area under the receiver operating characteristic (ROC) curve of serum CCCK-18 levels to predict death at one year was 77% (95% CI = 69%-84%; p < 0.001). The new finding of our study was that serum levels of CCCK-18 before LT in patients with HCC could be used as prognostic biomarker of survival.

Relative contributions of naturalistic and constructed support: two studies of women with type 2 diabetes.

Do distinct sources of social support have differential effects on health? Although previous research has contrasted family and friend support (naturalistic support), research on the relative effects of naturalistic support and constructed support (e.g., support groups) is extremely rare. Two studies of women with type 2 diabetes were conducted that assessed the independent effects of naturalistic and constructed support on physical activity and glycosylated hemoglobin (HbA1c). Participants were women diagnosed with type 2 diabetes from the intervention arms of two randomized controlled trials: primarily European American women (Study 1; N = 163) and exclusively Hispanic women (Study 2; N = 142). Measures assessed physical activity, HbA1c, and friend and family support at baseline and at 6 months, as well as group support after 6 months of intervention. In Study 1, only group support was related to increases in physical activity (ΔR(2) = .036). In Study 2, group support and family support showed independent effects on increases in physical activity (ΔR(2) = .047 and .060, respectively). Also, group support was related to decreases in HbA1c in Study 1 (ΔR(2) = .031) and Study 2 (ΔR(2) = .065). Overall, constructed (group) support was related to outcomes most consistently, but naturalistic (family) support showed some independent relation to physical activity improvement.

Validation of the CALL score as a mortality prediction tool in a cohort of hospitalized COVID-19 patients in Chile.

Introduction: The CALL score is a predictive tool for respiratory failure progression in COVID-19. Whether the CALL score is useful to predict short- and medium-term mortality in an unvaccinated population is unknown. Materials and methods: This is a prospective cohort study in unvaccinated inpatients with a COVID-19 pneumonia diagnosis upon hospital admission. Patients were followed up for mortality at 28 days, 3, 6, and 12 months. Associations between CALL score and mortality were analyzed using logistic regression. The prediction performance was evaluated using the area under a receiver operating characteristic curve (AUROC). Results: A total of 592 patients were included. On average, the CALL score was 9.25 (±2). Higher CALL scores were associated with increased mortality at 28 days [univariate: odds ratio (OR) 1.58 (95% CI, 1.34-1.88), p < 0.001; multivariate: OR 1.54 (95% CI, 1.26-1.87), p < 0.001] and 12 months [univariate OR 1.63 (95% CI, 1.38-1.93), p < 0.001; multivariate OR 1.63 (95% CI, 1.35-1.97), p < 0.001]. The prediction performance was good for both univariate [AUROC 0.739 (0.687-0.791) at 28 days and 0.869 (0.828-0.91) at 12 months] and multivariate models [AUROC 0.752 (0.704-0.8) at 28 days and 0.862 (0.82-0.905) at 12 months]. Conclusion: The CALL score exhibits a good predictive capacity for short- and medium-term mortality in an unvaccinated population.

Patients with hepatocellular carcinoma that die during the first year of liver transplantation have high blood sFasL concentrations.

BACKGROUND: Fas ligand (FasL) is one ligand that activates extrinsic apoptosis pathway. High expression in lymphocytes of FasL have been found in patients with acute rejection of liver transplantation (LT). No high blood concentrations of soluble FasL (sFasL) have been found in patients with acute LT rejection; however, the samples size of those studies was small. AIM: To determine whether patients with hepatocellular carcinoma (HCC) that dead during the first year of LT have higher blood sFasL concentrations previously to LT that those who that remain alive in a study of higher sample size. METHODS: Patients underwent LT due to HCC were included in this retrospective study. Serum sFasL levels prior to LT were measured and one-year LT mortality was registered. RESULTS: Non-surviving patients (n = 14) showed higher serum sFasL levels [477 (269-496) vs 85 (44-382) pg/mL; P < 0.001] than surviving patients (n = 113). Serum sFasL levels (pg/mL) were associated with mortality (OR = 1.006; 95%CI = 1.003-1.010; P = 0.001) independently of age of LT donor in the logistic regression analysis. CONCLUSION: We report for the first time that HCC patients who die within the first year of HT have higher blood sFasL concentrations prior to HT than those who remain alive.

Persistence and Use of Ixekizumab in Patients with Psoriatic Arthritis in Real-World Practice in Spain. The PRO-STIP Study.

