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[This corrects the article DOI: 10.3389/fneur.2020.584446.].
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The ability of isolated surface layer proteins (SLPs) to reassemble on suitable surfaces enables the application of SLPs in various fields of nanotechnology. In this work, SLPs from Lactobacillus buchneri BNCC 187,964 and L. kefir BNCC 190,565 were extracted and verified as glycosylated proteins. They were applied to coat on the surface of cationic liposomes. The absorption of the two SLPs on liposomes induced the zeta potential reduction and particle size increase. The two kinds of SLP-coated liposomes demonstrated better thermal, light and pH stability than the control liposomes. And the L. kefir SLP showed better protective effects than the L. buchneri SLP. Moreover, both of the SLPs could endow liposomes with the function of binding ferritin as observed by transmission electron microscope. Fourier transform infrared spectroscopy illustrated that the interaction between the two SLPs and liposomes was similar. The recrystallization of the two SLPs on the liposomes might drive the lipid into a higher order state and hydrogen bonds were formed between the two SLPs and the liposomes. All the findings demonstrated that L. kefir SLP and L. buchneri SLP had great potential to be explored as effective coating agents to improve the stability and function of cationic liposomes.Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.Yes, all have been checked.
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Lactobacillus , Lipossomos , Cátions , Glicoproteínas de MembranaRESUMO
Surface layer proteins (SLPs) are crystalline arrays in the outermost layer of cell envelope in many archaea and bacteria. SLPs subunits have the ability to reassemble on the surface of lipid layers. In this work, the SLP from Lactobacillus acidophilus ATCC 4356 was extracted and reassembled on the surface of positively charged liposomes composed of dipalmitoyl phosphatidylcholine, cholesterol and octadecylamine. Zeta potentials and particle size were determined to describe the adsorption process of SLP on liposomes. The liposomes completely coated with SLP were observed by transmission electron microscope. To investigate the stabilizing effects of SLP on liposomes, carboxyfluorescein (CF) was encapsulated and its leakage was determined as an evaluation index. The results showed that the L. acidophilus ATCC 4356 SLP significantly (P < 0.05) increased the stability of the liposomes in the course of thermal challenge. Furthermore, SLP was able to reduce the aggregation of liposomes in serum. Storage stability of liposomes was performed at 25 °C, 4 °C and -20 °C for 90 days. And the SLP-coated liposomes released less CF than the control liposomes during storage at the three evaluated temperatures. Our findings extended the application field of Lactobacillus SLPs and introduced a novel nanocarrier system with good chemical stability.
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Proteínas de Bactérias/química , Lactobacillus acidophilus , Lipídeos/química , Tensoativos/química , 1,2-Dipalmitoilfosfatidilcolina/química , Aminas/química , Proteínas de Bactérias/isolamento & purificação , Colesterol/química , Lactobacillus acidophilus/metabolismo , Lipossomos , Nanopartículas , Propriedades de Superfície , Tensoativos/isolamento & purificação , Temperatura , Fatores de TempoRESUMO
Escherichia coli and Salmonella are common pathogenic bacteria in human intestine, which can infect epithelial cells and cause diseases. Adhesion to intestinal tissue is the first step of pathogen infection. This work was to investigate the protective function of surface layer protein (SLP) from Lactobacillus casei fb05 against the harmful effects of E. coli and Salmonella on intestinal tissue (collagen and HT-29 cells). The SLP of L. casei fb05 was identified by transmission electron microscopy and SDS-PAGE. The purified SLP could reduce the adhesion of E. coli and Salmonella to collagen and HT-29 cells as observed by light microscope. The flow cytometry results showed that the L. casei fb05 SLP decreased the two pathogens-induced apoptosis of HT-29 cells by about 45%-49%. In addition, the activation of caspase-9 and caspase-3 caused by the two pathogens was significantly declined by the interference of the L. casei fb05 SLP. All the findings demonstrated that the L. casei fb05 SLP could decrease the deleterious effects of E. coli and Salmonella on intestinal tract in two ways: reducing pathogen adhesion and inhibiting pathogen-induced apoptosis. The potential of L. casei fb05 SLP in the treatment of intestinal diseases might be explored in this work.
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Escherichia coli/patogenicidade , Intestinos/microbiologia , Lacticaseibacillus casei/metabolismo , Glicoproteínas de Membrana/metabolismo , Salmonella typhimurium/patogenicidade , Apoptose , Aderência Bacteriana , Caspase 3/metabolismo , Caspase 9/metabolismo , Colágeno/metabolismo , Células HT29 , Humanos , Fatores de ProteçãoRESUMO
BACKGROUND: Benign convulsions with mild gastroenteritis (BCWG) is a common condition in children in Asia and is generally not associated with pH or electrolyte imbalances. When BCWG is diagnosed, a lumbar puncture is usually recommended to rule out potential intracranial infections. This study examined the clinical characteristics of BCWG and evaluated the necessity of lumbar puncture. METHODS: Medical records of children admitted to the First Hospital of Jilin University with BCWG between January 2018 and May 2019 were reviewed and analyzed. Children were stratified by rotavirus positivity or lumbar puncture status. Clinical characteristics and long-term outcomes were compared between groups. RESULTS: A total of 51 children were included in the analyses (55.1% rotavirus [HRV] positive). The average age of convulsion onset was 21.12 ± 7.44 months, the male-to-female ratio was 1.8:1, and convulsions occurred primarily between October 2018 and April 2019. The main clinical presentations of BCWG were convulsions, vomiting, diarrhea, and fever. Convulsions occurred predominantly two days after diagnosis of gastroenteritis, were mainly generalized tonic-clonic with 88.2% of children having ≤ 3 convulsions per episode, and had a mean duration of 2.0 minutes (interquartile range [IQR]: 1.0, 3.0). Children with BCWG had mild metabolic acidosis (HCO3- 17.82 ± 3.63 mmol/L) with an elevated anion gap (AG; 20.98 ± 3.00 mmol/L), mild hyponatremia (134.56 ± 2.85 mmol/L), and slightly increased levels of creatine kinase myocardial band (CKMB). HRV + children had more severe acidosis and higher CKMB levels. Cerebrospinal fluid (CSF) samples collected via lumbar puncture were normal. No developmental abnormalities were noted as assessed by the Social Life Ability Scale. CONCLUSIONS: BCWG is a situation-related seizure, with clinical presentations of tonic-clonic or focal convulsions and mild gastroenteritis (vomiting, diarrhea). Mild metabolic acidosis and hyponatremia may exist. The prognosis of the disease is favorable; lumbar puncture and long-term antiepileptics are unnecessary and should not be recommended.
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Gastroenterite , Infecções por Rotavirus , Ásia , Criança , Pré-Escolar , Feminino , Gastroenterite/complicações , Gastroenterite/diagnóstico , Gastroenterite/terapia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Convulsões/diagnóstico , Convulsões/etiologiaRESUMO
Objective: To explore the effectiveness and safety of mycophenolate mofetil (MMF) as a second-line medication in the treatment of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis, the most common and severe autoimmune encephalitis. Methods: The clinical data of six children with anti-NMDAR encephalitis admitted to the First Hospital of Jilin University were retrospectively analyzed, and the effectiveness and safety of MMF were evaluated. Results: Six children with anti-NMDAR encephalitis were treated with MMF in the 2nd or 3rd treatment disease event (3 cases vs. 3 cases). MMF initiation was mean 19.2 months (range 6-39 months) after disease onset at a mean dose of 25.6 mg/kg (range 19.6-28.4 mg/kg) for 14 months (range 6-26 months). Only two patients had transient mild diarrhea within 2 weeks of MMF application. During follow-up, one patient relapsed whilst on MMF, one patient discontinued MMF, and 4 cases were still on MMF. Conclusion: The use of MMF in anti-NMDAR encephalitis may be effective and safe. MMF can be used as one of the relapse prevention options in patients who already have relapsed or possibly even after the first event. Delayed use may be the main reason for MMF failure.
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Colorectal cancer (CRC) is the third most common cancer and the fourth leading cause of cancer death around the world. The current treatments of CRC exhibited high occurrence rate of side effects. Docetaxel (DTX), an important drug widely used in cancer chemotherapy, showed serious toxicity in CRC. Reducing toxicity of DTX could be a feasible and promising way to achieve the new indication of DTX for CRC. In this study, a series of MMP-7 activated octapeptide-DTX/4FDT prodrugs (6a-10a and 6b-10b) were designed and synthesized based on the features of MMP-7 which is highly expressed in CRC and could specially recognize octapeptides with specific sequences. Among them, 9a and 9b, both possessing an octapeptide Gly-Pro-Gln-Gly-Ile-Ala-Met-Gln moiety, were the most potent prodrugs. Compounds 9a and 9b were also tested their release rate in HCT116 cell culture fluids and tumor homogenate along with in vivo anti-CRC activity and systemic toxicity. Since 9a showed better anti-CRC activity and lower systemic toxicity than 9b in CRC tumor bearing mice, it was further evaluated for its acute toxicity, pharmacokinetics and tissue distribution in comparison with its parent drug DTX. These results revealed that 9a possessed good systemic stability, rapid release rate in CRC and reduced systemic toxicity, while retaining similar anti-CRC activity to its parent drug DTX. Thus, 9a, an MMP-7 polypeptide prodrug of DTX, has been identified as a promising candidate for the treatment of CRC.
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Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Docetaxel/farmacologia , Metaloproteinase 7 da Matriz/metabolismo , Oligopeptídeos/farmacologia , Pró-Fármacos/farmacologia , Animais , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Docetaxel/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Oligopeptídeos/química , Pró-Fármacos/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
Rogressive deconstruction of filament actin (F-actin) in hippocampal neurons in the epileptic brain have been associated with epileptogenesis. Previous clinical studies suggest that glucocorticoids treatment plays beneficial roles in refractory epilepsy. Glucocorticoids treatment affects dendritic spine morphology by regulating local glucocorticoid receptors and F-actin cytoskeleton dynamics. However, how glucocorticoids regulate epileptogenesis by controlling F-actin cytoskeleton is not clear yet. Here we study the function of glucocorticoids in epileptogenesis by examining F-actin abundance, hippocampal neuron number, and synaptic markers in pilocarpine-induced epileptic mice in the presence or absence of dexamethasone (DEX) treatment. We found that spontaneous seizure duration was significantly reduced; F-actin damage in hippocampal subfields was remarkably attenuated; loss of pyramidal cells was dramatically decreased; more intact synaptic structures indicated by pre- and postsynaptic markers were preserved in multiple hippocampal regions after DEX treatment. However, the number of ZNT3 positive particles in the molecular layer in the hippocampus of pilocarpine epileptic mice was not altered after DEX treatment. Although not sufficient to cease epileptogenesis, our results suggest that dexamethasone treatment ameliorates the damage of epileptic brain by stabilizing F-actin cytoskeleton in the pilocarpine epileptic mice.
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Citoesqueleto de Actina/metabolismo , Anti-Inflamatórios/uso terapêutico , Dexametasona/uso terapêutico , Epilepsia/metabolismo , Hipocampo/metabolismo , Pilocarpina/toxicidade , Citoesqueleto de Actina/química , Animais , Anti-Inflamatórios/farmacologia , Dexametasona/farmacologia , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Hipocampo/química , Hipocampo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICRAssuntos
DNA Polimerase Dirigida por DNA/genética , Esclerose Cerebral Difusa de Schilder/genética , Mutação , DNA Polimerase gama , Esclerose Cerebral Difusa de Schilder/diagnóstico , Esclerose Cerebral Difusa de Schilder/tratamento farmacológico , Esclerose Cerebral Difusa de Schilder/etiologia , Heterozigoto , Humanos , Lactente , MasculinoRESUMO
N-De-tert-butoxycarbonyl-N-[2-(1,1,1-trifluoro-2-methyl)propyloxycarbonyl]-2-debenzoyl-2-(m-fluorobenzoyl)-docetaxel (4FDT), a novel fluorinated docetaxel analog, was evaluated for its anti-hepatoma effect and possible druggability. In molecular docking studies, 4FDT coincided with paclitaxel in a part of the nucleus. In in vitro studies, 4FDT demonstrated higher anti-hepatoma activity approximately 1.5 times greater than that of docetaxel. More interestingly, 4FDT had been determined to have better anticancer effects, even 90 times greater in patient-derived xenografts (PDX) liver cancer cell lines than sorafenib. In the in vivo studies, 4FDT could effectively reduce the growth rate of liver cancer H22 and HepG2 cells. Furthermore, in a preliminary study on the ex vivo distribution of 4FDT, 4FDT-IR783 was primarily concentrated in the liver 1h after injection, and most of it was metabolized from the liver in 24h. Finally, the acute toxicity test revealed fewer side effects for 4FDT (approximately 16% than docetaxel). The water solubility, which was 11 times greater than that of docetaxel, confirmed the good druggability of 4FDT. All of these results demonstrated 4FDT's great potential to be a candidate drug for liver cancer treatment.
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Carcinoma Hepatocelular/tratamento farmacológico , Simulação por Computador , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Experimentais/tratamento farmacológico , Taxoides/química , Taxoides/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Domínio Catalítico , Linhagem Celular Tumoral , Docetaxel , Relação Dose-Resposta a Droga , Modelos Biológicos , Modelos Moleculares , Estrutura Molecular , Conformação Proteica , Relação Estrutura-Atividade , Taxoides/toxicidadeRESUMO
By-product 9a exhibited potent cytotoxicity against both SK-OV-3 and A549 cell lines. The structure of 9a was characterized using 1D and 2D NMR experiments and confirmed by synthesis to afford a diastereomeric mixture (16a) that was identical to 9a, as well as a pair of diastereomers (R)-16b and (S)-16c. The preliminary SAR study demonstrated that analogs with an (R)-configuration were slightly more potent than analogs with an (S)-configuration. In addition, α,α-gem-dimethyl analogs 16 g-i were the most potent analogs in this series, exhibiting similar potency to docetaxel and greater potency than Taxol against the SK-OV-3 cell line. For the A549 cell line, analogs 16 g-i were more potent (>65-fold) than both docetaxel and Taxol.
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Antineoplásicos/síntese química , Desenho de Fármacos , Taxoides/química , Antineoplásicos/química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Docetaxel , Humanos , Paclitaxel/química , Paclitaxel/toxicidade , Estereoisomerismo , Relação Estrutura-Atividade , Taxoides/síntese química , Taxoides/toxicidadeRESUMO
Nine new 3'-N-phenylsulfonyl docetaxel analogs were synthesized in good yields from the key intermediate N-phenylsulfonyl oxazolidine via a six-step route. These analogs were tested for anti-hepatitis B virus (HBV) activity in vitro. Compounds 3e, 3g and 3j showed more potent inhibitory activity against HBeAg secretion than the positive control lamivudine. Further extensive SAR and mechanistic studies will be reported in due course.
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Antivirais/síntese química , Vírus da Hepatite B/efeitos dos fármacos , Sulfonas/síntese química , Taxoides/síntese química , Antivirais/farmacologia , Docetaxel , Avaliação Pré-Clínica de Medicamentos , Células Hep G2 , Humanos , Paclitaxel/farmacologia , Relação Estrutura-Atividade , Sulfonas/farmacologia , Taxoides/farmacologiaRESUMO
In the title compound, C20H19NO4, the absolute configuration (3R,4S) for the two chiral centres of the mol-ecule has been determined.
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OBJECTIVE: To investigate the clinical efficacy and safety of oxcarbazepine (OXC) suspension in children with focal epilepsy. METHODS: A total of 118 children aged 2-14 years, who were newly diagnosed with focal epilepsy between October 2009 and December 2011, were randomly divided into experimental group (n=60) and control group (n=58). The experimental group was treated with an orally suspension of OXC and the control group was orally administered with carbamazepine (CBZ) tablets. The two treatment regimens were compared in terms of clinical efficacy and safety. RESULTS: After 13 and 26 weeks of treatment, the experimental group had response rates of 75% and 72% respectively and seizure-free rates of 53% and 50%, and the control group had response rates of 71% and 66% and seizure-free rates of 50% and 43% respectively. There were no significant differences in the clinical efficacy between the two groups (P>0.05). After 26 weeks of treatment, the adverse event rates of the experimental and control groups were 18% and 40% respectively, with a significant difference between the two groups (P<0.05). CONCLUSIONS: OXC suspension has a comparable clinical efficacy to that of CBZ tablets in children aged 2-14 years who are newly diagnosed with focal epilepsy, but OXC suspension causes fewer adverse events and has higher safety.