ABSTRACT Meiofauna is a guild of microscopic organisms (delimited by the mesh width of two sieves, upper 500 μm and lower 44 μm) that inhabit the sediment grains and periphyton of aquatic ...environments (both freshwater and marine). Despite the fact that this definition is based on size, all the environments inhabited by these microorganisms present similar ecological challenges, which suggests that the meiofauna is a biologically and ecologically independent entity. Currently, meiofaunal organisms are represented in 23 of the 34 known metazoan phyla, including Tardigrada, Gastrotricha, and Kinorhyncha. The goal of this study was to compile information on the diversity and distribution of these phyla in Brazil. Based on the taxonomic contributions published until July 2023, a total of 97 Tardigrada species, 88 Gastrotricha species, and five Kinorhyncha species have been recorded. They are distributed throughout five biomes, eight hydrographic regions, 10 terrestrial biogeographic provinces, three marine biogeographical provinces, and 15 political states in Brazil. The species accumulation curve suggests that there are still many Tardigrada and Gastrotricha species to be discovered with increasing sampling effort, as the rate of discovery of new species is linearly increasing. Unfortunately, knowledge of the biodiversity of these meiofaunal groups is still limited due to sparse information on identity and distribution. We recommend future studies dealing with meiofauna taxa to prioritize redescribing endemic species based on integrative taxonomy and increase the number of the type series deposited in Zoological Museums (e.g., specimen photos). Furthermore, the training of researchers specialized in these taxa is a priority, as some of these phyla do not have any Brazilian specialists.
Lymphangioleiomyomatosis (LAM) is a rare systemic disease that typically presents like cystic lung disease. High-resolution computed tomography (CT) is the recommended imaging technique, with cysts ...being the hallmark: typically multiple, well-circumscribed, thin-walled, with a variable diameter (usually <2 cm) and widespread in distribution. The gold standard for diagnosis is a biopsy. LAM should be considered in the differential diagnosis of cystic lung diseases.The authors report a case of LAM presenting with a pneumothorax, which due to its atypical imaging characteristics, mimicked another uncommon cystic disease. A multidisciplinary approach is crucial when dealing with presentations of rare diseases.
Predicting and measuring changes resulting from marine protected areas (MPAs) has posed a challenge for practitioners, partly because ecosystems are complex and can change in unanticipated ways, but ...also due to MPA characteristics such as design factors, conservation objectives (COs), and monitoring programs, that can leave little chance of meeting stated goals. We consider these design factors for the Laurentian Channel MPA, a large offshore Canadian protected area established to protect against fishing impacts. Specifically, in this study we evaluated (1) whether it is realistic to expect improvements in the MPA for four previously established taxa‐specific COs, and (2) whether existing scientific surveys are capable of detecting changes in these CO taxa even if they occurred. Three CO species were sampled in scientific multispecies research vessel trawl surveys (Black Dogfish, Smooth Skate, and Northern Wolffish) and a fourth CO, sea pen taxa, were enumerated using seafloor imagery. Simulations indicate that trawl surveys have very little chance of detecting change in the abundance of the three fish species examined, while seafloor imagery data had higher statistical power for sea pen taxa. Moreover, we show that expecting change related to the removal of fishing is unrealistic due to the fact that the MPA was established in an area of minimal fishing pressure. While positive change is unlikely to be induced by the MPA, or be detected if they occurred, this MPA could provide conservation benefits if COs and monitoring approaches were realigned to match the unique features of this area that represents largely unimpacted sensitive benthic habitats.
Marine protected areas (MPAs) are being created to protect against the loss of biodiversity in the world's oceans. Simulation modelling and power analysis to evaluate likelihood that MPAs are effective in reaching their established goals is important to ensure conservation efforts are effective.
