The toxic dinoflagellate Alexandrium catenella adversely affects early life stages of tehuelche scallop.

The effects of the toxic dinoflagellate Alexandrium catenella were investigated on growth, survival, and histopathology in larvae and spat of the Tehuelche scallop Aequipecten tehuelchus from Patagonia, Argentina. The study consisted of laboratory incubations of scallop larvae/spat with A. catenella, using environmentally realistic abundances of the dinoflagellate. Survival, growth, and histopathological effects were documented for scallop larvae/spat before, during, and after 7-day-long exposure to A. catenella. The scallops were grouped in flasks containing 0 (control), 20, 200, and 2000 cells mL-1 of A. catenella. The presence of A. catenella induced reduced larvae survival after 24 h, whereas a clear effect was observed after 3 days (survival of control larvae 95%, 72, and 79% for 20 and 200 cells mL-1, respectively, and 43% for 2000 cells mL-1). The growth rates of the control larvae and those exposed to 20 mL-1 cells were significantly different from zero. Histopathological effects (melanization, loss of connective tissue, necrosis, and inflammatory responses) were observed in spat exposed to A. catenella. These effects were more pronounced at the highest dinoflagellate concentration. Blooms of A. catenella frequently coincide with the reproductive season of A. tehuelchus, thus there is a need to further study the relationship between harmful algal blooms and the effect on scallops' natural populations in the region.

Host-parasite relationship Octopus tehuelchus - Aggregata valdessensis in Patagonian coast, southwestern Atlantic Ocean.

Histopathology associated with the apicomplexan Aggregata valdessensis in the wild population of Octopus tehuelchus was studied. Moreover, to analyze the impact of the prevalence and infection intensity on the dorsal mantle length, sex, maturity stages, condition index and total hemocyte counts on wild O. tehuelchus, Generalized Linear Models (GLMs) were applied. Kruskal-Wallis (KW) test was used to compare growth parameter (RNA/DNA ratios) in infected and uninfected octopuses. Lesions including hypertrophy of host cells and destruction of the tissue organ architecture as well as the replacement of host tissue by parasites were associated with infection. The infection caused an inflammatory defensive response in form of hemocytic infiltration.. The prevalence of apicomplexan increased with octopus dorsal mantle length (GLM, t = 2.68; p = 0.007). Infection intensity was significantly higher in male octopus (GLM, t = 2.69; p = 0.009) and decreased at higher temperatures in both sexes (GLM, t = -2.42; p = 0.018). The digestive gland condition index did not significantly vary with infection intensity, and no significant relationship between total hemocyte counts and coccidian infection was found (Lineal Model, t = 0.46; p = 0.64). The acid nucleic ratio was significantly lower in octopuses infected by A. valdessensis (Kruskal Wallis test, H = 4.8; p = 0.02), suggesting a detrimental effect on O. tehuelchus growth caused by the coccidian.

Changing Trends in the Global Consumption of Treatments Used in Hospitalized Patients for COVID-19: A Time Series Multicentre Study.

AIM: To analyze trends in the prescription of COVID-19 treatments for hospitalized patients during the pandemic. METHODS: Multicenter, ecological, time-series study of aggregate data for all adult patients with COVID-19 treated in five acute-care hospitals in Barcelona, Spain, between March 2020 and May 2021. Trends in the monthly prevalence of drugs used against COVID-19 were analyzed by the Mantel-Haenszel test. RESULTS: The participating hospitals admitted 22,277 patients with COVID-19 during the study period, reporting an overall mortality of 10.8%. In the first months of the pandemic, lopinavir/ritonavir and hydroxychloroquine were the most frequently used antivirals, but these fell into disuse and were replaced by remdesivir in July 2020. By contrast, the trend in tocilizumab use varied, first peaking in April and May 2020, declining until January 2021, and showing a discrete upward trend thereafter. Regarding corticosteroid use, we observed a notable upward trend in the use of dexamethasone 6 mg per day from July 2020. Finally, there was a high prevalence of antibiotics use, especially azithromycin, in the first three months, but this decreased thereafter. CONCLUSIONS: Treatment for patients hospitalized with COVID-19 evolved with the changing scientific evidence during the pandemic. Initially, multiple drugs were empirically used that subsequently could not demonstrate clinical benefit. In future pandemics, stakeholders should strive to promote the early implementation of adaptive randomized clinical trials.

Comparative genomics for Agmasoma sp. (Microsporidia) parasitising invasive Carcinus aestuarii and Carcinus maenas in Argentina.

