Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Environ Sci (China) ; 146: 241-250, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38969452

RESUMEN

The dynamics of the composition and antibiotic resistance of the fecal coliform bacteria (FCB) in a typical wastewater treatment plant (WWTP) were investigated concerning the seasonal changes. Results showed that WWTP could remove the FCB concentration by 3∼5 logs within the effluent of 104∼105 CFU/L, but the antibiotic resistant rate of FCB species increased significantly after WWTP. The dominant FCB changed from Escherichia coli in the influent (∼73.0%) to Klebsiella pneumoniae in the effluent (∼53.3%) after WWTP, where the Escherichia coli was removed the most, while Klebsiella pneumoniae was the most persistent. The secondary tank removed the most of FCB (by 3∼4 logs) compared to other processes, but increased all the concerned antibiotic resistant rate. The potential super bugs of FCB community showing resistance to all the target antibiotics were selected in the biological treatment unit of WWTP. The FCB showed the highest multiple antibiotic resistance (92.9%) in total which even increased to 100% in the effluent. Klebsiella has the highest antibiotic resistant rate in FCB, with a multiple antibiotic resistance rate of 98.4%. These indicated that the Klebsiella pneumoniae not just Escherichia coli should be specially emphasized after WWTP concerning the health risk associated with FCB community.


Asunto(s)
Escherichia coli , Heces , Eliminación de Residuos Líquidos , Aguas Residuales , Aguas Residuales/microbiología , Eliminación de Residuos Líquidos/métodos , Heces/microbiología , Escherichia coli/efectos de los fármacos , Antibacterianos/farmacología , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/aislamiento & purificación , Farmacorresistencia Bacteriana , Microbiología del Agua , Klebsiella pneumoniae/efectos de los fármacos
2.
J Neurosci ; 33(45): 17884-96, 2013 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-24198377

RESUMEN

Nav1.8 is a tetrodotoxin-resistant voltage-gated sodium channel selectively expressed in primary sensory neurons. Peripheral inflammation and nerve injury induce Nav1.8 accumulation in peripheral nerves. However, the mechanisms and related significance of channel accumulation in nerves remains unclear. Here we report that KIF5B promotes the forward transport of Nav1.8 to the plasma membrane and axons in dorsal root ganglion (DRG) neurons of the rat. In peripheral inflammation induced through the intraplantar injection of complete Freund's adjuvant, increased KIF5 and Nav1.8 accumulation were observed in the sciatic nerve. The knock-down of KIF5B, a highly expressed member of the KIF5 family in DRGs, reduced the current density of Nav1.8 in both cultured DRG neurons and ND7-23 cells. Overexpression of KIF5B in ND7-23 cells increased the current density and surface expression of Nav1.8, which were abolished through brefeldin A treatment, whereas the increases were lost in KIF5B mutants defective in ATP hydrolysis or cargo binding. Overexpression of KIF5B also decreased the proteasome-associated degradation of Nav1.8. In addition, coimmunoprecipitation experiments showed interactions between the N terminus of Nav1.8 and the 511-620 aa sequence in the stalk domain of KIF5B. Furthermore, KIF5B increased Nav1.8 accumulation, Nav1.8 current, and neuronal excitability detected in the axons of cultured DRG neurons, which were completely abolished by the disruption of interactions between KIF5B and the N terminus of Nav1.8. Therefore, our results reveal that KIF5B is required for the forward transport and axonal function of Nav1.8, suggesting a mechanism for axonal accumulation of Nav1.8 in inflammatory pain.


Asunto(s)
Axones/metabolismo , Ganglios Espinales/metabolismo , Cinesinas/metabolismo , Canal de Sodio Activado por Voltaje NAV1.8/metabolismo , Neuronas/metabolismo , Potenciales de Acción/fisiología , Animales , Membrana Celular/metabolismo , Células Cultivadas , Ganglios Espinales/citología , Inflamación/metabolismo , Cinesinas/genética , Masculino , Canal de Sodio Activado por Voltaje NAV1.8/genética , Neuronas/citología , Transporte de Proteínas/fisiología , Ratas , Ratas Sprague-Dawley
3.
Cell Rep ; 43(8): 114503, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39018245

