RESUMO
The increasing numbers of infections caused by multidrug-resistant (MDR) pathogens highlight the urgent need for new alternatives to conventional antibiotics. Antimicrobial peptides have the potential to be promising alternatives to antibiotics because of their effective bactericidal activity and highly selective toxicity. The present study was conducted to investigate the antibacterial, antibiofilm, and anti-adhesion activities of different CTP peptides (CTP: the original hybrid peptide cathelicidin 2 (1-13)-thymopentin (TP5); CTP-NH2: C-terminal amidated derivative of cathelicidin 2 (1-13)-TP5; CTPQ: glutamine added at the C-terminus of cathelicidin 2 (1-13)-TP5) by determining the minimal inhibitory concentrations (MICs), minimal bactericidal concentrations (MBCs), propidium iodide uptake, and analysis by scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy). The results showed that CTPs had broad-spectrum antibacterial activity against different gram-positive and gram-negative bacteria, with MICs against the tested strains varying from 2 to 64 µg/mL. CTPs at the MBC (2 × MIC 64 µg/mL) showed strong bactericidal effects on a standard methicillin-resistant Staphylococcus aureus strain ATCC 43300 after co-incubation for 6 h through disruption of the bacterial membrane. In addition, CTPs at 2 × MIC also displayed effective inhibition activity of several S. aureus strains with a 40-90% decrease in biofilm formation by killing the bacteria embedded in the biofilms. CTPs had low cytotoxicity on the intestinal porcine epithelial cell line (IPEC-J2) and could significantly decrease the rate of adhesion of S. aureus ATCC 43300 on IPEC-J2 cells. The current study proved that CTPs have effective antibacterial, antibiofilm, and anti-adhesion activities. Overall, this study contributes to our understanding of the possible antibacterial and antibiofilm mechanisms of CTPs, which might be an effective anti-MDR drug candidate.
Assuntos
Catelicidinas , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Timopentina , Biofilmes/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Testes de Sensibilidade MicrobianaRESUMO
AIM: To explore the effect of pathogenesis-based individualised thrombectomy on the clinical results and prognoses of acute intracranial large-artery occlusion. MATERIAL AND METHODS: A total of 151 patients were included in this prospective study and divided into the control group (stent thrombectomy, 53 cases), a direct aspiration first pass technique (ADAPT) group (52 cases) and the stent group (stent thrombectomy or a combination of stent thrombectomy and ADAPT, 46 cases) based on whether stent or ADAPT was used. We compared and analysed the patients? general information, the National Institutes of Health Stroke Scale (NHISS) score at admission, the time between the end of arteriography and revascularisation, the number of thrombectomies, the modified Rankin scale (mRS) score at three months and complications in the three groups. RESULTS: Compared with the control group, the time between the end of arteriography and revascularisation in the ADAPT group was significantly reduced (p < 0.05), and the patency rate after one thrombectomy significantly increased (p < 0.05). The positive prognosis rate was significantly increased in the stent and ADAPT groups compared with the control group (p < 0.05). CONCLUSION: The application of the ADAPT technique in patients with embolism-induced cerebral infarction can reduce the time of revascularisation. The use of stents in patients with atherosclerosis-induced cerebral infarction can increase the patency rate after one thrombectomy.
Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Isquemia Encefálica/complicações , Estudos Prospectivos , Estudos Retrospectivos , Trombectomia/efeitos adversos , Resultado do Tratamento , Infarto Cerebral/complicações , Artérias , Stents/efeitos adversosRESUMO
Although water soluble thiol-capped quantum dots (QDs) have been widely used as photoluminescence (PL) probes in various applications, the negative charges on thiol terminals limit the cell uptake hindering their applications in cell imaging. The commercial liposome complex (Sofast®) was used to encapsulate these QDs forming the liposome vesicles with the loading efficiency as high as about 95%. The cell uptakes of unencapsulated QDs and QD loaded liposome vesicles were comparatively studied by a laser scanning confocal microscope. We found that QD loaded liposome vesicles can effectively enhance the intracellular delivery of QDs in three cell lines (human osteosarcoma cell line (U2OS); human cervical carcinoma cell line (Hela); human embryonic kidney cell line (293 T)). The photobleaching of encapsulated QDs in cells was also reduced comparing with that of unencapsulated QDs, measured by the PL decay of cellular QDs with a continuous laser irradiation in the microscope. The flow cytometric measurements further showed that the enhancing ratios of encapsulated QDs on cell uptake are about 4-8 times in 293 T and Hela cells. These results suggest that the cationic liposome encapsulation is an effective modality to enhance the intracellular delivery of thiol-capped QDs.
Assuntos
Compostos de Cádmio/farmacocinética , Corantes Fluorescentes/farmacocinética , Lipossomos/química , Pontos Quânticos , Compostos de Sulfidrila/química , Telúrio/farmacocinética , Compostos de Cádmio/química , Células Cultivadas , Corantes Fluorescentes/química , Células HeLa , Humanos , Telúrio/química , Distribuição TecidualRESUMO
Hepatic ischemia-reperfusion (IR) injury is a common clinical issue lacking effective therapy and validated pharmacological targets. Here, using integrative 'omics' analysis, we identified an arachidonate 12-lipoxygenase (ALOX12)-12-hydroxyeicosatetraenoic acid (12-HETE)-G-protein-coupled receptor 31 (GPR31) signaling axis as a key determinant of the hepatic IR process. We found that ALOX12 was markedly upregulated in hepatocytes during ischemia to promote 12-HETE accumulation and that 12-HETE then directly binds to GPR31, triggering an inflammatory response that exacerbates liver damage. Notably, blocking 12-HETE production inhibits IR-induced liver dysfunction, inflammation and cell death in mice and pigs. Furthermore, we established a nonhuman primate hepatic IR model that closely recapitulates clinical liver dysfunction following liver resection. Most strikingly, blocking 12-HETE accumulation effectively attenuated all pathologies of hepatic IR in this model. Collectively, this study has revealed previously uncharacterized metabolic reprogramming involving an ALOX12-12-HETE-GPR31 axis that functionally determines hepatic IR procession. We have also provided proof of concept that blocking 12-HETE production is a promising strategy for preventing and treating IR-induced liver damage.
Assuntos
Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/metabolismo , Araquidonato 12-Lipoxigenase/metabolismo , Fígado/irrigação sanguínea , Receptores Acoplados a Proteínas G/metabolismo , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/antagonistas & inibidores , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/biossíntese , Animais , Modelos Animais de Doenças , Progressão da Doença , Humanos , Metabolismo dos Lipídeos , Camundongos , Traumatismo por Reperfusão/parasitologia , SuínosRESUMO
OBJECTIVE: To establish a routine procedure for the detection of p53 mutations in hepatocellular carcinoma (HCC) surgical resections using the FASAY (functional analysis of separated alleles of p53 on yeast) procedure. METHODS: p53 status was analyzed by FASAY and cDNA sequencing in 50 cases of HCC. After the extraction of RNA from the frozen tumor and corresponding normal tissues, reverse transcription RT-PCR was carried out using these samples. The assay can detect mutations of p53 mRNA between codons 67 and 347 by the DNA-binding activity of the protein and reveal them as red colonies. RESULTS: Of the 50 specimens, 29 (58%) were positive (mutant) by FASAY. Sequencing analysis confirmed that all 29 FASAY positive tumors harbored mutations, and that no mutations were detectable in any FASAY negative tumors. In 29 p53 mutations, 22 mutations were point missense mutation, 5 were deletions and 2 were splicing mutations. A novel splice mutation on splice donor of intron 6 was reported, which could produce two different mRNAs, respectively using the nearest upstream and downstream recessive splice donor sites. CONCLUSION: FASAY is a sensitive method for detecting the various types of p53 mutations in HCC, suggesting that the yeast functional assay for the detection of p53 mutations may be essential for elucidating their clinical significance.
Assuntos
Processamento Alternativo/genética , Carcinoma Hepatocelular/genética , Análise Mutacional de DNA/métodos , Neoplasias Hepáticas/genética , Proteína Supressora de Tumor p53/genética , Frequência do Gene , Testes Genéticos , Humanos , Mutação , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUNDS: Deficiency or excess of trace elements can induce body metabolic disorders and cellular growth disturbance, even mutation and cancerization. Since there are few studies of the effect of trace elements in bladder carcinoma in China, the aim of this study was thus to assess variation using a case control approach. METHODS: To determine this, 81 patients with bladder carcinoma chosen as a study group and 130 healthy persons chosen as a control group were all assayed for urinary and serum trace elements (calcium [Ca], zinc [Zn], copper [Cu], selenium [Se]) using an atomic absorption spectrophotometer, and the results were analyzed by independent sample t tests. The correlative factors on questionnaires answered by all persons were analyzed by logistic regression. RESULTS: The results showed urinary Ca, Zn and serum Cu levels of the study group to be significantly higher (P<0.05) than those of he control group. Serum Ca and Se levels of study group were significantly lower (P<0.05) than those of control group. CONCLUSION: There were higher urinary Zn and serum Cu concentrations in bladder carcinoma cases. Bladder carcinoma may be associated with Ca metabolic disorder, leading to higher urinary Ca and lower serum Ca. Low serum Se and smoking appear to be other risk factors for bladder carcinoma in China.