Carcinus spp. are global aquatic invaders and carriers of several parasites, including a taxonomically unrecognised microsporidian recently observed from Argentina. We provide genome drafts for two parasite isolates, one from Carcinus maenas and one from Carcinus aestuarii, and use multi-gene phylogenetics and genome comparison methods to outline their similarities. Their SSU genes are 100 % similar and other genes have an average similarity of 99.31 %. We informally name the parasite Agmasoma carcini, terming the isolates Ac. var. aestuarii and Ac. var. maenas, following the wealth of genomic data available for each. This study follows on from Frizzera et al. (2021), where this parasite was first histologically identified.

Persistent COVID-19 symptoms 1 year after hospital discharge: A prospective multicenter study.

OBJECTIVE: To determine the health status and exercise capacity of COVID-19 survivors one year after hospital discharge. METHODS: This multicenter prospective study included COVID-19 survivors 12 months after hospital discharge. Participants were randomly selected from a large cohort of COVID-19 patients who had been hospitalized until 15th April 2020. They were interviewed about persistent symptoms, underwent a physical examination, chest X-ray, and a 6-minute walk test (6MWT). A multivariate analysis was performed to determine the risk factors for persistent dyspnea. RESULTS: Of the 150 patients included, 58% were male and the median age was 63 (IQR 54-72) years. About 82% reported ≥1 symptoms and 45% had not recovered their physical health. The multivariate regression analysis revealed that the female sex, chronic obstructive pulmonary disease, and smoking were independent risk factors for persistent dyspnea. Approximately 50% completed less than 80% of the theoretical distance on the 6MWT. Only 14% had an abnormal X-ray, showing mainly interstitial infiltrates. A third of them had been followed up in outpatient clinics and 6% had undergone physical rehabilitation. CONCLUSION: Despite the high rate of survivors of the first wave of the COVID-19 pandemic with persistent symptomatology at 12 months, the follow-up and rehabilitation of these patients has been really poor. Studies focusing on the role of smoking in the persistence of COVID-19 symptoms are lacking.

A phylogenetically unresolved apicomplexan (APXSc) causing swirl lesions in the Tehuelche scallop, Aequipecten tehuelchus, from the Southwest Atlantic coast.

The study reports a previously unknown apicomplexan (APXSc) parasite infecting wild scallops Aequipecten tehuelchus (d'Orbigny, 1842) from two separate areas (La Tapera and Punta Conos) of the San José gulf, in Patagonia Argentina. Histology, transmission electron microscope, molecular analyses and in situ hybridization were performed to describe the morphology of APXSc, and confirm its phylogenetic status. The prevalence of APXSc infection was 24% and 72% in scallops from La Tapera and Punta Conos, respectively. Seasonal variation was observed for scallops from La Tapera, recording highest prevalence in summer. A positive relationship between the presence of the APXSc and the size of the scallops was observed. A SSU rDNA consensus sequence of 1758 base pairs was generated which has a 94.8% identity to sequences obtained from a pathogenic apicomplexan parasite infecting Ostrea chilensis in New Zealand, but not closely related to other apicomplexans. The asexual reproduction, i.e. merogony, occurs in the Tehuelche scallop whilst the gamogonic and sporogonic stages were absent, suggesting a yet unknown definitive host. Severe host inflammation response involving fibroblast-like hemocytes surrounding the APXSc in the form of granuloma-like "swirls" is characteristic for this apicomplexan infection. Further studies are needed to reveal the life cycle, and presumable pathogenicity of APXSc.

Long-term impact of COVID-19 associated acute respiratory distress syndrome.

OBJECTIVES: To determine the health status, exercise capacity, and health related quality of life (HRQoL) of COVID-19 associated acute respiratory distress syndrome (ARDS) survivors, 8 months after diagnosis. METHODS: All eligible patients were interviewed and underwent a physical examination, chest X-ray, and 6 min walk test (6MWT). Scales to evaluate post-traumatic stress disorder, depression, anxiety, and HRQoL were applied. RESULTS: Of 1295 patients, 365 suffered ARDS and 166 survived to hospital discharge. Five died after discharge and 48 were lost to follow-up. Of the 113 remaining patients, 81% had persistent symptoms. More than 50% of patients completed less than 80% of the theoretical distance on the 6MWT, 50% had an abnormal X-ray and 93% of patients developed psychiatric disorders. Mean SF-36 scores were worse than in the general population. After multivariate regression analysis, female sex, non-Caucasian race, and Charlson index>2 were independent risk factors for a worse mental health component summary score on the SF-36, and age was associated with a better prognosis. Female sex and chronic obstructive pulmonary disease were independently associated with a worse physical component summary score. CONCLUSION: COVID-19 associated ARDS survivors have long-term consequences in health status, exercise capacity, and HRQoL. Strategies addressed to prevent these sequelae are needed.

Symbionts of invasive and native crabs, in Argentina: The most recently invaded area on the Southwestern Atlantic coastline.

Biological invasions have the capacity to introduce non-native parasites. This study aimed to determine whether the invasive green crab population, Carcinus spp., on the Southwestern Atlantic coast of Argentina harbours any symbionts, and whether these may spillover or spillback between native crabs, Cyrtograpsus altimanus and C. angulatus. Macroscopy, histology, and molecular analyses of some parasites were used to describe and compare their diversity across the three species of crab. We also evaluated the susceptibility of invasive Carcinus spp. to a native digenean, Maritrema madrynense, via experimental infections (exposure and cohabitation). Our results revealed that the green crab pathobiome included similar symbiotic groups to native crabs. This included putative viral, bacterial, and protozoan parasites. Haplosporidium-like observations were recorded in all crab species, and a single green crab was found to be parasitized by an Agmasoma-like microsporidium. Metagenomic analysis of one individual revealed additional symbiotic diversity (46 bacteria, 5 eukaryotic species). The green crabs were infected by more microparasite taxa than the native crabs (5:3). Wild populations of Carcinus spp. were free of metazoan parasites and are shown not to be susceptible to M. madryense under experimental conditions. Our results suggest a reduction/escape of macroparasites (trematode Maritrema madrynense; acanthocephalan Profilicollis chasmagnathi) in invasive Carcinus spp. compared to their native competitors.

A single clonal lineage of transmissible cancer identified in two marine mussel species in South America and Europe.

Transmissible cancers, in which cancer cells themselves act as an infectious agent, have been identified in Tasmanian devils, dogs, and four bivalves. We investigated a disseminated neoplasia affecting geographically distant populations of two species of mussels (Mytilus chilensis in South America and M. edulis in Europe). Sequencing alleles from four loci (two nuclear and two mitochondrial) provided evidence of transmissible cancer in both species. Phylogenetic analysis of cancer-associated alleles and analysis of diagnostic SNPs showed that cancers in both species likely arose in a third species of mussel (M. trossulus), but these cancer cells are independent from the previously identified transmissible cancer in M. trossulus from Canada. Unexpectedly, cancers from M. chilensis and M. edulis are nearly identical, showing that the same cancer lineage affects both. Thus, a single transmissible cancer lineage has crossed into two new host species and has been transferred across the Atlantic and Pacific Oceans and between the Northern and Southern hemispheres.

First detection of Ostreid herpesvirus 1 in wild Crassostrea gigas in Argentina.

Ostreid herpesvirus 1 (OsHV-1) is a DNA virus of the genus Ostreavirus (Malacoherpesviridae family, Herpesvirales order). Worldwide, OsHV-1 and its microvariants have been associated with increased mortality of Pacific oysters, Crassostrea gigas. Adult asymptomatic oysters also have shown a high prevalence of viral infection. As a consequence, surveillance is needed to better describe OsHV-1 diversity, pathogenicity, clinical signs, and geographical distribution. We examined Crassostrea gigas sampled in October 2017 from the inner zone of the Bahía Blanca Estuary, Argentina, and found that 8 of 30 specimens (26.7%) presented macroscopic lesions in mantle tissues. Histological analysis revealed abnormal presentation of mantle epithelial cells and connective tissues. Conventional and real-time PCR conducted on the oyster samples revealed 70% to be positive for presence of OsHV-1 DNA. The nucleotide sequence of the amplicon obtained from one sample using the primer pair IA1/IA2 (targeting ORF 42/43) was 99% identical to OsHV-1 reference as well as µVar strains B and A (KY271630, KY242785.1), sequenced from France and Ireland. This finding represents the first detection of OsHV-1 DNA in a wild population of C. gigas in Argentina in association with gross mantle lesions.

Parasites in two coexisting bivalves of the Patagonia coast, southwestern Atlantic Ocean: The Puelche oyster (Ostrea puelchana) and false oyster (Pododesmus rudis).

