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1.
PLoS One ; 19(6): e0305566, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38875290

RESUMO

INTRODUCTION: In the Netherlands, most emergency department (ED) patients are referred by a general practitioner (GP) or a hospital specialist. Early risk stratification during telephone referral could allow the physician to assess the severity of the patients' illness in the prehospital setting. We aim to assess the discriminatory value of the acute internal medicine (AIM) physicians' clinical intuition based on telephone referral of ED patients to predict short-term adverse outcomes, and to investigate on which information their predictions are based. METHODS: In this prospective study, we included adult ED patients who were referred for internal medicine by a GP or a hospital specialist. Primary outcomes were hospital admission and triage category according to the Manchester Triage System (MTS). Secondary outcome was 31-day mortality. The discriminatory performance of the clinical intuition was assessed using an area under the receiver operating characteristics curve (AUC). To identify which information is important to predict adverse outcomes, we performed univariate regression analysis. Agreement between predicted and observed MTS triage category was assessed using intraclass and Spearman's correlation. RESULTS: We included 333 patients, of whom 172 (51.7%) were referred by a GP, 146 (43.8%) by a hospital specialist, and 12 (3.6%) by another health professional. The AIM physician's clinical intuition showed good discriminatory performance regarding hospital admission (AUC 0.72, 95% CI: 0.66-0.78) and 31-day mortality (AUC 0.73, 95% CI: 0.64-0.81). Univariate regression analysis showed that age ≥65 years and a sense of alarm were significant predictors. The predicted and observed triage category were similar in 45.2%, but in 92.5% the prediction did not deviate by more than one category. Intraclass and Spearman's correlation showed fair agreement between predicted and observed triage category (ICC 0.48, Spearman's 0.29). CONCLUSION: Clinical intuition based on relevant information during a telephone referral can be used to accurately predict short-term outcomes, allowing for early risk stratification in the prehospital setting and managing ED patient flow more effectively.


Assuntos
Medicina Interna , Encaminhamento e Consulta , Telefone , Triagem , Humanos , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Triagem/métodos , Serviço Hospitalar de Emergência , Países Baixos , Médicos , Intuição , Adulto , Idoso de 80 Anos ou mais , Curva ROC
2.
Artigo em Inglês | MEDLINE | ID: mdl-38895981

RESUMO

Retinol saturase (RetSat) is an oxidoreductase involved in lipid metabolism and the cellular sensitivity to peroxides. RetSat is highly expressed in metabolic organs like liver and adipose tissue and its global loss in mice increases body weight and adiposity. The regulation of RetSat expression and its function in the intestine are unexplored. Here, we show that RetSat is present in different segments of the digestive system, localizes to intestinal epithelial cells, and is upregulated by feeding mice high-fat diet (HFD). Intestine-specific RetSat deletion in adult mice did not affect nutrient absorption and energy homeostasis basally, but lowered body weight gain and fat mass of HFD-fed mice, potentially via increasing locomotor activity. Moreover, jejunal expression of genes related to ß-oxidation and cholesterol efflux were decreased and colonic cholesterol content reduced upon RetSat deletion. In colitis, which we show to downregulate intestinal RetSat expression in humans and mice, RetSat ablation improved epithelial architecture of the murine colon. Thus, intestinal RetSat expression is regulated by dietary interventions and inflammation, and its loss reduces weight gain upon HFD-feeding and alleviates epithelial damage upon injury.

3.
EMBO Rep ; 25(7): 2878-2895, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38769419

RESUMO

Vitamin A (retinol) is distributed via the blood bound to its specific carrier protein, retinol-binding protein 4 (RBP4). Retinol-loaded RBP4 is secreted into the circulation exclusively from hepatocytes, thereby mobilizing hepatic retinoid stores that represent the major vitamin A reserves in the body. The relevance of extrahepatic retinoid stores for circulating retinol and RBP4 levels that are usually kept within narrow physiological limits is unknown. Here, we show that fasting affects retinoid mobilization in a tissue-specific manner, and that hormone-sensitive lipase (HSL) in adipose tissue is required to maintain serum concentrations of retinol and RBP4 during fasting in mice. We found that extracellular retinol-free apo-RBP4 induces retinol release by adipocytes in an HSL-dependent manner. Consistently, global or adipocyte-specific HSL deficiency leads to an accumulation of retinoids in adipose tissue and a drop of serum retinol and RBP4 during fasting, which affects retinoid-responsive gene expression in eye and kidney and lowers renal retinoid content. These findings establish a novel crosstalk between liver and adipose tissue retinoid stores for the maintenance of systemic vitamin A homeostasis during fasting.


Assuntos
Adipócitos , Jejum , Proteínas Plasmáticas de Ligação ao Retinol , Esterol Esterase , Vitamina A , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol/genética , Animais , Vitamina A/metabolismo , Vitamina A/sangue , Jejum/metabolismo , Camundongos , Adipócitos/metabolismo , Esterol Esterase/metabolismo , Esterol Esterase/genética , Fígado/metabolismo , Tecido Adiposo/metabolismo , Camundongos Knockout , Camundongos Endogâmicos C57BL
4.
Biol Res ; 57(1): 12, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561836

RESUMO

BACKGROUND: Bacterial aromatic degradation may cause oxidative stress. The long-chain flavodoxin FldX1 of Paraburkholderia xenovorans LB400 counteracts reactive oxygen species (ROS). The aim of this study was to evaluate the protective role of FldX1 in P. xenovorans LB400 during the degradation of 4-hydroxyphenylacetate (4-HPA) and 3-hydroxyphenylacetate (3-HPA). METHODS: The functionality of FldX1 was evaluated in P. xenovorans p2-fldX1 that overexpresses FldX1. The effects of FldX1 on P. xenovorans were studied measuring growth on hydroxyphenylacetates, degradation of 4-HPA and 3-HPA, and ROS formation. The effects of hydroxyphenylacetates (HPAs) on the proteome (LC-MS/MS) and gene expression (qRT-PCR) were quantified. Bioaugmentation with strain p2-fldX1 of 4-HPA-polluted soil was assessed, measuring aromatic degradation (HPLC), 4-HPA-degrading bacteria, and plasmid stability. RESULTS: The exposure of P. xenovorans to 4-HPA increased the formation of ROS compared to 3-HPA or glucose. P. xenovorans p2-fldX1 showed an increased growth on 4-HPA and 3-HPA compared to the control strain WT-p2. Strain p2-fldX1 degraded faster 4-HPA and 3-HPA than strain WT-p2. Both WT-p2 and p2-fldX1 cells grown on 4-HPA displayed more changes in the proteome than cells grown on 3-HPA in comparison to glucose-grown cells. Several enzymes involved in ROS detoxification, including AhpC2, AhpF, AhpD3, KatA, Bcp, CpoF1, Prx1 and Prx2, were upregulated by hydroxyphenylacetates. Downregulation of organic hydroperoxide resistance (Ohr) and DpsA proteins was observed. A downregulation of the genes encoding scavenging enzymes (katE and sodB), and gstA and trxB was observed in p2-fldX1 cells, suggesting that FldX1 prevents the antioxidant response. More than 20 membrane proteins, including porins and transporters, showed changes in expression during the growth of both strains on hydroxyphenylacetates. An increased 4-HPA degradation by recombinant strain p2-fldX1 in soil microcosms was observed. In soil, the strain overexpressing the flavodoxin FldX1 showed a lower plasmid loss, compared to WT-p2 strain, suggesting that FldX1 contributes to bacterial fitness. Overall, these results suggest that recombinant strain p2-fldX1 is an attractive bacterium for its application in bioremediation processes of aromatic compounds. CONCLUSIONS: The long-chain flavodoxin FldX1 improved the capability of P. xenovorans to degrade 4-HPA in liquid culture and soil microcosms by protecting cells against the degradation-associated oxidative stress.


Assuntos
Burkholderia , Burkholderiaceae , Flavodoxina , Gliceraldeído/análogos & derivados , Fenilacetatos , Propano , Biodegradação Ambiental , Flavodoxina/metabolismo , Flavodoxina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteoma/metabolismo , Proteoma/farmacologia , Cromatografia Líquida , Burkholderia/genética , Burkholderia/metabolismo , Espectrometria de Massas em Tandem , Estresse Oxidativo , Glucose/metabolismo , Solo
5.
J Invertebr Pathol ; 204: 108112, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38631556

RESUMO

Trematodes of the genus Leucochloridium exhibit an unusual transmission strategy among mollusks (intermediate host). The fully developed sporocyst, housing encysted metacercariae, displays vivid coloration and rhythmic activity in the snail's tentacle, mimicking insect larvae. These strategies attract insectivorous birds, their final hosts, thereby increasing the chances of completing their life cycle. In South America, the reports of adults and larval stages of Leucochloridium are scarce. Brown-banded broodsac of Leucochloridium sp. were obtained from Omalonyx unguis collected in a shallow lake from Corrientes Province, Argentina. Here, we morphologically characterized the larval stages (broodsac and metacercaria), identified the parasite through DNA sequences from nuclear 28S-rRNA (28S) and the mitochondrial cytochrome c oxidase I (COI) genes, and explored its evolutionary affinities with the Leucochloridium species available in GenBank. The present broodsac displays brown bands, with a yellowish background in the first two-thirds and yellowish-white in the last third. Based on morphological comparisons, the broodsac and metacercaria described in this study could not be conclusively categorized under any known South American species of Leucochloridium. In relation to the phylogenetic reconstructions, Leucochloridium sp. consistently clustered with L. perturbatum, and species delimitation analyses resulted in recognized Leucochloridium sp. from Argentina as a distinct species. The DNA sequences obtained in this study constitute the first genetic data generated for sporocyst broodsacs in South America. Future studies, incorporating morphology, genetic, and biological data, will be essential for both species identification and the elucidation of leucochloridiid diversity in the region.


Assuntos
Trematódeos , Animais , Argentina , Trematódeos/genética , Trematódeos/fisiologia , Trematódeos/anatomia & histologia , Metacercárias , Filogenia , Gastrópodes/parasitologia , RNA Ribossômico 28S/genética , RNA Ribossômico 28S/análise
6.
Front Psychol ; 15: 1325188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505362

RESUMO

In Mexico, shamans are recognized for the gift of entering a deep trance that allows them to know the origin of the diseases and conflicts that afflict people. They commonly treat patients through limpias (cleansing) to extract negative elements sent by a witch or that were "collected" in places that harbor "evil winds." We present a case study of an 81-year-old Mexican shaman who noticed her gift in childhood. Electroencephalographic recordings were made while the shaman performed three activities: reading cards to diagnose a patient and answer the questions he posed; limpia with chicken eggs, stones, and bells to absorb adverse "things"; and the incorporation trance through which the deceased is believed to occupy the shaman's body to use it as a communication channel. Alpha activity was observed when concentrated, suggesting a hypnagogic-like state. Predominant beta and gamma oscillations were observed, suggesting a potential plastic phenomenon that modulates the assimilation of external and internal referents guiding temporal schemes for action, attention, and the integration of mnemonic, sensory, and imaginative elements. We used a neuroanthropological approach to understand shamanic trance as a biological potential of the human brain to induce non-ordinary states of consciousness linked to cultural beliefs and practices.

7.
Mem Inst Oswaldo Cruz ; 119: e230149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359306

RESUMO

BACKGROUND: American tegumentary leishmaniasis (ATL) is an endemic neglected tropical disease (NTD), its conventional treatment is toxic, slow, and invasive. Rapid diagnosis is crucial for the clinical management of suspected patients, so the development and use of low-cost, miniaturised and portable devices could be the key. OBJECTIVES: This work aimed to develop a simple paper-based electrochemical platform for the serological detection of ATL. METHODS: Platform was fabricated in Whatman N°1 paper, contains a hydrophobic zone generated by wax printing, two pencil graphite electrodes, and uses specific crude extracts (CA) antigens for ATL immuno-determination. The platform performance was analysed by measuring the relative impedance change for different antigen-antibody combinations. Then, 10 serum human samples previously diagnosed by the gold standard (five positive ATL cases and five non-ATL cases) were evaluated. FINDINGS: The platform presented a linear response for the charge transfer resistance (ΔRct) and the interface reactance (ΔXc). Also, optimal working conditions were established (1/60 serum dilution and 180 µg/mL CA concentration). Then, the platform permits to distinguish between ATL and non-ATL (p < 0.05) human serum samples. MAIN CONCLUSIONS: Our platform could allow the diagnosis, management, and monitoring of leishmaniasis while being an extremely simple and environmentally friendly technology.