RESUMEN

Synaptic plasticities, such as long-term potentiation (LTP) and depression (LTD), tune synaptic efficacy and are essential for learning and memory. Current studies of synaptic plasticity in humans are limited by a lack of adequate human models. Here, we modeled the thalamocortical system by fusing human induced pluripotent stem cell-derived thalamic and cortical organoids. Single-nucleus RNA sequencing revealed that >80% of cells in thalamic organoids were glutamatergic neurons. When fused to form thalamocortical assembloids, thalamic and cortical organoids formed reciprocal long-range axonal projections and reciprocal synapses detectable by light and electron microscopy, respectively. Using whole-cell patch-clamp electrophysiology and two-photon imaging, we characterized glutamatergic synaptic transmission. Thalamocortical and corticothalamic synapses displayed short-term plasticity analogous to that in animal models. LTP and LTD were reliably induced at both synapses; however, their mechanisms differed from those previously described in rodents. Thus, thalamocortical assembloids provide a model system for exploring synaptic plasticity in human circuits.


Asunto(s)
Plasticidad Neuronal , Tálamo , Humanos , Tálamo/fisiología , Tálamo/citología , Plasticidad Neuronal/fisiología , Sinapsis/fisiología , Sinapsis/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/citología , Corteza Cerebral/fisiología , Corteza Cerebral/citología , Organoides/metabolismo , Potenciación a Largo Plazo/fisiología , Neuronas/fisiología , Neuronas/metabolismo
4.
bioRxiv ; 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38352415

RESUMEN

Synaptic plasticities, such as long-term potentiation (LTP) and depression (LTD), tune synaptic efficacy and are essential for learning and memory. Current studies of synaptic plasticity in humans are limited by a lack of adequate human models. Here, we modeled the thalamocortical system by fusing human induced pluripotent stem cell-derived thalamic and cortical organoids. Single-nucleus RNA-sequencing revealed that most cells in mature thalamic organoids were glutamatergic neurons. When fused to form thalamocortical assembloids, thalamic and cortical organoids formed reciprocal long-range axonal projections and reciprocal synapses detectable by light and electron microscopy, respectively. Using whole-cell patch-clamp electrophysiology and two-photon imaging, we characterized glutamatergic synaptic transmission. Thalamocortical and corticothalamic synapses displayed short-term plasticity analogous to that in animal models. LTP and LTD were reliably induced at both synapses; however, their mechanisms differed from those previously described in rodents. Thus, thalamocortical assembloids provide a model system for exploring synaptic plasticity in human circuits.

5.
Pharm Res ; 30(1): 269-79, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22975806

RESUMEN

PURPOSE: To make a comparative study on sustained delivery performance of rhIFN with random amorphous and spherical crystal-like ordered self-assemblies. METHODS: The rhIFN self-assemblies were identified in batch crystallization mode. Physico-chemical characteristics were compared, including morphology, XRD, FTIR, CD, biological potency, the dissolution behaviors in vitro and plasma pharmacokinetics in vivo. Moreover, molecular simulation was performed to better understand their binding site and mode. RESULTS: Here, we suggest that random amorphous and spherical ordered self-assemblies allow for long action without new molecular entities generation or carriers employed. By manipulating supersaturation, the ordered aggregates were self-organized at high concentration of Zn(II) (>100 mM) in pH 5.5-6.0, which was the first time that spherical semi-crystals of rhIFN can act as a depot source for the sustained delivery of biologically active proteins. The secondary structure and biological potency of rhIFN were unchanged after aggregation. Compared with that of the native rhIFN, both self-assemblies exhibited slower absorption and extended elimination profiles after s.c. administration, which were characterized as 4.75 ± 0.82 h and 10.58 ± 1.86 h of terminal half-life for random amorphous and spherical ordered self-assemblies, respectively. CONCLUSIONS: The work described here demonstrates the possibility of self-assemblies of biomacromolecules for controllable release application of therapeutic proteins.


