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1.
Eur Phys J C Part Fields ; 84(5): 553, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827813

RESUMO

Motivated by the recent evidence for B+→K+ν¯ν decays at Belle II, we point out that fully invisible Bd and Bs meson decays are strongly constrained by LEP. A reinterpretation of an old inclusive ALEPH search for b-hadron decays with large missing energy allows us to place the limits Br(Bd→invisible)<1.4×10-4 and Br(Bs→invisible)<5.6×10-4, both at 90% CL. The Bd limit is only a factor of 6 looser than the world-leading one provided by the BaBar collaboration, while the Bs one is the first limit in the literature on this decay mode. These results are relevant in the context of new light states coupled to quarks and exemplify the power of a future Tera-Z factory at FCC-ee to look for B meson decays containing missing energy.

2.
Harmful Algae ; 135: 102649, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38830714

RESUMO

Protoceratium reticulatum is the main yessotoxin-producer along the Chilean coast. Thus far, the yessotoxin levels recorded in this region have not posed a serious threat to human health. However, a bloom of P. reticulatum during the austral summer of 2022 caused the first ban of shellfish collection, due to the high toxin levels. A bloom of P. reticulatum during the austral summer of 2020 allowed an evaluation of the fine-scale distribution of the dinoflagellate during a tidal cycle. High-resolution measurements of biophysical properties were carried out in mid-summer (February 18-19) at a fixed sampling station in Puyuhuapi Fjord, Chilean Patagonia, as part of an intensive 24-h biophysical experiment to monitor the circadian distributions of P. reticulatum vegetative cells and yessotoxins. High P. reticulatum cell densities (>20 × 103 cells L-1) were found in association with a warmer (14.5-15 °C) and estuarine (23.5-24.5 g kg-1) sub-surface water layer (6-8 m). P. reticulatum cell numbers and yessotoxins followed a synchronic distribution pattern consistent with the excursions of the pycnocline. Nevertheless, the surface aggregation of the cells was modulated by the light cycle, suggesting daily vertical migration. The yessotoxin content per P. reticulatum cell ranged from 9.4 to 52.2 pg. This study demonstrates both the value of fine-scale resolution measurements of biophysical properties in a highly stratified system and the potential ecosystem impact of P. reticulatum strains producing high levels of yessotoxins.


Assuntos
Dinoflagellida , Venenos de Moluscos , Oxocinas , Dinoflagellida/fisiologia , Oxocinas/análise , Chile , Estuários , Luz , Proliferação Nociva de Algas , Toxinas Marinhas/análise
3.
N Engl J Med ; 390(22): 2061-2073, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38767248

RESUMO

BACKGROUND: Many persons with chronic obstructive pulmonary disease (COPD) or asthma have not received a diagnosis, so their respiratory symptoms remain largely untreated. METHODS: We used a case-finding method to identify adults in the community with respiratory symptoms without diagnosed lung disease. Participants who were found to have undiagnosed COPD or asthma on spirometry were enrolled in a multicenter, randomized, controlled trial to determine whether early diagnosis and treatment reduces health care utilization for respiratory illness and improves health outcomes. Participants were assigned to receive the intervention (evaluation by a pulmonologist and an asthma-COPD educator who were instructed to initiate guideline-based care) or usual care by their primary care practitioner. The primary outcome was the annualized rate of participant-initiated health care utilization for respiratory illness. Secondary outcomes included changes from baseline to 1 year in disease-specific quality of life, as assessed with the St. George Respiratory Questionnaire (SGRQ; scores range from 0 to 100, with lower scores indicating better health status); symptom burden, as assessed with the COPD Assessment Test (CAT; scores range from 0 to 40, with lower scores indicating better health status); and forced expiratory volume in 1 second (FEV1). RESULTS: Of 38,353 persons interviewed, 595 were found to have undiagnosed COPD or asthma and 508 underwent randomization: 253 were assigned to the intervention group and 255 to the usual-care group. The annualized rate of a primary-outcome event was lower in the intervention group than in the usual-care group (0.53 vs. 1.12 events per person-year; incidence rate ratio, 0.48; 95% confidence interval [CI], 0.36 to 0.63; P<0.001). At 12 months, the SGRQ score was lower than the baseline score by 10.2 points in the intervention group and by 6.8 points in the usual-care group (difference, -3.5 points; 95% CI, -6.0 to -0.9), and the CAT score was lower than the baseline score by 3.8 points and 2.6 points, respectively (difference, -1.3 points; 95% CI, -2.4 to -0.1). The FEV1 increased by 119 ml in the intervention group and by 22 ml in the usual-care group (difference, 94 ml; 95% CI, 50 to 138). The incidence of adverse events was similar in the trial groups. CONCLUSIONS: In this trial in which a strategy was used to identify adults in the community with undiagnosed asthma or COPD, those who received pulmonologist-directed treatment had less subsequent health care utilization for respiratory illness than those who received usual care. (Funded by Canadian Institutes of Health Research; UCAP ClinicalTrials.gov number, NCT03148210.).


Assuntos
Asma , Diagnóstico Precoce , Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Asma/diagnóstico , Asma/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Espirometria , Volume Expiratório Forçado , Adulto
4.
Sports Med Health Sci ; 6(2): 101-110, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38708322

RESUMO

Proprioception is significantly impaired in knee osteoarthritis (KOA), contributing to reduced functionality. Strength training (ST) is essential in KOA by improving muscle strength, although it may also be effective in improving proprioception. The purpose was to determine the effect of ST on knee proprioception in KOA patients. Pubmed, CINAHL, Scopus, WOS, and PEDro were searched for randomized controlled trials (RCTs) (inception to March 2023). Comparisons for ST were physical exercise different from ST, non-exercise-based interventions, and no intervention. Methodological quality was assessed using the PEDro scale, and risk of bias (RoB) using the Cochrane tool. Meta-analyses were performed by comparison groups using the standardized mean difference (SMD) (Hedge's g) with random effects models, also considering subgroups by proprioception tests. Finally, six RCTs were included. The mean PEDro score was 6.3, and the highest proportion of biases corresponds to performance, selection, and detection. The meta-analysis indicated that only when compared with non-intervention, ST significantly improved knee proprioception for the joint position sense (JPS) (active + passive), JPS (passive), and threshold to detect passive motion (TTDPM) subgroups (g â€‹= â€‹-1.33 [-2.33, -0.32], g = â€‹-2.29 [-2.82, -1.75] and g â€‹= â€‹-2.40 [-4.23, -0.58], respectively). However, in the knee JPS (active) subgroup, ST was not significant (g â€‹= â€‹-0.72 [-1.84, 0.40]). In conclusion, ST improves knee proprioception compared to non-intervention. However, due to the paucity of studies and diversity of interventions, more evidence is needed to support the effectiveness of ST. Future RCTs may address the limitations of this review to advance knowledge about proprioceptive responses to ST and contribute to clinical practice.

5.
Lancet Respir Med ; 12(7): 556-574, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38677306

RESUMO

Indigenous peoples around the world bear a disproportionate burden of chronic respiratory diseases, which are associated with increased risks of morbidity and mortality. Despite the imperative to address global inequity, research focused on strengthening respiratory health in Indigenous peoples is lacking, particularly in low-income and middle-income countries. Drivers of the increased rates and severity of chronic respiratory diseases in Indigenous peoples include a high prevalence of risk factors (eg, prematurity, low birthweight, poor nutrition, air pollution, high burden of infections, and poverty) and poor access to appropriate diagnosis and care, which might be linked to colonisation and historical and current systemic racism. Efforts to tackle this disproportionate burden of chronic respiratory diseases must include both global approaches to address contributing factors, including decolonisation of health care and research, and local approaches, co-designed with Indigenous people, to ensure the provision of culturally strengthened care with more equitable prioritisation of resources. Here, we review evidence on the burden of chronic respiratory diseases in Indigenous peoples globally, summarise factors that underlie health disparities between Indigenous and non-Indigenous people, propose a framework of approaches to improve the respiratory health of Indigenous peoples, and outline future directions for clinical care and research.


