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1.
Artigo em Inglês | MEDLINE | ID: mdl-38831199

RESUMO

Breast cancer (BC) prevails as a major burden on global healthcare, being the most prevalent form of cancer among women. BC is a complex and heterogeneous disease, and current therapies, such as chemotherapy and radiotherapy, frequently fall short in providing effective solutions. These treatments fail to mitigate the risk of cancer recurrence and cause severe side effects that, in turn, compromise therapeutic responses in patients. Over the last decade, several strategies have been proposed to overcome these limitations. Among them, RNA-based technologies have demonstrated their potential across various clinical applications, notably in cancer therapy. However, RNA therapies are still limited by a series of critical issues like off-target effect and poor stability in circulation. Thus, novel approaches have been investigated to improve the targeting and bioavailability of RNA-based formulations to achieve an appropriate therapeutic outcome. Lipid nanoparticles (LNPs) have been largely proven to be an advantageous carrier for nucleic acids and RNA. This perspective explores the most recent advances on RNA-based technology with an emphasis on LNPs' utilization as effective nanocarriers in BC therapy and most recent progresses in their clinical applications.

2.
ACS Omega ; 9(22): 23971-23983, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38854519

RESUMO

Accurately determining the adsorption capacity of Longmaxi shale in complex structural areas is crucial for evaluating the shale gas resources in northeastern Chongqing. However, studies on the pore characteristics and methane adsorption capacity of these Longmaxi shales are currently limited. In this paper, we collected core samples from the YDB-1 well in northeastern Chongqing and determined the pore structure and adsorption capacity of the Longmaxi shale using low-pressure gas adsorption and high-temperature, high-pressure methane adsorption experiments, respectively. The results indicate that the adsorption capacity of shale in complex structural areas is significantly positively correlated with the organic matter (OM) content, weakly positively correlated with the quartz content, and weakly negatively correlated with clay minerals. Meanwhile, gas-in-place content is simultaneously controlled by the pressure and temperature of the reservoir, and with increasing depth, the adsorbed gas rapidly increases to a maximum value (at 0.8 km) and then slowly decreases, whereas the free gas continuously increases. Compared with the shale in the stable structural areas, the Longmaxi shale in complex structural areas usually develops OM-hosted pores and intergranular pores of OM and minerals and contains more micropores due to tectonic compression, resulting in a relatively larger specific surface area and adsorption capacity. This is the reason shale in complex structural areas has high development potential. The final result can provide an important basis for the evaluation of the gas content and the optimization of dessert areas in the Lower Paleozoic shale gas in southern China.

3.
J Med Chem ; 64(15): 11247-11266, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34180670

RESUMO

The emergence of multidrug-resistant bacteria has major issues for treating bacterial pneumonia. Currently, anoplin (GLLKRIKTLL-NH2) is a natural antimicrobial candidate derived from wasp venom. In this study, a series of new antimicrobial peptide (AMP) anoplin analogues were designed and synthesized. The relationship between their biological activities and their positive charge, hydrophobicity, amphipathicity, and secondary structure are described. The characteristic shared by these peptides is that positively charged amino acids and hydrophobic amino acids are severally arranged on the hydrophilic and hydrophobic surface of the α-helix to form a completely amphiphilic structure. To achieve ideal AMPs, below the range of the threshold of the cytotoxicity and hemolytic activity, their charges and hydrophobicity were increased as much. Among the new analogues, A-21 (KWWKKWKKWW-NH2) exhibited the greatest antimicrobial activity (geometric mean of minimum inhibitory concentrations = 4.76 µM) against all the tested bacterial strains, high bacterial cell selectivity in vitro, high effectiveness against bacterial pneumonia in mice infected with Klebsiella pneumoniae, and low toxicity in mice (LD50 = 82.01 mg/kg). A-21 exhibited a potent bacterial membrane-damaging mechanism and lipopolysaccharide-binding ability. These data provide evidence that A-21 is a promising antimicrobial candidate for the treatment of bacterial pneumonia.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Antineoplásicos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Pneumonia Bacteriana/tratamento farmacológico , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Venenos de Vespas/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Estrutura Molecular , Proteínas Citotóxicas Formadoras de Poros/síntese química , Proteínas Citotóxicas Formadoras de Poros/química , Relação Estrutura-Atividade
5.
Medicine (Baltimore) ; 99(15): e19508, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32282701

RESUMO

INTRODUCTION: Gastrointestinal perforation due to foreign body intake is rare and often secondary to unintentional intake; hence, a misdiagnosis is likely. Herein, we report a case of perforation of the ileum due to fish bone. CASE PRESENTATION: A 57-year-old woman presented with right lower abdominal pain. She did not provide any information about having a history of swallowing foreign bodies. Surgery for uterine fibroids and subtotal gastrectomy was performed 6 years ago. DIAGNOSIS: Laboratory tests and imaging examination showed normal results. During laparotomy, a fish bone was found at the end of the ileum. Two senior radiologists re-evaluated the computed tomography scan, and confirmed the presence of the suspected foreign body. INTERVENTIONS: Partial intestinal resection and manual ileum end anastomosis were performed. OUTCOMES: The patient recovered well after surgery and recalled that she had eaten fish the night before experiencing abdominal pain. CONCLUSION: An accurate diagnosis of complications due to fish bone intake, often secondary to the unintentional intake, is quite challenging. Detailed history-taking about the patient's diet and eating habits is therefore important. Clinical manifestations are mainly determined by the location of perforation, which typically occurs at the junction of the ileum and rectal sigmoid colon. Imaging examination and surgery are often used for definite diagnosis.


Assuntos
Perfuração Intestinal/etiologia , Alimentos Marinhos/efeitos adversos , Osso e Ossos , Feminino , Humanos , Perfuração Intestinal/cirurgia , Pessoa de Meia-Idade
7.
Eur J Pharm Sci ; 141: 105123, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676352

RESUMO

With the alarming burden of antibiotic resistance, antimicrobial peptides (AMPs) seem to be novel antimicrobial alternatives for infection treatment due to their rapid broad-spectrum antimicrobial activity and low tendency for bacterial resistance. To obtain promising AMPs, a series of new peptides were designed and synthesized by conjugating various lengths of fatty acid chains onto the side chain of the position 4 or 7 D-amino acid of Ano-D4,7 (analogue of anoplin with D-amino acid substitutions at positions 4 and 7). The new peptides exhibited excellent antimicrobial activity against a range of bacteria, especially multidrug-resistant bacteria in contrast to conventional antibiotics. Moreover, the new peptides conjugated with fatty acid chains ranging from 8 to 12 carbons in length presented preferable antimicrobial selectivity and anti-biofilm activity. Additionally, the new peptides also exerted high stability to trypsin, serum, salts and different pH environments. Most notably, the new peptides showed a low tendency to develop bacterial resistance and they displayed optimal antimicrobial activity against the obtained resistant strains. Furthermore, the results from the outer/inner membrane permeabilization and cytoplasmic membrane depolarization assays and flow cytometry and scanning electron microscopy analyses demonstrated that the new peptides exert antimicrobial effects by typical non-receptor-mediated membrane mechanisms, as well as intracellular targets characterized by gel retardation and reactive oxygen species (ROS) generation assays. Furthermore, the new peptides presented remarkable in vivo antimicrobial potency, anti-inflammatory activity, and endotoxin neutralization. Collectively, the conjugation of fatty acids to the side chains of D-amino acids is a potential strategy for designing hopeful antimicrobial alternatives to tackle the risk of bacterial resistance.


Assuntos
Aminoácidos/administração & dosagem , Antibacterianos/administração & dosagem , Ácidos Graxos/administração & dosagem , Peptídeos/administração & dosagem , Aminoácidos/química , Animais , Antibacterianos/química , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Ácidos Graxos/química , Feminino , Células HEK293 , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Peptídeos/química
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