Assuntos
Leishmaniose Cutânea , Testes Sorológicos , Humanos , Leishmaniose Cutânea/diagnóstico , Testes Sorológicos/instrumentação
8.
Phys Med ; 119: 103300, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325222

RESUMO

PURPOSE: The aim of the present study, conducted by a working group of the Italian Association of Medical Physics (AIFM), was to define typical z-resolution values for different digital breast tomosynthesis (DBT) models to be used as a reference for quality control (QC). Currently, there are no typical values published in internationally agreed QC protocols. METHODS: To characterize the z-resolution of the DBT models, the full width at half maximum (FWHM) of the artifact spread function (ASF), a technical parameter that quantifies the signal intensity of a detail along reconstructed planes, was analyzed. Five different commercial phantoms, CIRS Model 011, CIRS Model 015, Modular DBT phantom, Pixmam 3-D, and Tomophan, were evaluated on reconstructed DBT images and 82 DBT systems (6 vendors, 9 models) in use at 39 centers in Italy were involved. RESULTS: The ASF was found to be dependent on the detail size, the DBT angular acquisition range, the reconstruction algorithm and applied image processing. In particular, a progressively greater signal spread was observed as the detail size increased and the acquisition angle decreased. However, a clear correlation between signal spread and angular range width was not observed due to the different signal reconstruction and image processing strategies implemented in the algorithms developed by the vendors studied. CONCLUSIONS: The analysis led to the identification of typical z-resolution values for different DBT model-phantom configurations that could be used as a reference during a QC program.


Assuntos
Processamento de Imagem Assistida por Computador , Mamografia , Mamografia/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Artefatos , Algoritmos
9.
Clin Diabetes ; 42(1): 49-55, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38230332

RESUMO

Social determinants of health (SDOH) are strongly associated with outcomes for people with type 1 diabetes. Six centers in the T1D Exchange Quality Improvement Collaborative applied quality improvement principles to design iterative Plan-Do-Study-Act cycles to develop and expand interventions to improve SDOH screening rates. The interventions tested include staff training, a social risk index, an electronic health record patient-facing portal, partnerships with community organizations, and referrals to community resources. All centers were successful in improving SDOH screening rates, with individual site improvements ranging from 41 to 70% and overall screening across the six centers increasing from a baseline of 1% to 70% in 27 months.

10.
Mol Phylogenet Evol ; 190: 107970, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37995894

RESUMO

Armored catfishes of the genus Eurycheilichthys are endemic to Southern Brazil and Misiones (Argentina) comprising nine species of small size, with a high degree of sympatry and species diversity distributed in two river basins. Here we use new genome-wide data to infer a species phylogeny and test species boundaries for this poorly known group. We estimate 1) the phylogenetic relationships of the species of Eurycheilichthys based on 29,350 loci in 65 individuals of nine species plus outgroups, and 2) the population structure and differentiation based on 43,712 loci and 62 individuals to estimate how geography may have acted on speciation and formation of the sympatric species groups. Analyses support the monophyly of the genus and suggest two species-inclusive clades (East and West) with high support and very recently diverged species. Western clade contains E. limulus (from upper Jacuí River basin) that is sister to Western species of the Taquari-Antas basin plus E. paucidens. The Eastern clade contains E. pantherinus (from Uruguay River basin) sister to the Eastern species of the Taquari-Antas basin E. coryphaenus, plus the central-distributed species E. planus and E. vacariensis, and the more widely-distributed species E. luisae. Eurycheilichthys luisae is not monophyletic and may contain one or more cryptic species or hybrid individuals. A stronger diversity on structure of lineages on the Taquari-Antas, when compared to upper Uruguay and Jacuí River basins, and the fact that most of the sympatrically distributed taxa have non-sister relationships suggest a scenario of mainly allopatric speciation and may indicate a more dynamic landscape with headwater capture events among these tributaries.


Assuntos
Peixes-Gato , Simpatria , Humanos , Animais , Filogenia , Peixes-Gato/genética , Geografia , Brasil
11.
Microbiol Resour Announc ; 13(1): e0082223, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38047652

RESUMO

Halotolerant Halomonas spp. SpR1 and SpR8 are potential plant growth-promoting bacteria (PGPB) isolated from Salicornia rhizosphere in a Chilean Altiplano hydrothermal lagoon. We report draft genomes of Halomonas sp. SpR1 (5.17Mb) and Halomonas sp. SpR8 (4.47 Mb). Both represent potentially novel independent species closely related to Halomonas boliviensis DSM 15516T.

12.
Mem. Inst. Oswaldo Cruz ; 119: e230149, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534934

RESUMO

BACKGROUND American tegumentary leishmaniasis (ATL) is an endemic neglected tropical disease (NTD), its conventional treatment is toxic, slow, and invasive. Rapid diagnosis is crucial for the clinical management of suspected patients, so the development and use of low-cost, miniaturised and portable devices could be the key. OBJECTIVES This work aimed to develop a simple paper-based electrochemical platform for the serological detection of ATL. METHODS Platform was fabricated in Whatman N°1 paper, contains a hydrophobic zone generated by wax printing, two pencil graphite electrodes, and uses specific crude extracts (CA) antigens for ATL immuno-determination. The platform performance was analysed by measuring the relative impedance change for different antigen-antibody combinations. Then, 10 serum human samples previously diagnosed by the gold standard (five positive ATL cases and five non-ATL cases) were evaluated. FINDINGS The platform presented a linear response for the charge transfer resistance (ΔRct) and the interface reactance (ΔXc). Also, optimal working conditions were established (1/60 serum dilution and 180 µg/mL CA concentration). Then, the platform permits to distinguish between ATL and non-ATL (p < 0.05) human serum samples. MAIN CONCLUSIONS Our platform could allow the diagnosis, management, and monitoring of leishmaniasis while being an extremely simple and environmentally friendly technology.

13.
J Synchrotron Radiat ; 31(Pt 1): 150-161, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117694

RESUMO

Third- and fourth-generation synchrotron light sources with high fluxes and beam energies enable the use of innovative X-ray translucent experimental apparatus. These experimental devices access geologically relevant conditions whilst enabling in situ characterization using the spatial and temporal resolutions accessible at imaging beamlines. Here, Heitt Mjölnir is introduced, a heated miniature triaxial rig based on the design of Mjölnir, but covering a wider temperature range and larger sample volume at similar pressure capacities. This device is designed to investigate coupled thermal, chemical, hydraulic and mechanical processes from grain to centimetre scales using cylindrical samples of 10 mm × 20 mm (diameter × length). Heitt Mjölnir can simultaneously reach confining (hydraulic) pressures of 30 MPa and 500 MPa of axial stress with independently controlled sample pore fluid pressure < 30 MPa. This internally heated apparatus operates to temperatures up to 573 K with a minimal vertical thermal gradient in the sample of <0.3 K mm-1. This new apparatus has been deployed in operando studies at the TOMCAT (Swiss Light Source), I12 JEEP (Diamond Light Source) and PSICHÉ (Synchrotron SOLEIL) beamlines for 4D X-ray microtomography with scan intervals of a few minutes. Heitt Mjölnir is portable and modular, allowing a wide range of 4D characterizations of low-grade metamorphism and deformational processes. It enables spatially and temporally resolved fluid-rock interaction studies at conditions of crustal reservoirs and is suitable for characterization of material properties in geothermal, carbonation or subsurface gas storage applications. Technical drawings and an operation guide are included in this publication.

14.
Mol Metab ; 79: 101855, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38128827

RESUMO

OBJECTIVE: Retinol saturase (RetSat) is an endoplasmic reticulum-localized oxidoreductase highly expressed in organs involved in lipid metabolism such as white (WAT) and brown adipose tissue (BAT). Cold exposure was shown to increase RETSAT protein in BAT but its relevance for non-shivering thermogenesis, a process with beneficial effects on metabolic health, is unknown. METHODS: We analyzed the regulation of RetSat expression in white and brown adipocytes and different murine adipose tissue depots upon ß-adrenergic stimulation and cold exposure. RetSat function during the differentiation and ß-adrenergic stimulation of brown adipocytes was dissected by loss-of-function experiments. Mice with BAT-specific deletion of RetSat were generated and exposed to cold. Gene expression in human WAT was analyzed and the effect of RetSat depletion on adipocyte lipolysis investigated. RESULTS: We show that cold exposure induces RetSat expression in both WAT and BAT of mice via ß-adrenergic signaling. In brown adipocytes, RetSat has minor effects on differentiation but is required for maximal thermogenic gene and protein expression upon ß-adrenergic stimulation and mitochondrial respiration. In mice, BAT-specific deletion of RetSat impaired acute but not long-term adaptation to cold exposure. RetSat expression in subcutaneous WAT of humans correlates with the expression of genes related to mitochondrial function. Mechanistically, we found that RetSat depletion impaired ß-agonist-induced lipolysis, a major regulator of thermogenic gene expression in adipocytes. CONCLUSIONS: Thus, RetSat expression is under ß-adrenergic control and determines thermogenic capacity of brown adipocytes and acute cold tolerance in mice. Modulating RetSat activity may allow for therapeutic interventions towards pathologies with inadequate metabolic activity.


Assuntos
Lipólise , Vitamina A , Camundongos , Humanos , Animais , Vitamina A/metabolismo , Adrenérgicos/metabolismo , Tecido Adiposo Marrom/metabolismo , Adipócitos Marrons/metabolismo , Obesidade/metabolismo
15.
ISA Trans ; 146: 592-602, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38151448

RESUMO

The walking stability of a humanoid robot is a fundamental problem due to the complex nonlinear dynamic model of the robot's legs. This work introduces the performance tracking control for the humanoid NAO robot by using a Nonlinear Disturbance Observer (NDO)-based Fixed-time Terminal Sliding Mode (FTSM). The influence of uncertain external disturbance is considered while implementing the control strategy to improve the walking motion of the NAO robot. An NDO is adapted to estimate the uncertainties and external disturbances. A novel FTSM surface is proposed to drive the tracking errors to zero in fixed-time. The designed NDO-based FTSM control law achieves robustness while reducing the chattering phenomenon. The Lyapunov's stability theory is used to establish the fixed-time stability of the sliding surface and system states under the proposed control method. To validate the performance of the proposed NDO-based FTSM control, a real-time experiment was conducted on a humanoid NAO robot to demonstrate the improved tracking performance in the presence of the uncertain perturbation effect. The effectiveness of the proposed controller design is validated on a flat, upward inclined surface, and compared to another controller.

16.
J Fish Biol ; 104(4): 1042-1053, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38149310

RESUMO

Otocinclus cocama, a uniquely colored species of the loricariid catfish genus Otocinclus described solely from the type locality in the lower Ucayali River in northern Peru, is reported occurring in the Tigre River, a tributary to the Marañón River that drains a different section of the Andean Mountain range in the western Amazon. Both populations differ in the number of dark bars spanning the flanks of the body, and we investigated whether these morphotypes constitute distinct species. The body shapes of populations from the Tigre and Ucayali rivers were compared using geometric morphometrics. Although principal component analysis detected a broad overlap between populations, multivariate analysis of variance and linear driscriminat analysis revealed a subtle differentiation between the populations of the two hydrographic basins. Average body shape of the Ucayali River population tend to be slightly higher than that of the Tigre River, with the caudal peduncle stretched vertically in the Ucayali population. Multivariate regression of shape and centroid size revealed an allometric effect of 10.7% (p < 0.001), suggesting that the variation between Tigre and Ucayali populations was purely shape variation. Molecular data of coI, cytb, nd2, and 16S mitochondrial genes indicated a nucleotide diversity range from 0.001 to 0.003, and haplotypic diversity range from 0.600 ± 0.11 to 0.79 ± 0.07. The median-joining haplotype network for the concatenated matrix exhibited two divergent haplogroups related to the geographic area and separated by <10 mutational steps. The molecular species delimitation methods based on distance (automatic barcode gap discovery and assemble species by automatic partitioning) recovered two molecular lineages evolving independently, being one of the lineages formed by individuals from both populations. Tree-based methods (generalized mixed Yule coalescent and Bayesian implementation of the Poisson tree process) recovered similar topologies and supported single lineage recognition. Methods of molecular delimitation of species disclosed the high similarity between the two populations of Otocinclus cocama, further supported by the presence of old haplotypes common to both groups which could indicate that the populations still maintain gene flow. Although the morphological data reveal a subtle variation between both river basins, the molecular data suggest a weak population structuration based on hydrographic areas, but not different species lineages, therefore Otocinclus cocama is composed of a single lineage with two distinct morphotypes.


Assuntos
Peixes-Gato , Humanos , Animais , Peixes-Gato/genética , Rios , Código de Barras de DNA Taxonômico , Teorema de Bayes , Filogenia , Pigmentação
17.
Phys Rev Lett ; 131(16): 166702, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925706

RESUMO

Hopfions are localized and topologically nontrivial magnetic configurations that have received considerable attention in recent years. In this Letter, we use a micromagnetic approach to analyze the scattering of spin waves (SWs) by magnetic hopfions. Our results evidence that SWs experience an electromagnetic field generated by the hopfion and sharing its topological properties. In addition, SWs propagating along the hopfion symmetry axis are deflected by the magnetic texture, which acts as a convergent or divergent lens, depending on the SWs' propagation direction. Assuming that SWs propagate along the plane perpendicular to the symmetry axis, the scattering is closely related to the Aharonov-Bohm effect, allowing us to identify the magnetic hopfion as a scattering center.

18.
Chronic Stress (Thousand Oaks) ; 7: 24705470231207010, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37859939

RESUMO

Background: Social isolation (SI) and loneliness are major adult and adolescent health concerns, particularly in the coronavirus disease 2019 (COVID-19) era. Recent prospective cohort studies indicate that older women who experienced both SI and loneliness had a significantly higher risk of cardiovascular disease (CVD). Hypertension, a well-established risk factor for CVD, is more prevalent in elderly women than men. Furthermore, a lack of social relationships is strongly associated with an increased risk of hypertension in middle-aged and elderly women compared to men. Although this has not been extensively studied, adolescents and young adults who experience loneliness or SI may also be at risk for CVD and depression. The purpose of this study was to examine the effect of SI on blood pressure and depression-like behavior in young male and female mice. Methods: Weaned C57BL/6 mice were randomly assigned (n = 6/group/sex) to either group housing (GH) or SI. Animals in the SI group were housed in individual cages for 8 weeks with no view of other animals. The cages were kept in ventilated racks to prevent pheromone exposure and socially isolated animals had no cage enrichment. Results: SI increased systolic, diastolic, and mean arterial blood pressure in females and elevated heart rate in both sexes. Body weight gain was dramatically increased in socially isolated females but tended to decrease in socially isolated males. In the forced swim test, which detects depression-like behavior, there was no difference between groups in total immobility time. The latency to immobility, however, was significantly decreased in socially isolated females. Serum concentrations of corticosterone and metanephrine did not differ between socially isolated and group-housed females, but corticosterone levels were significantly reduced in socially isolated males. Conclusions: Our results indicate that 8 weeks of SI leads to significant changes in blood pressure and heart rate and mild changes in depression-like behavior in young mice, with females affected more than males.

19.
Microbiol Spectr ; 11(6): e0226023, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37787565

RESUMO

IMPORTANCE: Phosphorus (P) is the fifth most abundant element in living cells. This element is acquired mainly as inorganic phosphate (Pi, PO4 3-). In enteric bacteria, P starvation activates a two-component signal transduction system which is composed of the membrane sensor protein PhoR and its cognate transcription regulator PhoB. PhoB, in turn, promotes the transcription of genes that help maintain Pi homeostasis. Here, we characterize the P starvation response of the bacterium Salmonella enterica. We determine the PhoB-dependent and independent transcriptional changes promoted by P starvation and identify proteins enabling the utilization of a range of organic substrates as sole P sources. We show that transcription and activity of a subset of these proteins are independent of PhoB and Pi availability. These results establish that Salmonella enterica can maintain Pi homeostasis and repress PhoB/PhoR activation even when cells are grown in medium lacking Pi.


Assuntos
Proteínas de Escherichia coli , Salmonella enterica , Fósforo/metabolismo , Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Salmonella enterica/genética , Salmonella enterica/metabolismo , Organofosfatos/metabolismo , Regulação Bacteriana da Expressão Gênica , Fatores de Transcrição/metabolismo , Proteínas de Escherichia coli/genética
20.
J Fish Biol ; 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37818861

RESUMO

The present work aimed to analyze the distribution of the electrosensory pores of the Daggernose Shark Carcharhinus oxyrhynchus identifying the organ's importance in the natural history of the species. By examining photographs and digital microscope videos, we found that C. oxyrhynchus possesses the highest abundance of pores among Carcharhiniformes. This suggests a well-developed electroreceptor system, which may have maximized its evolutionary success in high turbidity environments. Furthermore, as a morphologically derived species, C. oxyrhynchus comprises a more complex and specialized electrosensory system. Notably, the species exhibits ontogenetic variation in pore abundance, highlighting the importance of a high-resolution system for adults. The higher density of pores in the ventral region indicates a preference for benthic prey, despite also feeding on pelagic items. Moreover, the species has a high-resolution electrosensory system and a high density of pores in the snout, which emphasizes the importance of the elongated snout that expands the electroreception search area coverage. Evolutionary convergence was observed in the development of the electrosensory system, as C. oxyrhynchus shares characteristics of pore distribution and abundance with phylogenetically unrelated species.

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