INTRODUCTION: Ixekizumab (IXE) is an IgG4-type monoclonal antibody targeting IL-17A indicated alone or in combination with methotrexate, for the treatment of active psoriatic arthritis (PsA) in adult patients with insufficient response or with intolerance to one or more disease-modifying anti-rheumatic drug (DMARD) therapy. The PRO-STIP study aimed to describe persistence, patient characteristics, treatment patterns, and effectiveness in patients with PsA receiving IXE in a real-world clinical setting in Spain. METHODS: This was an observational, multicentric, retrospective, longitudinal study in adult PsA patients who started IXE between January 2019 and December 2020, with at least 24 weeks of follow-up. A descriptive analysis of patient characteristics and treatment patterns was performed. The primary objective, treatment persistence, was estimated by Kaplan-Meier survival curve. Effectiveness was evaluated by Disease Activity in Psoriatic Arthritis (DAPSA) scores at baseline and at 12 and 24 weeks. RESULTS: Eighty-nine patients met the selection criteria (55.1% women and mean age 51.5 years). The median time from PsA diagnosis to starting IXE was 7.7 years (IQR 3.4-14.6). Prior to IXE, 95.5% patients had been treated with at least one biologic or targeted synthetic DMARD (b/tsDMARD). The observed persistence rates were 95.5%, 84.3% and 68.5% at 24, 48, and 104 weeks, respectively. The median persistence was not reached in the study period (mean persistence, 86.9 [95% CI 80.6-93.2] weeks). Twenty-eight (31.5%) patients discontinued IXE, 19 patients (21.3%) due to loss of effectiveness and two patients (2.2%) due to adverse events. In patients receiving treatment and with available effectiveness assessment (n = 24), DAPSA decreased significantly from baseline 23.7 (95% CI 19.5-27.9) to 14.8 (95% CI 10.5-19.2) at 12 weeks (p = 0.005) and 14.3 (95% CI 11.1-17.4) at 24 weeks (p = 0.004). CONCLUSIONS: PsA patients treated with IXE in a real-world setting show high treatment persistence through 104 weeks and improvements in disease activity after treatment initiation. This suggests that IXE could be an effective treatment for patients with PsA. RETROSPECTIVELY REGISTERED: Date of registration: 25th May 2021.

Unveiling Hidden Risks: Intentional Molecular Screening for Sexually Transmitted Infections and Vaginosis Pathogens in Patients Who Have Been Exclusively Tested for Human Papillomavirus Genotyping.

Human papillomavirus (HPV) is the most prevalent sexually transmitted infection (STI) worldwide, with popular screening methods including the Papanicolaou test and HPV genotyping. However, in clinical practice, coinfections with other pathogens are often underestimated. Therefore, our study aims to describe the prevalence of STIs and vaginosis in urogenital samples from patients who had been tested exclusively for HPV genotyping. METHODS: This analytical, prospective, cross-sectional study included 408 males and females. Eligible participants had positive and negative HPV genotyping test results and agreed to early detection or had HPV antecedents. They provided the same urogenital samples used for HPV detection and, through our multiplex in-house PCR assay, we screened for Candida spp., Ureaplasma spp., Trichomonas vaginalis, Neisseria gonorrhoeae, Chlamydia trachomatis, herpes simplex virus 1 and 2 (HSV), Mycoplasma spp., molluscum contagiosum virus (MCV), Treponema pallidum, Haemophilus spp., Staphylococcus aureus, and Klebsiella spp. The subsequent statistical analysis aimed to reveal correlations between HPV genotypes and the identified pathogens. RESULTS: Of the participants, 72.1% (n = 294) tested positive for HPV genotypes. HR-HPV (high-risk HPV) genotypes comprised 51 (8.1%), 66 (7.1%), and 58 (6.1%). Haemophilus spp., Ureaplasma spp., Candida spp., Staphylococcus aureus, and Mycoplasma spp. frequently co-occurred with HPV infection (p < 0.05). Gender-based variations were notorious for Ureaplasma spp., Mycoplasma spp., and MCV (p < 0.05). Coinfections were prevalent (43.9%), with a positive HPV result elevating the risk for Trichomonas vaginalis, Mycoplasma spp., Staphylococcus aureus, HSV, and MCV (OR > 1, p < 0.05). HPV 16 correlated with HSV and Ureaplasma spp., while HPV 6 was linked with HSV and MCV (p < 0.05). CONCLUSIONS: This screening strategy uncovered significant coinfections and associations between HPV genotypes and pathogens, underscoring the importance of routine screening to explore clinical implications in urogenital health.

Cost-effectiveness of upper extremity dry needling in the rehabilitation of patients with stroke.

INTRODUCTION: Dry needling (DN) has been shown to be effective for the treatment of upper extremity hypertonia in patients with stroke. PURPOSE: To evaluate the cost-effectiveness of DN in patients with stroke. METHODS: A cost-effectiveness analysis was performed in a research study conducted at a Spanish public hospital where patients were classified into two groups with or without DN. Hypertonia was measured using the Modified Modified Ashworth Scale (MMAS), and quality of life (QOL) was assessed using the EuroQoL 5-dimension questionnaire. Data regarding the effects and costs of physiotherapy were presented by calculating the mean and 95% confidence interval. The health outcomes were evaluated considering the rate of responders to the treatment based on the MMAS. Spanish preference weights were used to estimate quality-adjusted life years (QALYs). The incremental cost-effectiveness ratio (ICER) and incremental cost-utility ratio (ICUR) were calculated to determine the economic value of DN. RESULTS: Eighty patients with stroke in the subacute stage of recovery were selected to participate in this study. Based on the rate of responders, the ICER of the DN group was very low. Despite the sensitivity analysis performed, the results of the ICUR were not encouraging. DISCUSSION: Cost-effectiveness with responder rate results were favourable for the DN group and were confirmed by the sensitivity analysis according to levels of care. In addition, our findings revealed that 4 weeks of treatment could be more cost-effective than 8 weeks. DN treatment of the upper extremity appears to be cost-effective based on the rate of responders measured using the MMAS scale.

DNA and RNA oxidative damage in hepatocellular carcinoma patients and mortality during the first year of liver transplantation.

BACKGROUND: Oxidative damage of DNA and RNA has been associated with mortality of patients with different diseases. However, there is no published data on the potential use of DNA and RNA oxidative damage to predict the prognosis of patients with hepatocellular carcinoma (HCC) undergoing liver transplantation (LT). AIM: To determine whether patients with increased DNA and RNA oxidative damage prior to LT for HCC have a poor LT prognosis. METHODS: Patients with HCC who underwent LT were included in this observational and retrospective study. Serum levels of all three oxidized guanine species (OGS) were measured prior to LT since guanine is the nucleobase that forms DNA and RNA most prone to oxidation. LT mortality at 1 year was the end-point study. RESULTS: Surviving patients (n = 101) showed lower serum OGS levels (P = 0.01) and lower age of the liver donor (P = 0.03) than non-surviving patients (n = 13). An association between serum OGS levels prior to LT and 1-year LT (odds ratio = 2.079; 95% confidence interval = 1.356-3.189; P = 0.001) was found in the logistic regression analysis. CONCLUSION: The main new finding was that high serum OGS concentration prior to LT was associated with the mortality 1 year after LT in HCC patients.

A comparative study of treatment interventions for patellar tendinopathy: a secondary cost-effectiveness analysis.

OBJECTIVE: To compare the cost-effectiveness of three patellar tendinopathy treatments. DESIGN: Secondary (cost-effectiveness) analysis of a blinded, randomised controlled trial, with follow-up at 10 and 22 weeks. SETTINGS: Recruitment was performed in sport clubs. The diagnosis and the intervention were carried out at San Jorge University. PARTICIPANTS: The participants were adults between 18 and 45 years (n = 48) with patellar tendinopathy. INTERVENTIONS: Participants received percutaneous needle electrolysis, dry needling or sham needling, all of which were combined with eccentric exercise. MAIN OUTCOME MEASURES: Costs, quality-adjusted life years and incremental cost-effectiveness ratio were calculated for each group. RESULTS: The total cost per session was similar in the three groups: €9.46 for the percutaneous needle electrolysis group; €9.44 for the dry needling group; and €8.96 for the sham group. The percutaneous needle electrolysis group presented better cost-effectiveness in terms of quality-adjusted life years and 96% and 93% probability of being cost-effective compared to the sham and dry needling groups, respectively. CONCLUSION: Our study shows that percutaneous needle electrolysis has a greater probability of being cost-effective than sham or dry needling treatment.

Recent Differentiation of Aquatic Bacterial Communities in a Hydrological System in the Cuatro Ciénegas Basin, After a Natural Perturbation.

Pozas Rojas is a hydrological system comprising nine isolated shallow ponds and a deep lagoon, which were temporally merged in 2010 by increased rainfall due to a tropical cyclone. In this work, we assess which components, biotic interactions, or environment filtering effects, drive the assembly of microbial communities after a natural perturbation. Arsenic, pH, and temperature are among the most significant environmental variables between each pond, clustering the samples in two main groups, whereas microbial composition is diverse and unique to each site, with no core at the operational taxonomic unit level and only 150 core genera when studied at the genus level. Los Hundidos lagoon has the most differentiated community, which is highly similar to the epipelagic Mediterranean Sea communities. On the other hand, the shallow ponds at the Pozas Rojas system resemble more to epicontinental hydrological systems, such as some cold rivers of the world and the phreatic mantle from Iowa. Overall, despite being a sole of water body 2 years prior to the sampling, interspecific interactions, rather than environmental selection, seem to play a more important role in Pozas Rojas, bolstered by founder effects on each poza and subsequent isolation of each water body.