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1.
Front Bioeng Biotechnol ; 11: 1217067, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324430

RESUMO

In severe or complex cases of peripheral nerve injuries, autologous nerve grafts are the gold standard yielding promising results, but limited availability and donor site morbidity are some of its disadvantages. Although biological or synthetic substitutes are commonly used, clinical outcomes are inconsistent. Biomimetic alternatives derived from allogenic or xenogenic sources offer an attractive off-the-shelf supply, and the key to successful peripheral nerve regeneration focuses on an effective decellularization process. In addition to chemical and enzymatic decellularization protocols, physical processes might offer identical efficiency. In this comprehensive minireview, we summarize recent advances in the physical methods for decellularized nerve xenograft, focusing on the effects of cellular debris clearance and stability of the native architecture of a xenograft. Furthermore, we compare and summarize the advantages and disadvantages, indicating the future challenges and opportunities in developing multidisciplinary processes for decellularized nerve xenograft.

2.
Medicina (Kaunas) ; 59(5)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37241124

RESUMO

The incidence of traumatic testicular dislocation is rare, and it is usually overlooked in an initial diagnosis. We present a case of bilateral dislocated testes after a traffic accident that was treated via orchidopexy one week later. No testicular complications had occurred by the time of the follow-up visit. Generally, surgery is often postponed owing to a late diagnosis or another major organ injury, and the adequate timing of surgery is still under debate. We performed a review of past cases, which showed similar testicular outcomes irrespective of surgical timing. Delayed intervention may be a feasible decision after a patient's hemodynamic status is stable for surgery. To prevent delayed diagnosis, scrotal examination should not be overlooked in any patients presenting with pelvic trauma to the emergency department.


Assuntos
Acidentes de Trânsito , Testículo , Masculino , Humanos , Testículo/cirurgia , Testículo/lesões , Diagnóstico Tardio , Serviço Hospitalar de Emergência
3.
Diagnostics (Basel) ; 13(9)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37174919

RESUMO

Enterovesical fistula (EVF) is a rare complication of Crohn's disease (CD), characterized by recurrent urinary tract infections, fecaluria, and pneumaturia. However, most diagnostic tools have low sensitivity for EVF. Management consists of conservative and surgical approaches. Conservative treatment is usually adopted first. However, the appropriate time to consider surgery remains controversial. Herein, we report on the case of a 34-year-old male who presented with diffuse abdominal pain with fullness for one day. Enteroscopy and biopsy confirmed the diagnosis of Crohn's disease. Contrast-enhanced computed tomography (CT) suggested a fistula between the ileum and urinary bladder; however, cystoscopy did not find an obvious tract. The patient initially received medical treatment, but the symptoms persisted with recurrent urinary tract infections and subsequent bilateral hydronephrosis. He then underwent successful fistulectomy, partial cystectomy, and two segmental resections of the small bowel with end-to-end primary sutures. No complications or symptomatic urinary tract infections were noted during 30 months of follow-up after surgery, suggesting no recurrence of EVF. Surgical intervention is warranted when medical treatment fails or complications occur. Clinical symptoms and laboratory data are often less informative for the diagnosis of EVF, and CT is the most helpful diagnostic modality. Our management strategy provides an option for such patients.

4.
Polymers (Basel) ; 14(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298044

RESUMO

In this study, we prepared three benzo[ghi]perylenetriimide (BPTI) conjugated molecules as electron-transporting surface-modifying layers for polymer solar cells (PSCs). These three BPTI derivatives differed in the nature of their terminal functionalities, featuring butylamine (C3NH2), propylammonium iodide (C3NH3I), and butyldimethylamine (C3DMA) units, respectively. We evaluated the optoelectronic properties of PTB7-Th: PC71BM blends modified with these interfacial layers, as well as the performance of resulting PSCs. We used UV-Vis spectroscopy, atomic force microscopy, surface energy analysis, ultraviolet photoelectron spectroscopy, and photoelectric flow measurements to examine the phenomena behind the changes in the optoelectronic behavior of these blend films. The presence of a BPTI derivative changed the energy band alignment at the ZnO-active layer interface, leading to the ZnO film behaving more efficiently as an electron-extraction electrode. Modifying the ZnO surface with the BPTI-C3NH3I derivative resulted in a best power conversion efficiency (PCE) of 10.2 ± 0.53% for the PTB7-Th:PC71BM PSC (cf. PCE of the control device of 9.1 ± 0.13%). In addition, modification of a PM6:Y6:PCBM PSC with the BPTI-C3NH3I derivative increased its PCE from 15.6 ± 0.25% to 16.5 ± 0.18%. Thus, BPTI derivatives appear to have potential as IFLs when developing high-performance PSCs, and might also be applicable in other optoelectronic devices.