Assuntos
Povos Indígenas , Humanos , Doença Crônica/terapia , Doença Crônica/etnologia , Saúde Global , Disparidades em Assistência à Saúde/etnologia , Doenças Respiratórias/terapia , Doenças Respiratórias/etnologia , Doenças Respiratórias/epidemiologia , Serviços de Saúde do Indígena/organização & administração , Disparidades nos Níveis de Saúde , Fatores de Risco , Desigualdades de Saúde
6.
Toxins (Basel) ; 16(2)2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393154

RESUMO

At the end of summer 2020, a moderate (~105 cells L-1) bloom of potential fish-killing Karenia spp. was detected in samples from a 24 h study focused on Dinophysis spp. in the outer reaches of the Pitipalena-Añihue Marine Protected Area. Previous Karenia events with devastating effects on caged salmon and the wild fauna of Chilean Patagonia had been restricted to offshore waters, eventually reaching the southern coasts of Chiloé Island through the channel connecting the Chiloé Inland Sea to the Pacific Ocean. This event occurred at the onset of the COVID-19 lockdown when monitoring activities were slackened. A few salmon mortalities were related to other fish-killing species (e.g., Margalefidinium polykrikoides). As in the major Karenia event in 1999, the austral summer of 2020 was characterised by negative anomalies in rainfall and river outflow and a severe drought in March. Karenia spp. appeared to have been advected in a warm (14-15 °C) surface layer of estuarine saline water (S > 21). A lack of daily vertical migration patterns and cells dispersed through the whole water column suggested a declining population. Satellite images confirmed the decline, but gave evidence of dynamic multifrontal patterns of temperature and chl a distribution. A conceptual circulation model is proposed to explain the hypothetical retention of the Karenia bloom by a coastally generated eddy coupled with the semidiurnal tides at the mouth of Pitipalena Fjord. Thermal fronts generated by (topographically induced) upwelling around the Tic Toc Seamount are proposed as hot spots for the accumulation of swimming dinoflagellates in summer in the southern Chiloé Inland Sea. The results here provide helpful information on the environmental conditions and water column structure favouring Karenia occurrence. Thermohaline properties in the surface layer in summer can be used to develop a risk index (positive if the EFW layer is thin or absent).


Assuntos
Dinoflagellida , Animais , Estuários , Chile , Ecossistema , Oceanos e Mares , Peixes , Salmão , Proliferação Nociva de Algas
7.
Harmful Algae ; 132: 102583, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38331541

RESUMO

The bays of Tongoy and Guanaqueros are located in the Humboldt Current system, where Argopecten purpuratus has been the subject of intense aquaculture development. These bays lie in one of the most productive marine ecosystems on Earth and are dominated by permanent coastal upwelling at Lengua de Vaca Point and Choros Point, one of the three upwelling centers on the Chilean coast. Significantly, this productive system experiences a high recurrence of harmful algal bloom (HAB) events. This paper examines 9-year (2010-2018) samples of three toxic microalgal species collected in different monitoring programs and research projects. During this period, nine HAB events were detected in Guanaqueros Bay and 14 in Tongoy Bay. Among these, three HAB events were produced simultaneously in both bays by Pseudo-nitzschia australis, and two events produced simultaneously were detected in one bay by Alexandrium spp. and the other by Dinophysis acuminata. Before El Niño 2015-16, there were more HAB events of longer duration by the three species. Since El Niño, the number and duration of events were reduced and only produced by P. australis. HAB events were simulated with the FVCOM model and a virtual particle tracker model to evaluate the dynamics of bays and their relationship with HAB events. The results showed retention in bays during the relaxation conditions of upwelling and low connectivity between bays, which explains why almost no simultaneous events were recorded.


Assuntos
Dinoflagellida , Proliferação Nociva de Algas , Baías , Ecossistema , Chile
8.
Mar Pollut Bull ; 199: 116022, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211543

RESUMO

The effects of yessotoxins (YTXs) produced by the dinoflagellate Protoceratium reticulatum in the early stages of bivalves have not been studied in detail. The present study evaluates the effects of P. reticulatum and YTXs on the survival and feed ingestion of veliger larvae of Argopecten purpuratus. Larvae were 96 h-exposed to 500, 1000 and 2000 P. reticulatum cells mL-1, and their equivalent YTX extract was prepared in methanol. Results show a survival mean of 82 % at the highest density of dinoflagellate, and 38 % for larvae with the highest amount of YTX extract. Feed ingestion is reduced in the dinoflagellate exposure treatments as a function of cell density. Therefore, the effect of YTXs on A. purpuratus represents a new and important area of study for investigations into the deleterious effects of these toxins in the early stages of the life cycle of this and, potentially, other bivalves.


