Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Int J Pharm ; 663: 124569, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39127172

RESUMO

Doxorubicin (Dox) is a broad-spectrum antineoplastic chemotherapeutic agent used in clinical settings, yet it exhibits significant cardiotoxicity, which in severe cases can lead to heart failure. Research indicates that oxidative stress plays a pivotal role in Dox -induced cardiomyocyte injury. Therefore, the application of antioxidants represents an effective strategy to mitigate the cardiotoxic effects of doxorubicin. In preliminary studies, we isolated an antioxidative peptide, PHWWEYRR (8P). This study utilizes a PCM cardiomyocyte-targeting peptide-modified liposome as a carrier to deliver 8P into cardiomyocytes, aiming to prevent Dox-induced cardiac injury through its antioxidative mechanism. The results demonstrated that we prepared the 8P-loaded and PCM-targeting peptide-modified liposome (P-P-8P), which exhibited good dispersibility, encapsulation efficiency, drug loading capacity, and in vitro release, along with myocardial targeting capability. In vitro experiments showed that P-P-8P could prevent oxidative stress injury in H9C2 cells, protect mitochondrial functions, and inhibit cell apoptosis through a mitochondria-dependent pathway. In vivo experiments indicated that P-P-8P could prevent abnormalities in serum biochemical indicators, cardiac dysfunction, and myocardial pathological changes in mice. In conclusion, P-P-8P effectively delivers 8P to cardiomyocytes, offering protection against the cardiotoxic effects of Dox, and holds potential as a future preventative or therapeutic agent for drug-induced cardiomyopathy.


Assuntos
Antioxidantes , Doxorrubicina , Lipossomos , Miócitos Cardíacos , Estresse Oxidativo , Doxorrubicina/administração & dosagem , Animais , Antioxidantes/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/química , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Estresse Oxidativo/efeitos dos fármacos , Masculino , Camundongos , Linhagem Celular , Apoptose/efeitos dos fármacos , Cardiotoxicidade/prevenção & controle , Cardiotoxicidade/etiologia , Ratos , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/toxicidade , Miocárdio/patologia , Miocárdio/metabolismo , Liberação Controlada de Fármacos , Sistemas de Liberação de Medicamentos , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Peptídeos/química
2.
Molecules ; 29(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38893464

RESUMO

Acrylamide polymers with a high degree of polymerization are widely used in petroleum production. It is of great significance to study the oil displacement mechanism of acrylamide polymers with a high degree of polymerization from the micro level. In recent years, the rapid development of computer molecular simulation technology has filed the gaps in macroscopic experiments and theories. This technology has been highly valued in the study of the molecular behaviour of polymer systems. In this paper, the research progress of molecular simulation applied to high-polymerization-degree acrylamide polymer is summarized. The application status of acrylamide polymer flooding, the analysis of polymer flooding mechanisms, and the research progress of molecular simulation in acrylamide linear and crosslinked polymers are expounded. Finally, the development prospect of acrylamide polymer research is given, and suggestions are put forward in terms of simulation direction and simulation tools.

3.
Pest Manag Sci ; 80(9): 4564-4574, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38742692

RESUMO

BACKGROUND: Bombyx mori nuclear polyhedrosis virus (BmNPV), as a typical baculovirus, is the primary pathogen that infects the silkworm B. mori, a lepidopteran species. Owing to the high biological safety of BmNPV in infecting insects, it is commonly utilized as a biological insecticide for pest control. Apoptosis is important in the interaction between the host and pathogenic microorganisms. MicroRNAs (miRNAs) influence immune responses and promote stability of the immune system via apoptosis. Therefore, the study of apoptosis-related miRNA in silkworms during virus infection can not only provide support for standardizing the prevention and control of diseases and insect pests, but also reduce the economic losses to sericulture caused by the misuse of biological pesticides. RESULTS: Through transcriptome sequencing, we identified a miRNA, miR-31-5p, and demonstrated that it can inhibit apoptosis in silkworm cells and promote the proliferation of BmNPV in BmE-SWU1 cells. We identified a target gene of miR-31-5p, B. mori cytochrome P450 9e2 (BmCYP9e2), and demonstrated that it can promote apoptosis in silkworm cells and inhibit the proliferation of BmNPV. Moreover, we constructed transgenic silkworm strains with miR-31-5p knockout and confirmed that they can inhibit the proliferation of BmNPV. CONCLUSION: These data indicate that miR-31-5p may exert functions of inhibiting apoptosis and promoting virus proliferation by regulating BmCYP9e2. The findings demonstrate how miRNAs influence host cell apoptosis and how they are involved in the host immune system response to viruses, providing important insights into the applications of biological insecticides for pest control. © 2024 Society of Chemical Industry.


