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3.
Artigo em Inglês | MEDLINE | ID: mdl-39067621

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide with its incidence on the rise globally. This paper provides a comprehensive review of prognostic imaging markers in HCC, emphasizing their role in risk stratification and clinical decision-making. We explore quantitative and qualitative criteria derived from imaging studies, such as computed tomography and magnetic resonance imaging, which can offer valuable insights into the biological behavior of the tumor. While many of these markers are not yet widely integrated into current clinical guidelines, they represent a promising future direction for approaching this highly heterogeneous cancer. However, standardization and validation of these markers remain important challenges. We conclude by emphasizing the importance of ongoing research to enhance clinical practices and improve outcomes for patients with HCC.

4.
Theriogenology ; 227: 21-30, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38996526

RESUMO

Poor sperm quality in cooled-shipped semen has been related to subpar fertility in horses. Therefore, this study aimed to evaluate the ability of post-cooling sperm processing to improve sperm parameters of cooled-stored stallion semen for artificial insemination. For all experiments, ejaculates were collected, processed, and diluted in skimmed milk-based (SM) medium and stored at 5 °C/24h. In all experiments an aliquot of unprocessed cooled semen was used as a control. In the first experiment (Exp 1.), cooled-stored semen from 16 stallions (n = 32) was processed by SpermFilter or centrifugation (600×g/10min) and resuspended in an egg yolk-based freezing medium containing permeating cryoprotectants (EY-C) for cryopreservation. Sperm recovery and motility parameters were immediately assessed after sperm resuspension in both groups and compared with unprocessed (Unp) samples. In Exp 2., cooled semen samples from six stallions (n = 18) were processed using SpermFilter and resuspended in SM or EY-C. Motility parameters and plasma membrane integrity were assessed in all groups (Unp, SM, and EY-C). In Exp 3, cooled semen from four stallions (n = 20) was processed by SpermFilter, resuspended in SM, EY-C, or egg yolk-based medium without cryoprotectants (EY-nC); and submitted to a thermoresistance test (37 °C/3h). Motility parameters, plasma membrane integrity and stability, mitochondrial membrane potential, mitochondrial superoxide generation, and DNA fragmentation index were evaluated in all groups. Finally, in Exp 4, 39 estrous cycles of 11 mares were inseminated with unprocessed (n = 6) cooled-stored semen or semen cooled at 5 °C/24h and then processed by SpermFilter and resuspended in SM (n = 5), EY-C (n = 11), EY-nC (n = 11), or centrifuged and resuspended in EY-C (n = 6). Overall, semen processing and resuspension in EY mediums (EY-C and EY-nC) improved sperm parameters compared with those of unprocessed semen (P < 0.05). Centrifugation (91 ± 5 %) recovered more sperm than SpermFilter (84 ± 9 %; P < 0.05). Sperm resuspended in EY-nC maintained better sperm parameters throughout the thermoresistance test than those in the other groups (P < 0.05). The fertility rates were similar between all groups (P > 0.05). In conclusion, processing and resuspension in EY medium can improve sperm parameters in post-cooled-stored stallion semen.


Assuntos
Criopreservação , Análise do Sêmen , Preservação do Sêmen , Animais , Cavalos/fisiologia , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Masculino , Análise do Sêmen/veterinária , Criopreservação/veterinária , Criopreservação/métodos , Espermatozoides/fisiologia , Motilidade dos Espermatozoides , Crioprotetores/farmacologia , Temperatura Baixa
6.
Environ Res ; 259: 119475, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945513

RESUMO

Avian droppings (combination of fecal matter and urates) provide a non-lethal and non-invasive matrix for measuring pesticide exposures. In the field, droppings may be collected days or weeks after excretion and the persistence of pesticide residues in weathered droppings is not known. Thus, we studied the effects of weathering on pesticide residues in droppings. Domestic chicken (Gallus gallus domesticus) hens were used as a representative species for Order Galliformes. We collected droppings from hens before they were exposed to the pesticides (reference or pre-dose droppings ). Thereafter, the hens were orally administered encapsulated wheat seeds coated with Raxil® PRO Shield (containing the active ingredients imidacloprid, prothioconazole, metalaxyl, and tebuconazole) for consecutive 7 days. During this time, their droppings were collected on days 3, 5, and 8 from the start of the exposure period (post-dose droppings ). The pre-dose and post-dose droppings were weathered for up to 30 days in autumn and spring in shrubsteppe habitat. Droppings were analyzed using HPLC coupled to triple quad LC/MS for parent compound and metabolite residues. No pesticide or its metabolite residues were detected in the weathered reference droppings. No parent pesticide compounds were detected in weathered post-dose droppings but imidacloprid metabolites, imidacloprid-5-hydroxy and imidacloprid-olefin, and the prothioconazole metabolite, desthio-prothioconazole, were detected in all post-dose weathered samples from both seasons. The active ingredients metalaxyl and tebuconazole and their metabolites were not detected in any of the samples. Our results suggest that, depending on the pesticide, its concentration, and the environmental conditions, residues of some pesticides can be detected in droppings weathered for at least 30 days. Knowledge of pesticide persistence in weathered droppings can help refine the quality and quantity of fecal samples that are collected for monitoring pesticide exposures to birds.

7.
Brain Sci ; 14(5)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38790414

RESUMO

Psychostimulants alter cellular morphology and activate neuroimmune signaling in a number of brain regions, yet few prior studies have investigated their persistence beyond acute abstinence or following high levels of voluntary drug intake. In this study, we examined the effects of the repeated binge-like self-administration (96 h/week for 3 weeks) of methamphetamine (METH) and 21 days of abstinence in female and male rats on changes in cell density, morphology, and cytokine levels in two addiction-related brain regions-the prefrontal cortex (PFC) and dorsal striatum (DStr). We also examined the effects of similar patterns of intake of the cocaine-like synthetic cathinone derivative 3,4-methylenedioxypyrovalerone (MDPV) or saline as a control. Robust levels of METH and MDPV intake (~500-1000 infusions per 96 h period) were observed in both sexes. We observed no changes in astrocyte or neuron density in either region, but decreases in dendritic spine densities were observed in PFC pyramidal and DStr medium spiny neurons. The microglial cell density was decreased in the PFC of METH self-administering animals, accompanied by evidence of microglial apoptosis. Changes in microglial morphology (e.g., decreased territorial volume and ramification and increased cell soma volume) were also observed, indicative of an inflammatory-like state. Multiplex analyses of PFC and DStr cytokine content revealed elevated levels of various interleukins and chemokines only in METH self-administering animals, with region- and sex-dependent effects. Our findings suggest that voluntary binge-like METH or MDPV intake induces similar cellular perturbations in the brain, but they are divergent neuroimmune responses that persist beyond the initial abstinence phase.

8.
Res Pract Thromb Haemost ; 8(3): 102397, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38689619

RESUMO

Background: Pharmacokinetic (PK)-guided dosing is used to individualize factor (F)VIII and FIX replacement therapy. Objectives: This study investigates the reliability and feasibility of PK-guided prophylactic dosing of factor concentrates in hemophilia A and B. Methods: In this multicenter, prospective cohort study, people of all ages with hemophilia received prophylactic treatment with factor concentrates based on individual PK parameters. During follow-up, at least 4 measured FVIII/FIX levels per patient were compared with corresponding predicted levels obtained by Bayesian forecasting. Predictive performance was defined as adequate when ≥80% of measured FVIII/FIX levels were within ±25% of prediction (relative error). Additionally, mean absolute error and mean error were calculated. In post hoc analyses, predictive performance was assessed allowing maximum absolute errors of 1 (trough), 5 (mid), and 15 (peak) IU/dL. Five-point scale questionnaires addressed feasibility of PK guidance. Results: We included 50 patients (median age, 19 years; range: 2-72 years). Median follow-up was 36 weeks. Seventy-one percent of levels (58% trough, 83% mid, and 80% peak) were within ±25% of prediction. Mean absolute errors were 0.8 (trough), 2.0 (mid), and 8.6 (peak) IU/dL. In post hoc analyses, 81% (trough), 96% (mid), and 82% (peak) of levels were within set limits. Patients reported low burden and high satisfaction. Conclusion: PK-guided dosing was reliable according to post hoc analyses, based on low absolute errors that were regarded as clinically irrelevant in most cases. The predefined predictive performance was achieved in mid and peak factor levels but not in trough factor levels due to measurement inaccuracy. PK guidance also seemed feasible.

9.
Acta Trop ; 256: 107265, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38772434

RESUMO

In this present study, carried out between November 2020 and July 2023 at Londrina's University Hospital, patients with active lesions of cutaneous leishmaniasis (CL) were analyzed regarding pain perception and anatomopathological aspects of the ulcers. Pain was assessed using a numerical rating scale (NRS) to compare five patients diagnosed with CL with four control patients diagnosed with vascular skin ulcers. Histopathological evaluations were used to investigate the nociceptor neuron-Leishmania interface. Patients with CL ulcers reported less pain compared to patients with vascular ulcers (2.60 ± 2.30 and 7.25 ± 0.95, respectively, p = 0.0072). Histopathology evidenced Leishmania spp. amastigote forms nearby sensory nerve fibers in profound dermis. Schwann cells marker (S100 protein) was detected, and caspase-3 activation was not evidenced in the in the nerve fibers of CL patients' samples, suggesting absence of apoptotic activity in nerve endings. Additionally, samples taken from the active edge of the lesion were negative for bacilli acid-alcohol resistant (BAAR), which excludes concomitant leprosy, in which painless lesions are also observed. Thus, the present data unveil for the first time anatomopathological and microbiological details of painless ulcers in CL patients, which has important clinical implications for a better understanding on the intriguing painless clinical characteristic of CL.


Assuntos
Apoptose , Leishmania , Leishmaniose Cutânea , Úlcera Cutânea , Humanos , Masculino , Feminino , Leishmaniose Cutânea/patologia , Leishmaniose Cutânea/parasitologia , Adulto , Pessoa de Meia-Idade , Úlcera Cutânea/parasitologia , Úlcera Cutânea/patologia , Células Receptoras Sensoriais/patologia , Neurônios/patologia , Idoso , Pele/parasitologia , Pele/patologia , Pele/inervação
10.
Animals (Basel) ; 14(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38672316

RESUMO

The use of omeprazole as a preventive treatment for gastrointestinal ulcers in veterinary medicine has been questioned during previous years. The aim of the present study is to assess the long-term effect of omeprazole on cobalamin and serum gastrin levels in healthy dogs. Eighteen healthy dogs were included: 10 in the control group and 8 in the omeprazole group. Three samples were collected: before starting the treatment (T0), 30 days after the start of treatment (T1), and at 60 days (T2). The mean cobalamin value (ng/L) in the control group was 481.4 (±293.70) at T0, 481.4 (±170.21) at T1, and 513.2 (±174.50) at T2. In the omeprazole group, the values were 424.62 (±161.57) at T0, 454.5 (±160.96) at T1, and 414.87 (±127.90) at T2. No statistically significant changes were detected in cobalamin levels between the three-time period in both study groups. These results agree with previous findings in felines but contrast with human medicine studies. The median gastrin values (pg/mL) in the control group were 62.45 [30.17-218.75] at T0, 76.06 [30.67-199.87] at T1, and 63.02 [35.81-176.06] at T2. The median gastrin value in the omeprazole group was 67.59 [55.96-101.60] at T0, 191.77 [75.31-1901.77] at T1, and 128.16 [43.62-1066.46] at T2. Statistically significant differences were detected (p = 0.008), indicating an increase in gastrin levels after initiating treatment with omeprazole. In conclusion, the increased levels of gastrin observed in this population underscore the importance of conducting a comprehensive clinical assessment to identify potential gastrointestinal disorders, particularly in consideration of the usage of omeprazole as a preventive treatment.

11.
PLoS Biol ; 22(4): e3002566, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38652717

RESUMO

Phage therapy is a therapeutic approach to treat multidrug-resistant (MDR) infections that employs lytic bacteriophages (phages) to eliminate bacteria. Despite the abundant evidence for its success as an antimicrobial in Eastern Europe, there is scarce data regarding its effects on the human host. Here, we aimed to understand how lytic phages interact with cells of the airway epithelium, the tissue site that is colonized by bacterial biofilms in numerous chronic respiratory disorders. Using a panel of Pseudomonas aeruginosa phages and human airway epithelial cells (AECs) derived from a person with cystic fibrosis (CF), we determined that interactions between phages and epithelial cells depend on specific phage properties as well as physiochemical features of the microenvironment. Although poor at internalizing phages, the airway epithelium responds to phage exposure by changing its transcriptional profile and secreting antiviral and proinflammatory cytokines that correlate with specific phage families. Overall, our findings indicate that mammalian responses to phages are heterogenous and could potentially alter the way that respiratory local defenses aid in bacterial clearance during phage therapy. Thus, besides phage receptor specificity in a particular bacterial isolate, the criteria to select lytic phages for therapy should be expanded to include mammalian cell responses.


Assuntos
Fibrose Cística , Citocinas , Células Epiteliais , Pseudomonas aeruginosa , Humanos , Pseudomonas aeruginosa/virologia , Células Epiteliais/virologia , Células Epiteliais/metabolismo , Células Epiteliais/imunologia , Citocinas/metabolismo , Fibrose Cística/terapia , Fibrose Cística/imunologia , Fibrose Cística/metabolismo , Terapia por Fagos , Bacteriófagos/fisiologia , Bacteriófagos/genética , Mucosa Respiratória/virologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/imunologia , Infecções por Pseudomonas/terapia , Infecções por Pseudomonas/imunologia , Fagos de Pseudomonas/metabolismo , Biofilmes
12.
Proc Natl Acad Sci U S A ; 121(18): e2318666121, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38652747

RESUMO

In bacteria, intracellular K+ is involved in the regulation of membrane potential, cytosolic pH, and cell turgor as well as in spore germination, environmental adaptation, cell-to-cell communication in biofilms, antibiotic sensitivity, and infectivity. The second messenger cyclic-di-AMP (c-di-AMP) has a central role in modulating the intracellular K+ concentration in many bacterial species, controlling transcription and function of K+ channels and transporters. However, our understanding of how this regulatory network responds to c-di-AMP remains poor. We used the RCK (Regulator of Conductance of K+) proteins that control the activity of Ktr channels in Bacillus subtilis as a model system to analyze the regulatory function of c-di-AMP with a combination of in vivo and in vitro functional and structural characterization. We determined that the two RCK proteins (KtrA and KtrC) are neither physiologically redundant or functionally equivalent. KtrC is the physiologically dominant RCK protein in the regulation of Ktr channel activity. In explaining this hierarchical organization, we found that, unlike KtrA, KtrC is very sensitive to c-di-AMP inactivation and lack of c-di-AMP regulation results in RCK protein toxicity, most likely due to unregulated K+ flux. We also found that KtrC can assemble with KtrA, conferring c-di-AMP regulation to the functional KtrA/KtrC heteromers and potentially compensating KtrA toxicity. Altogether, we propose that the central role of c-di-AMP in the control of the K+ machinery, by modulating protein levels through gene transcription and by regulating protein activity, has determined the evolutionary selection of KtrC as the dominant RCK protein, shaping the hierarchical organization of regulatory components of the K+ machinery.


Assuntos
Bacillus subtilis , Proteínas de Bactérias , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Bacillus subtilis/metabolismo , Bacillus subtilis/genética , Potássio/metabolismo , Regulação Bacteriana da Expressão Gênica , Fosfatos de Dinucleosídeos/metabolismo , Canais de Potássio/metabolismo , Canais de Potássio/genética
13.
Braz J Med Biol Res ; 57: e13282, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656072

RESUMO

Sarcopenia is a pathology resulting from a progressive and severe loss of muscle mass, strength, and function in the course of aging, which has deleterious consequences on quality of life. Among the most widespread studies on the issue are those focused on the effect of different types of physical exercise on patients with sarcopenia. This randomized controlled study aimed to compare the effects of a whole-body vibration exercise (WBV) session on the inflammatory parameters of non-sarcopenic (NSG, n=22) and sarcopenic elderly (SG, n=22). NSG and SG participants were randomly divided into two protocols: intervention (squat with WBV) and control (squat without WBV). After a one-week washout period, participants switched protocols, so that everyone performed both protocols. Body composition was assessed by dual-energy radiological absorptiometry (DXA) and function through the six-minute walk test (6MWD) and Short Physical Performance Battery (SPPB). Plasma soluble tumor necrosis factor receptors (sTNFR) were determined by enzyme-linked immunosorbent assay (ELISA) and measured before and immediately after each protocol. After exercise with WBV, there was an increase in sTNFR2 levels in the NSG (P<0.01; d=-0.69 (-1.30; -0.08) and SG (P<0.01, d=-0.95 (-1.57; -0.32) groups. In conclusion, an acute session of WBV influenced sTNFr2 levels, with sarcopenic individuals showing a greater effect. This suggested that WBV had a more pronounced impact on sTNFr2 in those with loss of muscle strength and/or physical performance. Additionally, WBV is gaining recognition as an efficient strategy for those with persistent health issues.


Assuntos
Sarcopenia , Vibração , Humanos , Sarcopenia/sangue , Sarcopenia/terapia , Vibração/uso terapêutico , Idoso , Masculino , Feminino , Receptores do Fator de Necrose Tumoral/sangue , Ensaio de Imunoadsorção Enzimática , Composição Corporal/fisiologia , Força Muscular/fisiologia , Absorciometria de Fóton , Terapia por Exercício/métodos , Resultado do Tratamento , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Qualidade de Vida
14.
Expert Rev Clin Immunol ; 20(6): 665-672, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38465507

RESUMO

BACKGROUND: Primary Raynaud's phenomenon (pRP) is difficult to distinguish from secondary (sRP). Although nailfold capillaroscopy (NFC) may detect early alterations, no universal criteria yet discriminate between pRP from sRP. OBJECTIVES: To create and validate two NFC scores that could distinguish pRP from sRP and that could predict systemic sclerosis (SSc), respectively. METHODS: We performed NFC on two separate cohorts with isolated RP, and recorded number of capillaries per field, enlarged/giant capillaries, crossed/bizarre patterns, microhemorrhages, neoangiogenesis, rarefaction, edema, blood flow velocity, stasis. By multivariate regression analysis, we evaluated the adjusted prognostic role of these features in a derivation cohort of 656 patients. Results were used to construct algorithm-based prognostic scores (A and B). These scores were then tested on a confirmation cohort of 219 patients. RESULTS: Score A was unable to discriminate sRP from pRP (low negative predictive values with high positive predictive values for any cut-point); score B was unable to discriminate progression to SSc or a SSc-spectrum disorder (low positive predictive values with high negative predictive values for lower cut-points). CONCLUSION: NFC patterns, believed as specific, showed low discriminatory power and on their own are unable to reliably discriminate sRP from pRP or predict evolution to SSc.


Assuntos
Angioscopia Microscópica , Doença de Raynaud , Escleroderma Sistêmico , Humanos , Doença de Raynaud/diagnóstico , Angioscopia Microscópica/métodos , Feminino , Escleroderma Sistêmico/diagnóstico , Pessoa de Meia-Idade , Masculino , Estudos Prospectivos , Adulto , Prognóstico , Estudos de Coortes , Idoso , Diagnóstico Diferencial , Capilares/diagnóstico por imagem , Capilares/patologia , Unhas/irrigação sanguínea , Unhas/patologia , Valor Preditivo dos Testes
15.
Aesthet Surg J ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470860

RESUMO

BACKGROUND: Polyurethane (PU)-coated breast implants are known for their strong integration into breast tissue and the formation of capsules around them. However, capsular contracture can pose both aesthetic and clinical challenges. OBJECTIVES: To analyze the biological and morphological characteristics of the capsular tissue surrounding PU-coated implants, irrespective of their contracture status, and to assess their potential suitability as a flap in revision breast surgery for capsular contracture. METHODS: A total of 23 tissue samples were harvested from the capsules surrounding PU-coated breast implants in 12 female patients during replacement or revision surgery. We evaluated collagen abundance, cellular and vascular density, inflammation, collagen band types and alignment, synovial metaplasia, capsule thickness, and the expression of inflammatory biomarkers and myofibroblasts using immunohistochemical techniques. Scanning electron microscopy was used to assess implant surface characteristics over time. RESULTS: We found a significant association of capsule contraction with longer implantation durations and greater implant surface roughness (p = 0.018 and p = 0.033, respectively). Synovial metaplasia was significantly more frequent in noncontracted capsules (p = 0.0049). Both capsule types consisted of paucicellular, type I collagen-rich compact fibrous tissue with low vascularization. There was a marked reduction in inflammatory cells within the foreign body granuloma. The expression of inflammatory biomarkers in the capsular tissue was negligible. CONCLUSIONS: Given the reduced levels of inflammatory and vascular components within the dense, fibrous capsular tissue, we consider them to be viable alternatives for use as capsular flaps in revision surgery. This strategy has the potential to mimic the reconstruction achieved with acellular dermal matrix.

16.
Mol Cell ; 84(5): 910-925.e5, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38428434

RESUMO

Chloroplasts contain a dedicated genome that encodes subunits of the photosynthesis machinery. Transcription of photosynthesis genes is predominantly carried out by a plastid-encoded RNA polymerase (PEP), a nearly 1 MDa complex composed of core subunits with homology to eubacterial RNA polymerases (RNAPs) and at least 12 additional chloroplast-specific PEP-associated proteins (PAPs). However, the architecture of this complex and the functions of the PAPs remain unknown. Here, we report the cryo-EM structure of a 19-subunit PEP complex from Sinapis alba (white mustard). The structure reveals that the PEP core resembles prokaryotic and nuclear RNAPs but contains chloroplast-specific features that mediate interactions with the PAPs. The PAPs are unrelated to known transcription factors and arrange around the core in a unique fashion. Their structures suggest potential functions during transcription in the chemical environment of chloroplasts. These results reveal structural insights into chloroplast transcription and provide a framework for understanding photosynthesis gene expression.


Assuntos
RNA Polimerases Dirigidas por DNA , RNA de Cloroplastos , RNA de Cloroplastos/metabolismo , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Plastídeos/genética , Plastídeos/metabolismo , Regulação da Expressão Gênica de Plantas , Transcrição Gênica
17.
Genes (Basel) ; 15(2)2024 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-38397160

RESUMO

The European sardine (Sardina pilchardus, Walbaum 1792) is indisputably a commercially important species. Previous studies using uneven sampling or a limited number of makers have presented sometimes conflicting evidence of the genetic structure of S. pilchardus populations. Here, we show that whole genome data from 108 individuals from 16 sampling areas across 5000 km of the species' distribution range (from the Eastern Mediterranean to the archipelago of Azores) support at least three genetic clusters. One includes individuals from Azores and Madeira, with evidence of substructure separating these two archipelagos in the Atlantic. Another cluster broadly corresponds to the center of the distribution, including the sampling sites around Iberia, separated by the Almeria-Oran front from the third cluster that includes all of the Mediterranean samples, except those from the Alboran Sea. Individuals from the Canary Islands appear to belong to the Mediterranean cluster. This suggests at least two important geographical barriers to gene flow, even though these do not seem complete, with many individuals from around Iberia and the Mediterranean showing some patterns compatible with admixture with other genetic clusters. Genomic regions corresponding to the top outliers of genetic differentiation are located in areas of low recombination indicative that genetic architecture also has a role in shaping population structure. These regions include genes related to otolith formation, a calcium carbonate structure in the inner ear previously used to distinguish S. pilchardus populations. Our results provide a baseline for further characterization of physical and genetic barriers that divide European sardine populations, and information for transnational stock management of this highly exploited species towards sustainable fisheries.


Assuntos
Peixes , Metagenômica , Humanos , Animais , Peixes/genética , Portugal , Genoma/genética , Espanha
18.
J Biol Chem ; 300(4): 105777, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395308