Assuntos
Bivalves , Dinoflagellida , Venenos de Moluscos , Oxocinas , Pectinidae , Animais , Toxinas Marinhas/metabolismo , Larva , Dinoflagellida/metabolismo , Ingestão de Alimentos
9.
BMC Pulm Med ; 23(1): 496, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071285

RESUMO

BACKGROUND: Some patients with asthma demonstrate normal spirometry and remain undiagnosed without further testing. OBJECTIVE: To determine clinical predictors of asthma in symptomatic adults with normal spirometry, and to generate a tool to help clinicians decide who should undergo bronchial challenge testing (BCT). METHODS: Using random-digit dialling and population-based case-finding, we recruited adults from the community with respiratory symptoms and no previous history of diagnosed lung disease. Participants with normal pre- and post-bronchodilator spirometry subsequently underwent BCT. Asthma was diagnosed in those with symptoms and a methacholine provocative concentration (PC20) of < 8 mg/ml. Sputum and blood eosinophils, and exhaled nitric oxide were measured. Univariate analyses identified potentially predictive variables, which were then used to construct a multivariable logistic regression model to predict asthma. Model sensitivity, specificity, and area under the receiver operating curve (AUC) were calculated. RESULTS: Of 132 symptomatic individuals with normal spirometry, 34 (26%) had asthma. Of those ultimately diagnosed with asthma, 33 (97%) answered 'yes' to a question asking whether they experienced cough, chest tightness or wheezing provoked by exercise or cold air. Other univariate predictors of asthma included female sex, pre-bronchodilator FEV1 percentage predicted, and percent positive change in FEV1 post bronchodilator. A multivariable model containing these predictive variables yielded an AUC of 0.82 (95% CI: 0.72-0.91), a sensitivity of 82%, and a specificity of 66%. The model was used to construct a nomogram to advise clinicians which patients should be prioritized for BCT. CONCLUSIONS: Four readily available patient characteristics demonstrated a high sensitivity and AUC for predicting undiagnosed asthma in symptomatic adults with normal pre- and post-bronchodilator spirometry. These characteristics can potentially help clinicians to decide which individuals with normal spirometry should be investigated with bronchial challenge testing. However, further prospective validation of our decision tool is required.


Assuntos
Asma , Broncodilatadores , Adulto , Feminino , Humanos , Asma/diagnóstico , Brônquios , Testes de Provocação Brônquica , Volume Expiratório Forçado , Cloreto de Metacolina , Espirometria
10.
Harmful Algae ; 130: 102520, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38061816

RESUMO

To expand knowledge of Pseudo-nitzschia species in the Southeast Pacific, we isolated specimens from coastal waters of central Chile (36°S-30°S), the Gulf of Corcovado, and the oceanic Robinson Crusoe Island (700 km offshore) and grew them into monoclonal strains. A total of 123 Pseudo-nitzschia strains were identified to 11 species based on sequencing of the ITS region of the nuclear rDNA and on ultrastructural and morphometric analyses of the frustule in selected representatives of each clade: P. australis, P. bucculenta, P. cf. chiniana, P. cf. decipiens, P. fraudulenta, P. hasleana, P. multistriata, P. plurisecta, P. cf. sabit, the new species P. dampieri sp. nov., and one undescribed species. Partial 18S and 28S rDNA sequences, including the hypervariable V4 and D1-D3 regions used for barcoding, were gathered from representative strains of each species to facilitate future metabarcoding studies. Results showed different levels of genetic, and at times ultrastructural, diversity among the above-mentioned entities, suggesting morphological variants (P. bucculenta), rapidly radiating complexes with ill-defined species boundaries (P. cf. decipiens and P. cf. sabit), and the presence of new species (P. dampieri sp. nov., Pseudo-nitzschia sp. 1, and probably P. cf. chiniana). Domoic acid (DA) was detected in 18 out of 82 strains tested, including those of P. australis, P. plurisecta, and P. multistriata. Toxicity varied among species mostly corresponding to expectations from previous reports, with the prominent exception of P. fraudulenta; DA was not detected in any of its 10 strains tested. In conclusion, a high diversity of Pseudo-nitzschia exists in Chilean waters, particularly offshore.


