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1.
Inorg Chem ; 61(3): 1512-1520, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34969248

RESUMO

Maintaining a long-term continuous and stable reactivator blood concentration to treat organophosphorus nerve agent poisoning using acetylcholinesterase (AChE) reactivator pralidoxime chloride (2-PAM) is very important yet difficult. Because the flexible framework of MIL-88B(Fe) nanoparticles (NPs) can swell in polar solvents, pralidoxime chloride (2-PAM) was loaded in MIL-88B(Fe) NPs (size: ca. 500 nm) by stirring and incubation in deionized water to obtain 2-PAM@MIL-88B(Fe), which had a maximum drug loading capacity of 12.6 wt %. The as-prepared composite was characterized by IR, powder X-ray diffraction (P-XRD), scanning electron microscopy (SEM), ζ-potential, Brunauer-Emmett-Teller (BET), and thermogravimetry/differential thermal analysis (TG/DTA). The results showed that under constant conditions, the maximum drug release rates of 2-PAM@MIL-88B(Fe) in absolute ethanol, phosphate-buffered saline (PBS) solution (pH = 7.4), and PBS solution (pH = 4) at 150 h were 51.7, 80.6, and 67.1%, respectively. This was because the composite showed different swelling behaviors in different solvents. In PBS solution with pH = 2, the 2-PAM@MIL-88B(Fe) framework collapsed after 53 h and released 100% of 2-PAM. For mice after intragastric poisoning with sarin (a neurotoxic agent), an atropine-assisted 2-PAM@MIL-88B(Fe) treatment experiment revealed that 2-PAM@MIL-88B(Fe) continuously released 2-PAM for more than 72 h so that poisoned AChE was continuously and steadily reactivated. The reactivation rate of AChE was 56.7% after 72 h. This composite is expected to provide a prolonged, stable therapeutic drug for the mid- and late-stage treatment of neurotoxic agent poisoning.


Assuntos
Estruturas Metalorgânicas/química , Agentes Neurotóxicos/farmacologia , Compostos de Pralidoxima/farmacologia , Sarina/antagonistas & inibidores , Acetilcolinesterase/análise , Acetilcolinesterase/metabolismo , Administração Oral , Animais , Atropina/administração & dosagem , Atropina/farmacologia , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos , Nanopartículas/química , Agentes Neurotóxicos/química , Compostos de Pralidoxima/administração & dosagem , Compostos de Pralidoxima/química , Sarina/administração & dosagem , Sarina/toxicidade
2.
Inorg Chem ; 59(16): 11595-11605, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799468

RESUMO

Due to the unpredictable nature of a battlefield environment, in the simultaneous degradation of sulfur mustard and nerve agents it is preferable to use just one decontaminant. Herein, the new composite HPVMo@MOF-808 (HPVMo = H5PV2Mo10O40) was deliberately synthesized via a simple impregnation method and thoroughly characterized. The results showed that the decontamination rate of the composites (30-40 mg) with optimal HPVMo loadings for HD (4 µL) and GD (4 µL) under ambient conditions was 97.2% (within 120 min) and 90.8% (within 30 min), respectively. Due to the combinational/synergistic effect of MOF-808 and encapsulated homogeneously dispersed HPVMo, the composite can very efficiently oxidize HD to nontoxic products in a single system, while retaining the inherent excellence of MOF-808 in hydrolytically degrading GD. The decontamination process was found to follow first-order reaction kinetics, and the rate constant and half-life of the composite for HD and GD were 0.0231 min-1, 30.13 min and 0.0795 min-1, 8.72 min, respectively. In addition, experimental results in guinea pigs and Kunming mice used as animal models showed that the composite provided effective skin protection against HD and GD, showing great potential for application in skin decontamination and protection.


Assuntos
Substâncias para a Guerra Química/química , Estruturas Metalorgânicas/química , Gás de Mostarda/química , Soman/química , Compostos de Tungstênio/química , Animais , Substâncias para a Guerra Química/intoxicação , Cobaias , Camundongos , Intoxicação/prevenção & controle
3.
Bioorg Chem ; 81: 681-688, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30265992

RESUMO

A new series of nonquaternary conjugates for reactivation of both nerve agents and pesticides inhibited hAChE were described in this paper. It was found that substituted salicylaldehydes conjugated to aminobenzamide through piperidine would produce efficient reactivators for sarin, VX and tabun inhibited hAChE, such as L6M1R3, L6M1R5 to L6M1R7, L4M1R3 and L4M1R5 to L4M1R7. The in vitro reactivation experiment for pesticides inhibited hAChE of these new synthesized oximes were conducted for the first time. Despite they were less efficient than obidoxime, some of them were highlighted as equal or more efficient reactivators in comparison to 2-PAM. It was found that introduction of peripheral site ligands could increase oximes' binding affinity for inhibited hAChE in most cases, which resulted in greater reactivation ability.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/toxicidade , Desenho de Fármacos , Ativadores de Enzimas/química , Ativadores de Enzimas/farmacologia , Agentes Neurotóxicos/toxicidade , Praguicidas/toxicidade , Ativadores de Enzimas/síntese química , Humanos , Simulação de Acoplamento Molecular , Sarina/toxicidade
4.
Bioorg Med Chem ; 25(16): 4497-4505, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28684009

RESUMO

A new family of nonquaternary reactivators for nerve agent-inhibited human acetylcholinesterase (hAChE) were designed, synthesized and tested in this paper. It was found that salicylaldoximes were able to quickly cleave the P-S bond of organophosphate and avoid the reinhibition phenomenon in the reactivation process, but they lacked reactivating ability due to poor affinity for AChE. Based on a dual site binding strategy, different peripheral site ligands of AChE were introduced to achieve extra affinity. The in vitro reactivation experiments demonstrated that some of the yielding conjugates exhibited similar or even superior ability to reactivate sarin-, VX- or tabun-inhibited hAChE in comparison with the mono- and bis-pyridinium aldoximes currently used. Moreover, due to greatly improved lipophilicity, these nonquaternary conjugates hold promise for the development of efficient centrally activating reactivators.


Assuntos
Acetilcolinesterase/metabolismo , Reativadores da Colinesterase/farmacologia , Oximas/farmacologia , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Reativadores da Colinesterase/síntese química , Reativadores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Ligantes , Estrutura Molecular , Oximas/síntese química , Oximas/química , Relação Estrutura-Atividade
5.
Bioorg Med Chem Lett ; 24(24): 5743-5748, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25453812

RESUMO

Herein, we described a new class of uncharged non-pyridinium reactivators for nerve agent-inhibited acetylcholinesterase (AChE). Based on a dual site binding strategy, we conjugated the imidazolium aldoxime to different peripheral site ligands (PSLs) of AChE through alkyl chains. Compared with the known quaternary pyridinium reactivators, two of the resulting conjugates (7g and 7h) were highlighted to be the first efficient non-pyridinium oxime conjugates exhibiting similar or superior ability to reactivate sarin-, VX- and tabun-inhibited AChE. Moreover, they were more broad-spectrum reactivators.


Assuntos
Acetilcolinesterase/metabolismo , Substâncias para a Guerra Química/química , Reativadores da Colinesterase/química , Oximas/química , Acetilcolinesterase/química , Sítios de Ligação , Reativadores da Colinesterase/síntese química , Reativadores da Colinesterase/metabolismo , Humanos , Imidazóis/química , Cinética , Ligantes , Simulação de Acoplamento Molecular , Oximas/síntese química , Oximas/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína
6.
ACS Appl Mater Interfaces ; 15(10): 12631-12642, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36867458

RESUMO

It is very important to establish a sustained-release pralidoxime chloride (2-PAM) drug system with brain targeting function for the treatment of neurotoxicant poisoning. Herein, Vitamin B1 (VB1), also known as thiamine, which can specifically bind to the thiamine transporter on the surface of the blood-brain barrier, was incorporated onto the surface of MIL-101-NH2(Fe) nanoparticles with a size of ∼100 nm. Pralidoxime chloride was further loaded within the interior of the above resulted composite by soaking, and a resulting composite drug (denoted as 2-PAM@VB1-MIL-101-NH2(Fe)) with a loading capacity of 14.8% (wt) was obtained. The results showed that the drug release rate of the composite drug was increased in PBS solution with the increase of pH (2-7.4) and a maximum drug release rate of 77.5% at pH 4. Experiments on the treatment of poisoning by gavage with the nerve agent sarin in mice combined with atropine revealed that sustained release of 2-PAM from the composite drug was achieved for more than 72 h. Sustained and stable reactivation of poisoned acetylcholinesterase (AChE) was observed with an enzyme reactivation rate of 42.7% in the ocular blood samples at 72 h. By using both zebrafish brain and mouse brain as models, we found that the composite drug could effectively cross the blood-brain barrier and restore the AChE activity in the brain of poisoned mice. The composite drug is expected to be a stable therapeutic drug with brain targeting and prolonged drug release properties for nerve agent intoxication in the middle and late stages of treatment.


Assuntos
Reativadores da Colinesterase , Agentes Neurotóxicos , Intoxicação , Animais , Camundongos , Acetilcolinesterase/metabolismo , Barreira Hematoencefálica/metabolismo , Inibidores da Colinesterase , Oximas , Peixe-Zebra/metabolismo , Ferro
7.
J Hazard Mater ; 459: 132211, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37572605

RESUMO

Soman, a warfare nerve agent, poses a significant threat by inducing severe brain damage that often results in death. Nonetheless, our understanding of the biological changes underlying persistent neurocognitive dysfunction caused by low dosage of soman remains limited. This study used mice to examine the effects of different doses of soman over time. Phosphoproteomic analysis of the mouse brain is the first time to be used to detect toxic effects of soman at such low or ultra-low doses, which were undetectable based on measuring the activity of acetylcholinesterase at the whole-animal level. We also found that phosphoproteome alterations could accurately track the soman dose, irrespective of the sampling time. Moreover, phosphoproteome revealed a rapid and adaptive cellular response to soman exposure, with the points of departure 8-38 times lower than that of acetylcholinesterase activity. Impaired long-term potentiation was identified in phosphoproteomic studies, which was further validated by targeted quantitative proteomics, immunohistochemistry, and immunofluorescence analyses, with significantly increased levels of phosphorylation of protein phosphatase 1 in the hippocampus following soman exposure. This increase in phosphorylation inhibits long-term potentiation, ultimately leading to long-term memory dysfunction in mice.


Assuntos
Agentes Neurotóxicos , Soman , Camundongos , Animais , Soman/toxicidade , Acetilcolinesterase/metabolismo , Potenciação de Longa Duração , Hipocampo , Inibidores da Colinesterase
8.
Int J Nanomedicine ; 18: 2891-2910, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283712

RESUMO

Introduction: Hepatocellular cancer stem cells (CSCs) play crucial roles in hepatocellular cancer initiation, development, relapse, and metastasis. Therefore, eradication of this cell population is a primary objective in hepatocellular cancer therapy. We prepared a nanodrug delivery system with activated carbon nanoparticles (ACNP) as carriers and metformin (MET) as drug (ACNP-MET), which was able to selectively eliminate hepatocellular CSCs and thereby increase the effects of MET on hepatocellular cancers. Methods: ACNP were prepared by ball milling and deposition in distilled water. Suspension of ACNP and MET was mixed and the best ratio of ACNP and MET was determined based on the isothermal adsorption formula. Hepatocellular CSCs were identified as CD133+ cells and cultured in serum-free medium. We investigated the effects of ACNP-MET on hepatocellular CSCs, including the inhibitory effects, the targeting efficiency, self-renewal capacity, and the sphere-forming capacity of hepatocellular CSCs. Next, we evaluated the therapeutic efficacy of ACNP-MET by using in vivo relapsed tumor models of hepatocellular CSCs. Results: The ACNP have a similar size, a regular spherical shape and a smooth surface. The optimal ratio for adsorption was MET: ACNP=1:4. ACNP-MET could target and inhibit the proliferation of CD133+ population and decrease mammosphere formation and renewal of CD133+ population in vitro and in vivo. Conclusion: These results not only suggest that nanodrug delivery system increased the effects of MET, but also shed light on the mechanisms of the therapeutic effects of MET and ACNP-MET on hepatocellular cancers. ACNP, as a good nano-carrier, could strengthen the effect of MET by carrying drugs to the micro-environment of hepatocellular CSCs.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Metformina , Nanopartículas , Humanos , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Carvão Vegetal , Linhagem Celular Tumoral , Metformina/farmacologia , Células-Tronco Neoplásicas/patologia , Nanopartículas/uso terapêutico , Antígeno AC133/metabolismo , Antígeno AC133/farmacologia , Microambiente Tumoral
9.
RSC Adv ; 12(31): 20251-20258, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35919596

RESUMO

By combining the anionic salt meso-tetra(4-carboxyphenyl)porphyrin (TCPP4-) and the Keggin polyoxometalate cation cluster [Al13O4(OH)24(H2O)12]7+ via a simple ion-exchange method, a hybrid (C48H26N4O8)[Al13O4(OH)24(H2O)12]2(OH)10·18H2O (Al13-TCPP) was prepared and thoroughly characterized as a prototype of polyoxometalate-porphyrin hybrids for the photocatalytic degradation of the mustard gas simulant 2-chloroethyl ethyl sulfide (CEES). The experimental results showed that the catalytic degradation rate of CEES in the presence of Al13-TCPP reached 96.16 and 99.01% in 180 and 90 min in methanol and methanol-water solvent mixture (v/v = 1 : 1), respectively. The reaction followed first-order reaction kinetics, and the half-life and kinetic constant in methanol and solvent mixture were 39.8 min, -0.017 min-1 and 14.7 min, -0.047 min-1. Mechanism analysis indicated that under visible light irradiation in air, CEES was degraded through a combination of oxidation and alcoholysis/hydrolysis in methanol and the methanol-water solvent mixture. The superoxide radical (O2˙-) and singlet molecular oxygen (1O2) generated by Al13-TCPP selectively oxidized CEES into a non-toxic sulfoxide. The singlet oxygen capture experiments showed that Al13-TCPP (Φ = 0.236) had a higher quantum yield of singlet oxygen generation than H4TCPP (Φ = 0.135) under visible light irradiation in air. The material Al13-TCPP has good reusability, and the degradation rate of CEES can still reach 98.37% after being recycled five times.

10.
ACS Omega ; 7(35): 30720-30729, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36092617

RESUMO

A 2-PAM@bio-MOF-1 composite was prepared by cationic exchange of counter N,N-dimethylammonium cations in the pores of the anionic, biocompatible metal-organic framework (bio-MOF-1) with pralidoxime chloride (2-PAM-Cl) by impregnation. In vitro drug release measurements revealed that the release rate of 2-PAM from 2-PAM@bio-MOF-1 in simulated body fluid (SBF) was more than four-fold higher than that in deionized water, indicating that the presence of endogenous cations in SBF triggered the release of 2-PAM through cation exchange. The release of 2-PAM was rapid within the first 10 h but was much slower over the period of 10-50 h. At room temperature, the maximum release rate of 2-PAM was 88.5% (15 mg of 2-PAM@bio-MOF-1 in 1 mL of SBF), indicating that the drug was efficiently released from the composite MOF in SBF. In simulated gastric fluid, 64.3% of 2-PAM was released from bio-MOF-1 into the simulated gastric fluid after 50h. This suggested that 2-PAM@bio-MOF-1 might be effective for enabling the slow release of 2-PAM in the human body. Indeed, the maximum reactivation rate of acetylcholinesterase in sarin-poisoned mice reached 82.5%. In addition, 2-PAM@bio-MOF-1 demonstrated the ability to adsorb and remove sulfur mustard (HD) in solution and from the skin of guinea pigs.

11.
J Obstet Gynaecol Res ; 37(11): 1694-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21651649

RESUMO

Adenoid cystic carcinoma arising from the vulvar sweat glands is a rare malignancy of the female genital tract. We report a case of adenoid cystic carcinoma of sweat glands occurring in the left labia majora of a 52-year-old female patient. The patient underwent radical hemivulvectomy and left inguinal lymph node dissection with negative surgical margins and negative inguinal lymph node metastasis. Then, four episodes of combined chemotherapy without further radiotherapy were given. However, the tumor recurred after 3 months. Currently, the patient has been followed up for 2 years with no distant metastasis. According to our experience, although the tumor has a high tendency of local recurrence after resection, an acceptable survival time of the patient can be achieved with primary surgery.


Assuntos
Carcinoma Adenoide Cístico/patologia , Neoplasias das Glândulas Sudoríparas/patologia , Vulva/patologia , Neoplasias Vulvares/patologia , Carcinoma Adenoide Cístico/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias das Glândulas Sudoríparas/cirurgia , Vulva/cirurgia , Neoplasias Vulvares/cirurgia
12.
J Integr Med ; 19(2): 158-166, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33308987

RESUMO

OBJECTIVE: This study tests whether long-term intake of Allium tuberosum (AT) can alleviate pulmonary inflammation in ovalbumin (OVA)-induced asthmatic mice and evaluates its effect on the intestinal microbiota and innate lymphoid cells (ILCs). METHODS: BALB/c mice were divided into three groups: phosphate buffer saline, OVA and OVA + AT. The asthmatic murine model was established by sensitization and challenge of OVA in the OVA and OVA + AT groups. AT was given to the OVA + AT group by oral gavage from day 0 to day 27. On day 28, mice were sacrificed. Histopathological evaluation of lung tissue was performed using hematoxylin and eosin, and periodic acid-Schiff staining. The levels of IgE in serum, interleukin-5 (IL-5) and IL-13 from bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay. The ILCs from the lung and gut were detected by flow cytometry. 16S ribosomal DNA sequencing was used to analyze the differences in colon microbiota among treatment groups. RESULTS: We found that long-term intake of AT decreased the number of inflammatory cells from BALF, reduced the levels of IL-5 and IL-13 in BALF, and IgE level in serum, and rescued pulmonary histopathology with less mucus secretion in asthmatic mice. 16S ribosomal DNA sequencing results showed that AT strongly affected the colonic bacteria community structure in asthmatic mice, although it had no significant effect on the abundance and diversity of the microbiota. Ruminococcaceae and Desulfovibrionaceae were identified as two biomarkers of the treatment effect of AT. Moreover, AT decreased the numbers of ILCs in both the lung and gut of asthmatic mice. CONCLUSION: The results indicate that AT inhibits pulmonary inflammation, possibly by impeding the activation of ILCs and adjusting the homeostasis of gut microbiota in asthmatic mice.


Assuntos
Cebolinha-Francesa , Microbioma Gastrointestinal , Pneumonia , Animais , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Imunidade Inata , Inflamação/tratamento farmacológico , Pulmão , Linfócitos , Camundongos , Camundongos Endogâmicos BALB C , Pneumonia/tratamento farmacológico
13.
Front Pharmacol ; 12: 713632, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712133

RESUMO

Lung ischemia-reperfusion (IR) injury is induced by pulmonary artery occlusion and reperfusion. Lung IR injury commonly happens after weaning from extracorporeal circulation, lung transplantation, and pulmonary thromboendarterectomy; it is a lethal perioperative complication. A definite therapeutic intervention remains to be determined. It is known that the enzyme activity of angiotensin-converting enzyme 2 (ACE2) is critical in maintaining pulmonary vascular tone and epithelial integrity. In a noxious environment to the lungs, inactivation of ACE2 is mainly due to a disintegrin and metalloprotease 17 (ADAM17) protein-mediated ACE2 shedding. Thus, we assumed that protection of local ACE2 in the lung against ADAM17-mediated shedding would be a therapeutic target for lung IR injury. In this study, we established both in vivo and in vitro models to demonstrate that the damage degree of lung IR injury depends on the loss of ACE2 and ACE2 enzyme dysfunction in lung tissue. Treatment with ACE2 protectant diminazen aceturate (DIZE) maintained higher ACE2 enzyme activity and reduced angiotensin II, angiotensin type 1 receptor, and ADAM17 levels in the lung tissue. Concurrently, DIZE-inhibited oxidative stress and nitrosative stress via p38MAPK and NF-κB pathways consequently reduced release of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1ß. The underlying molecular mechanism of DIZE contributed to its protective effect against lung IR injury and resulted in the improvement of oxygenation index and ameliorating pulmonary pathological damage. We concluded that DIZE protects the lungs from IR injury via inhibition of ADAM17-mediated ACE2 shedding.

14.
J Asthma Allergy ; 13: 509-520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116659

RESUMO

OBJECTIVE: In China, lamb and fish are well-known triggers for an asthma attack. Our investigation aims at assessing whether the long-term intake of lamb meat or Basa fish would aggravate pulmonary inflammation as well as exploring changes in the intestinal microbiota and immune cells in asthmatic mice. MATERIALS AND METHODS: The murine asthmatic model was established by intraperitoneal injection of ovalbumin (OVA) plus aluminum on day 0 and 14 and nebulization of OVA from day 21 to 27. Lamb meat or fish was administered to asthmatic mice by oral gavage from day 0 to 27. RESULTS: Our results showed that long-term consumption of lamb meat or Basa fish in asthmatic mice increased the number of inflammatory cells in bronchoalveolar lavage fluid (BALF), enhanced levels of IL-5, IL-13 in BALF and total IgE in serum, aggravated pulmonary inflammatory cell infiltration and mucus secretion. Long-term oral lamb enhanced the proportion of type 2 innate lymphoid cells (ILC2) from small intestine while it inhibited that of Treg from lung in asthmatic mice. Oral fish showed no remarkable effect on that of ILC2 from lung and small intestine but inhibited that of intestinal Treg in asthmatic mice. What's more, the chao-1 and observed species richness as well as PD whole tree diversity increased in asthmatic mice while these increments were inhibited after lamb treatment. PCA analysis indicated that there were significant differences in the bacterial community composition after lamb or fish treatment in asthmatic mice. Both lamb and fish treatment enhanced the abundance of colonic Alistipes in asthmatic mice. CONCLUSION: Collectively, long-term intake of lamb or fish shapes colonic bacterial communities and aggravates pulmonary inflammation in asthmatic mice, which provides reasonable food guidance for asthmatic patients.

15.
Dalton Trans ; 49(24): 8122-8135, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32495804

RESUMO

ε-[Al13O4(OH)24(H2O)12]7+, which shares similarity with the phosphotriesterase active site ZnII-OH-ZnII, was specially chosen to interact with the cluster α-PMo10V2O405- to form a new three-dimensional intercluster, which crystallized in the monoclinic space group P21/m with Z = 2, for the decontamination of chemical warfare agents. The experimental results showed that 50 mg of the compound decontaminated 96.4% (within 120 min) and 99.5% (within 40 min) of sulfur mustard (HD) (4 µL) and soman (GD) (4 µL), respectively, in ambient conditions. The decontamination processes followed first-order reaction kinetics with a rate constant and half-life of 0.01234 min-1 and 56.15 min for HD and 0.1198 min-1 and 5.78 min for GD, respectively. It was concluded that the α-PMo10V2O405- moiety was responsible for the catalytic oxidation of HD into non-toxic sulfoxide, while the ε-[Al13O4(OH)24(H2O)12]7+ moiety was responsible for the catalytic hydrolysis of HD and GD into nontoxic hydrolysates. Besides, the compound showed notable efficacy for the decontamination of HD on guinea pig skin and of GD on Kunming mouse skin, indicating high potential for use in human skin protection and treatment.

16.
Neuroscience ; 438: 9-24, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32353462

RESUMO

Cyclin-dependent kinase 5 (Cdk5) is a regulator of axon growth and radial neuronal migration in the developing mouse brain, and it plays critical roles in cortical structure formation and brain function. However, the function of Cdk5 in cortico-cortical and cortico-sensorimotor networks in the adult remains largely unknown. In this study, we investigated the function of Cdk5 in the rostral secondary motor cortex (M2) in the male mouse using CRISPR/Cas9 gene editing and somatic brain transgenesis, to produce M2-specific knockdown of Cdk5 in neurons in the male mouse. Mouse deficient in Cdk5 in the M2 exhibited a reduction in both the number of functional synapses and the total basal dendritic length, as well as motor dysfunction. Furthermore, whole-cell patch-clamp recordings in layer V green fluorescent protein (GFP)-tag pyramidal neurons revealed a decrease in the frequency and amplitude of miniature EPSCs and miniature IPSCs, as well as a reduction in the population synaptic responses (fEPSPs) in these mice. Specifically, retrograde labeling showed that Cdk5 knockdown in the M2 caused a reduction in long-range projections to the M2 from the thalamus/prefrontal cortex and claustrum. Collectively, our findings show a new regulatory role of Cdk5 in neural circuit maintenance, and that the changes in neural transmission and circuits in the mice with Cdk5 knockdown in the M2 likely contribute to the motor dysfunction in these animals.


Assuntos
Quinase 5 Dependente de Ciclina , Córtex Motor , Animais , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Masculino , Camundongos , Córtex Motor/metabolismo , Neurônios/metabolismo , Células Piramidais/metabolismo , Transmissão Sináptica
17.
Dalton Trans ; 48(20): 6951-6959, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31041972

RESUMO

Attachment of MOF-5 particles on the surface of carboxymethylated non-woven chitosan cloth (denoted MOF-5@chitosan) was achieved by a layer-by-layer technique in an alternating bath of Zn(OAc)2·2H2O and terephthalic acid solutions. Afterwards, silver nanoparticles were formed/loaded within the resulting MOF-5@chitosan by irradiating at 350 nm wavelength the composite immersed in an aqueous solution of silver nitrate of different concentrations, leading to the formation of ternary composites (denoted Ag@MOF-5@chitosan) which were thoroughly characterized by various techniques. Decontamination of HD over the composites was systematically studied and the results showed that decontamination efficacy increased with the increase of silver amount. The decontamination rate constant and half-life of HD were found to be 0.011 min-1 and 63.0 min over the optimal composite, respectively. Remarkably, attachment of the silver nanoparticles and MOF-5 on the chitosan cloth surface did not interfere with chitosan's original hemostatic capability that was confirmed through the arterial hemostasis of rats. It is expected that the multifunctional composite material can find practical applications in the fields of hemostasis, sterilization and chemical war agent decontamination.

18.
Neural Regen Res ; 14(6): 1029-1036, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30762015

RESUMO

The α5 subunit-containing gamma-amino butyric acid type A receptors (α5 GABAARs) are a distinct subpopulation that are specifically distributed in the mammalian hippocampus and also mediate tonic inhibitory currents in hippocampal neurons. These tonic currents can be enhanced by low-dose isoflurane, which is associated with learning and memory impairment. Inverse agonists of α5 GABAARs, such as L-655,708, are able to reverse the short-term memory deficit caused by low-dose isoflurane in young animals. However, whether these negative allosteric modulators have the same effects on aged rats remains unclear. In the present study, we mainly investigated the effects of L-655,708 on low-dose (1.3%) isoflurane-induced learning and memory impairment in elderly rats. Young (3-month-old) and aged (24-month-old) Wistar rats were randomly assigned to receive L-655,708 0.5 hour before or 23.5 hours after 1.3% isoflurane anesthesia. The Morris Water Maze tests demonstrated that L-655,708 injected before or after anesthesia could reverse the memory deficit in young rats. But in aged rats, application of L-655,708 only before anesthesia showed similar effects. Reverse transcription-polymerase chain reaction showed that low-dose isoflurane decreased the mRNA expression of α5 GABAARs in aging hippocampal neurons but increased that in young animals. These findings indicate that L-655,708 prevented but could not reverse 1.3% isoflurane-induced spatial learning and memory impairment in aged Wistar rats. All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Academy of Military Medical Science of China (approval No. NBCDSER-IACUC-2015128) in December 2015.

19.
J Hazard Mater ; 358: 113-121, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29990797

RESUMO

The Ag NPs@HKUST-1 composites have been successfully prepared with different loading amounts of silver nanoparticles in HKUST-1 featuring a three-dimensional system of channels constructed by benzene-1,3,5-tricarboxylate and dimeric cupric units by a simple one-pot hydrothermal method, and characterized by various microscopy and spectroscopy analysis techniques. The average particle size of Ag NPs increased with the increase of the loading amount of Ag NPs. The experimental results showed that the degradation of sulfur mustard (HD) under ambient conditions followed pseudo-first order reaction kinetics. Additionally, the optimized Ag NPs@HKUST-1 (wherein Ag is l6.67 wt%) exhibited the highest degradation efficacy with an equilibrium rate constant and half-life for HD of 0.0450 min-1 and 15.34 min, respectively. These values were significantly higher than those for pure HKUST-1 with an equilibrium rate constant and half-life for HD of 0.0168 min-1 and 41.29 min, under the same experimental conditions. Gas chromatography-mass spectrometry (GC-MS) analysis on the product of 2-chloroethylethyl sulfide (2-CEES) degraded by Ag NPs@HKUST-1 showed that 2-hydroxyethyl ethyl sulfide (2-HEES) is the sole product, indicating that the remarkable enhancement of the degradation of HD must be due to the Ag NPs, which can promote hydrolysis of the chemical war agent in the composite.

20.
Dalton Trans ; 47(18): 6394-6403, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29687127

RESUMO

Currently extensive effort is compulsively expended to decontaminate efficiently banned chemical war agents. In this work, H5PV2Mo10O40 molecules have been encapsulated in mesoporous MIL-101(Cr), which features two types of mesoporous cages (internal diameters of 29 Å and 34 Å) and microporous windows (diameters of 12 Å and 16 Å), leading to the formation of a new composite H5PV2Mo10O40@MIL-101(Cr) through a simple impregnation method. The composite was characterized thoroughly by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, TG/DTA, and textural analysis thereby confirming the encapsulation of the H5PV2Mo10O40 into MIL-101(Cr). The decontamination efficiency of sulfur mustard (4 µL HD in 40 µL of petroleum ether) by 20 mg of the composite is found to be 97.39% in 120 min under ambient conditions. GC-MS analysis on the decontaminated products using 2-chloroethyl ethyl sulfide (CEES), which has been widely used as a simulant of sulfur mustard, showed that MIL-101(Cr) just decontaminates CEES by adsorption, while CEES can be decontaminated under ambient conditions by a synergetic combination of adsorption of MIL-101(Cr) and subsequent chemical oxidation degradation to nontoxic 2-chloroethyl ethyl sulfoxide (CEESO) due to the presence of highly dispersed H5PV2Mo10O40 within the composites.

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