Impact effects of COVID-19 pandemic on chronic disease patients: A longitudinal prospective study.

AIMS: To assess the effects of COVID-19 pandemic on clinical variables as part of the routine clinical monitoring of patients with chronic diseases in primary care. DESIGN: A prospective longitudinal study was conducted in primary care centres of the Andalusian Health Service. METHODS: Data were recorded before the pandemic (T1), during the declaration of the state of emergency (T2) and in the transition phase (T3). The Barthel index and the Short Portable Mental Status Questionnaire (SPMSQ) were used to analyse functional and cognitive changes at the three time points. HbA1c, systolic and diastolic blood pressure, heart rate, BMI and lipid levels were assessed as clinical variables. Descriptive statistics and non-parametric chi-square test were used for analysis. STROBE checklist was used for the preparation of this paper. RESULTS: A total fo148 patients with chronic conditions were included in the analysis. Data analysis revealed in T2 only significant reductions in BMI, total levels of cholesterol and HDL during the onset of the pandemic. Barthel Index, SPMSQ, blood pressure and triglycerides and LDL levels worsened in T2, and the negative effects were maintained in T3. Compared to pre-pandemic values, HbA1c levels improved in T3, but HDL levels worsened. CONCLUSIONS: COVID-19 has drastically disrupted several functional, cognitive and biological variables. These results may be useful in identifying clinical parameters that deserve closer attention in the case of a new health crisis. Further studies are needed to assess the potential impacts of each specific chronic condition. IMPACT: Cognitive and functional status, blood pressure and triglycerides and LDL levels worsen in short term, maintaining the negative effects in medium-term.

Effects of active video games on physical function in independent community-dwelling older adults: A systematic review and meta-analysis.

AIM: To analyse the effects of active video games on physical function in independent community-dwelling older adults. DESIGN: Systematic review and meta-analysis of randomized controlled trials. DATA SOURCES: The CINAHL, LILACS, Medline, Proquest and Scopus databases were consulted, with no restriction by year of publication. REVIEW METHODS: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. The meta-analysis was performed using RevMan software. RESULTS: The analysis included 22 randomized controlled trials with a total of 1208 participants (all ≥55 years old). In our meta-analyses, the effects produced by playing the active video games (mean differences) were statistically significant for the variables Gait speed and Timed up-and-go. The differences between the control and experimental groups were not significant in the following tests: 6-minute walk, 30-second chair stand, balance (measured with the Berg Balance Scale), cadence, grip strength, knee extension strength, 8-Foot Up-and-Go or velocity. CONCLUSIONS: Physical exercise from participation in active video games has beneficial effects on two clinical parameters (Gait speed and Timed up-and-go) in independent community-dwelling older adults. However, the effects on other parameters do not differ from those obtained with conventional exercise training. Therefore, the clinical significance of these benefits is limited. IMPACT: Older adults usually perform little physical activity. In consequence, researchers have increasingly considered alternatives to traditional forms of exercise. One such is that provided by active video games, which can be a source of stimulation, encouraging adherence and motivation in exercise programmes. Our review shows that active video games can improve gait speed and mobility, but in other respects obtain no differences from conventional exercises. Further tailored randomized clinical trials should be undertaken with diverse populations of older adults to evaluate different physical function variables to determine the most appropriate training approach and its optimal design and duration.

Effect of a game-based intervention on preoperative pain and anxiety in children: A systematic review and meta-analysis.

BACKGROUND: Games are increasingly being used as a means of alleviating pain and anxiety in paediatric patients, in the view that this form of distraction is effective, non-invasive and non-pharmacological. AIMS: To determine whether a game-based intervention (via gamification or virtual reality) during the induction of anaesthesia reduces preoperative pain and anxiety in paediatric patients. METHODS: A systematic review with meta-analysis of randomised controlled trials was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and using RevMan software. The review was based on a search of the EMBASE, CINAHL, Medline, SciELO and Scopus databases, conducted in July 2021. No restriction was placed on the year of publication. RESULTS: 26 studies were found, with a total study population of 2525 children. Regarding pain reduction, no significant differences were reported. For anxiety during anaesthesia induction, however, a mean difference of -10.62 (95% CI -13.85, -7.39) on the Modified Yale Preoperative Anxiety Scale, in favour of game-based intervention, was recorded. CONCLUSIONS: Game-based interventions alleviate preoperative anxiety during the induction of anaesthesia in children. This innovative and pleasurable approach can be helpful in the care of paediatric surgical patients. RELEVANCE TO CLINICAL PRACTICE: In children, preoperative management is a challenging task for healthcare professionals, and game-based strategies could enhance results, improving patients' emotional health and boosting post-surgery recovery. Distractive games-based procedures should be considered for incorporation in the pre-surgery clinical workflow in order to optimise healthcare.

Influence of microphytobenthos on the sedimentary organic matter composition in two contrasting estuarine microhabitats.

The influence of microphytobenthic community on the composition of sedimentary organic matter was evaluated in two Bahía Blanca estuary microhabitats contrasting in vegetation and hydrodynamic conditions; namely, S1 located in a Sarcocornia perennis saltmarsh with macroscopic microbial mats and S2 in a mudflat without macroscopic microbial mats or vegetation. Moisture, organic matter, chlorophyll a, phaeopigments, carbohydrates (CH), proteins (PRT), and abundance and structure of microphytobenthic community were evaluated in surface sediments. Higher moisture was observed at S2 and was related to the proximity of this site to the subtidal zone and the effect of the environmental variables temperature and rain. No significant differences were found in organic matter content between sites; however, at S1, a higher concentration was registered during winter and early spring associated to the period of higher microphytobenthic biomass. Chlorophyll a and phaeopigments were higher at S1, attributed to the higher microphytobenthos abundance at this site. Differences in microphytobenthos were observed not only in quantity but also in community structure since at S1 filamentous cyanobacteria dominated the community, whereas at S2, higher abundance of centric diatoms and the absence of cyanobacteria were observed during most of the study. S1 showed higher concentration of proteins and carbohydrates which could be attributed to the higher production of fresh organic matter by microphytobenthos. The total protein and carbohydrate concentrations allowed us to classify both microhabitats into the meso-oligotrophic category, contrasting with the classification made by other authors using water column proxies.

Environmental and hydroclimatic factors influencing Vibrio populations in the estuarine zone of the Bengal delta.

The objective of this study was to determine environmental parameters driving Vibrio populations in the estuarine zone of the Bengal delta. Spatio-temporal data were collected at river estuary, mangrove, beach, pond, and canal sites. Effects of salinity, tidal amplitude, and a cyclone and tsunami were included in the study. Vibrio population shifts were found to be correlated with tide-driven salinity and suspended particulate matter (SPM). Increased abundance of Vibrio spp. in surface water was observed after a cyclone, attributed to re-suspension of benthic particulate organic carbon (POC), and increased availability of chitin and dissolved organic carbon (DOC). Approximately a two log10 increase in the (p < 0.05) number of Vibrio spp. was observed in < 20 µm particulates, compared with microphytoplankton (20-60 µm) and zooplankton > 60 µm fractions. Benthic and suspended sediment comprised a major reservoir of Vibrio spp. Results of microcosm experiments showed enhanced growth of vibrios was related to concentration of organic matter in SPM. It is concluded that SPM, POC, chitin, and salinity significantly influence abundance and distribution of vibrios in the Bengal delta estuarine zone.

Seasonal baseline of nutrients and stable isotopes in a saline lake of Argentina: biogeochemical processes and river runoff effects.

The seasonal variability of inorganic and organic nutrients and stable isotopes and their relations with plankton and environmental conditions were monitored in Lake Chasicó. Principal component analysis evidenced the strong influence of the river runoff on several biogeochemical variables. Silicate concentrations were controlled by diatom biomass and river discharge. Higher values of nitrate and soluble reactive phosphorus (SRP) indicated agricultural uses in the river basin. Elevated pH values (∼ 9) inhibiting nitrification in the lake explained partially the dominance of ammonium: ∼ 83 % of dissolved inorganic nitrogen (DIN). The low DIN/SRP ratio inferred nitrogen limitation, although the hypotheses of iron and CO2 limitation are relevant in alkaline lakes. Particulate organic matter (POM) and dissolved organic matter (DOM) were mainly of autochthonous origin. The main allochthonous input was imported by the river as POM owning to the arid conditions. Dissolved organic carbon was likely top-down regulated by the bacterioplankton grazer Brachionus plicatilis. The δ(13)C signature was a good indicator of primary production and its values were influenced probably by CO2 limitation. The δ(15)N did not evidence nitrogen fixation and suggested the effects of anthropogenic activities. The preservation of a good water quality in the lake is crucial for resource management.

Seasonal dynamics of Vibrio cholerae and its phages in riverine ecosystem of Gangetic West Bengal: cholera paradigm.

The Gangetic delta is a century-old cholera endemic belt where the role of riverine-estuarine ecosystem in cholera transmission has never been elucidated. Seasonality, distribution, and abundance of environmental Vibrio cholerae O1/O139 and vibriophage in Hooghly riverine-estuarine environment and their correlation with cholera incidence pattern in West Bengal, India, have been analyzed for the first time across summer, monsoon, and winter months. A total of 146 water samples collected from two sites of the Hooghly River (Howrah and Diamond Harbour) were analyzed physicochemically along with cultivable Vibrio count (CVC), V. cholerae O1/O139, and vibriophages. V. cholerae O1 was detected in 56 (38.3%) samples, while 66 (45.2%) were positive for V. cholerae O1 phages. Flood tide, water temperature (31 ± 1.6 °C), and turbidity (≥250 nephelometric turbidity unit (NTU)) significantly stimulated V. cholerae and vibriophage abundance in riverine ecosystem. Solitary existence of V. cholerae O1 and phages (p < 0.0001) in aquatic environment divulges the dominance of either of the entity (V. cholerae O1 or V. cholerae O1 Φ) on the other. Significant association (p < 0.05) between Kolkata cholera cases and V. cholerae O1 in aquatic environment implies the role of riverine-estuarine ecosystem in cholera transmission. A "biomonitoring tool" of physicochemical stimulants, tidal, and climatic variants has been proposed collating V. cholerae and phage dynamics that can forewarn any impending cholera outbreak.

Assessing the Risk of Hypertension in Chronic, Elderly Patients during the COVID-19 Pandemic: A Prospective Study.

BACKGROUND: This study considers care management for older chronic patients during and after the COVID-19 pandemic. AIMS: To identify groups of variables at previous time points as a basis for deriving efficient classification models during and after a pandemic situation and to quantify the effect of each variable within the model to predict levels of worsening risk in diastolic and systolic arterial hypertension (AHT). MATERIAL AND METHODS: In this prospective longitudinal study, data were collected at three time points: before, during, and after the COVID-19 pandemic period. RESULTS: The study included 148 patients with an average age of 81.6 years. During the study period, mean systolic blood pressure among this population rose by 5 mmHg to 128.8 mmHg; the number of patients with systolic blood pressure > 140 mmHg rose by 45.3%; among those with diastolic blood pressure > 90, the number rose by 41.2%; mean triglycerides levels rose to 152.6 mg/dL; cholesterol levels rose to 147 mg/dL; and LDL cholesterol rose to 112.2 mg/dL. Meanwhile, mean levels of HDL cholesterol decreased to 46.5 mg/dL. Binary-response logistic regression models were constructed to identify the most relevant variables for predicting AHT risk during and after the pandemic. The heart rate (OR = 1.79; 95% CI: 1.22-2.72) and body mass index (OR = 1.75; 95% CI: 1.08-2.94) variables were significant at the population level (p < 0.05) for diastolic and systolic AHT in the pandemic period risk models. The body mass index variable was also significant for diastolic AHT in the post-pandemic period risk model (OR = 1.97; 95% CI: 1.32-2.94), whilst the triglycerides variable was significant in the systolic AHT post-pandemic period risk model (OR = 1.49; 95% CI: 1.01-1.86). CONCLUSIONS: Bad control of arterial hypertension in older patients with chronic disease is associated with elevated levels of LDL cholesterol, total cholesterol, systolic blood pressure, heart rate and triglycerides, and lower levels of HDL cholesterol.

Towards the outwelling hypothesis in a Patagonian estuary: First support from lipid markers and bacterial communities.