Assuntos
Diatomáceas , Diatomáceas/química , Plâncton , Oceanos e Mares , DNA Ribossômico , Chile
11.
Harmful Algae ; 129: 102495, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37951626

RESUMO

The frequency of harmful algal blooms (HABs) has increased over the last two decades, a phenomenon enhanced by global climate change. However, the effects of climate change will not be distributed equally, and Chile has emerged as one important, vulnerable area. The Chilean Patagonian region (41‒56°S) hosts two marine ecoregions that support robust blue economies via wild fisheries, aquaculture, and tourism. However, the harmful algal bloom-forming dinoflagellate Alexandrium catenella, a causative agent of paralytic shellfish poisoning outbreaks, threatens the viability of blue industries in this region and others worldwide. Despite the proliferation of A. catenella blooms over the last few decades, the role of sedimentary resting cysts in the recurrence of harmful algal blooms and the species' northward expansion across Chilean Patagonia is not well understood. As a resting cyst-producing species, the sediment-cyst dynamics of A. catenella likely contribute to the geographical expansion and bloom recurrence of this species. For this purpose, we analyzed a decade of A. catenella surface sediment cyst records across the two ecoregions of the Chilean Patagonian System that were further stratified into five subregions based on water temperature, salinity, dissolved oxygen, and nutrient characteristics. We also analyzed spatio-temporal cyst dynamics in a pre-, during-, and post-bloom scenario of the Chiloense ecoregion (more northern) of the Magellanic province. Our results indicated highly variable A. catenella resting cyst abundances, with a maximum of 221 cysts cm-3 recorded in 2002 after an intense bloom. Generalized linear mixed models and linear mixed models found that sampling season, subregion, and Total Organic Matter (%) explained resting cyst presence and density. The results also demonstrated the presence of A. catenella cysts in northern subregions, evidencing the northward geographical expansion observed during the last few decades. The risks of A. catenella bloom recurrence from small, patchy resting cyst distributions across broad geographical areas and under changing environmental conditions are discussed.


Assuntos
Dinoflagellida , Intoxicação por Frutos do Mar , Proliferação Nociva de Algas , Temperatura , Aquicultura
12.
Am J Respir Crit Care Med ; 208(12): 1271-1282, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37792953

RESUMO

Rationale: A significant proportion of individuals with chronic obstructive pulmonary disease (COPD) and asthma remain undiagnosed. Objectives: The objective of this study was to evaluate symptoms, quality of life, healthcare use, and work productivity in subjects with undiagnosed COPD or asthma compared with those previously diagnosed, as well as healthy control subjects. Methods: This multicenter population-based case-finding study randomly recruited adults with respiratory symptoms who had no previous history of diagnosed lung disease from 17 Canadian centers using random digit dialing. Participants who exceeded symptom thresholds on the Asthma Screening Questionnaire or the COPD Diagnostic Questionnaire underwent pre- and post-bronchodilator spirometry to determine if they met diagnostic criteria for COPD or asthma. Two control groups, a healthy group without respiratory symptoms and a symptomatic group with previously diagnosed COPD or asthma, were similarly recruited. Measurements and Main Results: A total of 26,905 symptomatic individuals were interviewed, and 4,272 subjects were eligible. Of these, 2,857 completed pre- and post-bronchodilator spirometry, and 595 (21%) met diagnostic criteria for COPD or asthma. Individuals with undiagnosed COPD or asthma reported greater impact of symptoms on health status and daily activities, worse disease-specific and general quality of life, greater healthcare use, and poorer work productivity than healthy control subjects. Individuals with undiagnosed asthma had symptoms, quality of life, and healthcare use burden similar to those of individuals with previously diagnosed asthma, whereas subjects with undiagnosed COPD were less disabled than those with previously diagnosed COPD. Conclusions: Undiagnosed COPD or asthma imposes important, unmeasured burdens on the healthcare system and is associated with poor health status and negative effects on work productivity.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Adulto , Humanos , Qualidade de Vida , Broncodilatadores , Fatores de Risco , Canadá/epidemiologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Asma/diagnóstico , Asma/epidemiologia , Espirometria , Atenção à Saúde , Volume Expiratório Forçado
13.
J Clin Med ; 12(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37892618

