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1.
N Engl J Med ; 388(17): 1582-1596, 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37099341

RESUMO

BACKGROUND: The bacille Calmette-Guérin (BCG) vaccine has immunomodulatory "off-target" effects that have been hypothesized to protect against coronavirus disease 2019 (Covid-19). METHODS: In this international, double-blind, placebo-controlled trial, we randomly assigned health care workers to receive the BCG-Denmark vaccine or saline placebo and followed them for 12 months. Symptomatic Covid-19 and severe Covid-19, the primary outcomes, were assessed at 6 months; the primary analyses involved the modified intention-to-treat population, which was restricted to participants with a negative test for severe acute respiratory syndrome coronavirus 2 at baseline. RESULTS: A total of 3988 participants underwent randomization; recruitment ceased before the planned sample size was reached owing to the availability of Covid-19 vaccines. The modified intention-to-treat population included 84.9% of the participants who underwent randomization: 1703 in the BCG group and 1683 in the placebo group. The estimated risk of symptomatic Covid-19 by 6 months was 14.7% in the BCG group and 12.3% in the placebo group (risk difference, 2.4 percentage points; 95% confidence interval [CI], -0.7 to 5.5; P = 0.13). The risk of severe Covid-19 by 6 months was 7.6% in the BCG group and 6.5% in the placebo group (risk difference, 1.1 percentage points; 95% CI, -1.2 to 3.5; P = 0.34); the majority of participants who met the trial definition of severe Covid-19 were not hospitalized but were unable to work for at least 3 consecutive days. In supplementary and sensitivity analyses that used less conservative censoring rules, the risk differences were similar but the confidence intervals were narrower. There were five hospitalizations due to Covid-19 in each group (including one death in the placebo group). The hazard ratio for any Covid-19 episode in the BCG group as compared with the placebo group was 1.23 (95% CI, 0.96 to 1.59). No safety concerns were identified. CONCLUSIONS: Vaccination with BCG-Denmark did not result in a lower risk of Covid-19 among health care workers than placebo. (Funded by the Bill and Melinda Gates Foundation and others; BRACE ClinicalTrials.gov number, NCT04327206.).


Assuntos
Adjuvantes Imunológicos , Vacina BCG , COVID-19 , Pessoal de Saúde , Humanos , Vacina BCG/uso terapêutico , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/uso terapêutico , Método Duplo-Cego , SARS-CoV-2 , Adjuvantes Imunológicos/uso terapêutico
2.
Proc Natl Acad Sci U S A ; 120(52): e2300842120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38127979

RESUMO

Normal and pathologic neurobiological processes influence brain morphology in coordinated ways that give rise to patterns of structural covariance (PSC) across brain regions and individuals during brain aging and diseases. The genetic underpinnings of these patterns remain largely unknown. We apply a stochastic multivariate factorization method to a diverse population of 50,699 individuals (12 studies and 130 sites) and derive data-driven, multi-scale PSCs of regional brain size. PSCs were significantly correlated with 915 genomic loci in the discovery set, 617 of which are newly identified, and 72% were independently replicated. Key pathways influencing PSCs involve reelin signaling, apoptosis, neurogenesis, and appendage development, while pathways of breast cancer indicate potential interplays between brain metastasis and PSCs associated with neurodegeneration and dementia. Using support vector machines, multi-scale PSCs effectively derive imaging signatures of several brain diseases. Our results elucidate genetic and biological underpinnings that influence structural covariance patterns in the human brain.


Assuntos
Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/patologia , Mapeamento Encefálico/métodos , Genômica , Neoplasias Encefálicas/patologia
3.
PLoS Pathog ; 19(2): e1011154, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36780566

RESUMO

Type IV pilus (TFP) is a multifunctional bacterial structure involved in twitching motility, adhesion, biofilm formation, as well as natural competence. Here, by site-directed mutagenesis and functional analysis, we determined the phenotype conferred by each of the 38 genes known to be required for TFP biosynthesis and regulation in the reemergent plant pathogenic fastidious prokaryote Xylella fastidiosa. This pathogen infects > 650 plant species and causes devastating diseases worldwide in olives, grapes, blueberries, and almonds, among others. This xylem-limited, insect-transmitted pathogen lives constantly under flow conditions and therefore is highly dependent on TFP for host colonization. In addition, TFP-mediated natural transformation is a process that impacts genomic diversity and environmental fitness. Phenotypic characterization of the mutants showed that ten genes were essential for both movement and natural competence. Interestingly, seven sets of paralogs exist, and mutations showed opposing phenotypes, indicating evolutionary neofunctionalization of subunits within TFP. The minor pilin FimT3 was the only protein exclusively required for natural competence. By combining approaches of molecular microbiology, structural biology, and biochemistry, we determined that the minor pilin FimT3 (but not the other two FimT paralogs) is the DNA receptor in TFP of X. fastidiosa and constitutes an example of neofunctionalization. FimT3 is conserved among X. fastidiosa strains and binds DNA non-specifically via an electropositive surface identified by homolog modeling. This protein surface includes two arginine residues that were exchanged with alanine and shown to be involved in DNA binding. Among plant pathogens, fimT3 was found in ~ 10% of the available genomes of the plant associated Xanthomonadaceae family, which are yet to be assessed for natural competence (besides X. fastidiosa). Overall, we highlight here the complex regulation of TFP in X. fastidiosa, providing a blueprint to understand TFP in other bacteria living under flow conditions.


Assuntos
Proteínas de Fímbrias , Fímbrias Bacterianas , Proteínas de Fímbrias/metabolismo , Fímbrias Bacterianas/metabolismo , Movimento , Mutação , Doenças das Plantas/microbiologia
4.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983846

RESUMO

Many soil-, water-, and plant-associated bacterial species from the orders Xanthomonadales, Burkholderales, and Neisseriales carry a type IV secretion system (T4SS) specialized in translocating effector proteins into other gram-negative species, leading to target cell death. These effectors, known as X-Tfes, carry a carboxyl-terminal domain of ∼120 residues, termed XVIPCD, characterized by several conserved motifs and a glutamine-rich tail. Previous studies showed that the XVIPCD is required for interaction with the T4SS coupling protein VirD4 and for T4SS-dependent translocation. However, the structural basis of the XVIPCD-VirD4 interaction is unknown. Here, we show that the XVIPCD interacts with the central all-alpha domain of VirD4 (VirD4AAD). We used solution NMR spectroscopy to solve the structure of the XVIPCD of X-TfeXAC2609 from Xanthomonas citri and to map its interaction surface with VirD4AAD Isothermal titration calorimetry and in vivo Xanthomonas citri versus Escherichia coli competition assays using wild-type and mutant X-TfeXAC2609 and X-TfeXAC3634 indicate that XVIPCDs can be divided into two regions with distinct functions: the well-folded N-terminal region contains specific conserved motifs that are responsible for interactions with VirD4AAD, while both N- and carboxyl-terminal regions are required for effective X-Tfe translocation into the target cell. The conformational stability of the N-terminal region is reduced at and below pH 7.0, a property that may facilitate X-Tfe unfolding and translocation through the more acidic environment of the periplasm.


Assuntos
Antibacterianos/química , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Escherichia coli/química , Sistemas de Secreção Tipo IV/antagonistas & inibidores , Sistemas de Secreção Tipo IV/química , Xanthomonas/química , Proteínas de Bactérias/genética , Escherichia coli/genética , Modelos Moleculares , Mutação , Ressonância Magnética Nuclear Biomolecular , Domínios Proteicos , Relação Estrutura-Atividade , Sistemas de Secreção Tipo IV/genética , Xanthomonas/genética
5.
PLoS Med ; 21(1): e1004255, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38194420

RESUMO

BACKGROUND: Malaria transmission modelling has demonstrated the potential impact of semiquantitative glucose-6-phosphate dehydrogenase (G6PD) testing and treatment with single-dose tafenoquine for Plasmodium vivax radical cure but has not investigated the associated costs. This study evaluated the cost-effectiveness of P. vivax treatment with tafenoquine after G6PD testing using a transmission model. METHODS AND FINDINGS: We explored the cost-effectiveness of using tafenoquine after G6PD screening as compared to usual practice (7-day low-dose primaquine (0.5 mg/kg/day) without G6PD screening) in Brazil using a 10-year time horizon with 5% discounting considering 4 scenarios: (1) tafenoquine for adults only assuming 66.7% primaquine treatment adherence; (2) tafenoquine for adults and children aged >2 years assuming 66.7% primaquine adherence; (3) tafenoquine for adults only assuming 90% primaquine adherence; and (4) tafenoquine for adults only assuming 30% primaquine adherence. The incremental cost-effectiveness ratios (ICERs) were estimated by dividing the incremental costs by the disability-adjusted life years (DALYs) averted. These were compared to a willingness to pay (WTP) threshold of US$7,800 for Brazil, and one-way and probabilistic sensitivity analyses were performed. All 4 scenarios were cost-effective in the base case analysis using this WTP threshold with ICERs ranging from US$154 to US$1,836. One-way sensitivity analyses showed that the results were most sensitive to severity and mortality due to vivax malaria, the lifetime and number of semiquantitative G6PD analysers needed, cost per malaria episode and per G6PD test strips, and life expectancy. All scenarios had a 100% likelihood of being cost-effective at the WTP threshold. The main limitations of this study are due to parameter uncertainty around our cost estimates for low transmission settings, the costs of G6PD screening, and the severity of vivax malaria. CONCLUSIONS: In our modelling study that incorporated impact on transmission, tafenoquine prescribed after a semiquantitative G6PD testing was highly likely to be cost-effective in Brazil. These results demonstrate the potential health and economic importance of ensuring safe and effective radical cure.


Assuntos
Malária Vivax , Primaquina , Adulto , Criança , Humanos , Primaquina/efeitos adversos , Malária Vivax/diagnóstico , Malária Vivax/tratamento farmacológico , Brasil , Análise de Custo-Efetividade , Glucosefosfato Desidrogenase
6.
BMC Cancer ; 24(1): 346, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38500100

RESUMO

BACKGROUND: The androgen/androgen receptor (AR)-signaling axis plays a central role in prostate cancer (PCa). Upon androgen-binding the AR dimerizes with another AR, and translocates into the nucleus where the AR-dimer activates/inactivates androgen-dependent genes. Consequently, treatments for PCa are commonly based on androgen deprivation therapy (ADT). The clinical benefits of ADT are only transitory and most tumors develop mechanisms allowing the AR to bypass its need for physiological levels of circulating androgens. Clinical failure of ADT is often characterized by the synthesis of a constitutively active AR splice variant, termed AR-V7. AR-V7 mRNA expression is considered as a resistance mechanism following ADT. AR-V7 no longer needs androgenic stimuli for nuclear entry and/or dimerization. METHODS: Our goal was to mechanistically decipher the interaction between full-length AR (AR-FL) and AR-V7 in AR-null HEK-293 cells using the NanoLuc Binary Technology under androgen stimulation and deprivation conditions. RESULTS: Our data point toward a hypothesis that AR-FL/AR-FL homodimers form in the cytoplasm, whereas AR-V7/AR-V7 homodimers localize in the nucleus. However, after androgen stimulation, all the AR-FL/AR-FL, AR-FL/AR-V7 and AR-V7/AR-V7 dimers were localized in the nucleus. CONCLUSIONS: We showed that AR-FL and AR-V7 form heterodimers that localize to the nucleus, whereas AR-V7/AR-V7 dimers were found to localize in the absence of androgens in the nucleus.


Assuntos
Luciferases , Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Androgênios , Neoplasias da Próstata/patologia , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Células HEK293 , Neoplasias de Próstata Resistentes à Castração/patologia , Isoformas de Proteínas/genética
7.
Mol Psychiatry ; 28(5): 2008-2017, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147389

RESUMO

Using machine learning, we recently decomposed the neuroanatomical heterogeneity of established schizophrenia to discover two volumetric subgroups-a 'lower brain volume' subgroup (SG1) and an 'higher striatal volume' subgroup (SG2) with otherwise normal brain structure. In this study, we investigated whether the MRI signatures of these subgroups were also already present at the time of the first-episode of psychosis (FEP) and whether they were related to clinical presentation and clinical remission over 1-, 3-, and 5-years. We included 572 FEP and 424 healthy controls (HC) from 4 sites (Sao Paulo, Santander, London, Melbourne) of the PHENOM consortium. Our prior MRI subgrouping models (671 participants; USA, Germany, and China) were applied to both FEP and HC. Participants were assigned into 1 of 4 categories: subgroup 1 (SG1), subgroup 2 (SG2), no subgroup membership ('None'), and mixed SG1 + SG2 subgroups ('Mixed'). Voxel-wise analyses characterized SG1 and SG2 subgroups. Supervised machine learning analyses characterized baseline and remission signatures related to SG1 and SG2 membership. The two dominant patterns of 'lower brain volume' in SG1 and 'higher striatal volume' (with otherwise normal neuromorphology) in SG2 were identified already at the first episode of psychosis. SG1 had a significantly higher proportion of FEP (32%) vs. HC (19%) than SG2 (FEP, 21%; HC, 23%). Clinical multivariate signatures separated the SG1 and SG2 subgroups (balanced accuracy = 64%; p < 0.0001), with SG2 showing higher education but also greater positive psychosis symptoms at first presentation, and an association with symptom remission at 1-year, 5-year, and when timepoints were combined. Neuromorphological subtypes of schizophrenia are already evident at illness onset, separated by distinct clinical presentations, and differentially associated with subsequent remission. These results suggest that the subgroups may be underlying risk phenotypes that could be targeted in future treatment trials and are critical to consider when interpreting neuroimaging literature.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Brasil , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética
8.
Clin Exp Rheumatol ; 42(7): 1451-1458, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38451142