Biogeochemical markers in combination with bacterial community composition were studied at two contrasting stations at the Río Negro (RN) estuary to assess the outwelling hypothesis in the Argentinian Patagonia. Inorganic nutrients and dissolved organic matter were exported clearly during the last hours of the ebb at the station Wetland. Moreover, a considerable outwelling of polyunsaturated fatty acids (PUFA), particulates and microalgae was inferred by this combined approach. The exported 22:6(n-3) and 20:5(n-3) contributed very likely to sustain higher trophic levels in the coasts of the Southwest Atlantic. The stable isotopes did not evidence clearly the outwelling; nevertheless, the combination of δ13C with fatty acid bacterial markers indicated organic matter degradation in the sediments. The dominance of Desulfobacterales and Desulfuromonadales suggested sulphate reduction in the sediments, a key mechanism for nutrient outwelling in salt marshes. Marivivens and other Rhodobacterales (Alphaproteobacteria) in the suspended particulate matter were clear indicators of the nutrient outwelling. The colonization of particles according to the island biogeography theory was a good hypothesis to explain the lower bacterial biodiversity at the wetland. The copiotrophic conditions of the RN estuary and particularly at the wetland were deduced also by the dynamic of some Actinobacteria, Bacteroidia and Gammaproteobacteria. This high-resolution snapshot combining isotopic, lipid and bacterial markers offers key pioneer insights into biogeochemical and ecological processes of the RN estuary.

Poor Cognitive Agility Conservation in Obese Aging People.

Life expectancy has been boosted in recent decades at expenses of increasing the age-associated diseases. Dementia, for its incidence, stands out among the pathologies associated with aging. The exacerbated cognitive deterioration disables people from carrying out their daily lives autonomously and this incidence increases exponentially after 65 years of age. The etiology of dementia is a miscellaneous combination of risk factors that restrain the quality of life of our elderly. In this sense, it has been established that some metabolic pathologies such as obesity and diabetes act as a risk factor for dementia development. In contrast, a high educational level, as well as moderate physical activity, have been shown to be protective factors against cognitive impairment and the development of dementia. In the present study, we have evaluated the metabolic composition of a population between 60-90 years old, mentally healthy and with high academic degrees. After assessing agility in mental state, we have established relationships between their cognitive abilities and their body composition. Our data support that excess body fat is associated with poorer maintenance of cognition, while higher percentages of muscle mass are associated with the best results in the cognitive tests.

Anxiety, Distress and Stress among Patients with Diabetes during COVID-19 Pandemic: A Systematic Review and Meta-Analysis.

The prevalence of mental health disorders has increased during the COVID-19 pandemic. Patients with chronic diseases, such as diabetes, are a particularly vulnerable risk group. This study aims to assess the levels and prevalence of anxiety, distress, and stress in patients with diabetes during the COVID-19 pandemic. A systematic review was conducted in CINAHL, Cochrane, LILACS, Medline, SciELO, and Scopus in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Thirty-seven articles with a total of 13,932 diabetic patients were included. Five meta-analyses were performed. The prevalence of anxiety was 23% (95% CI = 19-28) in T1DM and 20% (95% CI = 6-40) in T2DM patients. For diabetes distress it was 41% (95% CI = 24-60) for T1DM and 36% in T2DM patients (95% CI = 2-84). For stress, the prevalence was 79% (95% CI = 49-98) in T1DM patients. People with diabetes have significant psychiatric comorbidity as well as psychological factors that negatively affect disease management, increasing their vulnerability in an emergency situation. To establish comprehensive care in diabetic patients addressing mental health is essential, as well as including specific policy interventions to reduce the potential psychological harm of the COVID-19 pandemic.

Prevalence of Depression and Related Factors among Patients with Chronic Disease during the COVID-19 Pandemic: A Systematic Review and Meta-Analysis.