RESUMO

BACKGROUND: Back pain is highly prevalent; in Spain, it produces a very high economic cost and the scientific evidence supporting treatments shows low to moderate evidence for exercise. Therefore, the aim of this study was to assess the effectiveness of a therapeutic group exercise protocol in reducing pain intensity and disability in patients with back pain in primary health care setting. METHODS: A total sample of 149 patients who suffered from chronic non-specific back pain was selected. Patients received a therapeutic exercise protocol, including auto-mobilization exercises for the neck and lumbar regions, as well as core stabilization exercises. Pain intensity and disability were evaluated before and after the therapeutic exercise protocol. RESULTS: Statistically significant differences (p < 0.05) were shown in pain intensity and disability for patients with non-specific neck and low-back pain, with an effect size from moderate to large. CONCLUSIONS: A therapeutic exercise protocol may provide beneficial effects upon disability and pain intensity in patients with chronic non-specific back pain, including neck and low-back pain conditions In addition, It could be considered for inclusion as a back-pain-approach program in primary healthcare.

14.
Harmful Algae ; 127: 102478, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37544678

RESUMO

Public awareness about Benthic Harmful Algal Blooms (BHABs) and their negative impacts has increased substantially over the past few decades. Even so, reports of BHABs remain relatively scarce in South America (SA). This paper provides a comprehensive overview of the current state of knowledge on BHABs in the continent, by integrating data from published articles, books, and technical reports. We recorded ∼300 different occurrences of potentially toxic BHAB species over the Caribbean, Atlantic and Pacific coasts, mostly in marine (>95%) but also in estuarine areas located from 12°36' N to 54°53' S. Over 70% of the data was published/released within the past 10 years, and ∼85% were concentrated in Brazil, Venezuela, Ecuador and Colombia. Benthic species were mainly associated with macroalgae, seagrass and sediment. Incidental detection in the plankton was also relevant, mainly in places where studies targeting BHAB species are still rare, like Argentina, Uruguay, Chile and Peru. The study listed 31 infrageneric taxa of potentially toxic benthic dinoflagellates and eight of estuarine cyanobacteria occurring in SA, with the greatest species diversity recorded in the equatorial-tropical zone, mainly in northeastern Brazil (Atlantic), Venezuela and Colombia (Caribbean), and the Galapagos Islands, Ecuador (Pacific). Local strains of Amphidinium, Gambierdiscus, Coolia and Prorocentrum spp. produced toxic compounds of emerging concern. Prorocentrum lima species complex was the most common and widely distributed taxon, followed by Ostreopsis cf. ovata. In fact, these two dinoflagellates were associated with most BHAB events in SA. Whereas the former has caused the contamination of multiple marine organisms and cases of Diarrhetic Shellfish Poisoning in subtropical and temperate areas, the latter has been associated with faunal mortalities and is suspected of causing respiratory illness to beach users in tropical places. Ciguatera Poisoning has been reported in Colombia (∼240 cases; no deaths) and Venezuela (60 cases; two deaths), and may be also a risk in other places where Gambierdiscus spp. and Fukuyoa paulensis have been reported, such as the Galapagos Islands and the tropical Brazilian coast. Despite the recent advances, negative impacts from BHABs in SA are intensified by limited research/training funding, as well as the lack of official HAB monitoring and poor analytical capability for species identification and toxin detection in parts of the continent.


