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1.
Nature ; 633(8030): 537-541, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39294348

RESUMO

When sustained for megayears (refs. 1,2), high-power jets from supermassive black holes (SMBHs) become the largest galaxy-made structures in the Universe3. By pumping electrons, atomic nuclei and magnetic fields into the intergalactic medium (IGM), these energetic flows affect the distribution of matter and magnetism in the cosmic web4-6 and could have a sweeping cosmological influence if they reached far at early epochs. For the past 50 years, the known size range of black hole jet pairs ended at 4.6-5.0 Mpc (refs. 7-9), or 20-30% of a cosmic void radius in the Local Universe10. An observational lack of longer jets, as well as theoretical results11, thus suggested a growth limit at about 5 Mpc (ref. 12). Here we report observations of a radio structure spanning about 7 Mpc, or roughly 66% of a coeval cosmic void radius, apparently generated by a black hole between 4.4 - 0.7 + 0.2 and 6.3 Gyr after the Big Bang. The structure consists of a northern lobe, a northern jet, a core, a southern jet with an inner hotspot and a southern outer hotspot with a backflow. This system demonstrates that jets can avoid destruction by magnetohydrodynamical instabilities over cosmological distances, even at epochs when the Universe was 7 to 1 5 - 2 + 6 times denser than it is today. How jets can retain such long-lived coherence is unknown at present.

2.
Chemosphere ; 364: 143243, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39233295

RESUMO

Phthalic acid esters (PAE) are widely used as plasticizers and have been classified as ubiquitous environmental contaminants of primary concern. PAE have accumulated intensively in surface water, groundwater, and wastewaters; thus, PAE degradation is essential. In the present study, the ability of a saline soil bacteria (SSB)-consortium to degrade synthetic wastewater-phthalates with alkyl chains of different lengths, such as diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), and di (2-ethylhexyl) phthalate (DEHP) was characterized. A central composite design-response surface methodology was applied to optimize the degradation of each phthalate, where the independent variables were temperature (21-41 °C), pH (5.3-8.6) and PAE concentration (79.5-920.4 mg L-1), and Gas Chromatography-Mass Spectrometry was used to identify the metabolites generated during phthalate degradation. Optimal conditions were 31 °C, pH 7.0, and an initial PAE concentration of 500 mg L-1, where the SSB-consortium removed 84.9%, 98.47%, 99.09% and 98.25% of initial DEP, DBP, BBP, and DEHP, respectively, in 168h. A first-order kinetic model explained - the biodegradation progression, while the half-life of PAE degradation ranged from 12.8 to 29.8 h. Genera distribution of the SSB-consortium was determined by bacterial meta-taxonomic analysis. Serratia, Methylobacillus, Acrhomobacter, and Pseudomonas were the predominant genera; however, the type of phthalate directly affected their distribution. Scanning electron microscopy analysis showed that high concentrations (1000 mg L-1) of phthalates induced morphological alterations in the bacterial SSB-consortium. The metabolite profiling showed that DEP, DBP, BBP, and DEHP could be fully metabolized through the de-esterification and ß-oxidation pathways. Therefore, the SSB-consortium can be considered a potential candidate for bioremediation of complex phthalate-contaminated water resources.


Assuntos
Biodegradação Ambiental , Ésteres , Ácidos Ftálicos , Águas Residuárias , Poluentes Químicos da Água , Ácidos Ftálicos/metabolismo , Águas Residuárias/química , Ésteres/metabolismo , Poluentes Químicos da Água/metabolismo , Bactérias/metabolismo , Microbiologia do Solo , Biocatálise , Dibutilftalato/metabolismo , Plastificantes/metabolismo , Dietilexilftalato/metabolismo
3.
Int J Mol Sci ; 25(18)2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39337365