The management of chronic diseases in the midst of the COVID-19 pandemic is especially challenging, and reducing potential psychological harm is essential. This review aims to determine the prevalence of depression during the COVID-19 pandemic in patients with chronic disease, and to characterize the impacts of related factors. A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The meta-analysis was performed using StatsDirect software. The review identified 33 articles with a total of 50,905 patients with chronic diseases. Four meta-analyses were performed to estimate the prevalence of depression. In diabetic patients, the prevalence ranged from 17% (95% CI = 7-31) (PHQ-9) to 33% (95% CI = 16-51) (PHQ-8); in obese patients, the prevalence was 48% (95% CI = 26-71); and in hypertensive patients, the prevalence was 18% (95% CI = 13-24). The factors significantly associated with depression were female sex, being single, deterioration in the clinical parameters of diabetes, a decrease in self-care behavior, reduced physical activity and sleep time and fear of contagion. The COVID-19 pandemic has significantly increased levels of depression among persons with chronic disease. Pandemics and other emergency events have a major impact on mental health, so early psychological interventions and health management policies are needed to reinforce chronic patients' physical and mental health.

Prevalence, O-genotype and Shiga toxin (Stx) 2 subtype of Stx-producing Escherichia coli strains isolated from Argentinean beef cattle.

The aims of this study were to investigate prevalence, O-genotype, and virulence gene profile including Shiga toxin (Stx) 2 gene-subtype of Stx-producing Escherichia coli (STEC) in beef cattle from the Bahía Blanca in Argentina. Rectal swabs were collected from 283 beef cattle in 2012. stx genes were detected in 90 (32%) out of the 283 rectal swabs by stx gene-specific PCR assay. The positive cases were 13 with stx1, 58 with stx2, and 19 with both stx1 and stx2. Among 90 stx gene-positive samples, 45 STEC strains were isolated, which included 3 stx1, 34 stx2, and eight stx1 and stx2 genes positive isolates. O-genotyping grouped 45 STEC strains into 19 different O-genotypes such as Og8, Og145, Og171, Og185 (4 from each), Og22, Og153, Og157 (3 from each) and others. Various stx2 gene-subtypes were identified in 42 STEC strains: 13 positive cases for stx2a, 11 for stx2c, 3 for stx2g, 10 for stx2a and stx2d, 4 for stx2a and stx2c, and 1 for stx2b, stx2c and stx2g. efaI gene, generally prevalent in clinical strains, was detected in relatively high in the STEC strains. These data suggest that stx2a and stx2c were distributed not only in O145 and O157 but also in minor O-genotypes of STEC in Argentina.

Chemically unidentified dissolved organic carbon: A pivotal piece for microbial activity in a productive area of the Northern Patagonian shelf.

The biochemical composition and fluorescence properties of DOM were assessed in relation to phytoplankton and major aquatic bacterial clades in a regenerative area of the Argentine Shelf. DOM was mainly of autochthonous biological origin, containing humic- and protein-like substances of medium degree of unsaturation and diagenesis. Biochemical-DOM accounted for 25% of total DOC, being dissolved combined amino acids (DCAA) the dominant fraction followed by free carbohydrates. Phytoplankton was the main source of serine, alanine, and valine, and particulate carbohydrates. Gammaproteobacteria abundance correlated negatively with ammonium and positively with DCAA, suggesting a coupling between ammonium consumption and refractory amino acid production. A preferential utilization of alanine, leucine and threonine as nitrogen source was inferred from the distribution of Cytophaga-Flavobacteria-Bacteroidete in relation with dissolved free amino acids (DFAA). Notably, Alpha- and Betaproteobacteria correlated with the large pool (75%) of chemically unidentified DOC and not with DCAA or dissolved combined carbohydrates. Particularly, Alphaproteobacteria (∼40% of EUB total heterotrophic bacteria) either significantly contribute to the production of the "humic", refractory fraction of marine DOM, or the latter impairs resource control on their abundance. Spatial heterogeneity inherent to coastal-shelf areas drives important regional variability in the biochemical properties of DOM.

Gamification for the Improvement of Diet, Nutritional Habits, and Body Composition in Children and Adolescents: A Systematic Review and Meta-Analysis.

Currently, one of the main public health problems among children and adolescents is poor adherence to healthy habits, leading to increasingly high rates of obesity and the comorbidities that accompany obesity. Early interventions are necessary, and among them, the use of gamification can be an effective method. The objective was to analyse the effect of game-based interventions (gamification) for improving nutritional habits, knowledge, and changes in body composition. A systematic review and meta-analysis were performed in CINAHL, EMBASE, LILACS, MEDLINE, SciELO, and Scopus databases, following the PRISMA recommendations. There was no restriction by year of publication or language. Only randomized controlled trials were included. Twenty-three articles were found. After the intervention, the consumption of fruit and vegetables increased, as well as the knowledge on healthy food groups. The means difference showed a higher nutritional knowledge score in the intervention group 95% CI 0.88 (0.05-1.75). No significant effect of gamification was found for body mass index z-score. Gamification could be an effective method to improve nutritional knowledge about healthier nutritional habits. Promoting the development of effective educational tools to support learning related to nutrition is necessary in order to avoid and prevent chronic diseases.

Vibrio and Bacterial Communities Across a Pollution Gradient in the Bay of Bengal: Unraveling Their Biogeochemical Drivers.

The highly populated coasts of the Bay of Bengal are particularly vulnerable to water-borne diseases, pollution and climatic extremes. The environmental factors behind bacterial community composition and Vibrio distribution were investigated in an estuarine system of a cholera-endemic region in the coastline of Bangladesh. Higher temperatures and sewage pollution were important drivers of the abundance of toxigenic Vibrio cholerae. A closer relation between non-culturable Vibrio and particulate organic matter (POM) was inferred during the post-monsoon. The distribution of operational taxonomic units (OTUs) of Vibrio genus was likely driven by salinity and temperature. The resuspension of sediments increased Vibrio abundance and organic nutrient concentrations. The δ13C dynamic in POM followed an increasing gradient from freshwater to marine stations; nevertheless, it was not a marker of sewage pollution. Bacteroidales and culturable coliforms were reliable indicators of untreated wastewater during pre and post-monsoon seasons. The presumptive incorporation of depleted-ammonium derived from ammonification processes under the hypoxic conditions, by some microorganisms such as Cloacibacterium and particularly by Arcobacter nearby the sewage discharge, contributed to the drastic 15N depletion in the POM. The likely capacity of extracellular polymeric substances production of these taxa may facilitate the colonization of POM from anthropogenic origin and may signify important properties for wastewater bioremediation. Genera of potential pathogens other than Vibrio associated with sewage pollution were Acinetobacter, Aeromonas, Arcobacter, and Bergeyella. The changing environmental conditions of the estuary favored the abundance of early colonizers and the island biogeography theory explained the distribution of some bacterial groups. This multidisciplinary study evidenced clearly the eutrophic conditions of the Karnaphuli estuary and assessed comprehensively its current bacterial baseline and potential risks. The prevailing conditions together with human overpopulation and frequent natural disasters, transform the region in one of the most vulnerable to climate change. Adaptive management strategies are urgently needed to enhance ecosystem health.

A protocol for the simultaneous identification of chitin-containing particles and their associated bacteria.

Chitin is the second most abundant polymer on Earth, playing a crucial role in the biogeochemical cycles. A core issue for studying its processing in aquatic systems is the identification and enumeration of chitin-containing particles and organisms, ideally in a manner that can be directly linked to bulk chitin quantification. The aim of this study was the development of such a technique. We successfully combined the methodology of bulk chitin determination using wheat germ agglutinin (FITC-WGA) for staining chitin-containing particles and organisms along with CARD-FISH staining of either chitin-containing eukaryotic cells or bacteria associated with them. Environmental chitin staining was successfully applied to natural water samples. Fungal hyphae, diatoms, and dinoflagellates, sestonic aggregates and chitin-containing structures derived from metazoa were observed. Also, hybridized bacteria attached to chitinaceous debris were clearly visualized. Finally, as proof of principle, cultured yeast cells were simultaneously-targeted by FITC-WGA and the EUK516 probe without exhibiting any interference between both stains. The presented approach appears as a powerful tool to evaluate the contribution of different size classes and organisms to chitin production and consumption, opening the possibility for application of single-cell approaches targeting the ecophysiology of chitin transformations in aquatic systems.

Biogeochemical and hydrological drivers of the dynamics of Vibrio species in two Patagonian estuaries.

The ecology of the most relevant Vibrio species for human health and their relation to water quality and biogeochemistry were studied in two estuaries in Argentinian Patagonia. Vibrio cholerae and Vibrio parahaemolyticus were reported in >29% of cases at the Río Colorado and Río Negro estuaries. Neither the pandemic serogroups of Vibrio cholerae O1, Vibrio cholerae O139 nor the cholera toxin gene were detected in this study. However, several strains of V. cholerae (not O1 or O139) are able to cause human disease or acquire pathogenic genes by horizontal transfer. Vibrio vulnificus was detected only in three instances in the microplankton fraction of the Río Negro estuary. The higher salinity in the Río Colorado estuary and in marine stations at both estuaries favours an abundance of culturable Vibrio. The extreme peaks for ammonium, heterotrophic bacteria and faecal coliforms in the Río Negro estuary supported a marked impact on sewage discharge. Generally, the more pathogenic strains of Vibrio have a faecal origin. Salinity, pH, ammonium, chlorophyll a, silicate and carbon/nitrogen ratio of suspended organic particulates were the primary factors explaining the distribution of culturable bacteria after distance-based linear models. Several effects of dissolved organic carbon on bacterial distribution are inferred. Global change is expected to increase the trophic state and the salinisation of Patagonian estuaries. Consequently, the distribution and abundance of Vibrio species is projected to increase under future changing baselines. Adaptation strategies should contribute to sustaining good water quality to buffer climate- and anthropogenic- driven impacts.

Azadinium poporum from the Argentine Continental Shelf, Southwestern Atlantic, produces azaspiracid-2 and azaspiracid-2 phosphate.

The marine dinophycean genus Azadinium has been identified as the primary source of azaspiracids (AZA), a group of lipophilic phycotoxins known to accumulate in shellfish. Blooms of Azadinium in the southern Atlantic off Argentina have been described from the 1990s, but due to a lack of cultures, the diversity of South-Atlantic Azadinium has not yet been fully explored and their toxin production potential is completely unknown. During a spring 2010 research cruise covering the El Rincón (ER) estuarine system (North Patagonian coast, Argentina, Southwestern Atlantic) a search was conducted for the presence of Azadinium. Although neither Azadinium cells nor AZA in field plankton samples were detected, 10 clonal strains of Azadinium poporum were successfuly established by incubation of sediment samples. Argentinean A. poporum were more variable in size and shape than the type description but conformed to it by the presence of multiple pyrenoids with starch sheath, in plate pattern and arrangement, and in the position of the ventral pore located on the left side of the pore plate. In contrast to all previous description of A. poporum, isolates of the Argentinean A. poporum possessed a distinct field of pores on the second antapical plate. Conspecificity of the Argentinean isolates with A. poporum was confirmed by molecular phylogeny of concatenated ITS and LSU rDNA sequences, where all Argentinean isolates together with some Chinese A. poporum strains formed a well-supported ribotype clade within A. poporum. All isolates produced AZA with the same profile, consisting of AZA-2 as the major compound and, to a lesser extent, its phosphated form. This is the first report of a phosphated marine algal toxin. This first confirmation of the presence of AZA producing Azadinium in the Argentinean coastal area underlines the risk of AZA shellfish contamination episodes in the Southwestern Atlantic region.

Global change effects on biogeochemical processes of Argentinian estuaries: an overview of vulnerabilities and ecohydrological adaptive outlooks.

The aims of this work are to provide an overview of the current stresses of estuaries in Argentina and to propose adaptation strategies from an ecohydrological approach. Several Argentinian estuaries are impacted by pollutants, derived mainly from sewage discharge and agricultural or industrial activities. Anthropogenic impacts are expected to rise with increasing human population. Climate-driven warmer temperature and hydrological changes will alter stratification, residence time, oxygen content, salinity, pollutant distribution, organism physiology and ecology, and nutrient dynamics. Good water quality is essential in enhancing estuarine ecological resilience to disturbances brought on by global change. The preservation, restoration, and creation of wetlands will help to protect the coast from erosion, increase sediment accretion rates, and improve water quality by removing excess nutrients and pollutants. The capacity of hydrologic basin ecosystems to absorb human and natural impacts can be improved through holistic management, which should consider social vulnerability in complex human-natural systems.