Asunto(s)
Antivirales/administración & dosificación , Preparaciones de Acción Retardada/química , Interferones/administración & dosificación , Metales/química , Animales , Antivirales/química , Antivirales/farmacocinética , Antivirales/farmacología , Línea Celular , Humanos , Interferones/química , Interferones/farmacocinética , Interferones/farmacología , Iones/química , Estructura Secundaria de Proteína , Conejos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/farmacología
6.
Yao Xue Xue Bao ; 48(8): 1333-7, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-24187845

RESUMEN

It is a challenging and important project to prolong the in vivo half life of protein and peptide drugs by physicochemical methods without new molecular entities generation. Protein crystallization provides a new strategy for improving the stability and in vivo delivery of these drugs. We show here that recombinant human interferon-alpha (rhIFN) can form spherical crystals. The physical and chemical features of the crystals were characterized, and drug dissolution was determined in vitro. The pharmacokinetics of crystallized interferon after sc injection in rabbit at 1.5 x 10(7) U x kg(-1) was compared to that of soluble form. The crystals were characterized as mono-dispersed spheres, with yield of > 80%, mean diameter size of about 16 microm and crystallinity of 23.2%. The in vitro dissolution behavior of crystallized rhIFN was featured as low initial burst release (21% within the first 2 h) and prolonged cumulative dissolution time up to 72 h without biological potency lost. After sc administration of soluble and crystallized interferon in rabbits, the peak time (T(max)) and half life (t1/2) were prolonged from (1.80 +/- 0.45) h and (1.35 +/- 0.35) h to (13.20 +/- 2.68) h and (10.68 +/- 1.97) h, respectively. The corresponding peak concentration decreased from (1 411.10 +/- 575.28) U x mL(-1) to (721.37 +/- 206.55) U x mL(-1). PK/PD analysis indicated that (96.87 +/- 20.30) % of relative bioavailability was obtained. The research results of this work will provide important academic value and application prospect for improving clinical therapeutic effect and development of biomacromolecules delivery system for protein and peptide drugs.


Asunto(s)
Antivirales/administración & dosificación , Sistemas de Liberación de Medicamentos , Interferón-alfa/administración & dosificación , Animales , Antivirales/química , Antivirales/farmacocinética , Disponibilidad Biológica , Cristalización , Preparaciones de Acción Retardada , Semivida , Humanos , Inyecciones Subcutáneas , Interferón-alfa/química , Interferón-alfa/farmacocinética , Masculino , Conejos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética , Solubilidad , Propiedades de Superficie
7.
Transl Oncol ; 35: 101717, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37320872

RESUMEN

Cancer-associated fibroblasts (CAFs) consist of heterogeneous cellular populations that contribute critical roles in head and neck squamous cell carcinoma (HNSCC). A series of computer-aided analyses were performed to determine various aspects of CAFs in HNSCC, including their cellular heterogeneity, prognostic value, relationship with immune suppression and immunotherapeutic response, intercellular communication, and metabolic activity. The prognostic significance of CKS2+ CAFs was verified using immunohistochemistry. Our findings revealed that fibroblasts group demonstrated prognostic significance, with the CKS2+ subset of inflammatory CAFs (iCAFs) exhibiting a significant correlation with unfavorable prognosis and being localized in close proximity to cancer cells. Patients with a high infiltration of CKS2+ CAFs had a poor overall survival rate. There is a negative correlation between CKS2+ iCAFs and cytotoxic CD8+ T cells and natural killer (NK) cells, while a positive correlation was found with exhausted CD8+ T cells. Additionally, patients in Cluster 3, characterized by a high proportion of CKS2+ iCAFs, and patients in Cluster 2, characterized by a high proportion of CKS2- iCAFs and CENPF-/MYLPF- myofibroblastic CAFs (myCAFs), did not exhibit significant immunotherapeutic responses. Moreover, close interactions was confirmed to exist between cancer cells and CKS2+ iCAFs/ CENPF+ myCAFs. Furthermore, CKS2+ iCAFs demonstrated the highest level of metabolic activity. In summary, our study enhances the understanding of the heterogeneity of CAFs and provided insights into improving the efficacy of immunotherapies and prognostic accuracy for HNSCC patients.

8.
Pharm Res ; 29(1): 158-69, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21748536

RESUMEN

PURPOSE: To investigate anti-solvent crystallization and growth mechanism of nitrendipine spherical crystals in an aqueous solution containing polymeric additives. METHODS: Size and shape of crystals were investigated using laser diffractometry, optical microscopy and scanning electron microscopy (SEM). Crystalline form was determined by X-ray powder diffractometer (XRPD). During crystal growth, morphological changes at different time points were observed using SEM. RESULTS: Morphology of nitrendipine crystals was affected by polymers and temperature. Monodispersed micro-spherical crystals were obtained when polyvinyl alcohol (PVA) and PEG 200 were present in crystallization medium at 2°C. During crystallization, large number of amorphous nanoparticles was first observed, followed by aggregation into a core for spherical crystals. Once crystalline state was achieved, rapid growth on core surface was observed with amorphous particles acting as a reservoir allowing formation of star-like particles with needle-like subunits. Spherical crystals were formed by filling the gap between needle-like distinct crystalline units of star-like templates with molecules from dissolved amorphous particles. CONCLUSIONS: Monodispersed nitrendipine spherical crystals were obtained using carefully controlled conditions. A mechanism for the nitrendipine spherical crystal growth is suggested. These findings provide a new insight into spherulitic crystallization of active pharmaceutical ingredients.


Asunto(s)
Bloqueadores de los Canales de Calcio/química , Composición de Medicamentos/métodos , Nitrendipino/química , Polímeros/química , Rastreo Diferencial de Calorimetría , Cristalización , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Polietilenglicoles/química , Alcohol Polivinílico/química , Soluciones/química , Solventes , Temperatura , Agua/química , Difracción de Rayos X
9.
Bioresour Technol ; 344(Pt A): 126179, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34695583

RESUMEN

Cassava alcohol wastewater (CAW) was utilized as a mixed feedstock to explore whether the addition of CAW could improve the anaerobic digestion of Molasses alcohol wastewater (MAW). The result showed that the rate of removal of the soluble chemical oxygen demand in the M treatment mixed with CAW was 70.13 ± 0.16%, which was significantly higher than that of the C treatment (only MAW), which was 61.23 ± 0.36%. Co-digestion in the M treatment resulted in higher methane production, achieving 23.89% increase in methane yield compared to C treatment. The addition of CAW helps to alleviate the accumulation of volatile fatty acids (397.06 ± 141.82 mg·L-1), enhance the stability of system and promote the establishment of stable and active microbial communities. Microbial community structure analysis indicated that hydrolytic bacteria such as Bacteroidetes, Firmicutes, and Proteobacteria, and acetoclastic methanogens, including Methanosaeta and Methanosarcina were more abundant in the co-digests.


Asunto(s)
Manihot , Aguas Residuales , Anaerobiosis , Reactores Biológicos , Metano , Methanosarcina , Melaza/análisis , Aguas del Alcantarillado
10.
Front Neural Circuits ; 15: 769969, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34955759

RESUMEN

Schizophrenia is a severe, chronic psychiatric disorder that devastates the lives of millions of people worldwide. The disease is characterized by a constellation of symptoms, ranging from cognitive deficits, to social withdrawal, to hallucinations. Despite decades of research, our understanding of the neurobiology of the disease, specifically the neural circuits underlying schizophrenia symptoms, is still in the early stages. Consequently, the development of therapies continues to be stagnant, and overall prognosis is poor. The main obstacle to improving the treatment of schizophrenia is its multicausal, polygenic etiology, which is difficult to model. Clinical observations and the emergence of preclinical models of rare but well-defined genomic lesions that confer substantial risk of schizophrenia (e.g., 22q11.2 microdeletion) have highlighted the role of the thalamus in the disease. Here we review the literature on the molecular, cellular, and circuitry findings in schizophrenia and discuss the leading theories in the field, which point to abnormalities within the thalamus as potential pathogenic mechanisms of schizophrenia. We posit that synaptic dysfunction and oscillatory abnormalities in neural circuits involving projections from and within the thalamus, with a focus on the thalamocortical circuits, may underlie the psychotic (and possibly other) symptoms of schizophrenia.


Asunto(s)
Síndrome de DiGeorge , Esquizofrenia , Síndrome de DiGeorge/genética , Humanos , Esquizofrenia/genética , Tálamo
11.
Nanomaterials (Basel) ; 11(8)2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-34443953

RESUMEN

The rational design of direct Z-scheme heterostructural photocatalysts using solar energy is promising for energy conversion and environmental remediation, which depends on the precise regulation of redox active sites, rapid spatial separation and transport of photoexcited charge and a broad visible light response. The Bi2WO6 materials have been paid more and more attention because of their unique photochemical properties. In this study, S2- doped Bi2WO6-x coupled with twin crystal ZnIn2S4 nanosheets (Sov-BWO/T-ZIS) were prepared as an efficient photocatalyst by a simple hydrothermal method for the removal of tetracycline hydrochloride (TCH). Multiple methods (XRD, TEM, XPS, EPR, UV vis DRS, PL etc.) were employed to systematically investigate the morphology, structure, composition and photochemical properties of the as-prepared samples. The XRD spectrum indicated that the S2- ions were successfully doped into the Sov-BWO component. XPS spectra and photoelectrochemical analysis proved that S2- served as electronic bridge and promoted captured electrons of surface oxygen vacancies transfer to the valence band of T-ZIS. Through both experimental and in situ electron paramagnetic resonance (in situ EPR) characterizations, a defined direct Z-scheme heterojunction in S-BWO/T-ZIS was confirmed. The improved photocatalytic capability of S-BWO/T-ZIS results ascribed that broadened wavelength range of light absorption, rapid separation and interfacial transport of photoexcited charge, precisely regulated redox centers by optimizing the interfacial transport mode. Particularly, the Sov-50BWO/T-ZIS Z-scheme heterojunction exhibited the highest photodegradation rate was 95% under visible light irradiation. Moreover, this heterojunction exhibited a robust adsorption and degradation capacity, providing a promising photocatalyst for an organic pollutant synergistic removal strategy.

12.
Pharm Res ; 27(9): 1965-76, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20585842

RESUMEN

PURPOSE: To investigate the effect of crystal size on the dissolution and oral absorption of nitrendipine, a poorly soluble drug, in rats. METHODS: Five types of nitrendipine crystal suspensions with different particle sizes (200 nm, 620 nm, 2.7 microm, 4.1 microm, 20.2 microm) were prepared either by the precipitation-ultrasonication or the anti-solvent precipitation method. The simulated intestinal fluid in the fasted state (FaSSIF) was selected as the dissolution medium, and the dissolution behaviors of different nitrendipine crystals were simulated based on a Noyes-Whitney type equation. The in vivo absorption and the absolute bioavailability of the different nitrendipine crystals were evaluated in Wistar rats. RESULTS: The dissolution rate of nitrendipine was significantly increased by a reduction in particle size. The dissolution test in FaSSIF could discriminate between the differences in the dissolution rates of the different particle sizes, and the simulated results were in agreement with the observed dissolution curves. From the simulated T(50%) values (50% dissolution time), the dissolution rates of crystals with particle sizes of 200 nm, 620 nm, 2.7 microm, 4.1 microm and 20.2 microm were calculated to be 5.1 x 10(4), 1.0 x 10(4), 237, 64 and 11-fold greater than that of the raw crystals and resulted in absolute bioavailability of 61.4% 51.5%, 29.4%, 26.7%, 24.7%, respectively. The reduction in the drug particle size correlated well with incremental improvements in oral absorption. A good linear relationship was observed between the Log (T(50%)) and the absolute bioavailability of nitrendipine. CONCLUSIONS: The dissolution rate and the oral bioavailability of nitrendipine were significantly affected by the crystal size, and the oral bioavailability could be improved significantly by preparing it as nanocrystals. FaSSIF can be used to predict differences in oral absorption of crystals with different particle sizes.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacocinética , Mucosa Bucal/metabolismo , Nitrendipino/farmacocinética , Absorción , Administración Oral , Animales , Disponibilidad Biológica , Bloqueadores de los Canales de Calcio/administración & dosificación , Bloqueadores de los Canales de Calcio/sangre , Bloqueadores de los Canales de Calcio/química , Rastreo Diferencial de Calorimetría , Cromatografía Líquida de Alta Presión , Simulación por Computador , Cristalización , Relación Dosis-Respuesta a Droga , Masculino , Microscopía Electrónica de Rastreo , Nanopartículas/química , Nitrendipino/administración & dosificación , Nitrendipino/sangre , Nitrendipino/química , Tamaño de la Partícula , Difracción de Polvo , Ratas , Ratas Wistar , Solubilidad , Propiedades de Superficie , Difracción de Rayos X
13.
Drug Dev Ind Pharm ; 36(12): 1389-97, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21050135

RESUMEN

OBJECTIVE: This study presents a preliminary exploration on extending the half-life of therapeutic proteins by crystallization strategy without new molecular entities generation. METHODS: Recombinant human interferon (rhIFN) α-2b, a model protein drug in this case, was crystallized using a hanging-drop vapor diffusion method. A novel chelating technique with metal ions was employed to promote crystals formation. RESULTS: The effects of key factors such as seeding protein concentration, pH of the hanging drop, ionic strength of the equilibration solution, and precipitants were investigated. Size-exclusion liquid chromatography, antiviral activity determination, and enzyme-linked immunosorbent assay indicated that both the molecular integrity and biological potency of rhIFN were not significantly affected by crystallization process. In addition, the in vitro release behavior of rhIFN from crystal lattice was characterized by an initial fast release, followed by a sustained release up to 48 hour. CONCLUSION: The work described here suggested an exciting possibility of therapeutic protein crystals as a long-acting formulation.


Asunto(s)
Antivirales/química , Quelantes/química , Interferón-alfa/química , Zinc/química , Antivirales/farmacología , Cationes Bivalentes , Células Cultivadas , Química Farmacéutica , Cromatografía en Gel , Cristalización , Preparaciones de Acción Retardada , Difusión , Ensayo de Inmunoadsorción Enzimática , Semivida , Humanos , Concentración de Iones de Hidrógeno , Interferón alfa-2 , Interferón-alfa/farmacología , Proteínas Recombinantes , Vesiculovirus/efectos de los fármacos
14.
Pharm Dev Technol ; 15(6): 644-52, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19943738

RESUMEN

The key structural requirement for the antitumor activity of 10-hydroxycamptothecin (HCPT) is the intact lactone moiety which is always instability and suffered from pH-dependent hydrolysis. The aim of this study was to evaluate the protection effects of liposomal encapsulation on the labile lactone ring. Mono-modal dispersed quasi-spherical liposomes with mean diameter of 145 nm and high drug entrapment efficiency of 90% were obtained under optimal conditions. The in vitro hydrolysis kinetics behaviors of lactone were studied in varied pH buffers. Compared to that of free HCPT in solution formulation, both the hydrolysis half-life and observed equilibrium constant of liposomal HCPT were increased significantly along with the decreased apparent hydrolysis rate constant. The plasma pharmacokinetics was studied by assessing the lactone stability versus time profiles in vivo following intravenous administration of free and liposomal HCPT. The liposomal encapsulation led to a twofold increase in the AUC values and significant decrease in the plasma clearance of lactone (P < 0.05). There was a good correlation between in vitro and in vivo stability of HCPT-lactone. These results suggested a potential application of the novel liposome formulation for the stable delivery system of HCPT.


Asunto(s)
Antineoplásicos Fitogénicos/farmacocinética , Camptotecina/análogos & derivados , Animales , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/química , Área Bajo la Curva , Camptotecina/administración & dosificación , Camptotecina/química , Camptotecina/farmacocinética , Estabilidad de Medicamentos , Semivida , Concentración de Iones de Hidrógeno , Hidrólisis , Liposomas , Conejos , Factores de Tiempo
15.
Int J Hypertens ; 2020: 3284769, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32099671

RESUMEN

Up to date, human urotensin II (UII) is the most potent vasoconstrictor in mammalian animals. To explore whether UII played an important role in the development of hypertension, we conducted a prospective study in Changshu city, China. The baseline investigation was carried out in 2007, and the first follow-up investigation was conducted in 2013. From the participants, we randomly obtained 2000 normotensive subjects aged 40 years and older without any severe disease at baseline and examined plasma UII and endothelin-1 (ET-1) with their blood samples at baseline. Logistic models were used to analyze the association between baseline UII, baseline ET-1, and newly occurring hypertension. In 1,819 subjects with complete data, 723 subjects developed into hypertensive in about five years. After adjusting some potential confounders, the odds ratio (95% confidence interval) for risk of hypertension comparing the highest with the lowest quartile of baseline UII was 0.888 (0.689-1.144). The role of UII in the development of hypertension was not found in the current study; therefore, further research studies should be conducted to explore the relationship between UII and hypertension.

16.
J Hypertens ; 38(4): 625-632, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31834126

RESUMEN

OBJECTIVES: Although hyperuricemia, microalbuminuria, and hypertension are highly correlated, their temporal relationship is largely unknown. We aimed to examine whether microalbuminuria mediated the association between hyperuricemia and hypertension. METHODS: Leveraging a longitudinal cohort including 1981 Chinese adults who had blood pressures, urinary albumin to creatinine ratio (UACR), and uric acid measured twice 4 years apart, we examined the temporal relationships among hyperuricemia, microalbuminuria, and hypertension by cross-lagged panel analysis followed by a causal mediation analysis to confirm the temporal consequence. Age, sex, education level, cigarette smoking, alcohol consumption, obesity, blood glucose, and lipids were adjusted. RESULTS: The cross-lagged panel analysis demonstrated that the relationship from baseline UACR to follow-up uric acid was significantly smaller than that from baseline uric acid to follow-up UACR (ß: 0.010 vs. 0.054, P < 0.001). The relationships from baseline blood pressures to follow-up UACR were also significantly smaller than that from baseline UACR to follow-up blood pressures (ß: 0.031 vs. 0.092, P < 0.001 for systolic and ß: 0.015 vs. 0.096, P < 0.001 for diastolic). The causal mediation analysis found that UACR partially mediated the association of baseline uric acid with follow-up SBP (mediate proportion: 9.14%, 95% CI: 1.58-23.00%) and DBP (mediate proportion: 7.38%, 95% CI: 1.05-19.00%). CONCLUSION: Microalbuminuria may follow elevated uric acid and partially mediate its effect on future risk of hypertension in Chinese adults.


Asunto(s)
Albuminuria/complicaciones , Presión Sanguínea/fisiología , Hipertensión/complicaciones , Hiperuricemia/complicaciones , Ácido Úrico/sangre , Adulto , Albuminuria/sangre , Albuminuria/fisiopatología , Pueblo Asiatico , Glucemia , Estudios de Cohortes , Femenino , Humanos , Hipertensión/sangre , Hipertensión/fisiopatología , Hiperuricemia/sangre , Hiperuricemia/fisiopatología , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Factores de Riesgo
17.
Yao Xue Xue Bao ; 44(8): 845-51, 2009 Aug.
Artículo en Zh | MEDLINE | ID: mdl-20055150

RESUMEN

Crystallization has been widely applied in pharmaceutical formulations as an effective approach to improve the stability and efficacy of small agents. However protein crystals are suffered from limitation in the drug delivery system due to their complex crystallization behaviors. With development of crystallization technologies and their industrial application, protein crystals are receiving more and more attentions as a novel delivery system for biomacromolecules. Crystals with thermodynamic stable structure can improve the physical and chemical stability of protein drugs and present a sustained release behavior. On the basis of pertinent literatures, this review introduces the recent research situation and development process of protein crystals as drug delivery system. Moreover, the crystallization process of proteins, as well as the preparation and potential application are discussed systematically.


Asunto(s)
Sistemas de Liberación de Medicamentos , Preparaciones Farmacéuticas/administración & dosificación , Proteínas/química , Cristalización
18.
Neuropharmacology ; 138: 97-105, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29883765

RESUMEN

Ionotropic GABAA receptors expressing at the axon initial segment (AIS) of glutamatergic pyramidal cell (PC) in the cortex plays critical roles in regulating action potential generation. However, it remains unclear whether these receptors also express at the AIS of cortical GABAergic interneurons. In mouse prefrontal cortical slices, we performed experiments at the soma and AIS of the two most abundant GABAergic interneurons: parvalbumin (PV) and somatostatin (SST) positive neurons. Local application of GABA at the perisomatic axonal regions could evoke picrotoxin-sensitive currents with a reversal potential near the Cl- equilibrium potential. Puffing agonists to outside-out patches excised from AIS confirmed the expression of GABAA receptors. Further pharmacological experiments revealed that GABAA receptors in AIS of PV neurons contain α1 subunits, different from those containing α2/3 in AIS and α4 in axon trunk of layer-5 PCs. Cell-attached recording at the soma of PV and SST neurons revealed that the activation of AIS GABAA receptors inhibits the action potential generation induced by synaptic stimulation. Together, our results demonstrate that the AIS of PV and SST neurons express GABAA receptors with distinct subunit composition, which exert an inhibitory effect on neuronal excitability in these inhibitory interneurons.