Assuntos
Apoptose , Bombyx , Sistema Enzimático do Citocromo P-450 , Proteínas de Insetos , MicroRNAs , Nucleopoliedrovírus , Animais , Bombyx/genética , Bombyx/virologia , Bombyx/crescimento & desenvolvimento , MicroRNAs/genética , MicroRNAs/metabolismo , Nucleopoliedrovírus/fisiologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Replicação Viral/efeitos dos fármacos , Linhagem Celular
4.
J Am Chem Soc ; 146(19): 13536-13545, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38693624

RESUMO

Herein, we establish a remote hydrosulfonamidation (HSA) of alkenes using palladium catalysis, where N-fluoro-N-(fluoro-sulfonyl)-carbamate with a sulfur(VI) fluoride moiety is demonstrated as a good amidation reagent. The anti-Markovnikov HSA reaction of terminal alkenes and the remote HSA of internal alkenes are achieved to efficiently yield primary N-alkyl-N-(fluorosulfonyl)-carbamates. In addition, this protocol enables the high-value utilization of alkane by combining the dehydrogenation process. The generated N-alkyl products exhibit a unique reactivity of sulfur(VI) fluorides, which can be directly transferred to N-alkyl sulfamides or amines via the sulfur(VI) fluoride exchange reaction, thereby streamlining their synthesis. Moreover, a (pyridyl) benzazole-type ligand proved to be vital for the excellent chemo- and regioselectivities.

5.
Insects ; 15(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38667394

RESUMO

Temperature is an important factor in the growth, development, survival, and reproduction of organisms. The high-temperature resistance mechanism of insects may be significant for use in the prevention and control of insect pests. The silkworm, Bombyx mori, is an important Lepidoptera model species for studies on pest control in agriculture and forestry. We identified a gene in B. mori, the B. mori singed (Bmsn) gene, which is involved in the high-temperature resistance of silkworms. Sn proteins are highly conserved among species in many taxonomic groups. The overexpression of the Bmsn gene promoted the proliferation of silkworm cells, reduced oxidation, and reduced the accumulation of reactive oxygen species under stress. Interfering with the Bmsn gene had the opposite result. We constructed a transgenic B. mori strain that overexpressed the Bmsn gene. The physiological traits of the transgenic strain were significantly improved, and it had stronger high-temperature resistance. The Bmsn gene is involved in the process by which fat bodies respond to high-temperature stress. These findings provide insights into the mechanism of high-temperature resistance of insects and offer a new perspective on agricultural and forestry pest control.

6.
Int J Biol Macromol ; 268(Pt 2): 131819, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38688334

RESUMO

The Notch signaling pathway is important in cell cycle regulation and cell proliferation. The transcriptional repressor Suppressor of Hairless [Su(H)] is a molecular switch for downstream target genes of the Notch signaling pathway but the regulatory mechanism of the Su(H) gene in the cell cycle is unclear. We determined the function of the Notch signaling pathway and Bombyx mori Su(H) [BmSu(H)] in the regulation of the silkworm cell cycle. Inhibition of Notch signaling promoted the replication of DNA in silkworm gland cells and expression of the BmSu(H) gene was significantly reduced. Overexpression of the BmSu(H) gene inhibited DNA replication and cell proliferation of silkworm cells, whereas knockout of the BmSu(H) gene promoted DNA replication and cell proliferation. Knockout of the BmSu(H) in silkworms improved the efficiency of silk gland cell endoreplication and increased important economic traits. We demonstrated that BmSu(H) protein can directly bind to the promoters of BmCyclinA, BmCyclinE and BmCDK1 genes, inhibiting or promoting their transcription at the cell and individual level. This study identified molecular targets for genetic improvement of the silkworm and also provided insights into the regulatory mechanism of the cell cycle.


Assuntos
Bombyx , Ciclo Celular , Proteínas de Insetos , Animais , Bombyx/genética , Bombyx/metabolismo , Ciclo Celular/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Receptores Notch/metabolismo , Receptores Notch/genética , Transdução de Sinais , Seda/genética , Proliferação de Células/genética , Replicação do DNA , Regiões Promotoras Genéticas/genética , Endorreduplicação , Regulação da Expressão Gênica , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
7.
Molecules ; 28(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37241984

RESUMO

Intelligent polymer gel, as a popular polymer material, has been attracting much attention for its application. An intelligent polymer gel will make corresponding changes to adapt to the environment after receiving stimuli; therefore, an intelligent polymer gel can play its role in many fields. With the research on intelligent polymer gels, there is great potential for applications in the fields of drug engineering, molecular devices, and biomedicine in particular. The strength and responsiveness of the gels can be improved under different configurations in different technologies to meet the needs in these fields. There is no discussion on the application of intelligent polymer gels in these fields; therefore, this paper reviews the research progress of intelligent polymer gel, describes the important research of some intelligent polymer gel, summarizes the research progress and current situation of intelligent polymer gel in the environment of external stimulation, and discusses the performance and future development direction of intelligent polymer gel.

8.
Front Pediatr ; 7: 138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31032240

RESUMO

Background: Survival of very-low-birth-weight infants is improving in neonatology and family-centered-care might contribute to premature infants' clinical outcomes. Aim: To evaluate a family-centered care intervention on clinical outcomes of very-low-birth-weight infants. Methods: A quasi-experimental study was conducted in a Chinese NICU between June 2016 and June 2017. The intervention included parental education of basic care knowledge and skills followed by active participation in care for at least 4 h a day. A total of 319 very-low-birth-weight infants were recruited by convenience sampling; intervention group n = 156 and control group n = 163. Primary outcome measures were weight at discharge, length-of-stay, breastfeeding, nasal feeding, total parental nutrition, re-admission, hospital expenses. Secondary outcome measures were infant complications. Results: Infants' weight at discharge was higher in the interventions group (2,654 g vs. 2,325 g, p < 0.001). Nutritional outcomes improved significantly: breastfeeding rate 139 vs. 91, p < 0.001; days of total parental nutrition 25 d vs. 32 d, p < 0.001; gastric feeding days 23 d vs. 35 d, p < 0.001. Length-of-stay and hospital expenses did not differ between both groups. Improved infants' complications were bronchopulmonary dysplasia (32 vs. 51, p = 0.031), retinopathy of prematurity (between groups no/mild and moderate/severe, p = 0.003), necrotizing enterocolitis (6 vs. 18, p = 0.019), and re-admission rate (21 vs. 38, p = 0.023). No differences were observed in intraventricular hemorrhage and nosocomial infections. Conclusion: Very-low-birth-weight premature infants might experience improved clinical health outcomes when parents are present and caring from them. Family-centered care is as a beneficial care model for premature infants and should be recognized and implemented by NICUs where parents have currently limited access.

9.
Chin Med J (Engl) ; 123(23): 3444-50, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22166529

RESUMO

BACKGROUND: Mycoplasma pneumoniae (M. pneumoniae) is a frequent cause of respiratory tract infections. However, there is deficient knowledge about the clinical manifestations of M. pneumoniae infection. We described the clinical and laboratory findings of M. pneumoniae pneumonia in hospitalized children who were all diagnosed by a ≥ fourfold increase in antibody titer. METHODS: M. pneumoniae antibodies were routinely detected in children admitted with acute respiratory infection during a one-year period. The medical history was re-collected from children whose M. pneumoniae antibody titer increased ≥ fourfold at the bedside by a single person, and their frozen paired serum samples were measured again for the M. pneumoniae antibody titer. RESULTS: Of the 635 children whose sera were detected for the M. pneumoniae antibody, paired sera were obtained from 82 and 29.3% (24/82) showed a ≥ fourfold increase in antibody titer. There were 24 cases, nine boys and 15 girls, aged from two to 14 years, whose second serum samples were taken on day 9 at the earliest after symptom onset; the shortest interval was three days. All children presented with a high fever (≥ 38.5°C) and coughing. Twenty-one had no nasal obstruction or a runny nose, and five had mild headaches which all were associated with the high fever. The disease was comparatively severe if the peak temperature was > 39.5°C. All were diagnosed as having pneumonia through chest X-rays. Four had bilateral or multilobar involvement and their peak temperatures were all ≤ 39.5°C. None of the children had difficulty in breathing and all showed no signs of wheezing. CONCLUSIONS: The second serum sample could be taken on day 9 at the earliest after symptom onset meant that paired sera could be used for the clinical diagnosis of M. pneumoniae pneumonia in children at the acute stage. M. pneumoniae is a lower respiratory tract pathogen. Extrapulmonary complications were rare and minor in our study. High peak temperature (> 39.5°C) is correlated with the severity of M. pneumoniae pneumonia in children.


Assuntos
Pneumonia por Mycoplasma/complicações , Doença Aguda , Adolescente , Anticorpos Antibacterianos/sangue , Criança , Criança Hospitalizada , Pré-Escolar , Feminino , Humanos , Masculino , Mycoplasma pneumoniae/imunologia , Pneumonia por Mycoplasma/diagnóstico , Pneumonia por Mycoplasma/tratamento farmacológico , Radiografia Torácica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA