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2.
Int J Mol Sci ; 25(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39273417

RESUMO

To explore new compounds with antitumour activity, fifteen phenolic nor-tripterpenes isolated from Celastraceae species, Maytenus jelskii, Maytenus cuzcoina, and Celastrus vulcanicola, have been studied. Their chemical structures were elucidated through spectroscopic and spectrometric techniques, resulting in the identification of three novel chemical compounds. Evaluation on human tumour cell lines (A549 and SW1573, non-small cell lung; HBL-100 and T-47D, breast; HeLa, cervix, and WiDr, colon) revealed that three compounds, named 6-oxo-pristimerol, demethyl-zeylasteral, and zeylasteral, exhibited significant activity (GI50 ranging from 0.45 to 8.6 µM) on at least five of the cell lines tested. Continuous live cell imaging identified apoptosis as the mode of action of selective cell killing in HeLa cells. Furthermore, their effect on a drug-sensitive Saccharomyces cerevisiae strain has been investigated to deepen on their mechanism of action. In dose-response growth curves, zeylasteral and 7α-hydroxy-blepharodol were markedly active. Additionally, halo assays were conducted to assess the involvement of oxidative stress and/or mitochondrial function in the anticancer profile, ruling out these modes of action for the active compounds. Finally, we also delve into the structure-activity relationship, providing insights into how the molecular structure of these compounds influences their biological activity. This comprehensive analysis enhances our understanding of the therapeutic potential of this triterpene type and underscores its relevance for further research in this field.


Assuntos
Antineoplásicos Fitogênicos , Apoptose , Humanos , Apoptose/efeitos dos fármacos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Fenóis/farmacologia , Fenóis/química , Triterpenos/farmacologia , Triterpenos/química , Células HeLa , Celastraceae/química , Linhagem Celular Tumoral , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Saccharomyces cerevisiae/efeitos dos fármacos , Células A549 , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos
3.
J Nucl Med ; 65(10): 1540-1547, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39237347

RESUMO

Understanding which patients with human epidermal growth factor receptor 2 (HER2)-negative or -low metastatic breast cancer (MBC) benefit from HER2-targeted strategies is urgently needed. We assessed the whole-body heterogeneity of HER2 expression on 89Zr-trastuzumab PET (HER2 PET) and the diagnostic performance of HER2 PET in a large series of patients, including HER2-negative and -low MBC. Methods: In the IMPACT-MBC study, patients with newly diagnosed and nonrapidly progressive MBC of all subtypes were included. Metastasis HER2 status was determined by immunohistochemistry and in situ hybridization.89Zr-trastuzumab uptake was quantified as SUVmax and SUVmean HER2 immunohistochemistry was related to the quantitative 89Zr-trastuzumab uptake of all metastases and corresponding biopsied metastasis, uptake heterogeneity, and qualitative scan evaluation. A prediction algorithm for HER2 immunohistochemistry positivity based on uptake was developed. Results: In 200 patients, 89Zr-trastuzumab uptake was quantified in 5,163 metastases, including 186 biopsied metastases. With increasing HER2 immunohistochemistry status, uptake was higher (geometric mean SUVmax of 7.0, 7.6, 7.3, and 17.4 for a HER2 immunohistochemistry score of 0, 1, 2, or 3+, respectively; P < 0.001). High uptake exceeding 14.6 (90th percentile) was observed in one third of patients with a HER2-negative or -low metastasis biopsy. The algorithm performed best when lesion site and size were incorporated (area under the curve, 0.86; 95% CI, 0.79-0.93). Conclusion: HER2 PET had good diagnostic performance in MBC, showing considerable whole-body HER2 heterogeneity and uptake above background in HER2-negative and -low MBC. This provides novel insights into HER2-negative and -low MBC compared with standard HER2 immunohistochemistry on a single biopsy.


