The c.415C>T polymorphism in NUDT15 is more frequent than the polymorphisms in TPMT in Chilean patients who use thiopurine drugs.

Azathioprine (AZA) and 6-mercaptopurine (6-MP) are drugs widely used in the treatment of autoimmune diseases. Among the enzymes involved in the metabolism of AZA and 6-MP are thiopurine methyltransferase (TPMT) and nudix hydrolase 15 (NUDT15). The existence of single nucleotide polymorphisms in the genes that code for these enzymes could decreased enzymatic activity AND lead to severe myelosuppression. The most relevant polymorphism is NUDT15*3 (rs116855232), where the replacement of cytosine for thymine at position 415, which in turn leads to a loss of enzymatic activity. In a previous study, it was identified that together the polymorphisms in the TPMT gene reach an allelic frequency of 3.81%. There is no information regarding the rs116855232 polymorphism in the NUDT15 gene, so this corresponds to the objective of this report. Blood samples from Chilean adult patients with indications for the use of AZA or 6-MP for different pathologies and who had undergone a TPMT gene polymorphism study were retrospectively analyzed. A total of 253 blood samples were analyzed. Of the 253 patients, 47 presented the c.415C>T polymorphism in the NUDT15 gene, 3 being homozygous and 44 heterozygous. Four of the heterozygous patients for NUDT15 also had the *3A variant in the TPMT gene, also heterozygous. The allelic frequency of the minor T allele found (9.88%) was very similar to that found in patients of Asian origin, and much higher than that reported for the European Caucasian or Latin American population.

Eccentric Cycling Is an Alternative to Nordic Hamstring Exercise to Increase the Neuromuscular Function of Knee Flexors in Untrained Men.

ABSTRACT: Valdes, O, Inzulza, S, Collao, N, Garcia-Vicencio, S, Tufano, JJ, Earp, J, Venegas, M, and Peñailillo, L. Eccentric cycling is an alternative to Nordic hamstring exercise to increase the neuromuscular function of knee flexors in untrained men. J Strength Cond Res 37(11): 2158-2166, 2023-Nordic hamstring exercise (NHE) has been proposed to reduce knee flexor (KF) injuries. However, submaximal alternatives to NHE are necessary for the clinical or weaker population. The aim of this study was to compare the effects of Nordic hamstring training (NHT) and eccentric cycling (ECC) training on the neuromuscular function of the KF. Twenty healthy men (27.7 ± 3.5 years) were randomly assigned into 2 groups that performed 10 training sessions (2-3 sessions·week-1) of either NHT (n = 10) or ECC (n = 10). Maximal voluntary isometric contraction of the KF and knee extensor (KE) muscles (MVICKF and MVICKE) was measured, and the hamstring/quadriceps strength (H/Q) ratio was calculated. Furthermore, changes in NHE maximum reaction force (NHE-MRFKF), NHE break-point angle (NHE-BPA), and muscle activity of the semitendinosus (STEMG) and biceps femoris (BFEMG) during the NHE after the interventions were compared. Although no group × time effects were observed (p = 0.09-0.70), but time effects were found for all variables. Pairwise comparisons revealed that MVICKF (+16.9%; p = 0.02), H/Q ratio (+11.8%; p = 0.01), NHE-MRFKF (+19.8%; p = 0.005), and NHE-BPA (+30.8%; p = 0.001) increased after ECC, whereas NHE-MRFKF (+9.7%; p = 0.003), NHE-BPA (+35.5%; p = 0.0002), and STEMG (+33.7%; p = 0.02) increased after NHT. A group × time effect was observed (p = 0.003) in BFEMG, revealing an increase only after ECC (+41.1%; p < 0.0001). Similar neuromuscular adaptations were found after both training modalities. Therefore, ECC provides similar adaptations as NHT and may serve as an alternative form of KF training for those unable to perform NHE.

Liver transplantation in acute liver failure due to Hepatitis B. Two clinical cases.

Hepatitis B virus (HBV) related acute liver failure (ALF) is uncommon in our region, and there is limited HBV literature regarding the optimal management of these cases. In this article, we report two clinical cases of young men who have sex with men (MSM), both developed severe acute hepatitis caused by HBV, progressed to ALF and afterward required liver transplantation. Antiviral post-transplant treatment included entecavir without Hepatitis B Immunoglobulin (HBIG), and immunosuppression therapy with steroids, tacrolimus, and mycophenolate. Serologic follow-up showed early Hepatitis B surface Antigen (HBsAg) seroconversion, undetectable HBV viral load, and positive Anti-HBs titers. During later follow-up, Anti-HBs titers gradually fell (<10mUI/L after six months), with normal liver function. DISCUSSION: In cases of HBV-related ALF, the liver develops a robust immune response, leading to, an early undetectable viral load and seroconversion, with loss of HBsAg, and the appearance of Anti-HBs as a result of the inflammatory response. The management varies depending on whether this is a de novo acute infection or a reactivation of a previous chronic infection. In both cases, the use of antiviral therapy is recommended, with entecavir or tenofovir, among others, but the use of specific HBIG is supported only in ALF related to chronic HBV infection. The optimal length of the antiviral therapy after liver transplantation is still under discussion. CONCLUSION: These cases of HBV related ALF with an early HBsAg seroconversion demonstrates the relevance of requesting IgM antibody against hepatitis B core antigen (anti-HBc IgM) for the etiological study of ALF with negative HBsAg. Usage of HBIG does not seem essential during the post-transplantation period in these cases.

[Acute hepatitis C. Report of seven cases]. / Hepatitis aguda por virus C: reporte de siete casos en centro de referencia en Chile.

Hepatitis C virus infection is a major global public health problem. Treatment with direct-acting antivirals is intended to eradicate the chronic form of this infection by 2030. Although uncommon, the acute form of presentation is increasingly recognized, especially in some high-risk populations, such as men who have sex with men without protection. Its virological and serological diagnosis is not standardized, so clinical suspicion is essential. Its early detection allows a timely treatment. We report seven cases of acute HCV hepatitis in a national reference center, its presentation, diagnosis and treatment. We discuss populations at risk and the change in therapeutics with the use of direct-acting antiviral drugs.

Effects of sympathectomy on ovarian follicular development and steroid secretion.

Recently, the influence of adrenergic activity over ovarian function, and thus fertility, has begun to gain importance. Previous studies have shown that adrenergic activity through norepinephrine (NE) participates in the control of follicular development and steroidal secretion from the ovary, among other functions. To examine this phenomenon, the denervation of the gonad has been widely used to observe changes in the ovary's performance. Nevertheless, the effect of the absence of adrenergic nerves in the ovary has only been studied in short times periods. In the present work, we used guanethidine (a drug that produces an irreversible sympathectomy) during the infantile period of rats, and we observed its effects in the adult rat (6 months old). Our results indicate that ovarian NE content is recovered at 6 months old, alongside with an increase of the adrenal content of NE and a dysfunctional celiac ganglion. Together, these results suggest that the recovery of ovarian NE does not come from a neural origin. In addition, ovarian performance was impaired because the changes in follicular development and steroidal secretion are not recovered despite the recovery of ovarian NE content. In conclusion, these results suggest that the nerve-ovarian connections, which are established during infantile development, are necessary for the accurate response of the ovary to sympathetic stimulation.

[Interferon Lambda 4 RS12979860 C>T polymorphism is not associated with liver fibrosis in patients with hepatitis C]. / El polimorfismo rs12979860 C>T en el gen Interferón lambda 4 no está asociado a riesgo de fibrosis hepática en pacientes chilenos con hepatitis crónica por virus C.

BACKGROUND: Host genetic predispositions may be important determinants of liver fibrosis in patients with chronic hepatitis C (CHC). The association between Interferon-L 4 (IFNL4) rs12979860 C>T polymorphism and risk of liver fibrosis in CHC is contradictory. AIM: To evaluate the impact of IFNL4 rs12979860 polymorphism on the risk of fibrosis in patients with CHC. MATERIAL AND METHODS: One hundred fifty patients with CHC aged 50 ± 11 years (89 females) were genotyped for IFNL4 rs12979860 using real time PCR. Fibrosis present in liver biopsies was assessed using the METAVIR score, comparing patients with either no fibrosis, mild fibrosis, or intermediate fibrosis (F0+F1+F2, n = 96), with patients with severe fibrosis or cirrhosis (F3+F4, n = 54). RESULTS: In F0-F2 patients the distribution of rs12979860 genotypes was 22 CC, 57 CT and 17 TT, whereas in patients F3-F4 the distribution was 10, 29 and 15, respectively. No association between IFNL4 rs12979860 genotype and risk of fibrosis was observed in uni or multivariate analyses. CONCLUSIONS: IFNL4 rs12979860 C>T polymorphism is not associated with risk of liver fibrosis in this group of patients with CHC.

Replication of a chronic hepatitis B virus genotype F1b construct.

Genotype F is one of the less-studied genotypes of human hepatitis B virus, although it is widely distributed in regions of Central and South American. Our previous studies have shown that HBV genotype F is prevalent in Chile, and phylogenetic analysis of its full-length sequence amplified from the sera of chronically infected patients identified it as HBV subgenotype F1b. We have previously reported the full-length sequence of a HBV molecular clone obtained from a patient chronically infected with genotype F1b. In this report, we established a system to study HBV replication based on hepatoma cell lines transfected with full-length monomers of the HBV genome. Culture supernatants were analyzed after transfection and found to contain both HBsAg and HBeAg viral antigens. Consistently, fractionated cell extracts revealed the presence of viral replication, with both cytoplasmic and nuclear DNA intermediates. Analysis of HBV-transfected cells by indirect immunofluorescence or immunoelectron microscopy revealed the expression of viral antigens and cytoplasmic viral particles, respectively. To test the functionality of the ongoing viral replication further at the level of chromatinized cccDNA, transfected cells were treated with a histone deacetylase inhibitor, and this resulted in increased viral replication. This correlated with changes posttranslational modifications of histones at viral promoters. Thus, the development of this viral replication system for HBV genotype F will facilitate studies on the regulation of viral replication and the identification of new antiviral drugs.

[Spontaneous clearance of hepatitis C virus after liver transplantation: Report of two cases]. / Eliminación espontánea de virus hepatitis C en trasplantado hepático: a propósito de dos casos.

The spontaneous clearance of hepatitis C virus infection is rare, especially after liver transplantation, condition in which recurrence is almost universal. We report two cases in which clearance of the virus was achieved after liver transplantation. We reviewed the literature and described possible mechanisms explaining this phenomenon, with emphasis on therapeutic implications.

[Hepatitis E virus seroprevalence: a reappraisal]. / Re-evaluación de seroprevalencia de virus hepatitis E.

Reported seroprevalence of hepatitis E virus (HEV) in developed countries is between 0.3-53%. Published data relies on the assays used and its technical performance. Sensitivity on new available tests has improved, which has changed HEV seroprevalence around the world. We re-evaluated retrospectively, 178 serum samples of patients with previous anti HEV IgG determination between 2009 and 2012. Initial analysis was performed with ELISA kit Genelabs (Singapore), with 7.3% positivity. The reevaluation was done with ELISA kit AccuDiag TM HEV-IgG (Diagnostic Automation, United States), with reported sensitivity and specificity over 99.8%. With the new assay, 32.6% positive samples were found, significantly greater to the previous result (p<0.001) (4.5 times more). There were no differences in gender but a significant association between age and HEV IgG seropositivity was found (p<0.001). This suggests that previous testing might have underestimated HEV seroprevalence in Chile, which should be reevaluated using the new available test.

[National and regional distribution of hepatitis C virus genotypes in Chile]. / Distribución nacional y regional de genotipos del virus hepatitis C en Chile.

Genotyping of hepatitis C virus has an important prognostic value for response to antiviral therapy. The results of hepatits C virus genotyping performed between 1994 and 2012 from 1,766 patients of different regions of Chile are reported. Global genotype (Gt) distribution was as follows: 7.87% Gt1a, 72.71% Gt1b, 1.98% Gt2, 16.53% Gt3a, 0.57% Gt4, 0.28% Gt5a and 0.06% Gt6. In most regions the genotype distribution was similar to the global. However, there were some differences, in particular in the south of our country, where 3a is present in more than 30% in some regions.

Genomic determinants of hepatitis C virus antiviral therapy outcomes: toward individualized treatment.

Hepatitis C virus (HCV) is an important global health problem with an estimated prevalence of more than 170 million infected individuals worldwide. Currently, the standard antiviral therapy, based on pegylated interferon alpha and ribavirin, can achieve a virological response in only nearly 50% of the patients infected with HCV genotype 1, the most widely distributed globally. During the last years, relevant data from genome-wide association studies (GWAS) about the impact and contribution of the patient genomics on viral infection outcomes has suggested the possibility that an individualized antiviral therapy can be considered. In this review, we analyze the existing information on single nucleotide polymorphisms (SNPs) of several host genes and viral factors that influence, as a whole, the outcome of the standard antiviral therapy, and that might be used to predict an individualized antiviral response. We also discuss the clinical data within the most recent context of the triple antiviral therapy.

[Hepatitis B virus immunoglobulin on demand to prevent infection recurrence among liver allograft recipients: report of three cases]. / Trasplante hepático en cirrosis por virus B: profilaxis con gammaglobulina antiHBs en dosis a "demanda".

Infection recurrence rates among hepatitis B virus infected liver allograft recipients, may be as high as 80%. Immunoprophylaxis with anti HBVgammaglobulin may reduce these rates and improve survival. The dose of anti HBV gammaglobulin that must be used is not clearly defined. The most commonly accepted protocol uses 10,000 units during the anhepatic phase and 10,000 units daily during one week, followed by weekly doses of 10,000 units during one month and maintenance with 10,000 units monthly, without measuring anti hepatitis B surface antigen antibodies (antiHBs). Some reports recommend the use of immunoglobulin on demand, to maintain antiHBs titers between 100 and 250 U/l. The infection recurrence rates among patients treated with immunoglobulin and Lamivudine fluctuates between 0 and 10%, during follow up periods of 13 to 30 months. We report three liver allograft recipients that received immunoglobulin on demand, using a mean of 41,000 units, maintaining adequate antiHBs titers.

Phylogenetic analysis of hepatitis B virus genotype F complete genome sequences from Chilean patients with chronic infection.

Molecular epidemiological data concerning the hepatitis B virus (HBV) in Chile are not known completely. Since the HBV genotype F is the most prevalent in the country, the goal of this study was to obtain full HBV genome sequences from patients infected chronically in order to determine their subgenotypes and the occurrence of resistance-associated mutations. Twenty-one serum samples from antiviral drug-naive patients with chronic hepatitis B were subjected to full-length PCR amplification, and both strands of the whole genomes were fully sequenced. Phylogenetic analyses were performed along with reference sequences available from GenBank (n = 290). The sequences were aligned using Clustal X and edited in the SE-AL software. Bayesian phylogenetic analyses were conducted by Markov Chain Monte Carlo simulations (MCMC) for 10 million generations in order to obtain the substitution tree using BEAST. The sequences were also analyzed for the presence of primary drug resistance mutations using CodonCode Aligner Software. The phylogenetic analyses indicated that all sequences were found to be the HBV subgenotype F1b, clustered into four different groups, suggesting that diverse lineages of this subgenotype may be circulating within this population of Chilean patients.

[Results of treatment with peginterferon plus ribavirin in patients with chronic hepatitis C]. / Resultados del tratamiento con peginterferón alfa-2a y ribavirina en pacientes con hepatitis crónica C.

BACKGROUND: The current treatment recommendation for chronic hepatitis C virus infection is the combination of peginterferon and ribavirin for 24 or 48 weeks, depending on the viral genotype. The aim of the therapy is to obtain a sustained virological response. AIM: To report our experience in the treatment of chronic hepatitis C. MATERIAL AND METHODS: Analysis of 52 patients treated between September 2000 and June 2009. Patients with genotype 1 or 5 were treated with peginterferon alpha 2a (180 ug/week) and ribavirin (1000 mg/day for those weighing less than 75 kg and 1200 mg/day for those weighing more than 75 kg) during 48 weeks. Patients with genotypes 2 and 3 were treated for 24 weeks with the same dose of peginterferon and ribavirin 800 mg/day. RESULTS: Viral genotypes 1, 2, 3 and 5 were present in 81, 4, 11 and 4% of patients, respectively. Twenty four patients (46 %), 18 with genotype 1, achieved a sustained viral response. Age was the only variable that influenced the response to treatment. CONCLUSIONS: Approximately half of the patients with chronic hepatitis C, achieve a sustained viral response with peginterferon and ribavirin.

[Comparison between Xpert® and COBAS® TaqMan® for the measuring of viral load of hepatitis B and C viruses]. / Comparación entre Xpert® y COBAS®-TaqMan® para la medición de carga viral de virus hepatitis B y C.

BACKGROUND: The measurement of viral load (VL) of hepatitis B (HBV) and C (HCV) viruses is essential in the follow-up of patients with antiviral therapy. The most widely used methodology for this determination is COBAS®-TaqMan®. Recently, the Xpert® technology was developed and needs to be evaluated. AIM: To compare the measurement of the VL of HBV and HCV by Xpert® methodology with COBAS®-TaqMan® as a reference method. MATERIAL AND METHODS: 39 serum samples from patients with HBV and 39 with HCV, previously quantified by COBAS®-TaqMan®, were analyzed using Xpert® and the results were compared using Deming regression and Bland-Altman plot. RESULTS: There was a high correlation between Xpert® and COBAS®-TaqMan®. For HBV, the Deming equation was XpertHBV = 0.44 + 0.99xCOBASTaqManHBV, with a correlation coefficient of 0.94 and a difference between means of -0.401 log (95% CI: -1.985 to 1.183). For HCV, the Deming equation was XpertHCV = 0.36 + 0.87x COBASTaqManHCV, with a correlation coefficient of 0.98 and a difference between means of0.328 log10 (95% CI: -0.449 to 1.105). CONCLUSION: The new Xpert® system shows a good correlation with COBAS®-TaqMan® for the measurement of the VL of HBV and HCV, being a good alternative for the follow-up of patients under treatment.

[Detection of anti-virus hepatitis e IgG and IgM antibodies using an automated method: experience of a university hospital]. / Detección de anticuerpos anti virus hepatitis E IgG e IgM utilizando un método automatizado: experiencia de un hospital universitario.

The determination of anti-hepatitis E virus antibodies (anti-HEV) has a high variability depending on the assay used. In 2015, with a manual ELISA method, we reported anti-HEV IgG seroprevalence of 32.6% in patients under hepatitis study. There are few reports of anti-HEV IgM. Recently, it was developed the first automated method and in the present study, we report the experience using this new method. Between May 2018 and August 2020, the results of 272 patients with an anti-HEV IgG and/or IgM study were analyzed using the automated ELFA technique (VIDAS®). Seroprevalence was 25.8% (68/264) for anti-HEV IgG and 3.5% (9/259) for anti-HEV IgM. Four samples were positive for both antibodies. Anti-HEV IgG seropositivity increased with age. In conclusion, the seroprevalence of anti-HEV IgG obtained was similar to previously reported. Taking into account the advantages of these assays, anti-HEV IgM and IgG assays on VIDAS® system, seem to be valuable new tools in serological study of HEV.

Haloterrigena sp. Strain SGH1, a Bacterioruberin-Rich, Perchlorate-Tolerant Halophilic Archaeon Isolated From Halite Microbial Communities, Atacama Desert, Chile.

An extreme halophilic archaeon, strain SGH1, is a novel microorganism isolated from endolithic microbial communities colonizing halites at Salar Grande, Atacama Desert, in northern Chile. Our study provides structural, biochemical, genomic, and physiological information on this new isolate living at the edge of the physical and chemical extremes at the Atacama Desert. SGH1 is a Gram-negative, red-pigmented, non-motile unicellular coccoid organism. Under the transmission electron microscope, strain SGH1 showed an abundant electro-dense material surrounding electron-lucent globular structures resembling gas vacuoles. Strain SGH1 showed a 16S rRNA gene sequence with a close phylogenetic relationship to the extreme halophilic archaea Haloterrigena turkmenica and Haloterrigena salina and has been denominated Haloterrigena sp. strain SGH1. Strain SGH1 grew at 20-40°C (optimum 37°C), at salinities between 15 and 30% (w/v) NaCl (optimum 25%) and growth was improved by addition of 50 mM KCl and 0.5% w/v casamino acids. Growth was severely restricted at salinities below 15% NaCl and cell lysis is avoided at a minimal 10% NaCl. Maximal concentrations of magnesium chloride and sodium or magnesium perchlorates that supported SGH1 growth were 0.5 and 0.15M, respectively. Haloterrigena sp. strain SGH1 accumulates bacterioruberin (BR), a C50 xanthophyll, as the major carotenoid. Total carotenoids in strain SGH1 amounted to nearly 400 µg BR per gram of dry biomass. Nearly 80% of total carotenoids accumulated as geometric isomers of BR: all-trans-BR (50%), 5-cis-BR (15%), 9-cis-BR (10%), 13-cis-BR (4%); other carotenoids were dehydrated derivatives of BR. Carotenogenesis in SGH1 was a reversible and salt-dependent process; transferring BR-rich cells grown in 25% (w/v) NaCl to 15% (w/v) NaCl medium resulted in depigmentation, and BR content was recovered after transference and growth of unpigmented cells to high salinity medium. Methanol extracts and purified BR isomers showed an 8-9-fold higher antioxidant activity than Trolox or ß-carotene. Both, plasma membrane integrity and mitochondrial membrane potential measurements under acute 18-h assays showed that purified BR isomers were non-toxic to cultured human THP-1 cells.

Prevalence of hepatitis B virus genotypes in chronic carriers in Santiago, Chile.

The eight genotypes (designated A-H) of hepatitis B virus (HBV) display distinctive geographical distribution worldwide, with genotypes A, D and F frequently detected in South America. To determine the prevalence of HBV genotypes in Santiago, Chile, 131 samples from chronic carriers were used for PCR amplification, and genotyping was performed by RFLP. The results indicated that genotype F was the most prevalent among HBV carries (84% of the cases), whereas genotypes A, B, C and D were found at a prevalence of 3.8, 3.8, 6.1, and 2.3%, respectively. We discuss these data in the complex scenario of HBV epidemiology.

[Hepatitis E virus seroprevalence in blood donors in a university hospital in Chile]. / Seroprevalencia de virus hepatitis E en donantes de sangre en un hospital universitario en Chile.

In Chile, there are few studies about seroprevalence of IgG antibodies against hepatitis E virus (HEV) in blood banks, between 4 and 8%. The development of new techniques with greater sensitivity and specificity, account for an increase in the seroprevalence of HEV in various countries, the current status in Chile being unknown. In the present study, we determined the seroprevalence of anti-HEV IgG in blood donors of the Clinical Hospital University of Chile, with last generation ELISA techniques. Out of a total of 186 samples, collected in 2014, 56 (30.1%) were positive, without gender differences, but with a significant increase with age (p < 0.001). These results show an increase in the seroprevalence of HEV in blood donors performed with immunoassays of greater sensitivity.

Ex situ culture of coral species Porites lobata (Scleractinia: Poritidae) and Pocillopora damicornis (Scleractinia: Pocilloporidae), Costa Rica: first assessment and implications

Introduction: Coral reefs worldwide decline has prompted coral restoration as a viable strategy to rewild vulnerable, foundational coral species. Stony corals are now propagated by thousands in both in-water and ex situ (land-based) coral nurseries, the latter being unexplored in Costa Rica, despite their potential benefits as a reef management tool. Objective: To analyze the viability of ex situ culturing of the Pacific reef-building corals Porites lobata and Pocillopora damicornis at Parque Marino del Pacífico (PMP), Puntarenas, Costa Rica, aquaculture facilities. Methods: From May to October 2018 a total of 180 coral fragments were kept in an aquaculture recirculated system. Survival, growth, and fragment yield in relation to culture medium (physicochemical parameters) were recorded. Results: Survival and growth rate varied between species and culture tanks. On average, surviving P. lobata fragments (68.89 %) placed in Tank 1 (T1) grew 216 %, while fragments placed in Tank 2 (T2) had a survival rate of 71.11 % and an increase of 277 % in live tissue area. P. damicornis fragments survival, basal and crown area percentage increase were: 71.11 %, 980 % and 366 % in T1, and 100 %, 976 % and 287 % in T2. Although fragments survival and growth were net positive, the yield in terms of culture was low, due to culture conditions in the tanks not meeting coral culture optimal requirements. Conclusions: Survival and growth of both species varied depending on the tank in which they were placed. Survival was similar to that found in other ex situ studies and growth was similar to those reported in the wild, however culture performance in terms of yield was low. Aquaculture systems at PMP constitute a good base for the cultivation of corals, however for the culture effort to achieve maximum yield, current systems must be optimized according to the requirements of the target coral species.

Introducción: El declive mundial de los arrecifes de coral, ha impulsado a la restauración coralina como una estrategia viable para recuperar especies de coral fundacionales, en estado vulnerable. Los corales pétreos se propagan por miles, tanto en viveros subacuáticos como ex situ (en tierra). Siendo el segundo método poco explorado en Costa Rica, a pesar de sus potenciales beneficios como medida como herramienta de manejo arrecifal. Objetivo: Analizar la viabilidad del cultivo ex situ de las especies de coral constructoras de arrecifes Porites lobata y Pocillopora damicornis en el módulo de acuicultura del Parque Marino del Pacífico (PMP), Puntarenas, Costa Rica. Métodos: Desde el 17 de mayo hasta el 17 de octubre de 2018, se mantuvieron un total de 180 fragmentos de coral en un sistema de recirculación de acuicultura. Se registraron la supervivencia, el crecimiento y el rendimiento de los fragmentos en relación con el medio de cultivo (parámetros fisicoquímicos). Resultados: La tasa de supervivencia y crecimiento varió entre especies y tanques de cultivo. En promedio, los fragmentos de P. lobata supervivientes (68.89 %) colocados en el tanque 1 (T1) crecieron un 216 %. En contraste con los fragmentos colocados en el tanque 2 (T2) que mostraron una tasa de supervivencia del 71.11 % y un aumento del 277 % en el área de tejido vivo. En el caso de P. damicornis, los porcentajes de supervivencia, de aumento del área basal y del área de la corona fueron: 71.11 %, 980 %, y 366 %, y 100 %, 976 %, y 287 % para los fragmentos colocados en T1 y T2, respectivamente. Aunque la supervivencia y el crecimiento de los fragmentos fueron positivos, el rendimiento en términos de cultivo fue bajo, debido a que las condiciones en los tanques no cumplían con las condiciones ideales para el cultivo de corales. Conclusiones: La supervivencia y el crecimiento de ambas especies variaron en función del tanque en el que se colocaron. La supervivencia fue similar a la observada en otros estudios ex situ y el crecimiento fue similar al reportado en la naturaleza, pero el rendimiento del cultivo fue bajo. Los sistemas de acuicultura del PMP constituyen una buena base para el cultivo de corales, sin embargo, para que el esfuerzo de cultivo alcance un máximo de rendimiento, los sistemas actuales deben optimizarse en función de los requisitos de las especies de coral objetivo.