Asunto(s)
Potenciales de Acción/fisiología , Segmento Inicial del Axón/metabolismo , Neuronas GABAérgicas/metabolismo , Interneuronas/metabolismo , Corteza Prefrontal/metabolismo , Receptores de GABA-A/metabolismo , Potenciales de Acción/efectos de los fármacos , Animales , Segmento Inicial del Axón/efectos de los fármacos , Cloruros/metabolismo , Neuronas GABAérgicas/efectos de los fármacos , Interneuronas/efectos de los fármacos , Ratones Transgénicos , Inhibición Neural/efectos de los fármacos , Inhibición Neural/fisiología , Parvalbúminas/metabolismo , Corteza Prefrontal/efectos de los fármacos , Células Piramidales/efectos de los fármacos , Células Piramidales/metabolismo , Somatostatina/metabolismo , Técnicas de Cultivo de Tejidos
19.
J Am Heart Assoc ; 7(22): e010723, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30571489

RESUMEN

Background Although hypertension and microalbuminuria are closely interrelated, the magnitude and temporal sequence of the bidirectional association between hypertension and microalbuminuria are largely unknown. We aimed to delineate the bidirectional and temporal relationship between hypertension and microalbuminuria. Methods and Results Leveraging a longitudinal cohort of Chinese adults who had blood pressure and urinary albumin measured twice 4 years apart, we examined the temporal association between hypertension and microalbuminuria by bidirectional and cross-lagged panel analysis. All participants were free of cardiovascular disease and chronic kidney disease at baseline. Bidirectional association analysis found that baseline microalbuminuria predicted the risk of incident hypertension (odds ratio=1.75, P=0.028), and baseline blood pressure also significantly predicted the risk of microalbuminuria (odds ratios=1.27 and 1.21 for a per-SD increase in systolic and diastolic blood pressure, respectively; all P<0.05). Cross-lagged panel analysis demonstrated a bottom-line significant relationship of baseline systolic blood pressure to follow-up urinary albumin ( P=0.079), which is significantly weaker than the other direction of the relationship of baseline urinary albumin to follow-up blood pressures (all P<0.001). Conclusions These findings indicate a significant bidirectional association between microalbuminuria and hypertension in Chinese adults. Elevated urinary albumin excretion is more likely to precede hypertension. The causality between microalbuminuria and hypertension needs further investigation.


Asunto(s)
Albuminuria/complicaciones , Hipertensión/complicaciones , Albuminuria/epidemiología , Presión Sanguínea , China/epidemiología , Femenino , Humanos , Hipertensión/epidemiología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores de Riesgo
20.
Front Cell Neurosci ; 10: 239, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27803650

RESUMEN

Cortical fast-spiking (FS) neurons generate high-frequency action potentials (APs) without apparent frequency accommodation, thus providing fast and precise inhibition. However, the maximal firing frequency that they can reach, particularly in primate neocortex, remains unclear. Here, by recording in human, monkey, and mouse neocortical slices, we revealed that FS neurons in human association cortices (mostly temporal) could generate APs at a maximal mean frequency (Fmean) of 338 Hz and a maximal instantaneous frequency (Finst) of 453 Hz, and they increase with age. The maximal firing frequency of FS neurons in the association cortices (frontal and temporal) of monkey was even higher (Fmean 450 Hz, Finst 611 Hz), whereas in the association cortex (entorhinal) of mouse it was much lower (Fmean 215 Hz, Finst 342 Hz). Moreover, FS neurons in mouse primary visual cortex (V1) could fire at higher frequencies (Fmean 415 Hz, Finst 582 Hz) than those in association cortex. We further validated our in vitro data by examining spikes of putative FS neurons in behaving monkey and mouse. Together, our results demonstrate that the maximal firing frequency of FS neurons varies between species and cortical areas.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA