The IRE1α-XBP1 arm of the unfolded protein response is a host factor activated in SARS-CoV-2 infection.

SARS-CoV-2 infection can cause severe pneumonia, wherein exacerbated inflammation plays a major role. This is reminiscent of the process commonly termed cytokine storm, a condition dependent on a disproportionated production of cytokines. This state involves the activation of the innate immune response by viral patterns and coincides with the biosynthesis of the biomass required for viral replication, which may overwhelm the capacity of the endoplasmic reticulum and drive the unfolded protein response (UPR). The UPR is a signal transduction pathway composed of three branches that is initiated by a set of sensors: inositol-requiring protein 1 (IRE1), protein kinase RNA-like ER kinase (PERK), and activating transcription factor 6 (ATF6). These sensors control adaptive processes, including the transcriptional regulation of proinflammatory cytokines. Based on this background, the role of the UPR in SARS-CoV-2 replication and the ensuing inflammatory response was investigated using in vivo and in vitro models of infection. Mice and Syrian hamsters infected with SARS-CoV-2 showed a sole activation of the Ire1α-Xbp1 arm of the UPR associated with a robust production of proinflammatory cytokines. Human lung epithelial cells showed the dependence of viral replication on the expression of UPR-target proteins branching on the IRE1α-XBP1 arm and to a lower extent on the PERK route. Likewise, activation of the IRE1α-XBP1 branch by Spike (S) proteins from different variants of concern was a uniform finding. These results show that the IRE1α-XBP1 system enhances viral replication and cytokine expression and may represent a potential therapeutic target in SARS-CoV-2 severe pneumonia.

Risk scores for predicting incident heart failure admission in patients with chronic coronary syndromes: Validation in a prospective, monocentric, long-term, cohort study.

BACKGROUND: Heart failure (HF) admission in chronic coronary syndrome (CCS) patients has a prognostic impact. Stratification schemes have been described for predicting this endpoint, but none of them has been externally validated. OBJECTIVES: Our aim was to develop point scores for predicting incident HF admission with data from previous studies, to perform an external validation in an independent prospective cohort and to compare their discriminative ability for this event. METHODS: Independent predictive variables of HF admission in CCS patients without baseline HF were selected from four previous prospective studies (CARE, PEACE, CORONOR and CLARIFY), generating scores based on the relative magnitude of the coefficients of Cox of each variable. Finally, the scores were validated and compared in a monocentric prospective cohort. RESULTS: The validation cohort included 1212 patients followed for up to 17 years, with 171 patients suffering at least one HF admission in the follow-up. Discriminative ability for predicting HF admission was statistically significant for all, and paired comparisons among them were all nonsignificant except for CORONOR score was superior to CLARIFY score (C-statistic 0.73, 95%CI 0.69-0.76 vs. 0.69, 95% CI 0.65-0.73; p = 0.03). CONCLUSION: All tested scores showed significant discriminative ability for predicting incident HF admission in this independent validation study. Their discriminative ability was similar, with significant differences only between the two scores with higher and lower performance.

Fungal Patterns Induce Cytokine Expression through Fluxes of Metabolic Intermediates That Support Glycolysis and Oxidative Phosphorylation.

Cytokine expression is fine-tuned by metabolic intermediates, which makes research on immunometabolism suitable to yield drugs with a wider prospect of application than the biological therapies that block proinflammatory cytokines. Switch from oxidative phosphorylation (OXPHOS) to glycolysis has been considered a characteristic feature of activated immune cells. However, some stimuli might enhance both routes concomitantly. The connection between the tricarboxylic acid cycle and cytokine expression was scrutinized in human monocyte-derived dendritic cells stimulated with the fungal surrogate zymosan. Results showed that nucleocytosolic citrate and ATP-citrate lyase activity drove IL1B, IL10, and IL23A expression by yielding acetyl-CoA and oxaloacetate, with the latter one supporting glycolysis and OXPHOS by maintaining cytosolic NAD+ and mitochondrial NADH levels through mitochondrial shuttles. Succinate dehydrogenase showed a subunit-specific ability to modulate IL23A and IL10 expression. Succinate dehydrogenase A subunit activity supported cytokine expression through the control of the 2-oxoglutarate/succinate ratio, whereas C and D subunits underpinned cytokine expression by conveying electron flux from complex II to complex III of the electron transport chain. Fatty acids may also fuel the tricarboxylic acid cycle and influence cytokine expression. Overall, these results show that fungal patterns support cytokine expression through a strong boost of glycolysis and OXPHOS supported by the use of pyruvate, citrate, and succinate, along with the compartmentalized NAD(H) redox state maintained by mitochondrial shuttles.