5.
Molecules ; 26(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34500594

RESUMO

Lung cancer is the most commonly diagnosed malignant cancer in the world. Non-small-cell lung cancer (NSCLC) is the major category of lung cancer. Although effective therapies have been administered, for improving the NSCLC patient's survival, the incident rate is still high. Therefore, searching for a good strategy for preventing NSCLC is urgent. Traditional Chinese medicine (TCM) are brilliant materials for cancer chemoprevention, because of their high biological safety and low cost. Bavachinin, which is an active flavanone of Proralea corylifolia L., possesses anti-inflammation, anti-angiogenesis, and anti-cancer activities. The present study's aim was to evaluate the anti-cancer activity of bavachinin on NSCLC, and its regulating molecular mechanisms. The results exhibited that a dose-dependent decrease in the cell viability and colony formation capacity of three NSCLC cell lines, by bavachinin, were through G2/M cell cycle arrest induction. Meanwhile, the expression of the G2/M cell cycle regulators, such as cyclin B, p-cdc2Y15, p-cdc2T161, and p-wee1, was suppressed. With the dramatic up-regulation of the cyclin-dependent kinase inhibitor, p21Waf1/Cip1, the expression and association of p21Waf1/Cip1 with the cyclin B/cdc2 complex was observed. Silencing the p21Waf1/Cip1 expression significantly rescued bavachinin-induced G2/M cell accumulation. Furthermore, the expression of p21Waf1/Cip1 mRNA was up-regulated in bavachinin-treated NSCLC cells. In addition, MAPK and AKT signaling were activated in bavachinin-added NSCLC cells. Interestingly, bavachinin-induced p21Waf1/Cip1 expression was repressed after restraint p38 MAPK activation. The inhibition of p38 MAPK activation reversed bavachinin-induced p21Waf1/Cip1 mRNA expression and G2/M cell cycle arrest. Collectively, bavachinin-induced G2/M cell cycle arrest was through the p38 MAPK-mediated p21Waf1/Cip1-dependent signaling pathway in the NSCLC cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Flavonoides/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Células A549 , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina B1 , Inibidor de Quinase Dependente de Ciclina p21/genética , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Humanos , Neoplasias Pulmonares/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Transdução de Sinais/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética
6.
Mater Sci Eng C Mater Biol Appl ; 114: 111025, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32994007

RESUMO

Conventional chemotherapeutic drugs are nonselective and harmful toward normal tissues, causing severe side effects. Therefore, the development of chemotherapeutics that can target cancer cells and improve therapeutic efficacy is of high priority. Biomolecules isolated from nature serve as green solutions for biomedical use, solving biocompatibility and cytotoxicity issues in human bodies. Herein, we use kiwifruit-derived DNA to encapsulate doxorubicin (DOX) using crosslinkers, eventually forming DNA-DOX nanogels (NGs). Drug releasing assays, cell viability and anticancer effects were analyzed to evaluate the DNA NGs' applications. The amount of DOX released by the DOX-loaded DNA (DNA-DOX) NGs at acidic pH was higher than that of neutral pH, and high glutathione (GSH) concentration also triggered more DOX to release in cancer cells, demonstrating pH- and GSH-triggered drug release characteristics of the DNA NGs. The IC50 of DNA-DOX NGs in cancer cells was lower than that of free DOX. Moreover, DOX uptake of cancer cells and apoptotic death were enhanced by the DNA-DOX NGs compared to free DOX. The results suggest that the DNA NGs cross-linked via nitrogen bases of the nucleotides in DNA and presenting pH- and GSH-dependent drug releasing behavior can be alternative biocompatible drug delivery systems for anticancer strategies and other biomedical applications.


Assuntos
Antineoplásicos , Glutationa , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos/farmacologia , Sobrevivência Celular , Doxorrubicina/farmacologia , Portadores de Fármacos/farmacologia , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Nanogéis
7.
Biomacromolecules ; 21(9): 3836-3846, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32790281

RESUMO

Cancer metastasis is a central oncology concern that worsens patient conditions and increases mortality in a short period of time. During metastatic events, mitochondria undergo specific physiological alterations that have emerged as notable therapeutic targets to counter cancer progression. In this study, we use drug-free, cationic peptide fibrillar assemblies (PFAs) formed by poly(L-Lysine)-block-poly(L-Threonine) (Lys-b-Thr) to target mitochondria. These PFAs interact with cellular and mitochondrial membranes via electrostatic interactions, resulting in membranolysis. Charge repulsion and hydrogen-bonding interactions exerted by Lys and Thr segments dictate the packing of the peptides and enable the PFAs to display enhanced membranolytic activity toward cancer cells. Cytochrome c (cyt c), endonuclease G, and apoptosis-inducing factor were released from mitochondria after treatment of lung cancer cells, subsequently inducing caspase-dependent and caspase-independent apoptotic pathways. A metastatic xenograft mouse model was used to show how the PFAs significantly suppressed lung metastasis and inhibited tumor growth, while avoiding significant body weight loss and mortality. Antimetastatic activities of PFAs are also demonstrated by in vitro inhibition of lung cancer cell migration and clonogenesis. Our results imply that the cationic PFAs achieved the intended and targeted mitochondrial damage, providing an efficient antimetastatic therapy.


Assuntos
Neoplasias Pulmonares , Animais , Apoptose , Caspases , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Mitocôndrias
8.
PLoS One ; 9(1): e86718, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24489775

RESUMO

Adaptation of enzymes in a metabolic pathway can occur not only through changes in amino acid sequences but also through variations in transcriptional activation, mRNA splicing and mRNA translation. The heme biosynthesis pathway, a linear pathway comprised of eight consecutive enzymes in animals, provides researchers with ample information for multiple types of evolutionary analyses performed with respect to the position of each enzyme in the pathway. Through bioinformatics analysis, we found that the protein-coding sequences of all enzymes in this pathway are under strong purifying selection, from cnidarians to mammals. However, loose evolutionary constraints are observed for enzymes in which self-catalysis occurs. Through comparative genomics, we found that in animals, the first intron of the enzyme-encoding genes has been co-opted for transcriptional activation of the genes in this pathway. Organisms sense the cellular content of iron, and through iron-responsive elements in the 5' untranslated regions of mRNAs and the intron-exon boundary regions of pathway genes, translational inhibition and exon choice in enzymes may be enabled, respectively. Pathway product (heme)-mediated negative feedback control can affect the transport of pathway enzymes into the mitochondria as well as the ubiquitin-mediated stability of enzymes. Remarkably, the positions of these controls on pathway activity are not ubiquitous but are biased towards the enzymes in the upstream portion of the pathway. We revealed that multiple-level controls on the activity of the heme biosynthesis pathway depend on the linear depth of the enzymes in the pathway, indicating a new strategy for discovering the molecular constraints that shape the evolution of a metabolic pathway.


Assuntos
Vias Biossintéticas/genética , Evolução Molecular , Heme/biossíntese , Regiões 5' não Traduzidas/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Aminoácidos/genética , Animais , Sequência de Bases , Sequência Conservada/genética , Desoxirribonucleases/metabolismo , Éxons/genética , Genes , Íntrons/genética , Dados de Sequência Molecular , Elementos de Resposta/genética , Seleção Genética , Alinhamento de Sequência
9.
J Pharm Biomed Anal ; 38(3): 551-5, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15925259

RESUMO

A sensitive high-performance liquid chromatography method with electrochemical detection was developed for the purpose of determining the concentration of the new anti-tumor agent 1-[4-(furo[2,3-b]-quinolin-4-ylamino)phenyl]ethanone (FQPE) in rats. The plasma samples were spiked with the internal standard diclofenac and extracted using dichloromethane. A C(18) 250 mm x 4mm column was used for the separation of analyte with a mobile phase consisting of 50% acetonitrile and 50% pH 3.0 of sodium 1-pentansulfonate solution at a flow rate of 1.0 mL/min. FQPE was detected by electrochemical detector at 1.0 V and 20 nA. Intra-day and inter-day precision and accuracy were acceptable down to the limit of quantization of 1 ng/mL. The lower limit of detection (LOD) was 0.5 ng/mL. The pharmacokinetic parameters of FQPE in rats after intravenous administration of 2.1 and 4.2 mg/kg were determined. The apparent volume of distribution, half-life of elimination, and clearance showed no significant difference between the two dosages. The area under the plasma concentration time curve increased proportionally with dose. The half-life of FQPE was prolonged about 2.4-fold, compared with amsacrine.


Assuntos
Antineoplásicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Eletroquímica/métodos , Quinolinas/sangue , Amsacrina/sangue , Amsacrina/química , Amsacrina/farmacocinética , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Área Sob a Curva , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Meia-Vida , Estrutura Molecular , Quinolinas/química , Quinolinas/farmacocinética , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Tecnologia Farmacêutica/métodos
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