Assuntos
Neoplasias da Mama , Metástase Neoplásica , Tomografia por Emissão de Pósitrons , Receptor ErbB-2 , Humanos , Receptor ErbB-2/metabolismo , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Imagem Corporal Total , Anticorpos Monoclonais Humanizados
4.
Anaerobe ; 89: 102896, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39127403

RESUMO

INTRODUCTION: Clostridioides difficile is the main cause of antibiotic-associated diarrhea in humans and is a major enteropathogen in several animal species. In newborn piglets, colonic lesions caused by C. difficile A and B toxins (TcdA and TcdB, respectively) cause diarrhea and significant production losses. OBJECTIVE: The present study aimed to develop two recombinant vaccines from immunogenic C-terminal fragments of TcdA and TcdB and evaluate the immune response in rabbits and in breeding sows. Two vaccines were produced: bivalent (rAB), consisting of recombinant fragments of TcdA and TcdB, and chimeric (rQAB), corresponding to the synthesis of the same fragments in a single protein. Groups of rabbits were inoculated with 10 or 50 µg of proteins adjuvanted with aluminum or 0.85 % sterile saline in a final volume of 1 mL/dose. Anti-TcdA and anti-TcdB IgG antibodies were detected in rabbits and sows immunized with both rAB and rQAB vaccines by ELISA. The vaccinated sows were inoculated intramuscularly with 20 µg/dose using a prime-boost approach. RESULTS: Different antibody titers (p ≤ 0.05) were observed among the vaccinated groups of sows (rAB and rQAB) and control. Additionally, newborn piglets from vaccinated sows were also positive for anti-TcdA and anti-TcdB IgGs, in contrast to control piglets (p ≤ 0.05). Immunization of sows with the rQAB vaccine conferred higher anti-TcdA and anti-TcdB responses in piglets, suggesting the superiority of this compound over rAB. CONCLUSION: The synthesized recombinant proteins were capable of inducing antibody titers against C. difficile toxins A and B in sows, and were passively transferred to piglets through colostrum.


Assuntos
Animais Recém-Nascidos , Anticorpos Antibacterianos , Toxinas Bacterianas , Vacinas Bacterianas , Clostridioides difficile , Infecções por Clostridium , Doenças dos Suínos , Vacinas Sintéticas , Animais , Feminino , Suínos , Coelhos , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Infecções por Clostridium/imunologia , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Gravidez , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Clostridioides difficile/imunologia , Clostridioides difficile/genética , Anticorpos Antibacterianos/sangue , Toxinas Bacterianas/imunologia , Toxinas Bacterianas/genética , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética , Enterotoxinas/imunologia , Enterotoxinas/genética
5.
J Phys Chem B ; 128(27): 6476-6491, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38951498

RESUMO

The chimeric oncoprotein Bcr-Abl is the causative agent of virtually all chronic myeloid leukemias and a subset of acute lymphoblastic leukemias. As a result of the so-called Philadelphia chromosome translocation t(9;22), Bcr-Abl manifests as a constitutively active tyrosine kinase, which promotes leukemogenesis by activation of cell cycle signaling pathways. Constitutive and oncogenic activation is mediated by an N-terminal coiled-coil oligomerization domain in Bcr (Bcr-CC), presenting a therapeutic target for inhibition of Bcr-Abl activity toward the treatment of Bcr-Abl+ leukemias. Previously, we demonstrated that a rationally designed Bcr-CC mutant, CCmut3, exerts a dominant negative effect upon Bcr-Abl activity by preferential oligomerization with Bcr-CC. Moreover, we have shown that conjugation to a leukemia-specific cell-penetrating peptide (CPP-CCmut3) improves intracellular delivery and activity. However, our full-length CPP-CCmut3 construct (81 aa) is encumbered by an intrinsically high degree of conformational variability and susceptibility to proteolytic degradation relative to traditional small-molecule therapeutics. Here, we iterate a new generation of CCmut3 inhibitors against Bcr-CC-mediated Bcr-Abl assembly designed to address these constraints through incorporation of all-hydrocarbon staples spanning i and i + 7 positions in α-helix 2 (CPP-CCmut3-st). We utilize computational modeling and biomolecular simulation to evaluate single- and double-stapled CCmut3 candidates in silico for dynamics and binding energetics. We further model a truncated system characterized by the deletion of α-helix 1 and the flexible loop linker, which are known to impart high conformational variability. To study the impact of the N-terminal cyclic CPP toward model stability and inhibitor activity, we also model the full-length and truncated systems devoid of the CPP, with a cyclized CPP, and with an open-configuration CPP, for a total of six systems that comprise our library. From this library, we present lead-stapled peptide candidates to be synthesized and evaluated experimentally as our next iteration of inhibitors against Bcr-Abl.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/metabolismo , Proteínas de Fusão bcr-abl/química , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Humanos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/metabolismo , Modelos Moleculares , Simulação de Dinâmica Molecular , Antineoplásicos/química , Antineoplásicos/farmacologia , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/farmacologia , Peptídeos Penetradores de Células/metabolismo
6.
Commun Biol ; 7(1): 839, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987278

RESUMO

Clostridioides difficile causes a wide range of intestinal diseases through the action of two main cytotoxins, TcdA and TcdB. Ingested spores germinate in the intestine establishing a population of cells that produce toxins and spores. The pathogenicity locus, PaLoc, comprises several genes, including those coding for TcdA/B, for the holin-like TcdE protein, and for TcdR, an auto-regulatory RNA polymerase sigma factor essential for tcdA/B and tcdE expression. Here we show that tcdR, tcdA, tcdB and tcdE are expressed in a fraction of the sporulating cells, in either the whole sporangium or in the forespore. The whole sporangium pattern is due to protracted expression initiated in vegetative cells by σD, which primes the TcdR auto-regulatory loop. In contrast, the forespore-specific regulatory proteins σG and SpoVT control TcdR production and tcdA/tcdB and tcdE expression in this cell. We detected TcdA at the spore surface, and we show that wild type and ΔtcdA or ΔtcdB spores but not ΔtcdR or ΔtcdA/ΔtcdB spores are cytopathic against HT29 and Vero cells, indicating that spores may serve as toxin-delivery vehicles. Since the addition of TcdA and TcdB enhance binding of spores to epithelial cells, this effect may occur independently of toxin production by vegetative cells.


Assuntos
Toxinas Bacterianas , Clostridioides difficile , Esporos Bacterianos , Esporos Bacterianos/metabolismo , Esporos Bacterianos/genética , Clostridioides difficile/genética , Clostridioides difficile/metabolismo , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/genética , Humanos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Animais , Chlorocebus aethiops , Células Vero , Enterotoxinas/metabolismo , Enterotoxinas/genética
7.
J Glob Antimicrob Resist ; 38: 227-230, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39004340

RESUMO

OBJECTIVES: To investigate the tet(X) gene, a determinant of tigecycline resistance, in the emerging pathogen Elizabethkingia meningoseptica and its association with an integrative and conjugative element (ICE). METHODS: All E. meningoseptica genomes from the National Center for Biotechnology Information (n = 87) were retrieved and annotated for resistome searches using the CARD database. A phylogenic analysis was performed based on the E. meningoseptica core genome. The ICE was identified through comparative genomics with other ICEs occurring in Elizabethkingia spp. RESULTS: Phylogenetic analysis revealed E. meningoseptica genomes from six countries distributed across different lineages, some of which persisted for years. The common resistome of these genomes included blaBlaB, blaCME, blaGOB, ranA/B, aadS, and catB (genes associated with resistance to ß-lactams, aminoglycosides, and chloramphenicol). Some genomes also presented additional resistance genes (dfrA, ereD, blaVEB, aadS, and tet(X)). Interestingly, tet(X) and aadS were located in an ICE of 49 769 bp (ICEEmSQ101), which was fully obtained from the E. meningoseptica SQ101 genome. We also showed evidence that the other 27 genomes harboured this ICE. The distribution of ICEEmSQ101, carrying tet(X), was restricted to a single Chinese lineage. CONCLUSIONS: The tet(X) gene is not prevalent in the species E. meningoseptica, as previously stated for the genus Elizabethkingia, since it is present only in a single Chinese lineage. We identified that several E. meningoseptica genomes harboured an ICE that mobilized the Elizabethkingia tet(X) gene and exhibited characteristics similar to the ICEs of other Flavobacteria, which would favour their transmission in this bacterial family.


Assuntos
Antibacterianos , Infecções por Flavobacteriaceae , Flavobacteriaceae , Genoma Bacteriano , Filogenia , Antibacterianos/farmacologia , Infecções por Flavobacteriaceae/microbiologia , Flavobacteriaceae/genética , Flavobacteriaceae/efeitos dos fármacos , Flavobacteriaceae/classificação , Humanos , Testes de Sensibilidade Microbiana , Tigeciclina/farmacologia , Conjugação Genética , Prevalência , Farmacorresistência Bacteriana/genética
8.
Zookeys ; 1202: 213-228, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38826493

RESUMO

In the subfamily Triatominae, the genus Rhodnius is one of the most studied, not only because of its epidemiological importance, but also because of the difficulty in differentiating its species. Currently, one of the strategies to control Chagas disease, besides other initiatives such as the analysis of donated blood, is focused on fighting the vector. Correctly identifying triatomines is essential for the entomoepidemiological surveillance of Chagas disease. The objective of the present work was to compare the species of the R.prolixus complex using geometric morphometry of hemelytra and heads to evaluate the patterns of intraspecific and interspecific allometry and their taxonomic implications. This method can help in the diagnosis of close species, whose morphological characteristics are insufficient for correct identification. Specimens from five different collections were used, covering the species included in the R.prolixus complex (R.barretti, R.dalessandroi, R.domesticus, R.marabaensis, R.milesi, R.montenegrensis, R.nasutus, R.neglectus, R.neivai, R.prolixus and R.robustus). Morphometric analyses indicated that the hemelytra are not structures with good resolution for separating species and, for this reason, the use of the heads proved to be more adequate for this group (thus allowing differentiation of all species of the R.prolixus complex). The results suggest that R.milesi is a variant of R.neglectus and confirms that R.prolixus and R.robustus are distinct species. Furthermore, we propose the creation of the R.neivai complex comprising R.domesticus and R.neivai.

9.
Pestic Biochem Physiol ; 202: 105921, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879297

RESUMO

The evolution of resistance to insecticides poses a significant threat to pest management programs. Understanding the molecular mechanisms underlying insecticide resistance is essential to design sustainable pest control and resistance management programs. The fall armyworm, Spodoptera frugiperda, is an important insect pest of many crops and has a remarkable ability to evolve resistance to insecticides. In this study, we employed bulk segregant analysis (BSA) combined with DNA and RNA sequencing to characterize the molecular basis of spinetoram resistance in S. frugiperda. Analysis of genomic data derived from spinetoram selected and unselected bulks and the spinetoram-resistant and susceptible parental strains led to the identification of a three-nucleotide deletion in the gene encoding the nicotinic acetylcholine receptor α6 subunit (nAChR α6). Transcriptome profiling identified the upregulation of few genes encoding detoxification enzymes associated with spinetoram resistance. Thus, spinetoram resistance in S. frugiperda appears to be mediated mainly by target site insensitivity with a minor role of detoxification enzymes. Our findings provide insight into the mechanisms underpinning resistance to spinetoram in S. frugiperda and will inform the development of strategies to control this highly damaging, globally distributed crop pest.


Assuntos
Resistência a Inseticidas , Inseticidas , Spodoptera , Animais , Spodoptera/genética , Spodoptera/efeitos dos fármacos , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Inseticidas/toxicidade , Perfilação da Expressão Gênica , Transcriptoma , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Macrolídeos
10.
J Glaucoma ; 33(9): 658-664, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38747721

RESUMO

PRCIS: In this meta-analysis of 6 studies and 5269 patients, deep learning algorithms applied to AS-OCT demonstrated excellent diagnostic performance for closed angle compared with gonioscopy, with a pooled sensitivity and specificity of 94% and 93.6%, respectively. PURPOSE: This study aimed to review the literature and compare the accuracy of deep learning algorithms (DLA) applied to anterior segment optical coherence tomography images (AS-OCT) against gonioscopy in detecting angle closure in patients with glaucoma. METHODS: We performed a systematic review and meta-analysis evaluating DLA in AS-OCT images for the diagnosis of angle closure compared with gonioscopic evaluation. PubMed, Scopus, Embase, Lilacs, Scielo, and Cochrane Central Register of Controlled Trials were searched. The bivariate model was used to calculate pooled sensitivity and specificity. RESULTS: The initial search identified 214 studies, of which 6 were included for final analysis. The total study population included 5269 patients. The combined sensitivity of the DLA compared with gonioscopy was 94.0% (95% CI: 83.8%-97.9%), whereas the pooled specificity was 93.6% (95% CI: 85.7%-97.3%). Sensitivity analyses removing each individual study showed a pooled sensitivity in the range of 90.1%-95.1%. Similarly, specificity results ranged from 90.3% to 94.5% with the removal of each individual study and recalculation of pooled specificity. CONCLUSION: DLA applied to AS-OCT has excellent sensitivity and specificity in the identification of angle closure. This technology may be a valuable resource in the screening of populations without access to experienced ophthalmologists who perform gonioscopy.


Assuntos
Câmara Anterior , Inteligência Artificial , Glaucoma de Ângulo Fechado , Gonioscopia , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Câmara Anterior/diagnóstico por imagem , Câmara Anterior/patologia , Glaucoma de Ângulo Fechado/diagnóstico , Glaucoma de Ângulo Fechado/fisiopatologia , Aprendizado Profundo , Sensibilidade e Especificidade , Pressão Intraocular/fisiologia , Algoritmos
11.
Front Oncol ; 14: 1348118, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800378

RESUMO

Objectives: Bisphosphonates (BFs) show clinical effectiveness in managing osteoporosis and bone metastases but pose risks of bisphosphonate-related jaw osteonecrosis (BRONJ). With no established gold standard for BRONJ treatment, our focus is on symptom severity reduction. We aimed to assess the preventive effects of bioactive glass and/or pericardial membrane in a preclinical BRONJ model, evaluating their potential to prevent osteonecrosis and bone loss post-tooth extractions in zoledronic acid (ZA)-treated animals. Methods: Rats, receiving ZA or saline biweekly for four weeks, underwent 1st and 2nd lower left molar extractions. Pericardial membrane alone or with F18 bioglass was applied post-extractions. Microarchitecture analysis and bone loss assessment utilized computerized microtomography (CT) and positron emission tomography (PET) with 18F-FDG and 18F-NaF tracers. Histological analysis evaluated bone injury. Results: Exclusive alveolar bone loss occurred post-extraction in the continuous ZA group, inducing osteonecrosis, osteolysis, osteomyelitis, and abscess formation. Concurrent pericardial membrane with F18 bioglass application prevented these outcomes. Baseline PET/CT scans showed no discernible uptake differences, but post-extraction 18F-FDG tracer imaging revealed heightened glucose metabolism at the extraction site in the ZA-treated group with membrane, contrasting the control group. Conclusion: These findings suggest pericardial membrane with F18 bioglass effectively prevents BRONJ in the preclinical model.

12.
Front Immunol ; 15: 1339318, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711496

RESUMO

Allogeneic Hematopoietic Stem Cell Transplantation (allo-HSCT) is the only curative therapy for many hematologic malignancies, whereby the Graft-versus-Leukemia (GVL) effect plays a pivotal role in controlling relapse. However, the success of GVL is hindered by Graft-versus-Host Disease (GVHD), where donor T cells attack healthy tissues in the recipient. The ability of natural regulatory T cells (Treg) to suppress immune responses has been exploited as a therapeutical option against GVHD. Still, it is crucial to evaluate if the ability of Treg to suppress GVHD does not compromise the benefits of GVL. Initial studies in animal models suggest that Treg can attenuate GVHD while preserving GVL, but results vary according to tumor type. Human trials using Treg as GVHD prophylaxis or treatment show promising results, emphasizing the importance of infusion timing and Treg/Tcon ratios. In this review, we discuss strategies that can be used aiming to enhance GVL post-Treg infusion and the proposed mechanisms for the maintenance of the GVL effect upon the adoptive Treg transfer. In order to optimize the therapeutic outcomes of Treg administration in allo-HSCT, future efforts should focus on refining Treg sources for infusion and evaluating their specificity for antigens mediating GVHD while preserving GVL responses.