SARS-CoV-2 infection in children is usually asymptomatic/mild. However, some patients may develop critical forms. We aimed to describe characteristics and evaluate the factors associated to ...in-hospital mortality of patients with critical COVID-19/MIS-C in the Amazonian region. This multicenter prospective cohort included critically ill children (1 mo-18 years old), with confirmed COVID-19/MIS-C admitted to 3 tertiary Pediatric Intensive Care Units (PICU) in the Brazilian Amazon, between April/2020 and May/2023. The main outcome was in-hospital mortality and were evaluated using a multivariable Cox proportional regression. We adjusted the model for pediatric risk of mortality score version IV (PRISMIV) score and age/comorbidity. 266 patients were assessed with 187 in the severe COVID-19 group, 79 included in the MIS-C group. In the severe COVID-19 group 108 (57.8%) were male, median age was 23 months, 95 (50.8%) were up to 2 years of age. Forty-two (22.5%) patients in this group died during follow-up in a median time of 11 days (IQR, 2-28). In the MIS-C group, 56 (70.9%) were male, median age was 23 months and median follow-up was 162 days (range, 3-202). Death occurred in 17 (21.5%) patients with a median death time of 7 (IQR, 4-13) days. The mortality was associated with higher levels of Vasoactive Inotropic-Score (VIS), presence of acute respiratory distress syndrome (ARDS), higher levels of Erythrocyte Sedimentation Rate, (ESR) and thrombocytopenia. Critically ill patients with severe COVID-19 and MIS-C from the Brazilian Amazon showed a high mortality rate, within 12 days of hospitalization.
Many reef fishes move between different coastal systems throughout their ontogeny, but these movements are complex and often not understood. In this study, we examined how the dog snapper (Lutjanus ...jocu) uses marine and estuarine habitats across the Abrolhos Bank shelf (eastern Brazil) through the analysis of elemental signatures in otoliths. Specimens were sampled in an estuary and adjacent marine region. Ba/Ca, Sr/Ca, Mg/Ca and Mn/Ca were measured by LA-ICPMS along the otolith growth axis to cover the entire lifetime of the individual. Change-point analysis, principal component analysis and BRT modeling were used for the objective identification of habitat-use patterns of the species. Otolith Ba/Ca ratios performed better than other elements for tracking L. jocu movements between estuarine and marine habitats, which may result from small variations in salinity and high turbidity levels, as these characteristics are typical of the Abrolhos Bank. Two contrasting habitat-use patterns were identified for L. jocu: i) marine residents (56% of sampled fish) - fish that remain in marine systems throughout their lifetime; and ii) marine migrants (37%) - juveniles inhabit estuaries and move to marine systems with age. These categories were successfully re-classified, which suggests that they are coherent and reliable. Following recent findings of flexible habitat-use patterns in many other fish species, L. jocu habitat requirements also appear to be quite malleable. As the dog snapper has been facing commercial overexploitation in the region, this plasticity in habitat use should be considered in future fisheries management.
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•Habitat use by Lutjanus jocu was assessed through otolith chemistry analysis.•Two contrasting patterns were inferred by otolith Ba/Ca ratios.•Marine residents and marine migrants were the identified patterns.•This habitat use plasticity should be considered in future fisheries management.
Caatinga is highly influenced by its seasonality. This species is endemic in the northeastern region, which is rich in plants with pharmacological potential. Many of these plants are used by the ...population and some of them have confirmed pharmacological properties. Mimosa caesalpiniifolia Benth. (Mimosaceae) is a native plant from northeastern Brazil׳s caatinga, popularly known as sabiá and cascudo. The tea from the inflorescence of this species is used by the population of the semi-arid for the treatment of hypertension, and the utilization of the plant bark for the staunching of bleedings and wound washing in order to prevent inflammation; also, the ingestion of the bark infusion is used in the treatment of bronchitis. However, its pharmacological effects and mechanisms of action have not yet been studied. The aim of the present study was to determine the effect of the ethanolic extract of M. caesalpiniifolia on the cardiovascular system in rats.
In a study for the assessment of the hypotensive effect of the extract, the polyethylene catheters were inserted in the aorta artery and inferior vena cava for the measurement of the arterial pressure and heart rate. When intragastric administration was performed, only one catheter was implanted in the abdominal aorta. In studies for the vasorelaxant activity, mesenteric arterial rings (1–2mm) were used: they were kept in Tyrode׳s solution (95% O2 and 5% CO2) and submitted to tension of 0.75g/f for 1h. The results were expressed as mean±S.E.M., significant to the values of p<0.05.
The administration of the doses through venous pathway (6.25; 12.5 and 25mg/kg, i.v.) promoted hypotension followed by bradycardia in the higher doses. The pre-treatment with atropine (2mg/kg, i.v.) interrupted both the hypotension and the bradycardia; with hexamethonium, hypotension was reverted and bradycardia was attenuated. While the administration of tea/flowers (25mg/kg i.v.) also promoted a following section of hypotension, a slight increase in heart rate was observed. When administered orally, MC-EtOH/flowers (100mg/kg, v.o.) promoted a decrease in the arterial pressure from 90min on, without a significant alteration in the heart rate in relation to the control. In the in vitro study, a pharmacological trial was performed with the extracts obtained from parts of the species M. caesalpiifolia (leaves, bark, fruit and inflorescences). Among all extracts tested, the ethanolic extract from the inflorescences (MC-EtOH/flowers) presented higher vasorelaxant potency in relation to the other parts of the plant. Henceforth, MC-EtOH/flowers was used in the sequence. In mesenteric preparations pre-contracted with phenylephrine (10−5M), the MC-EtOH/flowers (0.1–750µg/ml) promoted vasorelaxant effect regardless of the vascular endothelium. MC-EtOH/flowers inhibited the contractions induced by the cumulative addition of phenylephrine (10−9–10−5mol/l) or CaCl2 (10−6–3×10−2M), in a concentration-dependent way. In contractions induced by S(-)Bay K 8644, a Cav-L activator, the MC-EtOH/flowers promoted concentration-dependent relaxation, corroborating previous results.
The tea of flowers of M. caesalpiniifolia promotes hypotension and tachycardia, whereas ethanolic extract (MC-EtOH) promotes hypotension and bradycardia involving the participation of the muscarinic and ganglionic pathways, as well as vasorelaxant action involving the Ca2+ influx inhibition blockade.
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Numerous aromatic biomarkers such as aromatic carotenoids and aryl isoprenoids have been reported in Brazilian Cretaceous oils. The n-alkyl aromatics such as n-alkyl benzenes (ϕ-C n ), toluenes (ϕT-C ...n ), xylenes, and mesitylenes have also been detected in geological samples and can be valuable tools in geochemical and environmental investigations. In this work, comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC–TOFMS) and GC–tandem MS (GC–MS/MS) were applied to identify the alkyl aromatic series in two crude oils from the Sergipe-Alagoas Basin, Brazil. Geochemical characteristics indicate a different depositional paleoenvironment for each sample, marine and lacustrine end-members. Aromatic compounds were identified using full mass spectrum information, diagnostic ions (i.e., m/z 92 for alkylbenzenes and m/z 106 for alkyltoluenes), selected reaction monitoring transitions, and coinjection with an authentic C21 n-pentadecylbenzene standard. The Sergipe-Alagoas oils presented a series of n-alkylbenzenes and n-alkyltoluenes ranging from ϕ-C7 to ϕ-C33 and ϕT-C7 to ϕT-C30, respectively. In addition, phytanyl arenes and a new series of α,ω-bisphenylalkanes were identified for the first time in Sergipe-Alagoas oils. The n-alkylbenzene profile for marine crude oil resembles that of n-alkanes and n-alkylcyclohexanes, which suggests that they may have the same precursors. The investigation of aromatic fractions and detection of n-alkyl aromatic hydrocarbons in Brazilian Cretaceous oils provide new assignments to the contribution of organic matter and its geochemical significance.
Ethanol is used routinely to dilute cell culture media supplements with little or no water solubility. This study evaluates the effect of low concentration of ethanol on the follicular development, ...oocyte maturation, hormone production, gene expression, and metabolomics profile of spent culture medium after long-term culture of isolated ovine preantral follicles. For this, follicles were cultured for 18 days in α-Minimum Essential Medium+ alone (control treatment) or supplemented with 100 ng/mL recombinant bovine FSH (rbFSH treatment) or with 0.2%-v/v ethanol (ethanol treatment). Ethanol treatment increased the percentage of degenerated follicles and oocytes significantly, however, it showed the highest estradiol secretion. Also, the rate of meiosis resumption was higher in ethanol treatment than Control treatment. Ethanol treatment decreased the mRNA levels of B-cell lymphoma 2 (BCL2), BCL2 associated X, Aquaporin 3, Connexin 43, Inhibin Subunit Beta A, kit ligand, Heat Shock Protein (HSP A1A) significantly when compared to the Control treatment. However, mRNA levels of cytochrome P450 family 19, and FSH receptors were significantly higher in ethanol treatment than in the Control treatment. The levels of some metabolites, which are likely amino acids, lipids, an analog of Cyclic guanosine monophosphate, and a derivative of phosphoinositol phosphate metabolism, had higher relative concentrations in ethanol and rbFSH treatments than the Control treatment. In conclusion, ethanol addition augmented the follicular and oocyte degeneration rates but increased the estradiol production and the meiotic resumption. Furthermore, the follicular metabolomic profile was similar between ethanol and rbFSH treatments being both treatments; however, different from the Control treatment.
•Ethanol increases the number of degenerated oocytes and follicles.•Ethanol affects mRNA expression in cultured preantral follicles.•Ethanol raises the estradiol production and oocyte meiotic resumption.•Grain ethanol affects the follicular metabolomics profile.
The current therapy for leishmaniasis, which affects annually about 2 million people, is far from satisfactory. All available drugs require parenteral administration and are potentially toxic. Plant ...essential oils have been traditionally used in folk medicine and appear as valuable alternative source for chemotherapeutic compounds. In this study, we demonstrated the effect of essential oils from Cymbopogon citratus, Lippia sidoides, and Ocimum gratissimum on growth and ultrastructure of Leishmania chagasi promastigote forms. Steam distillation was used to isolate the essential oils, and their constituents were characterized by gas chromatography coupled to mass spectrometry and nuclear magnetic resonance. All essential oils showed in vitro inhibitory action on L. chagasi promastigotes growth in a dose-dependent way, with IC₅₀/72 h of 45, 89, and 75 μg/mL for C. citratus, L. sidoides, and O. gratissimum, respectively. Drastic morphological alterations were observed in all essential oil-treated parasites, including cell swelling, accumulation of lipid droplets in the cytoplasm, and increase of acidocalcisome volume. Furthermore, aberrant-shaped cells with multi-septate body were observed by scanning electron microscopy, suggesting an additional effect on cytokinesis. Taken together, our data show that these essential oils affect the parasite viability being the C. citratus essential oil the most effective against L. chagasi.
Ultraviolet and blue light were obtained by nonlinear frequency conversion in a random laser (RL) based on Nd0.10Y0.90Al3(BO3)4 nanocrystalline powder. RL operation at 1062 nm, due to the (4)F3/2 → ...(4)I11/2 transition of neodymium ions (Nd(3+)), was achieved by exciting the Nd(3+) with a tunable beam from 680 to 920 nm covering the ground state absorption transitions to the (4)F9/2, ((4)F7/2,(4)S3/2), ((4)F5/2,(2)H9/2), and (4)F3/2 states. Light from 340 to 460 nm was obtained via the second-harmonic generation of the excitation beam while tunable blue light, from 417 to 486 nm, was generated by self-sum-frequency mixing between the excitation beam and the RL emission.
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