Assuntos
Ciguatera , Dinoflagellida , Microalgas , Proliferação Nociva de Algas , Brasil
15.
Mar Pollut Bull ; 193: 115214, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37385183

RESUMO

Phytoplankton succession is related to hydroclimatic conditions. In this study we provide the first description of a toxic phytoplankton succession in the Patagonian Fjord System. The shift was modulated by atmospheric-oceanographic forcing and consisted of the replacement of the marine dinoflagellate Dinophysis acuta in a highly stratified water column during austral summer by the diatom Pseudo-nitzschia calliantha in a mixed water column during late summer and early autumn. This transition, accompanied by a change in the biotoxin profiles (from lipophilic dinophysis toxins to hydrophilic domoic acid), was induced by the arrival of an intense atmospheric river. The winds in Magdalena Sound may have been further amplified, due to its west-east orientation and its location within a tall, narrow mountain canyon. This work also documents the first known appearance of toxic P. calliantha in Northern Patagonian. The potential impacts of the biotoxins of this species on higher trophic levels are discussed.


Assuntos
Diatomáceas , Dinoflagellida , Fitoplâncton , Toxinas Marinhas , Rios , Água
16.
J Phycol ; 59(4): 725-737, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37232027

RESUMO

Coolia species are epiphytic and benthic dinoflagellates with a cosmopolitan distribution in tropical and subtropical areas. In the austral summer of 2016, during a survey in Bahía Calderilla, a dinoflagellate of the genus Coolia was detected in macroalgae samples, and a clonal culture was established. Subsequently, the cultured cells were observed by scanning electron microscopy (SEM) and identified as C. malayensis based on their morphological characteristics. Phylogenetic analyses based on the LSU rDNA D1/D2 regions confirmed that strain D005-1 corresponded to C. malayensis and clustered with strains isolated from New Zealand, Mexico, and Asia Pacific countries. Although the strain D005-1 culture did not contain yessotoxin (YTX), cooliatoxin, 44-methyl gambierone, or its analogs in detectable amounts by LC-MS/MS, more research is needed to evaluate its toxicity and to determine the possible impact of C. malayensis in northern Chilean waters.


Assuntos
Dinoflagellida , Monitoramento Ambiental , Dinoflagellida/classificação , Oceano Pacífico , Espectrometria de Massas em Tandem , Alga Marinha , Microscopia Eletrônica de Varredura
18.
Animals (Basel) ; 13(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37106979

RESUMO

Massive mortalities in farmed larvae of the scallop Argopecten purpuratus have been associated with pathogenic Vibrio outbreaks. An energetic trade-off between development-associated demands and immune capacity has been observed. Given that highly unsaturated fatty acids (HUFAs) are essential nutrients for larval development, we evaluated the effect of diets based on microalgae low and high in HUFAs (LH and HH, respectively) on the energetic condition and the immune response of scallop larvae. The results showed that the HH diet increased cellular membrane fluidity in veliger larvae. The routine respiration rate was 64% higher in the HH-fed veligers than in the LH-fed veligers. Additionally, the metabolic capacity tended to be higher in the HH-fed veligers than in the LH-fed veligers after the Vibrio challenge. After the challenge, the HH-fed veligers presented higher transcript induction of ApTLR (immune receptor) and ApGlys (immune effector) genes, and the HH-fed pediveligers presented higher induction of ApLBP/BPI1 (antimicrobial immune effector) gene, than the LH-fed larvae. Furthermore, the HH-fed veligers controlled total Vibrio proliferation (maintaining near basal levels) after the bacterial challenge, while the LH-fed veligers were not able to control this proliferation, which increased three-fold. Finally, the HH-fed larvae showed 20-25% higher growth and survival rates than the LH-fed veligers. Overall, the results indicated that the administration of a HH diet increases cell membrane fluidity and energy metabolic capacity, which in turn enhances immunity and the ability to control Vibrio proliferation. The administration of microalgae high in HUFAs would be a promising strategy for improving scallop larval production efficiency.

19.
BMC Pulm Med ; 23(1): 114, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041499

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis is thought to result from aberrant post-injury activation of epithelial cells leading to fibroblast proliferation and activation. A number of genetic aetiologies have been implicated in this disease process, including, among others, the short telomere syndromes. Short telomere syndromes follow an autosomal dominant pattern of inheritance resulting in shortened telomere length, which consequently leads to accelerated cell death. Organs with rapid cell turnover are most affected. CASE PRESENTATION: We describe a case of a 53-year-old man with a chief complaint of cough and dyspnea on exertion. His presentation was otherwise significant for features of accelerated aging, including a history of osteoporosis and early greying, and a family history of pulmonary fibrosis in his father. Pulmonary function testing revealed a restrictive pattern with severely reduced diffusion capacity and high resolution CT of the chest showed diffuse lung disease with mild fibrosis, in pattern suggesting an alternative diagnosis to IPF. Biopsy of the lung was in keeping with chronic fibrosing interstitial pneumonia. Imaging of the abdomen showed splenomegaly, hepatic cirrhosis and portal hypertension. Transthoracic contrast echocardiogram showed intrapulmonary shunting consistent with hepatopulmonary syndrome. Given the constellation of early aging, idiopathic pulmonary fibrosis, cryptogenic cirrhosis and a family history of pulmonary fibrosis in this patient, the Short Telomere Syndrome was suspected. Peripheral blood was sent for Flow-cytometry FISH, which demonstrated granulocyte telomere length below the 10th percentile for the patient's age, consistent with a diagnosis of Short Telomere Syndrome in this clinical context. Targeted genetic testing of mutations known to be associated with short telomere was negative though it was acknowledged that the full spectrum of disease-causing mutations remains unknown. Given the extensive fibrosis on biopsy and his progressive hypoxemia he was treated with mycophenolate and prednisone. Ultimately, he developed progressive respiratory failure and underwent double lung and concurrent liver transplant 18 months after the initial diagnosis was made. CONCLUSIONS: Short Telomere Syndrome is a rare cause of end stage organ disease and testing lacks sensitivity making diagnosis challenging. Organ transplant is still the mainstay of treatment. Nevertheless, disease identification is important because of implications for family member screening and the possibility of future treatment options.


Assuntos
Síndrome Hepatopulmonar , Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Masculino , Humanos , Síndrome Hepatopulmonar/complicações , Síndrome Hepatopulmonar/terapia , Encurtamento do Telômero , Telômero , Cirrose Hepática/complicações , Fibrose , Fibrose Pulmonar Idiopática/complicações , Doenças Pulmonares Intersticiais/complicações
20.
Mar Drugs ; 21(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36827105

RESUMO

Dinophysis acuminata and D. acuta, which follows it seasonally, are the main producers of lipophilic toxins in temperate coastal waters, including Southern Chile. Strains of the two species differ in their toxin profiles and impacts on shellfish resources. D. acuta is considered the major cause of diarrhetic shellfish poisoning (DSP) outbreaks in Southern Chile, but there is uncertainty about the toxicity of D. acuminata, and little information on microscale oceanographic conditions promoting their blooms. During the austral summer of 2020, intensive sampling was carried out in two northern Patagonian fjords, Puyuhuapi (PUY) and Pitipalena (PIT), sharing D. acuminata dominance and D. acuta near detection levels. Dinophysistoxin 1 (DTX 1) and pectenotoxin 2 (PTX 2) were present in all net tow samples but OA was not detected. Although differing in hydrodynamics and sampling dates, D. acuminata shared behavioural traits in the two fjords: cell maxima (>103 cells L-1) in the interface (S ~ 21) between the estuarine freshwater (EFW)) and saline water (ESW) layers; and phased-cell division (µ = 0.3-0.4 d-1) peaking after dawn, and abundance of ciliate prey. Niche analysis (Outlying Mean Index, OMI) of D. acuta with a high marginality and much lower tolerance than D. acuminata indicated an unfavourable physical environment for D. acuta (bloom failure). Comparison of toxin profiles and Dinophysis niches in three contrasting years in PUY-2020 (D. acuminata bloom), 2018 (exceptional bloom of D. acuta), and 2019 (bloom co-occurrence of the two species)-shed light on the vertical gradients which promote each species. The presence of FW (S < 11) and thermal inversion may be used to provide short-term forecasts of no risk of D. acuta blooms and OA occurrence, but D. acuminata associated with DTX 1 pose a risk of DSP events in North Patagonian fjords.


Assuntos
Dinoflagellida , Intoxicação por Frutos do Mar , Humanos , Toxinas Marinhas/análise , Estuários , Ácido Okadáico/análise
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