Assuntos
Doença Enxerto-Hospedeiro , Efeito Enxerto vs Leucemia , Transplante de Células-Tronco Hematopoéticas , Linfócitos T Reguladores , Linfócitos T Reguladores/imunologia , Humanos , Efeito Enxerto vs Leucemia/imunologia , Animais , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante Homólogo , Transferência Adotiva/métodos , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/imunologia
14.
Brain Commun ; 6(3): fcae093, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707711

RESUMO

Deep brain stimulation has revolutionized the treatment of movement disorders and is gaining momentum in the treatment of several other neuropsychiatric disorders. In almost all applications of this therapy, the insertion of electrodes into the target has been shown to induce some degree of clinical improvement prior to stimulation onset. Disregarding this phenomenon, commonly referred to as 'insertional effect', can lead to biased results in clinical trials, as patients receiving sham stimulation may still experience some degree of symptom amelioration. Similar to the clinical scenario, an improvement in behavioural performance following electrode implantation has also been reported in preclinical models. From a neurohistopathologic perspective, the insertion of electrodes into the brain causes an initial trauma and inflammatory response, the activation of astrocytes, a focal release of gliotransmitters, the hyperexcitability of neurons in the vicinity of the implants, as well as neuroplastic and circuitry changes at a distance from the target. Taken together, it would appear that electrode insertion is not an inert process, but rather triggers a cascade of biological processes, and, as such, should be considered alongside the active delivery of stimulation as an active part of the deep brain stimulation therapy.

15.
Reprod Toxicol ; 126: 108584, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38561096

RESUMO

In the domain of medical advancement, nanotechnology plays a pivotal role, especially in the synthesis of biocompatible materials for therapeutic use. Superparamagnetic Iron Oxide Nanoparticles (SPIONs), known for their magnetic properties and low toxicity, stand at the forefront of this innovation. This study explored the reproductive toxicological effects of Sodium Citrate-functionalized SPIONs (Cit_SPIONs) in adult male mice, an area of research that holds significant potential yet remains largely unknown. Our findings reveal that Cit_SPIONs induce notable morphological changes in interstitial cells and the seminiferous epithelium when introduced via intratesticular injection. This observation is critical in understanding the interactions of nanomaterials within reproductive biological systems. A striking feature of this study is the rapid localization of Cit_SPIONs in Leydig cells post-injection, a factor that appears to be closely linked with the observed decrease in steroidogenic activity and testosterone levels. This data suggests a possible application in developing nanostructured therapies targeting androgen-related processes. Over 56 days, these nanoparticles exhibited remarkable biological distribution in testis parenchyma, infiltrating various cells within the tubular and intertubular compartments. While the duration of spermatogenesis remained unchanged, there were many Tunel-positive germ cells, a notable reduction in daily sperm production, and reduced progressive sperm motility in the treated group. These insights not only shed light on the intricate mechanisms of Cit_SPIONs interaction with the male reproductive system but also highlight the potential of nanotechnology in developing advanced biomedical applications.