The purpose of this study was to compare the parasites of two coexisting bivalves, the edible Puelche oyster (Ostrea puelchana) and the false oyster (Pododesmus rudis) that lives attached to O. puelchana shells, and to investigate their host specificity. Samples from wild populations, 465 O. puelchana and 131 P. rudis, were collected seasonally during two years in the San José Gulf (northern Patagonia, Argentina) and were processed using standard histological techniques. To increase the natural low prevalences of Bonamia spp. and Perkinsus spp. that are present in wild populations, an in situ experiment was performed by maintaining captive sentinel bivalves at high densities inside a plastic mesh bag to enhance parasite transmission. Polymerase chain reaction (PCR) assays were used to test for apparent Bonamia sp. infections among captive sentinel O. puelchana specimens (n = 80), and Ray's fluid thioglycollate medium (RFTM) assays and histological immunoassays tested for apparent Perkinsus sp. infections among captive sentinel P. rudis specimens (n = 100). Despite histological observations that revealed the presence of microcells resembling Bonamia sp. infecting hemocytes of some Puelche oysters, PCR assays did not confirm that parasite identification. Among captive sentinel P. rudis that showed histological evidence of Perkinsus sp. infections, neither RFTM nor immunoassays confirmed such parasites. Ostrea puelchana from wild populations were occasional hosts for both Rickettsia-like organism (RLOs) and Urastoma-like turbellarians. In contrast, six parasite taxa infected P. rudis from coexisting populations, including RLOs, Urastoma-like turbellarians, an intracellular gregarine species, Nematopsis-like oocysts, an unidentified coccidian and a Perkinsus qugwadi-like protozoan. These results demonstrated specific infection patterns of the identified parasites in relation to their hosts.

[Sequential treatment with Mitomycin C and BCG in non muscle invasive bladder cancer.] / Tratamiento secuencial con Mitomicina C y BCG en el cáncer vesical no músculo-invasivo.

Bacilus Calmette-Guerin (BCG) administered intravesical is an effective therapy in non muscle invasive bladder cancer (NMIBC), but it presents limitations regarding recurrence and toxicity. For years, many case series have been published where sequential therapy with BCG and Mitomycin C (MMC) was tried. In this article, we perform a review of the data supplied by these articles with the aim to determine the safety and efficacy of combination, and what is the group of patients it should be indicated. Many studies show that combination therapy did not cause more toxicity and improved the interval free of disease with decrease of tumor progression compared to BCG or MMC monotherapy. Therefore, a combination of MMC and BCG therapy seems safe, but more clinical studies are required for a future evaluation.

Tratamiento secuencial con Mitomicina C y BCG en el cáncer vesical no músculo-invasivo / Sequential treatment with Mitomycin C and BCG in non muscle invasive bladder cancer

El Bacilo de Calmette-Guerin (BCG) administrado por vía intravesical es una terapia eficaz en el Cáncer Vesical no Músculo Invasivo (CVNMI), pero presenta limitaciones en términos de recurrencia y toxicidad. Desde hace años se han publicado muchos artículos de series de pacientes donde se ha probado la terapia secuencial entre BCG y Mitomicina C (MMC). En este trabajo se realiza una revisión de los datos aportados por esos artículos con la finalidad de determinar la seguridad y eficacia de la combinación, y en qué grupo de pacientes estaría indicada. Muchos estudios indican que la terapia de combinación frente a la monoterapia con BCG o MMC no causó más toxicidades y mejoró el intervalo libre de enfermedad con disminución de la progresión tumoral. Por lo tanto, la combinación de tratamiento con MMC y BCG parece ser segura, mientras que aún se necesitan más estudios clínicos para una evaluación posterior

Bacilus Calmette-Guerin (BCG) administered intravesical is an effective therapy in non muscle invasive bladder cancer (NMIBC), but it presents limitations regarding recurrence and toxicity. For years, many case series have been published where sequential therapy with BCG and Mitomycin C (MMC) was tried. In this article, we perform a review of the data supplied by these articles with the aim to determine the safety and efficacy of combination, and what is the group of patients it should be indicated. Many studies show that combination therapy did not cause more toxicity and improved the interval free of disease with decrease of tumor progression compared to BCG or MMC monotherapy. Therefore, a combination of MMC and BCG therapy seems safe, but more clinical studies are required for a future evaluation

Estado actual de la telemedicina: ¿dónde estamos y qué nos queda por hacer? / State of the art of the telemedicine. Where are we and what is pending to be done?

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cis-Platinum Complex Encapsulated in Self-Assembling Cyclic Peptide Dimers.