Supervivencia a largo plazo de una población española con cardiopatía isquémica estable: el registro CICCOR / Long-term survival in a Spanish population with stable ischemic heart disease. The CICCOR registry

Introducción y objetivos: La información sobre el pronóstico de la cardiopatía isquémica crónica (CIC) es escasa. El objetivo es analizar los predictores de la mortalidad y la supervivencia a largo plazo de estos pacientes. Métodos: Estudio de cohortes prospectivo y monocéntrico que reclutó a 1.268 pacientes con CIC desde enero de 2000 hasta febrero de 2004. Se registraron los fallecimientos durante el seguimiento. Se compararon las tasas de mortalidad total y cardiovascular ajustadas con la población española. Se investigó la asociación de variables basales con la mortalidad. Resultados: La media de edad fue 68+/-10 años; el 73% eran varones. Tras 17 años de seguimiento máximo (mediana, 11 años), murieron 629 pacientes (50%). La edad (HR=1,08; IC95%, 1,07-1,11; p<0,001), la diabetes (HR=1,36; IC95%, 1,14-1,63; p <0,001), la frecuencia cardiaca (HR=1,01; IC95%, 1,00-1,02; p <0,001), la fibrilación auricular (HR=1,61; IC95%, 1,22-2,14); p=0,001), las alteraciones electrocardiográficas (HR=1,23; IC95%, 1,02-1,49; p=0,02) y el tabaquismo (HR=1,85; IC95%, 1,31-2,80; p=0,001) han resultado predictores independientes de la mortalidad total. La tasa de mortalidad total fue mayor que en la población española (47,81 frente a 36,29/1.000 pacientes/año; razón de mortalidad estandarizada=1,31; IC95%, 1,21-1,41). La tasa de mortalidad cardiovascular fue 15,25 frente a 6,94/1.000 pacientes/año de la población general (razón de mortalidad estandarizada=2,19; IC95%, 1,88-2,50). Conclusiones: En esta muestra de pacientes con CIC, la tasa de mortalidad fue significativamente mayor que en la población general. Las variables clínicas identifican a los pacientes con mayor riesgo de muerte en el seguimiento

Introduction and objectives: Data are lacking on the long-term prognosis of stable ischemic heart disease (SIHD). Our aim was to analyze long-term survival in patients with SIHD and to identify predictors of mortality. Methods: A total of 1268 outpatients with SIHD were recruited in this single-center prospective cohort study from January 2000 to February 2004. Cardiovascular and all-cause death during follow-up were registered. All-cause and cardiovascular mortality rates were compared with those in the Spanish population adjusted by age, sex, and year. Predictors of these events were investigated. Results: The mean age was 68+/-10 years and 73% of the patients were male. After a follow-up lasting up to 17 years (median 11 years), 629 (50%) patients died. Independent predictors of all-cause mortality were age (HR, 1.08; 95%CI, 1.07-1.11; P <.001), diabetes (HR, 1.36; 95%CI, 1.14-1.63; P <.001), resting heart rate (HR, 1.01; 95%CI, 1.00-1.02; P <.001), atrial fibrillation (HR, 1.61; 95%CI, 1.22-2.14; P=.001), electrocardiographic changes (HR, 1.23; 95%CI, 1.02-1.49; P=.02) and active smoking (HR, 1.85; 95%CI, 1.31-2.80; P=.001). All-cause mortality and cardiovascular mortality rates were significantly higher in the sample than in the general Spanish population (47.81/1000 patients/y vs 36.29/1000 patients/y (standardized mortality rate, 1.31; 95%CI, 1.21-1.41) and 15.25/1000 patients/y vs 6.94/1000 patients/y (standardized mortality rate, 2.19; 95%CI, 1.88-2.50, respectively). Conclusions: The mortality rate was higher in this sample of patients with SIHD than in the general population. Several clinical variables can identify patients at higher risk of death during follow-up

Tricarboxylic Acid Cycle Activity and Remodeling of Glycerophosphocholine Lipids Support Cytokine Induction in Response to Fungal Patterns.

Increased glycolysis parallels immune cell activation, but the role of pyruvate remains largely unexplored. We found that stimulation of dendritic cells with the fungal surrogate zymosan causes decreases of pyruvate, citrate, itaconate, and α-ketoglutarate, while increasing oxaloacetate, succinate, lactate, oxygen consumption, and pyruvate dehydrogenase activity. Expression of IL10 and IL23A (the gene encoding the p19 chain of IL-23) depended on pyruvate dehydrogenase activity. Mechanistically, pyruvate reinforced histone H3 acetylation, and acetate rescued the effect of mitochondrial pyruvate carrier inhibition, most likely because it is a substrate of the acetyl-CoA producing enzyme ACSS2. Mice lacking the receptor of the lipid mediator platelet-activating factor (PAF; 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine) showed reduced production of IL-10 and IL-23 that is explained by the requirement of acetyl-CoA for PAF biosynthesis and its ensuing autocrine function. Acetyl-CoA therefore intertwines fatty acid remodeling of glycerophospholipids and energetic metabolism during cytokine induction.

Spiralyde A, an Antikinetoplastid Dolabellane from the Brown Alga Dictyota spiralis.

Bioassay-guided fractionation of the antikinetoplastid extract of the brown alga Dictyota spiralis has led to the isolation of spiralyde A (1), a new dolabellane aldehyde, along with other five known related diterpenes (2⁻6). Their structures were determined by HRESIMS, 1D and 2D NMR spectroscopy, and comparison with data reported in the literature. The antiparasitic activity of all compounds was evaluated. Spiralyde A (1) and the known compound 3,4-epoxy-7,18-dolabelladiene (2) were the most active compounds against Leishmania amazonensis and Trypanosoma cruzi. Spiralyde A (1) was the most potent compound, comparable to benznidazole, the reference drug for trypanocidal activity.

Sclerin, a New Cytotoxic Cyclononapeptide from Annona scleroderma.

A new cytotoxic cyclononapeptide, sclerin, cyclo(⁻Dab¹â»Ser²â»Tyr³â»Gly4⁻Thr5⁻Val6⁻Ala7⁻ Ile8⁻Pro8⁻) (1), was isolated from the methanol extract of the seeds of Annona scleroderma, together with the known metabolite, cyclosenegalin A, cyclo(⁻Pro¹â»Gly²â»Leu³â»Ser4⁻Ala5⁻Val6⁻Thr7⁻) (2). The planar structures for the two compounds were established by comprehensive analysis of NMR and ESI-HRMS data, and the absolute stereochemistry was stablished by Marfey's method. Compound 1 showed moderate cytotoxic activity against the human prostate carcinoma cell line DU-145 at µM concentration.

Long-term Survival in a Spanish Population With Stable Ischemic Heart Disease. The CICCOR Registry.

INTRODUCTION AND OBJECTIVES: Data are lacking on the long-term prognosis of stable ischemic heart disease (SIHD). Our aim was to analyze long-term survival in patients with SIHD and to identify predictors of mortality. METHODS: A total of 1268 outpatients with SIHD were recruited in this single-center prospective cohort study from January 2000 to February 2004. Cardiovascular and all-cause death during follow-up were registered. All-cause and cardiovascular mortality rates were compared with those in the Spanish population adjusted by age, sex, and year. Predictors of these events were investigated. RESULTS: The mean age was 68±10 years and 73% of the patients were male. After a follow-up lasting up to 17 years (median 11 years), 629 (50%) patients died. Independent predictors of all-cause mortality were age (HR, 1.08; 95%CI, 1.07-1.11; P <.001), diabetes (HR, 1.36; 95%CI, 1.14-1.63; P <.001), resting heart rate (HR, 1.01; 95%CI, 1.00-1.02; P <.001), atrial fibrillation (HR, 1.61; 95%CI, 1.22-2.14; P=.001), electrocardiographic changes (HR, 1.23; 95%CI, 1.02-1.49; P=.02) and active smoking (HR, 1.85; 95%CI, 1.31-2.80; P=.001). All-cause mortality and cardiovascular mortality rates were significantly higher in the sample than in the general Spanish population (47.81/1000 patients/y vs 36.29/1000 patients/y (standardized mortality rate, 1.31; 95%CI, 1.21-1.41) and 15.25/1000 patients/y vs 6.94/1000 patients/y (standardized mortality rate, 2.19; 95%CI, 1.88-2.50, respectively). CONCLUSIONS: The mortality rate was higher in this sample of patients with SIHD than in the general population. Several clinical variables can identify patients at higher risk of death during follow-up.

The toxic benthic dinoflagellate Prorocentrum maculosum Faust is a synonym of Prorocentrum hoffmannianum Faust.

Three strains of the toxic benthic dinoflagellate Prorocentrum hoffmannianum were isolated in the Canary Islands (north-east Atlantic Ocean, Spain). The identity of the strains was determined by phylogenetic analyses of partial LSU rDNA (D1-D2 regions) but their morphology based on SEM images corresponded to P. maculosum. Their toxin profiles were analyzed by liquid chromatography and high resolution mass spectrometry analysis (LC-HRMS) on cell extracts and culture media. Okadaic acid and three analogs were detected in all strains. Rather, in culture media the detected compounds were variable among strains, two of them being okadaic acid analogs not found on cell extracts. As a result, the taxonomy of the species was revised and P. maculosum is proposed as a junior synonym of P. hoffmannianum whose description is emended.

Marine Longilenes, Oxasqualenoids with Ser-Thr Protein Phosphatase 2A Inhibition Activity.

The red seaweed Laurencia viridis is a rich source of oxygenated secondary metabolites that were derived from squalene. We report here the structures of three novel compounds, (+)-longilene peroxide (1), longilene (2), and (+)-prelongilene (3) that were isolated from this alga, in addition to other substances, 4 and 5, resulting from their acid-mediated degradation. The effect of compounds 1 and 3 against Ser-Thr protein phosphatase type 2A (PP2A) was evaluated, showing that (+)-longilene peroxide (1) inhibited PP2A (IC50 11.3 μM). In order to explain the interaction between PP2A and compounds 1 and 3, molecular docking simulations onto the PP2A enzyme-binding region were used.

Endoplasmic Reticulum Stress Sensor IRE1α Enhances IL-23 Expression by Human Dendritic Cells.

Human monocyte-derived dendritic cells (DCs) exposed to pathogen-associated molecular patterns (PAMPs) undergo bioenergetic changes that influence the immune response. We found that stimulation with PAMPs enhanced glycolysis in DCs, whereas oxidative phosphorylation remained unaltered. Glucose starvation and the hexokinase inhibitor 2-deoxy-d-glucose (2-DG) modulated cytokine expression in stimulated DCs. Strikingly, IL23A was markedly induced upon 2-DG treatment, but not during glucose deprivation. Since 2-DG can also rapidly inhibit protein N-glycosylation, we postulated that this compound could induce IL-23 in DCs via activation of the endoplasmic reticulum (ER) stress response. Indeed, stimulation of DCs with PAMPs in the presence of 2-DG robustly activated inositol-requiring protein 1α (IRE1α) signaling and to a lesser extent the PERK arm of the unfolded protein response. Additional ER stressors such as tunicamycin and thapsigargin also promoted IL-23 expression by PAMP-stimulated DCs. Pharmacological, biochemical, and genetic analyses using conditional knockout mice revealed that IL-23 induction in ER stressed DCs stimulated with PAMPs was IRE1α/X-box binding protein 1-dependent upon zymosan stimulation. Interestingly, we further evidenced PERK-mediated and CAAT/enhancer-binding protein ß-dependent trans-activation of IL23A upon lipopolysaccharide treatment. Our findings uncover that the ER stress response can potently modulate cytokine expression in PAMP-stimulated human DCs.

Clinical and radiological control of highly active relapsing-remitting multiple sclerosis with first-line natalizumab.

A 33-year-old man with gait instability, weakness of the left lower extremity, decreased visual acuity in the left eye, and urgency and urine incontinence was diagnosed of relapsing-remitting multiple sclerosis. He was treated with natalizumab (300 mg intravenously every 4 weeks) as first-line therapy, which reached at 6 months a favorable clinical evolution and dramatic radiological improvement (T2-weighted lesion load decreased by 50% and no gadolinium-enhancing T1 lesions) sustained over the course of 8 years. This clinical case shows the efficacy of natalizumab in a real-world setting and, particularly, the sustained effect of this drug in the long term as demonstrated by persistent radiological improvement. Natalizumab can be considered as the treatment of choice in relapsing-remitting multiple sclerosis forms presenting with two relapses and gadolinium-enhancing (Gd+) lesions.

I-AUV Docking and Panel Intervention at Sea.

The use of commercially available autonomous underwater vehicles (AUVs) has increased during the last fifteen years. While they are mainly used for routine survey missions, there is a set of applications that nowadays can be only addressed by manned submersibles or work-class remotely operated vehicles (ROVs) equipped with teleoperated arms: the intervention applications. To allow these heavy vehicles controlled by human operators to perform intervention tasks, underwater structures like observatory facilities, subsea panels or oil-well Christmas trees have been adapted, making them more robust and easier to operate. The TRITON Spanish founded project proposes the use of a light-weight intervention AUV (I-AUV) to carry out intervention applications simplifying the adaptation of these underwater structures and drastically reducing the operational cost. To prove this concept, the Girona 500 I-AUV is used to autonomously dock into an adapted subsea panel and once docked perform an intervention composed of turning a valve and plugging in/unplugging a connector. The techniques used for the autonomous docking and manipulation as well as the design of an adapted subsea panel with a funnel-based docking system are presented in this article together with the results achieved in a water tank and at sea.

Prevalencia de la esclerosis múltiple en la Región de Murcia / Prevalence of multiple sclerosis in the Region of Murcia

Introducción. La esclerosis múltiple (EM) es una enfermedad inflamatoria desmielinizante del sistema nervioso central con patogenia inmunomediada. Recientes estudios indican un aumento de su prevalencia, y numerosos trabajos relacionan el virus de Epstein-Barr (VEB) con su etiología. Objetivo. Análisis de prevalencia de la EM en la Región de Murcia, incluyendo la descripción de las características clínicas en el momento del inicio de la enfermedad, y del estado serológico del VEB de los pacientes con EM. Pacientes y métodos. Estudio epidemiológico retrospectivo, tomando como muestra la población residente en el área sanitaria centro-oeste de la Región de Murcia (257.865 habitantes). Se analizan datos clínicos y serológicos extraídos de diferentes fuentes. Resultados. Prevalencia de la EM en la población estudiada: 88 casos/100.000 habitantes. Prevalencia de la EM junto con el síndrome desmielinizante aislado: 98,4 casos/100.000 habitantes. Incidencia media de la EM: 5,8 casos/100.000 habitantes/año. En el inicio de la EM, el 67,8% eran mujeres, el 81,9% presentaba un curso recurrente-remitente, la edad media era de 31,4 años, el sistema funcional más frecuentemente afectado era el sensitivo (45,1%), el inicio fue monofocal en el 55,4% y el grado de discapacidad en la Expanded Disability Status Scale era de 2,1 puntos. La seroprevalencia del VEB fue del 99,3%. La reactivación de la infección por VEB se relacionó con actividad clínica de EM en 10 pacientes (45,4%). Conclusiones. Actualmente, la prevalencia de la EM en la Región de Murcia es similar a la estimada en otras comunidades autónomas españolas. El estudio confirma la tendencia de incremento de prevalencia observada en las últimas décadas (AU)

Introduction. Multiple sclerosis (MS) is a demyelinating inflammatory disease of the central nervous system with immunemediated pathogenesis. Recent research points to an increase in its prevalence, and a number of studies relate EpsteinBarr virus (EBV) with its aetiology. Aims. This study seeks to analyse the prevalence of MS in the Region of Murcia, and includes a description of the clinical characteristics at the time of onset of the disease, and of the EBV serological status of patients with MS. Patients and methods. We conducted a retrospective epidemiological study based on a sample consisting of the population living within the central-west healthcare area of the Region of Murcia (257,865 inhabitants). Clinical and serological data extracted from different sources were analysed. Results. Prevalence of MS in the population under study: 88 cases/100,000 inhabitants. Prevalence of MS together with isolated demyelinating syndrome: 98.4 cases/100,000 inhabitants. Mean incidence of MS: 5.8 cases/100,000 inhabitants/ year. At the onset of MS, 67.8% were females, 81.9% presented a relapsing-remitting course, the mean age was 31.4 years, the sensory system was the most frequently compromised (45.1%), onset was monofocal in 55.4% and the degree of disability on the Expanded Disability Status Scale was 2.1 points. The seroprevalence of EBV was 99.3%. The reactivation of EBV infection was related to the clinical activity of MS in 10 patients (45.4%). Conclusions. Currently, the prevalence of MS in the Region of Murcia is similar to that estimated in other Spanish autonomous regions. The study confirms the trend of increased prevalence observed over the last few decades (AU)

New oxidized zoanthamines from a Canary Islands Zoanthus sp.

Three new norzoanthamine-type alkaloids, named 2-hydroxy-11-ketonorzoan thamide B (1), norzoanthamide B (2) and 15-hydroxynorzoanthamine (3), were isolated from Zoanthus sp. specimens collected at the Canary Islands. Their structures were determined by interpretation of NMR and HR-ESIMS data. Relative configurations of their chiral centers were proposed on the basis of ROESY spectra and by comparison of their spectroscopic data with those of the well-known compound, norzoanthamine.

Prevalencia y riesgo anual de infeccion por tuberculosis en la población escolar de 7 años de edad de Ceuta / Prevalence and annual risk of tuberculosis infection in the school population aged 7 years old in Ceuta (Spain)

Objetivo Conocer la prevalencia de la infección tuberculosa y el riesgo anual de infección en la población escolar de Ceuta. Método Estudio transversal. Se realizó la prueba de la tuberculina (2UT RT-23 Tween 80) a los niños de 7 años de edad escolarizados en Ceuta en 2008. Se consideraron positivos los niños no vacunados con una induración ≥5mm a las 72 horas. Resultados Se estudiaron 612 niños. La prevalencia de la infección fue del 0,98% (intervalo de confianza del 95%, margen de error del 2,5%). Su distribución mostró diferencias entre las tres zonas de salud, y fue mayor en las zonas más deprimidas, donde llegó al 2,07%. El riesgo anual de infección fue del 0,15%.ConclusionesLa prevalencia de la infección es de las más altas de España, según los últimos estudios realizados. Los resultados no se corresponden con los datos epidemiológicos de tuberculosis de Ceuta, al tener en cuenta los casos importados (AU)

Objective To determine the prevalence of tuberculosis infection and annual risk of infection in the school population of Ceuta. Method A cross-sectional study was conducted. A tuberculin test (2UT RT-23 Tween 80) was given to 7-year-old schoolchildren in Ceuta in 2008. A positive result was considered as an induration of ≥5mm at 72hours in unvaccinated children. Results A total of 612 children were studied. The prevalence of tuberculosis infection was 0.98% (95% confidence interval with a 2.5% margin of error). The distribution showed differences among three health areas, and was greatest in the most deprived area (2.07%). The annual risk of infection was 0.15%.ConclusionsAccording to the most recent studies, the prevalence of tuberculosis infection in Ceuta is one of the highest of Spain. Our results do not agree with the epidemiological data for tuberculosis in Ceuta, which also includes imported cases(AU)

[Prevalence and annual risk of tuberculosis infection in the school population aged 7 years old in Ceuta (Spain)]. / Prevalencia y riesgo anual de infeccion por tuberculosis en la población escolar de 7 años de edad de Ceuta.

OBJECTIVE: To determine the prevalence of tuberculosis infection and annual risk of infection in the school population of Ceuta. METHOD: A cross-sectional study was conducted. A tuberculin test (2UT RT-23 Tween 80) was given to 7-year-old schoolchildren in Ceuta in 2008. A positive result was considered as an induration of ≥5 mm at 72 hours in unvaccinated children. RESULTS: A total of 612 children were studied. The prevalence of tuberculosis infection was 0.98% (95% confidence interval with a 2.5% margin of error). The distribution showed differences among three health areas, and was greatest in the most deprived area (2.07%). The annual risk of infection was 0.15%. CONCLUSIONS: According to the most recent studies, the prevalence of tuberculosis infection in Ceuta is one of the highest of Spain. Our results do not agree with the epidemiological data for tuberculosis in Ceuta, which also includes imported cases.

New polyether triterpenoids from Laurencia viridis and their biological evaluation.

The red seaweed Laurencia viridis is a rich source of secondary metabolites derived from squalene. New polyethers, such as iubol (2), 22-hydroxy-15(28)- dehydrovenustatriol (3), 1,2-dehydropseudodehydrothyrsiferol (4), and secodehydrothyrsiferol (5) have been isolated and characterized from this alga. The structures were determined through the interpretation of NMR spectroscopic data and the relative configuration was proposed on the basis of NOESY spectrum and biogenetic considerations. All new compounds exhibited significant cytotoxic activity against a panel of cancer cell lines.