Assuntos
Células Intersticiais do Testículo , Nanopartículas Magnéticas de Óxido de Ferro , Espermatogênese , Espermatozoides , Testículo , Testosterona , Animais , Masculino , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro/toxicidade , Testículo/efeitos dos fármacos , Testículo/metabolismo , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Camundongos , Citrato de Sódio/toxicidade
16.
J Sport Rehabil ; 33(5): 325-332, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38688463

RESUMO

CONTEXT: Sports-related concussions are commonly occurring injuries as a result of sports and recreation that may cause alterations in brain functioning. It is important to be able to evaluate the impact of these injuries on function to manage the injury recovery and ensure recovery. Recent literature suggests the use of objective evaluation strategies in a multifaceted approach to evaluate and manage these injuries. It is important to understand the relationships between the assessments and how best to utilize each assessment. The purpose of this study was to investigate if relationships exist between measures of vestibular function at baseline in assessments that may be used following sports-related concussions. Additionally, a secondary purpose was to determine if self-reported symptoms were related to performance on the assessments. This study aimed to identify if these assessments measured independent functions of the vestibulo-ocular reflex or if some redundancy existed among the assessment strategies. DESIGN: A cross-sectional study design was used in a cohort of collegiate athletes ages 18-24. METHODS: Participants completed demographics questionnaires, the Post-Concussion Symptom Scale, Gaze Stabilization Test, and Concussion Balance Test. Spearman rho correlations were used to examine the relationships between the measures. RESULTS: One hundred and thirty-five collegiate athletes (82 males and 53 females) were included, representative of 3 sports (cheerleading, soccer, and football) with a mean age of 19.77 (1.42) years old. There were weak to moderate, significant relationships between measures of Gaze Stabilization Test and Concussion Balance Test errors (r = .20-.31, P = .001-.03). CONCLUSIONS: The direction of these relationships indicated that greater Concussion Balance Test errors were associated with greater Gaze Stabilization Test performance. These relationships may be attributed to the difficulty created by the foam conditions and the integration of more complex sensory tasks required to maintain balance during the more difficult conditions.


Assuntos
Atletas , Traumatismos em Atletas , Concussão Encefálica , Equilíbrio Postural , Humanos , Masculino , Concussão Encefálica/fisiopatologia , Concussão Encefálica/diagnóstico , Feminino , Equilíbrio Postural/fisiologia , Adulto Jovem , Estudos Transversais , Traumatismos em Atletas/fisiopatologia , Adolescente , Reflexo Vestíbulo-Ocular/fisiologia , Universidades
17.
J Sport Rehabil ; : 1-9, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508176

RESUMO

CONTEXT: Concussion evaluations include a multifaceted approach; however, individual differences can influence test score interpretations and validity. Social determinants of health (SDoH) differentially affect disease risk and outcomes based upon social and environmental characteristics. Efforts to better define, diagnose, manage, and treat concussion have increased, but minimal efforts have focused on examining SDoH that may affect concussion recovery. OBJECTIVE: This review examined previous research that examined the effect of SDoH on concussion recovery of athletes. EVIDENCE ACQUISITION: CINAHL, MEDLINE, PsycInfo, and SPORTDiscus databases were used to search the terms "concussion" AND "recovery," "youth, adolescent, teen and/or adult," and "social determinants of health" and variations of these terms. The evidence level for each study was evaluated using the 2011 Oxford Center for Evidence-Based Medicine Guide. EVIDENCE SYNTHESIS: Seven thousand nine hundred and twenty-one articles were identified and screened for inclusion. Five studies met the inclusion criteria and were included in this systematic review. Using the Downs and Black Quality Index, the studies included in this review were deemed high quality. CONCLUSION: Though limited literature exists, there is preliminary evidence to suggest that SDoH (specifically, economic stability, education access and quality, and social and community context) may have an impact on the clinical recovery from concussion. The dimensions evaluated varied between studies and the results were inconsistent. No single factor consistently affected clinical recovery; however, private insurance and race appear to have an association with the speed of recovery. Unfortunately, the potential intersection of these variables and other preinjury factors limits the ability to make clear recommendations. While most of the studies in this review are retrospective in nature, future efforts should focus on training clinicians to prospectively evaluate the effect of SDoH on concussion recovery and injury outcomes. Funding and registration for this systematic review were not obtained nor required.

18.
Behav Brain Res ; 465: 114956, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38479475

RESUMO

Epilepsy designates a group of chronic brain disorders, characterized by the recurrence of hypersynchronous, repetitive activity, of neuronal clusters. Epileptic seizures are the hallmark of epilepsy. The primary goal of epilepsy treatment is to eliminate seizures with minimal side effects. Nevertheless, approximately 30% of patients do not respond to the available drugs. An imbalance between excitatory/inhibitory neurotransmission, that leads to excitotoxicity, seizures, and cell death, has been proposed as an important mechanism regarding epileptogenesis. Recently, it has been shown that microreactors composed of platinum nanoparticles (Pt-NP) and glutamate dehydrogenase possess in vitro and in vivo activity against excitotoxicity. This study investigates the in vivo effects of these microreactors in an animal model of epilepsy induced by the administration of the GABAergic antagonist bicuculline. Male Wistar rats were administered intracerebroventricularly (i.c.v.) with the microreactors or saline and, five days later, injected with bicuculline or saline. Seizure severity was evaluated in an open field. Thirty min after behavioral measurements, animals were euthanized, and their brains processed for neurodegeneration evaluation and for neurogenesis. Treatment with the microreactors significantly increased the time taken for the onset of seizures and for the first tonic-clonic seizure, when compared to the bicuculline group that did not receive the microreactor. The administration of the microreactors also increased the time spent in total exploration and grooming. Treatment with the microreactors decreased bicuculline-induced neurodegeneration and increased neurogenesis in the dorsal and ventral hippocampus. These observations suggest that treatment with Pt-NP-based microreactors attenuates the behavioral and neurobiological consequences of epileptiform seizure activity.


Assuntos
Epilepsia , Nanopartículas Metálicas , Fármacos Neuroprotetores , Humanos , Ratos , Animais , Masculino , Bicuculina/farmacologia , Platina/efeitos adversos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico
19.
Neurosurgery ; 95(3): 509-516, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38511957

RESUMO

Deep brain stimulation (DBS) is an emerging therapy for treatment-resistant depression (TRD). Although adverse effects have been reported in early-phase and a few randomized clinical trials, little is known about its overall safety profile, which has been assumed to be similar to that of DBS for movement disorders. The objective of this study was to pool existing safety data on DBS for TRD. Following PRISMA guidelines, PubMed was searched for English articles describing adverse outcomes after DBS for TRD. Studies were included if they reported at least 5 patients with a minimal follow-up of 6 months. After abstract (n = 607) and full-article review (n = 127), 28 articles reporting on 353 patients met criteria for final inclusion. Follow-up of the studies retrieved ranged from 12 to 96 months. Hemorrhages occurred in 0.8% of patients and infections in 10.2%. The rate of completed suicide was 2.5%. Development or worsening of depressive symptoms, anxiety, and mania occurred in 18.4%, 9.1%, and 5.1%, respectively. There were some differences between targets, but between-study heterogeneity precluded statistical comparisons. In conclusion, DBS for TRD is associated with surgical and psychiatric adverse events. Hemorrhage and infection occur at rates within an accepted range for other DBS applications. The risk of suicide after DBS for TRD is 2.5% but may not represent a significant deviation from the natural history of TRD. Finally, risks of worsening depression, anxiety, and the incidence of mania should be acknowledged when considering DBS for TRD.


Assuntos
Estimulação Encefálica Profunda , Transtorno Depressivo Resistente a Tratamento , Estimulação Encefálica Profunda/efeitos adversos , Estimulação Encefálica Profunda/métodos , Humanos , Transtorno Depressivo Resistente a Tratamento/terapia
20.
NPJ Parkinsons Dis ; 10(1): 73, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553493

RESUMO

Pain control after deep brain stimulation (DBS) in Parkinson's disease (PD) remains unclear. Following six months, subthalamic (STN)-DBS reduced sensory complaints related to parkinsonism and bodily discomfort, increasing central beta-endorphin level. Pallidal GPi-DBS decreased bodily discomfort and beta-endorphin levels. Unexplained pain by other conditions and bodily discomfort were negatively correlated with beta-endorphin levels. Thus, DBS regulates central opioids, and prioritizing STN is important for PD patients with significant sensory complications.

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