A new cyclic peptide dimer that encapsulates cisplatin complexes in its internal cavity is described. The resulting complex showed cytotoxic activity at A2780 ovarian cancer cell lines independent of acquired platinum resistance.

Effect of tomato juice consumption on the plasmatic lipid profile, hepatic HMGCR activity, and fecal short chain fatty acid content of rats.

The aims of the present study were to ascertain, indirectly, the prebiotic role of tomato juice, by analyzing its effect on the content of short chain fatty acids (SCFA) in feces of rats, and to determine the plausible mechanisms related to the hypocholesterolemic effects of tomato juice and lycopene, evaluating the activity of hepatic HMGCR and the formation of propionic acid. Two commercially available tomato juices with differing contents of lycopene (low and high lycopene contents: Llyc and Hlyc tomato juices) were used. Sprague-Dawley male rats were randomly divided into three experimental groups (n = 8): control group, normal diet and water; group 1, normal diet and Llyc tomato juice; and group 2, normal diet and Hlyc tomato juice, which were fed ad libitum for three weeks. Feces were collected at the beginning and the end of the study to determine SCFA, and blood and liver were obtained (after sacrificing the animals) to analyze the lipid plasmatic parameters and the HMGCR activity and total cholesterol, respectively. No significant differences were observed in the plasmatic parameters, except that HDL-cholesterol increased significantly after consumption of both tomato juices. Lycopene was accumulated in the liver in proportion to the amount ingested, and was observed to have an inhibitory effect on the HMGCR enzyme, according to the amount of lycopene in the liver. In relation to the SCFA in feces, no differences were observed in acetate and propionate after the consumption of tomato juice, but a significant increase in butyrate was observed in group 2 after the intake of Hlyc tomato juice. The content of this carboxylic acid together with excreted lycopene in feces could have a beneficial effect on colonic cells.

Anion Recognition and Induced Self-Assembly of an α,γ-Cyclic Peptide To Form Spherical Clusters.

A cyclic octapeptide composed of hydroxy-functionalized γ-amino acids folds in a "V-shaped" conformation that allows the selective recognition of anions such as chloride, nitrate, and carbonate. The process involves the simultaneous self-assembly of six peptide subunits and the recognition of four anions to form a tetrahedral structure, in which the anions are located at the corners of the resulting structure. Each anion is coordinated to three different peptides. The structure was fully characterized by several techniques, including NMR spectroscopy and X-ray diffraction, and the material was able to facilitate the transmembrane transport of chloride ions.

Bioinspired Artificial Sodium and Potassium Ion Channels.

In Nature, all biological systems present a high level of compartmentalization in order to carry out a wide variety of functions in a very specific way. Hence, they need ways to be connected with the environment for communication, homeostasis equilibrium, nutrition, waste elimination, etc. The biological membranes carry out these functions; they consist of physical insulating barriers constituted mainly by phospholipids. These amphipathic molecules spontaneously aggregate in water to form bilayers in which the polar groups are exposed to the aqueous media while the non-polar chains self-organize by aggregating to each other to stay away from the aqueous media. The insulating properties of membranes are due to the formation of a hydrophobic bilayer covered at both sides by the hydrophilic phosphate groups. Thus, lipophilic molecules can permeate the membrane freely, while the small charged or very hydrophilic molecules require the assistance of other membrane components in order to overcome the energetic cost implied in crossing the non-polar region of the bilayer. Most of the large polar species (such as oligosaccharides, polypeptides or nucleic acids) cross into and out of the cell via endocytosis and exocytosis, respectively. Nature has created a series of systems (carriers and pores) in order to control the balance of small hydrophilic molecules and ions. The most important structures to achieve these goals are the ionophoric proteins that include the channel proteins, such as the sodium and potassium channels, and ionic transporters, including the sodium/potassium pumps or calcium/sodium exchangers among others. Inspired by these, scientists have created non-natural synthetic transporting structures to mimic the natural systems. The progress in the last years has been remarkable regarding the efficient transport of Na(+) and K(+) ions, despite the fact that the selectivity and the ON/OFF state of the non-natural systems remain a present and future challenge.

Self-assembling α,γ-cyclic peptides that generate cavities with tunable properties.

The design and synthesis of ß-sheet-based self-assembling cyclic peptides with tunable cavities is described. The incorporation of a γ-amino acid with a hydroxyl group at C2 allows the incorporation of different groups that modify the internal properties of the resulting dimeric ensemble. These dimers can entrap different guests depending on the properties of the group at C2. The guest defines the geometry of the resulting aggregate.