RESUMO

OBJECTIVES: Transcranial direct current stimulation (tDCS) combined with aerobic exercise (tDCS-AE) effectively reduces fatigue in patients with fibromyalgia. However, no study has assessed this method in systemic lupus erythematosus (SLE) patients with significant fatigue. Therefore, we evaluated the safety and efficacy of tDCS-AE for significant fatigue symptoms in adult female SLE patients. METHODS: This randomised, sham-controlled, double-blind study included 25 patients with SLE in remission or low disease activity (SLEDAI-2K £4) and with significant fatigue [≥36 points on the Fatigue Severity Scale (FSS) or ≥38 points on the Modified Fatigue Scale (MFIS)]. The patients received sham or tDCS for five consecutive days. The anode and cathode were positioned at M1 and Fp2, respectively (international 10-20 EEG system). tDCS was applied at an intensity of 2mA, and density of 0.057mA/cm2 in the tDCS-AE group. Both groups underwent combined low-intensity treadmill exercise. FSS, MFIS, pain visual analogue scale, physical activity, and sleep quality were evaluated at baseline and on days 7, 30, and 60. Adherence and safety were assessed using a standardised questionnaire. RESULTS: Improvement in fatigue levels was observed in both groups. However, a sustained reduction in fatigue levels on days 30 and 60 occurred only with tDCS-AEs (p<0.05). No significant differences were observed in pain level, sleep quality, or physical activity. No disease flares occurred and the adverse effects were mild and transient. Finally, the patient's adherence to the treatment was satisfactory. CONCLUSIONS: Despite isolated AEs, there was an improvement in fatigue, however, only tDCS-AE maintained significant and sustained improvement.


Assuntos
Fadiga , Lúpus Eritematoso Sistêmico , Estimulação Transcraniana por Corrente Contínua , Humanos , Método Duplo-Cego , Feminino , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/terapia , Lúpus Eritematoso Sistêmico/fisiopatologia , Lúpus Eritematoso Sistêmico/diagnóstico , Fadiga/etiologia , Fadiga/terapia , Fadiga/fisiopatologia , Adulto , Pessoa de Meia-Idade , Resultado do Tratamento , Terapia por Exercício/métodos , Exercício Físico , Índice de Gravidade de Doença , Fatores de Tempo , Qualidade do Sono
9.
Brain ; 146(10): 4191-4199, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37170631

RESUMO

COQ7 encodes a hydroxylase responsible for the penultimate step of coenzyme Q10 (CoQ10) biosynthesis in mitochondria. CoQ10 is essential for multiple cellular functions, including mitochondrial oxidative phosphorylation, lipid metabolism, and reactive oxygen species homeostasis. Mutations in COQ7 have been previously associated with primary CoQ10 deficiency, a clinically heterogeneous multisystemic mitochondrial disorder. We identified COQ7 biallelic variants in nine families diagnosed with distal hereditary motor neuropathy with upper neuron involvement, expending the clinical phenotype associated with defects in this gene. A recurrent p.Met1? change was identified in five families from Brazil with evidence of a founder effect. Fibroblasts isolated from patients revealed a substantial depletion of COQ7 protein levels, indicating protein instability leading to loss of enzyme function. High-performance liquid chromatography assay showed that fibroblasts from patients had reduced levels of CoQ10, and abnormal accumulation of the biosynthetic precursor DMQ10. Accordingly, fibroblasts from patients displayed significantly decreased oxygen consumption rates in patients, suggesting mitochondrial respiration deficiency. Induced pluripotent stem cell-derived motor neurons from patient fibroblasts showed significantly increased levels of extracellular neurofilament light protein, indicating axonal degeneration. Our findings indicate a molecular pathway involving CoQ10 biosynthesis deficiency and mitochondrial dysfunction in patients with distal hereditary motor neuropathy. Further studies will be important to evaluate the potential benefits of CoQ10 supplementation in the clinical outcome of the disease.


Assuntos
Doenças Mitocondriais , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Neurônios Motores/metabolismo , Mutação/genética , Ubiquinona/genética
10.
BMC Vet Res ; 20(1): 58, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374006

RESUMO

BACKGROUND: Staphylococcus spp and Microsporum canis are zoonotic microorganisms which can cause infections and systemic diseases. The bone infection is usually caused by invasion of pathogen through the hematologic route. Mixed osteomyelitis caused by bacteria and fungi is rare, and to date, there have been no reports of mixed osteomyelitis with Staphylococcus spp. and Microsporum canis. CASE PRESENTATION: This essay reports an atypical presentation of mixed osteomyelitis (Staphylococcus spp. and Microsporum canis) in a domestic cat. A 15-month-old female Persian cat was presented to a veterinary service; the main complaint was the appearance of a nodule in the mandibular ventral rostral region. A radiographic exam performed on the animal showed proliferative and osteolytic bone lesions. The patient was submitted to a biopsy for histopathological evaluation, along with bacterial and fungal cultures. Results showed mixed osteomyelitis by Staphylococcus spp. and Microsporum canis. Microbial Sensitivity Test was performed to choose a more suitable treatment. Two surgical procedures were executed to resect and curette the lesion, and treatments with anti-inflammatory, antibiotic, and antifungal drugs were established, showing a positive clinical evolution. After 8 months of treatment, the patient's owner moved to a different city, and the animal was seen by other veterinarians, who followed along with the same treatment. However, due to complications and a diminishing quality of life over 4 years of diagnosis, the patient was euthanized. CONCLUSION: Given the above, mixed osteomyelitis is difficult to treat and can cause losses of life quality resulting death, especially in infections where M. canis is the agent causing the disease. Bacterial osteomyelitis is more frequently reported. But the lack of investigation of microorganisms other than bacteria, such as fungal cases, may imply in underdiagnosed cases. Treatment of osteomyelitis can be difficult considering the difficulties in isolating the pathological agent, resistance to the drug used, prolonged treatment time, and cost.


Assuntos
Doenças do Gato , Dermatomicoses , Microsporum , Osteomielite , Gatos , Feminino , Animais , Dermatomicoses/veterinária , Qualidade de Vida , Antifúngicos/uso terapêutico , Osteomielite/tratamento farmacológico , Osteomielite/veterinária , Doenças do Gato/tratamento farmacológico
11.
Phytopathology ; : PHYTO05230175R, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37942874

RESUMO

Phytophthora cactorum is the most common causal agent of Phytophthora crown rot and leather rot of strawberry, but P. nicotianae is also responsible for the disease in Florida. Studies of P. nicotianae populations have suggested that different groups of genotypes are associated with different hosts; however, it is not yet clear how many lineages exist globally and how they are related to different production systems. The aim of this study was to determine the genetic relationships of P. nicotianae isolates from Florida strawberry with genotypes reported from other hosts, quantify the genetic variation on strawberry, and test for an association with nursery source. A total of 49 isolates of P. nicotianae were collected from strawberry plants originating from multiple nursery sources during six seasons of commercial fruit production in Florida. Microsatellite genotyping identified 28 multilocus genotypes on strawberry that were distinct among 208 isolates originating from various hosts and locations. Based on STRUCTURE analysis, two genetic groups were identified: one consisting of isolates from strawberry, and the other comprising samples from different hosts. Multilocus genotypes were shared among nursery sources, and populations defined by nursery were not differentiated. Both mating types were found among the isolates from North Carolina- and California-origin plants and in most strawberry seasons; however, a predominance of A1 was observed, and regular sexual reproduction was not supported by the data. This study reveals a unique genetic population of P. nicotianae associated with strawberry and emphasizes the vital role of nursery monitoring in mitigating disease spread.

12.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33727422

RESUMO

Cyanobacteriochromes (CBCRs) are small, linear tetrapyrrole (bilin)-binding photoreceptors in the phytochrome superfamily that regulate diverse light-mediated adaptive processes in cyanobacteria. More spectrally diverse than canonical red/far-red-sensing phytochromes, CBCRs were thought to be restricted to sensing visible and near UV light until recently when several subfamilies with far-red-sensing representatives (frCBCRs) were discovered. Two of these frCBCRs subfamilies have been shown to incorporate bilin precursors with larger pi-conjugated chromophores, while the third frCBCR subfamily uses the same phycocyanobilin precursor found in the bulk of the known CBCRs. To elucidate the molecular basis of far-red light perception by this third frCBCR subfamily, we determined the crystal structure of the far-red-absorbing dark state of one such frCBCR Anacy_2551g3 from Anabaena cylindrica PCC 7122 which exhibits a reversible far-red/orange photocycle. Determined by room temperature serial crystallography and cryocrystallography, the refined 2.7-Å structure reveals an unusual all-Z,syn configuration of the phycocyanobilin (PCB) chromophore that is considerably less extended than those of previously characterized red-light sensors in the phytochrome superfamily. Based on structural and spectroscopic comparisons with other bilin-binding proteins together with site-directed mutagenesis data, our studies reveal protein-chromophore interactions that are critical for the atypical bathochromic shift. Based on these analyses, we propose that far-red absorption in Anacy_2551g3 is the result of the additive effect of two distinct red-shift mechanisms involving cationic bilin lactim tautomers stabilized by a constrained all-Z,syn conformation and specific interactions with a highly conserved anionic residue.


Assuntos
Pigmentos Biliares/química , Pigmentos Biliares/metabolismo , Cianobactérias/fisiologia , Modelos Moleculares , Fitocromo/química , Fitocromo/metabolismo , Conformação Proteica , Luz , Optogenética , Relação Estrutura-Atividade , Raios Ultravioleta
13.
Sensors (Basel) ; 24(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38931556

RESUMO

This paper reports a rapid and sensitive sensor for the detection and quantification of the COVID-19 N-protein (N-PROT) via an electrochemical mechanism. Single-frequency electrochemical impedance spectroscopy was used as a transduction method for real-time measurement of the N-PROT in an immunosensor system based on gold-conjugate-modified carbon screen-printed electrodes (Cov-Ag-SPE). The system presents high selectivity attained through an optimal stimulation signal composed of a 0.0 V DC potential and 10 mV RMS-1 AC signal at 100 Hz over 300 s. The Cov-Ag-SPE showed a log response toward N-PROT detection at concentrations from 1.0 ng mL-1 to 10.0 µg mL-1, with a 0.977 correlation coefficient for the phase (θ) variation. An ML-based approach could be created using some aspects observed from the positive and negative samples; hence, it was possible to classify 252 samples, reaching 83.0, 96.2 and 91.3% sensitivity, specificity, and accuracy, respectively, with confidence intervals (CI) ranging from 73.0 to 100.0%. Because impedance spectroscopy measurements can be performed with low-cost portable instruments, the immunosensor proposed here can be applied in point-of-care diagnostics for mass testing, even in places with limited resources, as an alternative to the common diagnostics methods.


Assuntos
Técnicas Biossensoriais , COVID-19 , Espectroscopia Dielétrica , Ouro , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/virologia , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Humanos , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/imunologia , Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Ouro/química , Eletrodos , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Imunoensaio/métodos , Imunoensaio/instrumentação , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/análise , Carbono/química , Fosfoproteínas/análise
14.
Exp Appl Acarol ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995470

RESUMO

Phytoseiid predatory mites are one of the most important groups of biocontrol agents, commonly used in biological control. The ability to produce these predatory mites economically, at high density on cheap factitious food sources, is a major contributor to their success. Astigmatid mites are the most widely used factitious food for this purpose. In this study, we investigated the potential application of the leaf-dwelling astigmatid mite Czenspinskia transversostriata (Oudemans) (Acari: Winterschmidtiidae) as a prey mite in biological control. We tested whether C. transversostriata is a suitable food source for the predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae), both in the laboratory and on cucumber plants. Based on a reproduction trial, C. transversostriata proved to be an equally good food source compared to both pollen of Typha angustifolia L. (Poales: Typhaceae) and a frequently used prey mite Carpoglyphus lactis L. (Acari: Carpoglyphidae). In a pre-establishment trial on cucumber plants, populations of A. swirskii reached equally high densities when supplemented with C. transversostriata, compared to C. lactis. Lastly, we show that C. transversostriata is capable of feeding and reproducing on powdery mildew growing on cucumber plants, thereby slowing down the development of the pathogenic fungus. Results derived from this study show that C. transversostriata may have multiple potential applications in biological control programs.

15.
Syst Parasitol ; 101(3): 35, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700732

RESUMO

Two new species of Urocleidoides are described from the gills of Pseudanos trimaculatus (Characiformes: Anostomidae) from the coastal drainages of the Eastern Amazon, Brazil. Urocleidoides itabocaensis n. sp. is characterized by having a sclerotized, tubular, sigmoid male copulatory organ (MCO), a circular sclerotized tandem brim associated with the base of the MCO; an accessory piece articulated with the MCO, a V-shaped, divided into two subunits, distal subunit spoon-shaped; and a vaginal pore dextroventral with opening marginal. Urocleidoides omphalocleithrum n. sp. is characterized by presenting a C-shaped or sigmoid MCO; an accessory piece articulated with the MCO, L-shaped, divided into two subunits, distal subunit gutter-shaped; a vaginal pore dextroventral with opening marginal; and a ventral bar broadly V-shaped, with anteromedial projection. Molecular phylogenetic analysis based on partial 28S rDNA and COI mtDNA genes indicate that U. itabocaensis n. sp. and U. omphalocleithrum n. sp. are closely related and appear as a sister group to other Urocleidoides species (U. paradoxus, U. digitabulum and U. sinus) parasitizing anostomid fishes. This study represents the first record of monogenoids from the gills of P. trimaculatus for the Eastern Amazon.


Assuntos
Caraciformes , Filogenia , Especificidade da Espécie , Animais , Brasil , Caraciformes/parasitologia , Brânquias/parasitologia , Trematódeos/classificação , Trematódeos/genética , Trematódeos/anatomia & histologia , RNA Ribossômico 28S/genética , Masculino
16.
Malar J ; 22(1): 306, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817240

RESUMO

BACKGROUND: Imperfect adherence is a major barrier to effective primaquine radical cure of Plasmodium vivax. This study investigated the effect of reduced adherence on the risk of P. vivax recurrence. METHODS: Efficacy studies of patients with uncomplicated P. vivax malaria, including a treatment arm with daily primaquine, published between January 1999 and March 2020 were identified. Individual patient data from eligible studies were pooled using standardized methodology. Adherence to primaquine was inferred from i) the percentage of supervised doses and ii) the total mg/kg dose received compared to the target total mg/kg dose per protocol. The effect of adherence to primaquine on the incidence of P. vivax recurrence between days 7 and 90 was investigated by Cox regression analysis. RESULTS: Of 82 eligible studies, 32 were available including 6917 patients from 18 countries. For adherence assessed by percentage of supervised primaquine, 2790 patients (40.3%) had poor adherence (≤ 50%) and 4127 (59.7%) had complete adherence. The risk of recurrence by day 90 was 14.0% [95% confidence interval: 12.1-16.1] in patients with poor adherence compared to 5.8% [5.0-6.7] following full adherence; p = 0.014. After controlling for age, sex, baseline parasitaemia, and total primaquine dose per protocol, the rate of the first recurrence was higher following poor adherence compared to patients with full adherence (adjusted hazard ratio (AHR) = 2.3 [1.8-2.9]). When adherence was quantified by total mg/kg dose received among 3706 patients, 347 (9.4%) had poor adherence, 88 (2.4%) had moderate adherence, and 3271 (88.2%) had complete adherence to treatment. The risks of recurrence by day 90 were 8.2% [4.3-15.2] in patients with poor adherence and 4.9% [4.1-5.8] in patients with full adherence; p < 0.001. CONCLUSION: Reduced adherence, including less supervision, increases the risk of vivax recurrence.


Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária Vivax , Humanos , Primaquina/efeitos adversos , Antimaláricos/farmacologia , Plasmodium vivax , Recidiva , Malária Vivax/tratamento farmacológico , Malária Vivax/prevenção & controle , Malária Vivax/complicações , Antagonistas do Ácido Fólico/farmacologia
17.
Oecologia ; 201(4): 929-939, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36947271

RESUMO

Two mutually unexclusive hypotheses prevail in the theory of nutritional ecology: the balanced diet hypothesis states that consumers feed on different food items because they have complementary nutrient and energy compositions. The toxin-dilution hypothesis poses that consumers feed on different food items to dilute the toxins present in each. Both predict that consumers should not feed on low-quality food when ample high-quality food forming a complete diet is present. We investigated the diet choice of Phytoseiulus persimilis, a predatory mite of web-producing spider mites. It can develop and reproduce on single prey species, for example the spider mite Tetranychus urticae. A closely related prey, T. evansi, is of notorious bad quality for P. persimilis and other predator species. We show that juvenile predators feeding on this prey have low survival and do not develop into adults. Adults stop reproducing and have increased mortality when feeding on it. Feeding on a mixed diet of the two prey decreases predator performance, but short-term effects of feeding on the low-quality prey can be partially reversed by subsequently feeding on the high-quality prey. Yet, predators consume low-quality prey in the presence of high-quality prey, which is in disagreement with both hypotheses. We suggest that it is perhaps not the instantaneous reproduction on single prey or mixtures of prey that matters for the fitness of predators, but that it is the overall reproduction by a female and her offspring on an ephemeral prey patch, which may be increased by including inferior prey in their diet.


Assuntos
Dieta , Reprodução , Tetranychidae , Animais , Feminino , Ecologia , Cadeia Alimentar , Comportamento Predatório
18.
Parasitology ; 150(2): 184-194, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36444641

RESUMO

Due to their high specificity, monogenoids from fish provide an interesting model to study historical associations of hosts and parasites. High agreement between host and parasite phylogeny is often interpreted as evidence of cospeciation. However, cophylogenetic signal may also arise from other, either adaptive or non-adaptive, processes. We applied the recently developed Cophylospace Framework to better understand the evolutionary relationship between monogenoids and marine catfish from the Atlantic coast of South America. The associations between 12 marine catfish and 10 monogenoid species were assessed. Molecular data of host and parasite species were used for phylogenetic reconstruction. We used anchor morphology based on Procrustes coordinates to evaluate whether closely related hosts are associated with morphologically similar parasites. To assess the association between parasite phylogeny and host morphology, we produced a distance matrix based on morphological characters of catfishes. Agreement between phylogenies and between phylogeny and morphology was measured using Procrustes R2 computed with PACo. The parasite phylogeny obtained in this study represents the first complete phylogenetic hypothesis of monogenoids parasitizing ariids from South America. The Cophylospace analysis suggested that phylogenetic and morphological distance of monogenoids contributes similarly to explain the pattern of host­parasite associations, whereas parasite phylogeny is more strongly associated with the morphological traits of the hosts than with host phylogeny. This evidence suggests that cospeciation is not a major force accounting for diversification in the monogenoids studied. Rather host morphological traits seem to be a more important driver, which conforms with evidence from other host‒monogenoid systems.


Assuntos
Peixes-Gato , Parasitos , Trematódeos , Animais , Filogenia , Peixes-Gato/parasitologia , Evolução Biológica , Interações Hospedeiro-Parasita , América do Sul
19.
Int Urogynecol J ; 34(7): 1599-1605, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36645440

RESUMO

INTRODUCTION AND HYPOTHESIS: The objective was to investigate the incidence and risk factors of postoperative de novo stress urinary incontinence (SUI) in stress-continent women following minimally invasive sacrocolpopexy without an anti-incontinence procedure. METHODS: We completed a multicenter, retrospective cohort study of women undergoing laparoscopic sacrocolpopexy without concurrent anti-incontinence procedures from October 2006 through January 2021. RESULTS: Of the 169 women who underwent minimally invasive sacrocolpopexy, 17.1% (n=30) developed de novo SUI, and 7.1% eventually underwent a midurethral sling placement. On logistic regression, BMI, preoperative urinary urgency, and history of transvaginal mesh repair were found to be significantly associated with and predictive of de novo SUI. When the concordance index (C-index) was calculated with the model published by Jelovsek et al. for women who developed de novo SUI within 12 months of the prolapse surgery, the current de novo SUI calculator was able to discriminate de novo SUI outcome (C-index = 0.71). CONCLUSIONS: The incidence of de novo SUI after minimally invasive sacrocolpopexy without anti-incontinence procedure correlates directly with higher BMI, preoperative urinary urgency, and transvaginal mesh history for POP. Preoperative counseling for minimally invasive sacrocolpopexy should include discussing the risk of de novo SUI and preoperative factors that may increase this risk.


Assuntos
Prolapso de Órgão Pélvico , Slings Suburetrais , Incontinência Urinária por Estresse , Feminino , Humanos , Prolapso de Órgão Pélvico/cirurgia , Prolapso de Órgão Pélvico/complicações , Incontinência Urinária por Estresse/epidemiologia , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/cirurgia , Incidência , Estudos Retrospectivos , Slings Suburetrais/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
20.
Appl Opt ; 62(8): C53-C58, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-37133058

RESUMO

The luminescence of skim milk samples with distinct protein content doped with rhodamine B was investigated. The samples were excited by a nanosecond laser tuned at 532 nm, and the emission was characterized as a random laser. Its features were analyzed as a function of the protein aggregate content. The results showed a linear correlation between the random laser peak intensity and the protein content. This paper proposes a rapid detection photonic method to evaluate the protein content in skim milk based on the intensity of the random laser emission.


Assuntos
Lasers , Leite , Animais
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