RESUMO

Urinary tract infections (UTIs) represent a clinical and epidemiological problem of worldwide impact that affects the economy and the emotional state of the patient. Control of the condition is complicated due to multidrug resistance of pathogens associated with the disease. Considering the difficulty in carrying out effective treatment with antimicrobials, it is necessary to propose alternatives that improve the clinical status of the patients. With this purpose, in a previous study, the safety and immunostimulant capacity of a polyvalent lysate designated UNAM-HIMFG prepared with different bacteria isolated during a prospective study of chronic urinary tract infection (CUTI) was evaluated. In this work, using an animal model, results are presented on the immunostimulant and protective activity of the polyvalent UNAM-HIMFG lysate to define its potential use in the control and treatment of CUTI. Female Balb/c mice were infected through the urethra with Escherichia coli CFT073 (UPEC O6:K2:H1) strain; urine samples were collected before the infection and every week for up to 60 days. Once the animals were colonized, sublingual doses of UNAM-HIMFG lysate were administrated. The colonization of the bladder and kidneys was evaluated by culture, and their alterations were assessed using histopathological analysis. On the other hand, the immunostimulant activity of the compound was analyzed by qPCR of spleen mRNA. Uninfected animals receiving UNAM-HIMFG lysate and infected animals administered with the physiological saline solution were used as controls. During this study, the clinical status and evolution of the animals were evaluated. At ninety-six hours after infection, the presence of CFT073 was identified in the urine of infected animals, and then, sublingual administration of UNAM-HIMFG lysate was started every week for 60 days. The urine culture of mice treated with UNAM-HIMFG lysate showed the presence of bacteria for three weeks post-treatment; in contrast, in the untreated animals, positive cultures were observed until the 60th day of this study. The histological analysis of bladder samples from untreated animals showed the presence of chronic inflammation and bacteria in the submucosa, while tissues from mice treated with UNAM-HIMFG lysate did not show alterations. The same analysis of kidney samples of the two groups (treated and untreated) did not present alterations. Immunostimulant activity assays of UNAM-HIMFG lysate showed overexpression of TNF-α and IL-10. Results suggest that the lysate activates the expression of cytokines that inhibit the growth of inoculated bacteria and control the inflammation responsible for tissue damage. In conclusion, UNAM-HIMFG lysate is effective for the treatment and control of CUTIs without the use of antimicrobials.


Assuntos
Infecções por Escherichia coli , Camundongos Endogâmicos BALB C , Bexiga Urinária , Infecções Urinárias , Escherichia coli Uropatogênica , Animais , Infecções Urinárias/microbiologia , Infecções Urinárias/imunologia , Feminino , Camundongos , Bexiga Urinária/microbiologia , Bexiga Urinária/imunologia , Bexiga Urinária/patologia , Bexiga Urinária/efeitos dos fármacos , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Escherichia coli Uropatogênica/imunologia , Escherichia coli Uropatogênica/patogenicidade , Modelos Animais de Doenças , Adjuvantes Imunológicos/farmacologia , Lisados Bacterianos
4.
Res Sq ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39257983

RESUMO

The vast majority of gene mutations and/or gene knockouts result in either no observable changes, or significant deficits in molecular, cellular, or organismal function. However, in a small number of cases, mutant animal models display enhancements in specific behaviors such as learning and memory. To date, most gene deletions shown to enhance cognitive ability generally affect a limited number of pathways such as NMDA receptor- and translation-dependent plasticity, or GABA receptor- and potassium channel-mediated inhibition. While endolysosomal trafficking of AMPA receptors is a critical mediator of synaptic plasticity, mutations in genes that affect AMPAR trafficking either have no effect or are deleterious for synaptic plasticity, learning and memory. NSG2 is one of the three-member family of Neuron-specific genes (NSG1-3), which have been shown to regulate endolysosomal trafficking of a number of proteins critical for neuronal function, including AMPAR subunits (GluA1-2). Based on these findings and the largely universal expression throughout mammalian brain, we predicted that genetic knockout of NSG2 would result in significant impairments across multiple behavioral modalities including motor, affective, and learning/memory paradigms. However, in the current study we show that loss of NSG2 had highly selective effects on associative learning and memory, leaving motor and affective behaviors intact. For instance, NSG2 KO animals performed equivalent to wild-type C57Bl/6n mice on rotarod and Catwalk motor tasks, and did not display alterations in anxiety-like behavior on open field and elevated zero maze tasks. However, NSG2 KO animals demonstrated enhanced recall in the Morris water maze, accelerated reversal learning in a touch-screen task, and accelerated acquisition and enhanced recall on a Trace Fear Conditioning task. Together, these data point to a specific involvement of NSG2 on multiple types of associative learning, and expand the repertoire of pathways that can be targeted for cognitive enhancement.

5.
AIDS Behav ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287733

RESUMO

The goal of HIV cure research is to either eliminate HIV from the body or durably suppress it in the absence of antiretroviral therapy (ART). This research often requires participants to interrupt ART. However, there are numerous risks associated with ART interruptions and therefore it is critical to understand how people with HIV (PWH) who participate recall the elements of consent, to safeguard their rights and welfare. Participants were recruited from the SCOPE Analytic Treatment Interruption (SCOPE-ATI: NCT04359186) study at the University of California San Francisco. We interviewed 12 SCOPE-ATI participants to assess their recall of informed consent elements and therapeutic misconception, using the Brief Informed Consent Evaluation Protocol (BICEP). Interviewees were primarily older adults, male, White, and non-Hispanic/Latinx. Their responses indicated that they understood the primary purpose of the SCOPE-ATI study to be scientific research. Nearly all participants demonstrated high recall of key elements of consent and no therapeutic misconception. We also found that the role of study staff was a major factor in participants' appraisal of risks and that associated psychosocial risks of pausing ART were of minimal concern (e.g., anxiety off ART, possible forward HIV transmission to sex partners). As HIV cure research expands, it is important to reiterate the duty of the investigative team to clearly communicate with participants about the associated risks and to assess their understanding throughout these studies.

6.
Sci Transl Med ; 16(754): eadk3295, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959327

RESUMO

The mechanisms of postacute medical conditions and unexplained symptoms after SARS-CoV-2 infection [Long Covid (LC)] are incompletely understood. There is growing evidence that viral persistence, immune dysregulation, and T cell dysfunction may play major roles. We performed whole-body positron emission tomography imaging in a well-characterized cohort of 24 participants at time points ranging from 27 to 910 days after acute SARS-CoV-2 infection using the radiopharmaceutical agent [18F]F-AraG, a selective tracer that allows for anatomical quantitation of activated T lymphocytes. Tracer uptake in the postacute COVID-19 group, which included those with and without continuing symptoms, was higher compared with prepandemic controls in many regions, including the brain stem, spinal cord, bone marrow, nasopharyngeal and hilar lymphoid tissue, cardiopulmonary tissues, and gut wall. T cell activation in the spinal cord and gut wall was associated with the presence of LC symptoms. In addition, tracer uptake in lung tissue was higher in those with persistent pulmonary symptoms specifically. Increased T cell activation in these tissues was also observed in many individuals without LC. Given the high [18F]F-AraG uptake detected in the gut, we obtained colorectal tissue for in situ hybridization of SARS-CoV-2 RNA and immunohistochemical studies in a subset of five participants with LC symptoms. We identified intracellular SARS-CoV-2 single-stranded spike protein-encoding RNA in rectosigmoid lamina propria tissue in all five participants and double-stranded spike protein-encoding RNA in three participants up to 676 days after initial COVID-19, suggesting that tissue viral persistence could be associated with long-term immunologic perturbations.


Assuntos
COVID-19 , Ativação Linfocitária , Tomografia por Emissão de Pósitrons , RNA Viral , SARS-CoV-2 , Linfócitos T , Humanos , COVID-19/imunologia , COVID-19/virologia , COVID-19/patologia , Linfócitos T/imunologia , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Idoso , Pulmão/virologia , Pulmão/patologia , Pulmão/diagnóstico por imagem , Fatores de Tempo
7.
Toxicol Res (Camb) ; 13(4): tfae103, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39006882

RESUMO

Background: Phthalates are additives used as plasticizers among other uses, classified as endocrine disruptors and may contribute to some metabolic disorders. The aim of this work was to determine the effect of the exposure of diethyl phthalate (DEP) and dibutyl phthalate (DBP) on cell viability and reactive oxygen species (ROS) production, as well as the regulation of sirloins in HepG2 cells. Methods: HepG2 cells were exposed to DEP or DBP at 0.1, 1, 10 and 100 µg/mL, and after 48 or 72 h the gene and protein expression of sirtuins was quantified by qRT-PCR and Western-Blot, respectively. Results: Results showed that even at a low concentration of 0.1 µg/mL DEP affected the expression of Sirt3 and Sirt4, whereas DBP at 0.1 µg/mL affected Sirt3 and Sirt5 gene expression. Protein analysis showed a reduction in Sirt1 levels at a DEP concentration of 1 µg/mL and higher, while DBP at higher dose (100 µg/mL) decreased Sirt3 protein levels. Cell viability decreased by 20% only at higher dose (100 µg/mL) and ROS production increased at 10 and 100 µg/mL for both phthalates. Conclusion: These findings indicate that exposure to low concentrations (0.1 µg/mL) of DEP or DBP can negatively influence the expression of some sirtuins.

8.
Zoonoses Public Health ; 71(6): 755-762, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38982628

RESUMO

AIMS: Campylobacteriosis, caused by Campylobacter spp., is one of the most important foodborne zoonotic diseases in the world and a common cause of gastroenteritis. In the European Union, campylobacteriosis is considered the most common zoonotic disease, with over 10,000 cases in 2020 alone. This high occurrence highlights the need of more efficient surveillance methods and identification of key points. METHODS AND RESULTS: Herein, we evaluated and identified key points of Campylobacter spp. occurrence along the Spanish food chain during 2015-2020, based on the following variables: product, stage and region. We analysed a dataset provided by the Spanish Agency for Food Safety and Nutrition using a machine learning algorithm (random forests). Campylobacter presence was influenced by the three selected explanatory variables, especially by product, followed by region and stage. Among the studied products, meat, especially poultry and sheep, presented the highest probability of occurrence of Campylobacter, where the bacterium was present in the initial, intermediate and final stages (e.g., wholesale, retail) of the food chain. The presence in final stages may represent direct consumer exposure to the bacteria. CONCLUSSIONS: By using the random forest method, this study contributes to the identification of Campylobacter key points and the evaluation of control efforts in the Spanish food chain.


Assuntos
Infecções por Campylobacter , Campylobacter , Microbiologia de Alimentos , Campylobacter/isolamento & purificação , Espanha/epidemiologia , Animais , Infecções por Campylobacter/epidemiologia , Humanos , Cadeia Alimentar , Carne/microbiologia , Zoonoses
9.
Ecol Evol ; 14(6): e11456, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895569

RESUMO

The decline of honey bee populations significantly impacts the human food supply due to poor pollination and yield decreases of essential crop species. Given the reduction of pollinators, research into critical landscape components, such as floral resource availability and land use change, might provide valuable information about the nutritional status and health of honey bee colonies. To address this issue, we examine the effects of landscape factors like agricultural area, urban area, and climatic factors, including maximum temperature, minimum temperature, relative humidity, and precipitation, on honey bee hive populations and nutritional health of 326 honey bee colonies across varying landscapes in Mexico. DNA metabarcoding facilitated the precise identification of pollen from 267 plant species, encompassing 243 genera and 80 families, revealing a primary herb-based diet. Areas characterized by high landscape diversity exhibited greater pollen diversity within the colony. Conversely, colonies situated in regions with higher proportions of agricultural and urban landscapes demonstrated lower bee density. The maximum ambient temperature outside hives positively correlated with pollen diversity, aligning with a simultaneous decrease in bee density. Conversely, higher relative humidity positively influenced both the bee density of the colony and the diversity of foraged pollen. Our national-level study investigated pollen dietary availability and colony size in different habitat types, latitudes, climatic conditions, and varied levels and types of disturbances. This effort was taken to gain a better insight into the mechanisms driving declines in honey bee populations. This study illustrates the need for more biodiverse agricultural landscapes, the preservation of diverse habitats, and the conservation of natural and semi-natural spaces. These measures can help to improve the habitat quality of other bee species, as well as restore essential ecosystem processes, such as pollination and pest control.

10.
Int J Mol Sci ; 25(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38928005

RESUMO

The pregnane X receptor (PXR) is a nuclear hormone receptor that plays a pivotal role in regulating gene expression in response to various ligands, particularly xenobiotics. In this context, the aim of this study was to shed light on the ligand affinity and functions of four NR1J1 paralogs identified in the marine mussel Mytilus galloprovincialis, employing a dual-luciferase reporter assay. To achieve this, the activation patterns of these paralogs in response to various toxins, including freshwater cyanotoxins (Anatoxin-a, Cylindrospermopsin, and Microcystin-LR, -RR, and -YR) and marine algal toxins (Nodularin, Saxitoxin, and Tetrodotoxin), alongside natural compounds (Saint John's Wort, Ursolic Acid, and 8-Methoxypsoralene) and microalgal extracts (Tetraselmis, Isochrysis, LEGE 95046, and LEGE 91351 extracts), were studied. The investigation revealed nuanced differences in paralog response patterns, highlighting the remarkable sensitivity of MgaNR1J1γ and MgaNR1J1δ paralogs to several toxins. In conclusion, this study sheds light on the intricate mechanisms of xenobiotic metabolism and detoxification, particularly focusing on the role of marine mussel NR1J1 in responding to a diverse array of compounds. Furthermore, comparative analysis with human PXR revealed potential species-specific adaptations in detoxification mechanisms, suggesting evolutionary implications. These findings deepen our understanding of PXR-mediated metabolism mechanisms, offering insights into environmental monitoring and evolutionary biology research.


Assuntos
Toxinas Marinhas , Mytilus , Receptor de Pregnano X , Animais , Receptor de Pregnano X/metabolismo , Receptor de Pregnano X/genética , Mytilus/metabolismo , Mytilus/genética , Humanos , Microcistinas/metabolismo , Microalgas/metabolismo , Microalgas/genética , Xenobióticos/metabolismo , Toxinas Bacterianas/metabolismo , Toxinas de Cianobactérias
11.
Front Glob Womens Health ; 5: 1339821, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38847001

RESUMO

Introduction: Vaginal Candida colonization (CC) can lead to vulvovaginal candidiasis, the second most prevalent vaginal condition worldwide, and has been associated with adverse birth outcomes. However, no data on CC in the Democratic Republic of the Congo are available. We investigated the prevalence, Candida species, clinical correlates, risk factors and pregnancy outcomes in women with CC in the second trimester of pregnancy. Material and methods: In Bukavu, the Democratic Republic of the Congo, pregnant women were recruited during antenatal care between 16 and 20 weeks of gestation from January 2017 to October 2017 and followed until delivery. Sociodemographics, sexual behavioral, hygienic and clinical characteristics, microbiological data and pregnancy outcomes were collected. Candida detection and speciation was performed with microscopy (Gram-stained smears and wet-mount) and/or quantitative PCR. Multivariate regression models were used to estimate the different associations with CC. Results: The prevalence of CC by wet mount, microscopy of Gram-stain smears and qPCR was 27.9%, 28.1% and 38.2%, respectively. C. albicans was the most prevalent Candida species (91.0%). Previous genital infections, an intermediate vaginal microbiota, bacterial vaginosis, and the use of pit toilets were risk factors for CC. Clinically, CC was associated with itching only. Women with CC had twice the odds for preterm birth, if Candida concentration was high, the odds were four times higher. Conclusions: In Bukavu, the Democratic Republic of the Congo, the prevalence of CC was high and associated with microbiological and modifiable risk factors. Screening and treatment for CC during antenatal care should be investigated as a possible strategy to reduce preterm birth.

13.
Front Med (Lausanne) ; 11: 1355803, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737760

RESUMO

Background: Ankylosing spondylitis (AS) is a chronic, inflammatory, and autoimmune disease. This condition primarily affects the axial skeleton and presents direct foot involvement, such as Achilles enthesitis or plantar fascia involvement. Objective: This study aimed to investigate the impact of foot health on the quality of life of individuals with AS compared to a control group without AS. Materials and methods: A sample of 112 subjects was recruited, with a mean age of 46.80 ± 10.49 years, divided into two groups: 56 individuals with AS (cases) and 56 individuals without AS (controls). Demographic data were collected, and the scores obtained in the Foot Health Status Questionnaire domains were recorded. Results: Of the participants, 27.79% (N = 30) were men and 73.21% (N = 82) were women. The mean age in the group was 46.80 ± 10.49. Significant differences (p < 0.05) were found in the domains of foot function, foot pain, footwear, overall foot health, general health-related physical activity, and social capacity between the AS group and the control group. Conclusion: Individuals with AS exhibited a decreased quality of life, as indicated by their Foot Health Status Questionnaire scores.

14.
ACS Omega ; 9(17): 18862-18871, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38708243

RESUMO

Chipilin (Crotalaria longirostrata) is consumed as a vegetable in the preparation of traditional dishes. As a folk medicine, Chipilin extracts are used as a hypnotic and sedative agent; however, there are few reports that support these uses. This study aimed to characterize the compounds present in Chipilin leaf extracts and to investigate their sedative effect using zebrafish as an in vivo model. Extracts were obtained by maceration with water (H2O), ethanol (EtOH), and EtOH-H2O, while oleoresin was obtained by supercritical fluid extraction (SFE). Total phenolic and flavonoid contents were quantified by colorimetric methods. Phytochemical constituents were identified by gas chromatography-mass spectrometry (GC-MS) analysis. The chronic and acute toxicities of Chipilin extracts were tested in zebrafish embryos and larvae, respectively. Chipilin sedative effect was tested by the larvae response to dark-light-dark transitions. EtOH-H2O extracts had the highest value of total phenolics (5345 ± 5.1 µg GAE/g), followed by water and oleoresin (1815 ± 5.1 and 394 ± 5.1 µg GAE/g, respectively). In water extracts were identified the alkaloid trachelanthamidine, 1,2ß-epoxy- and the alkyl ketone 7,9-di-tert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione, while oleamide, α-monostearin, and erucamide were detected in all samples except in water extracts. Oleoresin extract had the lowest embryotoxicity (LC50 = 4.99 µg/mL) and the highest sedative effects. SFE is a green alternative to obtain Chipilin extracts rich in erucamide, an endocannabinoid analogue, which plays an important role in the development of the central nervous system and in modulating neurotransmitter release.

15.
Mol Ecol ; 33(13): e17424, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38813851

RESUMO

Climate change and land use change are two main drivers of global biodiversity decline, decreasing the genetic diversity that populations harbour and altering patterns of local adaptation. Landscape genomics allows measuring the effect of these anthropogenic disturbances on the adaptation of populations. However, both factors have rarely been considered simultaneously. Based on a set of 3660 SNPs from which 130 were identified as outliers by a genome-environment association analysis (LFMM), we modelled the spatial turnover of allele frequencies in 19 localities of Pinus leiophylla across the Avocado Belt in Michoacán state, Mexico. Then, we evaluated the effect of climate change and land use change scenarios, in addition to evaluating assisted gene flow strategies and connectivity metrics across the landscape to identify priority conservation areas for the species. We found that localities in the centre-east of the Avocado Belt would be more vulnerable to climate change, while localities in the western area are more threatened by land conversion to avocado orchards. Assisted gene flow actions could aid in mitigating both threats. Connectivity patterns among forest patches will also be modified by future habitat loss, with central and eastern parts of the Avocado Belt maintaining the highest connectivity. These results suggest that areas with the highest priority for conservation are in the eastern part of the Avocado Belt, including the Monarch Butterfly Biosphere Reserve. This work is useful as a framework that incorporates distinct layers of information to provide a more robust representation of the response of tree populations to anthropogenic disturbances.


Assuntos
Mudança Climática , Fluxo Gênico , Persea , Pinus , Polimorfismo de Nucleotídeo Único , Pinus/genética , Persea/genética , México , Frequência do Gene , Adaptação Fisiológica/genética , Genética Populacional , Conservação dos Recursos Naturais , Ecossistema , Variação Genética
16.
J Parkinsons Dis ; 14(4): 797-808, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38701160

RESUMO

Background: Video-oculography constitutes a highly-sensitive method of characterizing ocular movements, which could detect subtle premotor changes and contribute to the early diagnosis of Parkinson's disease (PD). Objective: To investigate potential oculomotor differences between idiopathic PD (iPD) and PD associated with the G2019S variant of LRRK2 (L2PD), as well as to evaluate oculomotor function in asymptomatic carriers of the G2019S variant of LRRK2. Methods: The study enrolled 129 subjects: 30 PD (16 iPD, 14 L2PD), 23 asymptomatic carriers, 13 non-carrier relatives of L2PD patients, and 63 unrelated HCs. The video-oculographic evaluation included fixation, prosaccade, antisaccade, and memory saccade tests. Results: We did not find significant differences between iPD and L2PD. Compared to controls, PD patients displayed widespread oculomotor deficits including larger microsaccades, hypometric vertical prosaccades, increased latencies in all tests, and lower percentages of successful antisaccades and memory saccades. Non-carrier relatives showed oculomotor changes with parkinsonian features, such as fixation instability and hypometric vertical saccades. Asymptomatic carriers shared multiple similarities with PD, including signs of unstable fixation and hypometric vertical prosaccades; however, they were able to reach percentages of successful antisaccade and memory saccades similar to controls, although at the expense of longer latencies. Classification accuracy of significant oculomotor parameters to differentiate asymptomatic carriers from HCs ranged from 0.68 to 0.74, with BCEA, a marker of global fixation instability, being the parameter with the greatest classification accuracy. Conclusions: iPD and LRRK2-G2019S PD patients do not seem to display a differential oculomotor profile. Several oculomotor changes in asymptomatic carriers of LRRK2 mutations could be considered premotor biomarkers.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Doença de Parkinson , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Doença de Parkinson/fisiopatologia , Doença de Parkinson/genética , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Transtornos da Motilidade Ocular/etiologia , Transtornos da Motilidade Ocular/fisiopatologia , Transtornos da Motilidade Ocular/genética , Transtornos da Motilidade Ocular/diagnóstico , Movimentos Sacádicos/fisiologia , Heterozigoto , Adulto
18.
J Vet Diagn Invest ; 36(4): 522-528, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38653733

RESUMO

Rabies virus (RABV; Lyssavirus rabies) is a neurotropic virus that can be transmitted to mammals by the hematophagous bat Desmodus rotundus. An accurate, accessible method for the detection of RABV in cattle is necessary in Paraguay; thus, we evaluated the detection of RABV using 4 techniques: fluorescent antibody test (FAT), immunochromatography rapid detection test (RDT; Anigen Rapid Rabies Ag test kit; Bionote), a reverse-transcription PCR (RT-PCR) assay, and histologic lesions in different portions of the CNS of 49 Paraguayan cattle to determine the most sensitive and specific technique. By FAT and RDT, 15 of 49 (31%) samples were positive. By RT-PCR amplification of N and G genes, 13 of 49 (27%) and 12 of 49 (25%) were positive, respectively. RDT had high agreement with FAT (kappa = 1); sensitivity was 100% (95% CI: 97-100%) and specificity was 100% (95% CI: 99-100%). The amplification of the N and G genes resulted in substantial agreement (kappa of 0.9 and 0.8, respectively) compared with FAT, and the sensitivity and specificity of the N gene were 87% (95% CI: 66-100%) and 100% (95% CI: 98-100%), respectively, and those of the G gene were 80% (95% CI: 56-100%) and 100% (95% CI: 98-100%), respectively. Histologic lesions observed were lymphoplasmacytic meningoencephalitis, gliosis, and neuronophagia. The agreement observed between the FAT and RDT tests suggests that RDT is an accurate tool for the detection of RABV. Histopathology can be used to confirm lesions caused by RABV and to rule out other conditions; the RT-PCR assay is useful for molecular epidemiology studies.


Assuntos
Doenças dos Bovinos , Vírus da Raiva , Raiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Animais , Raiva/veterinária , Raiva/diagnóstico , Raiva/virologia , Bovinos , Paraguai , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/genética , Doenças dos Bovinos/virologia , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Imunofluorescência/veterinária
19.
Ann Bot ; 133(7): 1007-1024, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38428030

RESUMO

BACKGROUND AND AIMS: Introgressive hybridization poses a challenge to taxonomic and phylogenetic understanding of taxa, particularly when there are high numbers of co-occurring, intercrossable species. The genus Quercus exemplifies this situation. Oaks are highly diverse in sympatry and cross freely, creating syngameons of interfertile species. Although a well-resolved, dated phylogeny is available for the American oak clade, evolutionary relationships within many of the more recently derived clades remain to be defined, particularly for the young and exceptionally diverse Mexican white oak clade. Here, we adopted an approach bridging micro- and macroevolutionary scales to resolve evolutionary relationships in a rapidly diversifying clade endemic to Mexico. METHODS: Ecological data and sequences of 155 low-copy nuclear genes were used to identify distinct lineages within the Quercus laeta complex. Concatenated and coalescent approaches were used to assess the phylogenetic placement of these lineages relative to the Mexican white oak clade. Phylogenetic network methods were applied to evaluate the timing and genomic significance of recent or historical introgression among lineages. KEY RESULTS: The Q. laeta complex comprises six well-supported lineages, each restricted geographically and with mostly divergent climatic niches. Species trees corroborated that the different lineages are more closely related to other species of Mexican white oaks than to each other, suggesting that this complex is polyphyletic. Phylogenetic networks estimated events of ancient introgression that involved the ancestors of three present-day Q. laeta lineages. CONCLUSIONS: The Q. laeta complex is a morphologically and ecologically related group of species rather than a clade. Currently, oak phylogenetics is at a turning point, at which it is necessary to integrate phylogenetics and ecology in broad regional samples to figure out species boundaries. Our study illuminates one of the more complicated of the Mexican white oak groups and lays groundwork for further taxonomic study.


Assuntos
Filogenia , Quercus , Hibridização Genética , México , Quercus/genética
20.
Ecol Evol ; 14(3): e11178, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38505177

RESUMO

Genetic diversity is a key component of evolution, and unraveling factors that promote genetic differentiation in space and time is a central question in evolutionary biology. One of the most diverse and ecologically important tree genera in tropical forests worldwide is Ficus (Moraceae). It has been suggested that, given the great dispersal capacity of pollinating fig wasps (Chalcidoidea; Agaonidae), the spatial genetic structure, particularly in monoecious fig species, should be weak. However, no studies have addressed the factors that determine the genetic structure of Ficus species in regions of high geological, geographic, and climatic complexity, such as the Mexican Transition Zone. Using nuclear single nucleotide polymorphisms (5311 SNPs) derived from low-coverage whole genomes and 17 populations, we analyzed the population genomics of Ficus pringlei to characterize neutral and adaptive genetic variation and structure and its association with geographic barriers such as the Trans-Mexican Volcanic Belt, environmental heterogeneity, and wind connectivity. From genomic data of 71 individuals, high genetic diversity, and the identification of three genomic lineages were recorded (North, South, and Churumuco). The results suggest that genetic variation is primarily determined by climatic heterogeneity. Ficus pringlei populations from the north and south of the Trans-Mexican Volcanic Belt also exhibited minimal genetic differentiation (F ST = 0.021), indicating that this mountain range may not act as an insurmountable barrier to gene flow. Wind connectivity is also highlighted in structuring putative adaptive genetic variation, underscoring the intricate complexity of the various factors influencing genetic variation in the species. This study provides information on the possible mechanisms underlying the genetic variation of endemic species of the tropical dry forest of Western Mexico, such as F. pringlei.

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