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1.
Mol Microbiol ; 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39484742

RESUMO

Previous in vitro works focusing on virulence determinants of the spirochete Leptospira implicated metalloproteinases as putative contributing factors to the pathogenicity of these bacteria. Those proteins have the capacity to degrade extracellular matrix components (ECM) and proteins of host's innate immunity, notably effectors of the complement system. In this study, we gained further knowledge on the role of leptolysin, one of the leptospiral-secreted metalloproteinases, previously described as having a broad substrate specificity. We demonstrated that a proportion of human patients with mild leptospirosis evaluated in the current study produced antibodies that recognize leptolysin, thus indicating that the protease is expressed during host infection. Using recombinant protein and a knockout mutant strain, Manilae leptolysin-, we determined that leptolysin contributes to Leptospira interrogans serum resistance in vitro, likely by proteolysis of complement molecules of the alternative, the classical, the lectin, and the terminal pathways. Furthermore, in a hamster model of infection, the mutant strain retained virulence; however, infected animals had lower bacterial loads in their kidneys. Further studies are necessary to better understand the role and potential redundancy of metalloproteinases on the pathogenicity of this important neglected disease.

2.
Exp Cell Res ; 442(1): 114211, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39147261

RESUMO

Blood vessel growth and osteogenesis in the skeletal system are coupled; however, fundamental aspects of vascular function in osteoblast-to-osteocyte transition remain unclear. Our study demonstrates that vascular smooth muscle cells (VSMCs), but not endothelial cells, are sufficient to drive bone marrow mesenchymal stromal cell-derived osteoblast-to-osteocyte transition via ß-catenin signaling and exosome-mediated communication. We found that VSMC-derived exosomes are loaded with transcripts encoding proteins associated with the osteocyte phenotype and members of the WNT/ß-catenin signaling pathway. In contrast, endothelial cell-derived exosomes facilitated mature osteoblast differentiation by reprogramming the TGFB1 gene family and osteogenic transcription factors osterix (SP7) and RUNX2. Notably, VSMCs express significant levels of tetraspanins (CD9, CD63, and CD81) and drive the intracellular trafficking of exosomes with a lower membrane zeta potential than those from other cells. Additionally, the high ATP content within these exosomes supports mineralization mechanisms, as ATP is a substrate for alkaline phosphatase. Osteocyte function was further validated by RNA sequencing, revealing activity in genes related to intermittent mineralization and sonic hedgehog signaling, alongside a significant increase in TNFSF11 levels. Our findings unveil a novel role of VSMCs in promoting osteoblast-to-osteocyte transition, thus offering new insights into bone biology and homeostasis, as well as in bone-related diseases. Clinically, these insights could pave the way for innovative therapeutic strategies targeting VSMC-derived exosome pathways to treat bone-related disorders such as osteoporosis. By manipulating these signaling pathways, it may be possible to enhance bone regeneration and improve skeletal health in patients with compromised bone structure and function.


Assuntos
Exossomos , Músculo Liso Vascular , Osteoblastos , Osteócitos , Osteogênese , beta Catenina , Osteoblastos/metabolismo , Osteoblastos/citologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/citologia , Exossomos/metabolismo , Animais , beta Catenina/metabolismo , beta Catenina/genética , Osteócitos/metabolismo , Osteócitos/citologia , Camundongos , Osteogênese/genética , Osteogênese/fisiologia , Miócitos de Músculo Liso/metabolismo , Diferenciação Celular , Humanos , Via de Sinalização Wnt , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Células Cultivadas , Transdução de Sinais , Camundongos Endogâmicos C57BL
3.
Exp Cell Res ; : 114311, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39476942

RESUMO

In light of the complex origins of ectopic vascular calcification and its significant health implications, this study offers a comprehensive exploration of the molecular dynamics governing vascular smooth muscle cells (VSMCs). Focusing on epigenetic modulation, we investigate the transition from a contractile to a calcifying phenotype in VSMCs, with an emphasis on understanding the role of SIRT1. For this purpose, a single batch of human aortic SMCs, used at a specified passage number to maintain consistency, was subjected to calcium and phosphate overload for up to 72 hours. Our findings, validated through RT q-PCR, Western blot, immunofluorescence, and DNA methylation analyses, reveal a complex interplay between acetyltransferases and deacetylases during this phenotypic transition. We highlight HAT1A's critical role in histone acetylation regulation and the involvement of HDACs, as evidenced by subcellular localization studies. Moreover, we demonstrate the modulation of SIRT1 expression, a class III deacetylase, during VSMC calcification, underscoring the influence of DNA methylation in this process. Importantly, the study addresses previously unexplored aspects of the dynamic protein expression patterns observed, providing insight into the counterintuitive expressions of key proteins such as Runx2 and osterix. This research underscores the significant impact of epigenetic mechanisms, particularly the modulation of SIRT1, in the transition from a contractile to a calcifying phenotype in VSMCs, offering potential avenues for further exploration in the context of vascular calcification.

4.
Exp Cell Res ; 440(2): 114136, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38909881

RESUMO

Considering the importance of alternative methodologies to animal experimentation, we propose an organoid-based biological model for in vitro blood vessel generation, achieved through co-culturing endothelial and vascular smooth muscle cells (VSMCs). Initially, the organoids underwent comprehensive characterization, revealing VSMCs (α-SMA + cells) at the periphery and endothelial cells (CD31+ cells) at the core. Additionally, ephrin B2 and ephrin B4, genes implicated in arterial and venous formation respectively, were used to validate the obtained organoid. Moreover, the data indicates exclusive HIF-1α expression in VSMCs, identified through various methodologies. Subsequently, we tested the hypothesis that the generated blood vessels have the capacity to modulate the osteogenic phenotype, demonstrating the ability of HIF-1α to promote osteogenic signals, primarily by influencing Runx2 expression. Overall, this study underscores that the methodology employed to create blood vessel organoids establishes an experimental framework capable of producing a 3D culture model of both venous and arterial endothelial tissues. This model effectively guides morphogenesis from mesenchymal stem cells through paracrine signaling, ultimately leading to an osteogenic acquisition phenotype, with the dynamic involvement of HIF-1α.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Músculo Liso Vascular , Miócitos de Músculo Liso , Organoides , Osteogênese , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Osteogênese/genética , Organoides/metabolismo , Organoides/citologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/citologia , Células Cultivadas , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/citologia , Vasos Sanguíneos/crescimento & desenvolvimento , Técnicas de Cocultura/métodos , Diferenciação Celular , Células Endoteliais/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia
5.
J Lipid Res ; 65(7): 100572, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823780

RESUMO

Contrast-enhanced computed tomography offers a nondestructive approach to studying adipose tissue in 3D. Several contrast-enhancing staining agents (CESAs) have been explored, whereof osmium tetroxide (OsO4) is the most popular nowadays. However, due to the toxicity and volatility of the conventional OsO4, alternative CESAs with similar staining properties were desired. Hf-WD 1:2 POM and Hexabrix have proven effective for structural analysis of adipocytes using contrast-enhanced computed tomography but fail to provide chemical information. This study introduces isotonic Lugol's iodine (IL) as an alternative CESA for adipose tissue analysis, comparing its staining potential with Hf-WD 1:2 POM and Hexabrix in murine caudal vertebrae and bovine muscle tissue strips. Single and sequential staining protocols were compared to assess the maximization of information extraction from each sample. The study investigated interactions, distribution, and reactivity of iodine species towards biomolecules using simplified model systems and assesses the potential of the CESA to provide chemical information. (Bio)chemical analyses on whole tissues revealed that differences in adipocyte gray values post-IL staining were associated with chemical distinctions between bovine muscle tissue and murine caudal vertebrae. More specific, a difference in the degree of unsaturation of fatty acids was identified as a likely contributor, though not the sole determinant of gray value differences. This research sheds light on the potential of IL as a CESA, offering both structural and chemical insights into adipose tissue composition.


Assuntos
Tecido Adiposo , Meios de Contraste , Tomografia Computadorizada por Raios X , Animais , Camundongos , Meios de Contraste/química , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/metabolismo , Bovinos , Tomografia Computadorizada por Raios X/métodos , Coloração e Rotulagem/métodos , Adipócitos/citologia , Adipócitos/metabolismo , Camundongos Endogâmicos C57BL
6.
J Am Chem Soc ; 146(39): 27047-27059, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39298277

RESUMO

Revisiting the impact of the first and often deemed trivial postsynthetic step, i.e., a high-temperature oxidative calcination to remove organic templates, increases our understanding of thermal acid site evolution and Al distributions. An unprecedented degree of control over the acidity of high-silica zeolites (SSZ-13) was achieved by using a low-temperature ozonation approach. Fourier transform infrared spectroscopy of adsorbed probe molecules and solid-state NMR spectroscopy reveal the complexity of the thermal evolution of acid sites. Low-temperature activated (ozonated) zeolites maintain the original Brønsted acidity content and high defect content and have virtually no Lewis acidity. They also preserve the "as-made" Al distribution after crystallization and show a clear link between synthesis conditions and divalent cation capacity, as measured with aqueous cobalt ion uptake. The synthesis protocol is found to be the main contributor to Al proximity, yielding record high exchange capacity when ozonated. After conventional calcination at 500-600 °C, however, the presence of water leads to the gradual depletion of Brønsted acid sites, in particular, in small crystals. This work indicates that low-temperature ozonation followed by thermal activation at different temperatures can be used as a novel tool for tuning the amount and nature of acid sites, providing insights into the activity of zeolites in acid-catalyzed reactions, such as CO2 hydrogenation to dimethyl ether, and thereby expanding the possibilities of rational acidity tuning.

7.
Anal Chem ; 96(41): 16469-16474, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39365955

RESUMO

Proton nuclear magnetic resonance (NMR) relaxometry is proposed to determine the iron redox ratio of slag samples. It depends on the paramagnetic effect on bulk water relaxation times. Experiments have been carried out to calibrate the relationship between the concentration of Fe3+ and Fe2+ ions and the measured relaxation times on prepared standard samples. It is shown that Fe2+ ions have very different effects on the relaxation times than Fe3+ ions. For the solid slag samples, digestion in an acid was used to produce solutions with a pH of 1.0. Hydrogen peroxide (H2O2) was then added to the digested samples to oxidize Fe2+ ions to Fe3+ ions. The concentration of Fe2+ and Fe3+ ions in solution can be calculated by measuring the relaxation times before and after oxidation. The Fe3+/∑Fe ratio of slag samples was also investigated by wet chemistry and 57Fe Mössbauer spectroscopy and calculated by FactSage at the equilibrium state. The results obtained from different methods are consistent, indicating that this NMR relaxometry method is reliable.

8.
Cell Biol Int ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591759

RESUMO

During the morphological changes occurring in osteoblast differentiation, Sonic hedgehog (Shh) plays a crucial role. While some progress has been made in understanding this process, the epigenetic mechanisms governing the expression of Hh signaling members in response to bone morphogenetic protein 7 (BMP7) signaling in osteoblasts remain poorly understood. To delve deeper into this issue, we treated pre-osteoblasts (pObs) with 100 ng/mL of BMP7 for up to 21 days. Initially, we validated the osteogenic phenotype by confirming elevated expression of well-defined gene biomarkers, including Runx2, Osterix, Alkaline Phosphatase (Alp), and bone sialoprotein (Bsp). Simultaneously, Hh signaling-related members Sonic (Shh), Indian (Ihh), and Desert (Dhh) Hedgehog (Hh) exhibited nuanced modulation over the 21 days in vitro period. Subsequently, we evaluated epigenetic markers, and our data revealed a notable change in the CpG methylation profile, considering the methylation/hydroxymethylation ratio. CpG methylation is a reversible process regulated by DNA methyltransferases and demethylases, including Ten-eleven translocation (Tets), which also exhibited changes during the acquisition of the osteogenic phenotype. Specifically, we measured the methylation pattern of Shh-related genes and demonstrated a positive Pearson correlation for GLI Family Zinc Finger 1 (Gli1) and Patched (Ptch1). This data underscores the significance of the epigenetic machinery in modulating the BMP7-induced osteogenic phenotype by influencing the activity of Shh-related genes. In conclusion, this study highlights the positive impact of epigenetic control on the expression of genes related to hedgehog signaling during the morphogenetic changes induced by BMP7 signaling in osteoblasts.

9.
Cell Biol Int ; 48(5): 665-681, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38420868

RESUMO

Epigenetic changes, particularly histone compaction modifications, have emerged as critical regulators in the epigenetic pathway driving endothelial cell phenotype under constant exposure to laminar forces induced by blood flow. However, the underlying epigenetic mechanisms governing endothelial cell behavior in this context remain poorly understood. To address this knowledge gap, we conducted in vitro experiments using human umbilical vein endothelial cells subjected to various tensional forces simulating pathophysiological blood flow shear stress conditions, ranging from normotensive to hypertensive forces. Our study uncovers a noteworthy observation wherein endothelial cells exposed to high shear stress demonstrate a decrease in the epigenetic marks H3K4ac and H3K27ac, accompanied by significant alterations in the levels of HDAC (histone deacetylase) proteins. Moreover, we demonstrate a negative regulatory effect of increased shear stress on HOXA13 gene expression and a concomitant increase in the expression of the long noncoding RNA, HOTTIP, suggesting a direct association with the suppression of HOXA13. Collectively, these findings represent the first evidence of the role of histone-related epigenetic modifications in modulating chromatin compaction during mechanosignaling of endothelial cells in response to elevated shear stress forces. Additionally, our results highlight the importance of understanding the physiological role of HOXA13 in vascular biology and hypertensive patients, emphasizing the potential for developing small molecules to modulate its activity. These findings warrant further preclinical investigations and open new avenues for therapeutic interventions targeting epigenetic mechanisms in hypertensive conditions.


Assuntos
Epigênese Genética , Histonas , Humanos , Histonas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Hemodinâmica , Estresse Mecânico , Células Cultivadas
10.
Rapid Commun Mass Spectrom ; 38(12): e9739, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38605205

RESUMO

RATIONALE: 4,7-Dichloroquinoline (DCQ) represents a group of synthetic molecules inspired by natural products with important roles in biological and biomedical areas. This work aimed to characterize DCQ and its derivatives by high-resolution electrospray ionization (ESI) mass spectrometry and tandem mass spectrometry (ESI-MS/MS), supported by theoretical calculations. Biological assays were carried out with DCQ and its derivatives to determine LC50 values against Aedes aegypti larvae. METHODS: Five DCQ derivatives were synthesized by using previously described protocols. ESI-MS/MS analyses were carried out with a quadrupole/time-of-flight and ion-trap instrument. The proposed gas-phase protonation sites and fragmentation were supported by density functional theory calculations. The larvicidal tests were performed with the Ae. aegypti Rockefeller strain, and the LC50 values were determined by employing five test concentrations. Larval mortality was determined after treatment for 48 h. RESULTS: DCQ bromides or aldehydes (C-3 or C-8 positions), as well as the trimethylsilyl derivative (C-3 position), were prepared. Detailed ESI-MS/MS data revealed heteroatom elimination through an exception to the even-electron rule, to originate open-shell species. Computational studies were used to define the protonation sites and fragmentation pathways. High activity of DCQ and its derivatives against Ae. aegypti larvae was demonstrated. CONCLUSION: Our results provided a well-founded characterization of the fragmentation reactions of DCQ and its derivatives, which can be useful for complementary studies of the development of a larvicidal product against Ae. aegypti.


Assuntos
Aedes , Espectrometria de Massas por Ionização por Electrospray , Animais , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Larva
11.
J Med Primatol ; 53(5): e12732, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39160696

RESUMO

BACKGROUND: Marmosets (Callithrix sp.), including black-tuffed marmosets (C. penicillata), are neotropical primates that can be highly adapted to urban environments, especially parks and forested areas near cities. Staphylococcus spp. are part of the microbiota of many different hosts and lead to opportunistic severe infection. Isolates from wild animals can be resistant to antimicrobial drugs. However, there are a few studies that evaluated Staphylococcus spp. in neotropical primates. The goal of this study was to evaluate Staphylococcus spp. isolated from free-ranging black-tuffed marmosets. METHODS: Marmosets were captured in six urban parks. After sedation, skin and rectal swabs and feces were sampled. Staphylococcus spp. isolates were identified by MALDI-ToF and their antimicrobial susceptibility was determined. RESULTS: Over 30% of captured individuals were positive for Staphylococcus spp., and S. aureus was the most isolated species followed by Mammaliicoccus (Staphylococcus) sciuri. With the exception of the marmoset subjected to necropsy, none of the other had lesions, which supports that notion that Staphylococcus spp. are members of the microbiota, but also opportunistic pathogens. Most isolates were susceptible to all antimicrobials tested; however, one isolate of S. epidermidis was resistant to multiple antimicrobials (penicillin, cefoxitin, ciprofloxacin, clindamycin, and erythromycin). We considered S. aureus as the main staphylococci to colonize black-tuffed marmosets. CONCLUSIONS: Black-tuffed marmosets can be colonized by several Staphylococcus species, most frequently by S. aureus, and the majority of isolates were sensible to the antimicrobials tested. One S. epidermidis isolate was considered multidrug resistant.


Assuntos
Antibacterianos , Callithrix , Doenças dos Macacos , Infecções Estafilocócicas , Staphylococcus , Animais , Callithrix/microbiologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/isolamento & purificação , Doenças dos Macacos/microbiologia , Doenças dos Macacos/epidemiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/epidemiologia , Antibacterianos/farmacologia , Feminino , Farmacorresistência Bacteriana , Masculino , Microbiota/efeitos dos fármacos , Cidades , Brasil/epidemiologia , Fezes/microbiologia
12.
Avian Pathol ; 53(5): 408-418, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38662518

RESUMO

Runting and stunting syndrome (RSS) is an enteric viral disease in commercial poultry that directly affects gut health; however, its influence on gut microbiota remains unknown. This study aimed to investigate the compositional changes in the bacterial community of the ileum of 7-day-old broiler chicks naturally affected or not affected by RSS, using next-generation sequencing (NGS) technology. Twenty-one samples were obtained from the ileal contents and mucosa of 11 chicks with RSS and 10 healthy chicks, raised in a dark house system located on a farm in the state of Minas Gerais, Brazil. The results revealed overall changes in the gut microbiota of the chicks with RSS, including a decrease in microbial richness and diversity. In particular, there was a decrease in Lactobacillus and an increase in Candidatus Arthromitus and Clostridium sensu stricto 1. These results indicate a relationship between viral infection and the gut microbial composition, which can cause gut dysbiosis and may influence inflammation in this organ.RESEARCH HIGHLIGHTS RSS causes dysbiosis of the gut microbiota of the ilea of chicks.A difference was found in gut microbiota between chicks with or without RSS.Candidatus Arthromitus was predominant in chicks with RSS.Clostridium sensu stricto 1 was strictly associated with chicks with RSS.


Assuntos
Galinhas , Microbioma Gastrointestinal , Metagenômica , Doenças das Aves Domésticas , Animais , Galinhas/microbiologia , Galinhas/virologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/virologia , Brasil/epidemiologia , Disbiose/veterinária , Disbiose/microbiologia , Íleo/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Transtornos do Crescimento/veterinária , Transtornos do Crescimento/microbiologia , Bactérias/isolamento & purificação , Bactérias/classificação , Bactérias/genética
13.
Epilepsy Behav ; 155: 109800, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657485

RESUMO

Epilepsy is a neurological disease characterized by spontaneous and recurrent seizures. Epileptic seizures can be initiated and facilitated by inflammatory mechanisms. As the dysregulation of the immune system would be involved in epileptogenesis, it is suggested that anti-inflammatory medications could impact epileptic seizures. These medications could potentially have a side effect by altering the structure and composition of the intestinal microbiota. These changes can disrupt microbial homeostasis, leading to dysbiosis and potentially exacerbating intestinal inflammation. We hypothesize that prednisolone may affect the development of epileptic seizures, potentially influencing the diversity of the intestinal microbiota and the regulation of pro-inflammatory cytokines in intestinal tissue. This study aimed to evaluate the effects of prednisolone treatment on epileptic seizures and investigate the effect of this drug on the bacterial diversity of the intestinal microbiota and markers of inflammatory processes in intestinal tissue. We used Male Wistar rat littermates (n = 31, 90-day-old) divided into four groups: positive control treated with 2 mg/kg of diazepam (n = 6), negative control treated with 0.9 g% sodium chloride (n = 6), and the remaining two groups were subjected to treatment with prednisolone, with one receiving 1 mg/kg (n = 9) and the other 5 mg/kg (n = 10). All administrations were performed intraperitoneally (i.p.) over 14 days. To induce the chronic model of epileptic seizures, we administered pentylenetetrazole (PTZ) 25 mg/kg i.p. on alternate days. Seizure latency (n = 6 - 10) and TNF-α and IL-1ß concentrations from intestinal samples were measured by ELISA (n = 6 per group), and intestinal microbiota was evaluated with intergenic ribosomal RNA (rRNA) spacer (RISA) analysis (n = 6 per group). The prednisolone treatment demonstrated an increase in the latency time of epileptic seizures and TNF-α and IL-1ß concentrations compared to controls. There was no statistically significant difference in intestinal microbiota diversity between the different treatments. However, there was a strong positive correlation between microbial diversity and TNF-α and IL-1ß concentrations. The administration of prednisolone yields comparable results to diazepam on increasing latency between seizures, exhibiting promise for its use in clinical studies. Although there were no changes in intestinal microbial diversity, the increase in the TNF-α and IL-1ß cytokines in intestinal tissue may be linked to immune system signaling pathways involving the intestinal microbiota. Additional research is necessary to unravel the intricacies of these pathways and to understand their implications for clinical practice.


Assuntos
Citocinas , Modelos Animais de Doenças , Epilepsia , Microbioma Gastrointestinal , Excitação Neurológica , Prednisolona , Ratos Wistar , Animais , Prednisolona/farmacologia , Prednisolona/uso terapêutico , Masculino , Citocinas/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Excitação Neurológica/efeitos dos fármacos , Ratos , Epilepsia/tratamento farmacológico , Epilepsia/microbiologia , Anti-Inflamatórios/farmacologia
14.
Bioorg Chem ; 146: 107302, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521010

RESUMO

Leishmaniasis, a group of neglected infectious diseases, encompasses a serious health concern, particularly with visceral leishmaniasis exhibiting potentially fatal outcomes. Nucleoside hydrolase (NH) has a fundamental role in the purine salvage pathway, crucial for Leishmania donovani survival, and presents a promising target for developing new drugs for visceral leishmaniasis treatment. In this study, LdNH was immobilized into fused silica capillaries, resulting in immobilized enzyme reactors (IMERs). The LdNH-IMER activity was monitored on-flow in a multidimensional liquid chromatography system, with the IMER in the first dimension. A C18 analytical column in the second dimension furnished the rapid separation of the substrate (inosine) and product (hypoxanthine), enabling direct enzyme activity monitoring through product quantification. LdNH-IMER exhibited high stability and was characterized by determining the Michaelis-Menten constant. A known inhibitor (1-(ß-d-Ribofuranosyl)-4-quinolone derivative) was used as a model to validate the established method in inhibitor recognition. Screening of three additional derivatives of 1-(ß-d-Ribofuranosyl)-4-quinolone led to the discovery of novel inhibitors, with compound 2a exhibiting superior inhibitory activity (Ki = 23.37 ± 3.64 µmol/L) compared to the employed model inhibitor. Docking and Molecular Dynamics studies provided crucial insights into inhibitor interactions at the enzyme active site, offering valuable information for developing new LdNH inhibitors. Therefore, this study presents a novel screening assay and contributes to the development of potent LdNH inhibitors.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Humanos , N-Glicosil Hidrolases/metabolismo , Cromatografia de Afinidade , 4-Quinolonas
15.
Langenbecks Arch Surg ; 409(1): 202, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958771

RESUMO

PURPOSE: We aim to evaluate the impact of surgical wound complications in the first 30 postoperative days after incisional hernia repair on the long-term quality of life of patients. In addition, the impact of the surgical technique and preoperative comorbidities on the quality of life of patients will also be evaluated. METHOD: Prospective cohort study, which evaluates 115 patients who underwent incisional hernioplasty between 2019 and 2020, using the onlay and retromuscular techniques. These patients were initially assessed with regard to surgical wound outcomes in the first 30 postoperative days (surgical site infection (SSI) or surgical site occurrence (SSO)), and then, assessed after three years, through a specific quality of life questionnaire, the Hernia Related Quality of Life Survey (HerQLes). RESULTS: After some patients were lost to follow-up during the study period, due to death, difficulty in contact, refusal to respond to the questionnaire, eighty patients were evaluated. Of these, 11 patients (13.8%) had SSI in the first 30 postoperative days and 37 (46.3%) had some type of SSO. The impact of both SSI and SSO on quality of life indices was not identified. When analyzing others variables, we observed that the Body Mass Index (BMI) had a significant impact on the patients' quality of life. Likewise, hernia size and mesh size were identified as variables related to a worse quality of life outcome. No difference was observed regarding the surgical techniques used. CONCLUSION: In the present study, no relationship was identified between surgical wound outcomes (SSO and SSI) and worse quality of life results using the HerQLes score. We observed that both BMI and the size of meshes and hernias showed an inversely proportional relationship with quality of life indices. However, more studies evaluating preoperative quality of life indices and comparing them with postoperative indices should be carried out to evaluate these correlations.


Assuntos
Herniorrafia , Hérnia Incisional , Qualidade de Vida , Infecção da Ferida Cirúrgica , Cicatrização , Humanos , Feminino , Masculino , Hérnia Incisional/cirurgia , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Cicatrização/fisiologia , Inquéritos e Questionários , Adulto , Telas Cirúrgicas , Estudos de Coortes
16.
Scand J Med Sci Sports ; 34(8): e14712, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39118425

RESUMO

Patellar tendinopathy is more prevalent in males versus female athletes and commonly presents in the medial region of the tendon. Separate measures of patellar tendon strain in the medial, central, and lateral regions of the tendon, however, have not been quantified. The purpose was to investigate the differences in tendon strain between the medial, lateral, and central regions of the patellar tendon in healthy men and women. Strain in the medial and lateral regions of the patellar tendon in healthy participants (10 males, 10 females) was evaluated using ultrasound during isometric quadriceps contractions at 20%, 40%, 60%, 80%, and 100% of maximum voluntary contraction (MVIC) in 60° and 90° of knee flexion. Central strain was also measured at 60% MVIC in 90° of knee flexion. Mixed models were used to determine strain between tendon regions and sex at 60% MVIC in 90° of knee flexion. Sequential modeling was used to fit region, sex, %MVIC, and angle to predict strain. The central region had less strain compared with both medial and lateral regions. The lateral region had higher strain compared with the medial region regardless of sex. Females had higher strain compared with males, regardless of region. Knee position did not influence tendon strain. Patellar tendon strain differs by region and sex. The varying prevalence between sex and in location of patellar tendinopathy may in part be explained by the unbalanced strains. Differential assessment of regional patellar tendon strain may be of importance for understanding injury risk and recovery with exercise.


Assuntos
Ligamento Patelar , Tendinopatia , Ultrassonografia , Humanos , Ligamento Patelar/fisiologia , Ligamento Patelar/diagnóstico por imagem , Masculino , Feminino , Adulto , Adulto Jovem , Fatores Sexuais , Tendinopatia/diagnóstico por imagem , Tendinopatia/fisiopatologia , Músculo Quadríceps/fisiologia , Músculo Quadríceps/diagnóstico por imagem , Contração Isométrica/fisiologia , Fenômenos Biomecânicos
17.
Curr Top Membr ; 94: 247-285, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39370209

RESUMO

Extracellular vesicles (EVs), which include small EVs such as exosomes, play a critical role in intercellular communication and are produced by both cancer and non-cancer cells. Several studies have shown that cancer cells exploit various strategies to regulate the biogenesis, composition, and functions of EVs primarily to promote cancer progression. Given that exosomes originate from major sorting hubs at the limiting membrane of endosomes, they are central to a signaling network that connects external stimuli with intrinsic tumor cell features. Exosomes contain diverse repertoires of molecular cargos, such as proteins, lipids, and nucleic acids, which determine their heterogeneity and functional properties in cancer progression. Therefore, targeting exosome biogenesis will enhance our understanding of tumorigenesis and also promote the discovery of novel approaches for cancer therapy. In this chapter we summarize the machinery of exosome biogenesis and the local, distant, and systemic effects of exosomes released by cancer cells. Furthermore, we explore how these exosomes regulate the anti-tumor immune response and epigenetic mechanisms to sustain cancer progression and their implications in cancer prevention and treatment.


Assuntos
Vesículas Extracelulares , Neoplasias , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Vesículas Extracelulares/metabolismo , Exossomos/metabolismo , Animais , Comunicação Celular
18.
Clin Rehabil ; 38(11): 1466-1480, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39094377

RESUMO

OBJECTIVE: To evaluate the use of custom-made insoles adapted to flip-flops on pain intensity, foot function, and functional walking ability in individuals with persistent plantar heel pain in the short and medium term. DESIGN: Randomised controlled trial. SETTING: Flip-flop sandals in patients with persistent plantar heel pain. MAIN MEASURES: Participants (n = 80) were assessed at baseline, six and 12 weeks after the intervention, and 4 weeks post-intervention. RESULTS: For the primary outcomes, after 6 weeks of intervention, no between-group difference was observed in the intensity of morning pain or pain with walking, mean difference = -0.4 (95% confidence intervals = -1.5 to 0.8). Similarly, after 12 weeks of intervention, no between-group difference was observed in the intensity of morning pain or pain with walking, mean difference = -0.7 (95% confidence intervals = -1.9 to 0.6). Finally, at 4 weeks after the end of the intervention, there was no between-group difference in morning pain or pain on walking, mean difference = 0.01 (95% confidence intervals = -1.4 to 1.4). All differences and confidence intervals were smaller than the minimum clinically important difference for pain (2 points). There were no differences between the groups for the secondary outcomes. In addition, the mean differences were smaller than the minimum clinically important differences for pain intensity, foot function and functional walking ability. CONCLUSION: Custom-made insoles fitted to flip-flops did not differ from flip-flops with sham insoles in improving pain intensity, foot function and functional walking ability in people with persistent heel pain.Trial registration: ClinicalTrials.gov (Identifier: NCT04784598). Data of registration: 2023-01-20.


Assuntos
Órtoses do Pé , Medição da Dor , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Caminhada/fisiologia , Calcanhar , Fasciíte Plantar/terapia , Fasciíte Plantar/reabilitação , Sapatos , Adulto , Desenho de Equipamento , Resultado do Tratamento , Idoso , Manejo da Dor/métodos
19.
Magn Reson Chem ; 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39474662

RESUMO

The removal of heavy metal ions from wastewater often necessitates the use of ion exchange resins. Current methods for assessing ion exchange efficiency are indirect and destructive. Some heavy metal ions, such as Cu2+ and Ni2+, are paramagnetic and influence the NMR relaxation times of water protons. NMR relaxometry can therefore be utilized to track the removal of these ions by ion exchange resins. In this study, we use relaxometry to monitor in situ the loading with Ni2+ and Cu2+ of Amberlite IR120 and Dowex Marathon MSC resins, with the resin column inserted into a low-field NMR device. The multiexponential transverse relaxation curves were fitted using a biexponential model. Before and during the loading of the resin, the water with the slowest relaxation corresponds to treated water (free of Ni2+ or Cu2+) flowing between the resin beads. After saturation, the slowest fraction corresponds to the untreated solution (containing Ni2+ or Cu2+) flowing between the resin beads saturated with paramagnetic ions. The evolution with time of the transverse relaxation rate and the amplitude of the slowly relaxing water fraction shows a clear transition, occurring later at the bottom of the resin bed compared with the middle and top. This is interpreted as an indication of the saturation of the studied zone with paramagnetic ions, confirmed by the quantification of Ni2+ or Cu2+ in the effluent using AES spectroscopy. This proof-of-concept study demonstrates that NMR relaxometry can be used in situ to monitor the loading of a resin bed with paramagnetic ions.

20.
Lasers Med Sci ; 39(1): 110, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649644

RESUMO

The sample comprised 44 volunteers who had undergone some surgical procedure and were equally divided into four groups. G1 started the therapy 24 h after the surgical procedure with the device off. G2 followed the same time pattern, 24 h, but with the device turned on. G3 and G4 started therapy three days after the surgical procedure; in G3, the device was turned off, and in G4, the device remained on during therapy; each session lasted 30 min, using 660 nm (red), energy 180 J. For all groups, the therapy started with daily use for seven days and followed the interval use of three times a week until completed 21 days. The revaluation was performed after 7 and 21 days. The results found show changes in HR at rest, systolic and diastolic BP, and in peripheral oxygen saturation, which showed a significant difference in the groups that used on-therapy (p < 0.05). In the MCGILL Scale evaluation, the mean total score showed a more accentuated drop in the groups that used ILIB, (p < 0.05). ILIB may have prevented a more significant evolution of firosis levels; however, no changes were observed in the evaluation of sleep and anxiety. The application of the ILIB in patients undergoing plastic surgery was supported in terms of hemodynamics and pain; in addition, starting the ILIB application 24 h after the procedure proved to be more advantageous.


Assuntos
Procedimentos de Cirurgia Plástica , Humanos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Técnica de Ilizarov/instrumentação , Hemodinâmica , Adulto Jovem , Saturação de Oxigênio , Cirurgia Plástica/métodos
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