RESUMO

3-mercaptopropionate (3MPA) dioxygenase (MDO) is a mononuclear nonheme iron enzyme that catalyzes the O2-dependent oxidation of thiol-bearing substrates to yield the corresponding sulfinic acid. MDO is a member of the cysteine dioxygenase family of small molecule thiol dioxygenases and thus shares a conserved sequence of active site residues (Serine-155, Histidine-157, and Tyrosine-159), collectively referred to as the SHY-motif. It has been demonstrated that these amino acids directly interact with the mononuclear Fe-site, influencing steady-state catalysis, catalytic efficiency, O2-binding, and substrate coordination. However, the underlying mechanism by which this is accomplished is poorly understood. Here, pulsed electron paramagnetic resonance spectroscopy [1H Mims electron nuclear double resonance spectroscopy] is applied to validate density functional theory computational models for the MDO Fe-site simultaneously coordinated by substrate and nitric oxide (NO), (3MPA/NO)-MDO. The enhanced resolution provided by electron nuclear double resonance spectroscopy allows for direct observation of Fe-bound substrate conformations and H-bond donation from Tyr159 to the Fe-bound NO ligand. Further inclusion of SHY-motif residues within the validated model reveals a distinct channel restricting movement of the Fe-bound NO-ligand. It has been argued that the iron-nitrosyl emulates the structure of potential Fe(III)-superoxide intermediates within the MDO catalytic cycle. While the merit of this assumption remains unconfirmed, the model reported here offers a framework to evaluate oxygen binding at the substrate-bound Fe-site and possible reaction mechanisms. It also underscores the significance of hydrogen bonding interactions within the enzymatic active site.


Assuntos
Domínio Catalítico , Dioxigenases , Modelos Moleculares , Ácido 3-Mercaptopropiônico/química , Catálise , Dioxigenases/química , Dioxigenases/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Ferro/metabolismo , Óxido Nítrico/metabolismo , Oxigênio/metabolismo , Estrutura Terciária de Proteína
19.
bioRxiv ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38370761

RESUMO

Phage therapy is a therapeutic approach to treat multidrug resistant infections that employs lytic bacteriophages (phages) to eliminate bacteria. Despite the abundant evidence for its success as an antimicrobial in Eastern Europe, there is scarce data regarding its effects on the human host. Here, we aimed to understand how lytic phages interact with cells of the airway epithelium, the tissue site that is colonized by bacterial biofilms in numerous chronic respiratory disorders. We determined that interactions between phages and epithelial cells depend on specific phage properties as well as physiochemical features of the microenvironment. Although poor at internalizing phages, the airway epithelium responds to phage exposure by changing its transcriptional profile and secreting antiviral and proinflammatory cytokines that correlate with specific phage families. Overall, our findings indicate that mammalian responses to phages are heterogenous and could potentially alter the way that respiratory local defenses aid in bacterial clearance during phage therapy. Thus, besides phage receptor specificity in a particular bacterial isolate, the criteria to select lytic phages for therapy should be expanded to include mammalian cell responses.

20.
Microb Pathog ; 189: 106596, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395317

RESUMO

Botulism is a severe disease caused by potent botulinum neurotoxins (BoNTs) produced by Clostridium botulinum. This disease is associated with high-lethality outbreaks in cattle, which have been linked to the ingestion of preformed BoNT serotypes C and D, emphasizing the need for effective vaccines. The potency of current commercial toxoids (formaldehyde-inactivated BoNTs) is assured through tests in guinea pigs according to government regulatory guidelines, but their short-term immunity raises concerns. Recombinant vaccines containing the receptor-binding domain have demonstrated potential for eliciting robust protective immunity. Previous studies have demonstrated the safety and effectiveness of recombinant E. coli bacterin, eliciting high titers of neutralizing antibodies against C. botulinum and C. perfringens in target animal species. In this study, neutralizing antibody titers in cattle and the long-term immune response against BoNT/C and D were used to assess the efficacy of the oil-based adjuvant compared with that of the aluminum hydroxide adjuvant in cattle. The vaccine formulation containing Montanide™ ISA 50 yielded significantly higher titers of neutralizing antibody against BoNT/C and D (8.64 IU/mL and 9.6 IU/mL, respectively) and induced an immune response that lasted longer than the response induced by aluminum, extending between 30 and 60 days. This approach represents a straightforward, cost-effective strategy for recombinant E. coli bacterin, enhancing both the magnitude and duration of the immune response to botulism.


Assuntos
Toxinas Botulínicas , Botulismo , Clostridium botulinum , Bovinos , Animais , Cobaias , Botulismo/prevenção & controle , Botulismo/veterinária , Hidróxido de Alumínio , Escherichia coli/genética , Vacinas Bacterianas/genética , Toxinas Botulínicas/genética , Clostridium botulinum/genética , Adjuvantes Imunológicos , Anticorpos Neutralizantes , Imunidade , Anticorpos Antibacterianos
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